Heat Injury and Illness Prevention in Outdoor and Indoor Work Settings, 70698-71073 [2024-14824]

Agencies

• DEPARTMENT OF LABOR
• Occupational Safety and Health Administration

[Federal Register Volume 89, Number 169 (Friday, August 30, 2024)]
[Proposed Rules]
[Pages 70698-71073]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2024-14824]



[[Page 70697]]

Vol. 89

Friday,

No. 169

August 30, 2024

Part II





Department of Labor





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Occupational Safety and Health Administration





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29 CFR Part 1910, 1915, 1917, et al.





Heat Injury and Illness Prevention in Outdoor and Indoor Work Settings; 
Proposed Rule

Federal Register / Vol. 89, No. 169 / Friday, August 30, 2024 / 
Proposed Rules

[[Page 70698]]


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DEPARTMENT OF LABOR

Occupational Safety and Health Administration

29 CFR Part 1910, 1915, 1917, 1918, 1926, and 1928

[Docket No. OSHA-2021-0009]
RIN 1218-AD39


Heat Injury and Illness Prevention in Outdoor and Indoor Work 
Settings

AGENCY: Occupational Safety and Health Administration (OSHA), Labor.

ACTION: Notice of proposed rulemaking (NPRM); request for comments.

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SUMMARY: OSHA is proposing to issue a new standard, titled Heat Injury 
and Illness Prevention in Outdoor and Indoor Work Settings. The 
standard would apply to all employers conducting outdoor and indoor 
work in all general industry, construction, maritime, and agriculture 
sectors where OSHA has jurisdiction, with some exceptions. It would be 
a programmatic standard that would require employers to create a plan 
to evaluate and control heat hazards in their workplace. It would more 
clearly set forth employer obligations and the measures necessary to 
effectively protect employees from hazardous heat. OSHA requests 
comments on all aspects of the proposed rule.

DATES: Comments to this NPRM (including requests for a hearing) and 
other information must be submitted by December 30, 2024.
    Informal public hearing: OSHA will schedule an informal public 
hearing on the proposed rule if requested during the comment period. If 
a hearing is requested, the location and date of the hearing, 
procedures for interested parties to notify the agency of their 
intention to participate, and procedures for participants to submit 
their testimony and documentary evidence will be announced in the 
Federal Register.

ADDRESSES: 
    Written comments: You may submit comments and attachments, 
identified by Docket No. OSHA-2021-0009, electronically at https://www.regulations.gov, which is the Federal e-Rulemaking Portal. Follow 
the instructions online for making electronic submissions. After 
accessing ``all documents and comments'' in the docket (Docket No. 
OSHA-2021-0009), check the ``proposed rule'' box in the column headed 
``Document Type,'' find the document posted on the date of publication 
of this document, and click the ``Comment Now'' link. When uploading 
multiple attachments to regulations.gov, please number all of your 
attachments because regulations.gov will not automatically number the 
attachments. This will be very useful in identifying all attachments. 
For example, Attachment 1--title of your document, Attachment 2--title 
of your document, Attachment 3--title of your document. For assistance 
with commenting and uploading documents, please see the Frequently 
Asked Questions on regulations.gov.
    Instructions: All submissions must include the agency's name and 
the docket number for this rulemaking (Docket No. OSHA-2021-0009). All 
comments, including any personal information you provide, are placed in 
the public docket without change and may be made available online at 
https://www.regulations.gov. Therefore, OSHA cautions commenters about 
submitting information they do not want made available to the public, 
or submitting materials that contain personal information (either about 
themselves or others), such as Social Security Numbers and birthdates.
    Docket citations: This Federal Register document references 
material in Docket No. OSHA-2021-0009, which is the docket for this 
rulemaking.
    Citations to documents: The docket referenced most frequently in 
this document is the docket for this rulemaking, docket number OSHA-
2021-0009, cited as Document ID OSHA-2021-0009. Documents in the docket 
get an individual document identification number, for example ``OSHA-
2021-0009-0047.'' Because this is the most frequently cited docket, the 
citation is shortened to indicate only the document number. The example 
is cited in the NPRM as ``Document ID 0047.''
    Documents cited in this NPRM are available in the rulemaking docket 
(Docket ID OSHA-2021-0009). They are available to read and download by 
searching the docket number or document ID number at https://www.regulations.gov. Each docket index lists all documents in that 
docket, including public comments, supporting materials, meeting 
transcripts, and other documents. However, some documents (e.g., 
copyrighted material) in the dockets are not available to read or 
download from that website. All documents in the dockets are available 
for inspection at the OSHA Docket Office. This information can be used 
to search for a supporting document in the docket at 
www.regulations.gov. Contact the OSHA Docket Office at (202) 693-2350 
(TTY number: 877-889-5627) for assistance in locating docket 
submissions.

FOR FURTHER INFORMATION CONTACT: 
    For press inquiries: Contact Frank Meilinger, Director, OSHA Office 
of Communications, Occupational Safety and Health Administration; 
telephone: (202) 693-1999; email: [email protected].
    General information and technical inquiries: Contact Stephen 
Schayer, Director, Office of Physical Hazards and Others, OSHA 
Directorate of Standards and Guidance; telephone: (202) 693-1950; 
email: [email protected].
    Copies of this Federal Register notice: Electronic copies are 
available at https://www.regulations.gov. This Federal Register notice, 
as well as news releases and other relevant information, also are 
available at OSHA's web page at https://www.osha.gov.
    The docket is available at https://www.regulations.gov, the Federal 
eRulemaking Portal. A ``100-word summary'' is also available on https://www.regulations.gov. For additional information on submitting items 
to, or accessing items in, the docket, please refer to the ADDRESSES 
section of this NPRM. Most exhibits are available at https://www.regulations.gov; some exhibits (e.g., copyrighted material) are not 
available to download from that web page. However, all materials in the 
dockets are available for inspection and copying at the OSHA Docket 
Office.

SUPPLEMENTARY INFORMATION: 

Table of Contents

I. Executive Summary
II. Pertinent Legal Authority
    A. Introduction
    B. Significant Risk
    C. Feasibility
    D. High Degree of Employee Protection
III. Background
    A. Introduction
    B. Need for Proposal
    C. Events Leading to Proposal
    D. Other Standards
IV. Health Effects
    A. Introduction
    B. General Mechanisms of Heat-Related Health Effects
    C. Identifying Cases of Heat-Related Health Effects
    D. Heat-Related Deaths
    E. Heat Stroke
    F. Heat Exhaustion
    G. Heat Syncope
    H. Rhabdomyolysis
    I. Hyponatremia
    J. Heat Cramps
    K. Heat Rash
    L. Heat Edema
    M. Kidney Health Effects
    N. Other Health Effects
    O. Factors That Affect Risk for Heat-Related Health Effects
    P. Heat-Related Injuries

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V. Risk Assessment
    A. Risk Assessment
    B. Basis for Initial and High Heat Triggers
    C. Risk Reduction
VI. Significance of Risk
    A. Material Harm
    B. Significant Risk
    C. Preliminary Conclusions
VII. Explanation of Proposed Requirements
    A. Paragraph (a) Scope and Application
    B. Paragraph (b) Definitions
    C. Paragraph (c) Heat Injury and Illness Prevention Plan
    D. Paragraph (d) Identifying Heat Hazards
    E. Paragraph (e) Requirements at or Above the Initial Heat 
Trigger
    F. Paragraph (f) Requirements at or Above the High Heat Trigger
    G. Paragraph (g) Heat Illness and Emergency Response and 
Planning
    H. Paragraph (h) Training
    I. Paragraph (i) Recordkeeping
    J. Paragraph (j) Requirements Implemented at no Cost to 
Employees
    K. Paragraph (k) Dates
    L. Paragraph (l) Severability
VIII. Preliminary Economic Analysis and Initial Regulatory 
Flexibility Analysis
    A. Market Failure and Need for Regulation
    B. Profile of Affected Industries
    C. Costs of Compliance
    D. Economic Feasibility
    E. Benefits
    F. Initial Regulatory Flexibility Analysis
    G. Distributional Analysis
    H. Appendix A. Description of the Cost Savings Approach
    I. Appendix B. Review of Literature on Effects of Heat Exposure 
on Non-Health Outcomes
    J. Appendix C. Heat Exposure Methodology Used in Distributional 
Analysis
    K. Appendix D. Definitions of Core Industry Categories Used in 
Cost Analysis
IX. Technological Feasibility
X. Additional Requirements
    A. Unfunded Mandates Reform Act, 2 U.S.C. 1501 et seq.
    B. Consultation and Coordination With Indian Tribal Governments/
Executive Order 13175
    C. Consultation With the Advisory Committee on Construction 
Safety and Health
    D. Environmental Impacts
    E. Consensus Standards
    F. Incorporation by Reference
    G. Protection of Children From Environmental Health Risks and 
Safety Risks
    H. Federalism
    I. Requirements for States With OSHA-Approved State Plans
    J. OMB Review Under the Paperwork Reduction Act of 1995
XI. Authority and Signature

I. Executive Summary

    Heat is the leading cause of death among all weather-related 
phenomena in the United States. Excessive heat in the workplace can 
cause a number of adverse health effects, including heat stroke and 
even death, if not treated properly. Yet, there is currently no Federal 
OSHA standard that regulates heat stress hazards in the workplace. 
Although several governmental and non-governmental organizations have 
published regulations and guidance to help protect workers from heat 
hazards, OSHA believes that a mandatory Federal standard specific to 
heat-related injury and illness prevention is necessary to address the 
hazards posed by occupational heat exposure. OSHA has preliminarily 
determined that this proposed rule would substantially reduce the risk 
posed by occupational exposure to hazardous heat by clearly setting 
forth employer obligations and the measures necessary to effectively 
protect exposed workers.
    OSHA is proposing this standard pursuant to the Occupational Safety 
and Health Act of 1970, 29 U.S.C. 651 et seq. (OSH Act or Act). The Act 
authorizes the agency to issue safety or health standards that are 
``reasonably necessary or appropriate'' to provide safe or healthful 
employment and places of employment (29 U.S.C. 652(8)). A standard is 
reasonably necessary or appropriate when a significant risk of material 
harm exists in the workplace and the standard would substantially 
reduce or eliminate that workplace risk. Applicable legal requirements 
are more fully discussed in Section II., Pertinent Legal Authority.
    Workers in both outdoor and indoor work settings without adequate 
climate controls are at risk of hazardous heat exposure. Certain heat-
generating processes, machinery, and equipment (e.g., hot tar ovens, 
furnaces) can also cause heat hazards when cooling measures are not in 
place. Based on the best available evidence, as discussed in this 
preamble, OSHA has preliminarily determined that exposure to hazardous 
heat in the workplace poses a significant risk of serious injury and 
illness. This finding of a significant risk of material harm is based 
on the health consequences associated with exposure to heat (see 
Section IV., Health Effects) as well as the risk assessment (see 
Section V., Risk Assessment and Section VI., Significance of Risk). In 
Section V.C., Risk Reduction, OSHA demonstrates the efficacy of the 
controls relied on in this proposed rule to reduce the risk of heat-
related injury and illness in the workplace. Employees working in 
workplaces without these controls are at higher risk of severe health 
outcomes from exposure to hazardous heat.
    On October 27, 2021, OSHA published in the Federal Register an 
advance notice of proposed rulemaking (ANPRM) for Heat Injury and 
Illness Prevention in Outdoor and Indoor Work Settings (86 FR 59309). 
The ANPRM outlined key issues and challenges in occupational heat-
related injury and illness prevention and aimed to collect evidence, 
data, and information critical to informing how OSHA proceeds in the 
rulemaking process. The ANPRM included background information on 
injuries, illnesses, and fatalities due to heat, underreporting, scope, 
geographic region, and inequality in exposures and outcomes. The ANPRM 
also covered existing heat injury and illness prevention efforts 
including OSHA's efforts, the National Institute for Occupational 
Safety and Health (NIOSH) criteria documents, State standards, and 
other standards.
    OSHA received 965 unique public comments, which largely supported 
the need for continued rulemaking. The agency then worked with the 
National Advisory Committee on Occupational Safety and Health (NACOSH) 
to assemble a Heat Injury and Illness Prevention Work Group. The Work 
Group was tasked with evaluating stakeholder input to the ANPRM and 
developing recommendations on potential elements of a proposed heat 
injury and illness prevention standard. The Work Group presented its 
recommendations on potential elements of a proposed heat injury and 
illness prevention standard for consideration by the full NACOSH 
committee. On May 31, 2023, NACOSH amended the report to ask OSHA to 
include a model written plan and then unanimously voted to submit the 
Work Group's recommendations to the Secretary of Labor.
    In accordance with the requirements of the Small Business 
Regulatory Enforcement Fairness Act (SBREFA), OSHA next convened a 
Small Business Advocacy Review (SBAR) Panel in August 2023. The Panel, 
comprised of members from the Small Business Administration's (SBA) 
Office of Advocacy, OSHA, and OMB's Office of Information and 
Regulatory Affairs, heard comments directly from Small Entity 
Representatives (SERs) on the potential impacts of a heat-specific 
standard. The Panel received advice and recommendations from the SERs 
and reported its findings and recommendations to OSHA. OSHA has taken 
the SER's comments and the Panel's findings and recommendations into 
consideration in the development of this proposed rule (see Section 
VIII.F., Initial Regulatory Flexibility Analysis).
    In accordance with 29 CFR parts 1911 and 1912, OSHA also consulted 
with and considered feedback from the Advisory Committee on 
Construction

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Safety and Health (ACCSH). On April 24, 2024, the Committee unanimously 
passed a motion recommending that OSHA proceed expeditiously with 
proposing a standard on heat injury and illness prevention. In 
addition, in accordance with Executive Order 13175, Consultation and 
Coordination with Indian Tribal Governments, 65 FR 67249 (Nov. 6, 
2000), OSHA held a listening session on May 15, 2024, with Tribal 
representatives regarding this Heat Injury and Illness Prevention in 
Outdoor and Indoor Work Settings rulemaking and provided an opportunity 
for the representatives to offer feedback.
    The proposed rule is a programmatic standard that requires 
employers to create a heat injury and illness prevention plan to 
evaluate and control heat hazards in their workplace. It establishes 
requirements for identifying heat hazards, implementing engineering and 
work practice control measures at or above two heat trigger levels 
(i.e., an initial heat trigger and a high heat trigger), developing and 
implementing a heat illness and emergency response plan, providing 
training to employees and supervisors, and retaining records. The 
proposed rule would apply to all employers conducting outdoor and 
indoor work in all general industry, construction, maritime, and 
agriculture sectors, with some exceptions (see Section VII.A., 
Paragraph (a) Scope and Application). Throughout this document, OSHA 
seeks input on alternatives and potential exclusions.
    Organizations affected by heat hazards vary significantly in size 
and workplace activities. Accordingly, many of the provisions of the 
proposed standard provide flexibility for affected employers to choose 
the control measures most suited to their workplace. The flexible 
nature of the proposed rule may be particularly beneficial to small 
organizations with limited resources.
    Additionally, to determine whether the proposed rule is feasible 
for affected employers, and in accordance with Executive Orders 12866 
and 13563, the Regulatory Flexibility Act (RFA), and the Unfunded 
Mandates Reform Act (2 U.S.C 1501 et seq.), OSHA has prepared a 
Preliminary Economic Analysis (PEA), including an Initial Regulatory 
Flexibility Analysis (see Section VIII., Preliminary Economic Analysis 
and Initial Regulatory Flexibility Analysis). Supporting materials 
prepared by OSHA are available in the public docket for this 
rulemaking, Document ID OSHA-2021-0009, through regulations.gov.

II. Pertinent Legal Authority

A. Introduction

    In the Occupational Safety and Health Act, 29 U.S.C. 651 et seq., 
Congress authorized the Secretary of Labor (``the Secretary'') ``to set 
mandatory occupational safety and health standards applicable to 
businesses affecting interstate commerce'' (29 U.S.C. 651(b)(3); see 
Nat'l Fed'n of Indep. Bus. v. Dep't of Labor, 595 U.S. 109, 117 (2022) 
(per curiam); see also 29 U.S.C. 654(a)(2) (requiring employers to 
comply with OSHA standards)). Section 6(b) of the Act authorizes the 
promulgation, modification or revocation of occupational safety or 
health standards pursuant to detailed notice and comment procedures (29 
U.S.C. 655(b)).
    Section 3(8) of the Act defines a safety or health standard as a 
standard which requires conditions, or the adoption or use of one or 
more practices, means, methods, operations, or processes ``reasonably 
necessary or appropriate'' to provide safe or healthful employment and 
places of employment (29 U.S.C. 652(8)). A standard is reasonably 
necessary or appropriate within the meaning of section 3(8) when a 
significant risk of material harm exists in the workplace and the 
standard would substantially reduce or eliminate that workplace risk 
(see Indus. Union Dep't, AFL-CIO v. Am. Petroleum Inst., 448 U.S. 607 
(1980) (``Benzene'')). OSHA's authority extends to, for example, 
removing workers from environments where workplace hazards exist (see, 
e.g., United Steelworkers of America v. Marshall, 647 F.2d 1189, 1228-
38 (D.C. Cir. 1981); 29 CFR 1910.1028(i)(8); 29 CFR 1910.1024(l); cf. 
Whirlpool Corp. v. Marshall, 445 U.S. 1, 12 (1980) (upholding 
regulation allowing employees to refuse dangerous work in certain 
circumstances because ``[t]he Act does not wait for an employee to die 
or become injured.'').
    In addition to the requirement that each standard address a 
significant risk, standards must also be technologically feasible (see 
UAW v. OSHA, 37 F.3d 665, 668 (D.C. Cir. 1994)). A standard is 
technologically feasible when the protective measures it requires 
already exist, when available technology can bring the protective 
measures into existence, or when that technology is reasonably likely 
to develop (see Am. Iron and Steel Inst. v. OSHA, 939 F.2d 975, 980 
(D.C. Cir. 1991)).
    Finally, a standard must be economically feasible (see Forging 
Indus. Ass'n v. Secretary of Labor, 773 F.2d 1436, 1453 (4th Cir. 
1985)). A standard is economically feasible if industry can absorb or 
pass on the costs of compliance without threatening its long-term 
profitability or competitive structure (see American Textile Mfrs. 
Inst., Inc., 452 U.S. 490, 530 n.55 (``Cotton Dust'')). Each of these 
requirements is discussed further below.

B. Significant Risk

    As noted above, OSHA's workplace safety and health standards must 
address a significant risk of material harm that exists in the 
workplace (see Benzene, 448 U.S. at 614-15). The agency's risk 
assessments are based on the best available evidence, and its final 
conclusions are made only after considering all information in the 
rulemaking record. Reviewing courts have upheld the Secretary's 
significant risk determinations where supported by substantial evidence 
and ``a reasoned explanation for [their] policy assumptions and 
conclusions'' (Bldg & Constr. Trades Dep't v. Brock, 838 F.2d 1258, 
1266 (D.C. Cir. 1988) (``Asbestos II'')).
    The Supreme Court in Benzene explained that ``[i]t is the agency's 
responsibility to determine, in the first instance, what it considers 
to be a `significant' risk'' (Benzene, 448 U.S. at 655). The Court 
declined to ``express any opinion on the . . . difficult question of 
what factual determinations would warrant a conclusion that significant 
risks are present which make promulgation of a new standard reasonably 
necessary or appropriate'' (Benzene, 448 U.S. at 659). The Court 
stated, however, that the substantial evidence standard applicable to 
OSHA's significant risk determination (see 29 U.S.C. 655(b)(f)) does 
not require the agency ``to support its finding that a significant risk 
exists with anything approaching scientific certainty'' (Benzene, 448 
U.S. at 656). Rather, OSHA may rely on ``a body of reputable scientific 
thought'' to which ``conservative assumptions in interpreting the 
data'' may be applied, ``risking error on the side of overprotection'' 
(Benzene, 448 U.S. at 656). The D.C. Circuit has further explained that 
OSHA may thus act with a pronounced bias towards worker safety in 
making its risk determinations (Asbestos II, 838 F.2d at 1266). The 
Supreme Court also recognized that the determination of what 
constitutes ``significant risk'' is ``not a mathematical straitjacket'' 
and will be ``based largely on policy considerations'' (Benzene, 448 
U.S. at 655 & n.62).
    Once OSHA makes its significant risk finding, the standard it 
promulgates must be ``reasonably necessary or appropriate'' to reduce 
or eliminate that

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risk (29 U.S.C. 652(8)). In choosing among regulatory alternatives, 
however, ``[t]he determination that [one standard] is appropriate, as 
opposed to a marginally [more or less protective] standard, is a 
technical decision entrusted to the expertise of the agency'' (Nat'l 
Mining Ass'n v. Mine Safety and Health Admin., 116 F.3d 520, 528 (D.C. 
Cir. 1997) (analyzing a Mine Safety and Health Administration standard 
under the Benzene significant risk standard)).

C. Feasibility

    The statutory mandate to consider the feasibility of the standard 
encompasses both technological and economic feasibility; OSHA has 
performed these analyses primarily on an industry-by-industry basis 
(United Steelworkers of Am., AFL-CIO-CLC v. Marshall, 647 F.2d 1189, 
1264, 1301 (D.C. Cir. 1980) (``Lead I'')). The agency has also used 
application groups, defined by common tasks, as the structure for its 
feasibility analyses (Pub. Citizen Health Research Grp. v. OSHA, 557 
F.3d 165, 177-79 (3d Cir. 2009)). The Supreme Court has broadly defined 
feasible as ``capable of being done'' (Cotton Dust, 452 U.S. at 509-
10).
I. Technological Feasibility
    A standard is technologically feasible if the protective measures 
it requires already exist, can be brought into existence with available 
technology, or can be created with technology that can reasonably be 
expected to be developed (Lead I, 647 F.2d at 1272; Amer. Iron & Steel 
Inst. v. OSHA, 939 F.2d 975, 980 (D.C. Cir. 1991) (``Lead II'')). 
Courts have also interpreted technological feasibility to mean that a 
typical firm in each affected industry or application group will 
reasonably be able to implement the requirements of the standard in 
most operations most of the time (see Public Citizen v. OSHA, 557 F.3d 
165, 170-71 (3d Cir. 2009); Lead I, 647 F.2d at 1272; Lead II, 939 F.2d 
at 990)). OSHA's standards may be ``technology forcing,'' so long as 
the agency gives an industry a reasonable amount of time to develop new 
technologies to comply with the standard. Thus, OSHA is not bound by 
the ``technological status quo'' (Lead I, 647 F.2d at 1264).
II. Economic Feasibility
    In addition to technological feasibility, OSHA is required to 
demonstrate that its standards are economically feasible. A reviewing 
court will examine the cost of compliance with an OSHA standard ``in 
relation to the financial health and profitability of the industry and 
the likely effect of such costs on unit consumer prices'' (Lead I, 647 
F.2d at 1265 (citation omitted)). As articulated by the D.C. Circuit in 
Lead I, ``OSHA must construct a reasonable estimate of compliance costs 
and demonstrate a reasonable likelihood that these costs will not 
threaten the existence or competitive structure of an industry, even if 
it does portend disaster for some marginal firms'' (Lead I, 647 F.2d at 
1272). A reasonable estimate entails assessing ``the likely range of 
costs and the likely effects of those costs on the industry'' (Lead I, 
647 F.2d at 1266). As with OSHA's consideration of scientific data and 
control technology, however, the estimates need not be precise (Cotton 
Dust, 452 U.S. at 528-29 & n.54), as long as they are adequately 
explained.
    OSHA standards satisfy the economic feasibility criterion even if 
they impose significant costs on regulated industries so long as they 
do not cause massive economic dislocations within a particular industry 
or imperil the very existence of the industry (Lead II, 939 F.2d at 
980; see also Lead I, 647 F.2d at 1272; Asbestos I, 499 F.2d. at 478). 
As with its other legal findings, OSHA ``is not required to prove 
economic feasibility with certainty, but is required to use the best 
available evidence and to support its conclusions with substantial 
evidence'' (Lead II, 939 F.2d at 980-81 (citing Lead I, 647 F.2d at 
1267)).
    In addition to determining economic feasibility, OSHA estimates the 
costs and benefits of its proposed and final rules to ensure compliance 
with other requirements such as those in Executive Orders 12866 and 
13563.

D. High Degree of Employee Protection

    Safety standards must provide a high degree of employee protection 
to be consistent with the purpose of the Act (see Control of Hazardous 
Energy Sources (Lockout/Tagout) Final Rule, Supplemental Statement of 
Reasons, 58 FR 16612, 16614-15 (March 30, 1993)). OSHA has 
preliminarily determined that this proposed standard is a safety 
standard because the health effects associated with exposure to 
occupational heat are generally acute. As explained in Section IV., 
Health Effects, the proposed standard aims to address the numerous 
acute health effects of occupational exposure to hazardous heat. These 
include, among other things, heat stroke, heat exhaustion, heat 
syncope, and physical injuries (e.g., falls) due to fatigue or other 
heat-related impairments. These harms occur after relatively short-term 
exposures to hazardous heat and are typically apparent at the time of 
the exposure or shortly thereafter. Consequently, the link between 
these harms and heat exposures is also often apparent and they do not 
implicate the concerns about latent, hidden harms that underly health 
standards (see Benzene, 448 U.S. at 649 n. 54; UAW v. OSHA, 938 F.2d 
1310, 1313 (D.C. Cir. 1991) (``Lockout/Tagout I''); National Grain & 
Feed Ass'n v. OSHA, 866 F.2d 717, 733 (5th Cir. 1989) (``Grain 
Dust'')).
    Finally, although OSHA acknowledges that there is growing evidence 
occupational exposure to hazardous heat may lead to some chronic 
adverse health outcomes like chronic kidney disease, much of the 
science in this area is still developing (see Section IV., Health 
Effects). In any event, the agency expects that addressing the acute 
hazards posed by heat would also protect workers from potential chronic 
health outcomes by reducing workers' overall heat strain.

III. Background

A. Introduction

    The Occupational Safety and Health Administration (OSHA) is 
proposing a new standard to protect outdoor and indoor workers from 
hazardous heat in the workplace. OSHA promulgates and enforces 
occupational safety and health standards under authority granted by the 
Occupational Safety and Health (OSH) Act of 1970 (29 U.S.C. 651 et 
seq.).
    In the absence of a Federal occupational heat standard, five States 
have issued heat injury and illness prevention regulations to protect 
employees exposed to heat hazards in the workplace: Minnesota (Minn. R. 
5205.0110 (1997)); California (Cal. Code of Regs. tit. 8, section 3395 
(2005)); Oregon (Or. Admin. R. 437-002-0156 (2022); Or. Admin. R. 437-
004-1131 (2022)); Colorado (7 Colo. Code Regs. section 1103-15 (2022)); 
and Washington (Wash. Admin. Code sections 296-62-095 through 296-62-
09560; 296-307-097 through 296-307-09760 (2023)). Although Minnesota 
was the first State to adopt a standard covering employees exposed to 
indoor environmental heat conditions, California was the first State to 
adopt a standard covering employees exposed to outdoor environmental 
heat conditions. Washington, Oregon, and Colorado have since enacted 
similar regulations to California's, requiring employers to implement 
controls and monitor for signs and symptoms of heat-related injury or 
illness, among other requirements. In 2023, California proposed a new 
standard that would cover indoor work environments (California, 2023). 
In 2024, Maryland

[[Page 70702]]

published a proposed standard that would cover both outdoor and indoor 
work environments (Maryland, 2024).
    Workers in many industries are at risk for heat-related injury and 
illness stemming from hazardous heat exposure (see Section V.A., Risk 
Assessment). While the general population may be able to avoid and 
limit prolonged heat exposure, workers across a wide range of indoor 
and outdoor settings often are required to work through shifts with 
prolonged heat exposure. Some workplaces have heat generation from 
industrial processes and expose workers to sources of radiant heat, 
such as ovens and furnaces. Additionally, employers may not take 
adequate steps to protect their employees from exposure to hazardous 
heat (e.g., not providing rest breaks in cool areas). Many work 
operations also require the use of personal protective equipment (PPE) 
that can reduce the worker's heat tolerance because it can decrease the 
body's ability to cool down. Workers may also face pressure, or 
incentivization through pay structures, to push through and continue 
working despite high heat exposure, which can increase the risk of 
heat-related injury and illness (Billikopf and Norton, 1992; Johansson 
et al., 2010; Spector et al., 2015; Pan et al., 2021).
    OSHA uses several terms related to excessive heat exposure 
throughout this proposal. Heat stress is the combined load of heat that 
a person experiences from sources of heat (i.e., metabolic heat and the 
environment) and heat retention (e.g., from clothing or personal 
protective equipment). Heat strain refers to the body's response to 
heat stress (American Conference of Governmental Industrial Hygienists 
(ACGIH), 2023). Heat-related illness means adverse clinical health 
outcomes that occur due to heat exposure, such as heat exhaustion or 
heat stroke. Heat-related injury means an injury linked to heat 
exposure, such as a fall or cut. OSHA sometimes refers to these 
collectively as ``heat-related injuries and illnesses.''

B. Need for Proposal

    Occupational heat exposure affects millions of workers in the 
United States. Each year, thousands of workers experience heat-related 
injuries and illnesses, and some of these cases result in fatalities 
(BLS, 2023b; BLS, 2024c). OSHA has relied on the General Duty Clause of 
the OSH Act (discussed further below), as well as enforcement emphasis 
programs and hazard alerts and other guidance, to protect workers and 
inform employers of their legal obligations. However, a standard 
specific to heat-related injury and illness prevention would more 
clearly set forth enforceable employer obligations and the measures 
necessary to effectively protect employees from hazardous heat.
    Workers in both outdoor and indoor work settings without adequate 
climate controls are at risk of hazardous heat exposure. In addition to 
weather-related heat, certain heat-generating processes, machinery, and 
equipment (e.g., hot tar ovens, furnaces) can cause hazardous heat 
exposure when cooling measures are not in place. An evaluation of 66 
heat-related illness enforcement investigations from 2011-2016 found 
heat-related injuries and illnesses, including fatalities, occurring in 
both outdoor (n=34) and indoor (n=29) work environments (Tustin et al., 
2018a). Excessive heat exacerbates existing health conditions like 
asthma, diabetes, kidney failure, and heart disease, and can cause heat 
stroke and death if not treated properly and promptly. Some groups may 
be more likely to experience adverse health effects from heat, such as 
pregnant workers (NIOSH, 2024), while others are disproportionately 
exposed to hazardous levels of heat, such as workers of color in 
essential jobs, who are more often employed in work settings with a 
high risk of hazardous heat exposure (Gubernot et al., 2015).
    The Bureau of Labor Statistics (BLS), in its Census of Fatal 
Occupational Injuries, documented 1,042 U.S. worker deaths due to 
occupational exposure to environmental heat from 1992-2022, with an 
average of 34 fatalities per year during that period (BLS, 2024c). In 
2022 alone, BLS reported 43 work-related deaths due to environmental 
heat exposure (BLS, 2024c). The BLS Annual Survey of Occupational 
Injuries and Illnesses (SOII) estimates 33,890 work-related heat 
injuries and illnesses involving days away from work from 2011-2020, 
which is an average of 3,389 injuries and illnesses occurring each year 
during this period (BLS, 2023b).
    Workers across hundreds of industries are at risk for hazardous 
heat exposure and resulting heat-related injuries and illnesses. From 
January 1, 2017, to December 31, 2022, 1,054 heat-related injuries, 
illnesses, and fatalities were reported to and investigated by OSHA, 
including 625 heat-related hospitalizations and 211 heat-related 
fatalities, as well as 218 heat-related injuries and illnesses that did 
not result in hospitalization. During this time, hospitalizations 
occurred most frequently in construction, manufacturing, and postal and 
delivery service. Fatalities were most frequently reported in 
construction, landscaping, agriculture, manufacturing, and postal and 
delivery service (as identified by 2-digit NAICS codes).
    However, as explained in Section V.A., Risk Assessment, these 
statistics likely do not capture the true magnitude and prevalence of 
heat-related injuries, illnesses, and fatalities. Recent studies 
demonstrate significant undercounting of occupational injuries and 
illnesses by both the BLS SOII and OSHA's enforcement data. One reason 
for this undercounting is that the BLS SOII only reports the number of 
heat-related injuries and illnesses involving days away from work and 
thus does not capture the full picture of heat-related injuries and 
illnesses. An examination of workers' compensation claims in 
California, which include more than only cases involving days away from 
work, identified 3 to 6 times the number of annual heat-related illness 
and injury cases than reported by BLS SOII (Heinzerling et al., 2020). 
In addition, evidence has shown significant underreporting as employers 
and employees are disincentivized from reporting injuries and illnesses 
due to several factors, including potential increases in workers' 
compensation costs or impacts on the employer's reputation, or an 
employee's fear of retaliation or lack of awareness of their right to 
speak out about workplace conditions (BLS, 2020b).
    Heat-related injuries and illnesses may present unique challenges 
to surveillance efforts. As the nature of heat-related symptoms (e.g., 
headache, fatigue) vary, some cases may be attributed to other 
illnesses rather than heat (as discussed in Section IV., Health 
Effects). Furthermore, heat is not always identified as a contributing 
factor to fatality, as heat exposure may exacerbate existing medical 
conditions and medical professionals may not witness the symptoms and 
events preceding death (Luber et al., 2006).
    Finally, exposure to heat can interfere with routine occupational 
tasks and impact workers' psychomotor and mental performance, which can 
lead to workplace injuries. Particularly, heat can impair performance 
of job tasks related to complex cognitive function (Hancock and 
Vasmatzidis, 2003; Piil et al., 2017) and reduce decision making 
abilities (Ramsey et al., 1983; Xiang et al., 2014a) and productivity 
(Foster et al., 2021). A growing body of evidence has demonstrated that 
heat-induced impairments may result in significant occupational 
injuries that are not currently factored into official statistics for 
heat-related cases (Spector et al., 2016; Calkins et al., 2019; 
Dillender, 2021; Park et al., 2021). See Section V.A., Risk Assessment, 
for further

[[Page 70703]]

discussion on underreporting of heat-related injuries, illnesses, and 
fatalities.
    While a significant percentage of heat-related incidents are 
unreported, OSHA's investigations of reported heat-related fatalities 
point to many gaps in employee protections. OSHA has identified the 
following circumstances in its review of 211 heat-related fatality 
investigations from 2017-2022: employees left alone by employers after 
symptoms started; employers not providing adequate medical attention to 
employees with symptoms; employers preventing employees from taking 
rest breaks; employers not providing water on-site; employers not 
providing on-site access to shade; employers not providing cooling 
measures on-site; and employers not having programs to acclimatize 
employees to hot work environments (https://www.osha.gov/fatalities). 
OSHA has relied on multiple mechanisms to protect employees from 
hazardous heat, however, OSHA's efforts to prevent the aforementioned 
circumstances have been met with challenges without a heat-specific 
standard (as discussed in Section III.C.III., OSHA's Heat-Related 
Enforcement).
    Many U.S. States run their own OSHA-approved State Plans (e.g., 
State heat standards, voluntary consensus standards) (see Section 
III.D., Other Standards), however OSHA has preliminarily determined 
that this standard is still needed to protect workers from the 
persistent and serious hazards posed by occupational heat exposure. As 
explained in Section VI., Significance of Risk, OSHA has preliminarily 
determined that a significant risk of material harm from occupational 
exposure to hazardous heat exists, and issuance of this standard would 
substantially reduce that risk. Therefore, to more clearly set forth 
employer obligations and the measures necessary to more effectively 
protect employees from hazardous heat, and reduce the number and 
frequency of occupational injuries, illness, and fatalities caused by 
exposure to hazardous heat, OSHA is proposing a Federal standard for 
Heat Injury and Illness Prevention for Outdoor and Indoor Work 
Settings.

C. Events Leading to the Proposal

I. History of Heat as a Recognized Occupational Hazard
    Heat exposure has long been recognized as an occupational hazard. 
For example, in the United States, the occupational hazards associated 
with the construction of the Hoover Dam between 1931 and 1935 brought 
attention to the effects of heat on worker health. The Bureau of 
Reclamation reported that 14 dam workers and two others residing in the 
work area died from ``heat prostration'' in 1931 (Bureau of 
Reclamation, 2015). According to a local newspaper, temperatures at the 
dam site that summer reached 140 [deg]F in the sun and 120 [deg]F in 
the shade (Turk, 2018; Rogers, 2012). In response to the extreme heat 
of the summer and other unsafe working conditions, the Industrial 
Workers of the World convinced Hoover Dam workers to strike over safety 
concerns (Turk, 2018; Rogers, 2012). Six Companies, the conglomerate of 
companies hired by the Bureau of Reclamation to construct most of the 
dam, was forced to make concessions, including protections against HRI 
such as providing potable water in dormitories, bringing ice water to 
workers at their work sites, and adding first aid stations closer to 
the job site (Rogers, 2012). The heat-related deaths that occurred 
during 1931 also prompted Harvard University researchers from the 
Harvard Fatigue Laboratory to travel to the Hoover Dam and study the 
relationship between hot, dry temperatures, physical performance, and 
heart rate (Turk, 2018).
    Heat-related illnesses were identified as a major concern for the 
U.S. military in the 1940s and 1950s. Between 1942 and 1944, 198 
soldiers died of heat stroke at U.S.-based training camps, 157 of which 
did not have a known history of cardiac diseases or other conditions 
that may predispose them to heat illness (Schickele, 1947, p. 236). 
This led to investigations of the environmental conditions at the time 
of these deaths, and eventually to the development of wet bulb globe 
temperature (WBGT) to measure heat stress (Yaglou and Minard, 1957; 
Minard, 1961; Department of the Army, 2022; Department of the Navy, 
2023).
    Research on the effects of occupational heat exposure continued in 
the 1960s, as researchers conducted trials examining the physiological 
effects of work at various temperatures (e.g., Lind, 1963). Findings 
from these trials would eventually underpin the American Conference of 
Governmental Industrial Hygienists (ACGIH) Threshold Limit Value (TLV), 
as well as the National Institute of Occupational Safety and Health 
(NIOSH) Recommended Exposure Limit (REL) (Dukes-Dobos and Henschel, 
1973). ACGIH first proposed guidelines for a TLV in 1971, which were 
later adopted in 1974.
    Heat was recognized as a preventable workplace hazard in the 
legislative history of the OSH Act. Senator Edmund Muskie submitted a 
letter in support of the OSH Act into the Congressional record on 
behalf of ``a distinguished group of citizens, including a former 
Secretary of Labor and several noted scientists.'' (Senate Debate on S. 
2193, Nov. 16, 1970), reprinted in Legislative History of the 
Occupational Safety and Health Act of 1970, pp. 513-14 (1971) 
(Committee Print) (``Leg. Hist.''). The letter states, ``Most 
industrial diseases and accidents are preventable. Modern technological 
and medical sciences are capable of solving the problems of noise, 
dust, heat, fumes, and toxic substances in the plants. However, 
existing legislation in this area does not begin to meet the problems'' 
(Leg. Hist., pp. 513-14).
    In 1972, just two years after promulgation of the OSH Act, NIOSH 
first recommended a potential OSHA heat standard in its Criteria for a 
Recommended Standard (NIOSH, 1972). This criteria document, issued 
under the authority of section 20(a) of the OSH Act, recommended an 
OSHA standard based on a critical review of scientific and technical 
information. In response, an OSHA Standards Advisory Committee on Heat 
Stress was appointed in 1973 and presented recommendations for a 
standard for work in hot environments in 1974. At the time, 12 of 15 
members of the advisory committee agreed that occupational heat stress 
warranted a standard (Ramsey, 1975).
    NIOSH's criteria document for a recommended standard has since been 
updated in 1986 (NIOSH, 1986) and again in 2016 (NIOSH, 2016). The 2016 
criteria document recommends various provisions to protect workers from 
heat stress, including rest breaks, hydration, shade, acclimatization 
plans, and worker training (NIOSH, 2016). The 2016 criteria document 
also recommends that no worker be ``exposed to combinations of 
metabolic and environmental heat greater than'' the recommended alert 
limit (RAL) for unacclimatized workers or the recommended exposure 
limit (REL) for acclimatized workers). The document recommends that 
environmental heat be assessed with measurements of WBGT (NIOSH, 2016).
    A detailed report of the history of heat as a recognized 
occupational hazard is available in the docket (ERG, 2024a). The report 
summarizes historical documentation of occupational heat-related 
illness beginning in ancient times and from the eighteenth century 
through the regulatory interest in the twentieth century.

[[Page 70704]]

II. OSHA's Heat Injury and Illness Prevention Efforts
    In 2011, OSHA issued a memorandum to inform regional administrators 
and State Plan designees of inspection guidance for heat-related 
illnesses (OSHA, 2011). That same year, OSHA launched the Heat Illness 
Prevention Campaign (https://www.osha.gov/heat) to build awareness of 
prevention strategies and tools for employers and workers to reduce 
occupational heat-related illness. In its original form, the Campaign 
delivered a message of ``Water. Rest. Shade.'' The agency updated 
Campaign materials in 2021 to recognize both indoor and outdoor heat 
hazards, as well as the importance of protecting new and returning 
workers from hazardous heat with an acclimatization period.
    In addition, OSHA maintains on its website a Heat Topics page on 
workplace heat exposure (https://www.osha.gov/heat-exposure/), which 
provides additional information and resources. The page provides 
information on planning and supervision in hot work environments, 
identification of heat-related illness and first aid, information on 
prevention such as training, calculating heat stress and controls, 
personal risk factors, descriptions of other heat standards and case 
study examples of situations where workers developed heat-related 
illness. OSHA and NIOSH also co-developed a Heat Safety Tool Smartphone 
App for both Android and iPhone devices (see www.osha.gov/heat/heat-app). The app provides outdoor, location-specific temperature, 
humidity, and heat index (HI) readings. Measurements for indoor work 
sites must be collected and manually entered into the app by the user 
for accurate calculations. The app also provides relevant information 
on identifying signs and symptoms of heat-related illness and steps to 
prevent heat-related injuries and illnesses. Despite the strengths and 
reach of the Campaign, Heat Topics page, and Heat Safety Tool App, 
these guidance and communication materials are not legally enforceable 
requirements.
III. OSHA's Heat-Related Enforcement
    Without a specific standard governing hazardous heat conditions at 
workplaces, the agency currently enforces section 5(a)(1) (the General 
Duty Clause) of the OSH Act against employers that expose their workers 
to this recognized hazard. Section 5(a)(1) states that employers have a 
general duty to furnish to each of their employees ``employment and a 
place of employment which are free from recognized hazards that are 
causing or are likely to cause death or serious physical harm'' to 
employees (29 U.S.C. 654(a)(1)). To prove a violation of the General 
Duty Clause, OSHA must establish--in each individual case--that: (1) 
the employer failed to keep the workplace free of a hazard to which its 
employees were exposed; (2) the hazard was recognized; (3) the hazard 
was causing or likely to cause death or serious injury; and (4) a 
feasible means to eliminate or materially reduce the hazard existed 
(see, e.g., A.H. Sturgill Roofing, Inc., 2019 O.S.H. Dec. (CCH) ] 
[thinsp]33712, 2019 WL 1099857 (No. 13-0224, 2019)).
    OSHA has relied on the General Duty Clause to cite employers for 
heat-related hazards for decades (see, e.g., Duriron Co., 11 BNA OSHC 
1405, 1983 WL 23869 (No. 77-2847, 1983), aff'd, 750 F.2d 28 (6th Cir. 
1984)). According to available OSHA enforcement data, between 1986 and 
2023, Federal OSHA issued at least 348 hazardous heat-related citations 
under the General Duty Clause. Of these citations, 85 were issued 
between 1986-2000 (OSHA, 2024b). Citations were identified using 
multiple queries of OSHA enforcement data and then manually reviewed to 
ensure the inclusion of only citations due to heat exposure and no 
other exposures (e.g., burns or explosions). Several keywords were 
utilized to filter the data for inclusion (e.g., ``heat,'' ``heat 
stress,'' ``heat illness,'' ``WBGT'') and exclusion (e.g., 
``explosion,'' ``flash,'' ``electrical burn,'' ``fire''). Due to 
limitations of the data set on which OSHA relied, OSHA did not have 
access to violation text descriptions of citations issued before the 
mid-1980s and thus did not determine how many are related to heat 
exposure prior to this time period. Additionally, over half of the 
citations from 1986-1989 are missing violation text descriptions, which 
likely resulted in an undercount of heat-related citations.
    OSHA has used its general inspection authority (29 U.S.C. 657) to 
target heat-related injuries and illnesses in various Regional Emphasis 
Programs (REPs). OSHA enforcement emphasis programs focus the agency's 
resources on particular hazards or high-hazard industries (see Marshall 
v. Barlow's, Inc., 436 U.S. 307, 321 (1978) (affirming OSHA's use of an 
administrative plan containing specific neutral criteria to focus 
inspections)). OSHA's Region VI regional office, located in Dallas, TX, 
has a heat-related special REP (OSHA, 2019). This region covers Texas, 
New Mexico, Oklahoma, Arkansas, and Louisiana. OSHA's Region IX 
regional office, located in San Francisco, CA, also has a heat-related 
REP (OSHA, 2022). This region covers American Samoa, Arizona, 
California, Guam, Hawaii, Nevada, and the Northern Mariana Islands. 
These REPs allow field staff to conduct heat illness inspections of 
outdoor work activities on days when the high temperature is forecasted 
to be above 80 [deg]F.
    On September 1, 2021, OSHA issued updated Inspection Guidance for 
Heat-Related Hazards, which established a new enforcement initiative to 
protect employees from heat-related injuries and illnesses while 
working in hazardous hot indoor and outdoor environments (OSHA, 2021). 
The guidance provided that days when the heat index exceeds 80 [deg]F 
would be considered heat priority days. It announced that enforcement 
efforts would be increased on heat priority days for a variety of 
indoor and outdoor industries, with the aim of identifying and 
mitigating potential hazards and preventing heat-illnesses before they 
occur.
    In April 2022, OSHA launched a National Emphasis Program (NEP) to 
protect employees from heat-related hazards and resulting injuries and 
illnesses in outdoor and indoor workplaces. The NEP expanded the 
agency's ongoing heat-related injury and illness prevention initiatives 
and campaign by setting forth a targeted enforcement component and 
reiterating its compliance assistance and outreach efforts. The NEP 
targets specific industries expected to have the highest exposures to 
heat-related hazards and resulting illnesses and deaths. This approach 
is intended to encourage early interventions by employers to prevent 
illnesses and deaths among workers during high heat conditions (CPL 03-
00-024). As of June 26, 2024, OSHA has conducted 5,038 Heat NEP Federal 
inspections. More than 1,229 of these were initiated by complaints and 
117 were due to the occurrence of a fatality or catastrophe. As a 
result of these inspections, OSHA issued 56 General Duty Clause 
citations and 736 Hazard Alert Letters (HALs). Inspections occurred 
across various industries (as identified by 2-digit NAICS codes) 
including construction, which had the highest number of inspections, as 
well as manufacturing, maritime, agriculture, transportation, 
warehousing, food services, waste management, and remediation services.
    On July 27, 2023, OSHA issued a heat hazard alert to remind 
employers of their obligation to protect workers against heat injury 
and illness in outdoor and indoor workplaces. The alert highlights what 
employers can and

[[Page 70705]]

should be doing to protect employees. It also serves to remind 
employees of their rights, including protections against retaliation. 
In addition, the alert highlights steps OSHA is currently taking to 
protect workers and directs employers, employees, and the public to 
OSHA resources, including guidance and fact sheets on heat.
    OSHA's efforts to protect employees from hazardous heat conditions 
using the General Duty Clause, although important, have limitations 
leaving many workers vulnerable to heat-related hazards. For example, 
the Commission has struggled to determine exactly what conditions 
create a recognized heat hazard under the General Duty Clause, and has 
therefore suggested the necessity of a standard (see, A.H. Sturgill 
Roofing, Inc., 2019 OSHD (CCH) ] [thinsp]33712, 2019 WL 1099857, at *2-
5 and n.8 (No. 13-0224, 2019) (``The Secretary's failure to establish 
the existence of an excessive heat hazard here illustrates the 
difficulty in addressing this issue in the absence of an OSHA 
standard.''); U.S. Postal Service, 2023 OSHD (CCH) ] 33908, 2023 WL 
2263313, at *3 n.7 (Nos. 16-1713, 16-1872, 17-0023,17-0279, 2023) 
(noting Commissioner Laihow's opinion that ``A myriad of factors, such 
as the geographical area where the work is being performed and the 
nature of the tasks involved, can impact'' whether excessive heat is 
present, and indicating that a standard is therefore necessary to 
define the hazard).
    Under the General Duty Clause, OSHA cannot require abatement before 
proving in an enforcement proceeding that specific workplace conditions 
are hazardous; whereas a standard would establish the existence of the 
hazard at the rulemaking stage, thus allowing OSHA to identify and 
require specific abatement measures without having to prove the 
existence of a hazard in each case (see Sanderson Farms, Inc. v. Perez, 
811 F.3d 730, 735 (5th Cir. 2016) (``Since OSHA is required to 
determine that there is a hazard before issuing a standard, the 
Secretary is not ordinarily required to prove the existence of a hazard 
each time a standard is enforced.'')). Given OSHA's burden under the 
General Duty Clause, it is currently difficult for OSHA to ensure 
necessary abatement before employee lives and health are unnecessarily 
endangered. Further, under the General Duty Clause OSHA must largely 
rely on expert witness testimony to prove both the existence of a 
hazard and the availability of feasible abatement measures that will 
materially reduce or eliminate the hazard in each individual case (see, 
e.g., Industrial Glass, 15 BNA OSHC 1594, 1992 WL 88787, at *4-7 (No. 
88-348, 1992)).
    Moreover, as OSHA has noted in similar contexts, standards have the 
advantage of providing greater clarity to employers and employees of 
the measures required to protect employees and are developed with the 
benefit of information gathered in the notice and comment process (see 
86 FR 32376, 32418 (Jun. 21, 2021) (COVID-19 Healthcare ETS); 56 FR 
64004, 64007 (Dec. 6, 1991) (Bloodborne Pathogens Standard)).
    OSHA currently has other existing standards that, while applicable 
to some issues related to hazardous heat, have not proven to be 
adequate in protecting workers from exposure to hazardous heat. For 
example, OSHA's Recordkeeping standard (29 CFR 1904.7) requires 
employers to record and report injuries and illnesses that meet 
recording criteria. Additionally, the agency's Sanitation standards (29 
CFR 1910.141, 1915.88, 1917.127, 1926.51, and 1928.110) require 
employers to provide potable water readily accessible to workers. While 
these standards require that drinking water be made available in 
``sufficient amounts,'' they do not specify quantities, and employers 
are not required to encourage workers to frequently hydrate on hot 
days.
    OSHA's Safety Training and Education standard (29 CFR 1926.21) 
requires employers in the construction industry to train employees in 
the recognition, avoidance, and prevention of unsafe conditions in 
their workplaces. OSHA's PPE standards (29 CFR 1910.132, 1915.152, 
1917.95, and 1926.28) require employers to conduct a hazard assessment 
to determine the appropriate PPE to be used to protect employees from 
the hazards identified in the assessment. However, hazardous heat is 
not specifically identified as a hazard for which workers need training 
or PPE, complicating the application of these requirements to hazardous 
heat.
IV. Rulemaking Activities Leading to This Proposal
    OSHA has received multiple petitions to promulgate a heat injury 
and illness prevention standard, including in 2018 from Public Citizen, 
on behalf of approximately 130 organizations (Public Citizen et al., 
2018). OSHA has also been urged by members of Congress to initiate 
rulemaking for a Federal heat standard, as well as by the Attorneys 
General of several States in 2023.
    On October 27, 2021, OSHA published an advance notice of proposed 
rulemaking (ANPRM) for Heat Injury and Illness Prevention in Outdoor 
and Indoor Work Settings in the Federal Register (86 FR 59309) 
(referred to as ``the ANPRM'' hereafter). The ANPRM outlined key issues 
and challenges in occupational heat-related injury and illness 
prevention and aimed to collect evidence, data, and information 
critical to informing how OSHA proceeds in the rulemaking process. The 
ANPRM included background information on injuries, illnesses, and 
fatalities due to heat, underreporting, scope, geographic region, and 
inequality in exposures and outcomes. The ANPRM also covered existing 
heat injury and illness prevention efforts, including OSHA's efforts, 
the NIOSH criteria documents, State standards, and other standards. The 
initial public comment period was extended and closed on January 26, 
2022. In response to the ANPRM, OSHA received 965 unique comments. The 
comments covered several topics, including the scope of a standard, 
heat stress thresholds for workers across various industries, heat 
acclimatization planning, and heat exposure monitoring, as well as the 
nature, types, and effectiveness of controls that may be required as 
part of a standard.
    Following the publication of the ANPRM, OSHA presented topics from 
the ANPRM and updates on the heat rulemaking to several stakeholders, 
including several trade associations, the Office of Advocacy of the 
Small Business Administration's (SBA's Office of Advocacy) Labor Safety 
Roundtable (November 19, 2021), and NIOSH National Occupational 
Research Agenda (NORA) councils, including the Construction Sector 
Council (November 17, 2021), Landscaping Safety Workgroup (January 12, 
2022), and Oil and Gas Extraction Sector (April 7, 2022).
    On May 3, 2022, OSHA held a virtual public stakeholder meeting on 
the agency's ``Initiatives to Protect Workers from Heat-Related 
Hazards.'' A total of over 1,300 people attended the virtual meeting, 
and the recorded video has been viewed over 3,500 times (see 
www.youtube.com/watch?v=Ud29WsnsOw8) as of June 2024. The six-hour 
meeting provided stakeholders an opportunity to learn about and comment 
on efforts OSHA is taking to protect workers from heat-related hazards 
and ways the public can participate in the agency's rulemaking process.
    OSHA also established a Heat Injury and Illness Prevention Work 
Group of the National Advisory Committee on Occupational Safety and 
Health (NACOSH) to support the agency's rulemaking and outreach 
efforts. The Work Group was tasked with reviewing

[[Page 70706]]

and developing recommendations on OSHA's heat illness prevention 
guidance materials, evaluating stakeholder input, and developing 
recommendations on potential elements of any proposed heat injury and 
illness prevention standard. On May 31, 2023, the Work Group presented 
its recommendations on potential elements of a proposed heat injury and 
illness prevention standard for consideration by the full NACOSH 
committee. The Work Group recommended that any proposed heat injury and 
illness prevention standard include: a written exposure control plan/
heat illness prevention plan; training; environmental monitoring; 
workplace control measures; acclimatization; worker participation; and 
emergency response (Document ID OSHA-2023-0003-0007). After 
deliberations, NACOSH amended the report to ask OSHA to include a model 
written plan and then submitted its recommendations to the Secretary of 
Labor (Document ID OSHA-2023-0003-0012).
    As an initial rulemaking step, OSHA convened a Small Business 
Advocacy Review Panel (SBAR Panel) on August 25, 2023, in accordance 
with the Regulatory Flexibility Act (RFA) (5 U.S.C. 601 et seq.), as 
amended by the Small Business Regulatory Enforcement Act (SBREFA) of 
1996. This SBAR Panel consisted of members from OSHA, SBA's Office of 
Advocacy, and the Office of Information and Regulatory Affairs (OIRA) 
in the White House Office of Management and Budget (OMB). The SBAR 
Panel identifies individual representatives of affected small entities, 
termed small entity representatives (SERs), which includes small 
businesses, small local government entities, and non-profits. This 
process enabled OSHA, with the assistance of SBA's Office of Advocacy 
and OIRA, to obtain advice and recommendations from SERs about the 
potential impacts of the regulatory options outlined in the regulatory 
framework and about additional options or alternatives to the 
regulatory framework that may alleviate those impacts while still 
meeting the objectives and requirements of the OSH Act.
    The SBAR Panel hosted six online meetings on September 9, 12, 13, 
14, 18, and 19, 2023, with participation from a total of 82 SERs from a 
wide range of industries. A final report containing the findings, 
advice, and recommendations of the SBAR Panel was submitted to the 
Assistant Secretary of Labor for Occupational Safety and Health on 
November 3, 2023, to help inform the agency's decision making with 
respect to this rulemaking (Document ID OSHA-2021-0009-1059).
    In accordance with 29 CFR parts 1911 and 1912, OSHA presented to 
the Advisory Committee on Construction Safety and Health (ACCSH) on its 
framework for a proposed rule for heat injury and illness prevention in 
outdoor and indoor work settings on April 24, 2024. The Committee then 
passed unanimously a motion recommending that OSHA proceed 
expeditiously with proposing a standard on heat injury and illness 
prevention. The Committee also recommended that OSHA consider the 
feedback and questions discussed by Committee members during the 
meeting in formulating the proposed rule (see the minutes from the 
meeting, Docket No. 2024-0002). OSHA has considered the Committee's 
feedback in the development of this proposal.
    In accordance with Executive Order 13175, Consultation and 
Coordination with Indian Tribal Governments, 65 FR 67249 (Nov. 6, 
2000), OSHA held a listening session with Tribal representatives 
regarding this Heat Injury and Illness Prevention in Outdoor and Indoor 
Work Settings rulemaking on May 15, 2024. OSHA provided an overview of 
the rulemaking effort and sought comment on what, if any, tribal 
implications would result from the rulemaking. A summary of the meeting 
and list of attendees can be viewed in the docket (DOL, 2024a).

D. Other Standards

    Various other organizations have also either identified the need 
for standards to prevent occupational heat-related injury and illness 
or published their own standards. In 2024, the American National 
Standards Institute/American Society of Safety Professionals A10 
Committee (ANSI/ASSP) published a consensus standard on heat stress 
management in construction and demolition operations. The International 
Organization for Standardization (ISO) also has a standard for 
evaluating heat stress: ISO 7243: Ergonomics of the thermal 
environments--Assessment of heat stress using the WBGT (wet bulb globe 
temperature) index (ISO, 2017). ISO 7243 uses WBGT values, along with 
metabolic rate, to assess hot environments, similar to ACGIH and NIOSH 
recommendations. Additional ISO standards address predicting sweat rate 
and core temperature (ISO 7933), and determining metabolic rate (ISO 
8996), physiological strain (ISO 9886), and thermal characteristics for 
clothing (ISO 9920). In 2021, the American Society for Testing and 
Materials (ASTM) finalized its Standard Guide for Managing Heat Stress 
and Heat Strain in Foundries (E3279-21) which establishes ``best 
practices for recognizing and managing occupational heat stress and 
heat strain in foundry environments.'' The standard outlines employer 
responsibilities and recommends elements for a ``Heat Stress and Heat 
Strain Management Program'' (ASTM, 2021).
    ACGIH has identified TLVs for heat stress (ACGIH, 2023). The TLVs 
utilize WBGT and take into consideration metabolic rate or workload 
categories. Additionally, ACGIH provides clothing adjustment factors 
which are added to the measured WBGT for certain types of work clothing 
to account for the impaired thermal regulation.
    The U.S. Armed Forces has developed extensive heat-related illness 
prevention and management strategies. The Warrior Heat and Exertion 
Related Events Collaborative is a tri-service group of military leaders 
focused on clinical, educational, and research efforts related to 
exercise and exertional heat-related illnesses and medical emergencies 
(HPRC, 2023). The U.S. Army has a Heat Center at Fort Benning which 
focuses on management, research, and prevention of heat-related illness 
and death (Galer, 2019). In 2023, the U.S. Army updated its Training 
and Doctrine Command (TRADOC) Regulation 350-29 addressing heat and 
cold casualties. The regulation includes requirements for rest and 
water consumption according to specific WBGT levels and work intensity 
(Department of the Army, 2023). The U.S. Navy has developed 
Physiological Heat Exposure Limit curves that are based on metabolic 
and environmental heat loads and represent the maximum allowable heat 
exposure limits, which were most recently updated in 2023. The Navy 
monitors WBGT and has guidelines based on these measurements, with 
physical training diminishing as WBGTs increase and all nonessential 
outdoor activity stopped when WBGTs exceed 90 [deg]F (Department of the 
Navy, 2023). The U.S. Marine Corps follows the Navy's guidelines for 
implementation of the Marine Corps Heat Injury Prevention Program 
(Commandant of the Marine Corps, 2002). In 2022, the U.S. Army and U.S. 
Air Force issued an update to their technical heat stress bulletin, 
which outlines measures to prevent indoor and outdoor heat-related 
illness in soldiers. The bulletin includes recommended acclimatization 
planning, work-rest cycles, fluid and electrolyte replacement, and 
limitations on work based on WBGT (Department of the Army, 2022).

[[Page 70707]]

    As of April 2024, five States have promulgated heat standards 
requiring employers in various industries and workplace settings to 
implement protections to reduce the risk of heat-related injuries and 
illnesses for their employees: California, Minnesota, Oregon, 
Washington, and Colorado. In addition, Maryland and California are 
currently engaged in rulemaking. State standards differ in the scope of 
coverage (see tables III-1 and 2). For example, Minnesota's standard 
covers only indoor workplaces. California and Washington standards 
cover only outdoor workplaces, although California's proposal would 
include coverage of indoor workplaces. Oregon's rule covers both indoor 
and outdoor workplaces. State rules also differ in the methods used for 
triggering protections against hazardous heat. Minnesota's standard 
considers the type of work being performed (light, moderate, or heavy) 
and provides WBGT trigger levels based on the type of work activity. 
California's heat-illness prevention protections go into effect at an 
ambient temperature of 80 [deg]F. Washington's rule also relies on 
ambient temperature readings combined with considerations for the 
breathability of workers' clothing. Oregon's rule uses a heat index 80 
[deg]F as a trigger.
    California, Washington, Colorado, and Oregon all have additional 
protections that are triggered by high heat. However, they differ as to 
the trigger for these additional protections. In California, high heat 
protections are triggered at an ambient temperature reading of 95 
[deg]F (and only apply in certain industries). In Washington, high heat 
protections are triggered at an ambient temperature reading of 90 
[deg]F. In Colorado, additional protections are triggered at an ambient 
temperature reading of 95 [deg]F or by other factors such as unhealthy 
air quality, length of workday, heaviness of clothing or gear, and 
acclimatization status. These additional protections only apply to the 
agricultural industry. Finally, in Oregon, high heat protections are 
triggered at a heat index of 90 [deg]F.
    All the State standards require training for employees and 
supervisors. All the State standards, except for Minnesota, require 
employers to provide at least one quart of water per hour for each 
employee, require some form of emergency response plan, include 
provisions related to acclimatization for workers, and require access 
to shaded break areas. Washington and Oregon require that employers 
provide training in a language that the workers understand. Similarly, 
California's standard requires that employers create a written heat-
illness prevention plan in English as well as in whatever other 
language is understood by the majority of workers at a given workplace. 
California also requires close monitoring of new employees for the 
first fourteen days and monitoring of all employees during a heat wave. 
Table III-1 below provides an overview of the provisions included in 
the existing and proposed State standards on heat injury and illness 
prevention. Table III-2 provides an overview of the additional 
provisions required when the high heat trigger is met or exceeded.

                                                            Table III-1--Initial Heat Triggers and Provisions in State Heat Standards
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                   Shade or
                                                Threshold          Provision of    cool-down    Rest breaks    Emergency   Acclimatization    Training     Heat illness prevention  Observation/
                                                                       water         means       if needed     response                                             plan             supervision
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                             General
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
California: Outdoor...................  80 [deg]F (Ambient) \1\..                                         ................  ............
Washington: Outdoor...................  80 [deg]F (Ambient), All                                           (accident        ............
                                         other clothing; 52                                                                                                prevention).
                                         [deg]F, Non-breathable
                                         clothes.
Colorado: Agriculture.................  80 [deg]F (Ambient)......                                         ........................     
California (proposal): Indoor.........  82 [deg]F (Ambient)......                                         ................  ............
Maryland (proposal): Indoor & Outdoor.  80 [deg]F (Heat Index)...              ............                       ................  ............
Minnesota: \2\ Indoor.................  86 [deg]F (WBGT), Light    ............  ............  ............  ............  ...............        ........................  ............
                                         work; 80 [deg]F,
                                         Moderate work; 77
                                         [deg]F, Heavy work.
Oregon: Indoor & Outdoor..............  80 [deg]F (Heat Index)...              ............                       ................  ............
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Some provisions, including water, emergency response, training, and heat illness prevention plan, apply to covered employers regardless of the temperature threshold.
\2\ Minnesota uses a 2-hour time-weighted average permissible exposure limit rather than a trigger.


                Table III-2--High Heat Triggers and Additional Provisions in State Heat Standards
----------------------------------------------------------------------------------------------------------------
                                                                                                     Assessment
                                    Threshold         Work-rest       Observation/      Pre-shift    and control
                                                      schedule         supervision      meetings    measures \1\
----------------------------------------------------------------------------------------------------------------
                                         Additional High Heat Provisions
----------------------------------------------------------------------------------------------------------------
California: Outdoor \2\.......  95 [deg]F          (only    ........        ............
                                 (Ambient).        agriculture).
Washington: Outdoor...........  90 [deg]F         ........  ........  ............  ............
                                 (Ambient).
Colorado: Agriculture.........  95 [deg]F         ........  covered in              ............
                                 (Ambient) or                        general
                                 other condition                     provisions
                                 \3\.                                above.
California (proposal): Indoor.  87 [deg]F         ................  ................  ............     
                                 (Ambient or
                                 Heat Index) or
                                 other
                                 conditions \4\.
Maryland (proposal): Indoor &   90 [deg]F (Heat   ........  ........  ............  ............
 Outdoor.                        Index).
Oregon: Indoor & Outdoor......  90 [deg]F (Heat   ........  ........  ............  ............
                                 Index).
----------------------------------------------------------------------------------------------------------------
\1\ Assessment and control measures include measuring temperature and heat index, identifying and evaluating all
  other environmental risk factors for heat illness, and using specified control measures to minimize the risk
  of heat illness.

[[Page 70708]]

 
\2\ High heat procedures apply in agriculture; construction; landscaping; oil and gas extraction; transportation
  or delivery of agricultural products, construction materials or other heavy materials, except for employment
  that consists of operating an air-conditioned vehicle and does not include loading or unloading.
\3\ Other conditions include unhealthy air quality, shifts over 12 hours, heavy clothing or gear required, or
  the employee is new or returning from absence.
\4\ Other conditions include wearing clothing that restricts heat removal, or working in a high radiant heat
  area, when the ambient temperature is at or above 82 [deg]F.

IV. Health Effects

A. Introduction

I. Health Effects of Occupational Heat Exposure
    Exposure to workplace heat can be seriously detrimental to workers' 
health and safety and, in some cases, can be fatal. Workplace heat 
contributes to heat stress, which is a person's total heat load (NIOSH, 
2016) from the following sources combined: (1) heat from the 
environment, including heat generated by equipment or machinery; (2) 
metabolic heat generated through body movement, which is proportional 
to one's relative level of exertion (Sawka et al., 1993; Astrand 1960); 
and (3) heat retained due to clothing or personal protective equipment 
(PPE), which is highly dependent on the breathability of the clothing 
and PPE worn (Bernard et al., 2017). Heat is routinely an occupation-
specific risk because, for example, workers may experience greater heat 
stress than non-workers, particularly when they are required to work 
through shifts with prolonged heat exposure, complete tasks that 
require physical exertion, and/or their employers do not take adequate 
steps to protect them from exposure to hazardous heat. In addition, 
many work operations require the use of PPE. PPE can increase heat 
stress and can reduce workers' heat tolerance by decreasing the body's 
ability to cool down. Workers may also face pressure, or 
incentivization through pay structures (e.g., piece-rate, bonuses), to 
work through hazardous heat. Pressure to produce results and be seen as 
a good worker can have a direct impact on worker self-care choices that 
impact health (Wadsworth et al., 2019). Pay structures and production 
quotas intended to motivate workers may also compromise worker safety 
(Iglesias-Rios et al., 2023). These pressures can increase their risk 
of heat-related injury and illness (Billikopf and Norton, 1992; 
Johansson et al., 2010; Spector et al., 2015; Pan et al., 2021). The 
body's response to heat stress is called heat strain (NIOSH, 2016). As 
the heat stress a person experiences increases, the body attempts to 
cool itself by releasing heat into the surrounding environment. If the 
body begins to acquire heat faster than it can release it, the body 
will store heat. As stored heat accumulates, the body can show signs of 
excessive heat strain, such as increased core temperature and heart 
rate, as well as symptoms of heat strain, such as sweating, dizziness, 
or nausea.
    Two large meta-analyses (n=2,409 and n=11,582) \1\ have confirmed 
that occupational heat exposure is associated with both signs and 
symptoms of heat strain (Ioannou et al., 2022; Flouris et al., 2018). 
In one, the authors found a high prevalence of heat strain (35%) among 
workers in hot conditions, defined by the authors as WBGT greater than 
26 [deg]C (78.8 [deg]F); they also found that workers in hot conditions 
were four times more likely to experience signs and symptoms of heat 
strain than workers in more moderate conditions (Flouris et al., 2018).
---------------------------------------------------------------------------

    \1\ In the Health Effects section, OSHA refers to statistics 
that were reported by authors when describing results from their 
research studies. These include the sample size (n), the odds ratio 
(OR), the confidence interval (CI), and the p-value (p). These 
statistics provide information about effect size, error, and 
statistical significance.
---------------------------------------------------------------------------

II. Literature Review for Health Effects Section
    OSHA conducted a non-systematic review of the medical and 
scientific literature to identify evidence on the relationship between 
heat exposure and illnesses and death. OSHA's literature review focused 
on meta-analyses, systematic reviews, and studies cited in NIOSH's 
Criteria for a Recommended Standard: Occupational Exposure to Heat and 
Hot Environments, published in 2016. OSHA separately searched for 
additional meta-analyses and systematic reviews that were not cited in 
the NIOSH Criteria document, including those that were published after 
the document was released (i.e., 2016 and on).
    OSHA also reviewed sentinel epidemiological evidence including 
observational, experimental, and randomized controlled studies. OSHA 
primarily reviewed epidemiological studies focusing on worker 
populations, athletes, and military members, but also included studies 
in non-worker populations where appropriate. For example, when there 
was limited occupation-specific research or data for some heat-related 
health effects, OSHA sometimes considered general population studies as 
they relate to understanding physiological mechanisms of heat-related 
illness, severity of an illness, and prognosis. In addition to the 
evidence of heat-related illnesses and deaths, OSHA reviewed a large 
body of evidence that evaluated the association of occupational heat 
exposure with workplace injuries such as falls, collisions, and other 
accidents. OSHA also reviewed evidence regarding individual factors 
such as age, medication use, and certain medical conditions that may 
affect one's risk for heat-related health effects.
III. Summary
    The best available evidence in the scientific and medical 
literature, as summarized in this Health Effects section, demonstrates 
that occupational heat exposure can result in death; illnesses, 
including heat stroke, heat exhaustion, heat syncope, rhabdomyolysis, 
heat cramps, hyponatremia, heat edema, and heat rash; and heat-related 
injuries, including falls, collisions, and other workplace accidents.

B. General Mechanisms of Heat-Related Health Effects

    This section briefly describes the mechanisms of heat-related 
health effects, i.e., how the body's physiological responses to heat 
exposure can lead to the heat-related health effects identified in 
OSHA's literature review. More detailed information about the 
mechanisms underpinning each specific heat-related health effect is 
described in the relevant subsections that follow.
    As explained above, occupational heat exposure contributes to heat 
stress. The resulting bodily responses are collectively referred to as 
heat strain (Cramer and Jay, 2016). The bodily responses included in 
heat strain serve to decrease stored heat by increasing heat loss to 
the environment to maintain a stable body temperature (NIOSH, 2016). 
When the brain recognizes that the body is storing heat, it activates 
the autonomic nervous system to initiate cooling (Kellogg et al., 1995; 
Wyss et al., 1974). Blood is shunted towards the skin and vasodilation 
begins, meaning that the blood vessels near the skin's surface become 
wider, thereby increasing blood flow near the surface of the skin 
(Kamijo et al., 2005; Hough and Ballantyne, 1899). The autonomic 
nervous system also triggers the body's sweat response, in which sweat 
glands release water to wet the skin (Roddie et al., 1957; Grant and 
Holling, 1938). These processes allow the body to cool in four ways: 
(1) radiation, i.e., when heat is released directly into the

[[Page 70709]]

surrounding air; (2) convection, i.e., when there is air movement that 
moves heat away from the body; (3) evaporation, i.e., when sweat on the 
skin diffuses into surrounding air (as clothing/PPE permits) and (4) 
conduction, i.e., when heat is directly transferred through contact 
with a cooler surface (e.g., wearing an ice-containing vest (Cramer and 
Jay, 2016; Leon and Kenefick, 2012)).
    Importantly, the extent of heat release through radiation, 
convection, and evaporation depends on environmental conditions such as 
the speed of air flow, temperature, and relative humidity (Clifford et 
al., 1959; Brebner et al., 1958). For example, when relative humidity 
is high, sweat is less likely to evaporate off the skin, which 
significantly reduces the cooling effect of evaporation. Additionally, 
when sweat remains on the skin and irritates the sweat glands, it can 
cause a condition known as heat rash, whereby itchy red clusters of 
pimples or blisters develop on the skin (DiBeneditto and Worobec, 1985; 
Sulzberger and Griffin, 1968).
    While the purpose of the sweat response is to cool the body, in 
doing so, it can deplete the body's stores of water and electrolytes 
(e.g., sodium [Na], potassium [K], chloride [Cl], calcium [Ca], and 
magnesium [Mg]) that are essential for normal bodily function 
(Shirreffs and Maughan, 1997). The condition resulting from abnormally 
low sodium levels is known as hyponatremia. When stores of electrolytes 
are depleted, painful muscle spasms known as heat cramps can occur 
(Kamijo and Nose, 2006). Additionally, depletion of the body's stored 
water causes dehydration, which is known to reduce the body's 
circulating blood volume (Trangmar and Gonzalez-Alonso, 2017; Dill and 
Costill, 1974).
    During vasodilation that happens as the body attempts to cool, 
blood can pool in areas of the body that are most subject to gravity, 
and fluid can seep from blood vessels causing noticeable swelling under 
the skin (known as heat edema). Upright standing would further 
encourage blood to pool in the legs, and thus, the heart has an even 
lower blood volume available for circulation (Smit et al., 1999). A 
large reduction in circulating blood volume will lead to (1) a 
continued rise in core body temperature, and (2) reduced blood flow to 
the brain, muscles, and organs. A rise in core body temperature and 
reduced blood flow to the brain can cause neurological disturbances, 
such as loss of consciousness, which are characteristic of heat stroke 
and heat syncope (Wilson et al., 2006; Van Lieshout et al., 2003). A 
rise in core body temperature and reduced blood flow to muscles can 
also cause extreme muscle fatigue (to the point of collapse) and muscle 
cell damage during exertion, which are characteristic of heat 
exhaustion and rhabdomyolysis, respectively (Torres et al., 2015; Nybo 
et al., 2014). Finally, a rise in core body temperature and reduced 
blood flow to organs can damage multiple vital organs (such as the 
heart, liver, and kidneys), which is often observed in heat stroke 
(Crandall et al., 2008; O'Donnell and Clowes, 1972). Heat stroke and 
rhabdomyolysis can lead to death if not treated properly and promptly.

C. Identifying Cases of Heat-Related Health Effects

    In its review of the scientific and medical literature on the 
health effects of occupational heat exposure, OSHA found several 
studies that relied upon coding systems, in which medical providers or 
other public health professionals identify fatalities and non-fatal 
cases of various illnesses and injuries, including heat-related 
illnesses and injuries (HRIs). The medical and scientific communities 
use data from these coding systems to study the incidence and 
prevalence of illnesses and injuries, including HRIs. In both this 
Health Effects section and Section V., Risk Assessment, OSHA relied on 
several studies that make use of data from these coding systems. A 
brief summary of each of the major coding systems is provided below.
I. International Statistical Classification of Diseases and Related 
Health Problems (ICD) Codes
    The International Statistical Classification of Diseases and 
Related Health Problems (ICD) System is under the purview of the World 
Health Organization (WHO), an international agency that, as the leading 
authority on health and disease, regularly publishes evidence-based 
guidelines to advance clinical practice and public health policy. The 
ICD System harmonizes the diagnosis of disease across many countries, 
and ICD codes are used routinely in the U.S. healthcare system by 
medical personnel to record diagnoses in patients' medical records, as 
well as to identify cause of death. These codes are utilized as part of 
a standardized system for recording diagnoses, as well as organizing 
and collecting data into public health surveillance systems. Each ICD 
code is a series of letters and/or numbers that corresponds to a highly 
specific medical diagnosis. Healthcare providers may record multiple 
ICD codes if an individual presents with multiple diagnoses. The ICD 
system has multiple codes that medical personnel can use when 
diagnosing HRIs.
    The ICD system was first developed in the 18th century and was 
adopted under the purview of the World Health Organization (WHO) in 
1948 (Hirsch et al., 2016). Since then, the ICD system has been revised 
11 times--ICD-11 was released in 2022. However, because the ICD-11 
system has not yet been implemented in the United States, many of the 
epidemiological studies cited throughout this Health Effects section 
used the ICD-9 and ICD-10 systems to survey heat-related deaths and 
HRIs. Table IV-1 provides a list of heat-related ICD-9 and ICD-10 
codes.

  Table IV--1--ICD-9 and ICD-10 Codes for Heat-Related Health Effects *
------------------------------------------------------------------------
               ICD-9 code                     ICD-10 code equivalent
------------------------------------------------------------------------
992 Effects of heat and light..........  T67 Effects of heat and light.
992.0 Heatstroke and sunstroke.........  T67.0 Heatstroke and sunstroke.
992.1 Heat syncope.....................  T67.1 Heat syncope.
992.2 Heat cramps......................  T67.2 Heat cramp.
992.3 Heat exhaustion, anhydrotic......  T67.3 Heat exhaustion,
                                          anhydrotic.
992.4 Heat exhaustion due to salt        T67.4 Heat exhaustion due to
 depletion.                               salt depletion.
992.5 Heat exhaustion, unspecified.....  T67.5 Heat exhaustion,
                                          unspecified.
992.6 Heat fatigue, transient..........  T67.6 Heat fatigue, transient.
992.7 Heat edema.......................  T67.7 Heat edema.
992.8 Other effects of heat and light..  T67.8 Other effects of heat and
                                          light.
992.9 Effects of heat and light,         T67.9 Effects of heat and
 unspecified.                             light, unspecified.
E900 Accident caused by excessive heat.  NA.

[[Page 70710]]

 
E900.0 Accident caused by excessive      X30 Exposure to excessive
 heat due to weather conditions.          natural heat.
E900.1 Accidents due to excessive heat   W92 Exposure to excessive heat
 of man-made origin.                      of man-made origin.
E900.9 Accidents due to excessive heat   X30 Exposure to excessive
 of unspecified origin.                   natural heat.
------------------------------------------------------------------------
Note: The above heat-related codes exclude X32 Exposure to sunlight and
  W89 Exposure to man-made radiation, among others.
* These ICD codes are specific to heat as indicated by the names of the
  codes. There are additional codes that can be associated with
  diagnosed heat illness but may not be specific to heat-related illness
  which are not included here but may be included in text where relevant
  (e.g., M62.82 for rhabdomyolysis and E87.1 for hypo-osmolality and
  hyponatremia).

    Various surveillance systems exist to track documentation of ICD 
codes. For example, the CDC leverages ICD-10 codes to collect nearly 
real-time data on heat-related deaths and HRIs through the National 
Syndromic Surveillance System (NSSP). The CDC also uses ICD-10 codes to 
collect annual data on heat-related deaths and HRIs, then reports these 
data via the National Vital Statistics System (NVSS) and National 
Center for Health Statistics (NCHS). Additionally, all branches of the 
U.S. Armed Forces (i.e., Army, Navy, Air Force, and Marine Corps) use 
ICD-10 codes to document HRIs among service members in the Defense 
Medical Surveillance System (DMSS). The US Army also uses ICD-10 codes 
to document HRIs in the Total Army Injury and Health Outcomes Database 
(TAIHOD) (Bell et al., 2004).
II. Occupational Illness and Injury Classification System (OIICS) Codes
    The U.S. Bureau of Labor Statistics (BLS) is a Federal agency, 
housed in the Department of Labor, that collects and analyzes data on 
the U.S. economy and workforce. In 1992, BLS developed the Occupational 
Illness and Injury Classification System (OIICS) to harmonize reporting 
of injuries and illnesses that affect U.S. workers. The OIICS is 
similar to the ICD system. Each OIICS code is a series of numbers that 
specifies a diagnosis (referred to as the nature of an illness or 
injury, or a ``nature code'') and event(s) leading to an illness or 
injury (referred to as an ``event code''). OIICS was updated in 2010 
(Version 2.0), and again in 2022 (Version 3.0); Version 3.0 is the most 
up to date version (https://www.bls.gov/iif/definitions/occupational-injuries-and-illnesses-classification-manual.htm; BLS, 2023e). The 
OIICS system has multiple codes that can be used when identifying 
occupational HRIs. Table IV-2 provides a list of heat-related OIICS 
codes (nature and event codes).

 Table IV--2--OIICS Codes (Version 3.0) for Heat-Related Health Effects
                                [dagger]
------------------------------------------------------------------------
 
-------------------------------------------------------------------------
Nature Codes:
    172 Effects of heat and light.
    1720 Effects of heat--unspecified.
    1721 Heat stroke, syncope.
    1722 Heat exhaustion, fatigue.
    1729 Effects of heat--not elsewhere classified.
    2893 Prickly heat, heat rash, and other disorders of the sweat
     glands including ``miliaria rubra''.
Event Codes:
    53 Exposure to temperature extremes.
    530 Exposure to temperature extremes--unspecified.
    531 Exposure to environmental heat.
    5310 Exposure to environmental heat--unspecified.
    5311 Exposure to environmental heat--indoor.
    5312 Exposure to environmental heat--outdoor.
------------------------------------------------------------------------
[dagger] Some of the data OSHA relies on uses older versions of OIICS
  codes (Versions 1 and 2) but the major categories for heat-related
  incidents did not change significantly between versions.

    Through a combination of survey staff and a specialized automated 
coding system, BLS applies OIICS codes to data collected through their 
worker safety and health surveillance systems, the Census of Fatal 
Occupational Injuries (CFOI) and the Survey of Occupational Injuries 
and Illnesses (SOII), to identify and document occupational heat-
related deaths and occupational HRIs, respectively. Researchers have 
also relied on this system for identifying occupational HRIs (e.g., 
Spector et al., 2016). However, BLS data does not currently specify 
discrete codes for all HRIs described in this health effects section. 
The CFOI is a cooperative program between the Federal Government and 
the States that relies on various administrative records, including 
death certificates, to accurately produce counts of fatal work injuries 
(BLS, 2012). The CFOI examines all cases marked ``At work'' on the 
death certificate, and the CFOI database relies on the death 
certificate (among other sources) to ascertain the cause(s) of death. 
Further details about BLS reporting using OIICS codes, as well as rates 
of HRIs, can be found in Section V., Risk Assessment.
III. Limitations
    A limitation to relying on these coding systems to identify heat-
related fatalities and HRIs is underreporting. Numerous studies have 
found that HRIs are likely vastly underreported (see Section V., Risk 
Assessment). Reasons for the likely underreporting include 
underreporting of illness and injuries by workers to their employers 
(Kyung et al., 2023), underreporting of injuries and illnesses by 
employers to BLS and OSHA (Wuellner and Phipps, 2018; Fagan and 
Hodgson, 2017), underutilization of workers' compensation insurance 
(Fan et al., 2006; Bonauto et al., 2010), influence of structural 
factors and work culture on workers perceptions about seeking help 
(Wadsworth et al., 2019; Iglesias-Rios, 2023), and difficulties with 
determining heat-related causes of death (e.g., Luber et al., 2006; 
Pradhan et al., 2019). As a result, there are likely many heat-related 
fatalities and cases of HRIs that are not

[[Page 70711]]

captured in these coding systems. For a more detailed discussion of 
underreporting, see Section V., Risk Assessment.
IV. Summary
    As demonstrated by these coding systems, in which medical providers 
or other public health professionals assign one or more codes to 
identify a heat-related fatality or HRI, it is well accepted in the 
medical and scientific communities that heat exposure, including 
occupational heat exposure, can result in death and HRIs. Indeed, in 
its review of the best available scientific and medical literature on 
the health effects of occupational heat exposure, OSHA identified 
several studies that relied upon data from these coding systems to 
determine the incidence or prevalence of heat-related deaths and HRIs 
in workers. OSHA relies on these studies in both this Health Effects 
section and Section V., Risk Assessment, of this preamble to the 
proposed rule.

D. Heat-Related Deaths

I. Introduction
    Heat is the deadliest weather phenomenon in the United States (NWS, 
2022). Heat as a cause of death is widely recognized in the medical and 
scientific communities. Studies investigating relationships between 
heat and mortality have long demonstrated positive associations between 
heat exposure and increased all-cause mortality (e.g., Weinberger et 
al., 2020; Basu and Samet, 2002; Whitman et al., 1997). As explained 
below, the connection between heat exposure, the body's physiological 
responses, and death (i.e., heat-related death mechanisms) is clearly 
established. Exposure to occupational heat can be fatal. According to 
BLS's CFOI, occupational heat exposure has killed 1,042 U.S. workers 
between 1992-2022 (BLS, 2024c).
II. Physiological Mechanisms
    Death caused by exposure to heat can occur in occupational settings 
if the worker's body is not able to adequately cool in response to heat 
exposure or if treatment for symptoms of heat-related illness is not 
provided promptly. Nearly all body systems can be negatively affected 
by heat exposure. Mora et al. (2017) systematically reviewed 
mechanistic studies on heat-related deaths and identified five harmful 
physiological mechanisms triggered by heat exposure that can lead to 
death: ischemia (inadequate blood flow), heat cytotoxicity (damage to 
and breakdown of cells), inflammatory response (inflammation that 
disrupts cell and organ function), disseminated intravascular 
coagulation (widespread dysfunction of blood clotting mechanisms), and 
rhabdomyolysis (breakdown of muscle tissue). These mechanisms, with the 
exception of rhabdomyolysis, are associated with the development of 
heat stroke. Rhabdomyolysis, which is a potentially fatal illness 
resulting from the breakdown of muscle tissue, can also occur in 
conjunction with or in the absence of heat stroke. For a more detailed 
discussion on rhabdomyolysis, see Section IV.H., Rhabdomyolysis. Mora 
et al. (2017) also identified seven vital organs that can be critically 
impacted by heat exposure--the brain, heart, kidneys, lungs, pancreas, 
intestines, and liver. Across the five identified mechanisms and seven 
vital organs, Mora et al. (2017) found medical evidence for twenty-
seven pathways whereby physiological mechanisms triggered by heat 
exposure could lead to organ failure and fatality.
    The most common cause of heat-related occupational deaths is heat 
stroke. Heat stroke is a potentially fatal dysregulation of multiple 
physiological processes and organ systems resulting in widespread organ 
damage. Heat stroke is typically marked by significant elevation in 
core body temperature and cognitive impairment due to central nervous 
system damage. The physiological mechanisms involved in the development 
and progression of heat stroke are discussed in more detail in Section 
IV.E., Heat Stroke.
III. Determining Heat as a Cause of Death
    The identification of deaths caused by heat exposure can take place 
in a few different ways. Healthcare professionals may identify heat-
related deaths in medical settings. For example, a heat-related death 
may be identified if an individual experiencing heat stroke presents to 
an emergency room and then later dies. The heat-related nature of the 
death should be documented by the healthcare professional in the chief 
complaint field during medical history taking and selection of relevant 
ICD diagnosis codes. The ICD system allows for identification of heat 
as either an underlying cause of death or a significant contributing 
condition. The ICD-10 instruction manual defines underlying cause as 
``(a) the disease or injury which initiated the train of morbid events 
leading directly to death, or (b) the circumstances of the accident or 
violence which produced the fatal injury'' (WHO, 2016, p. 31). A 
significant contributing condition is defined as a condition that 
``contributed to the fatal outcome, but was not related to the disease 
or condition directly causing death'' (WHO, 2004, p. 24).
    Medical examiners or coroners can also identify heat as a cause of 
death or significant condition contributing to death during death 
investigations, which should be noted on the deceased individual's 
death certificate. The National Association of Medical Examiners 
(NAME), a professional organization for medical examiners, forensic 
pathologists, and medicolegal affiliates and administrators, defines 
``heat-related death'' as ``a death in which exposure to high ambient 
temperature either caused the death or significantly contributed to 
it'' (Donoghue et al., 1997). This definition was developed in an 
effort to standardize the way in which heat-related deaths were 
identified and documented on death certificates. According to the NAME 
definition, cause is ascertained based on circumstances of the death, 
investigative reports of high environmental temperature (e.g., a known 
heat wave), or a pre-death temperature >=105 [deg]F. Cause is also 
indicated in cases where the person may have a lower body temperature 
due to attempted cooling measures, but where the individual had a 
history of mental status changes and specific toxicological findings of 
elevated muscle and liver enzymes. Heat may be designated as a 
``significant contributing condition'' if: (1) ``antemortem body 
temperature cannot be established but the environmental temperature at 
the time of collapse was high''; and/or (2) heat stress exacerbated a 
pre-existing disease, in which case heat and the pre-existing disease 
would be listed as the cause and significant contributing condition, 
respectively, or vice versa. Importantly, Donoghue et al. note ``The 
diagnosis of heat-related death is based principally on investigative 
information; autopsy findings are nonspecific.'' (Donoghue et al., 
1997). While this definition is the official definition of this 
professional organization, other definitions or processes for 
determining whether or not a death is heat-related may be used.
    Additionally, there are processes in place to identify and document 
deaths that are work-related. Death certificates include a field that 
can be checked for ``injury at work'' (Russell and Conroy, 1991). 
Further, work-related fatalities due to heat are identified and 
documented through the CFOI (for more details, see Section IV.C., 
Overview of ICD and OIICS Codes for Heat-Related Health Effects).

[[Page 70712]]

IV. Occupational Heat-Related Deaths
    Occupational heat exposure has led to worker fatalities in both 
indoor and outdoor work settings and across a variety of industries, 
occupations, and job tasks (Petitti et al., 2013; Arbury et al., 2014; 
Gubernot et al., 2015; NIOSH, 2016; Harduar Morano and Watkins, 2017). 
BLS's CFOI identified 1,042 U.S. worker deaths due to heat exposure 
between 1992 and 2022, with an average of 34 fatalities per year during 
that period (BLS, 2024c). Between 2011 and 2022, BLS reports 479 worker 
deaths (BLS, 2024c). During the latest three years for which BLS 
reports data (2020-2022), there was an average of 45 work-related 
deaths due to exposure to environmental heat per year (BLS, 2024c). 
However, for the reasons explained in Section V., Risk Assessment, 
these statistics likely do not capture the true magnitude and 
prevalence of heat-related fatalities because of underreporting.
    There are numerous case studies documenting the circumstances under 
which occupational heat exposure led to death among workers. For 
example, in three NIOSH Fatality Assessment and Control Evaluations 
(FACE) investigations of worker fatalities, workers died of heat stroke 
after not receiving prompt treatment upon symptom onset (NIOSH, 2004; 
NIOSH, 2007; NIOSH, 2015). Another case report of a farmworker who died 
due to heat stroke indicates that confusion the worker experienced as a 
result of heat exposure may have played a role in his ability to seek 
help (Luginbuhl et al., 2008). Additional case reports show workers 
have collapsed and later died while working alone, such as in mail 
delivery (Shaikh, 2023), and that worker distress has been interpreted 
as drug use as opposed to symptoms of heat illness (Alsharif, 2023).
V. Summary
    OSHA's review of the scientific and medical literature indicates 
that occupational heat exposure can and does cause death. The 
physiological mechanisms by which heat exposure can result in death are 
clearly established in the literature, and heat exposure being a cause 
of death is widely recognized in the medical and scientific 
communities. Indeed, occupational surveillance data demonstrates that 
numerous work-related deaths from occupational heat exposure occur 
every year.

E. Heat Stroke

I. Introduction
    Among HRIs, the most serious and deadly illness from occupational 
heat exposure is heat stroke. NIOSH (2016) defines heat stroke as ``an 
acute medical emergency caused by exposure to heat from an excessive 
rise in body temperature [above 41.1 [deg]C (106 [deg]F)] and failure 
of the [body's] temperature-regulating mechanism.'' When this happens, 
an individual's central nervous system is affected, which can result in 
a sudden and sustained loss of consciousness preceded by symptoms 
including vertigo, nausea, headache, cerebral dysfunction, bizarre 
behavior, and excessive body temperature (NIOSH 2016).
    Because progression of symptoms varies and involves central nervous 
system function, it may be difficult for individuals, or those they are 
with, to know when they are experiencing serious heat illness or to 
understand that they need urgent medical care (Alsharif, 2023). If not 
treated promptly, early symptoms of heat stroke may progress to 
seizures, coma, and death (Bouchama et al., 2022). Thus, heat stroke is 
often referred to as a life-threatening form of hyperthermia (i.e., 
elevated core body temperature) because it can cause damage to multiple 
organs such as the liver and kidneys. Of note, the term ``stroke'' in 
``heat stroke'' is a misnomer in that it does not involve a blockage or 
hemorrhage of blood flow to the brain.
    There are two types of heat stroke: classic heat stroke (CHS) and 
exertional heat stroke (EHS). CHS can occur without any activity or 
physical exertion, whereas EHS occurs as a result of physical activity. 
CHS typically occurs in environmental conditions where ambient 
temperature and humidity are high and is most often reported during 
heat waves (Bouchama et al., 2022). It is most likely to affect young 
children and the elderly (Laitano et al., 2019). Studies have found 
that EHS can occur with any amount of physical exertion, even within 
the first 60 minutes of exertion (Epstein and Yanovich, 2019; Garcia et 
al., 2022). Additionally, EHS can occur in healthy individuals who 
would otherwise be considered low risk performing physical activity, 
regardless of hot or cool environmental conditions (Periard et al., 
2022; Epstein et al., 1999).
    Cases of heat stroke can be identified in a few ways. Medical 
personnel who make a formal diagnosis of heat stroke record the 
corresponding ICD code in the patient's medical record. Medical 
examiners also identify heat stroke as a cause of death or significant 
condition contributing to death and note it on the deceased 
individual's death certificate.
II. Physiological Mechanisms
    Heat stroke happens when the body is under severe heat stress and 
is unable to dissipate excessive heat to keep the body temperature at 
37 [deg]C (98.6 [deg]F), resulting in an elevated core body temperature 
(Epstein and Yanovich, 2019). The hallmark characteristics of heat 
stroke are: (1) central nervous system (CNS) dysfunction, including 
encephalopathy (i.e., brain dysfunction manifesting as irrational 
behavior, confusion, coma, or convulsions); and (2) damage to multiple 
organs, including the kidneys, liver, heart, pancreas, gastrointestinal 
tract, as well as the circulatory system. There are three accepted 
mechanisms through which heat exposure can cause CNS dysfunction and/or 
multi-organ damage (Bouchama et al., 2022; Garcia et al., 2022; Iba et 
al., 2022). All three mechanisms share a common origin: heat exposure 
contributes to excessive heat stress, which results in hyperthermia.
    One mechanism of heat stroke is reduced cerebral blood velocity 
(CBV) (an indicator of blood flow to the brain) that results in 
orthostatic intolerance (i.e., the inability to remain upright without 
symptoms) (Wilson et al., 2006). As individuals experience whole body 
heating, CBV is reduced and cerebral vascular resistance (the ratio of 
carbon dioxide stimulus to cerebral blood flow) increases. These 
changes ultimately contribute to reduced cerebral perfusion (flow of 
blood from the circulatory system to cerebral tissue) and blood flow, 
as well as orthostatic intolerance (Wilson et al., 2006).
    Another mechanism is damage to the vascular endothelium. 
Hyperthermia can damage or kill cells in the lining of blood vessels, 
known as the vascular endothelium. The body responds to vascular 
endothelium damage through a process called disseminated intravascular 
coagulation (DIC). DIC is characterized by two processes: (1) tiny 
clots form in the tissues of multiple organs, and (2) bleeding occurs 
at the sites of those tiny clots. DIC is extremely damaging and results 
in injury to organs (Bouchama and Knochel, 2002). Namely, DIC limits 
the delivery of oxygen and nutrients to several organs including the 
brain, heart, kidneys, and liver. Thus, DIC can result in both CNS 
dysfunction and multi-organ damage. Additionally, damage to the 
vascular endothelium makes it more permeable and creates an imbalance 
in the substances that control blood clotting,

[[Page 70713]]

which promotes abnormal and increased blood clotting (Bouchama and 
Knochel, 2002; Wang et al., 2022).
    A third mechanism is damage to the cells in the lining of the gut, 
known as the gut epithelium. Hyperthermia can alter the cell membranes' 
permeability (Roti Roti et al., 2008), or directly cause cells to die 
(Bynum et al., 1978). In either case, cells in the gut epithelium will 
leak endotoxins into the blood, a process known as endotoxemia. When 
these endotoxins circulate throughout the body, the immune system 
aggressively responds by activating cells to fight infection and 
inflammation, known as systemic inflammatory response syndrome (SIRS) 
(Leon and Helwig, 2010). The presence of endotoxins, as well as the 
body's aggressive immune response, can cause serious multi-organ damage 
(Epstein and Yanovich, 2019; Wang et al., 2022). In particular, the 
liver is usually one of the first organs to be damaged and is often 
what causes a heat stroke death (Wang et al., 2022).
III. Occupational Heat Stroke
    Heat stroke is life-threatening and can severely impair workers' 
safety and health (Lucas et al., 2014). A study of work-related HRIs in 
Florida using hospital data reported that, during the warm seasons from 
May through October between 2005 through 2012, heat stroke was the 
primary diagnosis in 91% (21 of 23) of deaths. In total, they reported 
160 cases of work-related heat stroke (Harduar Morano and Watkins, 
2017). Analyses of heat stroke among military members indicate that 
roughly 73% of EHS patients require hospitalization for at least two 
days (Carter et al., 2007).
IV. Treatment and Recovery
    Heat stroke is a serious medical emergency that requires immediate 
rest, cooling, and usually hospitalization. Prognosis for heat stroke 
is highly dependent on how quickly heat stroke is recognized and how 
quickly an affected worker can be cooled. When an affected person can 
be diagnosed early and cooled rapidly, the prognosis is generally good. 
For example, rapid cooling within one hour of presentation of symptoms 
of CHS was found to reduce the mortality rate from 33% to 15% (Vicario 
et al., 1986). For EHS, cooling the body below 104 [deg]F within 30 
minutes of collapse is associated with very good outcomes (Casa et al., 
2012; Casa et al., 2015). The authors also reported that they were 
unaware of any cases of fatalities among EHS victims where it was 
recorded that the body was cooled below 104 [deg]F within 30 minutes of 
collapse (Casa et al., 2012).
    Comparably, others have found that the risk of morbidity and 
mortality from heat stroke increases as treatment is delayed (Demartini 
et al., 2015; Schlader et al., 2022). Schlader et al. (2022) found that 
a delay in cooling can result in tissue damage, multi-organ 
dysfunction, and eventually death. Similarly, Zeller et al. (2011) 
found in their retrospective cohort study that patients who did not 
receive early or immediate cooling had worse outcomes, such as more 
severe forms of disease or death, although their study design does not 
allow for conclusions regarding causality (Zeller et al., 2011). 
Khogali and Weiner's (1980) case study report on 18 cases of heat 
stroke found that 72% of the patients took between 30-90 minutes to 
cool, whereas the other 28% were resistant to cooling, taking two to 
five hours to reach 38 [deg]C (100.4 [deg]F). This means that there is 
variation in how individuals respond to heat stroke treatment and that 
some individuals will respond quicker to treatment than others. Prompt 
treatment is likely even more critical for the individuals who take 
longer to cool.
    Data from the general population also demonstrate the serious 
nature of heat stroke. One analysis of nationwide data estimated that 
nearly 55% of emergency department visits for heat stroke required 
hospitalization and roughly 3.5% of patients died in the emergency 
department or at the hospital (Wu et al., 2014). This study also found 
that heat stroke medical emergencies are more severe than other non-
heat-related emergencies, with a 2.6-fold increase in admission rate 
and a 4.8-fold increase in case fatality compared to those other 
conditions (Wu et al., 2014).
    Complete recovery for individuals who are affected by heat stroke 
may require time away from work. Some research suggests the length of 
recovery time and the need for time away from work is based on how long 
a person was at or above the critical core body temperature of 41 
[deg]C (105.8 [deg]F), and how long it takes for biomarkers in blood to 
normalize (McDermott et al., 2007). Relevant biomarkers include those 
for acute liver dysfunction, myolysis (the breakdown of muscle tissue), 
and other organ system biomarkers (Ward et al., 2020; Schlader et al., 
2022).
    Guidelines for military personnel and athletes suggest that it may 
be weeks or months before a worker who has suffered heat stroke can 
safely return to work or perform the same level of work they did before 
suffering heat stroke. U.S. military members have clear return-to-work 
protocols post-heat stroke where members are assigned grades of 
functional capacity in six areas: physical capacity or stamina, upper 
extremities, lower extremities, hearing and ears, eyes, and psychiatric 
functioning (O'Connor et al., 2007). For example, when a soldier/airman 
experiences heat stroke, they automatically receive a reduced function 
capacity grade status in physical capacity. This also results in an 
automatic referral to a medical examination board. Soldiers and airmen 
are not cleared to return to duty until their laboratory results 
normalize, and even then, their status remains a trial of duty. If the 
individual has not exhibited any heat intolerance after three months, 
they are returned to a normal work schedule. However, maximal exertion 
and significant heat exposure remains prohibited for these individuals. 
If a military member experiences any heat intolerance during the period 
of restriction, or subsequent resumption to normal duty, a referral to 
the physical examination board for a hearing regarding their health 
status is required (O'Connor et al., 2007).
    The U.S. Navy has its own set of guidelines, which does not 
distinguish between heat exhaustion and heat stroke, but uses 
laboratory tests, especially liver function tests, to determine when 
sailors are allowed to return to duty. For those who have suffered heat 
stroke, full return to duty is usually not granted until somewhere 
between two days to three weeks later (O'Connor et al., 2007).
    In 2023, the American College of Sports Medicine (ACSM) published 
their consensus statement which provides evidence-based strategies to 
reduce and eliminate HRIs, including a return to activity protocol for 
athletes recovering from EHS (Roberts et al., 2023). Of note, ACSM 
names athletes (whether elite, recreational, or tactical) and 
occupational laborers as groups who are active and regularly perform 
exertional activities that could lead to EHS. Specifically, ACSM 
recommendations include refraining from exercise for at least seven 
days following release from the initial medical care for EHS treatment. 
Once all laboratory results and vital signs have normalized, ACSM 
recommends an individual can exercise in cool environments and 
gradually increase duration, intensity, and heat exposure over a two to 
four-week period to initiate environmental acclimatization (Roberts et 
al., 2023). If the affected athlete does not return to pre-EHS activity 
levels within four to six weeks, further medical evaluation is needed. 
ACSM recommends a full return to

[[Page 70714]]

activity between two to four weeks after the individual has 
demonstrated exercise acclimatization and heat tolerance with no 
abnormal symptoms or test results during the re-acclimatization period 
(Roberts et al., 2023). Similarly, the National Athletic Trainer's 
Association proposes that individuals who experience EHS should 
complete a 7 to 21-day rest period, be asymptomatic, have normal blood-
work values, and obtain a physician's clearance prior to beginning a 
gradual return to activity (Casa et al., 2015).
    In the military setting it is accepted that returning to work too 
early and/or without adequate work restrictions can result in 
incomplete recovery from heat stroke, which may necessitate a prolonged 
restricted work status (McDermott et al., 2007). About 10-20% of people 
who have had heat stroke have been shown to experience heat intolerance 
roughly two months after having the heat stroke (Binkley et al., 2002). 
In some instances, this has lasted for five years and has increased the 
risk for another heat stroke (Binkley et al., 2002; McDermott et al., 
2007). Similarly, a case study report of EHS cases amongst the U.S. 
Army found that in one of the ten cases examined, the person was heat 
intolerant for 11.5 months post-EHS (Armstrong et al., 1989).
    Only a limited number of studies have focused on the long-term 
effects of heat stroke. This includes research by Wallace et al. 
(2007), whose retrospective review of military service members found 
that those who suffered an EHS event earlier in life were more likely 
to die due to cardiovascular disease and ischemic heart disease. 
Similarly, Wang et al. (2019) report that prior exertional heat illness 
was associated with a higher prevalence of acute ischemic stroke, acute 
myocardial infarction, and an almost three-fold higher prevalence of 
chronic kidney disease. Other research in mice support these claims and 
indicate that epigenetic effects post-EHS result in immunosuppression 
and an altered heat shock protein response as well as development of 
metabolic disorders that could negatively impact long-term 
cardiovascular health (Murray et al., 2020; Laitano et al., 2020).
V. Summary
    OSHA's review of the scientific and medical literature indicates 
that occupational heat exposure can cause heat stroke, a medical 
emergency. The physiological mechanisms by which heat exposure can 
result in heat stroke are well-established in the literature, and heat 
exposure as a cause of heat stroke is well-recognized in the medical 
and scientific communities. The best available research demonstrates 
that heat stroke must be treated as soon as possible and that prolonged 
time between experiencing heat stroke and seeking treatment increases 
the likelihood of death and may result in long-term health effects.

F. Heat Exhaustion

I. Introduction
    NIOSH defines heat exhaustion as ``[a] heat-related illness 
characterized by elevation of core body temperature above 38 [deg]C 
(100.4 [deg]F) and abnormal performance of one or more organ systems, 
without injury to the central nervous system'' (NIOSH, 2016). Heat 
exhaustion can progress to heat stroke if not treated properly and 
promptly, and may require time away from work for a full recovery.
    Signs and symptoms of heat exhaustion typically include profuse 
sweating, changes in mental status, dizziness, nausea, headache, 
irritability, weakness, decreased urine output and elevated core body 
temperature up to 40 [deg]C (104 [deg]F) (NIOSH, 2016; Kenny et al., 
2018). Collapse may or may not occur. Significant injury to the central 
nervous system, and significant inflammatory response do not occur 
during heat exhaustion. However, there appears to be a fine line 
between heat exhaustion and heat stroke. Kenny et al. 2018 state that 
it can be difficult to clinically differentiate between heat exhaustion 
and early heat stroke. NIOSH also states that heat exhaustion ``may 
signal impending heat stroke'' (NIOSH, 2016). Armstrong et al. (2007) 
recommend that rectal temperature be taken to distinguish between heat 
exhaustion and heat stroke.
II. Physiological Mechanisms
    Heat exhaustion occurs when heat stress results in elevated body 
temperature between 98.6 [deg]F and 104 [deg]F (37 [deg]C and 40 
[deg]C) and physiological changes occur (Kenny et al., 2018). Under 
these significant heat stress conditions, heavy sweating occurs, tissue 
perfusion is reduced, and inflammatory mediators are released. 
Electrolyte imbalances can occur due to fluid and electrolyte losses 
through sweating paired with inadequate replenishment. Voluntary and 
involuntary dehydration can exacerbate this process (Hendrie et al., 
1997; Brake and Bates, 2003). ``Voluntary dehydration,'' as used by 
Brake and Bates, refers to the circumstance where a dehydrated worker 
does not adequately rehydrate, despite the availability of water. Upon 
review of several studies, Kenny et al. (2018) report that dehydration 
among workers is common, even when water is readily available. There is 
also evidence that even when water intake increases, as sweat rate and 
dehydration increase, intake may not be adequate to fully replace 
losses (Hendrie et al., 1997).
    Brake and Bates (2003) summarized various hypothesized reasons for 
voluntary and involuntary dehydration. One hypothesized reason for 
voluntary dehydration is a delayed or decreased thirst response (Brake 
and Bates, 2003). Other reasons include mechanisms that affect fluid 
retention, such as the dependence of fluid retention on solutes such as 
sodium, which may be in imbalance under heat stress (Brake and Bates, 
2003). Lack of adequate hydration could also be due to workplace 
pressures or concerns about sanitation (Rao, 2007; Iglesias-Rios, 
2023).
    The combination of heat stress, upright posture, and low vascular 
fluid volume (hypovolemia) can further dysregulate the circulatory 
system and affect clotting mechanisms (Kenny et al., 2018). Heat stress 
reduces blood flow to the abdominal organs, kidneys, muscles, and brain 
and increases blood flow to the skin to aid in cooling. These changes 
in the circulatory system and blood flow to the brain can potentially 
lead to dizziness or faintness upon standing (orthostatic intolerance), 
or collapse. Other factors that affect the development of heat 
exhaustion include individual health status, preparedness (such as 
acclimatization level), individual characteristics, knowledge, access 
to fluids, environmental factors, personal protective equipment use and 
work pacing and intensity (Kenny, 2018).
III. Occupational Heat Exhaustion
    Heat exhaustion is one of the more common heat-related illnesses 
(Armstrong et al., 2007; Harduar Morano and Watkins, 2017; Lewandowski 
and Shaman, 2022). In their study of heat-illness hospitalizations in 
Florida during May to October from 2005-2012, Harduar Morano and 
Watkins (2017) reported that there were 2,659 cases of work-related 
heat exhaustion that resulted in emergency department visits or 
hospitalization, versus 181 cases of work-related heat stroke that 
resulted in emergency department visits, hospitalization, or death. 
Similar results have been reported in studies of heat-related illness 
among the United States Armed Forces and miners showing the frequency 
of heat exhaustion (Dickinson, 1994; Armed Forces Health Surveillance 
Division, 2022b;

[[Page 70715]]

Lewandowski and Shaman, 2022; Donoghue et al., 2000; Donoghue, 2004). 
While in some studies heat exhaustion is not specifically diagnosed, 
several qualitative studies describe self-reported symptoms in workers 
that may be indicative of heat exhaustion (e.g., Mirabelli et al., 
2010; Fleischer et al., 2013; Kearney et al., 2016; Mutic et al., 
2018). These symptoms included headache, nausea, vomiting, feeling 
faint, and heavy sweating.
IV. Treatment and Recovery
    Heat exhaustion may require treatment beyond basic first aid to 
prevent progression to heat stroke (Kenny et al., 2018). In cases where 
the degree of severity of heat illness is unclear, the individual 
should be treated as if they have heat stroke (Armstrong, 1989). For a 
worker experiencing heat exhaustion, NIOSH recommends the following 
steps to ensure the worker receives proper and adequate treatment: 
``Take worker to a clinic or emergency room for medical evaluation and 
treatment; If medical care is unavailable, call 911; Someone should 
stay with worker until help arrives; Remove worker from hot area and 
give liquids to drink; Remove unnecessary clothing, including shoes and 
socks; Cool the worker with cold compresses or have the worker wash 
head, face, and neck with cold water; Encourage frequent sips of cool 
water'' (NIOSH, 2016).
    Complete recovery from heat exhaustion may require a restricted 
work status (or limited work duties). Donoghue et al. (2000) reported 
that following heat exhaustion, 29% (22 of 77) of miners included in 
the study required a restricted work status for at least one shift. The 
military has specific protocols for return to duty following heat 
exhaustion. For example, the U.S. Army and Air Force follow the 
protocol outlines in AR 40-501 (O'Connor et al., 2007). Three instances 
of heat exhaustion in less than 24 months can result in referral to a 
Medical Evaluation Board before a full return to service. Some military 
units have additional or more specific guidelines. For example, one 
military unit, at Womack Army Medical Center in North Carolina, has 
guidelines that allow individuals who are considered to have mild 
illness, fully recovered in the emergency room, and have no abnormal 
laboratory findings to return to light duty the following day and 
limited duty the day after that. However, they also indicate that some 
effects of heat illness may be subtle or delayed and recommend 
individuals avoid strenuous exercise for several days and remain under 
observation (O'Connor et al., 2007).
V. Summary
    The scientific and medical literature presented here clearly 
demonstrate that heat exhaustion is a recognized health effect of 
occupational heat exposure. The best available evidence on the 
symptoms, treatment, and recovery of heat exhaustion demonstrates that 
heat exhaustion can progress to heat stroke, a medical emergency, if 
not treated promptly and that heat exhaustion may require time away 
from work for a full recovery.

G. Heat Syncope

I. Introduction
    Occupational heat exposure can result in heat syncope. Syncope is 
the medical term for ``fainting,'' and heat syncope is defined as 
``fainting, dizziness, or light-headedness after standing or suddenly 
rising from a sitting/lying position'' due to heat exposure (NIOSH, 
2023a). Heat syncope may sometimes be referred to as ``exercise-
associated collapse'' (EAC), but heat syncope can happen without 
significant levels of exertion (Asplund et al., 2011; Pearson et al., 
2014). As explained below, heat syncope is an acknowledged and 
documented health effect of occupational heat exposure.
II. Physiological Mechanisms
    There are two mechanisms for how heat exposure can cause heat 
syncope (Schlader et al., 2016; Jimenez et al., 1999). One mechanism 
for heat syncope is reduced blood flow to the brain. Elevated core 
temperature induces vasodilation, sweating, and may result in blood 
pooling in certain areas of the body (see Section IV.B., General 
Mechanisms of Heat-Related Health Effects). Thus, there is a lower 
circulating blood volume, which can reduce blood flow to the brain and 
cause loss of consciousness (Wilson et al., 2006; Van Lieshout et al., 
2003).
    A second mechanism for heat syncope is reduced cerebral blood 
velocity (CBV) (indicative of reduced blood flow to the brain) that 
results in orthostatic intolerance (the inability to remain upright 
without symptoms) during a heat stress episode (Wilson et al., 2006). 
As individuals experience whole body heating, CBV is reduced and 
cerebral vascular resistance (the ratio of carbon dioxide stimulus to 
cerebral blood flow) increases. These changes ultimately contribute to 
reduced cerebral perfusion and blood flow, as well as orthostatic 
intolerance (Wilson et al., 2006). The orthostatic response to heat 
stress during ``rest'' (i.e., standing/sitting) is essentially 
equivalent to the orthostatic response to heat stress after exercise if 
skin temperature is similarly elevated (Pearson et al., 2014). While 
core temperature is not always elevated in cases of heat syncope, skin 
temperature typically is (Department of the Army, 2022; Noakes et al., 
2008).
    Differentiating between heat syncope, heat exhaustion, and heat 
stroke is a critical step in proper diagnosis (Santelli et al., 2014; 
Coris et al., 2004). As stated above, heat syncope always involves loss 
of consciousness, but it does not require elevated core body 
temperature (Santelli et al., 2014; Holtzhausen et al., 1994). 
Conversely, heat exhaustion and stroke do not require loss of 
consciousness. Though central nervous system (CNS) disturbances are 
possible in heat stroke and heat stroke is always characterized by 
significantly elevated core temperature. Further, recovery of mental 
status is faster in heat syncope than in exhaustion and heat stroke, 
since cooling may not be required for treatment of heat syncope (Howe 
and Boden, 2007).
III. Occupational Heat Syncope
    Workers have experienced heat syncope when exposed to heat. A 
survey-based study in southern Georgia found that 4% of 405 farmworkers 
experienced fainting within the previous week (Fleischer et al., 2013). 
Another survey-based study in North Carolina asked 281 farmworkers if 
they had ever experienced heat-related illness and found that 3% of 
workers had fainted (Mirabelli et al., 2010). While these cases were 
not formally diagnosed as heat syncope, Fleischer reported temperatures 
ranging from 34-40 [deg]C (94-104 [deg]F) and a heat index of 37-42 
[deg]C (100-108 [deg]F) at the time workers fainted, and Mirabelli 
described the working conditions at the time of fainting as being in 
``extreme heat.''
IV. Treatment and Recovery
    NIOSH recommends treating heat syncope by having the worker sit 
down in a cool environment and hydrate with either water, juice, or a 
sports drink (NIOSH, 2016). The Department of the Army recommends that 
``victims of heat/parade syncope will recover rapidly once they sit or 
lay supine, though complete recovery of stable blood pressure and heart 
rate (resolution of orthostasis or ability to stand without fainting) 
in some individuals may take 1 to 2 hours'' (Department of the Army, 
2022). Treatment recommendations for athletes consist of moving the 
athlete to a cool area and laying them supine with elevated legs to 
assist in venous return,

[[Page 70716]]

possibly with oral or intravenous rehydration (Peterkin et al., 2016; 
Howe and Boden, 2007; Seto et al., 2005; Lugo-Amador et al., 2004).
    An episode of heat syncope may require time away from work for a 
thorough evaluation to ascertain one's risk for recurrent/future 
episodes of heat syncope. No studies have evaluated recurring episodes 
of syncope among workers specifically, but a study found that, for the 
general population, 1-year syncope recurrence (any type) was 14% in 
working-age people (18-65 years) (Barbic et al., 2019). The U.S. Army 
has a requirement to ``obtain a complete history to rule out other 
causes of syncope, including an exertional heat illness or other 
medical diagnosis (for example, cardiac disorder)'' (Department of the 
Army, 2022). Recommendations for athletes include thorough evaluation 
``for injury resulting from a fall, and all cardiac, neurologic, or 
other potentially serious causes for syncope'' (Howe and Boden, 2007; 
Lugo-Amador et al., 2004; Binkley et al., 2002). Indeed, if an injury 
(e.g., fall, collision) is sustained because of heat syncope, treatment 
beyond first aid (including hospitalization) may be necessary. 
Supporting this point, more general syncope has been linked to 
occupational accidents requiring hospitalizations (Nume et al., 2017).
V. Summary
    The scientific and medical literature presented in this section 
demonstrate that heat syncope is a recognized health effect of 
occupational heat exposure. Studies suggest that heat syncope may 
require time away from work for further evaluation. Additionally, heat 
syncope can lead to injuries (e.g., injury from a fall), some of which 
may require hospitalization.

H. Rhabdomyolysis

I. Introduction
    Rhabdomyolysis is a life-threatening illness that can affect 
workers exposed to occupational heat. NIOSH defines rhabdomyolysis as 
``a medical condition associated with heat stress and prolonged 
physical exertion, resulting in the rapid breakdown of muscle and the 
rupture and necrosis of the affected muscles'' (NIOSH, 2016). This 
definition is specific to exertional rhabdomyolysis. Another form of 
rhabdomyolysis, called traumatic rhabdomyolysis, is caused by direct 
muscle trauma (e.g., from a fall or crush injury). Workers can 
experience such injuries, and consequently suffer from traumatic 
rhabdomyolysis, because of occupational heat exposure (see Section 
IV.P., Heat-Related Injuries). However, this section will focus only on 
exertional rhabdomyolysis. Unless otherwise specified, all references 
to rhabdomyolysis are shorthand for exertional rhabdomyolysis.
    Signs and symptoms of rhabdomyolysis include myalgia (muscle pain), 
muscle weakness, muscle tenderness, muscle swelling, and/or dark-
colored urine (Armed Forces Health Surveillance Division, 2023b; Dantas 
et al., 2022; O'Connor et al., 2008; Cervellin et al., 2010). Notably, 
the onset of these symptoms may be delayed by 24-72 hours (Kim et al., 
2016). Rhabdomyolysis commonly affects individuals who are exposed to 
heat during physical exertion. For example, the Centers for Disease 
Control and Prevention (CDC) investigated an incident in which an 
entire cohort of 50 police trainees were diagnosed with rhabdomyolysis 
after the first 3 days of a 14-week training program; the trainees had 
engaged in heavy physical exertion outdoors with limited access to 
water. The CDC concluded that adequate hydration is particularly 
important when the HI approaches 80 [deg]F (Goodman et al., 1990).
    Rhabdomyolysis has long been recognized as a heat-related illness 
by NIOSH, the U.S. Armed Forces, and national athletic organizations 
such as the American College of Sports Medicine (Armstrong et al., 
2007). Specifically, NIOSH lists rhabdomyolysis as an ``acute heat 
disorder'' in its Criteria for a Recommended Standard (2016) and 
provides detailed recommendations for recognition and treatment of 
rhabdomyolysis. NIOSH also conducted case studies and retrospective 
analyses to identify cases of rhabdomyolysis among workers exposed to 
heat, including firefighter cadets and instructors, as well as park 
rangers (Eisenberg et al., 2019; Eisenberg J et al., 2015; Eisenberg 
and Methner, 2014).
    Similarly, the U.S. Armed Forces developed a case definition that 
specifies rhabdomyolysis can be heat-related (Armed Forces Health 
Surveillance Board, 2017), and this definition is applied in their 
annual surveillance reports of HRIs. From 2018 to 2022, most 
rhabdomyolysis cases (75.9%) occurred during warmer months (i.e., May 
to October) (Armed Forces Health Surveillance Division, 2023b). In a 
retrospective study of hospital admissions for rhabdomyolysis in 
military members (2010-2013), 60.1% (193 out of 321) cases were deemed 
to be associated with exertion and exposure to heat (Oh et al., 2022).
    Many studies have also found that rhabdomyolysis often coincides 
with exertional heat stroke and other HRIs such as heat exhaustion, 
heat cramps, hyponatremia, and dehydration. The frequent co-occurrence 
of rhabdomyolysis and other HRIs has been reported among workers, 
including police and firefighters (Eisenberg et al., 2019; Goodman et 
al., 1990), workers included in OSHA enforcement investigations (Tustin 
et al., 2018a), military members (Oh et al., 2022; Carter et al., 
2005), athletes (Thompson et al., 2018), and in the general population 
(Thongprayoon et al., 2020).
II. Physiological Mechanisms
    Studies have identified two interrelated mechanisms through which 
heat exposure, combined with exertion, can cause rhabdomyolysis. Both 
mechanisms share a common origin: occupational heat exposure and 
exertion both contribute to excessive heat stress, which in turn causes 
an elevated core temperature. Both mechanisms also share a common 
outcome: the breakdown and death of muscle tissue, which is the 
hallmark characteristic of rhabdomyolysis. The first mechanism is 
thermal injury to muscle cells. When the body's core temperature is 
elevated, it creates a toxic environment that can directly injure or 
kill muscle cells. The temperature at which this occurs, known as the 
thermal maximum, is estimated to be about 107.6 [deg]F (42 [deg]C) 
(Bynum et al., 1978). At the thermal maximum, the structural components 
of the cells' membranes are liquified and the membrane breaks down. 
Proteins in the cells' mitochondria, which are key to energy 
production, change shape and no longer function properly. Calcium, 
which is normally maintained at a low level inside muscle cells, will 
rush into the cells and activate inflammatory processes that accelerate 
the death of those cells (Torres et al., 2015; Khan, 2009).
    The second mechanism is lack of oxygen to muscle cells. When the 
body attempts to cool itself, it can lose high volumes of sweat. Sweat 
loss can deplete the body's stores of water and electrolytes, leading 
to low blood volume (see Section IV.B., General Mechanisms of Heat-
Related Health Effects). Low blood volume, and low potassium in the 
blood (known as hypokalemia), can both contribute to muscle cell death. 
An adequate supply of blood is necessary to deliver oxygen to muscles, 
and an adequate supply of potassium is needed to support vasodilation 
(to support increased blood flow to the muscles during exertion). When 
neither blood volume nor

[[Page 70717]]

potassium are sufficient, the muscle cells do not receive enough oxygen 
(known as ischemia). When this occurs, the muscle cells produce less 
energy and eventually will die if exertion continues (Knochel and 
Schlein, 1972).
III. Occupational Rhabdomyolysis
    While OSHA is not aware of surveillance data on the incidence of 
rhabdomyolysis in the worker population in the United States, there are 
surveillance data on the incidence of rhabdomyolysis among active 
military members in the Army, Navy, Air Force, and Marine Corps. These 
data have been reported for the U.S. Army from 2004 to 2006 (Hill et 
al., 2012) and for all military branches from 2008 through 2022 (Armed 
Forces Health Surveillance Division, 2023b; Armed Forces Health 
Surveillance Division, 2018; U.S. Armed Forces, 2013). These 
surveillance data and the studies described above by NIOSH and others 
indicate that workers performing strenuous tasks in the heat are at 
risk of developing rhabdomyolysis. The U.S. Armed Forces has 
successfully identified many cases of heat-related rhabdomyolysis by 
searching medical records for the presence of either the ICD-10 code 
for rhabdomyolysis and/or the ICD-10 code for myoglobinuria, along with 
any other heat-related codes (table IV-1) (Armed Forces Health 
Surveillance Division, 2023b; Oh et al., 2022).
IV. Treatment and Recovery
    Rhabdomyolysis is a serious heat-related illness that can cause 
life-threatening complications. Many cases of rhabdomyolysis may 
require hospitalization. For example, A CDC investigation into a police 
training program in Massachusetts found that 26% of police trainees (13 
out of 50) were hospitalized for rhabdomyolysis only three days into 
their training (Goodman et al., 1990). The mean length of 
hospitalization was 6 days, with a range of 1 to 20 days (Goodman et 
al., 1990). Similarly, a military surveillance study identified 473 
rhabdomyolysis cases among military members in 2022, with 35.3% of 
cases (167 out of 473) requiring hospitalization (Armed Forces Health 
Surveillance Division, 2023b). In a retrospective study of 193 military 
trainees hospitalized for rhabdomyolysis, the mean length of 
hospitalization was 2.6 days, with a range of 0 to 25 days (Oh et al., 
2022).
    The focus of treatment for rhabdomyolysis during hospitalization is 
to reduce levels of creatine kinase (CK) and myoglobin in the blood, as 
well as correct electrolyte imbalances, through aggressive 
administration of intravenous fluids (generally normal saline) 
(O'Connor et al., 2020; Luetmer et al., 2020; Manspeaker et al., 2016; 
Torres et al., 2015). Monitoring is used to repeatedly measure CK 
levels until a peak concentration is reached (often within 1-3 days), 
and then to ensure that CK levels are consistently trending downwards 
before discharge from the hospital (Kodadek et al., 2022; Oh et al., 
2022).
    Complications of rhabdomyolysis are also possible. When muscle 
cells die, they release several electrolytes and proteins into the 
bloodstream that can cause severe health complications. For example, 
the release of potassium from muscle cells can cause hyperkalemia (high 
level of potassium in the blood), which then leads to heart arrhythmias 
(abnormal heart rhythms) (Mora et al., 2017; Sauret et al., 2002). 
Also, the release of myoglobin into the bloodstream can be toxic for 
the kidneys. When blood is filtered by nephrons (functional units of 
the kidneys) to produce urine, the presence of even small amounts of 
myoglobin can obstruct and damage the nephrons (Mora et al., 2017; 
Sauret et al., 2002). In some cases, these complications from 
rhabdomyolysis can be life-threatening (Wesdock and Donoghue, 2019) and 
in fact fatalities have been reported (Gardner and Kark, 1994; Goodman 
et al., 1990). A more detailed discussion of how rhabdomyolysis can 
cause acute kidney injury or other kidney damage can be found in 
Section IV.M., Kidney Health Effects.
    Guidelines for return to work among workers diagnosed with 
rhabdomyolysis are limited. In the U.S. military, soldiers deemed to be 
at low risk for recurrence of rhabdomyolysis are restricted to light, 
indoor duty and encouraged to rehydrate for at least 72 hours to allow 
for normalization of CK levels. If CK levels do not normalize, they 
must continue indoor, light duty; if CK levels do normalize, they can 
proceed to light, outdoor duty for at least 1 week and must show no 
return of clinical symptoms before they can gradually return to full 
duty. In contrast, soldiers deemed to be at high risk for recurrence of 
rhabdomyolysis must undergo additional diagnostic tests, with 
consultation from experts, and can be given an individualized, 
restricted exercise program while they await clearance for full return 
to duty (O'Connor et al., 2020; O'Connor et al., 2008). These 
guidelines have been adopted by the Armed Forces and restated in their 
surveillance reports of rhabdomyolysis (Armed Forces Health 
Surveillance Division, 2023b).
V. Summary
    The available scientific literature indicates that rhabdomyolysis 
can result from physical exertion in the heat. Based on plausible 
mechanistic data, studies by NIOSH and others, and surveillance data 
indicating incidence of rhabdomyolysis among active military members, 
OSHA preliminarily determines that workers performing strenuous tasks 
in the heat are at risk of rhabdomyolysis.

I. Hyponatremia

I. Introduction
    Workers in hot environments may experience hyponatremia, a 
condition that occurs when the level of sodium in the blood falls below 
normal levels (<135 milliequivalents per liter (mEq/L)) (NIOSH, 2016). 
Hyponatremia is often caused by drinking too much water or hypotonic 
fluids, such as sports drinks, over a prolonged period of time. Without 
sodium replacement, the high water intake can result in losses of 
sodium in the blood as more sodium is lost due to increased sweating 
from heat exposure and urination (Korey Stringer Institute (KSI), 
n.d.). Mild forms of hyponatremia may not produce any signs or 
symptoms, or may present with symptoms including muscle weakness and/or 
twitching, dizziness, lightheadedness, headache, nausea and/or 
vomiting, weight gain, and swelling of the hands or feet (KSI, n.d.; 
NIOSH, 2016). In severe cases, hyponatremia may cause altered mental 
status, seizures, cerebral edema, pulmonary edema, and coma, which may 
be fatal (KSI, n.d.; NIOSH, 2016; Rosner and Kirven, 2007). NIOSH and 
the U.S. Army classify hyponatremia as a heat-related illness (NIOSH, 
2016; Department of the Army, 2022).
II. Physiological Mechanisms
    When exposed to heat, the autonomic nervous system triggers the 
body's sweat response, in which sweat glands release water to wet the 
skin (Roddie et al., 1957; Grant and Holling, 1938). The purpose of the 
sweat response is to cool the body. However, in doing so, it can 
deplete the body's stores of water and electrolytes (e.g., sodium, 
potassium, chloride, calcium, and magnesium) that are essential for 
normal bodily function (Shirreffs and Maughan, 1997). As the body's 
store of sodium is lessening and high quantities of water are consumed, 
hyponatremia may develop as sodium in the blood becomes diluted (<135 
mEq/L). In some cases, this dilution may cause an osmotic 
disequilibrium--an imbalance in the amount of sodium inside and outside 
the cell resulting in

[[Page 70718]]

cellular swelling--which can lead to the serious and fatal health 
outcomes discussed above.
III. Occupational Hyponatremia
    Surveillance of hyponatremia among workers is limited. However, a 
recent case study demonstrates the potential severity and life-
threatening nature of hyponatremia. After a seven-day planned absence 
from work, a 34-year-old male process control operator in an aluminum 
smelter pot room was hospitalized due to a variety of HRI symptoms 
including hyponatremia, with serum (the liquid portion of blood 
collected without clotting factors) sodium level of 114 millimoles per 
liter (mmol/L) (reference range: 136-145 mmol/L) (Wesdock and Donoghue, 
2019). After 13 days in the hospital, the patient was discharged with a 
diagnosis of ``severe hyponatremia likely triggered by heat exposure'' 
(Wesdock and Donoghue, 2019). The patient was still out of work 32 
weeks after the incident. While no temperature data for the pot room 
were available, an exposure assessment used outdoor temperatures that 
day and pot room temperatures from the literature to estimate that the 
WBGT could have been as high as 33 [deg]C, which the authors state 
exceeds the ACGIH TLV for light work for acclimatized workers (Wesdock 
and Donoghue, 2019).
    The relationship of heat exposure and hyponatremia was examined 
among male dockyard workers in Dubai, United Arab Emirates (Holmes et 
al., 2011). This population performed long periods of manual work in 
the heat and consumed a diet low in sodium. A first round of plasma 
(i.e., the liquid part of blood collected that contains water, 
nutrients and clotting factors) samples were taken at the end of the 
summer (n=44), with a second round taken at the end of the winter among 
volunteers still willing to participate (n=38). In the summer, 55% of 
participants were found to be hyponatremic (<135 millimolar (mM)), 
whereas only 8% were hyponatremic in the winter. Although ambient 
temperature conditions were not reported, the authors indicate that 
hyponatremia was highest during the summer because of sodium losses 
through sweat and inadequate sodium replacement (Holmes et al., 2011).
    Hyponatremia among the military population has been well documented 
by the Annual Armed Forces Health Surveillance Division, which releases 
annual reports on exertional hyponatremia among active duty component 
services members, each with surveillance data for the previous 15 years 
(e.g., Armed Forces Health Surveillance Division, 2023a; Armed Forces 
Health Surveillance Division, 2022a; Armed Forces Health Surveillance 
Division, 2021; Armed Forces Health Surveillance Division, 2020). Cases 
come from the Defense Medical Surveillance System and include both 
ambulatory medical visits and hospitalizations in both military and 
civilian facilities. During the period of 2004 through 2022, the number 
of cases of hyponatremia among U.S. Armed Forces peaked in 2010 with 
180 cases. The lowest number during that time period was 2013, when 72 
cases were reported. During the last 15 years in which data were 
reported (2007-2022), 1,690 cases of hyponatremia occurred. Of these 
1,690 cases, 86.8% (1,467) were diagnosed and treated during an 
ambulatory care visit (Armed Forces Health Surveillance Division, 
2023a). As the diagnostic code for hyponatremia may include cases that 
are not heat-related, these data may be overestimates. However, such 
overestimation is reduced in this study as the authors controlled for 
many other related diagnoses (e.g., kidney diseases, endocrine 
disorders, alcohol/illicit drug abuse), which can cause hyponatremia.
IV. Treatment and Recovery
    Treatment and recovery for hyponatremia can vary depending on 
severity and symptoms. Workers presenting with mild symptoms should 
increase salt intake by consuming salty foods or oral hypertonic saline 
and restrict fluid until symptoms resolve or sodium levels return to 
within normal limits (KSI, n.d.). Medical attention may be required in 
severe cases, which may be life-threating, and may be sought to address 
symptoms and personal risk factors (e.g., history of heart conditions, 
on a low sodium diet) (NIOSH, 2016).
V. Summary
    The available evidence in the scientific literature indicates that 
hyponatremia can result from occupational heat exposure. The evidence 
on treatment and recovery demonstrates that hyponatremia can require 
medical attention and, in some cases, may be life-threatening.

J. Heat Cramps

I. Introduction
    Workers exposed to environmental or radiant heat can experience 
sudden muscle cramps known as ``heat cramps.'' NIOSH defines heat 
cramps as ``a heat-related illness characterized by spastic 
contractions of the voluntary muscles (mainly arms, hands, legs, and 
feet), usually associated with restricted salt intake and profuse 
sweating without significant body dehydration'' (NIOSH, 2016). Someone 
can experience heat cramps even if they are frequently hydrating with 
water, but they are not replenishing electrolytes. Heat cramps are 
recognized as a ``heat-related illness'' by numerous organizations, 
including NIOSH, U.S. Army, U.S. Navy, National Athletic Trainers' 
Association (NATA), American College of Sports Medicine (ACSM), and 
World Medicine (formerly known as IAAF).
II. Physiological Mechanisms
    It is recognized in the medical and scientific communities that 
heat cramps result from heat exposure. However, the exact physiological 
mechanism is not known. In an early study of heat cramps, investigators 
included the following as the diagnostic criteria for heat cramps: 
exposure to high temperatures at work; painful muscle cramps; rapid 
loss of salt in the sweat that is not replaced (which may cause 
hyponatremia); diminished concentration of chloride in the blood and in 
the body tissues (also known as hypochloremia); and rapid amelioration 
of symptoms after appropriate treatment (Talbott and Michelsen, 1933).
    The following mechanism has been proposed for the development of 
heat cramps: profuse sweating can deplete electrolyte stores (e.g., 
sodium (Na), potassium (K), calcium (Ca)), which exacerbates muscle 
fatigue and can cause heat cramps (Bergeron, 2003; Horswill et al., 
2009; Schallig et al., 2017; Derrick, 1934). The U.S. Army further 
posits that ``intracellular calcium is increased via a reduction in the 
sodium concentration gradient across the cell membrane. The increased 
intracellular calcium accumulation then stimulates actin-myosin 
interactions (that is, filaments propelling muscle filaments) causing 
the muscle contractions'' (Department of the Army, 2022). Heat cramps 
are sometimes referred to, more broadly, as exercise-associated muscle 
cramps (EAMCs) (Bergeron et al., 2008). However, heat cramps are 
distinct in that they only occur in hot conditions, which exacerbate 
electrolyte depletion, and may or may not be associated with exercise.
III. Occupational Heat Cramps
    Surveillance data and survey study data demonstrate that workers 
exposed to environmental or radiant heat frequently experience heat 
cramps in the United States. In a study of heat-related illness 
hospitalizations and deaths for the U.S. Army from 1980-

[[Page 70719]]

2002, 8% of heat-related illness hospitalizations recorded were due to 
heat cramps (Carter et al., 2005). Similarly, in studies of self-
reported heat-related illness, workers frequently cite heat cramps as a 
common symptom of heat exposure. Specifically, in several studies of 
self-reported heat-related symptoms among farmworkers in multiple 
States, participants reported experiencing sudden muscle cramps in the 
prior week in Georgia (33.7% of 405 respondents) (Fleischer et al., 
2013), North Carolina (35.7% of 158 respondents) (Kearney et al., 
2016), and Florida (30% of 198 respondents) (Mutic et al., 2018). In 
another study of self-reported symptoms among 60 migrant farmworkers in 
Georgia, heat-related muscle cramps were reported by 25% of 
participants, the second most frequently reported HRI symptom (Smith et 
al., 2021). In a study examining exertional heat illness and 
corresponding wet bulb globe temperatures in football players at five 
southeastern U.S. colleges from August to October 2003, the authors 
found that the highest incidences of exertional heat illness (EHI) 
occurred in August (88%, EHI rate= 8.95/1000 athlete-exposures (Aes)) 
and consisted of 70% heat cramps (6.13/1000 Aes) (Cooper et al., 2016).
IV. Treatment and Recovery
    Treatment for heat cramps includes electrolyte-containing fluid 
replacement (also known as isotonic fluid replacement), stretching, and 
massage (Gauer and Meyers, 2019; Peterkin et al., 2016). In some cases, 
sodium replacement may be a treatment for heat cramps (Talbott and 
Michelsen, 1933; Sandor, 1997; Jansen et al., 2002). In severe cases, 
it is recommended that magnesium levels of the patient are obtained and 
if necessary, magnesium replacement through IV therapy is provided 
(O'Brien et al., 2012). The ACSM recommends rest, prolonged stretching 
in targeted muscle groups, oral sodium chloride ingestion in fluids or 
foods, or intravenous normal saline fluids in severe cases (ACSM, 
2007). NIOSH recommends that medical attention is needed if the worker 
has heart problems, is on a low sodium diet, or if cramps do not 
subside within 1 hour (NIOSH, 2016). If treated early and effectively, 
individuals may return to activity after heat cramps have subsided 
(Bergeron, 2007; Savioli et al., 2022; Gauer and Meyers, 2019). 
However, severe heat cramps may require an emergency department visit 
or hospitalization (Harduar Morano and Waller, 2017; Carter et al., 
2005). While most cases of heat cramps do not require restricted work 
status or time away from work, guidelines for military personnel 
suggest some cases may require light workload the next day and limited 
workload the following day, with observation of the affected patient 
because some additional deficits may be delayed or subtle (O'Connor et 
al., 2007). In addition, guidelines for military personnel advise that 
strenuous exercise be avoided for several days in some cases of heat 
cramps (O'Connor et al., 2007). Severe heat cramps may also elicit 
soreness for several days which can lead to a longer recovery period 
(Casa et al., 2015).
V. Summary
    OSHA's review of the scientific and medical literature indicates 
that heat cramps are a recognized health effect of occupational heat 
exposure. Indeed, several studies of self-reported symptoms of HRI 
among farmworkers in multiple States have indicated that heat cramps 
are quite common. The best available evidence on treatment and recovery 
indicates that heat cramps can, in some cases, require medical 
attention and may require time away from work or an adjusted workload.

K. Heat Rash

I. Introduction
    Workers in hot environments may experience heat rash. Heat rash is 
defined by NIOSH as ``a skin irritation caused by excessive sweating 
during hot, humid weather'' (NIOSH, 2022). NIOSH, the U.S. Army, and 
the U.S. Navy classify heat rash as a heat-related illness (NIOSH, 
2016; Department of the Army, 2022; Department of the Navy, 2023). Also 
known as miliaria rubra or prickly heat, workers with heat rash develop 
red clusters of pimples or small blisters, which can produce itchy or 
prickly sensations that become more irritating as sweating persists in 
the affected area. Heat rash can last for several days and tends to 
form in areas where clothing is restrictive and rubs against the skin, 
most commonly on the neck, upper chest, groin, under the breasts, and 
in elbow creases (OSHA, 2011; NIOSH, 2022; OSHA, 2024a). If left 
untreated, heat rash can become infected, and more severe cases can 
lead to high fevers and heat exhaustion (Wenzel and Horn, 1998). In 
some cases, heat rash can lead to hypohidrosis (i.e., the reduced 
ability to sweat) in the affected area, even weeks after the heat rash 
is no longer visible, which impairs thermoregulation and can cause 
predisposition for heat stress (Sulzberger and Griffin, 1969; Pandolf 
et al., 1980; DiBeneditto and Worobec, 1985). This can impair an 
employee's ability to work and prevent resumption of normal work 
activities in hot environments to allow for the area to heal, which in 
some cases can take 3-4 weeks for heat intolerance to subside (Pandolf 
et al., 1980).
II. Physiological Mechanisms
    The development of heat rash has been studied for centuries 
(Renbourn, 1958). While working in hot environments with a high 
relative humidity, the body's ability to cool itself is greatly 
reduced, as sweat is less likely to evaporate from the skin (Sulzberger 
and Griffin, 1969; DiBeneditto and Worobec, 1985). Heat rash occurs 
when sweat remains on the skin and causes a blockage of sweat (eccrine) 
glands and ducts (Wenzel and Horn, 1998). Since the sweat ducts are 
blocked, sweat secretions can leak and accumulate beneath the skin, 
causing an inflammatory response and resulting in clusters of red bumps 
or pimples (Dibeneditto and Worobec, 1985). If left untreated, heat 
rash may become infected (Holzle and Kligman, 1978). Depending on the 
level of blockage, this can manifest as various types of miliaria, with 
miliaria rubra being the most common form of heat rash (Wenzel and 
Horn, 1998).
III. Occupational Heat Rash
    Surveillance of heat rash in worker populations is limited. 
However, farmworkers have reported cases of skin rash or skin bumps 
while working in summer months (Bethel and Harger, 2014; Kearney et 
al., 2016; Luque et al., 2020). From these studies, the percentage of 
participants surveyed or interviewed that report experiencing skin rash 
or skin bumps in the previous week were 10% (n=100, Beth and Harger, 
2014), 12.1% (n=158, Kearney et al., 2016) and 5% (n=101, Luque et al., 
2020). Although these studies do not purport a diagnosis, presentation 
of skin rash or skin bumps while working in hot environments with 
reported average high temperatures ranging to the mid-90s [deg]F 
indicates respondents may have developed heat rash.
    Similar findings with diagnosis of heat rash or related symptoms 
have been recorded outside of the U.S. among workers in the following 
professions: 17% of indoor electronics store employees in air-
conditioned (4%) and non-air-conditioned (13%) areas in Singapore 
(n=52, Koh, 1995); 2% of underground miners at a site in Australia 
(n=1,252, Donoghue and Sinclair, 2000); 34% of maize farmers in Nigeria 
(n=396, Sadiq et al., 2019); 68% of sugarcane cutters and 23% of

[[Page 70720]]

sugarcane factory workers in Thailand (n=183, Boonruksa et al., 2020); 
41% of sugarcane farmers in Thailand (n=200, Kiatkitroj et al., 2021); 
17% of autorickshaw drivers (n=78), 23% of outdoor street vendors 
(n=75), 16% of street sweepers (n=75) in India (n=228, Barthwal et al., 
2022); and 13% of underground and open pit miners across Australia 
(n=515, Taggart et al., 2024). Although these studies illustrate the 
prevalence of heat rash in various worker populations, OSHA notes that 
differences in study methodologies and the populations studied mean 
that the results of these studies are not necessarily directly 
comparable to each other or to similar industries or worker populations 
in the United States.
    The type of clothing worn may also contribute to formation of heat 
rash while working in higher temperatures. Heat rash was formally 
diagnosed among U.S. military personnel wearing flame resistant army 
combat uniforms in hot and arid environments (102.2 [deg]F to 122 
[deg]F (39 [deg]C to 50 [deg]C), 5% to 25% relative humidity) (Carter 
et al., 2011). In this case series, 18 patients with heat rash 
presented with moderate to severe skin irritation, which was worsened 
by reactions to chemical additives not removed from the laundering 
process and increased heat retention from sweat-soaked clothing, as 
well as the friction from the fabric and the occlusive effect of the 
clothing, which allowed sweat to accumulate on the skin despite the 
lower humidity (Carter et al., 2011). This study calls attention to the 
effect of clothing on the development of heat rash and factors that may 
influence its severity.
IV. Treatment and Recovery
    Although most cases of heat rash can be self-treated without 
seeking medical attention, symptoms typically last for several days 
(Wenzel and Horn, 1998). It is important that heat rash is kept dry and 
cool to avoid possible infection. Workers experiencing heat rash should 
move to a cooler and less humid work environment and avoid tight-
fitting clothing, when possible (NIOSH, 2022). The affected area should 
be kept dry, and ointments and creams, especially if oil-based, should 
not be used (NIOSH, 2022). However, powder may be used for relief.
V. Summary
    The available evidence in the scientific literature indicates that 
heat rash can result from occupational heat exposure. Although heat 
rash usually resolves on its own without medical attention, symptoms 
often persist for several days and more severe cases can impair an 
employee's ability to work and lead to infection if left untreated.

L. Heat Edema

I. Introduction
    Workers in hot environments may experience heat edema. Heat edema 
is the swelling of soft tissues, typically in the lower extremities 
(feet, ankles, and legs) and hands, and may be accompanied by facial 
flushing (Gauer and Meyers, 2019). Surveillance systems and the U.S. 
Army classify heat edema as a heat-related illness (Department of the 
Army, 2022). Workers who are sitting or standing for prolonged periods 
may be at higher risk for heat edema (Barrow and Clark, 1998). Workers 
who are not fully acclimatized to the work site may be more prone to 
developing heat edema as the body adjusts to hotter temperatures (Howe 
and Boden, 2007).
II. Physiological Mechanism
    When exposed to heat, the body increases blood flow and induces 
vasodilation to cool itself and thermoregulate. This means, as blood is 
shunted towards the skin and vasodilation begins, the blood vessels 
near the skin's surface become wider (Hough and Ballantyne, 1899; 
Kamijo et al., 2005). However, blood can pool in areas of the body that 
are most subject to gravity (e.g., legs), and fluid can seep from blood 
vessels causing noticeable swelling under the skin--this is known as 
heat edema (Gauer and Meyers, 2019).
III. Occupational Heat Edema
    Surveillance of heat edema is limited. Many studies include heat 
edema as one of many HRIs that contributed to an aggregate measure of 
HRI in worker, military, or general populations, but very few were 
found to quantify heat edema alone.
    Multiple studies outside of the U.S. have examined HRIs among farm 
and factory workers in the sugarcane industry through surveys and 
interviews (Crowe et al., 2015; Boonruksa et al., 2020; Kiatkitroj et 
al., 2021; Debela et al., 2023). Respondents in the studies were asked 
if they experienced swelling of the feet or hands (with varying degrees 
of frequency) during periods of heat exposure, which could indicate 
presentation of heat edema. In different samples of sugarcane workers 
in two provinces of Thailand, two studies found incidence of swelling 
of the hands and feet. Among sugarcane cutters, 16.7% self-reported 
ever experiencing swelling of the hands or feet and 5.6% self-reported 
experiencing these symptoms (mean 30.6 [deg]C WBGT) (n=90, Boonruksa et 
al., 2020). In another province, 10.5% self-reported swelling of the 
hands/feet while working one summer (n=200, Kiatkitroj et al., 2021).
    While comparing HRI symptoms among sugarcane harvesters and non-
harvesters in Costa Rica, 15.1% of harvesters (n=106) and 7.9% of non-
harvesters (n=63) self-reported having ever experienced swelling of 
hands/feet (p=0.173) (n=169, Crowe et al., 2015). While 7.5% of 
harvesters, who worked outdoors in the field, self-reported 
experiencing this symptom at least once per week, no non-harvesters 
self-reported swelling with this level of frequency (p=0.026) (Crowe et 
al., 2015). The sample of non-harvesters included both workers that 
were intermediately exposed to heat (e.g., in the processing plant or 
machinery shop) and workers not exposed to heat (e.g., in offices).
    In a sample of sugarcane factory workers (n=1,524) in Ethiopia, 
72.4% (1,104) were considered exposed to heat defined as conditions 
exceeding the ACGIH's TLV (Debela et al., 2023). Of the total sample 
(including workers considered exposed to heat and not), 78% (1,189) 
self-reported having experienced swelling of hands and feet at least 
once per week, which was the most commonly reported HRI symptom (Debela 
et al., 2023). Although these studies do not purport a diagnosis, 
presentation of swelling of the hands and feet while working in hot 
environments suggests respondents may have developed heat edema.
IV. Treatment and Recovery
    Although most cases of heat edema can be self-treated without 
seeking medical attention, symptoms can last for days and reoccurrence 
is less likely if individuals are properly acclimatized (Howe and 
Boden, 2007; Department of the Army, 2023). It is important that the 
affected individual moves out of the heat and elevates the swollen 
area. Diuretics are not typically recommended for treatment (Howe and 
Boden, 2007; Gauer and Meyers, 2019; CDC, 2024a).
V. Summary
    The available evidence in the scientific literature indicates that 
heat edema can result from occupational heat exposure, causing swelling 
of the lower extremities (feet, ankles, and legs) and hands. It may be 
difficult to move swollen body parts, thereby impeding an employee's 
ability to perform their job. The need for medical attention can 
typically be avoided if the condition is properly treated.

[[Page 70721]]

M. Kidney Health Effects

I. Introduction
    The kidneys perform many functions in the body, including filtering 
toxins out of the blood and balancing the body's water and electrolyte 
levels (NIDDK, 2018). Working in the heat places a lot of demand on the 
kidneys to conserve water and regulate electrolytes, like sodium, lost 
through sweat. A growing body of experimental and observational 
literature suggests that intense heat strain can cause damage to the 
kidneys in the form of acute kidney injury (AKI), even independent of 
conditions like heat stroke and rhabdomyolysis. An epidemic of chronic 
kidney disease in Central America and other regions around the world 
has placed additional attention on the potential of recurrent heat 
stress-related AKI to cause chronic kidney disease (CKD) over time 
(Johnson et al., 2019; Schlader et al., 2019). Working in the heat has 
also been associated with the development of kidney stones among 
workers outside the U.S., likely a result of decreased urine volume 
leading to increased concentration of minerals in the urine that 
crystallize into stones.
    Each kidney is comprised of hundreds of thousands of functional 
units called nephrons. Each nephron has multiple parts, including the 
glomerulus (a cluster of blood vessels that conduct the initial 
filtering of large molecules) and the tubules (tubes that reabsorb 
needed water and minerals and secrete waste products). The fluid that 
remains after traveling through the glomeruli and tubules becomes urine 
and is eliminated from the body (NIDDK, 2018).
    This section will discuss three kidney-related health effects 
associated with heat exposure: kidney stones, AKI, and CKD.
II. Kidney Stones
A. Introduction
    Kidney stones are hard objects that form in the kidney from the 
accumulation of minerals. They range in size from a grain of sand to a 
pea (NIDDK, 2017a). Symptoms include sharp pain in the back, side, 
lower abdomen, or groin; pink, red, or brown blood in the urine; a 
constant need to urinate; pain while urinating; inability to urinate or 
only able to urinate a small amount; and cloudy or foul-smelling urine 
(NIDDK, 2017b). Nausea, vomiting, fever, and chills are also possible, 
and symptoms may be brief, prolonged, or come in waves (NIDDK, 2017b). 
In rare cases or when medical care is delayed, kidney stones can lead 
to complications including severe pain, urinary tract infections (UTI), 
and loss of kidney function (NIDDK, 2017a). Risk factors for kidney 
stones include being male, a family history of kidney stones, having 
previously had kidney stones, not drinking enough liquids, other 
medical conditions (e.g., chronic inflammation of the bowel, digestive 
problems, hyperparathyroidism, recurrent UTIs), drinking sugary 
beverages, and working in the heat, especially if unacclimatized 
(NIDDK, 2017a; Maline and Goldfarb, 2024). NIOSH has also cautioned 
workers that experiencing chronic dehydration can increase the risk of 
developing kidney stones (NIOSH, 2017a).
B. Physiological Mechanisms
    Kidney stones form when concentrations of minerals are high enough 
to the point of forming crystals, which then aggregate into a stone in 
either the renal tubular or interstitial fluid (Ratkalkar and Kleinman, 
2011). Reduced urine volume, altered urine pH, diet, genetics, or many 
other factors may cause this concentration of minerals (Ratkalker and 
Kleinman, 2011). Heat exposure has the potential to cause kidney stones 
through heat-induced sweating and dehydration. Loss of extracellular 
fluid increases osmolality (i.e., increased concentration of solutes, 
like sodium and glucose) which leads to increased secretion of 
vasopressin, an antidiuretic hormone. Vasopressin signals to the 
kidneys to conserve water by reducing urine volume, leading to 
increased concentration of relatively insoluble salts, like calcium 
oxalate, in the urine. These salts can eventually form crystals which 
can develop into stones (Fakheri and Goldfarb, 2011).
C. Occupational Heat Exposure and Kidney Stones
    Epidemiological studies conducted outside the U.S. have documented 
the association between working in heat and developing kidney stones. 
One of the earliest publications on occupational heat and kidney stones 
was a small study of beach lifeguards in Israel (Better et al., 1980). 
Eleven of 45 randomly selected lifeguards (24%) were found to have had 
kidney stones, which Better et al. noted was approximately 20 times the 
incidence rate of the general Israeli population at the time. The 
authors attributed this finding to low urine output due to dehydration, 
hyperuricemia (elevated levels of uric acid in the blood), and 
absorptive hypercalciuria (elevated levels of calcium in the urine), 
among other factors. In 1992, Pin et al. compared outdoor workers 
exposed to hot environmental conditions to indoor workers exposed to 
cooler conditions (Pin et al., 1992). This study of 406 men in Taiwan 
included quarry, postal, and hospital engineering support workers. The 
prevalence of kidney stones was found to be significantly higher in the 
outdoor workers than the indoor workers (5.2% versus 0.85%, p<0.05). 
The authors posited that chronic dehydration from working outdoors in a 
tropical environment might explain the higher prevalence of kidney 
stones among outdoor workers (Pin et al., 1992).
    Several studies have also considered occupational exposure to 
indoor heat sources. Borghi et al. studied machinists who had been 
working in the blast furnaces of a glass plant in Parma, Italy for five 
or more years, excluding those who had kidney stones before working at 
the plant (Borghi et al., 1993). The prevalence of kidney stones was 
significantly higher among machinists exposed to heat (n=236) than 
among those working in cooler temperatures (n=165) (8.5% vs. 2.4%, 
p=0.03) (Borghi et al., 1993). An analysis of risk factors revealed 
that workers in the heat lost substantially more water to sweat and 
that their urine had higher concentrations of uric acid, higher 
specific gravity, and lower pH than workers in normal temperatures 
(Borghi et al., 1993).
    In a large study in Brazil, the prevalence of at least one episode 
of kidney stones was 8.0% among the 1,289 workers in hot areas, which 
was significantly higher than the 1.75% prevalence found among the 
9,037 people working in room temperature conditions (p<0.001) (Atan et 
al., 2005). An analysis of a subset of workers demonstrated that 
workers in hot temperatures had significantly less citrate in their 
urine (p=0.03) and lower urinary volume (p=0.01) compared to room-
temperature workers.
    Venugopal et al. studied 340 steel workers in southern India 
engaged in moderate to heavy labor with three or more years of heat 
exposure (Venugopal et al., 2020). Of the 340 participants, 91 workers 
without other risk factors for kidney disease, but who had reported a 
symptom of kidney or urethral issues, underwent renal ultrasounds, 
which revealed that 27% had kidney stones. 84% of the participants with 
kidney stones were occupationally exposed to heat, as defined as 
working in conditions above the ACGIH TLV. Having five or more years of 
heat exposure was significantly associated with risk of kidney stones, 
while

[[Page 70722]]

controlling for smoking (OR: 3.6, 95% CI: 1.2, 10.7).
    Most recently, Lu et al. studied 1,681 steel workers in Taiwan, 12% 
of whom had kidney stones, compared to the age-adjusted prevalence 
among men in Taiwan of 9% (Lu et al., 2022). Heat exposure was found to 
be positively associated with prevalence of stones, particularly among 
workers <=35 years old (OR: 2.7, 95% CI: 1.2, 6.0) (Lu et al., 2022).
    Overall, the peer-reviewed literature supports occupational heat 
exposure as a risk factor for kidney stones, in both indoor and outdoor 
environments, across multiple countries, and in several industries.
D. Treatment and Recovery
    Treatment of kidney stones depends on their size, location, and 
type. Someone with a small kidney stone may be able to pass it by 
drinking plenty of water and taking pain medications as prescribed by a 
doctor (NIDDK, 2017c). Larger kidney stones can block the urinary 
tract, cause intense pain, and may require medical intervention such as 
shock wave lithotripsy, cystoscopy, ureteroscopy, or percutaneous 
nephrolithotomy to remove or break up the stone (NIDDK, 2017c). 
Percutaneous nephrolithotomy, whereby kidney stones are removed through 
a surgical incision in the skin, requires several days of 
hospitalization, but the other interventions typically do not require 
an overnight hospital stay (NIDDK, 2017c). One study found that among 
working aged adults, approximately one third of people treated for 
kidney stones miss work and that they miss, on average, 19 hours of 
work per person (Saigal et al., 2005). With monitoring or treatment, 
people typically recover from kidney stones. However, over the long 
term, individuals who develop kidney stones are at increased risk of 
chronic kidney disease and end-stage renal disease, particularly if 
kidney stones are recurrent (Uribarri, 2020).
E. Summary
    The available peer-reviewed scientific literature demonstrates 
occupational heat exposure as a risk factor for kidney stones, in both 
indoor and outdoor environments. Kidney stones may require medical 
treatment and in some cases hospitalization. Finally, individuals who 
develop kidney stones are at increased risk of other kidney diseases.
III. Acute Kidney Injury
A. Introduction
    Acute kidney injury (AKI) can affect workers exposed to 
occupational heat. AKI is an abrupt decline in kidney function in a 
short period (e.g., a few days). As normally functioning kidneys filter 
blood and maintain fluid balance in the body, AKI events can disrupt 
this fluid balance, which can impact major organs like the heart. AKI 
can also have metabolic consequences, like a build-up of too much 
potassium in the blood (hyperkalemia) (Goyal et al., 2023). AKI is not 
always accompanied by symptoms and is typically diagnosed with blood 
and/or urine tests (e.g., increase in serum creatinine). While damage 
to the kidneys is one potential consequence of heat stroke (such as in 
the context of multi-organ failure, as mentioned in Section IV.E., Heat 
Stroke), this section is focused on AKI that is not necessarily 
preceded by clinical heat stroke.
B. Physiological Mechanisms
    There are three categories of AKI used to distinguish the location 
of the cause(s) of AKI--prerenal, intrarenal, and postrenal (Goyal et 
al., 2023). Prerenal AKI represents a reduction in blood volume being 
delivered to the kidneys (i.e., renal hypoperfusion). This can be the 
result of heat-induced sweating that leads to reduced circulating blood 
volume. Prerenal AKI that is reversed (e.g., dehydration is quickly 
reversed) is typically not associated with impairment to the kidney 
glomeruli or tubules, however prolonged exposure can lead to direct 
injury to renal cells through ischemia (inadequate blood and oxygen 
supply to cells). Intrarenal AKI is when the function of the glomeruli, 
tubules, or interstitium are affected, such as in the case of 
nephrotoxic exposures (e.g., heavy metals) or prolonged ischemia. 
Rhabdomyolysis, which was previously discussed in Section IV.H., 
Rhabdomyolysis, is one potential cause of necrosis of tubular cells 
resulting from myoglobin precipitation and direct iron toxicity (Sauret 
et al., 2002, Patel et al., 2009). Postrenal AKI is when there is an 
obstruction to the flow of urine, such as kidney stones, pelvic masses, 
or prostate enlargement. Postrenal AKI is less relevant to a discussion 
of heat-related health effects, apart from kidney stones, which is 
discussed in Section IV.M.II., Kidney Stones.
    Researchers have written specifically about potential mechanisms 
leading from occupational heat exposure to AKI (Roncal-Jim[eacute]nez 
et al., 2015; Johnson et al., 2019; Schlader et al., 2019; Hansson et 
al., 2020), often in the context of chronic kidney disease. As 
previously discussed in Section IV.B., General Mechanisms of Heat-
Related Health Effects, working in the heat can lead to increases in 
core temperature and reductions in circulating blood volume. 
Researchers hypothesize that elevated core temperature could directly 
injure renal tissue or that injury could be mediated through 
subclinical (mild and asymptomatic) rhabdomyolysis or increases in 
intestinal permeability that can cause inflammation. Reductions in 
blood volume could inflame or injure the kidneys through reduced renal 
blood flow that leads to ischemia and/or local reductions in adenosine 
triphosphate (ATP) availability. Reduced blood flow and increased blood 
osmolality also trigger physiologic pathways (e.g., renin-angiotensin-
aldosterone system, polyol-fructokinase pathway) which are energy-
intensive and may lead to oxidative stress and inflammation. Other 
mechanistic pathways under investigation include urate crystal-induced 
injury (Roncal-Jim[eacute]nez et al., 2015) and increased reabsorption 
of nephrotoxicants (Johnson et al., 2019).
C. Identifying Cases of Acute Kidney Injury
    Serum creatinine levels are used in clinical settings to estimate 
kidney function (glomerular filtration rate, or GFR), as it is 
typically produced in the body at a relatively stable rate and is 
removed from circulation by the kidneys. Multiple criteria exist for 
defining AKI based on increases in serum creatinine over hours or days, 
such as the KDIGO criteria published by a non-profit organization that 
produces recommendations on kidney disease (KDIGO, 2012). There are 
multiple factors that could affect the reliability of using serum 
creatinine to estimate GFR, including the increased production of 
creatinine during exercise. As a result of the limitations of serum 
creatinine, there is growing use of alternative biomarkers to identify 
cases of AKI, which may be more reliable and specific to AKI, such as 
neutrophil gelatinase-associated lipocalin, or NGAL.
D. Experimental Evidence
    Researchers have documented an association between heat strain and 
biomarkers of AKI in controlled experimental conditions. In 2013, 
Junglee et al. documented elevations in urine and plasma NGAL and 
reductions in urine flow rate in participants after a heat stress trial 
that induced elevations in core temperature and reductions in body mass 
(an indication of hydration status) (Junglee et al., 2013). These 
increases in NGAL were higher in an experimental group that underwent a 
muscle damaging, downhill (-10% gradient) run (compared to a non-

[[Page 70723]]

muscle damaging run on a 1% gradient) prior to the heat stress trial, 
providing support for the argument that subclinical rhabdomyolysis may 
be a pathway from heat stress to kidney injury. Schlader et al. 
conducted a trial in which participants wearing firefighting gear 
completed two separate exercise trials in hot conditions of different 
durations. The longer duration trial was intended to induce higher 
levels of heat strain, while the shorter duration was intended to 
induce lower levels (Schlader et al., 2017). The researchers found that 
the longer trial was associated with elevated core temperature and 
reduced blood volume, as well as increases in serum creatinine and 
plasma NGAL, suggesting the magnitude of kidney injury may be 
proportional to the magnitude of heat strain. McDermott et al. tested 
longer durations of exercise in the heat (5.7  1.2 hours) 
and similarly found elevations in serum creatinine and serum NGAL from 
before the trial to after (McDermott et al., 2018). To determine 
whether it is elevated core temperature or reduced blood volume that 
primarily drives heat-induced AKI, Chapman et al. conducted four trials 
in which subjects exercised for two hours in the same conditions, but 
received different interventions (water, cooling, water plus cooling, 
and no intervention) (Chapman et al., 2020). The group with no 
intervention had the highest levels of urinary AKI biomarkers in the 
recovery period, whereas the water and cooling groups each experienced 
reductions in AKI biomarker levels relative to the control group. The 
researchers concluded that limiting hyperthermia and/or dehydration 
reduces the risk of AKI.
    The relationship between AKI and hyperthermia and/or dehydration 
has also been demonstrated in animal models (Hope and Tyssebotn 1983; 
Miyamoto 1994; Roncal-Jim[eacute]nez et al., 2014; Sato et al., 2019).
E. Cases of Occupational Heat-Related AKI
    In addition to experimental evidence, heat-related AKI has also 
been observed in ``real world'' conditions going back to the 1960s. In 
1967, Schrier et al. documented evidence of military recruits 
developing AKI (referred to as ``acute renal failure'') following 
training exercises in the heat (Schrier et al., 1967). It was soon 
after reported that AKI cases linked to exercise in the heat 
represented a sizeable portion (approximately 10%) of all AKI cases 
treated at Walter Reed General Hospital in the early 1960s (Schrier et 
al., 1970).
    More recently, serum creatinine-defined AKI has been observed in 
agricultural workers in both Florida and California. Among a cohort of 
field workers from the Central Valley of California, Moyce et al. 
report a post-work shift incidence of AKI of 12.3% (35 of 283 workers) 
(Moyce et al., 2017). Workers with heat strain, characterized by 
increased core temperature and heart rate, were significantly more 
likely to have AKI (OR: 1.34, 95% CI: 1.04, 1.74). Among a cohort of 
agricultural workers in Florida, Mix et al. found that heat index 
(based on nearest weather monitor) was positively associated with the 
risk of AKI--47% increase in the odds of AKI for every 5 [deg]F 
increase in heat index. The authors reported an incidence of AKI of 33% 
(i.e., 33% of workers had AKI on at least one day of monitoring) in 
this study (Mix et al., 2018).
    OSHA researchers have also identified cases of heat-related AKI 
among workers in the agency's own databases: the Severe Injury Reports 
(SIR) database and case files from consultations by the Office of 
Occupational Medicine and Nursing (OOMN) (Shi et al., 2022). Shi et al. 
identified 22 cases of heat-related AKI between 2010 and 2020 in the 
OOMN consultation records (based on serum creatine elevations meeting 
the KDIGO requirements) after excluding cases related to severe 
hyperthermia, multi-organ failure, or death. Using inclusion criteria 
of a heat-related OIICS code (172*) and a mention of AKI in the 
narrative, they also identified 57 cases of probable heat-related AKI 
between 2015 and 2020 in the SIR database.
    Studies conducted among workers outside the U.S. have also reported 
a relationship between working in the heat and acute elevations in 
serum creatinine or increased risk of AKI (Garc[iacute]a-Trabanino et 
al., 2015; Wegman et al., 2018; Nerbass et al., 2019; Sorensen et al., 
2019).
    There are a few limitations to these observational studies, such as 
the use of serum creatinine to characterize AKI, as described above. An 
additional limitation is the inability to determine from these studies 
whether the AKI observed is due to prerenal or intrarenal causes. As 
discussed in Physiological Mechanisms, prerenal AKI may be due to 
reductions in renal blood flow (which would be expected in cases of 
dehydration) and is not necessarily indicative of clinically 
significant structural injury. Another limitation may be the use of 
serum creatinine measures taken over relatively short spans of time, 
which may be too short to see true reductions in GFR (Waikar and 
Bonventre, 2009). However, there are a growing number of studies that 
find a relationship between short-term fluctuations in serum creatinine 
and longer-term declines in kidney function among outdoor workers (see 
discussion in Section IV.M.IV., Chronic Kidney Disease).
F. Treatment and Recovery
    There is a spectrum of severity for AKI. For example, some 
individuals may not know they are experiencing AKI without a serum or 
urine test. There is also a spectrum of time and medical treatment 
needed for recovery, dependent on whether the AKI is quickly reversed 
or sustained for longer periods of time. In Schlader et al. 2017, 
researchers noted that the biomarkers of AKI for participants in their 
trial returned to baseline the following day. However, intrarenal 
causes of AKI may require longer periods of time for recovery and may 
potentially require the need for medication or dialysis (Goyal et al., 
2023). AKI can be severe, which can be the case when resulting from 
heat stroke, where it may represent irreversible damage to the kidneys 
and can be fatal (Roberts et al., 2008; King et al., 2015; Wu et al., 
2021). Recurrent AKI may also lead to chronic kidney disease (as 
discussed in Section IV.M.IV., Chronic Kidney Disease).
G. Summary
    The available peer-reviewed scientific literature, both 
experimental and observational studies, suggests that occupational heat 
exposure causes AKI among workers. However, there are limitations in 
the case definitions used to define AKI in observational settings.
IV. Chronic Kidney Disease
A. Introduction
    Chronic kidney disease (CKD) is a progressive disease characterized 
by a gradual decline in kidney function over months to years. It is 
typically asymptomatic or mildly symptomatic until later stages of the 
disease, when symptoms such as edema, weight loss, nausea, and vomiting 
can occur (NIDDK 2017d). People with CKD can be at a greater risk for 
other health conditions, like AKI, heart attacks, hypertension, and 
stroke. The diagnosis typically requires multiple blood and urine tests 
taken over time (NIDDK 2016). Typical risk factors for CKD include 
hypertension and diabetes.
    Epidemics of CKD in Central America and other pockets of the world, 
such as India and Sri Lanka, that appear to be afflicting mostly young, 
outdoor workers with no history of hypertension or diabetes have raised 
questions about

[[Page 70724]]

whether working in hot conditions can cause the development of CKD 
(Johnson et al., 2019). Researchers have been investigating this 
question and the cause of the epidemic over the past 20 years, 
including other potential exposures, such as heavy metals, 
agrichemicals, silica, and infectious agents (Crowe et al., 2020).
B. Physiological Mechanisms
    Researchers have proposed that working in the heat could lead to 
the development of CKD through repetitive AKI events (see discussion of 
heat-related mechanisms in Section IV.M.III., Acute Kidney Injury). 
However, some researchers acknowledge the possibility that the 
unexplained CKD cases observed in Central America and elsewhere may 
instead represent a chronic disease process that begins earlier in life 
which places workers at increased risk of AKI (Johnson et al., 2019; 
Schlader et al., 2019). Additionally, as discussed above in Section 
IV.M.III., Acute Kidney Injury, some occupational cases of AKI could be 
transient, the result of prerenal causes, and possibly unrelated to the 
development of CKD.
    Independent of the epidemic of unexplained CKD, frequent and/or 
severe AKI has been identified as a risk factor for developing CKD 
(Ishani et al., 2009; Coca et al., 2012; Chawla et al., 2014; Hsu and 
Hsu 2016; Heung et al., 2016). The relationship between heat-related 
AKI and risk of developing CKD is untested in the experimental 
literature because of the ethical implications (Schlader et al., 2019; 
Hansson et al., 2020).
    As discussed in Section IV.E., Heat Stroke, there is also evidence 
that experiencing heat stroke may increase an individual's risk of 
developing CKD (Wang et al., 2019; Tseng et al., 2020).
C. Identifying Cases of Chronic Kidney Disease
    As discussed previously in the context of AKI, serum creatinine is 
commonly used to estimate glomerular filtration rate (GFR), the 
indicator of kidney function. When measures of serum creatinine (and 
therefore estimates of GFR) are taken over periods of months to years, 
medical professionals can determine if an individual's kidney function 
is declining. CKD is typically diagnosed when the estimated GFR is 
below a rate of 60 mL/min/1.73m\2\ for at least 3 months, although 
there are other indicators, like a high albumin-to-creatinine ratio. 
There are various stages of CKD; the final stage is called end-stage 
renal disease (ESRD) and represents a point at which the kidneys can no 
longer function on their own and require dialysis or transplant.
D. Observational Evidence
    There is a growing body of evidence that suggests that heat-exposed 
workers who experience AKI (or short-term fluctuations in serum 
creatinine) are at greater risk of experiencing declines in kidney 
function over a period of months to years. For instance, sugarcane 
workers in Nicaragua who experienced cross-shift increases (i.e., 
increase from pre-shift to post-shift) in serum creatinine at the 
beginning of the harvest season were more likely to experience declines 
in estimate GFR nine weeks later (Wesseling et al., 2016). Another 
study conducted among Nicaraguan sugarcane workers found that 
approximately one third of workers who experienced AKI during the 
harvest season had newly decreased kidney function (greater than 30% 
decline) and a measure of estimated GFR of less than 60 mL/min/1.73m2 
one year later (Kupferman et al., 2018). In an analysis among 
Guatemalan sugarcane workers, Dally et al. found that workers with 
severe fluctuations in serum creatinine over a period of 6 workdays had 
greater declines in estimated GFR (-20% on average) (Dally et al., 
2020). In a separate study conducted in Northwest Mexico, researchers 
observed declines in estimated GFR among migrant and seasonal farm 
workers from March to July that were not observed in a reference group 
of office workers in the same region (L[oacute]pez-G[aacute]lvez et 
al., 2021).
    Further support for the hypothesis that working in the heat may 
lead to declines in GFR and increased risk of CKD comes from 
intervention studies in Central America, in which workers were given 
water-rest-shade interventions and observed longitudinally for kidney 
outcomes. In these studies, implementation of the heat stress controls 
was associated with reductions in the declines in kidney function and 
reduced rates of kidney injury (Glaser et al., 2020; Wegman et al., 
2018).
    While much of the literature is focused on Central American 
workers, OSHA did identify one paper conducted among a cohort of U.S. 
firefighters. Pinkerton et al. (2022) found lower than expected rates 
of ESRD in the cohort (relative to the general U.S. population) despite 
high levels of occupational exposure to heat. However, as the authors 
point out, this may be due to the healthy worker effect (i.e., a 
phenomenon in occupational epidemiology by which workers appear to be 
healthier than the general population due to individuals with health 
conditions leaving the workforce) (Pinkerton et al., 2022). The authors 
also examined associations between proxies for heat exposure and risk 
of developing ESRD and found non-significant associations between the 
number of exposed days and all-cause ESRD, systemic ESRD, and 
hypertensive ESRD. Very few of the ESRD cases identified in this cohort 
were due to interstitial nephritis (which would be most consistent with 
the CKD cases observed in Central America), limiting the authors' 
ability to examine associations between those cases and exposure.
    There may be differences between the heat-exposed worker 
populations in Central America and the U.S. that could limit the 
ability to extrapolate findings from that region, such as differences 
in other potentially nephrotoxic exposures (e.g., agrichemicals, 
infectious agents). There is also evidence that children in regions 
with epidemics of unexplained CKD have signs of kidney injury (Leibler 
et al., 2021). Unfortunately, surveillance of CKD in the U.S. (namely 
the U.S. Renal Data System) may be missing cases among susceptible 
workers, such as migrant agricultural workers, limiting the ability to 
detect a potential epidemic of heat-related CKD in this country.
    In addition to the general lack of studies conducted among U.S. 
workers, there may be other limitations with these observational 
studies, such as limited data on longer-term follow-up (i.e., years 
instead of months) and the potential for reverse causality (i.e., 
undetected CKD is causing AKI).
E. Treatment and Recovery
    Often kidney disease gets worse over time and function continues to 
decline as scarring occurs (NIDDK 2017d). As discussed above, late-
stage CKD (or ESRD) requires dialysis or a kidney transplant for an 
individual to survive. Kidney failure is permanent. Having even early-
stage CKD may impair workers' urine concentrating ability, which could 
increase their heat strain and risk of HRIs while working (Petropoulos 
et al., 2023).
F. Summary
    There is growing evidence suggesting that heat stress and 
dehydration may be contributing to an epidemic of CKD among workers in 
Central America and other parts of the world, although the cause is 
still being investigated by researchers. There is currently limited 
information as to whether this type of CKD is affecting U.S. workers 
and if so, to what extent. Experiencing heat stroke has been identified 
in the literature as a risk factor for developing CKD.

[[Page 70725]]

N. Other Health Effects

I. Introduction
    In addition to the health effects discussed in the previous sub-
sections, heat exposures have also been linked to reproductive health 
effects. Additionally, health effects have been associated with prior 
episodes of heat illness.
II. Reproductive and Developmental Health Effects
    There is mixed evidence that heat affects reproductive and 
developmental health outcomes. NIOSH reported two mechanisms by which 
heat may affect reproductive and developmental health: infertility 
(e.g., such as through damaged sperm) and teratogenicity (harm to the 
developing fetus, e.g., spontaneous abortion or birth defects) (NIOSH, 
2016). NIOSH concluded that while human data about reproductive risks 
at exposure limits (see NIOSH, 2016, table 5-1, p. 70) were limited, 
results of research and animal experiments support the conclusion heat-
related infertility and teratogenicity are possible (NIOSH, 2016, p. 
91).
    More recent evidence, although also limited, continues to provide 
support of a reproductive risk to people who are pregnant and 
developmental risk to their children. Numerous epidemiological studies 
have reported that heat exposure during pregnancy is associated with 
poor outcomes, such as pre-term labor and birth and low-birth weight 
babies (e.g., Kuehn and McCormick, 2017; Basu et al., 2018; Chersich et 
al., 2020; Rekha et al., 2023). While most studies assess this 
relationship in the general population of pregnant women and do not 
specifically address occupational exposures, Rekha et al. show that 
occupational exposures to heat were associated with adverse pregnancy 
and fetal outcomes, as well as adverse outcomes during birth in a 
cohort of pregnant women in Tamil Nadu, India (Rekha et al., 2023). 
Although the mechanisms for these outcomes are unclear, a study of 
pregnant women conducting agricultural work or similar activities for 
their homes in The Gambia reported an association between heat exposure 
and fetal strain (through measures of fetal heart rate and umbilical 
artery resistance) (Bonell et al., 2022). Further, a recent 
longitudinal prospective cohort study in Germany found that heat 
exposure was associated with vascular changes in the uterine artery. 
This study reports that changes of increased placental perfusion and 
decreased peripheral resistance in the uterine artery indicate blood 
redistribution to the fetus during the body's response to heat stress. 
They also report increased maternal cardiovascular strain. This data 
may support a mechanistic role for uterine and placental blood flow 
changes during heat exposures in resultant birth outcomes, such as pre-
term birth (Yuzen et al., 2023; Bonell et al., 2022).
    There is evidence that occupational heat exposures can affect male 
reproductive health (e.g., Mieusset and Bujan, 1995). Some research 
studies report associations between occupational heat exposure and time 
to conceive (e.g., Rachootin and Olsen, 1983; Thonneau et al., 1997), 
sperm velocity (Figa-Talamanca et al., 1992), and measures of semen 
quality such as sperm abnormalities (Rachootin and Olsen, 1983; Bonde, 
1992; Figa-Talamanca et al., 1992; De Fleurian et al., 2009). Effects 
of heat on sperm have also been demonstrated in experiments in animal 
models (Waites, 1991). Cao et al. report that in their study of heat 
stress in mice, heat stress reduced sperm count and motility (Cao et 
al., 2023). In this study, the heat exposed mice were exposed to 
38[deg]C (100.4 [deg]F) temperatures for 2 hours per day for two weeks. 
When the mice were not being exposed to heat, they were kept at 
25[deg]C (77 [deg]F). Control mice were kept at 25[deg]C for the 
duration of the study. Their study results indicate that reduced sperm 
quality may be a result of disrupted testicular microbial environment 
and disruption in retinol metabolism that occurs during heat stress. 
Although, the authors note that the heat exposure does not accurately 
mimic real world heat exposures in humans.
    While it is accepted that heat impairs spermatogenesis, or 
development of sperm (e.g., MacLeod and Hotchkiss, 1941; Mieusset et 
al., 1987; Thonneau et al., 1997), some studies of occupational heat 
exposure find no relationship between heat and semen quality (Eisenberg 
ML et al., 2015). Another study found observable but not statistically 
significant associations between heat and semen quality (Jurewicz et 
al., 2014). Many studies of the effects of occupational heat exposure 
on reproductive outcomes are cross-sectional in nature and measure 
exposures through occupation categories or self-report answers on 
questionnaires (e.g., Figa-Talamanca et al., 1992; Thonneau et al., 
1997; Jurewicz et al., 2014). These methods can be susceptible to 
recall bias and misclassification errors, which can reduce accuracy in 
characterizing the association between occupational heat exposures and 
reproductive health outcomes, and they are also unable to determine 
causality on their own. Additional research that quantifies 
occupational heat exposures directly (e.g., through measures of heat 
strain or on-site temperatures) would help to clarify the impacts of 
occupational heat exposures on male reproductive outcomes.
III. Health Effects Associated With Prior Episodes of Heat Illness
    A limited number of studies have focused on a variety of long-term 
effects following a prior episode of heat illness. This includes 
research by Wallace et al., also reviewed by NIOSH in the 2016 Criteria 
for a Recommended Standard Occupational Exposure to Heat and Hot 
Environments, whose retrospective case control study of military 
members found that those who experienced an exertional heat illness 
event earlier in life were more likely to die due to cardiovascular or 
ischemic heart disease (Wallace et al., 2007). Similarly, Wang et al. 
reports that, in their retrospective cohort study in Taiwan, prior heat 
stroke was associated with a higher incidence of acute ischemic stroke, 
acute myocardial infarction, and an almost three-fold higher incidence 
of chronic kidney disease compared to patients who had other forms of 
heat illness or compared to the control group that had no prior heat 
illness, over the study's 14 year follow-up period (Wang et al., 2019). 
They also found significantly higher incidence of cardiovascular 
events, cardiovascular disease, and chronic kidney disease among 
individuals in the study who had other forms of heat illness (heat 
syncope, heat cramps, heat exhaustion, heat fatigue, heat edema and 
other unspecified effects) compared to the control group that had no 
prior heat illness. In a long-term follow-up study of military 
personnel who had experienced exertional heat illness, Phinney et al. 
reported a transient and small but observable increase in the rate of 
subsequent hospitalizations and decreased retention in the military 
(Phinney et al., 2001). While these studies suggest a relationship 
between episodes of serious heat illness and subsequent health effects, 
this body of research is small and subject to some limitations. The 
cross-sectional nature of some of these studies does not allow for 
determination of causality on their own. Additionally, given the 
retrospective nature of some of these studies it is possible that 
important confounding variables were not adjusted for in analyses, 
including occupation in some cases.

[[Page 70726]]

IV. Summary
    The description of evidence presented here demonstrates that there 
is some evidence to support a link between occupational heat exposures 
and adverse reproductive health outcomes. There is also limited 
evidence that prior episodes of heat illness may affect health outcomes 
later in life such as increased risk of cardiovascular disease and 
kidney diseases. This evidence of reproductive and developmental health 
effects and health effects associated with prior episodes of heat 
illness, while suggestive, is still nascent and requires further 
investigation.

O. Factors That Affect Risk for Heat-Related Health Effects

I. Introduction
    This section discusses individual risk factors for heat-related 
injury and illness. The purpose of this discussion is to summarize the 
factors that may exacerbate the risk of workplace heat-related hazards 
and to provide information to better inform workers and employers about 
those hazards. However, exposure to workplace heat contributes to heat 
stress for all workers and can be detrimental to workers' health and 
safety regardless of individual risk factors. OSHA is not suggesting 
that application of the proposed standard would depend on an employer's 
knowledge or analysis of these factors for their individual workers. 
Nor do these individual risk factors detract from the causal link 
between occupational exposure to heat and adverse safety and health 
outcomes or an employer's obligation to address that occupational risk 
(see Reich v. Arcadian Corp., 110 F.3d 1192, 1198 (5th Cir. 1997) 
(Congress intended the Act to protect all employees, ``regardless of 
their individual susceptibilities''); Pepperidge Farm, Inc., 17 O.S.H. 
Cas. (BNA) ] 1993 (O.S.H.R.C. Apr. 26, 1997) (that non-workplace 
factors may render some workers more susceptible to causal factors does 
not preclude finding the existence of an occupational hazard); see also 
Bldg. & Const. Trades Dep't, AFL-CIO v. Brock, 838 F.2d 1258, 1265 
(D.C. Cir. 1988) (holding that OSHA did not err in including smokers in 
its analysis of the significant risk posed by occupational exposure to 
asbestos, despite the ``synergistic effects'' of smoking and 
asbestos)). Many factors can influence an individual's risk of 
developing heat-related health effects. These factors include variation 
in genetics and physiology, demographic factors, certain co-occurring 
health conditions or illnesses, acclimatization status, certain 
medications and substances, and structural factors (e.g., economic, 
environmental, political and institutional factors) that lead to 
disproportionate exposures and outcomes. Although there is a lack of 
evidence that explores the full extent to which these factors interact 
to affect heat-related health effects, or how various risk factors 
compare in their impacts, there is evidence that each of these factors 
can affect risk of heat-related health effects. This section focuses on 
factors that relate to an individual's health status. For an in-depth 
discussion on acclimatization as a risk factor, see Section V., Risk 
Assessment, and for an in-depth discussion on demographic factors and 
structural factors that affect risk of heat-related illness, see 
Section VIII.I., Distributional Analysis.
II. Risk Factors
    There are a number of factors that can impact an individual's 
response to heat stress and lead to variation in heat stress response 
between individuals. These include variation in genotype (Heled et al., 
2004), gene expression (Murray et al., 2022), body mass and differences 
in thermoregulation between the biological sexes (Notley et al., 2017), 
differences in thermoregulation as people age (e.g., Pandolf 1997, 
Kenny et al., 2010; Kenny et al., 2017), and pregnancy (Wells, 2002; 
NIOSH, 2016). Normal variation across individuals in genetics, 
physiology, and body mass results in variation in how individuals 
respond to heat stress. There is some evidence that, at least in some 
specific populations, variation in genotype (i.e., genetic makeup) can 
affect heat storage and heat strain (Heled et al., 2004; Gardner et 
al., 2020). Normal variation in body mass can also correspond to 
variation in thermoregulation between individuals (e.g., Havenith et 
al., 1998). Results from Havenith et al.'s experimental study of heat 
stress under different climate and exercise types indicates that one 
reason for this effect may be due to the relationship between size and 
surface area of the skin which plays an important role in cooling 
capacity (Havenith et al., 1998). A more detailed discussion of the 
relationship between obesity and heat stress response can be found 
below.
    There is some evidence that biological sex could be considered a 
risk factor for heat-related illness, although the evidence is mixed. 
Some studies find differences in heat stress response between males and 
females (e.g., Gagnon et al., 2008; Gagnon and Kenny, 2011; Gagnon and 
Kenny, 2012). These differences may be due to differences in body mass 
(Notley et al., 2017), lower sweat output in females or differences in 
metabolic heat production (Gagnon et al., 2008; Gagnon and Kenny, 
2012). However, recent experimental data assessing differences in 
thermoeffector responses (autonomic responses that affect 
thermoregulation, such as skin blood flow and sweat rate) between males 
and females exposed to exercise show that differences between the sexes 
in heat stress response are mostly explained by differences in 
morphology (body shape and size and the resultant mass-surface ratios) 
(Notley et al., 2017). Although, Notley et al.'s (2017) experiment only 
involved heat environments where enough heat could be lost so that the 
body does not continue to gain heat (compensable heat stress), so it is 
unclear if an increased effect due to biological sex would occur in 
conditions where heat gain is expected, such as in occupational 
settings where environmental heat or environmental heat and exertion 
exceed the body's ability to cool.
    Healthy aging processes can also make individuals more susceptible 
to heat-related illness. Aging may impact thermoregulation through 
reduced cardiovascular capacity (Minson et al., 1998; Lucas et al., 
2015), reduced cutaneous vasodilation (the widening of blood vessels at 
the skin to aid heat loss), sweat rate, altered sensory function 
(Dufour and Candas, 2007; Wong and Hollowed, 2017), and changes in 
fluid balance and thirst sensation (Pandolf, 1997). Observational 
evidence tends to show that elderly individuals, particularly those 
with co-existing chronic or acute diseases, are at highest risk for 
morbidity or mortality related to heat exposures, and that risk 
increases with age (e.g., Semenza et al., 1999; Fouillet et al., 2006; 
Knowlton et al., 2008). However, experimental evidence shows that, 
under certain conditions, when individuals are matched for fitness 
level and body build and composition, middle-aged individuals can 
compensate for heat exposures similarly to younger adults (Lind et al., 
1970; Pandolf, 1997, Kenny et al., 2017). Conversely, observational 
studies of occupational populations often find that younger workers 
experience greater rates of heat-related illness than do older workers 
(e.g., Harduar Morano et al., 2015; Hesketh et al., 2020; Heinzerling 
et al., 2020). While it is unclear why younger workers appear to have 
greater rates of heat-related illness in epidemiological data, 
Heinzerling et al. (2020) suggest that this could be a result of a 
greater number of younger workers being

[[Page 70727]]

employed in high-risk occupations. Further, younger workers have less 
work experience, meaning that younger workers are less familiar with 
the heat risks associated with their jobs, how their body responds to 
heat, and/or how to respond if they experience symptoms of heat-related 
illness.
    Health status is another factor that plays a role in how someone 
responds to heat stress (e.g., Semenza et al., 1999; Knowlton et al., 
2008; NIOSH, 2016; Vaidyanathan et al., 2019, 2020). Conditions such as 
cardiovascular disease and diabetes can affect risk of heat-related 
illness (e.g., Kenny et al., 2016; Kenny et al., 2018). The 
cardiovascular system plays an integral role in thermoregulation and 
heat stress response (Costrini et al., 1979; Lucas et al., 2015; Wong 
and Hollowed, 2017; Kenny et al., 2018). Cardiovascular diseases can 
affect the heart and blood vessels, increasing cardiovascular strain 
and decreasing cardiovascular function and thermoregulatory capacity 
(Kenny et al., 2010) and, as a result, increase risk of heat-related 
illness during heat stress (Kenny et al., 2010; Semenza et al., 1999). 
For example, people with hypertension (i.e., high blood pressure) may 
be at increased risk of heat-related illness due to changes in skin 
blood flow that can impair heat dissipation during heat stress (Kenny 
et al., 2010). Further, many individuals with hypertension and 
cardiovascular diseases may take prescription medications that reduce 
thermoregulatory functions, through mechanisms like reduced blood flow 
to the skin, which can increase sensitivity to heat (Wee et al., 2023). 
Studies estimate that a substantial percentage of the population, and 
therefore the population of workers, have the type of health status 
(i.e., having a chronic condition such as cardiovascular diseases) 
(Boersma et al., 2020; Watson et al., 2022) that could affect their 
response to heat stress. For example, Watson et al. (2022) estimate 
that of the 46,781 surveyed adults between the ages of 18 and 34 who 
reported being employed, 26.1% have obesity, 11% have high blood 
pressure, and 9.7% have high cholesterol. Additionally, 19.4% were 
estimated to have depression, which is sometimes treated with 
medications that can affect thermoregulation.
    Diabetes and obesity are other factors that may affect risk of 
developing heat-related illness (Kenny et al., 2016). Both diabetes and 
obesity may affect thermoregulation by reducing a person's ability to 
dissipate heat through changes in skin blood flow and sweat response 
(Kenny et al., 2016). While some evidence shows that individuals with 
well-controlled diabetes may be able to maintain normal 
thermoregulatory capacity (Kenny et al., 2016), some evidence indicates 
that individuals with poorly controlled diabetes (Kenny et al., 2016) 
or older individuals with Type 2 diabetes (Notley et al., 2021) may 
experience decreased heat tolerance. Obesity has also been identified 
as a risk factor for exertional heat illness in the military (e.g., 
Bedno et al., 2014; Nelson et al., 2018b; Alele et al., 2020). Gardner 
et al. (1996) reported increasing risk of exertional heat illness among 
male Marine Corps recruits as BMI increased. Additionally, a smaller 
body mass to surface area ratio can reduce capacity for heat loss since 
surface area is relatively smaller in relationship to mass (Bar-Or et 
al., 1969; Kenny et al., 2016). Differences in tissue properties 
between adipose (fat) tissue and other body tissues may indicate that a 
higher body fat mass can lead to greater rises in core temperature for 
a given amount of heat storage in the body (Kenny et al., 2016).
    Beyond chronic health conditions, prior episodes of significant 
heat-related illness and recent or concurrent acute illness or 
infection may also affect an individual's response to heat stress and 
increase the risk of heat-related illness (e.g., Carter et al., 2007; 
Nelson et al., 2018a; Nelson et al., 2018b; Alele et al., 2020). 
Reviews of research and case studies of heat-related illness indicate 
that acute illnesses that may affect risk of heat-related illness 
include upper respiratory infections and gastrointestinal infections 
(Casa et al., 2012; Alele et al., 2020). However, statistical evidence 
is limited (Alele et al., 2020). Leon and Kenefick (2012) discuss 
results from a study of four marine recruits who presented with 
exertional heat illness and who also had an acute illness separate from 
heat-related illness. The recruits' blood tests showed elevated levels 
of immune-related substances which Leon and Kenefick identify as being 
substances that are both mediators of viral infection symptoms and 
substances associated with exertional heat illness. Leon and Kenefick 
interpret this observation, along with evidence from a study on rats 
that showed that bacteria exposure exacerbated inflammation and organ 
dysfunction due to heat stress, to suggest that pre-existing 
inflammatory states, such as those that occur with acute viral illness, 
compromise the ability to thermoregulate appropriately (Carter et al., 
2007; Leon and Kenefick, 2012) (see also Bouchama and Knochel, 2002). 
Several studies in military populations also show that a prior heat 
illness may increase risk of a future episode of heat illness (Nelson 
et al., 2018b; Alele et al., 2020). Assessments of heat and epigenetics 
(the study of how the environment and behavior affects genes) suggest 
that the complex physiological responses to heat impact genetic 
mechanisms that could play a role in increasing susceptibility to 
future heat illness following an episode of heat illness (Sonna et al., 
2004; Murray et al., 2022).
    Certain medications can also affect thermoregulation and risk of 
heat-related illness. Medications that may decrease thermoregulatory 
capability include medications that treat cardiovascular diseases, 
diabetes, neuropsychiatric diseases, neurological diseases, and cancer 
(Wee et al., 2023). Some of these medications affect thermoregulation 
by directly affecting the region of the brain that controls 
thermoregulation or through other central nervous system effects (e.g., 
antipsychotics, dopaminergics, opioids, amphetamines) (Cuddy, 2004; 
Stollberger et al., 2009; Musselman and Saely, 2013; Gessel and Lin, 
2020; Wee et al., 2023). Other medications affect thermoregulation 
through effects on heat dissipation that occur due to changes in sweat 
response and/or blood flow to the skin (e.g., anticholinergics, 
antihypertensives, antiplatelets, some antidepressants and 
antihistamines, aspirin) (see, e.g., Freund et al., 1987; Cuddy, 2004; 
Stollberger et al., 2009; Wee et al., 2023; CDC, 2024b). There are also 
medications that may affect ability to perceive heat and exertion 
(e.g., dopaminergics) (Wee et al., 2023). Some medications can affect 
electrolyte balances (e.g., diuretics, beta-blockers, calcium channel 
blockers, and antacids) (CDC, 2024b). When accompanied by dehydration, 
some medications also pose a toxicity risk (e.g., apixaban, lithium, 
carbamazepine) (CDC, 2024b). Finally, some medications can affect fluid 
volume, kidney function, hydration status, thirst perception, or 
cardiac output (e.g., diuretics, ACE inhibitors, some anti-diabetics, 
beta-blockers, non-steroidal anti-inflammatories (NSAIDs), tricyclic 
antidepressants, laxatives, and antihistamines) (Stollberger et al., 
2009; Wee et al., 2023; CDC, 2024b). The NIOSH Criteria for a 
Recommended Standard for Occupational Exposure to Heat and Hot 
Environments (table 4-2), the Department of the Army's Technical 
Bulletin 507 (table 4-2), and CDC's Heat and Medications--Guidance for 
Clinicians contain additional information about classes of

[[Page 70728]]

medications and the proposed mechanisms for how they affect 
thermoregulation (NIOSH, 2016; Department of the Army, 2022; CDC, 
2024b).
    Medications that can affect how individuals respond to heat are 
used by a significant portion of the U.S. population. Survey data from 
the National Health and Nutrition Examination Survey from 2015-2016 
showed that 60% of adults aged 40-79 used a prescription medication 
within the last thirty days and approximately 22% of adults in that 
same age range took five or more prescription medications (Hales et 
al., 2019). Many of the medications reported by survey respondents are 
medications that can affect an individual's response to heat (e.g., 
commonly used blood pressure and diabetes medications).
    Amphetamines (whether prescription or illicit), methamphetamines, 
and cocaine can also affect thermoregulation and increase risk of heat-
related illness (NIOSH, 2016; Department of the Army, 2022). These 
substances can affect the central nervous system's thermoregulatory 
functions, stimulate heat generation, and reduce heat dissipation 
through vasoconstriction (Cuddy, 2004). The synergy between the 
hyperthermia induced by these substances, physical activity, and heat 
exposure can increase risk of heat-related illness (Kiyatkin and 
Sharma, 2009). Analyses of occupational heat-related fatalities find 
amphetamines and methamphetamines to be an important risk factor 
(Tustin et al., 2018a, Karasick et al., 2020; Lin et al., 2023). In Lin 
et al.'s 2023 review of heat-related hospitalizations and fatalities 
documented through NIOSH Fatalities in Oil and Gas Database (2014-2019) 
and OSHA's Severe Injury Report Database (2015-2021), 50% of identified 
fatalities occurred in workers that had tested positive for 
amphetamines or methamphetamines after they died. However, small sample 
sizes, sampling strategies, and incomplete data have so far limited the 
ability of studies to fully characterize the association between these 
substances and risk of heat-related illness or fatality. Poor data 
quality or limited data has also limited current studies from 
concluding if and when amphetamine-like substances are from 
prescription or non-prescription use.
    Alcohol and caffeine use may also affect risk of heat-related 
illness through effects on hydration status and heat tolerance (NIOSH, 
2016; Tustin, 2018; Department of the Army, 2022). There have been 
cases of fatalities due to occupational heat exposure in individuals 
with a history of ``alcohol abuse or high-risk drinking'' (Tustin et 
al., 2018a, p. e385). Both alcohol and caffeine may affect how someone 
responds to heat stress due to their ability to cause loss of fluids 
and subsequently dehydration, and alcohol also affects central nervous 
system function (NIOSH, 2016). In the case of caffeine, it appears that 
moderate consumption associated with normally caffeinated beverages 
(e.g., one cup of coffee, tea, soda) may not interfere with 
thermoregulation in a way that negatively affects response to heat 
stress (NIOSH, 2016; Kazman et al., 2020; Department of the Army, 
2022). However, heavily caffeinated beverages, such as energy drinks, 
have been linked to negative health outcomes (Costantino et al., 2023) 
and could potentially exacerbate heat stress through diuretic (salt and 
water loss) mechanisms and cardiovascular strain (NIOSH, 2016). 
Overall, there is a lack of robust data that quantify the specific 
amounts of alcohol or caffeine that are problematic for heat stress 
response. However, experts generally advise against drinking alcohol or 
caffeinated beverages before or during work or exercise in the heat 
(NIOSH, 2016; Department of the Army, 2022; CDC, 2022).
III. Summary
    The evidence presented in this section demonstrates that there are 
numerous factors that can affect risk of heat-related illness (e.g., 
genetics, age, body mass, some chronic conditions, prescription 
medications and drugs). Because prevalence data show that a majority of 
working-age adults live with or experience at least one risk factor, 
these factors should be considered an important component of 
understanding how individuals can be at increased risk for heat-related 
illness. OSHA acknowledges, however, that for most of the described 
risk factors, the evidence is not robust enough to determine the full 
picture of how the factor impacts risk of heat-related illness or to 
establish the degree to which the risk factor contributes to overall 
risk of developing heat-related illness. There is also a lack of 
evidence evaluating the way in which multiple risk factors combine to 
affect risk of heat-related health outcomes.

P. Heat-Related Injuries

I. Introduction
    In addition to heat-related illnesses, heat exposure can lead to a 
range of occupational heat-related injuries. A heat-related injury 
means an injury, such as a fall or cut, that is linked to heat 
exposure. A heat-related injury may occur as a result of a heat-related 
illness, such as a fracture following heat syncope. The association 
between heat exposure and heat-related injury among workers has been 
well documented over the last decade (Tawatsupa et al., 2013; Xiang et 
al., 2014b; Adam-Poupart et al., 2015; Spector et al., 2016; McInnes et 
al., 2017; Calkins et al., 2019; Dillender, 2021; Dally et al., 2020; 
Park et al., 2021; Negrusa et al., 2024). In particular, analyses of 
workers' compensation claim data has demonstrated the increased risk of 
occupational traumatic injury with increasing heat exposure (Xiang et 
al., 2014b; Adam-Poupart et al., 2015; Spector et al., 2016; McInnes et 
al., 2017; Calkins et al., 2019; Dillender, 2021; Park et al., 2021; 
Negrusa et al., 2024). These types of heat-related injuries can cause 
hospitalizations, extended time out of work, and reduced productivity. 
In some instances, a heat-related injury may be fatal, like in the 
event of accidents such as a slip, trip, or fall. In 1972, NIOSH 
identified occupational heat exposure as contributing to workplace 
injuries, and discussed how accidents and injuries were outcomes that 
could be prevented by a heat stress standard (NIOSH, 1972). 
Specifically, NIOSH highlighted how reduced physical and psychological 
performance, fatigue, accuracy of response, psychomotor performance, 
sweaty palms, and impaired vision may result in a workplace heat-
related injury.
    Since multiple types of injuries can be heat-related (e.g., strain, 
fracture, crushing) and the mechanisms underlying those injuries vary 
(e.g., impaired speed and reaction time, impaired vision, impaired 
dexterity), the identification and classification of heat-related 
injuries varies on a case-by-case basis. Although there are no ICD or 
OIICS codes specific to diagnosing heat-related injuries, medical 
professionals and occupational health professionals can combine a heat-
related illness code with other injury related codes to indicate an 
injury is heat-related. An injury specifically attributed to heat would 
be expected to be assigned both a heat-related OIICS or ICD code and an 
injury OIICS or ICD code. Numerous researchers have used ICD and OIICS 
code to conduct studies on heat-related injuries (Dillender, 2021; 
Garzon-Villalba et al., 2016; Morabito et al., 2006; Spector et al., 
2016).
    This section first presents the epidemiological evidence of 
increasing occupational injuries during periods of hotter temperatures, 
followed by a discussion of mechanisms that can lead to heat-related 
injuries.

[[Page 70729]]

II. Occupational Heat-Related Injuries
    A multitude of studies have identified an association between heat 
exposure and occupational injury in the U.S. (Knapik et al., 2002; 
Fogleman et al., 2005; Garzon-Villalba et al., 2016; Spector et al., 
2016; Calkins et al., 2019; Dillender, 2021; Park et al., 2021; Negrusa 
et al., 2024). These analyses primarily rely on workers' compensation 
claim data and meteorological data and are often case-crossover or 
observational time-series in design.
    In two studies of outdoor agricultural workers (Spector et al., 
2016) and outdoor construction workers (Calkins et al., 2019) in 
Washington State, traumatic injury claims were significantly associated 
with heat exposure. Among outdoor agricultural workers (n=12,213 
claims), Spector et al. (2016) found a statistically significant 
increased risk of traumatic injuries at a daily maximum humidex (the 
apparent, or ``feels like,'' temperature calculated from air 
temperature and dew point, similar to heat index) above 25 [deg]C (77 
[deg]F). Among outdoor construction workers (n=63,720 claims), Calkins 
et al. (2019) found an almost linear statistically significant 
association between traumatic injury risk and humidex. Both studies 
reported that injuries most commonly resulted from falls or bodily 
reaction and exertion, which may include sudden occurrences of strains, 
sprains, fractures, or loss of balance, among others (Spector et al., 
2016; Calkins et al., 2019).
    Using workers' compensation claim data from Texas, Dillender (2021) 
found that hotter temperatures resulted in larger percent increases in 
traumatic injuries among two similar sets of injury types, ``open 
wounds, crushing injuries, and factures'' and ``sprains, strains, 
bruises, and muscle issues.'' Park et al. (2021) examined over 11 
million workers' compensation records in California and estimated that 
approximately 20,000 additional injuries per year between 2001 and 2018 
were related to hotter temperatures. In comparison to a day with 
temperatures in the 60s [deg]F, the risk of occupational heat-related 
injury increased by 5-7% (p<0.05) and 10-15% (p<0.05) on days with high 
temperatures between 85-90 [deg]F and above 100 [deg]F, respectively 
(Park et al., 2021).
    In these case-crossover studies, cases serve as their own controls, 
allowing for variables such as age, sex, race, and ethnicity, as well 
as other known and unknown time-invariant confounders to be controlled. 
However, there are still some limitations to these studies, such as the 
potential for time-varying confounders (e.g., air pollutants like ozone 
and sleep duration influenced by nighttime temperatures).
    Studies conducted among workers outside the U.S. have also reported 
a relationship between working in the heat and increased risk of 
injuries (Morabito et al., 2006; Tawatsupa et al., 2013; Adam-Poupart 
et al., 2015; McInnes et al., 2017; Martinez-Solanas et al., 2018). 
Analyses from Dally et al. (2020), found an increase in injury risk 
with increasing average daily mean WBGT above 30 [deg]C (86 [deg]F) 
among sugarcane harvesters in Guatemala; although this result was not 
statistically significant, this may have been due to small sample and 
event size.
III. Mechanisms
    Heat exposure can impair workers' psychomotor and mental 
performance, which can interfere with routine occupational tasks. 
Consequently, the risk of work-related injuries, including slips, 
trips, and falls, as well as cuts and other traumatic injuries, is 
exacerbated when job tasks are performed in hot environments. As 
summarized in the prior health effects sections of this preamble, heat 
can impair a variety of physiological systems and produce a range of 
symptoms. Changes in the cardiorespiratory, locomotor, and nervous 
systems due to heat exposure can induce various bodily responses such 
as fatigue, which may lead to injury (Ross et al., 2016). Changes from 
elevated skin and core body temperatures, which may result in increased 
sweating and dehydration, can cause decrements in physical, visuomotor, 
psychomotor, and cognitive performance (Grandjean and Grandjean, 2007; 
Lieberman, 2007). Even experiencing a high level of heat sensation may 
contribute to discomfort and distress, causing distraction and other 
behavioral changes that can result in accidents and injuries (Simmons 
et al., 2008). An explanation of how heat exposure can impair 
psychomotor and mental performance, and consequently lead to 
occupational heat-related injuries is provided below.
A. Impaired Psychomotor Performance
    Heat exposure can impair psychomotor function (i.e., the connection 
between mental and muscle functions) which may cause heat-related 
injuries. Impaired psychomotor function from heat exposure can take 
multiple forms, including impaired movement, strength, or coordination 
(fatigue); impaired postural stability and balance; and impaired 
accuracy, speed, and reaction time. Each of these impairments to 
psychomotor performance are discussed in turn below.
I. Impaired Movement, Strength, or Coordination (Fatigue)
    Heat exposure can hamper psychomotor performance by impairing 
workers' movement, strength, or coordination and causing fatigue. 
Fatigue has been described as having a lack of energy or a feeling of 
weariness or tiredness (NIOSH, 2023b). Effects from heat strain on the 
cardiorespiratory and locomotor systems can cause both central and 
peripheral fatigue due to increased heat storage at the brain and 
muscle levels, along with other physiological mechanisms (Ross et al., 
2016). As an individual's metabolic rate increases in hot environments, 
blood pH level may become more acidic and cause muscle fatigue from 
increased muscle glycogen degradation, lactate accumulation, and 
elevated carbohydrate metabolism (Varghese et al., 2018). These changes 
have been shown to compromise performance.
    Numerous studies demonstrate the relationship between heat exposure 
and fatigue. In a cross-sectional survey of 256 occupational health and 
safety professionals in Australia, fatigue was the most reported 
incident in workers during higher temperatures (Varghese et al., 2020). 
Among two groups of 55 steel plant workers who completed a 
questionnaire assessing fatigue, the group of workers exposed to hotter 
environments (30-33.2 [deg]C (80-91.76 [deg]F) WBGT) were significantly 
more likely to report symptoms of fatigue in comparison to workers in 
cooler environments (25.4-28.7 [deg]C (77.7-83.6 [deg]F) WBGT) (Chen et 
al., 2003). This study highlights how fatigue symptoms increase with 
rising heat exposure levels (Chen et al., 2003).
    Moreover, in a review of 55 studies on workplace heat exposure, 
core temperature elevation and dehydration have been shown to have 
numerous negative behavioral effects including fatigue, lethargy, and 
impaired coordination, which may lead to injury (Xiang et al., 2014a). 
These 55 articles included ecological (22%), cross-sectional (64%), and 
cohort (5%) studies, as well as epidemiological experiments (9%). From 
one study included in the review, 42% of construction workers surveyed 
reported it was ``easy to get fatigued'' while working in the summer 
(Inaba and Mirbod, 2007). In another review of heat stress risks in the 
construction industry, Rowlinson et al. (2014) also discussed the 
association of high temperatures and

[[Page 70730]]

level of fatigue, which has been considered one of the critical factors 
leading to construction accidents (Garrett and Teizer, 2009; Chan, 
2011). In a case study of 15 workers who experienced fatigue-related 
accidents, fatigue was shown to trigger other safety risks, such as not 
following proper safety procedures or becoming distracted, which can 
induce injury (Chan, 2011).
II. Impaired Postural Stability and Balance
    Heat exposure has also been shown to impair postural stability and 
balance as increases in metabolic heat can impact workers' gross motor 
capacity (i.e., the ability to move the body with appropriate 
sequencing and timing to perform bodily movements with refined 
control), including postural balance. As individuals become dehydrated, 
they may experience negative neuromuscular effects. Distefano et al. 
(2013) demonstrated the detrimental impact of dehydration during task 
performance in hot conditions, where subjects experienced decreased 
neuromuscular control as characterized by poorer postural stability. 
The authors found that neuromuscular control was impaired while 
participants were hypohydrated (defined as uncompensated loss of body 
water) and hyperthermic. Additionally, when an individual is 
experiencing high-intensity exertion in hot environments and is already 
dehydrated, this can result in further dilution of blood sodium. When 
blood sodium is diluted, water may be forced from the extracellular 
compartment into the intracellular compartment, which could lead to 
pulmonary congestion, brain swelling, and heat stroke (Distefano et 
al., 2013). At this stage, neurons begin degenerating in the cerebellum 
and cerebral cortex, and this process coupled with the rise in body 
temperature, impairs central nervous system functionality (Sawka et 
al., 2011; Nybo, 2007; Distefano et al., 2013).
    Research also indicates that performing exertional activities in a 
hot environment may impair balance. To better understand lower 
extremity biomechanics, Distefano et al. (2013) used an assessment tool 
to measure gross movement errors, such as medial knee displacement, hip 
or knee rotation, and limited sagittal plane (front to back) motion. 
The authors found that after performing the exercise protocol, 
participants demonstrated poorer movement technique when they were 
hypohydrated in a hot environment compared with when they were 
hypohydrated in a temperate environment or in a hot environment but 
euhydrated (state of optimal total body water content) (Distefano et 
al., 2013). These findings suggest that working in hot temperatures 
while dehydrated may increase risk for injury due to impaired balance 
(Distefano et al., 2013).
III. Impaired Performance in Accuracy, Speed, and Reaction Time
    The compromising effects of heat strain on psychomotor function 
have long been established, but the level of performance deterioration 
is dependent on the severity of heat strain and the complexity of the 
task (Taylor et al., 2016; Hancock, 1986; Ramsey, 1995; Pilcher et al., 
2002; Hancock and Vasmatzidis, 2003). Some research has found that when 
high skin and core temperatures increase cardiovascular strain, heat 
exposure results in faster reaction times where individuals respond 
more quickly, but less accurately when in the heat (Simmons et al., 
2008). Other research, such as Mazloumi et al. (2014), found that heat 
stress conditions impair selective attention (the ability to select and 
focus on a particular task while simultaneously ignoring other stimuli) 
and reaction time. In their study of 70 workers in Iran, where half of 
the workers experienced heat stress and half worked in air-
conditioning, the authors found impaired psychomotor function among the 
exposed workers indicated through an increase in the duration of a task 
and response time as well as an increase in the number of errors 
(Mazloumi et al., 2014).
    Additional studies examine the impacts of high skin and core 
temperatures on psychomotor function contributing to more mistakes 
(Allan and Gibson, 1979; Gibson and Allan, 1979; Gibson et al., 1980). 
In one study of foundry workers, response time, reaction time, and 
number of errors were reported to be adversely affected when workers 
were exposed to WBGTs of 31-35 [deg]C (87.8-95 [deg]F) compared to 
unexposed workers in a WBGT of 17 [deg]C (62.6 [deg]F) (Mazlomi et al., 
2017). A meta-analysis review of 23 studies supports these conclusions, 
finding that under hot conditions, performance on mathematical-related 
tasks and reaction time tasks can be negatively impacted at 32.2 [deg]C 
(89.9 [deg]F) with a roughly 15% average decrement in performance 
(Pilcher et al., 2002).
    Pyschomotor performance is an important factor when considering job 
tasks that require precision and concentration to prevent injuries. In 
a study observing steel plant workers, it was found that electrical arc 
melting workers who were exposed to hotter environments (30-33.2 [deg]C 
WBGT) experienced a significant decrease in their attention span and 
slower response time compared to the continuous cast workers, who 
worked in cooler environments (25.4-28.7 [deg]C WBGT) (Chen et al., 
2003). A decline in psychomotor function could also negatively affect 
speed of response, reasoning ability, associative learning, mental 
alertness, and visual perception, which has been reported as a key 
cause of fatal accidents (Rowlinson et al., 2014).
B. Impaired Mental Performance
    The effects of heat exposure on mental performance can also play a 
significant role in increasing workplace accidents and injuries and 
compromise workplace safety. Heat exposure can result in impaired 
cognition or cognitive performance; impaired visual motor tracking; and 
impaired decision-making or judgment, which can lead to unsafe 
behaviors (like the removal of required PPE). Each of these are 
discussed in turn below.
I. Impaired Cognition or Cognitive Performance
    Declines in cognitive function from heat are correlated with an 
elevated risk of injury. Evidence indicates a statistically significant 
increase in unsafe behaviors above 23 [deg]C WBGT and an increased risk 
of accidents (Ramsey et al., 1983). When an individual experiences 
hyperthermia, even if it is mild and only occurring for a short period, 
the central nervous system is vulnerable to damage (Hancock and 
Vasmatzidis, 2003). This can acutely affect memory, attention, and 
ability to process information (Walter and Carraretto, 2016). When 
hyperthermia triggers cerebral damage, these cerebral injuries can be 
characterized into three broad areas. The first area includes cellular 
effects (where cells are damaged as temperatures continue to rise and 
normal cell function is disrupted and cell replication is no longer 
possible). The second area includes local effects (like inflammatory 
changes and vascular damage), and the third area includes systemic 
changes (like changes in cerebral blood flow (Walter and Carraretto, 
2016). These negative effects are typically seen when core body 
temperatures reach 40 [deg]C (104 [deg]F), although some changes can 
begin at temperatures of 38 [deg]C (100.4 [deg]F) (Walter and 
Carraretto, 2016). These physiological changes also negatively impact 
cognitive performance.
    Heat exposure has been shown to affect cognitive performance

[[Page 70731]]

differentially, based on type of cognitive task (Yeoman et al., 2022). 
The more complex a task, especially if it requires motor accuracy, the 
more likely an individual's cognitive ability to perform the task will 
decline because of heat stress (Hancock and Vasmatzidis, 2003). Some 
research indicates a decrease in cognitive performance for tasks 
requiring more perceptual motor skills will be observed in the 30-33 
[deg]C (80-91.4 [deg]F) range, well before the physiological system 
reaches its tolerance limit (Ramsey and Kwon, 1992; Hancock and 
Vasmatzidis, 2003; Piil et al., 2017). Ramsey and Kwon (1992) have 
summarized over 150 studies looking at task exposure time and task type 
and found statistically significant performance decrements at the 30-33 
[deg]C (80-91.4 [deg]F) range. The decrements at this range occurred 
regardless of duration of exposure (from short exposures under 30 
minutes and longer exposures up to 8 hours) (Ramsey and Kwon, 1992). 
Furthermore, in a case study of nine male volunteers, results indicate 
that highly motivated subjects were strongly affected by heat load 
within the first two hours of exposure, and that these subjects' 
performance was significantly impaired when assigned complex tasks 
requiring a significant amount of reasoning and judgment (Epstein et 
al., 1980). The authors found that performance began to decrease when 
workers were exposed to temperatures above 27 [deg]C (80.6 [deg]F).
    Moreover, in a review of fifteen laboratory experiments assessing 
the effects of high ambient temperature on mental performance, one 
study found that mental performance declines were statistically 
significant at exposure durations of four consecutive hours in 87 
[deg]F (30.55 [deg]C) temperatures (Wing, 1965). Similarly, in a study 
of the effects of hot-humid and hot-dry environments on mental 
functioning, 25 participants were exposed to a variety of temperatures 
in humid and dry conditions, while performing physical exercises with 
bouts of rest, to assess mental alertness, associative learning, 
reasoning ability and dual-performance efficiency (Sharma et al., 
1983). The authors found that all the psychological functions tested 
were adversely affected under heat stress, and that a significant drop 
in various psychological functions was seen at temperatures of 32.2 
[deg]C (89.9 [deg]F) and 33.3 [deg]C (91.9 [deg]F) in hot-humid and 
hot-dry conditions, respectively. Moreover, the authors suggest that, 
for heat-acclimatized subjects who continuously work for four hours, 
that the temperature should not exceed 31.1 [deg]C (87.9 [deg]F) in hot 
and humid conditions, and 32.2 [deg]C (89.9 [deg]F) for workers in hot 
desert conditions (Sharma et al., 1983).
II. Impaired Visual-Motor Tracking
    Hyperthermia and dehydration, a common symptom of heat exposure, 
have been found to impair visual-motor tracking (i.e., the eyes' 
ability to focus on and follow an object), increasing the risk of 
workplace injury. In a review of studies on hydration and cognition, 
the authors indicate that a 2% or more loss of body weight due to 
dehydration from heat and exercise can result in significant reduction 
in visual-motor tracking (Lieberman, 2007). In an experimental study 
assessing performance in complex motor tasks in hyperthermic humans 
(Piil et al., 2017), the authors found that visual-motor tracking 
performance was reduced following exercise-induced hyperthermia. 
Participants were exposed to hot (40 [deg]C (104 [deg]F)) and control 
(20 [deg]C (68 [deg]F)) conditions. At baseline, and after exercise, 
participants completed simple and complex motor tasks, which included 
visual tracking assessment. The authors concluded that visual-motor 
tracking is impaired by hyperthermia, and especially so when multiple 
tasks are combined (Piil et al., 2017).
III. Impaired Decision-Making or Judgment
    Heat exposure has been found to affect decision-making or judgment 
amongst workers, increasing the risk of injury. In a review of 
ecological, cross-sectional, and cohort studies, as well as 
epidemiological experiments, Xiang, et al. indicate that core 
temperature elevation and dehydration impair judgment and concentration 
(Xiang, et al., 2014a). In a study analyzing over 17,000 observations 
of unsafe behavioral acts (e.g. mishandling tools, equipment, or 
materials) in two industrial facilities with varying temperature 
conditions, authors found that unsafe behavioral acts decreased within 
the zone of preferred temperature (approximately 17 [deg]C (62.6 
[deg]F) to 23 [deg]C (73.4 [deg]F), WBGT) and increased outside of this 
zone (when the temperature was equal to or less than 17 [deg]C WBGT or 
equal to or greater than 23 [deg]C WBGT) (Ramsey et al., 1983). This 
study indicates that the risk of unsafe behavioral acts may increase 
when the temperature increases.
C. Other Factors Contributing to Heat-Related Injury
    In addition to psychomotor and mental impairments that can result 
from heat exposure, other mechanisms may also contribute to heat-
related injuries. The purpose of this section is to summarize some 
additional factors that may exacerbate the risk of workplace heat-
related injuries and to provide information to better inform workers 
and employers about those hazards.
    PPE is another factor that plays a role in increasing 
susceptibility to a heat-related injury given that some PPE insolates 
the body and reduces evaporative cooling capacity. For instance, 
research among firefighters finds that a self-contained breathing 
apparatus can lead to heat buildup and can impact postural stability 
and balance (Hur et al., 2015; Hur et al., 2013; Games et al., 2020; 
Mani et al., 2013; Ross, 2016). Other examples of PPE that may result 
in heat stress, and therefore increase the risk of heat-related 
injuries, include reflective vests that are made of water impermeable 
material that block effective heat dissipation and safety helmets with 
no ventilation that can raise the temperature inside the helmet. In one 
case, the air temperature inside a worker's helmet (57 [deg]C (134.6 
[deg]F)) was measured to be over 20 [deg]C hotter than the 
environmental temperature (33 [deg]C (91.4 [deg]F)) they were working 
in (Rowlinson et al., 2014). The authors found that workers will often 
remove helmets in these situations to alleviate heat stress, exposing 
them to other workplace hazards (e.g., falling objects) (Rowlinson et 
al., 2014). Other research by Karthick et al. (2023) found that in hot 
weather conditions, physical health challenges, specifically major 
accidents at the job site, minor injuries, physical fatigue, excessive 
sweating, and dermatological problems were found to be significant 
based on a workers' clothing comfort. The authors highlighted how PPE 
can make workers feel uncomfortable, and when combined with extremely 
hot weather, it creates fatigue which may increase the number of 
workplace injuries and accidents (Karthick et al., 2023).
    There is also evidence indicating heat exposure can contribute to 
impaired vision, which may lead to workplace injuries. For example, 
fogged safety glasses or sweat in eyes due to heat exposure can reduce 
workers' visibility, creating additional hazards and increasing risk of 
injury (NIOSH, 2016). Individual case studies also report issues with 
protective eyewear in hot temperatures, noting the uncomfortable 
feeling of the eyewear under heat and in sunlight as well as difficulty 
seeing through the glasses (Choudhry and Fang, 2008). In a survey 
conducted among occupational health and safety professionals in 
Australia, one of the most frequently cited causes of heat-

[[Page 70732]]

related injuries was from ``impaired vision due to fogged safety 
glasses (39%)'' (Varghese et al., 2020). Injuries resulting from 
impaired vision may include manual handling (musculoskeletal injuries), 
joint/ligament injuries, hand injuries, wounds or lacerations, burns, 
head or neck injuries, motor vehicle accidents, eye injuries, or 
fractures (Varghese et al., 2020).
    When exposed to heat, workers may also experience impaired 
dexterity (or fine motor skills) leading to workplace injuries. For 
example, sweaty palms and hands due to heat exposure can reduce 
workers' ability to handle tools or other work-related materials, 
increasing the risk of injury. Occupational health and safety 
professionals have reported losing control of tools as one of the most 
common causes for heat-related injuries (Varghese et al., 2020). 
Researchers have also found sweaty palms to increase the risk of 
workplace injuries (Shulte et al., 2016).
IV. Summary
    The scientific and mechanistic data and association studies on 
heat-related injuries summarized in this section demonstrate that heat-
related injuries are a recognized health effect of occupational heat 
exposure. While the types of heat-related injuries can be broad, the 
scientific community recognizes that heat exposure can diminish the 
body's senses through various mechanisms like impaired psychomotor 
performance (e.g., fatigue, impaired balance, or impaired dexterity), 
and impaired mental performance (e.g., impaired cognition or vision) 
which can result in various types of injuries. The best available 
evidence demonstrates that heat-related injuries can have serious 
adverse effects on worker safety and health.

Q. Requests for Comments

    OSHA requests information and comments on the following question 
and requests that stakeholders provide any relevant data, information, 
or additional studies (or citations) supporting their view, and explain 
the reasoning for including such studies:
     Has OSHA adequately identified and documented the studies 
and other information relevant to its conclusions regarding heat-
related health effects, and are there additional studies OSHA should 
consider?

V. Risk Assessment

A. Risk Assessment

I. Introduction
    In this risk assessment, OSHA relied on surveillance data of 
occupational heat-related fatalities and non-fatal injuries and 
illnesses reported by the Bureau of Labor Statistics (BLS). 
Additionally, OSHA relied on annual incidence estimates derived from 
State workers' compensation systems and hospital discharge datasets. 
These estimates were calculated and reported in a variety of sources, 
such as reports from State health departments, as well as the peer-
reviewed scientific literature. OSHA has preliminarily concluded that 
inclusion criteria for HRIs in these data sources (days away from work, 
workers' compensation claim, emergency department visit, or inpatient 
hospitalization) demonstrate that the HRIs are a material impairment of 
health, thus making these data sources relevant to OSHA's determination 
of significant risk.
    OSHA has previously relied on such injury, illness, and death data 
to demonstrate the extent of risk (see, e.g., Fall Protection, 81 FR 
82494 (2016); Working Conditions in Shipyards, 76 FR 24576 (2011); 
Permit-Required Confined Spaces, 58 FR 4462, 4465 (1993) (finding 
significant risk based on available accident data showing that confined 
space hazards had caused deaths and injuries); Hazard Communication, 48 
FR 53280, 53284-85, 53321 (1983) (finding significant risk of harm from 
inadequate chemical hazard communication based on BLS chemical source 
injury and illness data)).
    Estimating annual incidence among heat-exposed workers (i.e., the 
number of annual work-related HRIs divided by the number of heat-
exposed workers) requires being able to accurately estimate the number 
of exposed workers and using that number in the denominator. 
Unfortunately, there is no published estimate for the number of U.S. 
workers exposed to hazardous heat on the job and the majority of the 
incidence estimates that OSHA identified used a denominator that would 
include both exposed and unexposed workers. This use of a larger 
denominator has the effect of diluting the resulting annual incidence 
estimates. For instance, BLS estimates and reports annual incidence of 
injuries and illnesses involving days away from work that were the 
result of ``exposure to environmental heat,'' but in their calculation, 
BLS captures the broader U.S. workforce in the denominator, which 
includes a large number of unexposed workers (e.g., office workers in 
climate-controlled buildings).
    Some of the annual incidence estimates that OSHA identified, such 
as those based on workers' compensation claims in California and 
Washington State, were stratified by sector, industry, or occupation. 
OSHA considers these incidence estimates to be helpful in getting to a 
more accurate estimate of risk among heat-exposed workers, specifically 
the sectors, industries, and occupations where exposure to hazardous 
heat on the job is more common. Furthermore, OSHA identified incidence 
estimates from cohort data in which the entire cohort was presumed to 
be exposed to hazardous heat on the job. These estimates are much 
higher than the estimates based on surveillance data. One potential 
reason for this difference is that the denominator used in the cohort 
studies contains much less unexposed worker-time.
    In the following sections (V.A.II., and V.A.III.), OSHA has 
summarized the best available incidence data that the agency 
identified. Given the limitations with these data, OSHA relied on this 
incidence data as a range of possible incidence estimates with the 
assumption that many of these estimates represent a lower bound and 
that the true incidence is likely higher.
II. Reported Annual Incidence of Nonfatal Occupational Heat-Related 
Injuries and Illnesses
A. BLS Survey of Occupational Injuries and Illnesses
    The BLS Survey of Occupational Injuries and Illnesses (SOII) is the 
primary nationwide source of surveillance data for nonfatal 
occupational injuries and illnesses. The scope includes both private 
and public (State and local government) sector employees, but excludes 
the self-employed, workers on farms with 10 or fewer employees, private 
household workers, volunteers, and Federal Government employees. The 
data are derived from a two-stage sampling process, during which a 
sample of employers are surveyed and report to BLS the number of 
injuries and illnesses occurring at their workplace. To reduce the 
reporting burden on employers, BLS only requires detailed case 
information on a sample of the injuries and illnesses that occurred at 
each establishment. BLS uses these survey responses to estimate the 
counts and incidence for nonfatal injuries and illnesses across all 
workplaces. In estimating annual incidence, BLS uses a denominator of 
full-time equivalent (FTE) workers,

[[Page 70733]]

which is based on 2,000 hours worked per year (i.e., 40 hours per week 
over 50 weeks). Relevant Occupational Injury and Illness Classification 
System (OIICS) v2.01 event and nature codes for this proposed standard 
include ``Exposure to environmental heat'' (event code-531) and 
``Effects of heat and light'' (nature codes beginning in 172-). Codes 
beginning with 172- include heat stroke and heat exhaustion (among 
other outcomes) but exclude sunburn and loss of consciousness without 
reference to heat. For more information about OIICS codes generally, 
see Section IV., Health Effects.
    Between 2011 and 2020, there were an estimated 33,890 work-related 
injuries and illnesses that involved days away from work that were 
coded with event code 531, for an annual average of 3,389 such injuries 
and illnesses during this period (BLS 2023b). In 2023, BLS reported 
biennial rather than annual estimates for work-related injuries and 
illnesses that involved days away from work (as well as for the first 
time reporting an estimate of injuries and illnesses involving job 
restriction or job transfer). The biennial estimate for 2021-2022 for 
heat-related cases meeting either of these criteria was 6,550 (5,560 
cases involved days away from work; 990 cases involved job transfer or 
restriction) (BLS 2023g). The estimated annual heat-related injury and 
illness incidence (for cases involving days away from work) calculated 
by BLS for all workers covered by SOII from 2011-2020 varied by year 
but ranged from 2.0/100,000 workers to 4.0/100,000 workers. The average 
estimated annual incidence for the entire time period was 3.0/100,000 
workers. However, as stated above, OSHA considers these incidence 
estimates to be underestimated for heat-exposed workers because BLS 
calculates the incidence rate for the entire U.S. workforce covered by 
SOII. Therefore, they are including workers who are not exposed to 
hazardous heat. In subsectors and industries where OSHA expects a 
greater proportion of workers to be exposed to hazardous heat, the 
incidence rate estimates are much higher. For instance, according to 
unpublished data from BLS SOII for the period 2011-2020, the crop 
production subsector (NAICS code 111) had an annual average incidence 
of 14.2/100,000 workers, and the specialty trade contractors subsector 
(NAICS code 238) had an annual average of 9.3/100,000 workers. This was 
also true of subsectors with primarily indoor workers where OSHA 
expects a greater proportion of those workers to be exposed to 
hazardous heat, including the primary metal manufacturing subsector 
(NAICS code 331), which had an annual average incidence of 13.1/100,000 
workers for the period 2011-2020.
B. Workers' Compensation Claims
    Workers' compensation claims are an alternative way to quantify 
occupational injuries and illnesses, particularly those that involve 
outpatient medical treatment, inpatient hospitalization, intensive 
care, and/or lost workdays. OSHA identified five papers and a report 
from Wisconsin that have evaluated State workers' compensation data and 
calculated statewide incidence for heat-related injuries and illnesses.
I. Washington State
    The earliest of these, a paper by Bonauto et al., in 2007, 
evaluated workers' compensation claims submitted to and accepted by the 
Washington State Fund between 1995 and 2005 (Bonauto et al., 2007). The 
State Fund is the sole provider of workers' compensation insurance to 
Washington employers unless they are self-insured or fall under an 
alternative system (e.g., Federal employees) and it covers 
approximately two-thirds of the State's workers. Certain workers are 
exempt from mandatory coverage, such as self-employed and household 
workers. The authors identified heat-related cases using the American 
National Standards Institute (ANSI) Z16.2 codes \2\ submitted in the 
claims by workers or their physicians, the ICD-9 codes submitted on 
bills from healthcare providers and hospitals, and a physician review 
of cases that included relevant Z16.2 or ICD-9 codes. The researchers 
used all ICD-9 codes beginning in 992 (``Effects of heat and light,'' 
specifically 992.0-992.9) and the ANSI Z16.2 type code 151 (``Contact 
with general heat--atmosphere or environment''). ICD-9 codes were not 
available for claims from the self-insured, so the authors restricted 
the analysis to State Fund claims only. They also excluded claims in 
which the employer's physical location was outside of Washington 
(n=12).
---------------------------------------------------------------------------

    \2\ The American National Standards Institute, or ANSI, created 
a standard for occupational health and safety metrics in 1962 
(revised in 1969) referred to as ANSI Z16. The first version of 
OIICS was based on the ANSI coding scheme. ANSI revised the Z16 
standard in 1995 and adopted the OIICS scheme in that revision.
---------------------------------------------------------------------------

    Over the 11-year study period, 480 accepted claims met the authors' 
inclusion criteria after physician review, in which they identified and 
removed cases where the recorded illness had been miscoded, contained 
incorrect data, or represented a burn. Most of the 480 claims (n=442; 
92.1%) were medical-only claims, meaning the State Fund only paid for 
the medical bills and did not compensate the worker otherwise (e.g., 
wage replacement, disability benefits). The claims included the 
employer's NAICS code, which the authors used to stratify cases by 
industry sectors and industries. Employers covered under the Washington 
State Fund are required to report hours worked by their employees every 
quarter (i.e., three-month increments), which the authors used to 
estimate denominators for rates assuming 2,000 work hours is 1 FTE. 
This means the authors could calculate rates for certain portions of 
the year rather than the whole year without needing to divide by the 
total number of annual workers (i.e., they could adjust for hours 
worked only during the specified portion). The employment reporting by 
quarter also allowed for the authors to estimate claim rates for the 
third quarter only (July, August, and September), which corresponded to 
the time of year with the ``greatest level of exposure to elevated 
environmental temperatures'' (Bonauto et al., 2007, p. 5).
    The authors reported an average annual claim rate (which can be 
thought of similarly to an injury or illness incidence rate) of 3.1 
claims/100,000 FTE for the overall workforce covered by the State Fund 
during the study period, with annual rates ranging from 1.9 to 5.1/
100,000 FTE. They reported a corresponding average third-quarter claim 
rate of 8.6 claims/100,000 FTE for the overall workforce covered by the 
State Fund during the study period. In their paper, Bonauto et al. 
report annual and third-quarter rates for all sectors and industries 
that had more than five claims during the study period. The sectors (2-
digit NAICS) with the highest annual average claim rates were:
    1. Construction (12.1/100,000 FTE),
    2. Public administration (12.0/100,000 FTE),
    3. Agriculture, forestry, fishing, and hunting (5.2/100,000 FTE),
    4. Administrative and support and waste management and remediation 
services (3.9/100,000 FTE), and
    5. Transportation and warehousing (3.5/100,000 FTE).
    The corresponding average third-quarter claim rates for these 
sectors were more than double the annual averages: 33.8/100,000 FTE, 
31.2/100,000 FTE, 12.6/100,000 FTE, 9.9/100,000 FTE, and 10.6/100,000 
FTE, respectively. This pattern was also true

[[Page 70734]]

for some sectors with a majority of indoor claims. For example, 
Manufacturing (3.0/100,000 FTE vs. 7.6/100,000 FTE) and Accommodation 
and food services (1.7/100,000 FTE vs. 5.1/100,000 FTE).
    The industries (6-digit NAICS) with the highest annual average 
claim rates were:
    1. Fire protection (80.8/100,000 FTE),
    2. Roofing construction (59.0/100,000 FTE),
    3. Highway, street and bridge construction (44.8/100,000 FTE),
    4. Site preparation construction (35.9/100,000 FTE) (tie), and
    5. Poured concrete foundation and structural construction (35.9/
100,000 FTE) (tie).
    Similar to the pattern observed among sectors, the corresponding 
third-quarter claim rates for the top 5 industries were more than 
double the annual averages, except for fire protection--158.8/100,000 
FTE, 161.2/100,000, 105.6/100,000 FTE, 106.5/100,000 FTE, and 102.6/
100,000 FTE, respectively. This was also true for restaurants: limited 
service restaurants (2.4/100,000 FTE vs. 6.0/100,000 FTE) and full 
service restaurants (1.6/100,000 FTE vs. 5.3/100,000 FTE). These 
industries have few to no outdoor claims, indicating that even some 
industries that involve primarily indoor work are at higher risk in the 
summer months.
    A follow-up paper to Bonauto et al., 2007, published in 2014, 
examined heat-related illnesses among workers in Washington State in 
certain agriculture and forestry subsectors between 1995 and 2009 
(Spector et al., 2014). The State changed their injury and illness 
codes from ANSI to OIICS in July 2005, so for this paper, the 
researchers used a combination of ANSI (prior to July 2005), OIICS 
(beginning in July 2005), and ICD-9 codes to identify potential heat-
related claims and then reviewed each claim to ensure it was heat-
related. These authors used additional ICD-9 codes that were not 
included in the 2007 paper, specifically: prickly heat (705.1), 
hyperosmolality and/or hypernatremia (276.0), volume depletion (276.5 
and 276.50), dehydration (276.51), hypovolemia (276.52), and acute 
renal failure (584 and 584.9). The authors identified 84 accepted 
claims meeting their eligibility criteria, the majority of which (n=76; 
90%) were medical only claims. Of the 84 claims, 61 (73%) met the 
diagnostic code criteria used in the 2007 paper (ICD-9 codes beginning 
in 992). The average annual claim rate for the agriculture and forestry 
subsectors the authors examined over the 15-year period was 7.0/100,000 
FTE and the average third-quarter (July-September) claim rate was 15.7/
100,000 FTE. The majority of claims (61%) were among crop production 
and support workers (NAICS 111 or 1151).
    A second follow-up paper to Bonauto et al., 2007, was published in 
2020 and included all Washington State Fund-covered workers over a more 
recent 12-year period, 2006 to 2017 (Hesketh et al., 2020). The authors 
used similar methods, except for different screening criteria for 
ascertaining cases prior to investigators reviewing each case. To 
identify potential heat-related claims, they used OIICS v1.01 event/
exposure code 321, OIICS nature code 072*, OIICS source codes 9362 and 
9392 (Sun), and the ICD-9 codes used in Spector et al., 2014. (Note 
that these OIICS codes are v1.01 OIICS, which was the coding scheme 
used from 1992-2010. BLS updated the coding scheme in 2010, which first 
applied to 2011 data.) The State adopted ICD-10 coding in October 2015, 
so the following ICD-10 codes were used for claims after that date: 
E86* (Volume depletion), T67* (Effects of heat and light), T73.2* 
(Exhaustion due to exposure), W92* (Exposure to excessive heat of man-
made origin), X30* (Exposure to excessive natural heat), and Z57.6 
(Occupational exposure to extreme temperature). The researchers 
excluded claims in which service date for treatment of dehydration or 
kidney failure was not within one day of the illness date or claims in 
which dehydration or kidney failure were the only identifiers flagged, 
as they noted that these cases often did not represent heat-related 
illnesses.
    The authors reported a total of 918 confirmed heat-related claims, 
of which 654 (71%) were accepted claims. Of the accepted claims, 595 
(91%) were medical-only claims. Using only accepted claims, they 
estimated an average annual claim rate of 3.2 claims/100,000 FTE for 
the overall workforce covered by the State Fund during the study period 
(Communication with David Bonauto and June Spector, June 2024). Similar 
to Bonauto et al., 2007, the authors reported claim rates for all 
sectors and industries with more than 11 claims. The sectors (2-digit 
NAICS) with the highest annual average accepted claim rates were:
    1. Agriculture, forestry, fishing, and hunting (13.0/100,000 FTE),
    2. Construction (10.8/100,000 FTE),
    3. Public administration (10.3/100,000 FTE),
    4. Administrative and support and waste management and remediation 
services (4.6/100,000 FTE), and
    5. Transportation and Warehousing (3.8/100,000 FTE).
    The average third-quarter (July-September) claim rates for some 
sectors were more than 10 times greater than the average annual rates. 
These third-quarter claim rates were also much higher than those 
calculated for 1995-2005 in Bonauto et al., 2007. The sectors with the 
highest average third-quarter accepted claim rates were:
    1. Public administration (131.3/100,000 FTE),
    2. Agriculture, forestry, fishing, and hunting (102.6/100,000 FTE),
    3. Construction (70.0/100,000 FTE),
    4. Administrative and support and waste management and remediation 
services (61.5/100,000 FTE), and
    5. Wholesale trade (44.9/100,000 FTE).
    The industries (6-digit NAICS) with the highest annual average 
accepted claims rates were:
    1. Farm labor contractors and crew leaders (77.3/100,000 FTE),
    2. Fire protection (60.0/100,000 FTE),
    3. Structural steel and precast concrete contractors (54.2/100,000 
FTE),
    4. Poured concrete foundation and structure contractors (31.6/
100,000 FTE), and
    5. Roofing contractors (29.0/100,000 FTE).
    The ratio between third-quarter rates and annual rates for all 
industries reported in table 3 of the paper ranged from 2.5-13.7, with 
the highest average third-quarter accepted claim rates in the following 
industries:
    1. Farm labor contractors and crew leaders (600.9/100,000 FTE),
    2. Fire protection (394.6/100,000 FTE),
    3. Administration of conservation programs (282.7/100,000 FTE),
    4. Site preparation contractors (232.1/100,000 FTE), and
    5. Poured concrete foundation and structure contractors (172.3/
100,000 FTE).
II. California
    A group of researchers conducted a similar analysis for the State 
of California, using data from the California Workers' Compensation 
Information System (WCIS) between 2000 and 2017 (Heinzerling et al., 
2020). Virtually all California employees are required to be covered by 
workers' compensation; voluntary, non-compensated workers, owners, and 
workers covered under separate programs are excluded. The WCIS contains 
all accepted and rejected workers' compensation claims in the State 
since 2000 that required medical treatment beyond first aid or more 
than

[[Page 70735]]

one day of lost work time. The investigators identified heat-related 
claims in the system using WCIS-specific nature of injury and cause of 
injury codes (e.g., ``temperature extremes''), heat-related illness 
keywords (e.g., ``heat stroke''), and certain ICD-9 (992.0-992.9 and 
E900.0-E900.9) and ICD-10 (T67.0-T67.9, X30, and W92) codes. They also 
manually reviewed all claims that met only the ICD code identification 
criteria to ensure the claims were heat-related, as some of the codes 
they used to identify claims were not specific to heat-related illness 
or injury. In WCIS, the employer's industry is coded using NAICS codes 
classified by the claims adjusters. The authors converted the NAICS 
codes into the appropriate 2002 census industry codes using the NIOSH 
Industry and Occupation Computerized Coding System (NIOCCS). This was 
necessary to obtain the corresponding employment denominator estimates 
from the NIOSH Employed Labor Force Tool, which relies on data from the 
Current Population Survey (CPS), a Census Bureau survey conducted for 
BLS. The CPS data provide estimates of all employed and non-
institutionalized civilian workers over the age of 15. To account for 
changes in coding schemes implemented in 2002, the investigators 
extrapolated 2002-2017 data to estimate denominators for 2000 and 2001.
    The authors excluded claims for workers below 16 years of age 
(n=104 claims) and institutionalized workers (n=455 claims), as these 
workers are excluded from CPS data. They reported a final estimate of 
15,996 claims meeting their inclusion criteria, corresponding to an 
overall annual claims rate of 6.0/100,000 workers. Industry and 
occupation codes were available for 86% and 74% of the included claims, 
respectively. The authors reported claim rates for all sectors, but the 
sectors with the highest annual claim rates were:
    1. Agriculture, forestry, fishing, and hunting (38.6/100,000 
workers; 95% CI: 26.9, 40.4),
    2. Public administration (35.3/100,000 workers; 95% CI: 34.3, 
36.3),
    3. Mining (21.3/100,000 workers; 95% CI: 17.6, 25.7),
    4. Utilities (11.4/100,000 workers; 95% CI: 10.1, 12.8), and
    5. Administrative and support and waste management (8.8/100,000 
workers; 95% CI: 8.3, 9.3).
    The major occupational groups with the highest annual claim rates 
were:
    1. Protective services (56.7/100,000 workers; 95% CI: 54.9, 58.7),
    2. Farming, fishing, and forestry (35.9/100,000 workers; 95% CI: 
34.1, 37.9),
    3. Material moving (12.3/100,000 workers; 95% CI: 11.5, 13.1),
    4. Construction and extraction (8.9/100,000 workers; 95% CI: 8.4, 
9.4), and
    5. Building and grounds cleaning and maintenance (6.0/100,000 
workers; 95% CI: 5.6, 6.5).
III. Texas
    Another study examined workers' compensation claims in an unnamed, 
mid-sized Texas city before and after an intervention among a cohort of 
604 municipal workers and calculated the incidence of HRI claims from 
2009 to 2017 (McCarthy et al., 2019). The municipal departments 
included in the study were picked because the job descriptions for 
workers within each included work in hot environments with moderate and 
heavy physical activity. These departments were Streets and Traffic, 
Parks and Recreation, Utilities, and Solid Waste. After removing 
worker-time contributed by administrative personnel who were not 
exposed to heat on the job, the remaining worker-time represented 329 
FTEs per year. Prior to the intervention in 2011, the heat-exposed 
workers experienced 17 total HRIs between 2009 and 2010. The authors 
reported an average annual rate of HRIs among the heat-exposed workers 
during this time of 25.5/1,000 FTEs (McCarthy et al., 2019, Figure 2). 
These estimates are much higher than other incidence estimates reported 
in this section, possibly because the denominator is solely comprised 
of heat-exposed workers. This explanation is supported by evidence of 
higher incidences reported in other cohort studies (e.g., approximately 
3 HRIs/1,000 National Guard troops involved in flood relief activities 
between July 5 and August 18, 1993, calculated from data in Dellinger 
et al., 1996). The results of the voluntary intervention are discussed 
in Section V.C., Risk Reduction.
IV. Wisconsin
    Finally, a report issued by the Wisconsin Occupational Health and 
Safety Surveillance Program in 2024 summarized an analysis of heat-
related workers' compensation claims in the State from 2010-2022 (Fall 
et al., 2024). The authors analyzed lost work time claims (under 
Wisconsin workers' compensation, there must be more than three days of 
lost work time to be compensable) reported by both insurance carriers 
and self-insured employers and reported rates by industry sector and 
industry subsector (rather than overall workforce rates). These do not 
include medical-only claims, which were the majority of HRI claims 
reported in the Washington State Fund database. The authors reported 
cumulative claim rates only. To convert cumulative rates to annual 
average rates, OSHA divided the reported rates by 13 (the number of 
years' worth of data reported). The sectors with the highest annual 
average claim rates were:
    1. Administrative and Support and Waste Management and Remediation 
Services (2.9/100,000 FTE),
    2. Public Administration (2.8/100,000 FTE),
    3. Wholesale Trade (1.9/100,000 FTE),
    4. Construction (1.4/100,000 FTE), and
    5. Transportation and Warehousing (1.1/100,000 FTE).
    The major occupational groups with the highest annual average 
claims rates were:
    1. Protective Service (4.1/100,000 FTE),
    2. Transportation and Material Moving (2.6/100,000 FTE),
    3. Production (1.6/100,000 FTE),
    4. Construction and Extraction (1.5/100,000 FTE), and
    5. Building and Grounds Cleaning and Maintenance (1.5/100,000 FTE).
    Similarly, the minor occupational groups with the highest annual 
average claims rates were:
    1. Fire Fighting and Prevention (14.7/100,000 FTE),
    2. Material Moving Workers (3.3/100,000 FTE),
    3. Metal and Plastic Workers (2.8/100,000 FTE),
    4. Motor Vehicle Operations (2.2/100,000 FTE), and
    5. Assemblers and Fabricators (2.2/100,000 FTE).
C. Emergency Department (ED) Visits and Inpatient Hospitalizations
    Another way to quantify occupational injury and illnesses requiring 
medical treatment is to use data reported directly by hospitals to 
public health departments or national databases, such as the National 
Electronic Injury Surveillance System (NEISS). Data in NEISS are 
estimated from a nationally representative probability sample of 
hospitals across the country, which report data for every injury-
related ED visit. A paper from 2010 analyzed NEISS data for heat-
related emergency department visits from 2001-2004 (Sanchez et al., 
2010). The authors reported an annual average of 8,376 work-related ED 
visits for nonfatal heat injuries and illnesses. OSHA used annual 
average employment estimates from NIOSH's Employed Labor Force query 
system for 2001-2004 (both total workers and FTEs) to estimate a 
nationwide annual average rate of 6.1

[[Page 70736]]

visits/100,000 workers and 6.3 visits/100,000 FTEs from this study. 
More recent studies estimating the incidence of work-related ED visits 
and/or hospitalizations for HRIs within individual or multiple States 
are discussed below.
I. Southeast U.S.
    A group of public health researchers from nine States in the 
Southeast (Florida, Georgia, Kentucky, Louisiana, Mississippi, North 
Carolina, South Carolina, Tennessee, and Virginia) used hospital 
discharge data reported directly to State health departments to 
characterize rates of heat-related inpatient hospitalization and ED 
visits among workers from 2007--2011 (Harduar Morano et al., 2015). The 
researchers used ICD-9 codes to identify heat-related cases, 
specifically 992.0-992.9, E900.0, E900.1, and E900.9. To assess work-
relatedness, they determined whether the expected payer was workers' 
compensation or if a work-related external cause of injury code 
(sometimes referred to as E-codes) was noted by the physician (e.g., 
E000.0 Civilian activity done for income). They restricted cases only 
to those where the patient was at least 16 years old but included both 
State residents and non-residents in reported case counts. To calculate 
rates, the investigators used CPS data for estimating denominators, 
which were age-adjusted using direct standardization and population 
weights for the entire U.S. Non-residents were not included in the rate 
calculations. The authors noted that hospital discharge data weren't 
available for every year in every State and that the missing data were 
primarily for discharges following ED visits.
    Across the five-year study period, the authors identified 8,315 
occupational heat-related ED visits (7,664 of these among residents, or 
92%), which corresponded to an overall age-adjusted rate of 6.5 visits/
100,000 workers (95% confidence interval, CI = 6.4, 6.7). While they 
reported rates for each State (e.g., 4.8 visits/100,000 workers in 
Florida and 17.3 visits/100,000 workers in Louisiana), they cautioned 
against directly comparing between States given differences in the data 
collection methods, data availability, and use of work-related 
variables. They identified 1,051 occupational heat-related inpatient 
hospitalizations (930 among residents, or 88%), which corresponded to 
an overall age-adjusted rate of 0.61 hospitalizations/100,000 workers 
(95% CI = 0.58, 0.66). The average length of stay for State residents 
was 2.7 days, which was comparable to non-residents (2.4 days).
II. Florida
    The Florida Department of Health published a similar analysis in 
2011 using the same methods for the State of Florida for the years 
2005--2009 (Florida DOH, 2011). They identified 2,198 occupational 
heat-related hospitalizations and ED visits, which corresponded to an 
average overall age-adjusted annual rate of 3.7 cases/100,000 workers 
(95% CI = 1.9, 5.5) and a crude rate (no age adjustment) of 5.1/100,000 
workers (Communication with Laurel Harduar Morano, October 2023). The 
majority of these (89.4%) were ED visits. They identified 3 fatalities 
in this subset, which they noted corresponds to a case fatality rate of 
1.4 fatalities/1,000 cases. They reported a third-quarter (July, 
August, and September) rate of 3.2 cases/100,000 workers using a 
denominator of total number of workers, whereas using a denominator of 
FTEs instead produced a third-quarter rate of 13.0 cases/100,000 FTE 
(Communication with Laurel Harduar Morano, October 2023). A 2016 study 
conducted a more in-depth analysis of the statewide Florida 
hospitalization data and included data for three additional years 
(2010, 2011, and 2012) (Harduar Morano et al., 2016). The authors 
restricted the data to cases occurring in May-October of each year and 
identified a total of 2,979 work-related ED visits and 415 work-related 
hospitalizations between 2005-2012. Using total number of workers in 
the denominator (calculated from monthly CPS data), these corresponded 
to average annual age-adjusted rates of 8.5 ED visits/100,000 workers 
and 1.1 hospitalizations/100,000 workers.
III. Louisiana
    In March 2023, the Louisiana Department of Health published a 
report on heat-related illnesses in the State using ED and 
hospitalization data from 2010-2020 (Louisiana DOH 2023). The authors 
used workers' compensation as payer and work-related ICD codes to 
determine which cases were among workers. They reported an annual 
average of 320 work-related ED visits and 20 work-related 
hospitalizations for heat-related illness during this period. Using 
State employment data from CPS, the authors calculated an overall age-
adjusted rate of 15.1 work-related ED visits/100,000 workers and 0.9 
work-related hospitalizations/100,000 workers. In 2024, the Department 
of Health released a syndromic surveillance report on ED visits for 
HRIs between April 1 and October 31, 2023 (Louisiana DOH 2024). They 
identified 1,412 ED visits for HRIs among workers during this time 
period.
IV. Multiple States
    Since 2013 over 20 States have reported rates of heat-related ED 
visits among workers to the Council of State and Territorial 
Epidemiologists (CSTE), comprising the organization's Occupational 
Health Indicator #24 (see www.cste.org/page/ohindicatorstable). These 
data are compiled by the State health departments using workers' 
compensation as primary payer and external cause of injury codes to 
determine work-relatedness. Rates are calculated using CPS estimates of 
total employed persons by State. While multiple States report their 
annual rates to CSTE, the organization cautions against directly 
comparing these rates between States because ``workers' compensation 
eligibility criteria and availability of data from workers' 
compensation programs varies among states, prohibiting state-level data 
from being directly compared to other states or with national 
estimates.''
    Additionally, given that these data are not available for every 
State, they cannot be combined to produce an accurate national rate. 
The State-reported rates are currently available for 2013-2019. During 
this period, the annual rates for heat-related ED visits ranged from 
0.1 to 18.7 ED visits per 100,000 workers.
V. Maricopa County, Arizona
    Arizona is not one of the States to share their ED visit data to 
CSTE, but the most populated county in the State--Maricopa County--has 
published a Heat Morbidity Report in which they provide case counts for 
heat-related hospitalization discharges, including a breakdown of the 
``preceding activity type'' (determined by ICD activity E-codes) 
(Maricopa County Public Health Department, n.d.). Using the case counts 
reported under ``occupational'' activity type and yearly estimates of 
the average annual employment for Maricopa County provided by the BLS 
Quarterly Census of Employment and Wages, there was an average annual 
hospitalization rate among workers of 4.1 cases/100,000 workers (range: 
3.1-6.4/100,000) between 2010-2017. Primary payer of workers' 
compensation was not used to determine work-relatedness, which means 
some occupational cases not involving E-codes may have been missed. 
Given that for the majority of cases (77%-83% per year), the preceding 
activity was marked as ``unknown'', it's likely that some number of 
these were occupational in nature and just not listed as such. This

[[Page 70737]]

is supported by the fact that an ``Industrial Site'' was the place of 
injury for, on average, 8% of cases, which may also be an 
underestimate. It should be noted that the authors only used the 
following ICD-9/ICD-10 activity E-codes to determine work-relatedness: 
E011/Y93.C Activities involving computer technology and electronic 
devices; E012/Y93.D Activities involving arts and handcrafts; and E016/
Y93.H Activities involving exterior property and land maintenance, 
building and construction. To OSHA's knowledge, the authors did not use 
any other external cause of injury codes, such as E000.0 Civilian 
activity done for income, but it is not clear from the report if these 
E-codes were not available or were just not used.
D. Indirect Injuries
    As discussed in Section IV.P., Heat Related Injuries, one area of 
research has used the natural fluctuations in temperatures to conduct 
quasi-experimental studies examining the relationship between heat and 
workers' compensation claims for traumatic injuries (e.g., Spector et 
al., 2016; Calkins et al., 2019; Dillender 2021; Park et al., 2021). 
The findings of these papers suggest that there may be many workers' 
compensation claims that are heat-related but not coded as such. For 
instance, Park, Pankratz, and Behrer (2021) estimated that 
approximately 20,000 injuries per year in California between 2001-2018 
resulted from hotter temperatures (relative to ``optimal'' 
temperature). For comparison, for a similar time period (2000-2017), 
Heinzerling et al. (2020) only identified an average of 889 HRI 
workers' compensation claims per year in California (a 22-fold 
difference), suggesting that relying on workers' compensation claims 
coded as HRIs alone does not capture the higher incidence of injuries 
of other kinds where heat may have played a role. A research report 
from the Workers Compensation Research Institute expanded this type of 
analysis to 24 States, using a convenience sample of workers' 
compensation claims from May-October 2016-2021 (Negrusa et al., 2024). 
They found that the number of injuries increased 3.2-6.1% when the 
daily maximum temperature was 75 [deg]F or higher relative to a day 
with a daily maximum temperature of 65-70 [deg]F. This relationship was 
even more pronounced for the construction industry.
E. Worker Self-Reports
    Another source of incidence data is surveys of workers exposed to 
heat. Multiple papers describe the results of surveys of outdoor 
workers, typically agricultural workers, who are asked about heat-
related symptoms experienced over a week-long period while working in 
the summer months (Fleischer et al., 2013; Kearney et al., 2016; Mutic 
et al., 2018). Commonly reported symptoms in these studies include 
heavy sweating (38-66% of surveyed workers), headache (44-58%), muscle 
cramps (30-36%), dizziness (14-32%), weakness or fatigue (18%), and 
nausea or vomiting (9-17%). Notably, in two of these studies, multiple 
workers reported fainting on the job. A study in southern Georgia found 
that 4% of 405 farmworkers experienced fainting within the previous 
week, during which the heat index ranged from 100-108 [deg]F (Fleischer 
et al., 2013). Another study involved asking 281 farmworkers in North 
Carolina if they had ever worked in ``extreme heat.'' Of those 
answering ``yes'', 3% reported having ever fainted on the job 
(Mirabelli et al., 2010). When asked about symptoms over a single 
workday, a separate study found that 25% of workers reported cramps, 
22% headache, 10% dizziness, and 3% nausea (Smith et al., 2021).
F. Summary of Reported Annual Incidence of Nonfatal Occupational Heat-
Related Injuries and Illnesses
    OSHA identified multiple sources that have reported annual 
incidence estimates for nonfatal HRIs among workers. These studies and 
reports generally reported heat-related incidence across an entire 
workforce (either National or State), using the total workforce as the 
denominator. This would understate the risk to workers who are actually 
exposed to heat on the job since the denominator includes a large 
percentage of workers who are not exposed to heat (e.g., office 
workers). Evidence in support of this claim comes from studies showing 
higher incidence of HRI when populations are stratified by sector, 
industry, or occupation, as well as those reporting incidence that 
occurred only during the third quarter (July, August, and September). 
For instance, in Heinzerling et al., 2020, the authors report an 
overall annual incidence of 6.0/100,000 workers whereas they report an 
annual incidence of 38.6/100,000 workers for workers in the 
agriculture, forestry, fishing, and hunting sector (a greater than 6-
fold difference). OSHA considers these stratified estimates to be more 
accurate estimates of the ``true'' incidence of HRIs among heat-exposed 
workers.
    A summary of the annual incidence estimates for nonfatal 
occupational HRIs discussed above can be found in table V-1. In the 
same table, OSHA calculated the number of non-fatal HRIs that would be 
expected over a working lifetime (assuming a working lifetime is 45 
years long) based on those annual incidence estimates (i.e., the annual 
incidence multiplied by 45). These estimates represent the total number 
of HRIs that may be expected to occur in a cohort of 100,000 workers 
all of whom enter the workforce at the same time and all of whom work 
for 45 years. Estimates of HRI risk over a working lifetime based on 
annual incidence among entire working populations (National or State) 
range from 90-180/100,000 for HRIs requiring days away from work, 140-
270/100,000 for HRIs leading to a workers' compensation claim, and 4.5-
842/100,000 for HRIs leading to emergency department visits or 
inpatient hospitalizations. Like incidence estimates, these values 
understate the risk to workers who are actually exposed to heat on the 
job since the denominator includes a large percentage of workers who 
are not exposed to heat (e.g., office workers). However, when using 
incidence estimates specific to individual sectors, industries, or 
occupations, the HRI estimates over a working lifetime are much higher, 
ranging from 49.5-114,750/100,000 for HRIs leading to a workers' 
compensation claim.
III. Reported Occupational Heat-Related Fatalities
    The BLS Census of Fatal Occupational Injuries (CFOI), established 
in 1992, is the primary source of surveillance data on work-related 
fatalities, including fatalities due to environmental heat exposure, 
for the United States. The fatality data in CFOI come from diverse data 
sources to identify, verify, and describe work-related fatalities. In 
each case, at least two sources (e.g., death certificates, workers' 
compensation reports, media reports, and government agency 
administrative reports) and an average of four are used to validate 
that the fatality was work-related and to verify the event or exposure 
leading to death and the nature of injury or illness in each case, 
which are then classified with OIICS codes. Heat-related fatalities can 
be identified with an event code (``Exposure to environmental heat'') 
and/or a nature code (``Effects of heat and light'').
    According to BLS's CFOI, occupational heat exposure killed 1,042 
U.S. workers between 1992 and 2022 (BLS, 2024c). Between 2011 and 2022, 
BLS reports 479 worker deaths, an average of 40 fatalities per year 
during that time. During the latest three years

[[Page 70738]]

for which BLS reports data (2020-2022), there was an average of 45 
work-related deaths due to exposure to environmental heat per year. 
Multiple sources have relied on BLS surveillance data to estimate 
annual incidence rates of occupational heat-related fatalities.
    Gubernot et al. (2015) calculated overall fatality rates and 
fatality rates by industry sector using BLS CFOI data from 2000-2010 
(Gubernot et al., 2015). The authors focused on the three industry 
sectors with the highest rates in preliminary analyses: Agriculture, 
Forestry, Fishing and Hunting (NAICS code 11); Construction (NAICS code 
23); and Administrative and Support and Waste Management and 
Remediation Services (NAICS code 56). All other industry sectors were 
combined for comparison as a referent group. The authors used 
nationwide worker population data from the CPS to estimate fatality 
rates. The CPS data provide estimates of all employed and non-
institutionalized civilian workers over the age of 15.
    The authors identified 339 occupational heat-related deaths from 
2000-2010, after excluding volunteers and military personnel. They 
reported an average annual heat-related fatality rate of 0.022 
fatalities per 100,000 workers for the overall workforce.
    For the three industry sectors preliminarily identified as having 
the highest rates, the authors reported the following average annual 
fatality rates:
    1. Agriculture, forestry, fishing and hunting (0.306 fatalities per 
100,000 workers),
    2. Construction (0.113 fatalities per 100,000 workers), and
    3. Administrative and Support and Waste Management and Remediation 
Services (0.056 fatalities per 100,000 workers).
    For all other industry sectors combined, the average annual 
fatality rate was substantially smaller (0.009 fatalities per 100,000 
workers). The agriculture and construction sectors combined accounted 
for 58% of the fatalities during the study period (n=207).
    A CDC Morbidity and Mortality Weekly Report (MMWR) from 2008 
reported by Luginbuhl et al. investigated heat-related fatalities among 
all workers--and agriculture workers in particular--using BLS CFOI data 
from 1992-2006 (Luginbuhl et al., 2008). During the study period, the 
authors identified 423 deaths related to environmental heat in CFOI 
using the OIICS v1.01 event/exposure code 321 (Exposure to 
environmental heat) and nature code 072* (Effects of heat and light). 
Similar to the approach taken by Gubernot et al., the authors 
calculated rates using CPS estimates of the average annual worker 
population for denominators.
    For the overall workforce, the authors calculated an average annual 
incidence of 0.02 fatalities/100,000 workers, which is similar to the 
estimate reported by Gubernot et al. for 2000-2010 (0.022/100,000). Of 
the 423 fatalities identified, 102 (24%) occurred in the agriculture, 
forestry, fishing, and hunting sector (average annual fatality rate of 
0.16/100,000 workers) and 68 occurred among workers in crop production 
or support activities for crop production (annual fatality rate of 
0.39/100,000 workers). The rates for crop workers in North Carolina, 
Florida, and California were 2.36/100,000 workers, 0.74/100,000 
workers, and 0.49/100,000 workers, respectively. These findings were 
later included in a peer-reviewed article (Jackson and Rosenberg 2010).
    The editorial note accompanying this MMWR report mentioned, among 
other limitations, that CPS estimates used for denominators likely 
underestimate the number of crop workers--because of the potential lack 
of stable residences among these workers and the seasonal trends in 
employment--which would lead to an overestimate of risk for these 
workers. This limitation would presumably apply to any rate estimates 
calculated with CPS data for this specific population. To OSHA's 
knowledge, this is the only reported limitation in the included 
articles that would suggest a potential overestimation of incidence.
    A third paper analyzed BLS CFOI heat-related fatality data for the 
construction sector, estimating fatality rates for various occupations 
within the sector using Standard Occupational Classification codes 
(Dong et al., 2019). Using the OIICS v2.01 nature code 172* (Effects of 
heat and light) to determine heat-relatedness and CPS estimates for 
sector-wide and occupation-specific denominators, the authors 
identified 82 heat-related construction deaths between 2011-2016 and 
estimated an average annual fatality rate for the entire sector (0.15 
fatalities/100,000 workers) as well as for specific occupations. The 
occupations with the highest fatality rates included cement masons 
(1.62/100,000); roofers (1.04/100,000); helpers (1.03/100,000); brick 
masons (0.50/100,000); and laborers (0.29/100,000).
    Finally, a paper from 2005 by Mirabelli and Richardson identified 
heat-related fatalities using medical examiner records from North 
Carolina for the period from 1977 to 2001, including 15 years of data 
before the creation of CFOI (Mirabelli and Richardson 2005). They 
determined that heat was a primary or underlying cause of death based 
on ICD-9 codes. The researchers used the decedents' location and 
activities reported in the records to determine work-relatedness, and 
they excluded cases in which the decedent was <10 years old or those 
which involved manufactured sources of heat.
    The authors identified 40 occupational heat-related deaths. They 
classified 18 of these as farm workers and reported an annual fatality 
rate among these farm workers of 1.52 fatalities/100,000 workers. They 
reported 10 cases having occurred at a construction site but did not 
report a fatality rate for this group of workers. The average annual 
fatality rate for the entire State working population was 0.05 
fatalities/100,000 workers.
    As none of the identified papers reported fatality rates for the 
overall workforce for years beyond 2010, OSHA used the heat-related 
fatality counts reported by BLS for 2011-2022 (479 worker deaths) and 
employment estimates for the same years from CPS to calculate fatality 
rates for these years. For the denominator, OSHA used the total number 
of workers and average hours worked to estimate total FTEs per year. 
The average annual fatality rate during this period was 0.029 deaths/
100,000 FTEs.
A. Summary of Reported Occupational Heat-Related Fatalities
    OSHA identified multiple studies that calculated and reported 
annual incidence estimates for heat-related fatalities among workers 
using data from BLS CFOI or medical examiner records. These studies 
reported heat-related fatality rates across an entire workforce (either 
National or State), using the total workforce as the denominator. As 
mentioned above, this would understate the risk to workers who are 
actually exposed to heat on the job since the denominator includes a 
large percentage of workers who are not exposed to heat (e.g., office 
workers). Evidence in support of this claim comes from studies showing 
higher fatality rates when populations are stratified by sector, 
industry, or occupation. For instance, in Gubernot et al., 2015, the 
authors report an overall annual fatality rate of 0.022/100,000 workers 
whereas they report an annual fatality rate of 0.306/100,000 workers 
for workers in the agriculture, forestry, fishing, and hunting sector 
(a 14-fold difference). OSHA considers these stratified estimates to be 
more accurate estimates of the ``true'' incidence of heat-related 
fatalities among heat-exposed workers.

[[Page 70739]]



 Table V-1--Estimated Risk of Experiencing a Heat-Related Injury or Illness Annually and Over a 45-Year Working
                                                    Lifetime
----------------------------------------------------------------------------------------------------------------
                                                                                                     Expected
                                                                                                  number of non-
                                                                                  Average annual  fatal HRIs per
                 Population                             Source of data               rate (per        100,000
                                                                                      100,000      workers over
                                                                                     workers)         working
                                                                                                     lifetime
----------------------------------------------------------------------------------------------------------------
                                    Rates Based on Entire Working Populations
----------------------------------------------------------------------------------------------------------------
U.S., All Workers..........................  BLS SOII Injuries and Illnesses         \1\ 2.0-4.0          90-180
                                              Involving Days Away from Work.
State Working Populations..................  Workers' Compensation Records......     \2\ 3.1-6.0         140-270
State Working Populations..................  Emergency Department Visits and/or     \3\ 0.1-18.7         4.5-842
                                              Inpatient Hospitalization.
----------------------------------------------------------------------------------------------------------------
                              Rates Based on Sector-Specific Groups (2-digit NAICS)
----------------------------------------------------------------------------------------------------------------
Agriculture, forestry, fishing, and hunting  Washington State, 1995-2005........             5.2             234
                                             Washington State, 2006-2017........            13.0             585
                                             California, 2000-2017..............            38.6           1,737
Construction...............................  Washington State, 1995-2005........            12.1             545
                                             Washington State, 2006-2017........            10.8             486
                                             Wisconsin, 2010-2022...............             1.4            63.0
Public Administration......................  Washington State, 1995-2005........              12             540
                                             Washington State, 2006-2017........            10.3             464
                                             California, 2000-2017..............            35.3           1,589
                                             Wisconsin, 2010-2022...............             2.8             126
Administrative and support and waste         Washington State, 1995-2005........             3.9             176
 management and remediation services.        Washington State, 2006-2017........             4.6             207
                                             California, 2000-2017..............             8.8             396
                                             Wisconsin, 2010-2022...............             2.9             131
Transportation and warehousing.............  Washington State, 1995-2005........             3.5             158
                                             Washington State, 2006-2017........             3.8             171
                                             Wisconsin, 2010-2022...............             1.1            49.5
Utilities..................................  California, 2000-2017..............            11.4             513
Mining.....................................  California, 2000-2017..............            21.3             959
Wholesale Trade............................  Wisconsin, 2010-2022...............             1.9            85.5
----------------------------------------------------------------------------------------------------------------
                             Rates Based on Industry-Specific Groups (6-digit NAICS)
----------------------------------------------------------------------------------------------------------------
Farm labor contractors and crew leaders....  Washington State, 2006-2017........            77.3           3,479
Fire protection............................  Washington State, 1995-2005........            80.8           3,636
                                             Washington State, 2006-2017........            60.0           2,700
Structural steel and precast concrete......  Washington State, 2006-2017........            54.2           2,439
Poured concrete foundation and structural    Washington State, 1995-2005........            35.9           1,616
 contractors.
                                             Washington State, 2006-2017........            31.6           1,422
Roofing contractors........................  Washington State, 1995-2005........            59.0           2,655
                                             Washington State, 2006-2017........            29.0           1,305
Highway, street, and bridge construction...  Washington State, 1995-2005........            44.8           2,016
Site preparation construction..............  Washington State, 1995-2005........            35.9           1,616
----------------------------------------------------------------------------------------------------------------
                                    Rates Based on Major Occupational Groups
----------------------------------------------------------------------------------------------------------------
Protective services........................  California, 2000-2017..............            56.7           2,552
                                             Wisconsin, 2010-2022...............             4.1             185
Farming, fishing, and forestry.............  California, 2000-2017..............            35.9           1,616
Transportation and Material moving.........  California, 2000-2017..............            12.3             554
                                             Wisconsin, 2010-2022...............             2.6             117
Construction and extraction................  California, 2000-2017..............             8.9             401
                                             Wisconsin, 2010-2022...............             1.5            67.5
Building and grounds cleaning and            California, 2000-2017..............             6.0             270
 maintenance.
                                             Wisconsin, 2010-2022...............             1.5            67.5
Production.................................  Wisconsin, 2010-2022...............             1.6            72.0
Municipal workers in departments governing   Texas, 2009-2017...................           2,550         114,750
 streets and traffic, parks and recreation,
 utilities, and solid waste.
----------------------------------------------------------------------------------------------------------------
                                    Rates Based on Minor Occupational Groups
----------------------------------------------------------------------------------------------------------------
Fire Fighting and Prevention...............  Wisconsin, 2010-2022...............            14.7             662
Material Moving Workers....................  Wisconsin, 2010-2022...............             3.3             149
Metal and Plastic Workers..................  Wisconsin, 2010-2022...............             2.8             126
Motor Vehicle Operations...................  Wisconsin, 2010-2022...............             2.2            99.0
Assemblers and Fabricators.................  Wisconsin, 2010-2022...............             2.2            99.0
----------------------------------------------------------------------------------------------------------------
\1\ Ranges reflect varying annual average estimates between 2011-2020.
\2\ Ranges reflect values reported in Heinzerling et al., 2020, Bonauto et al., 2007, and Hesketh et al., 2020.
\3\ Ranges reflect values reported in or derived from Harduar Morano et al., 2015, Florida DOH 2011, Louisiana
  DOH 2023, Harduar Morano et al., 2016, CSTE, and Maricopa County Public Health Department.


[[Page 70740]]

IV. Limitations and Underreporting
    Evidence suggests that existing surveillance data undercount the 
total number of heat-related injuries, illnesses, and fatalities, among 
workers. The incident rates presented in the previous section are 
likely vast underestimates both because they use this surveillance data 
as the numerator when calculating incidence rates and because they 
overestimate the number of workers exposed to hot work environments 
(i.e., the denominator for incidence rates). These sources of 
uncertainty are described below.
A. Incidence Estimation
    Incidence estimates based on BLS data are likely to underestimate 
the true risk to workers who are exposed to specific hazards, like 
heat, in part because of difficulties in estimating the population of 
exposed workers. The current approach for BLS SOII rate estimates is to 
use the population of all workers in the U.S. for the denominator, not 
just those exposed to the hazard of interest. For instance, the 
denominators used for the risk estimates presented above would include 
most office workers who work in climate-controlled buildings and would 
therefore not have occupational exposure to the levels of heat stress 
that have been associated with adverse outcomes. For 2022, BLS reported 
116,435,925 full-time workers in the U.S. However, OSHA estimates the 
proposed standard would cover approximately 36 million workers, 
approximately one-third of the total full-time workers in the U.S. 
Therefore, BLS's use of a larger denominator likely underestimates risk 
because it includes workers not exposed to hazardous heat and therefore 
less likely to experience an HRI.
    The denominators for the annual incidence estimates presented above 
also include worker-time for the entire year, even though for many 
workers, exposure to potentially harmful levels of heat only occurs 
during the hottest months of the year. Including unexposed worker-time 
in the denominator has the effect of diluting the incidence estimates, 
meaning annual incidence estimates do not accurately represent the risk 
to workers when they are actually exposed to hazardous heat. The risk 
to workers whose jobs do expose them to harmful levels of heat, on the 
days on which those exposures occur, would therefore be expected to be 
higher than the estimates published by BLS. In addition, using total 
worker populations as a basis for estimating incidence likely will 
underestimate the risk to particularly susceptible workers, such as 
older workers, workers with pre-existing conditions, and workers not 
acclimatized to the heat.
    OSHA believes that studies that reported illness rates by sector or 
occupation provide evidence showing that the annual average illness 
rates reported across the entire workforce underestimate risk for 
exposed workers. For example, the Washington State and California 
workers' compensation studies found that heat-related illness rates for 
sector- or occupation-specific populations were substantially higher 
than the rates for the general working population in the State 
(Heinzerling et al., 2020; Bonauto et al., 2007; Hesketh et al., 2020). 
The sectors and occupations examined included those where exposure to 
hot environments was more likely than for the population as a whole 
(e.g., Construction and Agriculture, Forestry, Fishing, and Hunting). 
Additionally, many of the surveillance papers described above also 
reported the month in which the injury, illness, or fatality occurred 
and found that most cases were clustered in the hotter, summer months 
(e.g., June, July, and August). When researchers in Washington and 
Florida restricted their rate estimates to include data only for the 
third quarter (July, August, and September), they found rates that were 
several-fold higher than annual average illness rates over the whole 
population, which include many unexposed worker-days.
B. Undercounting of Cases
    The general underreporting and undercounting of occupational 
injuries and illnesses has been a topic of multiple government reports 
(e.g., Ruser, 2008; Miller, 2008; GAO, 2009; Wiatrowski, 2014). The 
authors of the peer-reviewed papers described in sections V.A.II., and 
V.A.III., above list underreporting or misclassification of cases as a 
limitation in their analyses that would have the effect of 
underestimating risk.
I. BLS SOII
    Two papers from the early 2000s that linked workers' compensation 
records to BLS SOII data found evidence that SOII missed a substantial 
amount of workers' compensation claims, depending on the State analyzed 
and the assumptions and methodology used (Rosenman et al., 2006; Boden 
and Ozonoff, 2008). In response to increased attention around this 
topic at the time, BLS funded additional research to examine the extent 
of underestimation in SOII and potential reasons (Wiatrowski, 2014). 
One of these studies involved linking multiple data sources (i.e., not 
just SOII and workers' compensation) for cases of amputation and carpal 
tunnel syndrome (Joe et al., 2014). The authors found that the State-
based surveillance systems included 5 times and 10 times more cases 
than BLS SOII, respectively.
    Another study conducted as part of this broader effort estimated 
that approximately 30% of all workers' compensation claims in 
Washington between 2003-2011 were not captured in BLS SOII (Wuellner et 
al., 2016). This included sectors with higher rates of heat-related 
injuries and illnesses, such as Agriculture, Forestry, Fishing, and 
Hunting (28% of cases uncaptured) and Construction (28% uncaptured) 
(Wuellner et al., 2016, Table III). The rate of underreporting was 
particularly high for large construction firms (Wuellner et al., 2016, 
Table IV).
    In response to the studies on SOII undercount, BLS authors have 
argued that differences in the inclusion criteria, scope, and purpose 
between BLS SOII and workers' compensation explain some of differences 
in the estimates and complicate the interpretations of the linkage-
based studies (Ruser, 2008; Wiatrowski, 2014). SOII estimates OSHA-
recordable injuries and illnesses each year and provides detailed case 
and demographic information (e.g., nature of injury) for a specific 
subset of the more severe cases (e.g., those involving days away from 
work). This scope (OSHA-recordable injuries and illnesses) inherently 
limits the ability for SOII to be used to estimate all occupational 
injuries and illnesses. Additionally, injuries and illnesses involving 
days away from work represent a limited percentage of the total 
injuries and illnesses reported to BLS. In 2022, these cases were 42% 
of total recordable cases, suggesting the case counts for HRIs in SOII 
could be missing up to 58% of all OSHA-recordable HRIs (i.e., those not 
involving days away from work) (https://www.bls.gov/iif/latest-numbers.htm).
    The injury and illness data that employers report to BLS come from 
the employer's OSHA Form 300 Log of Work-Related Injuries and Illnesses 
and OSHA Form 301 Injury and Illness Incident Report, so information on 
the quality of the data in these forms is relevant for understanding 
limitations of SOII. Through the Recordkeeping National Emphasis 
Program (NEP) from 2009-2012, OSHA found that almost half (47%) of 
establishments inspected by the agency had unrecorded and/or under-
recorded cases, which were more common at establishments that

[[Page 70741]]

originally reported low rates (Fagan and Hodgson, 2017). Several 
factors contributed to the under-recording and unrecording cases. 
First, in conducting thousands of interviews, the authors found that 
workers do not always report injuries to their employers because of 
fear of retaliation or disciplinary action. Second, some employers used 
on-site medical units, which the authors explained could contribute to 
underreporting (e.g., if these units were used to provide first aid 
when additional medical care, which would have warranted reporting on 
OSHA forms, should have been provided).
    Employers rely on workers to report injuries and illnesses that may 
otherwise be unobserved, but workers have multiple reasons to not do 
so. In addition to Fagan and Hodgson 2017, multiple studies have 
interviewed or surveyed workers on this topic. A recent systematic 
review of 20 studies found that 20-74% of workers--which included 
cleaning staff, carpenters, construction workers, and healthcare 
workers--did not report injuries or illnesses to management (Kyung et 
al., 2023). Some of the researchers asked workers about the barriers to 
reporting, which included fear, a lack of knowledge on the reporting 
process, and considering the injury to be a part of the job or not 
serious.
    Finally, employers are disincentivized from reporting injuries and 
illnesses on their OSHA logs. Disincentives for reporting include 
workers' compensation premiums being tied to injury and illness rates, 
competition for contracts involving safety records, and a perception 
that reporting will increase the probability of being inspected by OSHA 
(GAO, 2009).
    In interviews with employers selected to respond to SOII, 
researchers found that 42% of them were not maintaining a log (Wuellner 
and Phipps, 2018). In the same study, researchers found evidence to 
suggest that misunderstandings about the reporting requirements would 
likely lead to employers underreporting cases involving days away from 
work. A similar study conducted among SOII respondents in Washington 
State found that 12% weren't maintaining a log and 90% weren't 
complying with some aspect of OSHA's recordkeeping requirements 
(Wuellner and Bonauto, 2014).
    While the general underreporting articles described here are not 
specific to heat, Heinzerling et al. 2020 examined rates of heat-
related injuries and illnesses among workers in California and found 
that California's workers' compensation database, WCIS, had 3-6 times 
the number of heat-related cases between 2009-2017 than the official 
BLS SOII estimates for California for each year in that period 
(Heinzerling et al., 2020). Part of the reason for this discrepancy 
could be the difference in inclusion criteria between the two datasets, 
however, it is still a useful estimate for contextualizing the 
potential magnitude of underreporting of heat-related cases when using 
only SOII. While outside the U.S., a recent survey of 51 Canadian 
health and safety professionals in the mining industry found that 71% 
of respondents believed HRIs were underreported (Tetzlaff et al., 
2024).
II. Workers' Compensation
    While workers' compensation data may capture injury and illness 
cases not included in BLS SOII, the data are not available for the 
entire U.S., as insurance coverage and reporting requirements vary 
across States, and most States do not have single-payer systems. 
Therefore, the majority of claims data are compiled by various insurers 
and not within a single database. Even when the data are available for 
an entire State, it is generally presumed that not all worker injuries 
and illnesses are captured in these data, in part because of 
eligibility criteria and in part because of underutilization of 
workers' compensation for reimbursement of work-related medical 
expenses.
    Multiple papers have examined the extent to which and reasons why 
workers don't always use workers' compensation insurance to pay for 
work-related medical expenses and other reimbursable expenses. Some 
reasons workers have reported for not filing workers' compensation 
claims include fear, a lack of knowledge, ``too much trouble'' or 
effort, and considering the injury to be a part of the job or not 
serious (Kyung et al., 2023; Scherzer et al., 2005). Using the 
Washington State Behavioral Risk Factor Surveillance System (BRFSS), a 
telephone survey, Fan et al. (2006) found that 52% of the respondents 
in 2002 reporting a work-related injury or illness filed a workers' 
compensation claim. Using similar methodology across 10 States, Bonauto 
et al. (2010) found that among respondents who reported a work-related 
injury, there was a wide range in the proportion who reported having 
their treatment paid for by workers' compensation by State--47% in 
Texas to 77% in Kentucky (with a median of 61%). A study from 2013 
estimated that 40% of work-related ED visits were paid for by a source 
other than workers' compensation (Groenewold and Baron, 2013). Worker 
race, geography, and having an illness rather than an injury were all 
predictors of whether workers' compensation was the expected payer.
    There are a few papers that suggest this phenomenon is occurring 
for heat-related outcomes. Harduar Morano et al. 2015 (described above 
in Section V.A.II., Reported Annual Incidence of Nonfatal Occupational 
Heat-Related Injuries and Illnesses) found that across several 
southeastern States, workers' compensation as expected primary payer 
alone captured 60% of all emergency department visits and inpatient 
hospitalizations, which varied by State (50-80% for emergency 
department visits and 38-84% for inpatient hospitalizations) (Harduar 
Morano et al., 2015). Similarly, in the 2011 report by the Florida 
Department of Health (described above in Section V.A.II., Reported 
Annual Incidence of Nonfatal Occupational Heat-Related Injuries and 
Illnesses), 83% of claims identified were captured by workers' 
compensation as primary payer (Florida DOH, 2011). It should be noted 
that these percentages are influenced by the total number of captured 
cases and in both sources the authors presume that they did not capture 
all relevant cases.
III. Hospital Discharge Data
    Hospital discharge data are the only surveillance data presented in 
this risk assessment for which work-relatedness is not an inclusion 
criterion; therefore, researchers relying on this data need to take an 
additional step to assess work-relatedness for each case that 
introduces the possibility that work-related cases are not recognized 
as such and are thus excluded. Researchers identifying work-related 
cases typically use a combination of workers' compensation as the 
primary payer or ICD codes for external cause of injury. As discussed 
in the previous section, workers' compensation is not always used by 
workers, so relying on this variable will lead to undercounting. For 
external cause of injury codes (e.g., E900.9 Excessive heat of 
unspecified origin), researchers have found that these are not always 
present or accurate for work-related injury cases (Hunt et al., 2007), 
which isn't unexpected given that they aren't required for 
reimbursement. For instance, codes indicating the location of 
occurrence were present in 43% of probable work-related injury cases 
the authors reviewed (Hunt et al., 2007). Harduar Morano and Watkins 
(2017) used external cause of injury codes to identify work-related 
emergency department visits and hospitalizations for heat-related 
illnesses in Florida. They found that 2.8% of emergency

[[Page 70742]]

department visits, 1.2% of hospitalizations, and 0% of deaths were 
identified solely by an external cause of injury code for work.
    Both workers' compensation claims and hospitalization data are also 
affected by the accuracy of diagnostic codes for identifying heat-
related cases. While the use of ICD codes for surveillance of heat-
related deaths, illnesses, and injuries is widely accepted, it is not 
infallible, as these codes are designed for billing rather than 
surveillance. The use of specific codes is up to the discretion of 
healthcare providers, so practices may vary by provider and facility. 
Healthcare providers may not always recognize that a patient's symptoms 
are heat-related and thus, they may not record a heat-specific ICD 
code. For example, a patient who presents to the emergency room after 
fainting would likely be diagnosed with ``syncope'' (the medical term 
for fainting). If the provider is aware that the patient fainted due to 
heat exposure, they should record a heat-specific ICD-10 code, T67.1 
Heat syncope. However, if the provider is unaware that the patient 
fainted due to heat exposure (or otherwise fails to recognize the 
connection between the two), they may record a non-heat-specific ICD-10 
code, R55 Syncope and collapse. Researchers suspect underreporting when 
ICD codes are used for surveillance of HRIs (Harduar Morano and 
Watkins, 2017) and recommend researchers use all possible fields 
available (e.g., primary diagnosis, secondary diagnosis, underlying 
cause of death, contributing cause of death).
    Researchers examining trends in heat-related illnesses using 
electronic health records for the Veterans Health Administration 
identified a dramatic increase in cases when ICD-10 was adopted, 
suggesting that the coding scheme in ICD-9 may have led to systematic 
underreporting of heat-related cases, at least for this population 
(Osborne et al., 2023). The authors also note that 8.4% of the HRI 
cases they identified were captured using unstructured fields (e.g., 
chief complaint, reason for admission) and not ICD codes.
    Not all sick and injured workers go to an emergency department or 
hospital and those that do are likely to be more severe cases. 
Unfortunately, estimating the proportion of injured and sick workers 
who do go to the hospital or emergency room is difficult, given a lack 
of data on this topic. In a 1998 CDC Morbidity and Mortality Weekly 
Report written by NIOSH safety researchers, the authors reported an 
analysis of unpublished data from the 1988 National Health Interview 
Survey (NHIS) Occupational Health Supplement which found that 34% of 
all occupational injuries were first treated in hospital emergency 
departments, 34% in doctors' offices/clinics, 14% in work site health 
clinics, and 9% in walk-in clinics (NIOSH DSR 1998). 1988 was the last 
year that NIOSH asked that question in the NHIS.
    Care-seeking for workers experiencing heat-related symptoms 
specifically may be low. In a study evaluating post-deployment survey 
response data among a subset of the Deepwater Horizon oil spill 
responders (U.S. Coast Guard), Erickson et al. found that less than 1% 
of respondents reported seeking medical treatment for heat-related 
illness, yet 12% reported experiencing any heat-related symptoms 
(Erickson et al., 2019).
IV. BLS CFOI
    CFOI is well-regarded as the most complete and authoritative source 
on fatal workplace injuries. However, the approach used to classify the 
event and nature codes by BLS is not immune to misclassification of 
heat-related deaths. BLS relies on death certificates, OSHA fatality 
reports, news articles, and coroner reports (among other sources) to 
determine the primary or contributing causes of death. The criteria for 
defining a heat-related death or illness can vary by State, and among 
physicians, medical examiners, and coroners. Additionally, individuals 
who fill out death certificates are not necessarily equipped to make 
these distinctions or confident in their accuracy (Wexelman, 2013). 
Depending on State policies, individuals performing this role may be a 
medical professional or an elected official with limited or no 
medically relevant experience (National Research Council, 2009; CDC, 
2023).
    Researchers estimating fatality rates attributable to heat in the 
overall U.S. population using historical temperature records have 
produced much higher counts than approaches solely using death 
certificates (Weinberger et al., 2020). While outside the U.S., a 
recent study examining causes of death among migrant Nepali workers in 
Qatar from 2009-2017 demonstrated that deaths coded as cardiovascular-
related (e.g., ``cardiac arrest'') among these mostly young workers 
were unexpectedly common and correlated with higher wet bulb globe 
temperatures, suggesting that these deaths may have been heat-related 
but not coded as such (Pradhan et al., 2019). Heat-related deaths are 
uniquely hard to identify if the medical professional didn't witness 
the events preceding the death, particularly because heat can 
exacerbate an existing medical condition, acting as a contributing 
factor (Luber et al., 2006).
C. Summary
    In conclusion, the available evidence indicates that the existing 
surveillance data vastly undercount cases of heat-related injuries and 
illnesses among workers. OSHA additionally believes that the inclusion 
of unexposed worker-time in the denominator for incidence estimates 
underestimates the true risk among heat-exposed workers.
V. Requests for Comments
    OSHA requests information and comments on the following questions 
and requests that stakeholders provide any relevant data, information, 
or additional studies (or citations) supporting their view, and explain 
the reasoning for including such studies:
     Are there additional data or studies OSHA should consider 
regarding the annual incidence of HRIs and heat-related fatalities 
among workers?
     OSHA has identified data from cohort-based and time series 
studies that would suggest higher incidence rates than data from 
surveillance datasets (e.g., BLS SOII, workers' compensation claims). 
Are there other data from cohort-based or time series studies that OSHA 
should rely on for determining risk of HRIs to heat-exposed workers?
     Are employers aware of occupational HRIs that are not 
reported through BLS SOII, workers' compensation claims, or hospital 
discharge data? How commonly do HRIs occur that are not recorded on 
OSHA 300 logs?
     Are there additional data or studies that OSHA should 
consider regarding the extent of underreporting and underestimating of 
HRIs or heat-related fatalities?

B. Basis for Initial and High Heat Triggers

I. Introduction
    In this section, OSHA presents the evidence that forms the basis of 
the heat triggers contained in the proposed standard. These triggers 
are based on the heat index and wet bulb globe temperature (WBGT). The 
WBGT triggers are based on NIOSH exposure limits (i.e., the REL and 
RAL), which are supported by empirical evidence dating back to the 
1960s and have been found to be highly sensitive in capturing 
unsustainable heat exposures.
    Although there are no consensus-based heat index exposure limits 
for workers, the question of which heat

[[Page 70743]]

index values represent a highly sensitive and appropriate screening 
threshold for heat stress controls in the workplace has been evaluated 
in the peer-reviewed scientific literature. The evidence described 
below provides information on the sensitivity of alternative heat index 
values, that is, the degree to which a particular heat index value can 
be used to screen for potential risk of heat-related injuries and 
illnesses (HRIs) and fatalities. OSHA looked at both experimental and 
observational evidence, including efforts to derive more accessible and 
easily understood heat index-based triggers from WBGT-based exposure 
limits, to preliminarily determine appropriate heat index values for 
triggering heat stress control measures. Each of these evidence streams 
has strengths and limitations in informing this question.
    Relevant experimental evidence in the physiology literature is 
often conducted in controlled laboratory settings among healthy, young 
volunteers, but the conditions may not always mimic conditions 
experienced by workers (e.g., workers often experience multiple days in 
a row of working in high temperatures). Observational evidence does not 
have this limitation because the data are collected among actual 
workers in real-world settings. However, observational evidence is 
potentially affected by exposure misclassification since exposure 
metrics are often derived from local weather stations and rely on 
maximum daily values. Experimental data does not have this limitation, 
since the laboratory conditions are highly controlled, including the 
exposure levels.
    OSHA used both streams of evidence to support proposing an initial 
heat trigger of 80 [deg]F (heat index) and a high heat trigger of 90 
[deg]F (heat index). The observational evidence that OSHA identified 
suggests that the vast majority of known occupational heat-related 
fatalities occur above the initial heat index trigger, making it a 
sensitive trigger for heat-related fatalities. The vast majority of 
nonfatal occupational HRIs also occur above this trigger. The 
experimental evidence (specifically the WBGT-based exposure limits) 
also suggests that when there is high radiant heat, a heat index of 90 
[deg]F would be an appropriate time to institute additional controls 
(e.g., mandatory rest breaks). This is supported by observational 
evidence that shows a rapidly declining sensitivity above a heat index 
of 90 [deg]F. OSHA has preliminarily concluded that the experimental 
evidence also supports the selection of these triggers as highly 
sensitive and therefore protective.
II. Observational Evidence
    To determine an appropriate initial heat trigger, OSHA sought to 
identify a highly sensitive screening level above which the majority of 
fatal and nonfatal HRIs occur. This could presumably be used to 
identify the environmental conditions for which engineering and 
administrative controls would be most important to prevent HRIs from 
occurring. One challenge for determining this trigger level is that 
many factors influence an individual's risk of developing an HRI. In 
addition to workload, PPE, and acclimatization status, the risk of 
developing an HRI is also influenced by workers' abilities to self-pace 
at their jobs as well as whether there had been exposure to hot 
conditions on the prior day(s). There are also medications and 
comorbidities that may increase workers' risk of HRIs (see discussion 
in Section IV.O., Factors that Affect Risk for Heat-Related Health 
Effects).
    The observational studies reviewed by OSHA used retrospective 
temperature and humidity data matched to the locations where HRIs and 
fatalities occurred over a period of time. Although these studies did 
not account specifically for workload, PPE use, acclimatization status, 
or other relevant factors, the HRI cases studied included worker 
populations where these factors were likely present to varying degrees. 
Therefore, OSHA has preliminarily determined that retrospective 
observational data collected among workers who have experienced fatal 
or nonfatal HRIs on the job is valuable to informing a screening level 
that reflects the presence of these multiple risk factors among worker 
populations. These studies are summarized in the following sections.
A. Fatalities
    In a doctoral dissertation from 2015, Gubernot matched historic 
weather data to the heat-related fatalities reported in BLS CFOI 
(fatality data described in Section V.A., Risk Assessment) between 
2000-2010 (Gubernot, 2015). Gubernot used historic, weather monitor-
based temperature and dew point measurements from the National Climatic 
Data Center to recreate the heat index (using daily maximum temperature 
and daily average dew point) on the day of each fatality. If there was 
not already a monitor in the county where a fatality occurred, then the 
next closest weather monitor to that county was used. Of the 327 
fatalities identified as being related to ambient heat exposure (i.e., 
cases with secondary heat sources, like ovens, were excluded), 96.3% 
occurred on a day with a calculated heat index above 80 [deg]F and 
86.9% occurred on a day above 90 [deg]F. Using a higher threshold such 
as a heat index of 95 [deg]F would have only captured approximately 71% 
of fatalities (estimated from Figure 4-2 of the study). The author also 
evaluated how many cases occurred on a day when a National Weather 
Service (NWS)-defined excessive heat event (EHE) was declared. In a 
directive to field offices, the NWS outlines when offices should issue 
excessive heat warnings--when there will be 2 or more days that meet or 
exceed a heat index of 105 [deg]F for the Northern U.S. and 110 [deg]F 
for the Southern U.S., with temperatures not falling below 75 [deg]F 
(although local offices are allowed to use their own criteria) (NWS, 
2024a). Gubernot appears to have used a simpler criterion to evaluate 
the sensitivity of these EHEs--whether the heat index on the day of the 
fatality was at or above 105 [deg]F for northern States and at or above 
110 [deg]F for southern States. Only 42 fatalities (12.8%) occurred on 
days meeting the EHE definitions, suggesting EHEs are not a sensitive 
trigger for occupational heat-related fatalities. During the SBREFA 
process, small entity representatives suggested that OSHA consider the 
NWS EHE definitions as options for the initial and/or high heat 
triggers, but based on these findings (and those reported in other 
studies summarized in this section), OSHA has preliminarily determined 
that these criteria are not sensitive enough and would not adequately 
protect workers.
    Some limitations of this analysis include the use of nearest-
monitor exposure assignment, as well as the use of maximum temperature 
with average dew point to calculate heat index, both of which may 
introduce exposure misclassification. Although the author did not refer 
to the latter as a daily maximum heat index, this estimate would most 
closely approximate that value, which would suggest that workers were 
likely exposed to heat index values below that level during the work 
shift leading up to the fatality.
    In a meta-analysis published in 2020, Maung and Tustin (both 
affiliated with OSHA at the time) conducted a systematic review of 
studies, such as the one described above by Gubernot, where researchers 
retrospectively assigned heat exposure estimates to occupational heat-
related fatalities (Maung and Tustin, 2020). The purpose of their meta-
analysis was to identify a heat index threshold below which 
occupational heat-related fatalities do not occur (i.e., a highly 
sensitive

[[Page 70744]]

threshold). Maung and Tustin identified 418 heat-related fatalities 
among civilian workers across 8 studies. Approximately three quarters 
of these civilian fatalities (n=327; 78%) came from Gubernot 2015. The 
authors found a heat index threshold of 80 [deg]F to be highly 
sensitive for civilian workers--96% of fatalities (402 of 418) occurred 
on days with a heat index estimate at or above this level. A heat index 
threshold of 90 [deg]F had slightly lower sensitivity--approximately 
86% (estimated from table 1 and figure 3 of their study). Similar to 
the findings reported in Gubernot 2015, one of the NWS thresholds for 
issuing heat advisories (heat index of 105 [deg]F) did not appear to be 
a sensitive trigger, missing 68% of civilian worker fatalities.
    The limitations for Gubernot 2015 apply to this analysis as well. 
These analyses (including the data from Gubernot, 2015) were limited to 
outdoor workers, potentially limiting the generalizability of the 
findings. This analysis also relied on single values (e.g., daily 
maximum heat index) to capture exposure across a work shift. As pointed 
out by Maung and Tustin, it is important to consider that exposure 
characterizations using daily maximum heat index likely over-estimates 
the exposures that workers experience throughout the shift leading to 
the fatality. For example, a fatality occurring on a day with a daily 
maximum heat index of 90 [deg]F likely involved prolonged exposure to 
heat index values in the 80s [deg]F.
    In 2019, a group of OSHA researchers published a similar analysis 
for both fatal and nonfatal HRIs reported to OSHA in 2016 among outdoor 
workers (Morris CE et al., 2019). They identified 17 fatalities in this 
subset and used nearest weather station data to estimate daily maximum 
heat index on the day of the fatality. All 17 fatalities occurred on a 
day with a daily maximum heat index of at least 80 [deg]F (the lowest 
was at 88 [deg]F). A daily maximum heat index of 90 [deg]F had a 
sensitivity of approximately 94%, while 100 [deg]F had a sensitivity of 
approximately 35%. A major limitation with this analysis is its small 
sample size (n=17 fatalities).
B. Non-Fatalities
    Morris et al., identified 217 nonfatal HRIs among outdoor workers 
reported to OSHA in 2016 (Morris CE et al., 2019). They found that 99% 
of these cases happened on a day with a daily maximum heat index of at 
least 80 [deg]F. There is a steep decline in sensitivity for daily 
maximum heat index values in the 90s [deg]F--89% for 90 [deg]F but 
approximately 58% for 100 [deg]F (estimated from Figure 5 of the study 
which combines fatal and nonfatal cases)--suggesting that many nonfatal 
HRIs occur on days when the heat index does not reach 100 [deg]F. One 
limitation of this dataset is potential selection bias, because the 
dataset only included cases that were reported to OSHA. This study 
therefore did not include cases in State Plan States.
    A much larger analysis conducted among emergency department (ED) 
visits in the Southeastern U.S. was published by Shire et al. (Shire et 
al., 2020). The authors identified 5,017 hyperthermia-related ED visits 
among workers in 5 southeastern States (Florida, Georgia, Kentucky, 
Louisiana, and Tennessee) between May and September in 2010-2012. While 
the previously described studies used nearest monitor data, Shire et 
al. used data from the North American Land Data Assimilation System 
(NLDAS), which incorporates both observation and modeled data to fill 
in gaps between locations of monitors, providing data at a higher 
geographic resolution (0.125[deg] grid). Since the authors only had ED 
visit data at the county level, they used the NLDAS data to compute 
population-weighted, county-level estimates of daily maximum heat index 
using all the grids within each county. They found that approximately 
99% of ED visits occurred on days with a daily maximum heat index of at 
least 80 [deg]F and about 95% of cases on days with a maximum heat 
index of at least 90 [deg]F. Approximately 54% of cases occurred on 
days with a daily maximum heat index of 103 [deg]F or higher. This 
further supports the finding from Morris et al. (2019) that sensitivity 
declines steeply above a heat index of 90 [deg]F. One limitation of 
this analysis is the use of the emergency department location as the 
basis for the exposure assignment, which has the potential to introduce 
exposure misclassification if workers were working far away from the ED 
facility.
    In a 2016 doctoral dissertation, Harduar Morano conducted a 
retrospective analysis of 3,394 heat-related hospitalizations and ED 
visits among Florida workers in May-October between 2005-2012, using 
data from the weather monitor nearest to the zip codes where the 
hospitalizations and ED visits occurred to characterize heat exposure 
(Harduar Morano, 2016). The vast majority of cases occurred on a day 
with a daily maximum heat index of at least 80 [deg]F, with 
approximately 91% of cases occurring on a day with a maximum heat index 
of at least 90 [deg]F (estimated from Figure 6-4). There was also a 13% 
increase in the HRI hospitalization and ED visit rate for every 1 
[deg]F increase in heat index at values below 99 [deg]F (Figure 6-4, 
Lag 0 plot of the study), suggesting that potential triggers in the 
mid-to-high 90's would increasingly miss many cases. One limitation of 
this analysis and that conducted by Shire et al. is that 
hospitalization and ED visit data did not include enough information to 
distinguish between indoor vs outdoor workers; it is possible that 
indoor workers could have been exposed to conditions not captured by 
the weather data (such as working near hot industrial processes).
    In addition, four studies of workers' compensation data in 
Washington State--three of which were reported in Section V.A., Risk 
Assessment--have examined maximum temperature or heat index on the days 
of reported HRIs (Bonauto et al., 2007; Spector et al., 2014; Hesketh 
et al., 2020; Spector et al., 2023). Hesketh et al., 2020 (an update on 
Bonauto et al., 2007) matched weather data to addresses for the HRI 
claims in the State's workers' compensation database between 2006 and 
2017 (Hesketh et al., 2020). They found that, of the 905 claims for 
which they had temperature data, over 75% of HRIs occurred on days with 
a maximum temperature of at least 80 [deg]F and approximately 50% of 
claims occurred on days with a maximum temperature of at least 90 
[deg]F (estimated from Figure 2). They also reported that approximately 
75% of claim cases occurred when the hourly maximum temperature was at 
least approximately 79 [deg]F. This paper is part of the rationale for 
Washington State lowering the trigger level in its heat-specific 
standard from 89 [deg]F to 80 [deg]F--the old trigger of 89 [deg]F had 
missed 45% of cases in this dataset (Washington Dept. of Labor & 
Industries, 2023). A similar study published in 2023 expanded the 
dataset used by Hesketh et al. to include HRI claims from 2006 to 2021 
(n=1,241) (Spector et al., 2023). The authors used gridded 
meteorological data from the PRISM Climate Group at Oregon State 
University and geocoded accident location (or business location or 
provider location if accident location was unable to be used) to 
determine the maximum temperature on the day of the event. They found 
that 76% of HRI claims occurred on a day with a maximum temperature of 
at least 80 [deg]F (this increased to 79% when restricted to cases that 
were ``definitely'' or ``probably'' outdoors). A major limitation of 
these studies is the use of ambient temperature, limiting the ability 
to compare findings to other papers that relied on the heat index. In

[[Page 70745]]

Spector et al. 2014, the authors calculated the daily maximum heat 
index for each county with an HRI in their dataset on the date of 
injury (Spector et al., 2014). They obtained the county of injury and, 
when not available, imputed the location of the injury rather than 
using the employer address, which is assumed to be more accurate for 
characterizing exposure. In their analysis of 45 agriculture and 
forestry worker HRI claims between 1995-2009 that had corresponding 
weather data, Spector et al. found that 75% of HRI claims occurred on 
days when the maximum heat index was at least 90 [deg]F, whereas only 
50% occurred on days when it was at least 99 [deg]F and 25% for 106 
[deg]F.
C. Summary
    In summary, researchers have identified a heat index of 80 [deg]F 
as a highly sensitive trigger for heat-related fatalities (capturing 
96-100% of fatalities) and nonfatalities (99-100%) among workers 
(excluding results from Washington State). When looking at ambient 
temperature, researchers in Washington found that 75-76% of HRI claims 
occurred on a day with a maximum ambient temperature of 80 [deg]F or 
greater. Multiple studies additionally identified a rapidly declining 
sensitivity above a heat index of 90 [deg]F, suggesting that additional 
protective measures (e.g., observation for signs and symptoms of HRIs) 
are needed once the heat index reaches approximately 90 [deg]F.
    One of the common limitations of the analyses presented in this 
section is the use of a single reading (e.g., daily maximum heat index) 
to capture each affected worker's exposure on the day of the event. In 
reality, conditions fluctuate throughout the day, so relying on maximum 
measures would likely overestimate heat exposure across the workday. 
The use of nearest monitor weather data is also likely to lead to 
exposure misclassification. The inclusion of indoor workers in some of 
the studies is also a limitation, since the exposure for those workers 
could be very different (e.g., if there is process heat). In Spector et 
al. 2023, the authors noted an increase in the percent of cases 
occurring on days with a maximum temperature of 80 [deg]F when 
restricting to cases that definitely or probably occurred outdoors. In 
all these studies, researchers can only examine conditions for the 
cases that were captured in the surveillance systems. There could be a 
bias such that cases occurring on hotter days were more likely to have 
been coded as heat-related and included in these databases. Failure to 
ascertain HRI cases occurring at lower heat indices could have skewed 
the findings upwards, making it appear that hotter thresholds were more 
sensitive than they actually were. Finally, the use of heat index (or 
ambient temperature) ignores the impacts of air movement as well as 
radiant heat, which can substantially increase the heat stress a worker 
is exposed to and increase the risk of an HRI.
III. Experimental Evidence
    NIOSH has published exposure limits based on WBGT in its Criteria 
for a Recommended Standard going back multiple decades.\3\ These 
exposure limits--the REL and RAL--account for the contributions of wind 
velocity and solar irradiance, in addition to ambient temperature and 
humidity. (ACGIH has published similar exposure limits--the TLV and 
AL.) In addition to WBGT, NIOSH and ACGIH heat stress guidelines 
require the user to account for metabolic heat production (through the 
estimation of workload) and the contributions of PPE and clothing. The 
user adds an adjustment factor to the measured WBGT to account for the 
specific clothing or PPE worn (specifically those ensembles that impair 
heat loss) and uses a formula based on workload to estimate the 
exposure limit. They then compare the measured (or adjusted, if using a 
clothing adjustment factor) WBGT to the calculated exposure limit to 
determine if the limit is exceeded. Work-rest schedules with increasing 
time spent on break can further increase the exposure limit.
---------------------------------------------------------------------------

    \3\ NIOSH plays an important role in carrying out the purpose of 
the OSH Act, including developing and establishing recommended 
occupational safety and health standards (29 U.S.C. 671).
---------------------------------------------------------------------------

    These exposure limits and guidelines are based in empirical 
evidence, such as laboratory-based trials conducted in the 1960s and 
1970s. This basis for WBGT exposure limits is described in detail by 
both NIOSH and ACGIH (NIOSH, 2016; ACGIH, 2017). These exposure limits 
have been tested and found to be highly sensitive (100%) in modern 
laboratory conditions in capturing unsustainable heat exposures (i.e., 
when a steady increase in core temperature is observed) (Garzon-
Villalba et al., 2017). Among workers in real-world settings, these 
WBGT-based exposure limits have been found to be highly sensitive for 
fatal outcomes (100% in one study; 92-100% in another) and, although 
slightly less so, still sensitive for nonfatal outcomes (73% in one 
study; 88-97% in another); however, these studies are limited by their 
small sample size and retrospective characterization of workload, 
acclimatization status, and clothing/PPE use (which are required for 
accurately estimating WBGT-based exposure limits) (Tustin et al., 
2018b; Morris CE et al., 2019).
    Two papers have attempted to apply the concepts of the WBGT-based 
exposure limits to the more easily accessible and understood heat index 
metric. Based on the relationship between WBGT and heat index, Bernard 
and Iheanacho developed a screening tool that reflects heat stress risk 
based on heat index and workload category--light (180 W), moderate (300 
W), and heavy (415 W)--using assumptions about radiant heat but 
ignoring the contributions of wind and clothing (Bernard and Iheanacho, 
2015). To do this, they created a model predicting WBGT from the heat 
index. From this model, WBGT estimates were produced within a 1 [deg]C 
range for heat index values of 100 [deg]F or more but the model was 
less accurate at heat index values below 100 [deg]F. Using their 
reported screening table, which allows the user to adjust for low vs 
high radiant heat, an acclimatized worker performing a heavy (415 W) 
workload in high radiant heat outdoors would be above the WBGT-based 
exposure limit and in need of a break at a heat index of 90 [deg]F. The 
same worker, if unacclimatized, would be above the exposure limit at a 
heat index of 80 [deg]F. These findings support the provision of 15-
minute breaks at a heat index of 90 [deg]F in OSHA's proposed standard, 
as well as the provision requiring these breaks for unacclimatized 
workers at a heat index of 80 [deg]F (unless the employer is following 
the gradual acclimatization schedule and providing breaks if needed). 
The authors noted that high radiant heat indoors could require even 
greater adjustments to the heat index. As further evidence for the need 
to adjust these values for radiant heat exposure, Morris et al. (2019) 
reported that for the days on which HRIs occurred in their dataset, 
cloud cover was often minimal suggesting there was exposure to high 
radiant heat when the HRIs occurred.
    More recently, Garz[oacute]n-Villalba et al. used an experimental 
approach to derive workload-based HI heat stress thresholds 
(Garz[oacute]n-Villalba et al., 2019). The researchers used data from 
two progressive heat stress studies of 29 acclimatized individuals. 
Participants were assigned different work rates and wore different 
clothing throughout the trials, serving as their own controls. Once 
thermal equilibrium was established, the ambient temperature was 
increased in five-minute intervals while holding relative humidity

[[Page 70746]]

constant. The critical condition defined for each subject was the 
condition at which there was a transition from a stable core body 
temperature to an increasing core body temperature (i.e., the point at 
which heat exposure became unsustainable). Using the results from these 
trials, the authors established an equation deriving a heat index 
exposure limit (equivalent to the TLV or REL) at different metabolic 
rates for a worker wearing woven clothing:

HI benchmark ([deg]C) = 49-0.026 M

Where M is workload in Watts.
    Garz[oacute]n-Villalba et al. assessed the effectiveness of the 
proposed heat index thresholds for predicting unsustainable heat stress 
by using receiver operating characteristic curves and area-under-the-
curve (AUC) values to determine predictive power (this technique is 
commonly used to evaluate the predictive power of diagnostic tests). 
The AUC value for the proposed heat index thresholds with subjects 
wearing woven clothing was 0.86, which is similar to that of the WBGT-
based thresholds, based on the authors' prior analysis (Garz[oacute]n-
Villalba et al., 2017). This result showed that the heat index 
thresholds derived by Garz[oacute]n-Villalba et al. (2019) would 
reasonably identify unsustainable heat exposure conditions.
    Compared to the heat index thresholds proposed by Bernard and 
Iheanacho (2015), the heat index thresholds proposed by Garz[oacute]n-
Villalba et al. are the same at low metabolic rates (111 [deg]F for 180 
W) but higher at higher metabolic rates: 105.8 [deg]F versus 100 [deg]F 
at 300 W and 100.4 [deg]F versus 95 [deg]F at 415 W (Note: these values 
are unadjusted for radiant heat). This is likely because the ACGIH 
WBGT-based exposure limits, upon which Bernard and Iheanacho based 
their heat index thresholds, are intentionally more conservative at 
higher metabolic rates, whereas Garz[oacute]n-Villalba used a less 
conservative linear model to derive their heat index thresholds 
(Garz[oacute]n-Villalba et al., 2019). When adding an adjustment for 
full sunshine provided by the authors, the proposed heat index-based 
exposure limit derived from the Garz[oacute]n-Villalba et al. (2019) 
equation for a worker performing a very heavy workload (450 W) is 92.8 
[deg]F.
    Thus, laboratory-derived heat index thresholds for unsustainable 
heat exposure are higher than heat index thresholds shown in 
observational studies to be sensitive for predicting the occurrence of 
HRIs. There are several reasons that may explain why values determined 
to be sensitive in laboratory settings are higher than those reported 
among workers in real-world settings. For one, volunteers in laboratory 
studies are often young, healthy, and euhydrated (i.e., beginning the 
trial adequately hydrated). They are also not exposed to consecutive 
days of heat exposure for eight-hour or longer work shifts. Working in 
hot conditions on the prior day has been demonstrated in the literature 
to be a risk factor for HRIs, even among acclimatized individuals 
(Garz[oacute]n-Villalba et al., 2016; Wallace et al., 2005). Therefore, 
the use of volunteers and exposure conditions in laboratory-based 
trials may not always provide good proxies for workers and the 
environments in which they work. There is also significant inter-
individual variability in heat stress tolerance, which may mean trial 
studies with few participants might not capture the full range of heat 
susceptibilities faced by workers.
    In summary, long-established and empirically validated occupational 
exposure limits exist for WBGT. In observational studies, WBGT exposure 
limits have been found to be highly sensitive for detecting fatal HRIs 
among workers and, although slightly less so, still sensitive for 
nonfatal outcomes (although these studies are limited by small sample 
size and retrospective work characterization). Research efforts to 
crosswalk the WBGT-based exposure limits to the more accessible heat 
index metric have demonstrated that a heat index of 90-92.8 [deg]F 
would represent an appropriate trigger for controls such as mandatory 
rest breaks for acclimatized workers performing heavy or very heavy 
workloads in high radiant heat conditions (Bernard and Iheanacho, 2015; 
Garz[oacute]n-Villalba et al., 2019). For unacclimatized workers 
performing heavy workloads in high radiant heat conditions, a heat 
index trigger of 80 [deg]F would be in line with the WBGT-based 
exposure limits (Bernard and Iheanacho, 2015). Although these two 
studies suggest that higher triggers could reasonably be applied to 
workers performing lighter workloads, the assumptions used may not 
always apply to workers (e.g., no exposure to working in the heat the 
prior day, healthy, euhydrated). This may explain, at least in part, 
the discrepancy in findings between the observational and experimental 
studies discussed in this section.
IV. State Standards and Non-Governmental Recommendations
    In their heat-specific standards, summarized in the table below, 
States use various initial and high heat triggers, some of which depend 
on the clothing or gear worn by workers. OSHA's proposed triggers are 
generally in line with those used by these States.
    OSHA is proposing using the same initial heat trigger (heat index 
of 80 [deg]F) as Oregon's existing standard and Maryland's proposed 
standard (Or. Admin. R. 437-002-0156 (2022); Or. Admin. R. 437-004-1131 
(2022); Code of Maryland Regulations 09.12.32: Heat Stress Standards 
(2024)). California and Colorado use an ambient temperature trigger of 
80 [deg]F for outdoor work sites and agricultural sites, respectively, 
as does the Washington standard for workers wearing breathable clothing 
(Cal. Code of Regulations (CCR), tit. 8, section 3395 (2015); 7 Colo. 
Code Regs. section 1103-15 (2022); Wash. Admin. Code sections 296-62-
095 through 296-62-09560; 296-307-097 through 296-307-09760 (2023)). 
California's proposed indoor standard uses an ambient temperature 
trigger of 82 [deg]F (CCR, tit. 8, section 3396 (2023)).
    The high heat trigger that OSHA is proposing (heat index of 90 
[deg]F) is the same as Oregon's existing standard and Maryland's 
proposed standard. California and Colorado use an ambient temperature 
high heat trigger of 95 [deg]F, while the Washington standard uses 90 
[deg]F. The California indoor proposal uses an ambient temperature or 
heat index trigger of 87 [deg]F to impose additional requirements.

            Table V-2--Summary of Triggers Used in Various Heat-Specific Standards at the State Level
----------------------------------------------------------------------------------------------------------------
                State                          Setting            Initial heat trigger      High heat trigger
----------------------------------------------------------------------------------------------------------------
California...........................  Outdoor................  80 [deg]F (Ambient)....  95 [deg]F (Ambient).
Washington...........................  Outdoor................  80 [deg]F (Ambient)      90 [deg]F (Ambient).
                                                                 (all other clothing)
                                                                52 [deg]F (non-
                                                                 breathable clothes)..
California (proposal)................  Indoor.................  82 [deg]F (Ambient)....  87 [deg]F (Ambient or
                                                                                          Heat Index), except
                                                                                          for certain clothing
                                                                                          or in high radiant
                                                                                          heat (82 [deg]F).
Oregon...............................  Indoor/Outdoor.........  80 [deg]F (Heat Index).  90 [deg]F (Heat Index).
Maryland (proposal)..................  Indoor/Outdoor.........  80 [deg]F (Heat Index).  90 [deg]F (Heat Index).

[[Page 70747]]

 
Colorado.............................  Indoor/Outdoor           80 [deg]F (Ambient)....  95 [deg]F (Ambient) or
                                        Agriculture only.                                 other conditions.
----------------------------------------------------------------------------------------------------------------
Note: There are different provisions required at each trigger by each State.

    In the Heat Stress and Strain chapter of their most recent TLV 
booklet, ACGIH recommends establishing a heat stress management plan 
when heat stress is suspected (ACGIH, 2023). One criterion they provide 
for determining when heat stress may be present is whether the heat 
index or air temperature is 80 [deg]F. In comments received from small 
entity representatives during the SBREFA process and a public commenter 
during the ACCSH meeting on April 24, 2024, OSHA heard feedback that 
the agency should consider different triggers that vary by geography. 
Neither the ACGIH TLV/REL nor NIOSH REL/RAL vary by geography; these 
formulas are used globally. Additionally, California regulators, in 
their existing outdoor heat standard and their proposed indoor heat 
standard, use single State-wide triggers, despite the State 
experiencing a wide range of microclimates (e.g., both desert and 
coastal areas exist in the State). Such microclimates would make it 
difficult to identify appropriate geographically specific triggers, as 
factors like elevation and humidity can vary widely even within a 
specific State or region. OSHA has also heard from stakeholders who 
suggested that the triggers in a proposed rule should be presented 
simply, which would be challenging if there were multiple triggers for 
different parts of the country.
V. Summary
    In conclusion, OSHA preliminarily finds that the experimental and 
observational evidence support that heat index triggers of 80 [deg]F 
and 90 [deg]F are highly sensitive and therefore highly protective of 
workers. These triggers are also generally in-line with current and 
proposed triggers in State heat-specific standards. Therefore, OSHA is 
proposing an initial heat trigger of heat index of 80 [deg]F and a high 
heat trigger of heat index of 90 [deg]F. OSHA is also proposing to 
permit employers to use the WBGT-based NIOSH RAL and REL, which are 
supported by empirical evidence and have been found to be highly 
sensitive in capturing unsustainable heat exposure.
A. Requests for Comments
    OSHA requests comments and evidence regarding the following:
     Whether OSHA has adequately identified, documented, and 
correctly interpreted all studies and other information relevant to its 
conclusion about sensitive heat triggers;
     Whether there are additional observational studies or data 
that use more robust exposure metrics (e.g., more than daily maximum 
heat index) to retrospectively assess occupational heat exposure on the 
day of heat-related fatalities and nonfatal HRIs;
     Whether OSHA should consider other values for the initial 
and/or high heat trigger and if so, what evidence exists to support 
those other values;
     The appropriateness of using heat index to define the 
initial and high heat triggers;
     Whether OSHA should explicitly incorporate radiant heat 
into the initial and/or high heat triggers, and if so, how;
     Whether OSHA should explicitly incorporate clothing 
adjustment factors into the initial and/or high heat triggers, and if 
so, how;
     Whether OSHA should use different triggers for different 
parts of the country, and if so, how;
     The appropriateness of applying the same triggers to 
employers who conduct on-site measurements as opposed to employers who 
use forecast data; and
     Whether OSHA should consider an additional trigger 
specific to heat waves or sudden increases in temperature and, if so, 
whether there are definitions of heat waves that are simple and easy-
to-apply.

C. Risk Reduction

I. Introduction
    OSHA identified and reviewed dozens of studies evaluating the 
effectiveness of various controls designed to reduce the risk of heat-
related injuries and illnesses (HRIs). The studies captured include 
observational and experimental studies that examined the effect of 
either a single control or the combined effect of multiple controls. 
These studies were conducted among civilian workers, athletes, military 
personnel, and volunteers. Observational studies conducted outside the 
U.S. were included if OSHA determined the work tasks to be comparable 
to those of U.S.-based workers. OSHA also examined systematic review 
articles that summarized the literature on various individual controls.
    OSHA acknowledges that observational studies evaluating the 
effectiveness of multi-pronged interventions or programs in reducing 
HRI incidence in ``real-world'' occupational settings are the most 
relevant for assessing the reduction in risk of the proposed rule. 
However, OSHA identified very few of these studies in the literature 
review and determined there to be some limitations in extrapolating 
their findings to the proposed rule. Therefore, OSHA also examined 
studies looking at the effectiveness of single interventions, many of 
which were experimental in design.
    One limitation of the experimental studies--often conducted in 
laboratory settings--is that they were not conducted in ``real-world'' 
occupational settings. However, some of these studies were designed to 
simulate actual work tasks and work environments, which increases the 
generalizability for occupational settings (i.e., the extent that the 
study results can be applied to employees exposed in the workplace). 
Additionally, one advantage of experimental studies is that they can be 
conducted under controlled conditions and are thus able to better 
measure endpoints of interest and control for confounding variables. 
Experimental studies are also sometimes able to examine situations in 
which subjects experience high levels of heat strain because the close 
physiological monitoring of subjects allows the study to be stopped 
before the subject is at risk of heat stroke or death.
    Although many of these studies evaluated measures of heat strain 
(e.g., core body temperature, heart rate) rather than instances of 
HRIs, OSHA believes that these metrics are important for understanding 
risk of HRIs. As discussed in Section IV., Health Effects, these 
metrics are intermediary endpoints on the path to HRIs (e.g., heat 
stroke, heat exhaustion). The controls required in the proposed 
standard are effective in that they reduce or slow the

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accumulation of heat in the body, which in turn reduces the risk of 
HRIs.
    OSHA also examined and summarized systematic review articles that 
reviewed and discussed the experimental literature. These articles were 
written by prominent heat safety experts (in either an occupational or 
athletic context) and were typically conducted using a consensus-type 
approach. OSHA also looked outside the peer-reviewed literature for 
consensus statements, reports, recommendations, and requirements from 
governmental bodies and non-governmental organizations.
    Despite the limitations noted above, the studies, review articles, 
and non-peer reviewed sources presented in this section represent the 
best available evidence OSHA has identified regarding the effectiveness 
of controls designed to reduce the risk of HRIs. The following summary 
of OSHA's findings demonstrates that the requirements of the proposed 
rule will be effective in reducing the risk of HRIs among workers.
II. Evidence on the Effectiveness of Individual Control Measures
A. Systematic Reviews and Consensus Statements
    Several publications have summarized the literature on the efficacy 
of controls to reduce the risk of HRI in the form of review articles or 
consensus statements. For example, Morris et al. (2020) assessed 
systematic reviews, meta-analyses, and original studies on heat-related 
intervention strategies published in English prior to November 6, 2019, 
that included studies conducted at ambient temperatures over 28 [deg]C 
or among hypohydrated (i.e., fluid intake is less than water lost 
through sweat) participants, used healthy adult participants, and 
reported physiological outcomes (e.g., change in heart rate, core 
temperature, thermal comfort) and/or physical or cognitive performance 
outcomes. Most of the captured articles were from the exercise 
literature, but 9 of the 36 systematic reviews (i.e., a detailed and 
comprehensive reviews of relevant scientific studies and other 
evidence) mentioned occupational exposure in various professions, such 
as military personnel, firefighters, and emergency responders. A second 
search identified 7 original studies that were not covered in the 
systematic reviews. Based on their systematic review, the study authors 
identified the following effective interventions: environmental 
conditioning (e.g., fans, shade, air-conditioning); optimal clothing 
(e.g., hats; loose fitting, light/brightly colored/reflective, 
breathable, clothing; ventilation patches in PPE; cooling garments/
PPE); physiological adaptation (e.g., acclimatization, improving 
physical fitness); pacing (e.g., reduced work intensity, breaks); 
hydration and nutrition (e.g., hydration, electrolytes); and personal 
cooling options (e.g., cold water ingestion, water immersion). They 
also noted that ``a generally under investigated, yet likely effective 
. . . intervention is to utilize pre-planned breaks in combination with 
the cooling interventions mentioned above.'' Morris et al. (2020) also 
noted that ``maintaining hydration is important for maintaining 
cognitive and physical performance'' (Morris et al., 2020).
    Morrissey et al. (2021b) assembled 51 experts with experience in 
physiology, occupational health, and HRIs to review and summarize 
current data and gaps in knowledge for eight heat safety topics to 
develop consensus recommendations. The experts created a list of 40 
heat safety recommendations within those eight topics that employers 
could implement at their work site to protect workers and to avoid 
productivity losses associated with occupational heat stress. These 
recommendations for each of the eight topics included:
    (1) Hydration: e.g., access and availability to cool, potable 
water; training on hydration; addressing availability of fluids during 
rest breaks in the prevention plan;
    (2) Environmental monitoring: e.g., measurements as close to the 
work site as possible; consideration of environmental conditions (e.g., 
temperature, humidity, wind speed, radiance), work demands, PPE, and 
worker acclimatization status in assessing heat stress; including 
environment-based work modifications (e.g., number of rest breaks) in a 
prevention plan;
    (3) Emergency procedures and plans: e.g., availability of an 
emergency plan for each work site; identification of personnel to 
create, manage, and implement the plan; making available, rehearsing, 
and reviewing the plan annually;
    (4) Body cooling: e.g., availability of rest/cooling/hydration 
areas made accessible to workers as needed; cooling during rest breaks 
(e.g., immersion, shade, hydration, PPE removal); use of fans (at 
temperatures below 40 [deg]C (104 [deg]F)) or air-conditioners; use of 
portable cooling strategies (e.g., ice, water, ice towels) in areas 
without electricity; use of cooling strategies before, during, and 
after work; cooling PPE used under other PPE when PPE can't be removed;
    (5) Acclimatization: e.g., creation and implementation of a 5-7 day 
acclimatization plan; plans for both new and returning workers that are 
tailored to factors such as environmental conditions and PPE; training 
on benefits of acclimatization;
    (6) Textiles/PPE: e.g., use of clothing/PPE that is thin, 
lightweight, promotes heat dissipation, that fits properly, and 
adequately protects against hazards; PPE with ventilated openings; 
removal of PPE/extra layers during rest periods;
    (7) Physiological monitoring: (e.g., checking heart rate/body 
temperature); and
    (8) Heat hygiene: e.g., annual training on heat related illness, 
prevention, first aid, and emergency response in language and manner 
that is easily understood; designated personnel or ``buddy approach to 
monitor for symptoms''; communication strategies to inform employees of 
heat mitigation strategies before the work shift, healthcare worker 
using examination results (if examinations are required or recommended) 
to educate employees.
    Racinais et al. (2015) presented consensus recommendations to 
reduce physiological heat strain and optimize sports performance in hot 
conditions that were developed in roundtable discussions by a panel of 
experts. While recommendations were focused on athletes, the study 
authors noted that current knowledge on heat stress is mainly available 
from military and occupational research, with information from sport 
sciences available only more recently. The study authors recommended 
three main interventions. The first recommendation, considered to be 
most important by study authors, was acclimatization, involving 
repeated training in heat for at least 60 minutes a day over a 1-2 week 
period. The authors explained that acclimatization attenuates the 
physiological strain of heat by improving cardiovascular stability and 
electrolyte balance through an increase in sweat rate, skin blood flow, 
and plasma volume. The second recommendation was drinking sufficient 
fluids to maintain adequate hydration before and after exercise. Study 
authors explain that sweating during exercise can lead to dehydration 
which, if not mitigated by fluid intake, has the potential to 
exacerbate cardiovascular strain and reduce the capacity to exercise in 
the heat. The third recommendation was cooling methods to reduce heat 
storage and physiological strain (e.g., fanning, iced garments/towels, 
cold fluid intake, cooling vests, water immersion). Additional 
recommendations for event organizers included planning for shaded 
areas,

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cooling and rehydration facilities, and longer recovery periods (i.e., 
break periods) for hydration and cooling.
B. Summary for Systematic Reviews and Consensus Statements
    In conclusion, OSHA reviewed three sets of recommendations on 
effective controls to prevent HRI developed by scientific experts 
following extensive literature reviews. A number of the recommendations 
were consistent with requirements or options in OSHA's proposed 
standard. For example, all three groups of experts recommended 
hydration, rest breaks, shade, cooling measures such as fans, and 
acclimatization (Morris et al., 2020; Morrissey et al., 2021b; Racinais 
et al., 2015). Two of the expert groups also recommended cooling 
methods such as air conditioning (Morris et al., 2020; Morrissey et 
al., 2021b). One of the groups recommended environmental monitoring, 
development of emergency procedures and plans, training, a buddy system 
to monitor for health effects, and communication of heat mitigation 
strategies (Morrissey et al., 2021b).
III. Experimental and Observational Evidence
A. Rest Breaks
    Administrative controls, such as varying employees' work schedules, 
are a well-accepted and long-standing approach to protect workers from 
occupational hazards. Administrative controls are regularly used to 
address limitations in human capacity for physical work and commonly 
include work-rest cycles. Rest breaks provide an opportunity for 
workers to reduce their metabolic rate and body temperature 
periodically throughout the day. Length and frequency of breaks can be 
adjusted based on heat exposure, workload, acclimatization, and 
clothing/PPE factors. Such an approach of work-rest cycles that 
consider these factors has been recommended by NIOSH and ACGIH (NIOSH, 
2016; ACGIH 2023). Observational and experimental studies show the 
effectiveness of rest breaks in reducing heat strain that could lead to 
HRIs, and those studies are described below. In addition to reducing 
heat strain, rest breaks allow workers to take advantage of other 
cooling strategies, such as hydrating, removing PPE, and sitting in 
areas that are shaded, cooled, or fanned. The literature on the 
efficacy of rest breaks described below includes observational studies 
of workers, laboratory-based exercise trials, and predictive modeling.
I. Observational Studies
    Several observational studies examined participants in work 
settings or training exercises while at work and at rest and evaluated 
the associations between rest breaks or time at rest and markers of 
heat strain.
    Horn et al. (2013) evaluated core body temperature and heart rate 
(HR) among nine firefighters (six male and three females, ages 20-45 
years) over a 3-hour period in which four repeat bouts of firefighting 
drills were conducted (approximately 15-30 minutes each) while wearing 
full PPE and a self-contained breathing apparatus. The drills were 
separated by three rest periods (approximately 20-40 minutes each) in 
which the firefighters were encouraged to hydrate and cool down by 
removing their gear, while being evaluated/critiqued by instructors and 
refilling air cylinders. The study authors estimated the duration of 
work and rest cycle lengths based on sustained rates of heart rate 
increases and decreases. Ambient temperatures ranged from 15 [deg]C to 
25 [deg]C (59-77 [deg]F) during the summer and fall months when this 
study was conducted. During work cycles, mean maximum core temperatures 
ranged from 38.4-38.7 [deg]C, mean peak heart rate ranged from 181.2-
188.4 beats per minute (bpm), and the mean average heart rate (averaged 
over 60 second intervals per work cycle) ranged from 139.6-160.0 bpm. 
Mean maximum core temperature and mean average heart rate decreased 
during rest periods, and the study authors concluded that physiological 
recovery in this study appeared to be closely linked to the duration of 
rest periods. Rest break duration was significantly and negatively 
correlated with the following measurements taken during rest breaks: 
minimum heart rate (r: -0.687, p<0.001), average heart rate (r: -0.482, 
p=0.011), and minimum core temperature (r: -0.584, p=0.001), indicating 
that longer breaks result in reduced heat strain. The authors concluded 
that the association was independent of obesity, fitness, and intensity 
of firefighting activities. Limitations noted by study authors included 
enrollment of young firefighters who were screened for cardiovascular 
disease, and thus might not represent the whole firefighting 
population. In addition, ``significant breaks'' were provided and the 
duration of exposure to fires was shortened later in the day, both 
factors that might underestimate increases in core temperatures with 
longer firefighting activities and shorter breaks.
    Petropoulos et al. (2023) characterized heat stress and heat strain 
in a cohort of 569 male outdoor workers in Nicaragua (sugarcane, 
plantain, and brickmaking industries) and El Salvador (sugarcane, corn, 
and construction industries) across three workdays in 2018. Median wet 
bulb globe temperatures (WBGT) ranged from 26.0-29.2 [deg]C (78.8-84.6 
[deg]F) and median heat index ranged from 28.5-36.1 [deg]C (83.3-97.0 
[deg]F) at the work sites. Time spent on rest breaks-estimated based on 
physical activity data collected with an accelerometer (i.e., a device 
that can be used to measure physical activity and sedentary time)--was 
estimated at 4.1-21% of the shift. A 10% increase in the time spent on 
break was associated with a 1.5% absolute decrease in median percent 
maximum heart rate (95% CI: -2.1%, -0.85%; p<0.0001), when adjusting 
for industry/company, job task, shift duration, liquid consumption, 
median WBGT, and mean metabolic rate. Petropoulos et al. (2023) found 
no significant associations between rest breaks and maximum core body 
temperature, and concluded that the lack of findings could have been 
due to incomplete control of confounding factors.
    Lucas et al. (2023) examined the effects of recommended rest breaks 
for sugarcane workers in Nicaragua, specifically in male burned cane 
cutters, by comparing the period from 2019-2020, identified as Harvest 
3 (H3; n=40 burned cane cutters) with the period from 2018-2019, 
identified as Harvest 2 (H2; n=12 burned cane cutters). OSHA notes that 
a major limitation of the study identified by authors was a shorter 
shift duration by 1 to 2 hours for seed cutters (SC) during H2, and 
that ``the shorter shifts in H2 likely affected SC workload comparisons 
between H2 and H3 and could explain why increasing the rest component 
in H3 did not reduce the physiological workload in this group.'' 
Because of this limitation in seed cutters, this summary focuses on 
effects on burned cane cutters. In H3, an extra 10-minute rest break 
was recommended (increasing recommended rest breaks to a total of 80 
min over a six-hour shift), and interventions from H2 were continued 
(e.g., improvements to hydration and movable tents, in addition to 
delaying cutting after burning to reduce radiant heat exposure). Daily 
average WBGT was higher in H2: 29.5 [deg]C (85.1 [deg]F) than in H3: 
26.7 [deg]C (80.6 [deg]F). Rest periods were defined by a greater than 
10 bpm drop in heart rate lasting 4 or more minutes, as determined by 
continuous measurements by heart rate sensors

[[Page 70750]]

worn on the chest; based on those measurements, the rest/work ratio for 
burned cane cutters increased slightly from 21% rest in H2 to 26% rest 
in H3. Average percent maximum heart rate (adjusted for age) decreased 
slightly in H3 compared to H2 (mean [95% CI] 63% [60-65%] to 58% [56-
60%]) across the work shift). No significant differences were noted for 
estimated core temperatures (based on modeling) from H2 to H3. The 
study authors acknowledged that observational study design, small 
number of workers in H2, and the lower temperatures in H3 may make 
conclusions uncertain; therefore experimental laboratory studies may 
better test the impact of the intervention. OSHA also observes that the 
increased number of burned cane cutters observed from H2 to H3 means 
that the population of workers observed was different in the two 
periods and results may have been affected by different characteristics 
of the workers.
    Ioannou et al. (2021a) examined the effectiveness of rest breaks of 
different durations in agricultural, construction, and tourism 
employees. Findings in the intervention group were compared to a 
``business as usual'' (BAU) group, where workers followed their normal 
routine. Of note, shaded areas, water stations, and air-conditioned 
areas to be used for rest breaks were part of BAU for construction 
workers in Spain; those same interventions were part of BAU for 
construction workers in Qatar, in addition to requiring workers to 
carry a water bottle, and education. BAU practices were not specified 
for the agriculture and tourism industries, but according to 
communications with study authors, the BAU agricultural employees in 
Qatar were not offered scheduled work/rest cycles, and agricultural 
employees who were monitored in Qatar performed low intensity work 
(Communication with Leonidas Ioannou, April 2024). Endpoints observed 
included core temperature, skin temperature, heart rate, and metabolic 
rate. No significant effects compared to the BAU group were observed 
for any of these endpoints for agricultural workers in Cyprus provided 
with a 90-second break every 30 minutes, tourism workers in Greece 
provided with a 90-second break every 30 minutes or a 2-minute break 
every 60 minutes combined with ice slurry ingestion, or construction 
workers in Spain provided with two 7-minute breaks over the workday. 
For employees in Qatar who were provided with 10-minute breaks every 50 
minutes, significant differences in the intervention group compared to 
the BAU group included lower mean skin temperature, heart rate, and 
metabolic rate for construction employees, but increased heart rate for 
agricultural employees. The study authors postulated that the increased 
heart rate in agricultural workers resulted from inherent changes in 
body posture (i.e., moving from a crouching position while crop picking 
to standing and walking during breaks). A limitation in this study is 
that some BAU groups, which were used as comparison groups, appeared to 
have access to breaks in air-conditioned areas and it was not described 
how the frequency or duration of rest breaks varied between the 
intervention and BAU groups.
    Two additional studies were conducted in utility workers. In a case 
study by Meade et al. (2017), conducted in an unspecified location, 
four highly experienced electrical utilities workers were observed via 
video analysis over two consecutive hot days. The study authors noted 
that employees often spent 80% or more of the monitoring period working 
in direct sunlight. Meade et al. (2017) reported similar average core 
body temperatures and average %HRmax on both days, despite an increase 
in the percentage of time spent at rest on Day 2 versus Day 1 (time at 
rest: 66  5%, range: 60-71%, on Day 2 versus 51  15%, range: 30-63% on Day 1). Three of the four workers had a 
higher peak core temperature on Day 2 than Day 1. The study authors 
attributed these core temperature and heart rate trends in part to 
residual heat storage or fatigue-related changes in work efficiency 
that possibly occurred over two consecutive work shifts. Meade et al. 
(2016a) observed work and rest periods in 32 electrical utilities 
workers (mean age of 36 years; 11 ground workers, 9 bucket workers, 12 
manual pole workers; 17 in West Virginia, 15 in Texas) via video 
analysis and accelerometry over 1 day (Heat Index: West Virginia 48 
 3 [deg]C (118.4 [deg]F), Texas 42  3 [deg]C 
(107.6 [deg]F)). On average, the work-to-rest ratio was (3.1  3.9):1 and workers rested for a total of 35.9  15.9% 
of the work shift. Heat index, work-to-rest ratios, work shift 
duration, and time at rest were not significantly correlated with mean 
core temperature or %HRmax. However, time spent or percentage of time 
in heavy work was moderately, positively correlated with mean core 
temperature (r=0.51) and %HRreserve (r=0.40) (i.e., increased time 
spent in heavy work was associated with increased mean core temperature 
and %HRmax). OSHA notes limitation in these studies, including, for 
example, the very small sample size in Meade et al. (2017) and lack of 
adjustment for possible confounding factors in Meade et al. (2016a).
    A limited number of cross-sectional studies surveyed or interviewed 
employees for self-reported symptoms of HRI to determine possible risks 
associated with inadequate breaks. These types of studies are the most 
limited because of uncertainties such as recall bias (i.e., inaccurate 
recollection of previous events or experiences) and the potential for 
dependent misclassification as a result of using self-reporting for 
characterizing both the exposure and outcome. Therefore, only brief 
summaries of these studies are provided. Two of these studies were 
conducted in agricultural workers in the U.S. (Spector et al., 2015; 
Fleischer et al., 2013), and one was conducted in pesticide applicators 
in Italy (Ricc[ograve] et al., 2020). Spector et al. (2015) found a 
significantly increased odds of HRI in workers paid by piece as 
compared to workers paid hourly (OR: 6.20, 95% CI: 1.11, 34.54). 
Spector et al. (2015) noted that piece rate workers might work harder 
and faster because of economic incentives, thus leading to increased 
metabolic heat generation; however, adjustment for task and exertion in 
the small sample size of employees did not completely attenuate the 
observed association, thus suggesting other factors contributed to 
development of symptoms. Through population intervention modeling, 
Fleischer et al. (2013) estimated that the prevalence of three or more 
HRI symptoms could be reduced by 6.0% if workers had access to regular 
breaks, and by 9.2% if breaks were taken in shaded areas. Of note, 
participants in the study were asked about ``regular breaks,'' but the 
term was not specified regarding frequency and duration. Lastly, 
Ricc[ograve] et al. (2020) found taking rest breaks in shaded, non-air-
conditioned areas was associated with experiencing HRI (adjusted OR: 
5.5, 95% CI: 1.4, 22), while taking rest breaks in cooler, air-
conditioned areas was not. Ricc[ograve] et al. (2020) discussed 
possible reasons for the observed association between shaded rest 
breaks and incidences of HRI, including that (1) taking breaks in shade 
may be insufficient to prevent HRIs among pesticide applicators who 
undertake more strenuous tasks or have longer exposures to unsafe 
limits, and (2) rest breaks in shade may be taken to alleviate, rather 
than prevent, HRI symptoms (i.e. possible reverse causation).

[[Page 70751]]

II. Experimental Studies
    OSHA examined a number of laboratory studies that provide 
information on the efficacy of rest breaks for preventing heat strain 
or HRI in subjects exercising under conditions that include high heat 
and at least moderate activity. The studies typically measured rectal 
temperature, which allowed for an assessment of the efficacy of breaks 
in maintaining lower rectal temperatures and slowing the increase in 
rectal temperatures. ACGIH (2023) indicates that an increase in rectal 
temperature exceeding 1 [deg]C from a ``pre-job'' temperature of less 
than 37.5 [deg]C might indicate excessive heat strain. One study 
summarized below also examines the effect of rest breaks on the 
autonomic nervous system and cardiovascular function.
    Smallcombe et al. (2022) conducted a study over a seven-hour period 
that was designed to mimic a typical workday in the U.S. In that study, 
9 males (average age 23.7 years) of varying fitness levels walked on a 
treadmill at speeds to maintain a constant heart rate of 130 bpm, which 
the authors indicated to be the demarcation between moderate and heavy 
strain. The subjects completed six cycles of exercise for 50 minutes in 
the heat chamber separated by 10 minutes of rest at an ambient 
temperature of 21 [deg]C (69.8 [deg]F), 50% relative humidity (RH) 
while drinking water as desired. A one-hour lunch period was also 
provided at 21 [deg]C (69.8 F), 50% RH after the third exercise period, 
with all subjects given the same lunch and allowed to drink water as 
desired. Each subject was tested under 4 temperature conditions: (1) 
referent (cool condition) at 15 [deg]C (59 [deg]F) (WBGT = 12.6 
[deg]C); (2) moderate condition at 35 [deg]C (95 [deg]F) (WBGT = 29.4 
[deg]C); (3); hot condition at 40 [deg]C (104 [deg]F) (WBGT = 33.4 
[deg]C); and (4) very hot condition at 40 [deg]C (104 [deg]F) (WBGT = 
36.1 [deg]C). The RH for each temperature condition was approximately 
50%, except for the very hot condition, which was 70% RH. In the very 
hot condition group, data were limited for the sixth exercise cycle 
because an unspecified number of participants reached the cut-off point 
for terminating the study (i.e., a heart rate exceeding 130 bpm while 
at rest).
    Significant increases in mean rectal temperature were observed in 
the moderate, hot, and very hot condition groups in work period 1 
versus work period 6, but the average rectal temperature remained at or 
below 38 [deg]C (100.4 [deg]F) in all groups during each exercise 
period (figure S1 and table S2) (Smallcombe et al., 2022). No 
individual subject had a rectal temperature that exceeded 38 [deg]C in 
the referent and moderate condition groups, however, three subjects 
exceeded 38 [deg]C in the hot exposure group, and four subjects 
exceeded 38 [deg]C in the very hot exposure group. With the exception 
of two subjects whose rectal temperatures were measured at 
approximately 38.6 [deg]C (101.5 [deg]F) and 38.7 [deg]C (101.7 [deg]F) 
in the very hot exposure group, all rectal temperatures were below 38.5 
[deg]C (as estimated from Figure S1). In addition, mean rectal 
temperatures dropped during each rest period, with all rectal 
temperatures measured near or below 38 [deg]C by the end of the rest 
period (as estimated from Figure 4). Skin temperatures did not increase 
during work periods. The authors concluded that under the conditions of 
this study, which limited metabolic heat production based on the fixed 
heart rate protocol, participants rarely reached levels of core 
temperature that would be concerning. Study limitations noted by study 
authors included possible limited relevance of breaks provided in 
cooler areas, and the possibility that thermo-physiological impacts may 
have been higher had breaks not been provided in cooler areas or 
metabolic heat production not been limited.
    In Uchiyama et al. (2022) thirteen males (average age 39 years) 
each underwent two 225-minute trials that included 180 minutes of 
treadmill walking in a chamber at 37 [deg]C (98.6 [deg]F) and 40% RH 
interspersed with 45 minutes of rest breaks in an air-conditioned room 
at 22 [deg]C (71.6 [deg]F) and 35% RH, designed to mimic summer working 
and rest conditions at mines in Northwest Australia. Participants were 
allowed to drink room temperature water during exercise and 
refrigerated water while on rest breaks. Two different rest/work cycles 
were tested, including (1) current practice: 1 hour of work and 30 
minutes of rest, followed by 1 hour of work and 15 minutes rest, and a 
final 1 hour work period; and (2) experimental: 1 hour of work and 15 
minutes rest, followed by three half hour work periods separated by 10-
minute rest periods and, and a final half hour work period. OSHA 
observes that in the current practice group, average core temperature 
only increased by more than 1 [deg]C (1.8 [deg]F) of baseline level at 
the final measurement reported at 180 minutes into the study (increased 
from 37.2 [deg]C at baseline to 38.29 [deg]C at 180 minutes). Average 
core temperatures remained within 1 [deg]C of baseline levels in the 
experimental group at all time points.
    Three studies (Meade et al., 2016b; Lamarche et al., 2017; and 
Kaltsatou et al., 2020) conducted 2-hour studies in which small groups 
of 9-12 males cycled in a heat chamber at 360 watts (W) of metabolic 
heat production (considered moderate-to-heavy intensity and equivalent 
to conditions experienced by some workers in the mining and utility 
industries). Over the 2-hour period, the effects of various 
temperatures (approximate values provided) and work/rest protocols 
recommended by ACGIH were examined including: (1) continuous work at 
WBGT 28 [deg]C (82.4 [deg]F) (41 [deg]C (105.8 [deg]F) dry-bulb, 19.5% 
RH or 36 [deg]C (96.8 [deg]F) dry-bulb, 38% RH); (2) a 3:1 work/rest 
ratio (15 min work, 5 min rest) at WBGT 29 [deg]C (84.2 [deg]F) (43 
[deg]C (109.4 [deg]F) dry-bulb, 17.5% RH or 38 [deg]C (100.4 [deg]F) 
dry-bulb, 34% RH); and (3) a 1:1 work/rest ratio (15 min work, 15 min 
rest) at WBGT 30 [deg]C (86 [deg]F) (46 [deg]C (114.8 [deg]F) dry-bulb, 
13.5% RH or 40 [deg]C (104 [deg]F) dry-bulb, 30% RH). Meade et al. 
(2016b) examined a fourth condition: 4) a 1:3 work/rest ratio (15 min 
work, 45 min rest) at WBGT 31.5 [deg]C (88.7 [deg]F) (46.5 [deg]C 
(115.7 [deg]F) dry-bulb, 17.5% RH). The mean age of participants in the 
Meade et al. (2016b) study was 21 years while the mean age in both the 
Lamarche et al. (2017) and Kaltsatou et al. (2020) studies was 58 
years.
    Meade et al. (2016b) found that among younger males, the 
percentages of participants with rectal temperatures exceeding 38 
[deg]C over the 2-hour protocol was lower in the groups who took longer 
rest breaks, despite those groups also being subjected to a higher 
WBGT. Meade et al. (2016b) reported core temperatures exceeding 38 
[deg]C in 12% of participants in the 1:3 work/rest at 31.5 [deg]C WBGT 
group, 0% in the 1:1 work/rest at 30 [deg]C WBGT group, 33% in the 3:1 
work/rest at 29 [deg]C WBGT group, and 33% in the continuous work at 28 
[deg]C WBGT group.
    Lamarche et al. (2017) found that among older males, the percentage 
of participants with rectal temperatures exceeding 38 [deg]C over the 
2-hour protocol was lowest in the group with the longest breaks (i.e., 
67% in the 1:1 work/rest at 30 [deg]C WBGT group, 100% in the 3:1 work/
rest at 29 [deg]C WBGT group, and 100% in the continuous work at 28 
[deg]C WBGT group) although the findings did not achieve statistical 
significance. Lamarche et al. (2017) also reported that time to exceed 
a rectal temperature of 38 [deg]C was higher in both groups who 
received rest breaks as compared with the continuous work group and 
this did reach statistical significance. Specifically, the time to 
exceed a rectal temperature of 38 [deg]C was 100 minutes in the 1:1 
work/rest at 30 [deg]C WBGT group, 79 minutes in the 3:1 work/rest at 
29 [deg]C WBGT group, and 53 minutes in the

[[Page 70752]]

continuous work at 28 [deg]C WBGT group. Further, because of heat 
exhaustion, five participants in the Lamarche et al. (2017) study did 
not complete the continuous work at 28 [deg]C WBGT protocol, one did 
not complete the 3:1 work/rest at 29 [deg]C WBGT protocol, but all 
completed the 1:1 work/rest 30 [deg]C WBGT protocol. No significant 
differences in heart rate were observed.
    Kaltsatou et al. (2020) examined autonomic stress and 
cardiovascular function in the same subjects examined by Larmarche et 
al. (2017). The authors measured 12 markers of heart rate variability 
(HRV), a predictor of adverse heart events, most of which are 
associated with the autonomic nervous system (i.e., a part of the 
nervous system that controls involuntary responses including heart rate 
and blood pressure). After one hour of accumulated work and when rectal 
temperatures exceeded 38 [deg]C, three markers of HRV were 
significantly lower in the continuous work group than in the 3:1 work/
rest at 29 [deg]C WBGT group. One marker of HRV was significantly lower 
in the continuous group, compared to the 1:1 work/rest at 30 [deg]C 
WBGT group at 1 hour of accumulated work. After 2 hours of accumulated 
work, 4 markers of HRV were significantly lower in the continuous work 
group compared to the 1:1 work/rest at 30 [deg]C WBGT group. Study 
authors interpreted these results to indicate that continuous work was 
the least safe for workers, while a 1:1 work/rest ratio offered the 
best protection. Kaltsatou al. (2020) concluded that breaks during 
moderate-to-heavy work in heat can reduce autonomic stress and increase 
the time to exceed a rectal temperature of 38 [deg]C.
    In the studies by Meade et al. (2016b), Lamarche et al. (2017), and 
Kaltsatou et al. (2020), participants were well-hydrated before the 
study period but not provided drinking water during the study. 
Kaltsatou et al. (2020) acknowledged that not providing water during 
the study could have affected sweat secretion and, as a result heat 
balance, hydration status, baroreceptor function (involved in blood 
pressure regulation), and the autonomic control of heart rate. OSHA 
agrees and also notes that rest breaks were provided in the same 
ambient conditions as work periods, and studies were conducted at a 
fixed work rate that would have not considered possible effects of 
self-pacing. Because hydration and shade or cooling measures during 
rest breaks would be provided as part of an effectively implemented 
multi-pronged approach to preventing HRI, OSHA preliminarily concludes 
that some of the effects observed in these studies might have been less 
severe if interventions other than rest were provided.
    In a study by Chan et al. (2012), recovery time, as measured by 
physiological strain index (based on heart rate and core temperatures), 
was determined in 19 healthy construction rebar employees (mean age 45 
years) who had worked until exhaustion at building construction sites 
in Hong Kong in July and August of 2011. Average recovery during rest 
was reported at 94% in 40 minutes, 93% in 35 minutes, 92% in 30 
minutes, 88% in 25 minutes, 84% in 20 minutes, 78% in 15 minutes, 68% 
in 10 minutes, and 58% in 5 minutes. Yi and Chan (2013) used the field-
based meteorological and physiological data reported by Chan et al. 
(2012) to model ideal rest breaks to minimize HRI. Based on a Monte 
Carlo simulation, the authors determined that a 15-minute break after 
120 minutes of continuous work in the morning at 28.9 [deg]C (84.0 
[deg]F) WBGT and a 20-minute break after 115 minutes of continuous work 
in the afternoon at 32.1 [deg]C WBGT (90.0 [deg]F) maximized 
productivity time while protecting the health and safety of employees.
III. Conclusions for Rest Breaks
    OSHA reviewed several studies examining the effectiveness of rest 
breaks in preventing heat strain that could lead to HRI and were of 
sufficient quality for drawing conclusions (Horn et al., 2013; 
Smallcombe et al., 2022; Meade et al., 2016b; Lamarche et al., 2017; 
Kaltsatou et al., 2020; Petropoulos et al., 2023). The studies, 
involving individuals exposed to conditions of high heat stress, 
demonstrated the effectiveness of rest breaks in preventing measures of 
heat strain that can lead to HRI. Observational studies with detailed 
measurements of temperatures in firefighters doing training exercises 
and experimental studies in laboratory settings reported that rest 
breaks result in lower core or rectal temperatures during rest periods 
following work periods (Horn et al., 2013; Smallcombe et al., 2022), 
and lower rectal temperatures over the study period (Meade et al., 
2016b; Lamarche et al., 2017), with all of the studies showing greater 
effectiveness of longer compared to shorter duration work breaks. 
Similarly, Chan et al. (2012) reported increased physiological recovery 
with longer rest periods. Uchiyama et al. (2022) reported little 
evidence of heat strain in participants exercising in hot conditions 
and provided rest breaks. The study by Lamarche et al. (2017) also 
found that rest breaks were effective in preventing heat exhaustion in 
a laboratory setting. OSHA also found evidence showing that rest breaks 
can reduce cardiovascular strain. For example, Horn et al. (2013) found 
that heart rates were lower in rest than in work cycles. One study done 
in participants in a laboratory setting showed that rest breaks can 
reduce autonomic stress that affects cardiovascular function (Kaltsatou 
et al., 2020). Those findings are consistent with an observational 
study of employees in occupational settings that found an association 
between time spent on rest breaks and decreases in heart rate when 
adjusted for industry/company, job task, shift duration, liquid 
consumption, WBGT, and metabolic rate (Petropoulos et al., 2023).
    In conclusion, OSHA preliminarily finds rest breaks to be effective 
in reducing the risk of HRI by modulating increases in heat and 
cardiovascular strain.
B. Shade
    Working or resting in shade reduces the risk of HRI by decreasing 
exposure to solar radiation and in turn reducing overall heat load. 
Studies evaluating the impact of shade on heat strain metrics have 
predominantly been conducted in controlled settings where participants 
exercise in conditions approximating shade and sun exposure. Studies 
evaluating the physiological benefits of exercising in shade versus sun 
are likely to underestimate the benefits of rest breaks taken in shade 
because metabolic heat generation would be slowed while resting.
    A number of studies examining the effects of exercising under 
natural or simulated conditions of sun or shade have demonstrated 
benefits of shade. One group of investigators conducted studies where 
participants cycled under simulated laboratory conditions of sun or 
shade (Otani et al., 2016; Otani et al., 2021); both studies were 
conducted under conditions of 30 [deg]C (86 [deg]F) and 50% RH, and 
participants cycled at a rate of 70% maximum oxygen uptake until 
reaching full exhaustion. The Otani et al. (2021) study also involved 
exposures to low and high wind speeds. The same investigators conducted 
45-minute, self-pacing cycling trials outdoors under various natural 
sunlight conditions, including clear skies or thick and thin cloud 
covers (Otani et al., 2019). These studies reported that higher 
exposure to solar radiation resulted in higher skin temperatures (Otani 
et al., 2016, 2019, 2021) and reduced work output (measured as 
endurance capacity/time-to-exhaustion (Otani et al., 2016; 2021) or 
power output (Otani et al., 2019)). In increased

[[Page 70753]]

sun conditions, Otani et al. (2021) reported higher rectal 
temperatures, heart rates, and thermal sensation. Otani et al. (2019) 
reported greater thermal sensations, and body heat gain from the sun, 
but no significant effects on rectal temperature or heart rate in 
increased sun conditions. Otani et al. (2016) reported no differences 
in rectal temperatures or heart rates in increased sun conditions. The 
authors speculated in their 2019 paper that the lack of rectal 
temperature increase in that study likely resulted from a reduction in 
self-regulated exercise under sunny conditions (Otani et al., 2019). 
They did not however speculate reasons for the lack of rectal 
temperature increases in their 2016 paper. OSHA notes that under 
equivalent (full sun) solar radiation levels the time it took 
participants to reach exhaustion in the Otani et al. (2021) study under 
low wind speeds (35.4 minutes) was longer than the time it took 
participants in the Otani et al. (2016) study to reach exhaustion (22.5 
minutes), and OSHA expects that the disparate findings on rectal 
temperatures may have resulted from differences in total cycling time.
    In a study by Nielsen et al. (1988) participants cycled at a fixed 
rate outdoors in the sun for 60 minutes, were shaded for 30 minutes 
while continuing to cycle, and then cycled again in the sun for another 
30 minutes, for a total of 120 minutes. Study authors noted that cloud 
formation interrupted 3 of the 20 cycling trials. Average rectal 
temperatures rose sharply during the first period of cycling in sun, 
dropped slightly (non-significantly) during the period of cycling in 
shade, and then gradually increased again during the final cycling 
period in full sun. Skin temperatures remained fairly constant during 
the initial period of cycling in sun, dropped significantly by 1.5 
[deg]C (2.7 [deg]F) while cycling in shade, and rose again sharply 
during the final cycling period in the sun. Heart rate, oxygen 
consumption, and sweat rate were significantly higher in the final 
cycling period in full sun, compared to the cycling period in shade. 
Study authors concluded that heat received from direct solar radiation 
``imposed a measurable physiological stress.''
    In a study examining work capacity in adults walking for one hour 
under various conditions of solar radiation (full sun or full shade), 
temperature (25 [deg]C through 45 [deg]C; 77 [deg]F through 113 
[deg]F), humidity (20% or 80%), and clothing coverage, Foster et al. 
(2022b) reported that work capacity (calculated using treadmill speed 
and grade) was generally lower under full sun conditions than shaded 
conditions. Under humid conditions, work capacity was reduced by solar 
radiation for all scenarios. Under dry conditions, work capacity 
reduction varied by clothing coverage with those wearing full-body work 
coveralls showing reduced work capacity at temperatures >=35 [deg]C 
(>=95 [deg]F) and those wearing minimal clothing showing reduced work 
capacity at temperatures >=40 [deg]C (>=104 [deg]F). Skin temperature 
was generally higher under full sun conditions, and the authors 
speculated that a lack of effect on core body temperatures likely 
resulted from self-regulation during exercise.
    Ioannou et al. (2021b) conducted a laboratory based randomized 
control trial in which seven participants completed cycling trials 
under full sun (800 W/m\2\) and full shade (0 W/m\2\) in hot (WBGT 30 
[deg]C) and temperate (WBGT 20 [deg]C) conditions. The full sun 
condition was associated with increased skin temperature at both 
temperatures. Average core body temperature was similar between sunny 
and shaded conditions (37.7 and 37.6 [deg]C for sun versus shade in hot 
conditions and 37.2 [deg]C for both sun and shade in temperate 
conditions). Solar radiation had a small, positive relationship with 
heart rate (average heart rate of 114.0 and 109.1 bpm in sun versus 
shade in hot conditions and 102.6 and 95.4 bpm in sun versus shade in 
temperate conditions) (Ioannou et al., 2021b).
    Although these experimental studies largely assessed the effects of 
shade during exercise and not rest periods, they do support the idea 
that shade reduces heat strain generally; therefore, OSHA preliminary 
concludes that it is reasonable to assume access to shade would also 
reduce heat strain during rest periods. This conclusion is also 
supported by evidence that shade reduces heat exposure (see discussion 
below) and that heat exposure is positively associated with heat strain 
(see discussion in Section IV., Health Effects). OSHA identified no 
major limitations in these studies that would preclude their use in 
drawing conclusions about effectiveness. One aspect of all these 
studies that limit applicability to the larger workforce is that 
participants were all young and healthy and all or mostly male (age was 
not specified in Ioannou et al. (2021b)), and the studies were done for 
relatively short durations of time (2 hours or less). The authors of 
the Otani et al. (2021) and Foster et al. (2022b) studies that used 
artificial solar radiation noted that their studies would not reflect 
changes in the sun's position during the day or changes in radiation 
intensity levels, and that limitation would be relevant to the other 
studies using artificial sources of solar radiation at one intensity 
level.
    There are also two observational studies in the peer-reviewed 
literature that have evaluated the association between shade and risk 
of HRI. In a case-control study of 109 acclimatized construction and 
agriculture workers, Ioannou et al. (2021b) monitored workers for four 
or more consecutive 11-hour shifts, in which environmental factors were 
continuously measured and work hours characterized by the same thermal 
stress but different solar radiation levels were isolated. Solar 
exposure was categorized as either indoors, mixed indoors and outdoors, 
or outdoors, and analyses were done for data collected during 
conditions of 30 [deg]C WBGT. Results included a positive association 
between sun exposure and skin temperature and a significantly higher 
risk for heat strain symptoms (relative risk (RR) = 2.40, 95% CI: 1.78, 
3.24) and reported weakness (RR = 3.17, 95% CI: 1.76, 5.71) among 
workers exposed to solar exposure characterized as outdoors as compared 
to workers exposed to solar exposure characterized as indoors. Core 
body temperature, heart rate, and metabolic rate were not found to be 
associated with sun exposure. The authors attributed the lack of change 
in core temperature and heart rate to the effect of self-pacing. OSHA 
notes that the study did not control for confounding variables.
    Fleischer et al. (2013) used population intervention modeling of 
self-reported HRI symptoms in farmworkers in Georgia to estimate that 
the prevalence of three or more HRI symptoms could have been reduced by 
9.2% (95% CI: -15.2%, -3.1%) if workers could always or usually take 
breaks in the shade. There were limitations to this analysis, including 
the cross-sectional study design, the self-reported exposure and 
outcome data, and low participation rate.
    Additional studies have evaluated differences in microclimatic 
conditions between shady and sunny environments, independent of heat 
strain metrics measured in human subjects. These studies provide clear 
evidence that shade reduces radiant heat (Cheela et al., 2021; do 
Nascimento M[oacute]s et al., 2022; Fournel et al., 2017; Karvatte et 
al., 2016, 2021; Klok et al., 2019; Lee et al., 2020; Middel and 
Krayenhoff, 2019; Sanusi et al., 2016; Zhang et al., 2022). As 
discussed above, indicators of heat strain (e.g., rectal temperature) 
often increase with exposure to solar radiation. These authors examined 
the impact of shade through direct measures that assess radiant heat 
(e.g., globe temperature,

[[Page 70754]]

mean radiant temperature) or through thermal stress metrics (e.g., 
Universal Thermal Climate Index) that incorporate radiant heat in their 
calculation.
    The magnitude of the reduction in radiant heat from shade, however, 
varies by local conditions, with notable factors including the type of 
shade (e.g., trees, buildings, canopies, and other urban structures 
such as solar arrays), percent shade cover, time of day, season, and 
ground cover (due to its role in radiant heat emission). Fournel et al. 
(2017) estimated an average 4.4 [deg]C decrease in black globe 
temperature using data from five studies that assessed different shade 
interventions, while study-specific reductions ranged from 2 [deg]C to 
9 [deg]C. These included a study by Roman-Ponce et al. (1977), who 
observed a 9 [deg]C difference in Florida under an insulated metal 
roof, and a study by Fisher et al. (2008), who observed a 2 [deg]C 
difference in New Zealand under a shade cloth structure. Examples of 
other studies that have evaluated the impact of shade on radiant heat 
include:
     Middel and Krayenhoff (2019) evaluated environmental 
conditions across 22 sites in Tempe, Arizona on the hottest day of the 
summer. They included diverse types of shade, including trees and urban 
structures. The authors concluded that trees decreased afternoon mean 
radiant temperature by up to 33.4 [deg]C and estimated that each 0.1 
decrease in the sky view factor from trees (where a sky view factor of 
1 is a completely open sky and 0 is fully blocked) resulted in an 
approximate decrease of 4 [deg]C in mean radiant temperature (Middel 
and Krayenhoff, 2019).
     Zhang et al. (2022) compared meteorological parameters 
among 12 locations in a coastal city in China. Mean globe temperature 
over the beach in full sun (40.9 [deg]C) was higher than mean globe 
temperatures in areas shaded by dense trees (28.9 [deg]C) or shaded by 
a pavilion canopy (30.8 [deg]C) (Zhang et al., 2022).
     Karvatte et al. (2016) evaluated the impacts of different 
types of natural shade (two densities of eucalyptus trees and isolated 
native trees) on environmental conditions in Brazil. Average black 
globe temperatures from 12 p.m. to 1 p.m. in the shade ranged from 33.2 
[deg]C to 34.3 [deg]C, which were 2.4 [deg]C to 8.2 [deg]C lower than 
that measured in nearby sunny areas (Karvatte et al., 2016).
     do Nascimento M[oacute]s et al. (2022) evaluated the 
effectiveness of four different shade structures (native trees, black 
polypropylene netting, heat-reflective netting, and a combination of 
both types of netting) in the Brazilian savanna. Mean radiant 
temperature was consistently lower under shaded conditions. For 
example, at 11 a.m. and 12 p.m., the peak hours, the mean radiant 
temperatures were 16[deg]C to 20 [deg]C lower in shady conditions than 
sunny conditions (do Nascimento M[oacute]s et al., 2022).
I. Conclusions for Shade
    In conclusion, measurements of environmental conditions indicate 
that exposure to radiant heat is greater in full sun than in shaded 
conditions (e.g., Middel and Krayenhoff, 2019; do Nascimento M[oacute]s 
et al., 2022). It is well known that radiant heat contributes to heat 
stress (NIOSH, 2016). Studies confirm that indicators of heat strain 
(e.g., increased heart rate, increased rectal temperature) are often 
higher in participants exercising in conditions with actual or 
simulated solar radiation versus shade (e.g., Otani et al., 2021). One 
study showed that a 30-minute period of exercising in shade, 
interspersed between two periods of exercising in full sun, resulted in 
improved physiological responses (e.g., lower heat rate, oxygen 
consumption, and sweat loss) compared to the two periods of exercising 
in full sun (Nielsen et al., 1988). OSHA expects that improvements in 
physiological function might have been even greater if the participants 
had rested in shade because resting slows the metabolic generation of 
heat.
    OSHA preliminarily finds that resting in shade will reduce the risk 
of HRI by decreasing exposure to radiant heat that contributes to heat 
stress and can lead to heat strain and then HRI.
C. Fans
    Fans are engineering controls that increase air movement across the 
skin and under the right environmental conditions can increase the 
evaporation of sweat, resulting in greater heat loss from the body. 
However, they may not be appropriate for all environments, such as at 
higher temperatures. Research on the role of fans in HRI prevention 
largely focuses on non-occupational and athletic populations, however 
some chamber trials have been designed to mimic working conditions. A 
summary of the experimental literature is provided here, beginning with 
studies that evaluate the use of fans during physical activity, before 
or after activity, and while people are at rest, and then concluding 
with studies that model efficacy thresholds for fan use.
    Studies by Saunders et al. (2005) and Otani et al. (2018, 2021) 
examined the effects of different air speeds on individuals cycling in 
heated chambers with no rest period included in the study design 
(Saunders et al., 2005: 33.0 [deg]C  0.4 [deg]C and 59% 
 3% RH; air speeds ranging from 0.2 km/hr to 50.1 km/hr; 
Otani et al., 2018: 30 [deg]C and 50% RH; air speeds ranging from 0 km/
hr to 30 km/hr; Otani et al., 2021: 30 [deg]C and 50% RH; air speeds of 
10 and 25 km/hr). In measures of work output, at higher air velocities 
Saunders et al. (2005) reported increased cycling time before 
participants' core temperature reached 40 [deg]C (criteria for 
terminating the trial) and Otani et al. (2018, 2021) reported increased 
time to exhaustion. In lower/no compared to higher air velocities, (1) 
Saunders et al. (2005) reported higher mean body temperature (weighted 
mean of skin and rectal temperature), higher rectal and skin 
temperature, increased heat storage (a measure that considers changes 
in body temperature, in addition to body weight and surface area), and 
lower evaporative capacity; (2) Otani et al. (2018) reported higher 
rectal, skin, and mean body temperature, and lower evaporative heat 
loss; while (3) Otani et al. (2021) reported no significant effect on 
skin temperature but higher rectal temperatures. Higher heart rates 
were also observed at lower/no versus higher air velocities (Saunders 
et al., 2005; Otani et al., 2018, 2021).
    Other studies have examined the effectiveness of fans during both 
exercise and rest periods. In Jay et al. (2019), participants conducted 
arm exercises designed to mimic textile work at 30 [deg]C (86 [deg]F) 
and 70% RH, with and without fanning. In a study by Wright Beatty et 
al. (2015), participants cycled in a chamber at 35 [deg]C (95 [deg]F) 
and 60% RH, with air velocities of 0.5 m/s and 3.0 m/s. Wright Beatty 
et al. designed the study to mimic occupational conditions, like those 
for miners (both workload and clothing). Under the fan/high air 
velocity conditions: (1) Jay et al. (2019) observed a smaller increase 
in rectal temperature, and lower skin temperature, but there was no 
change in heart rate because the study was designed to maintain a 
constant heart rate; and (2) Wright Beatty et al. (2015) observed lower 
rectal temperatures and heart rates. Jay et al. also compared 
effectiveness of fanning to the presence of air-conditioning (7 [deg]C 
lower temperature) and found higher work output and lower rectal 
temperature in both the fanning and air-conditioning groups (relative 
to the hot condition without fanning), while sweat loss was higher with 
fanning compared to air-conditioning (Jay et al., 2019). Wright Beatty 
et al. tested their conditions among both older (~59 years

[[Page 70755]]

old) and younger (~24 years old) participants and observed similar 
benefits of higher air velocity among both age groups (Wright Beatty et 
al., 2015).
    In a handful of other studies, researchers tested the efficacy of 
fan use during rest breaks, after subjects exercised under hot 
conditions (Sefton et al., 2016; Selkirk et al., 2004; Barwood et al., 
2009; Carter, 1999). Conditions for these studies were (1) Sefton et 
al.: 32 [deg]C  0.5 [deg]C and 75%  3% RH, with 
shirt and under shirt removed during cooling, with and without misting 
fan; (2) Selkirk et al.: 35[deg]C and 50% RH wearing firefighting 
protective clothing and breathing apparatuses during exercise and 
removal of protective gear during cooling periods with and without a 
misting fan; (3) Barwood et al.: 31 [deg]C  0.2 [deg]C and 
70%  2% RH, with and without whole body fanning; and (4) 
Carter: 40 [deg]C and 70% RH wearing firefighting protective clothing 
and breathing apparatuses during exercise and removal or unbuckling of 
protective gear during cooling periods with and without a fan. In the 
study by Sefton et al. (2016), rectal temperatures rose during the 
cooling period, regardless of misting fan use, but heart rate was lower 
with misting fan use; the study authors noted that under the high 
humidity conditions of their study, misting fans could have increased 
the moisture in air, thereby reducing cooling through sweat 
evaporation. Other studies found fans or misting fans to be effective 
in improving body temperature or cardiac effects. In comparisons of 
normal recovery conditions (unbuckling of fire-fighting coat and no fan 
use during rest) to enhanced recovery conditions (fire-fighting coat 
was removed and fan used during rest), Carter (1999) reported lower 
rectal and skin temperatures, heart rate, and oxygen consumption during 
enhanced recovery compared to normal recovery conditions. Selkirk et 
al. (2004) reported that the use of a misting fan during rest breaks 
compared to no fan use resulted in lower rates of rectal temperature 
increase, and lower skin temperatures and heart rates. Barwood et al. 
(2009) reported that reductions in rectal and skin temperatures during 
rest periods were greater with fan use than without, but there was no 
significant effect on heart rate. Selkirk et al. (2004) also found that 
participants were able to exercise longer when taking rest breaks with 
misting fans than they were when taking rest breaks without misting 
fans, and Barwood et al. (2009) found that participants were able to 
run farther distances following whole-body fanning.
    Other studies examined the use of fans during breaks in areas 
cooler than where exercise took place. Hostler et al. (2010) conducted 
a study similar to that by Selkirk et al., described above, where 
subjects exercised on a treadmill while wearing firefighting protective 
gear under hot conditions (35.1  2.7 [deg]C, RH not 
specified), but in contrast to Selkirk et al. (2004), rest periods took 
place at room temperature (24.0  1.4 [deg]C) instead of in 
the heat chamber and a non-misting fan was used. In contrast to 
findings from Selkirk et al. (2004), Hostler et al. (2010) reported 
that fanning during breaks had no significant effects on core 
temperature, heart rate, or exercise duration, and they speculated that 
this was because rest breaks took place in a cooler area. The authors 
conclude that active cooling devices may not be needed if the 
temperature of the rest area is below 24 [deg]C (75.2[deg] F). Tokizawa 
et al. (2014) reported that after pre-cooling in an area that was 28 
[deg]C and had 40% RH, participants walking in a heat chamber (37 
[deg]C and 40% RH) wearing protective clothing had lower rectal 
temperatures, heart rate, and weight loss when exposed to fans and 
water spray in the precooling period than the control condition without 
fans and water spray (Tokizawa et al., 2014).
    Additional studies provide information on conditions and 
populations for which fans may or may not be effective. Ravanelli et 
al. (2015; 2017) found that participants (mean age 24  3 
years) were able to be exposed to higher levels of humidity at 
temperatures of 36 [deg]C or 42 [deg]C when using fans before increases 
in esophageal temperatures and heart rate were observed (i.e., 
inflection points) (Ravanelli et al., 2015; Ravanelli et al., 2017). At 
42 [deg]C, the inflection points (when core temperature increases were 
observed) occurred at a relative humidity level of 55% with fans 
compared to 48% without fans. The relative humidity levels where heart 
rate increases were observed with and without fans, respectively, were 
83% and 62% at 36 [deg]C and 47% and 38% at 42 [deg]C. The researchers 
found that heart rate was significantly lower at the end of the trials 
with fans compared to without fans (under 36 [deg]C conditions: 74 
 9 bpm vs. 84  9 bpm; under 42 [deg]C 
conditions: 87  9 vs. 94  9). This was also 
true for esophageal temperatures at the end of the trials (under 36 
[deg]C conditions: 36.7  0.2 [deg]C vs. 36.8  
0.2 [deg]C; under 42 [deg]C conditions: 37.2  0.3 [deg]C 
vs. 37.4  0.2 [deg]C). Rectal temperatures were higher with 
no fans at the end of the trials in both conditions (36 [deg]C and 42 
[deg]C), but these differences were not statistically significant 
(Ravanelli et al., 2017). In contrast, Gagnon et al. (2016) found that 
use of fans did not improve heart rate or core temperature inflection 
points in response to increasing humidity levels, and heart rates and 
core temperatures were higher with use of fans during exposure of older 
adults (mean age 68  4 years) at 42 [deg]C. Gagnon et al. 
speculated that lack of benefits may have resulted from age-related 
impairments to sweat capacity. Morris NB et al. (2019) found that, 
under hot and humid conditions (40 [deg]C, 50% RH; heat index of 56 
[deg]C) fans reduced core temperatures and cardiovascular strain, but 
were detrimental to all outcome measures under very hot but dry 
conditions (47 [deg]C, 10% RH; heat index of 46 [deg]C). The authors 
use these findings to caution against using heat index alone for 
recommendations on beneficial versus harmful fan use.
    While the fan efficacy studies discussed in this section so far 
have been interventional in design, modeling studies have estimated the 
temperature and RH thresholds at which fans are no longer effective at 
reducing heat strain. Jay et al. (2015) argue that public health 
guidelines for when fan use is harmful are too ambiguous and/or too low 
(e.g., ``high 90s'' from the CDC (CDC, 2022). Morris et al. (2021) 
modeled humidity-dependent temperature thresholds at which fans (3.5 
meters/second wind velocity) become detrimental using validated 
calorimetry equations, which calculate net heat transfer between a 
person and their environment. Based on these equations and assumptions 
on reduction in sweat rates among older individuals and individuals 
taking anticholinergic medications, Morris et al. recommend that fans 
should not be used at a humidity-dependent temperature above 39.0 
[deg]C (102.2 [deg]F) for healthy young adults, 38.0 [deg]C (100.4 
[deg]F) for healthy older adults above the age of 65, and 37.0 [deg]C 
(98.6 [deg]F) for older adults taking anticholinergic medication 
(Morris et al., 2021). While the authors provide more exact numbers 
that account for humidity, they provide these thresholds as simple and 
easy guidelines that only require knowing the temperature. Some 
limitations of these studies include the use of assumptions in their 
models that may not be realistic (e.g., fan producing an air velocity 
of 3.5-4.5 meters/second sitting 1 meter away) and the use of 
simplified heat-balance models, which predict the potential for heat 
exchange rather than outcomes such as heat and

[[Page 70756]]

cardiovascular strain metrics (e.g., core temperature, heart rate). 
There are many factors that influence an individual's heat exchange 
potential, such as sex, hydration status, acclimatization status, and 
clothing, and these simplified models often do not account for these 
factors.
    A recent article by Meade and colleagues criticized the simplified 
thresholds published in Morris et al. (2021) as being too high for 
general public health guidance (e.g., recommendations for the general 
public during heat waves) (Meade et al., 2024). The authors modeled 
core temperature changes rather than modeling potential for heat 
exchange, arguing that Morris and colleagues did not consider in their 
conclusions that the potential for greater heat exchange does not 
always translate into increased sweat rates, particularly if core 
temperatures are not high enough to elicit that sweat response. Meade 
and colleagues modeled fan effectiveness under various hypothetical 
environmental conditions and reported the expected impacts on core 
temperatures for a young adult (18-40 years old) at rest wearing light 
clothing. They estimated that fans (versus no fan) would lead to an 
approximately 0.1 [deg]C increase in core temperature at ambient 
temperatures of 37 [deg]C/98.6 [deg]F (when RH is 60-90%), 38 [deg]C/
100.4 [deg]F (when RH is 50-80%), and 39 [deg]C/102.2 [deg]F (when RH 
is 50-80%) (Meade et al., 2024; Figure 1). Fans were estimated to be of 
minimal impact (core temperature change of approximately 0.0 [deg]C) or 
beneficial (reduction in core temperature) compared to no fans in drier 
conditions at these ambient temperatures (37-39 [deg]C). In their 
model, fans were always minimally impactful or beneficial at 
temperatures below 37 [deg]C. Above 39 [deg]C, fans were more often 
harmful (increase in core temperature greater than 0.2 [deg]C). These 
model results were for strong fans (3.5-4.5 m/s air velocity), but in a 
sensitivity analysis, Meade and colleagues present predicted core 
temperature changes for slower fans (1 m/s air velocity) among young 
adults. While these fans are less beneficial than strong fans at low 
temperatures (e.g., below 34 [deg]C/93.2 [deg]F), they were predicted 
to lead to smaller core temperature increases at higher temperatures 
(e.g., 38 [deg]C) and humidities than the stronger fans (Meade et al., 
2024; Figure 4). In another model, the researchers predicted the 
effects of fans combined with skin wetting (relative to no fan or skin 
wetting) among young adults and found this combination was much more 
beneficial than fans alone--they were beneficial or neutral in all 
combinations of humidity and ambient temperature when ambient 
temperature was 40 [deg]C/104 [deg]F or below (Meade et al., 2024; 
Figure 6). One major limitation of these model results is the 
assumption that the individual is at rest, rather than working. Fans 
may be used in work areas, and it would be expected that they would be 
associated with greater heat exchange potential in these scenarios, as 
core temperature would be more likely to remain above levels that 
prompt a sweat response. In a sensitivity analysis, the authors assumed 
a range of metabolic rates, the highest being 90 W/m\2\, which they 
describe as the equivalent to a seated person ``performing moderate 
arts and crafts.'' In this scenario, fans were predicted to be more 
beneficial around 30-34 [deg]C and in drier conditions (RH less than 
30%) up to 39 [deg]C. These numbers may not apply to workers, as 
evidenced in part by findings from a study described above (Carter, 
1999), which found benefits to fans outside the range suggested by 
Meade et al.
    Another study did evaluate fan efficacy among participants 
performing physical work (moderate to heavy workloads), collecting 
empirical evidence from fixed heart rate trials and modeling the 
effects of fans on heat storage at various temperatures and humidities 
(Foster et al., 2022a). Foster et al. conducted 300 trials among 23 
participants (24 cool, 15 [deg]C reference trials, 138 hot trials with 
still air, and 138 hot trials with fans). The hot trials involved a 
range of temperatures and humidities (35-50 [deg]C in 5 [deg]C 
increments and 20-80% RH) and two clothing ensembles--low clothing 
coverage (shorts and shoes) and higher clothing coverage (full-body 
coverall, t-shirt, shorts, and shoes). For the fan trials, they used a 
fan with a speed of 3.5 meters/second. The work output from the cool 
reference trials was used as a baseline to calculate the change in work 
capacity in the hot trials, which was used to validate their 
biophysical model predicting change in heat storage (R-squared = 0.66). 
The authors created categories for the percent change in work capacity 
resulting from fan use relative to no fans--an increase of greater than 
5% was termed ``beneficial'', a decrease of greater than 5% was termed 
``detrimental'', and if the change was an increase or decrease of 5% or 
less, it was called ``ineffective''. In the hot trials, the researchers 
found fans to be beneficial or ineffective at both 35 [deg]C and 40 
[deg]C (depending on the humidity) and ineffective at 45 [deg]C for the 
higher clothing coverage (Figure 1 of Foster et al., 2022a). For the 
low clothing coverage, the researchers found that fans had the 
potential to be beneficial up to 45 [deg]C (at certain humidities), but 
also had the potential to be detrimental at temperatures as low as 35 
[deg]C (specifically when RH was 20%).
    The biophysical model predicting change in heat storage was only 
able to model the effects of fans for the low clothing coverage, 
however, the authors note that the effects of fans were similar across 
clothing groups except that fans weren't beneficial in the high 
clothing coverage at temperatures equal to or above 45 [deg]C. Foster 
et al. used a sweat rate in the model of approximately 1 liter per 
hour, which was the group average from the trials. In Figure 4, the 
authors present the output of their model, which suggests that fans 
become detrimental beginning at a temperature of 39 [deg]C (102.2 
[deg]F) (at certain humidities). At increasing temperatures, fan use is 
detrimental at a wider range of humidity levels (both high and low 
humidity), but beneficial or ineffective at other humidity levels. 
Foster et al. also present model results with varying assumptions for 
sweat rate and fan speed (Figure 6).
    As discussed above, in their consensus statement, Morrissey et al. 
(2021b) recommend the use of electric fans in an occupational setting 
when ambient temperatures are below 40 [deg]C/104 [deg]F.
I. Conclusions for Fans
    In conclusion, OSHA preliminarily finds that these studies show 
that use of fans during work and/or rest breaks will be effective in 
reducing heat strain in the majority of working age adults. Studies 
also show that there are certain conditions (e.g., at a temperature of 
102.2 [deg]F and above, depending on the humidity) under which fans may 
not be beneficial and can be harmful to workers.
D. Water
    Working and sweating in the heat put workers at risk for 
dehydration and HRIs. Replacing fluids lost as sweat is necessary to 
maintain blood volume for cardiovascular function and thermoregulation. 
Multiple studies have examined the efficacy of hydration interventions, 
while also considering various factors that may affect hydration such 
as the quantity of liquid consumed, timing of ingestion, and beverage 
temperature.
    Studies in the peer-reviewed literature provide evidence that 
hydration interventions are effective at combating dehydration and HRI. 
For example, McLellan and Selkirk

[[Page 70757]]

performed a series of heat stress trials with 15 firefighters in Canada 
wearing protective equipment at 35 [deg]C (95 [deg]F) and 50% relative 
humidity (McLellan and Selkirk, 2006). During the trials, participants 
conducted light exercise in a heat chamber and were provided one of 
four fluid replacement quantities: no fluid, one-third fluid 
replacement, two-thirds fluid replacement, or complete fluid 
replacement (based on previously determined sweat rates). Each 
participant completed two 20-minute exercise periods, separated by a 
10-minute break for a simulated self-contained breathing apparatus 
(SCBA) change, and then followed by a 20-minute rest break. Cool water 
was provided during each break. Exercise continued until participants 
reached an endpoint, defined as a rectal temperature over 39.5 [deg]C 
(103.1 [deg]F), heart rate at 95% of maximum, experiencing dizziness or 
nausea, or other safety concerns. Participants who received either two-
thirds or full fluid replacement tolerated approximately 20% more 
exposure time (including rest periods spent in the heat chamber) and 
approximately 25% more work time (calculated by excluding rest periods) 
than those without the fluid replacement. Most participants who were 
not provided fluids ended the trial upon experiencing lightheadedness 
when attempting to re-initiate exercise after a break, possibly related 
to low blood pressure. Those with two-thirds and full fluid replacement 
took significantly longer to reach an end point during work time and 
those with one-third, two-thirds, or full fluid replacement had 
significantly longer exposure time than those without fluid 
replacement. The full fluid replacement group also had higher rectal 
temperatures at their trial endpoint compared to those without fluid 
replacement, possibly indicating that hydration allowed them to 
tolerate higher rectal temperatures. The authors state that these 
findings are consistent with previous literature that reports 
cardiovascular function to be compromised without fluid replacement, 
leading to exhaustion at lower core temperatures.
    Ioannou et al. (2021a) advised intervention groups made up of 
agricultural workers in Qatar and construction workers in Qatar and 
Spain to consume 750 milliliters (mL) of water supplemented by one 
tablespoon of salt per hour over their work shift. Findings in the 
intervention group were compared to a ``business as usual'' (BAU) 
group, where workers followed their normal routine, that were 
unspecified for the agricultural industry and included shaded areas, 
water stations, and air-conditioned rest break areas for construction 
workers in Spain; those same BAU conditions were implemented for 
construction workers in Qatar, in addition to requiring workers to 
carry a water bottle, and education. Results included: (1) 13% to 97% 
reductions in prevalence of dehydration in each intervention group; (2) 
no significant differences in core temperatures for agricultural 
workers in Qatar; (3) significant reductions in core temperature in the 
construction intervention groups in Qatar and Spain, and (4) mixed 
findings on heart rate and skin temperature across the sites. One 
limitation with this paper is the use of BAU as a control group, as it 
is not always clear how these scenarios differed from the intervention. 
In addition, the quantity of fluid consumed was not measured.
    Drinking adequate amounts of water may also reduce the risk of 
syncope. Schroeder et al. assessed the effects of water quantity on 
orthostatic tolerance (as time to presyncope, the symptomatic period 
right before fainting) in healthy individuals (n=13) (Schroeder et al., 
2002). The authors used a controlled, crossover design to test the 
effects of consuming 500 versus 50 milliliters of water prior to 
attempting to induce presyncope by tilting the head-up and applying 
negative pressure to the lower body. They found that drinking the 
larger amount of water improved orthostatic tolerance by 5 minutes (+/- 
1 minute), increased supine (lying down face up) mean blood pressure 
and peripheral resistance, and was associated with smaller increases in 
heart rate. A recent study using a similar design found that the 
temperature of the water may also have an influence--cold water 
consumption was associated with increased systolic blood pressure, 
stroke volume (i.e., increased volume of blood pumped out of heart per 
beat), cerebral blood flow velocity, and total peripheral resistance, 
as well as reduced heart rate relative to consuming room temperature 
water (Parsons et al., 2023). They did not find differences in 
orthostatic tolerance between the groups. It should be noted that 
neither of these papers tested the participants under conditions of 
high heat, but as is discussed in Section IV., Health Effects, research 
has shown that exposure to heat independently increases the risk of 
syncope. In addition, both syncope from exposure to heat and the method 
used to induce presyncope in these studies can involve a mechanism in 
which blood pools in the lower body.
    Public health guidance for workers (e.g., from NIOSH) often 
involves recommendations that workers consume 1 cup (237 mL) of water 
every 15-20 minutes or approximately 1 liter (711-948 mL) per hour. The 
goal is to replenish fluids lost through sweat and avoid a substantial 
loss in total body water content. Sweat rates vary between individuals 
and conditions. Research conducted among workers performing ``moderate 
manual labor e.g., mining or construction work'' in a controlled 
laboratory setting (35 [deg]C and 50% RH) demonstrated an average sweat 
rate of 410-470 mL per hour (depending on whether the trial was 
conducted in winter or summer), but a range of 100 mL to 1 liter per 
hour during the presumed unacclimatized trials (conducted in winter) 
(Bates and Miller, 2008). These recommendations are also in line with 
the Army's fluid replacement guidelines, which recommend 0.75-1 quart 
(1 quart is approximately 0.95 liters) per hour for ``moderate work'' 
(425 W) to ``heavy work'' (600 W) depending on the wet bulb globe 
temperature (Department of the Army, April 12, 2022; Table 3-2).
    In a randomized crossover study, Pryor et al. (2023) had 
participants continuously walk for two hours at 6.4 km/hr in a heat 
chamber (34 [deg]C/93.2 [deg]F, 30% relative humidity) while either 
drinking 500 mL of water every 40 minutes or 237 mL of water every 20 
minutes, followed by two hours of rest. Study authors found both 
hydration strategies to be similarly effective based on (1) no 
significant differences in body mass, percent change in plasma volume, 
plasma osmolality (i.e., volume of particles dissolved in plasma), body 
temperature, or heart rate and (2) no difference in thirst or total 
gastrointestinal symptom scores. The authors did note, however, that 
urine volume was significantly lower after the rest period in the group 
receiving 237 mL of water every 20 minutes compared to the group 
receiving 500 mL of water every 40 minutes.
    Several studies have evaluated the impact of the temperature of 
drinking water on dehydration and other measures in occupational 
settings. Cold water may serve as a heat sink to cool off the body in 
addition to combatting dehydration. In their meta-analysis, Morris et 
al. (2020) (described above) considered the effect of cold fluid 
ingestion as a personal cooling method, distinct from maintaining 
hydration status. Morris and co-authors concluded that cold fluid 
ingestion was effective as a heat strain mitigation control.
    A systematic review by Burdon et al. reported that palatability was 
higher for

[[Page 70758]]

cold (32.0-50.0 [deg]F) or cool (50.0-71.6 [deg]F) beverages, as 
compared to warmer (greater than 71.6 [deg]F) beverages, during 
exercise (Burdon et al., 2012). The authors conducted a meta-analysis 
using data from five studies and found that participants drank roughly 
50% more cold/cool beverages than warmer beverages. Another analysis of 
multiple studies found that when participants were provided cold/cool 
beverages rather than warmer ones, there was less of a mismatch between 
fluid intake and fluid lost through sweat (measured as percentage of 
body mass lost). Participants provided warmer beverages lost, on 
average, 1.3% more of their body mass (95% CI: 0.9%, 1.6%) (Burdon et 
al., 2012).
I. Conclusions for Water
    In conclusion, one experimental study reported that drinking 
adequate amounts of water while exercising in high heat prolonged the 
time of exposure before experiencing signs of heat strain or HRI 
(McLellan and Selkirk, 2006). In addition, studies in which 
participants were not exposed to high temperatures found that drinking 
adequate amounts of water reduced the risk of laboratory-induced 
presyncope (Schroeder et al., 2002), and drinking cool water improved 
cardiovascular function (Parsons et al., 2023). Studies have also 
reported increased palatability for cool or cold beverages (<=71.6 
[deg]F) that is likely to increase consumption and prevent dehydration 
compared to warmer beverages (Burdon et al., 2012).
    Based on these studies, OSHA preliminarily finds that drinking 
adequate amounts of water is an effective intervention for preventing 
heat strain that could lead to HRI, and that providing cool drinking 
water is especially beneficial. In addition, because cool or cold water 
was found to be more palatable than warm water, OSHA preliminarily 
finds that providing cool or cold water can lead to higher consumption 
of water and thereby reduce the risk of dehydration.
E. Acclimatization
    Heat acclimatization refers to the improvement in heat tolerance 
that occurs from gradually increasing the intensity and/or duration of 
work done in a hot setting. There are several studies examining the 
extent and effectiveness of acclimatization achieved on the job. The 
effects of acclimatization in allowing individuals to work safely in 
higher temperatures than unacclimatized individuals has been 
established for decades and is reflected by both the NIOSH REL and the 
ACGIH TLV (NIOSH, 2016; ACGIH, 2023).
    Early research on the effectiveness of acclimatization was 
conducted in the 1950s and 1960s among gold mine workers in South 
Africa (Weiner, 1950; Wyndham et al., 1954, 1966). Weiner (1950) 
conducted three days of heat stress tests on eight acclimatized mine 
workers, with three to six months experience working underground, and 
eight new, unacclimatized workers. Workers completed a four-hour 
protocol of step climbing sessions (30 mins) with sitting breaks (30 
mins) in a mine shaft (dry bulb temperatures: 89.8 [deg]F-90.2 [deg]F, 
wet bulb temperatures: 88.8 [deg]F-89.1 [deg]F, air movement: 165-280 
ft/min). Multiple unacclimatized workers were not able to complete the 
full protocol on the first day (based on symptomology, heart rate and 
rectal temperature), while all acclimatized workers were able to do so. 
Rectal temperatures and heart rates were higher among the 
unacclimatized workers than the acclimatized workers and sweat rate was 
lower (Weiner 1950).
    Wyndham et al. (1954) describe a two-stage acclimatization protocol 
in which workers (n=110) shoveled rock for six days in a cooler section 
of the mine (saturated air temperature approximately 86.5 [deg]F, wind 
velocity approximately 100 feet/minute), before moving to a hot section 
of the mine (saturated air temperature between 91.5 [deg]F and 92.0 
[deg]F, wind velocity 100 to 350 feet/minute) to complete the same task 
for six more days (Wyndham et al., 1954). Researchers measured rectal 
temperatures before the shift, at 9 a.m., at 11 a.m., and at 1 p.m. on 
each of the twelve days. Average rectal temperature was 101.0 [deg]F on 
the first day in the cooler conditions, which fell to 100.2 [deg]F on 
day six. When workers transitioned to the hot conditions, the average 
rectal temperature was 100.8 [deg]F on the first day and 100.0 [deg]F 
on the sixth day. The authors concluded that the acclimatization method 
was a success, as rectal temperatures were on average lower on the 
first day in full heat conditions (100.8 [deg]F) than on the first day 
of work in cooler conditions (101.0 [deg]F), and mean work output was 
also higher on the first day in the full heat (Wyndham et al., 1954). 
The researchers also compared the acclimatized workers to a prior 
cohort of eight new workers who worked immediately in hot conditions 
without any acclimatization--they had an average rectal temperature of 
101.8 [deg]F on their first day. The authors noted that the two-stage 
acclimatization protocol likely resulted in complete acclimatization, 
as earlier monitoring of the eight new workers over 23 workdays showed 
that rectal temperatures did not fall much lower than 100 [deg]F, the 
average temperature seen after the new two-phase acclimatization 
protocol (Wyndham et al., 1954).
    In a later study, Wyndham et al. (1966) analyzed the rectal 
temperatures of 18 acclimatized men and groups of 20 unacclimatized men 
working at a moderate rate for four hours in varying environmental 
conditions (Wyndham et al., 1966). The authors found that the 
acclimatized men, on average, could work at higher effective 
temperatures (a heat metric that accounts for ambient temperature, 
humidity, and air movement) than the unacclimatized men while still 
maintaining a steady rectal temperature (Wyndham et al., 1966).
    Van der Walt and Strydom analyzed fatal heat stroke cases among 
miners in South Africa from 1930-1974 (Van der Walt and Strydom, 1975). 
Changes in cooling, mechanization, and acclimatization practices 
occurred at different points in time. Van der Walt and Strydom divided 
1930-1974 into four periods based on interventions implemented during 
each period. They discussed changes in heat stroke fatality in relation 
to the interventions that were implemented. During the earliest period 
(1930-1939), acclimatization practices were introduced and ventilation 
improved, and the annual heat stroke mortality rate decreased from 93 
to 44 deaths/100,000 workers. During the following period, which 
coincided with the war and post-war time (1940-1949), mines continued 
and improved the practices introduced in the first period. There was a 
drop in mortality rate from approximately 26 to 16 deaths/100,000 
workers. During the third period (1950-1965), mines began using two-
stage acclimatization, and the annual heat stroke mortality rate 
decreased from 15 to 5.6 deaths/100,000 workers. During the fourth 
period (1966-1974), mines began using climatic room acclimatization, 
and the annual heat stroke mortality rate decreased even further to 2.3 
deaths/100,000 workers (Van der Walt and Strydom, 1975). The authors 
concluded that the controls they implemented over this period--namely 
introducing and improving their acclimatization procedures--were 
important in reducing the heat stroke fatality rates over time. 
However, they also introduced other controls during this time 
(ventilation and mechanization) so it is difficult to determine the 
efficacy of acclimatization independent of those controls (and other 
potential confounding factors).

[[Page 70759]]

    Recent research on acclimatization has also included studies that 
assess acclimatization achieved while on the job. Lui et al. (2014) 
conducted a study to evaluate acclimatization among firefighters before 
and after a four-month wildland fire season, in May and September, 
respectively. The researchers assessed various physiological markers of 
heat acclimatization among a cohort of 12 U.S. male wildland 
firefighters and a group of 14 adults who were not firefighters, 
matched on age and fitness level. Participants completed a 60-minute 
walk at 50% of peak oxygen consumption (VO2) in a chamber at 43.3 
[deg]C and 33% relative humidity. At 60 minutes, firefighters were 
found to have lower average core body temperatures after the wildfire 
season than before the season (after: 38.2 [deg]C  0.4; 
before: 38.5 [deg]C  0.3), while the comparison group 
showed no difference from the pre-season to post-season trials. 
Similarly, firefighters had significantly lower physiological strain 
index scores (a variable derived from core temperature and heart rate) 
after the wildfire season (p<0.05), while scores did not change for the 
comparison group. No pre- to post-season changes were observed for 
heart rate. The authors found no evidence of acclimatization in the 
comparison group over the study period. Study results suggest that the 
firefighters were acclimatized due to occupational exposures during the 
wildfire season rather than exposure to higher seasonal heat (Lui et 
al., 2014).
    Dang and Dowell (2014) compared heat strain markers among 
acclimatized and unacclimatized potroom workers at an aluminum smelter 
in Texas in July as they conducted various smelting activities in high 
heat. Workers were defined as unacclimatized if they had not been 
working or had been working solely outside of the potrooms for four or 
more consecutive days in the prior two weeks. WBGT values in work areas 
ranged from 83 [deg]F to 120 [deg]F. Among the eight unacclimatized 
workers and 48-50 acclimatized workers with heat strain measurements, 
unacclimatized workers had significantly higher average heart rates 
than acclimatized workers (118 bpm vs. 107 bpm, p<0.01). Unacclimatized 
workers also had higher average and average maximum core temperatures, 
but these differences were not significantly different (average maximum 
core temperature: 101.0 [deg]F vs. 100.7 [deg]F; average core 
temperature: 99.7 [deg]F vs. 99.6 [deg]F) (Dang and Dowell, 2014).
    Watkins et al. (2019) evaluated the heat tolerance of fire service 
instructors (FSIs), which researchers describe as fire personnel who 
provide firefighting training courses and have more frequent fire 
exposure than firefighters. The researchers conducted two heat 
tolerance tests, separated by two months on a cohort of 11 FSIs and 11 
unexposed controls (university lecturers), matched on age, sex, and 
body composition. Controls had not had more than three consecutive days 
of heat exposure (<25 [deg]C) or taken part in heat acclimatization 
training in the month prior to the study. On average, FSIs experienced 
five fire exposures in the two weeks prior to each heat tolerance test. 
Each test was composed of a 10-minute rest period (22.9  
1.2 [deg]C, 31.2  6.8% RH) followed by a 40-minute walk in 
a heat chamber (50  1.0 [deg]C, 12.3  3.3% RH) 
wearing fire protective equipment. At the end of the first heat 
tolerance test, FSIs on average had significantly lower maximum rectal 
temperature (-0.42 [deg]C, p<0.05), less change in rectal temperature 
(-0.33 [deg]C, p<0.05), and reported less thermal sensation and, among 
males only, a higher sweat rate (+0.25 Liters/hour, p<0.05) than the 
controls. Heart rate, skin temperature, and physiological strain index 
did not differ between groups. Rectal temperature at the end of the 
heat test was negatively correlated with the number of fire exposures 
experienced in the prior two weeks (r= -0.589, p=0.004) (Watkins et 
al., 2019).
    The effectiveness of acclimatization in high heat conditions has 
also been an important topic for militaries. Charlot et al. (2017) 
studied the effects of training on acclimatization in 60 French 
soldiers who arrived in United Arab Emirates (UAE) in May of 2016, and 
were not stationed in a hot climate over the previous year. On day 1, 
all soldiers completed a heat stress test while running. On days 2-6, 
the 30 soldiers in the training group trained outdoors by running at 
50% VO2 max, with durations of training sessions ranging from 32-56 
minutes. Both the soldiers in the training group and 30 soldiers in a 
control group (no training; performed usual activities) spent 
approximately six hours outdoors per day conducting standard military 
tasks. The heat stress test was repeated on day 7, with WBGTs ranging 
from 1.1 [deg]C warmer to 0.9 [deg]C cooler compared to day 1. In both 
groups, rectal temperature, heart rate, sweat loss, sweat osmolality, 
perceived exertion, and thermal discomfort were lower after the stress 
test on day 7 compared to day 1. Compared to the control group, the 
training group had significantly greater decreases in heart rate (20 
 13 bpm lower versus 13  6 bpm lower), rate of 
perceived exertion, and thermal discomfort after the stress test on day 
7 compared to day 1. Charlot et al. (2017) concluded that addition of 
short, moderate-intensity training sessions resulted in further heat 
acclimatization, beyond the acclimatization observed across all 
participants.
    In another study of military trainees, Lim et al. (1997) assessed 
the degree to which passive heat exposure and military training 
resulted in the acclimatization of army recruits in Singapore across a 
16-week military training program. Participants completed a heat stress 
test, while marching, at four time points: (1) before starting the 
program, (2) on the second week, (3) on the sixth week and (4) on the 
sixteenth/final week of the program. For the nine individuals who 
attended all tests, heart rate significantly decreased across the study 
period, while results for skin temperature, tympanic temperature (i.e., 
within ear canal), and average body temperature were mixed, and there 
were no significant differences in sweat loss or sweat rate. 
Researchers interpreted these findings to mean that passive heat 
acclimatization from living in a hot climate had resulted in partial 
acclimatization, but that physical conditioning was necessary for 
triggering beneficial cardiovascular adaptations (Lim et al., 1997).
    Sports teams have also evaluated the effectiveness of heat 
acclimatization among their athletes. Three studies conducted among 
professional soccer players found that athletes training in hot outdoor 
conditions experienced improvements in plasma volume, heart rate, 
rectal and skin temperature, and/or sweat sodium concentration over the 
course of their training (Buchheit et al., 2011; Racinais et al., 2012, 
2014).
    Acclimation (i.e., improvement in heat tolerance under laboratory 
conditions) was also studied in heat chamber studies. In a study using 
90-minute treadmill sessions designed to mimic the metabolic rate of 
manual laborers, Chong et al. (2020) found that over the course of a12-
day acclimatization period at 28 [deg]C WBGT or 30 [deg]C WBGT, peak 
core temperature, heart rate, and skin temperature decreased and sweat 
rate increased even before the end of the 12-day period (Chong et al., 
2020). Zhang and Zhu (2021) acclimated participants using 10 daily 90-
minute treadmill sessions (at a speed of 5 kilometers/hour) in 38 
[deg]C and 40% RH and found that after acclimation, rectal temperature 
and heart rate during exercise increased at a slower rate, but there 
was no effect on

[[Page 70760]]

skin temperature. OSHA notes that Zhang and Zhu (2021) did not 
gradually increase daily heat exposure, as is typically recommended.
    Shvartz et al. (1977) studied the effects of work and heat on 
orthostatic tolerance among 12 trained men (i.e., trained three time a 
week in endurance sports) and 16 untrained men, none of whom were 
exposed to exercising in the heat in the two months before testing 
(Shvartz et al., 1977). The trained participants had better orthostatic 
tolerance to laboratory-induced syncope compared to the untrained 
participants (2 vs. 8 fainting episodes after exercise in ambient 
conditions; 4 versus 9 fainting episodes after exercise in heat). Heat 
acclimation improved orthostatic response, as fainting episodes after 
exercise decreased in the 8 untrained participants who were later 
acclimated to heat for 7 additional days (4 versus 0 fainting episodes 
after exercising in temperate conditions and 4 versus 2 after 
exercising in hot conditions, before and after acclimation, 
respectively). At the end of the acclimation period for those 8 
untrained participants, significant reductions were observed for heart 
rate and rectal temperature, while significant increases in sweat rate 
and maximum VO2 occurred. Shvartz et al. (1977) concluded that both 
general physical fitness and heat acclimation contributed to better 
orthostatic responses and fewer fainting episodes.
    Parsons et al. (2023) evaluated the effects of heat acclimation in 
20 endurance-trained athletes (15 males, 5 females) randomly assigned 
to a heat group that was acclimated for 8 days or control group that 
was not acclimated to heat. Heat stress testing (at approximately 32 
[deg]C and 71% or 72% RH) revealed that in the post-intervention 
period, the heat group compared to the control group, had significantly 
decreased peak heart rate; resting, mean, and peak rectal temperature; 
and peak and mean skin temperature. No significant differences were 
observed in measures of sweat and hydration. Plasma volume was 
significantly increased in the heat compared to control group post 
intervention. Orthostatic tolerance (at approximately 32.0 [deg]C, 20% 
RH) determined by the time to laboratory-induced presyncope, was 
significantly increased in the heat group (pre: 28  9 min. 
vs. post: 40  7 min.) compared to control group (pre: 30 
 8 min. vs. post: 33  5 min.) post-
intervention. The authors concluded that plasma volume expansion was 
the likely mechanism behind improved orthostatic tolerance; they 
further noted that participants were physically fit at baseline and 
that they would expect a less robust acclimation regimen would likely 
yield beneficial results for populations with lower physical fitness 
(Parsons et al., 2023).
I. Evidence of Tenure as a Risk Factor
    Multiple investigations of occupational HRIs have identified tenure 
in the job as a risk factor. Workers who are new on the job are often 
overrepresented in HRI and heat-related fatality reports. In many of 
these cases, this apparent increased risk presumably results from not 
being acclimatized to hot working conditions. Studies documenting 
tenure as a risk factor include case series from OSHA reports, analyses 
of State workers' compensation databases, and research on military 
populations. For reference, the most recent (2023) monthly estimates of 
new hires in the U.S. suggest that over the summer months (June to 
September), the percent of workers who have been in their job for a 
month or less ranges from 3.7%-4.1% (BLS JOLTS 2023). Therefore, the 
percent of workers who are in their first day, first week, or first two 
weeks on the job would be expected to be lower than 3.7%-4.1%.
    Several reports have evaluated OSHA enforcement cases of HRI and 
heat-related fatalities. Arbury et al. identified 20 citations 
involving indoor or outdoor HRIs and fatalities cited under the general 
duty clause in 2012 and 2013 (Arbury et al., 2014). Of the 13 
fatalities, 4 (31%) occurred on the worker's first day on the job or 
after returning from time away, while 9 (69%) occurred in the first 
three days of the worker's tenure on the job. Arbury et al. expanded 
this work in a follow-on report that included all of OSHA's heat 
enforcement cases in both indoor and outdoor workplaces between 2012 
and 2013 (n=84). Of the 23 cases involving a heat-related fatality, 17 
(74%) occurred in the worker's first three days on the job and 8 (35%) 
on the worker's first day (Arbury et al., 2016). Tustin et al. (2018a) 
identified 66 HRI cases among OSHA enforcement investigations conducted 
between 2011 and 2016 for which OSHA's Office of Occupational Medicine 
and Nursing (OOMN) was consulted. Among the fatality cases with job 
tenure information (n=22), 45.5% occurred on the first day of or 
returning to the job and 72.8% occurred during the first week. Among 
the non-fatal HRI cases with job tenure information (n=32), 3.1% 
occurred on the first day and 18.7% occurred during the first week. In 
a related analysis focusing on outdoor workers, Tustin et al. (2018b) 
evaluated 25 outdoor occupational HRI and fatalities investigated by 
OSHA between 2011 and 2016. Eleven (78.6%) of the 14 fatalities and one 
of the 11 non-fatal illnesses (9.1%) occurred in workers who had 
started the job within the preceding two weeks or returned from an 
absence of greater than one week (Tustin et al., 2018b).
    Arbury et al. 2014, Arbury et al. 2016, Tustin et al. 2018a, and 
Tustin et al. 2018b are all retrospective case series that used OSHA 
databases to identify cases of HRI and heat-related fatalities. As 
such, they rely on previously collected information about working 
conditions and worker characteristics, which may not be complete or 
reflect all factors. In addition, there may be selection bias 
introduced by the type of cases referred to OSHA's OOMN for review 
(i.e., they may represent more severe cases).
    Several studies and reports have used data from California to 
describe characteristics of occupational HRI and heat-related 
fatalities in the State. From May through November of 2005, there were 
25 heat-related Cal/OSHA enforcement investigations (Prudhomme and 
Neidhardt, 2006). When combining fatal and non-fatal outcomes, most 
workers (80%) had been on the job for four or fewer days before their 
HRI event, and almost half (46%) occurred on the workers' first day on 
the job (Prudhomme and Neidhardt, 2006). In 2006, Cal/OSHA confirmed 46 
cases of HRI in their 38 investigations of heat-related allegations (4 
investigations involved more than 1 case) (Prudhomme and Neidhardt, 
2007). 15% of the HRI events and fatalities occurred on the first day 
of work or the first day of a heat wave, while 30% occurred after 
working one to four days on the job or into a heat wave (Prudhomme and 
Neidhardt, 2007). It should be noted that both Cal/OSHA reports only 
capture cases investigated by Cal/OSHA, and as such, may reflect more 
severe cases of HRI. They are also not expected to be exhaustive of all 
occupational HRIs occurring in the State during these time periods. 
Heinzerling et al. (2020) investigated occupational HRIs across 
industry sectors in California from 2000 to 2017 using the California 
Workers' Compensation Information System (Heinzerling et al., 2020) and 
identified 15,996 cases of occupational HRI. The authors reported that 
1,427 cases (8.9%) occurred within two weeks of hire and 410 (2.6%) 
occurred on the first day on the job.
    Several analyses of Washington State Department of Labor and 
Industries (WA L&I) data have also investigated job tenure in relation 
to heat-related workers' compensation claims. Bonauto

[[Page 70761]]

et al. identified 308 claims between 1995 and 2005 with information on 
employment duration, 43 (14%) of which reported job tenure of one week 
or less (Bonauto et al., 2007). In comparison, across all claims (i.e., 
not just heat-related) with employment duration information during the 
same period, 3.3% of claims reported a job tenure of one week or less, 
suggesting that this pattern is more common among heat-related claims. 
A more recent analysis by WA L&I reports the percent of accepted HRI 
claims occurring during the first one and two weeks of work in 
Washington between 2006 and 2021 (SHARP 2022). Across all industries, 
12.5% of accepted HRI claims were filed in the first week at a job and 
16.1% of accepted HRI claims occurred during the first two weeks of 
work. The percentage of HRI claims filed in the first week and first 
two weeks of working at a job was higher than the percentage among all 
workers' compensation claims filed in the first week (2.2%) or two 
weeks (3.7%) on a job. Spector et al. conducted an analysis similar to 
Bonauto et al. 2007, but restricted to the agriculture and forestry 
sectors and included claims through 2009 (Spector et al., 2014). The 
researchers identified 84 HRI claims in the agriculture and forestry 
sectors, approximately 15% of which reported that claimants had been 
working at their job for less than two weeks at the time of the injury. 
As discussed in Section V.A., Risk Assessment, occupational HRIs, 
particularly those not requiring medical treatment, are subject to 
underreporting in workers' compensation systems. Therefore, injuries 
and illnesses that are captured are likely to be more severe cases.
    The U.S. military has also studied HRIs among its recruits 
extensively. Among all U.S. Marine recruits entering basic training at 
the Marine Corps Recruit Depot, Parris Island in South Carolina between 
1988 and 1996, the number of HRI cases were higher in early training 
periods (processing week and weeks 1-4) compared to late training 
period (training weeks 5-12) for females but were similar for males 
(Wallace 2003). Among males, weeks 1, 8, and 9 of training had the 
highest numbers of HRI cases. Physical intensity of training varied 
each week during the 12 weeks of training, which likely had an impact 
on rates of HRI. Dellinger et al. reported on HRIs among more than 
7,000 Army National Guard soldiers deployed to Illinois from July 5th 
to August 18th, 1993, in response to severe flooding (Dellinger et al., 
1996). Researchers identified 23 heat-related medical claims, which 
excluded those treated by on-site first aid. 65% of the 23 HRI claims 
occurred during the first two weeks of the deployment; researchers note 
that this was also the period of greatest work intensity.
II. Conclusions for Acclimatization
    In conclusion, numerous studies have reported the benefits of heat 
acclimatization for employees in workplace settings. For example, 
adoption of workplace acclimatization protocols was followed by reduced 
rates of heat stroke-related fatalities in South African miners (Van 
der Walt and Strydom, 1975). Acclimatization was also reported to 
result in reduced signs of heat strain or improved physiological 
responses to heat for miners (Weiner, 1950; Wyndham et al., 1966), fire 
fighters (Lui et al., 2014; Watkins et al., 2019) and aluminum smelter 
potroom workers (Dang and Dowell, 2014). Similarly, studies in military 
personnel have reported responses to heat following physical training 
in hot climates (Charlot et al., 2017; Lim et al., 1997). Improvements 
in physiological responses to heat were also observed in athletes after 
training in hot climates (Buchheit et al., 2011; Racinais et al., 2012, 
2014) and participants exercising in heat chambers (Chong et al., 2020; 
Zhang and Zhu, 2021). Studies have also shown that heat acclimation 
while exercising reduces the risk of laboratory-induced syncope 
(Shvartz et al., 1977) or presyncope (Parsons et al., 2023).
    Additionally, retrospective examination of limited data from State 
and Federal enforcement and surveillance cases demonstrates over-
representation of workers during the first days or weeks of employment 
or return to work among HRI cases and fatalities (Arbury et al., 2014, 
2016; Tustin et al., 2018a, b; Prudhomme and Neidhardt, 2006, 2007; 
Heinzerling et al., 2020; Bonauto et al., 2007; SHARP, 2022). This 
suggests that these workers are at increased risk of HRI and fatality, 
which may be (or at least in part) the result of lack of 
acclimatization.
    Based on the evidence presented in this section, OSHA preliminarily 
finds acclimatization to be an effective intervention in reducing the 
risk of HRI and heat-related fatality by improving physiological 
responses to heat.
IV. Evidence on the Effectiveness of Multicomponent Interventions
A. Civilian Workers
    OSHA identified a small number of studies that examined the 
effectiveness of multi-pronged interventions implemented at workplaces. 
Three evaluated the effectiveness of a multi-pronged intervention at 
reducing the risk of heat-related illness (McCarthy et al., 2019; 
Perkison et al., 2024) or self-reported symptoms of heat-related 
illness (Bodin et al., 2016) by comparing the same study population 
before and after an intervention was implemented. OSHA does note that 
the studies lacked a control group which received no intervention and 
would have allowed for the authors to examine the effect of potential 
temporal confounders that changed across the study period. In addition, 
there was no data to indicate how thoroughly the interventions were 
implemented or how much employees adhered to them. However, the studies 
provide strong and consistent evidence of the effectiveness of multi-
intervention programs in preventing heat-related illnesses and are 
supported on a mechanistic basis by the laboratory and other 
experimental evidence presented above.
    McCarthy et al. (2019) compared HRI events and costs from workers' 
compensation data before and after a Heat Stress Awareness Program 
(HSAP) intervention among workers in a mid-sized city in Central Texas 
that was implemented in March 2011. The study population consisted of 
municipal workers whose jobs involved work in hot, humid conditions 
with moderate to heavy physical demands, excluding firefighters. The 
HSAP was based on NIOSH's Criteria for a Recommended Standard: 
Occupational Exposure to Heat and Hot Environments (2016) and included 
in-person training of supervisors and workers, a medical monitoring 
program, and specific recommendations to supervisors such as providing 
unlimited access to water, sports drinks, and shade, as well as 
establishing acclimatization schedules, work-rest procedures, and first 
aid protocols. Before the intervention, workers completed a self-
administered questionnaire to determine their level of HRI risk, which 
the researchers then used to categorize them into four risk levels 
(McCarthy et al., 2019). Those who reported two or more HRI risk 
factors (i.e., high body mass index, medication use, chronic illnesses, 
alcohol and energy drink use, history of prior HRI, work in a second 
hot job, and extensive skin pathology) but not an ``unstable health 
condition'' received individualized HRI prevention counseling or 
education.
    McCarthy et al. (2019) compared the rates of heat-related illness 
across the study period of 2009-2017, before and after the HSAP 
intervention was implemented in 2011. In the pre-intervention period 
(2009-2010), the

[[Page 70762]]

annual average claim rate for heat-related illnesses was 25.5 claims/
1,000 workers. The average annual rate of HRI claims in fell by 37% in 
2012-2014 (16 claims/1,000 workers) and by 96% in 2015-2017 (1 claim/
1,000 workers) compared to the pre-intervention period. No workers' 
compensation claims for HRI were submitted in the final 2 years of the 
study period.
    OSHA observes the potential for healthy worker selection bias in 
this study that might have occurred if employees with medical 
conditions were more likely to leave their job and therefore the cohort 
during the study period.
    Perkison et al. (2024) reported that the program in the central 
Texas Municipality employees (referred to in this study as the heat 
illness prevention program (HIPP)) and described by McCarthy et al. 
2019) ended in 2017 and was replaced by a modified HIPP (mHIPP) that 
included only employee and supervisor training and employee 
acclimatization. In an analysis to determine the impact of dropping 
medical surveillance from the HIPP, the study authors reported that the 
rate of heat illness and injury, which averaged 19.5/1,000 employees 
during the first four years of the HIPP (2011-2014), fell to 1.0/1,000 
employees over the next three years (2015-2017), but increased to 7.6 
per 1,000 workers during the mHIPP (2018-2019). Although heat-related 
illness claim rates increased during implementation of the mHIPP, the 
rate of heat-related illness during implementation of the mHIPP (7.6/
1,000) was still 70% lower than the period with no intervention (25.5/
1,000).
    Bodin et al. (2016) reported on productivity, HRI symptoms, and 
hydration practices before and after a water-rest-shade (WRS) and 
efficiency intervention among sugarcane cutters in El Salvador. The 
intervention began two months into the 5-month harvest season of 2014-
2015. The WRS intervention included: 3-liter water bladders carried in 
backpacks and refilled during breaks; an initial 1.5 to 2-hour work 
interval followed by a 10 to 15-minute break, then hour-long work 
periods with 10 to 15-minute rest breaks and a 45-minute lunch break; 
and a portable shade canopy for breaks. The efficiency intervention 
consisted of a machete with an improved blade and handle, fewer rows 
cut, and a stacking method to reduce workload. Due to challenges during 
data collection, a relatively small sample size of 41 workers completed 
follow-up. Bodin et al. (2016) reported that, among those 41 sugarcane 
cutters, average daily water intake (5.1 liters pre-intervention, 6.3 
liters post-intervention) and average daily production (5.1 tons pre, 
7.3 tons post) increased after the intervention. An analysis of self-
reported heat stress and dehydration-associated symptoms showed that 
reporting of most symptoms decreased after the intervention, such as 
feeling feverish (40% to 10%), exhaustion (37% to 14%), nausea (35% to 
12%), very dry mouth (49% to 26%), very little urine (37% to 19%), 
cramps (30% to 17%), diarrhea (14% to 0%), disorientation (12% to 0%), 
and fainting (5% to 2%). However, self-reported rates of vomiting (9% 
to 10%) and dysuria (i.e., pain during urination) (42% to 45%) remained 
similar in pre- and post-intervention periods (Bodin et al., 2016) 
(Communication with David Wegman, November 2023).
B. Military Personnel
    OSHA also identified studies which examined the effectiveness of 
interventions in reducing risk of heat-related illness among military 
personnel. OSHA acknowledges differences between military personnel and 
typical civilian worker populations, such as health status, fitness 
levels, and the types of physical activities performed by military 
personnel (e.g., long-distance running). The military also employs 
certain controls that aren't typically used in workplaces, such as work 
stoppage criteria. However, OSHA finds the studies in military 
personnel useful for showing that multi-component interventions can 
reduce the risk of heat-related illness.
    Kerstein et al. (1986) conducted a randomized control trial in 
military reservists exposed to hot and humid conditions and found that 
the incidence of heat illness was 54% lower in a group exposed to 
intervention measures. Those measures included a lecture on water as 
prevention, training on and use of portable WBGT monitors, and a 
special briefing for Commanding Officers. Incidence rates of HRI 
(defined as ``any person with heat symptoms, including exhaustion, 
cramps, and headaches that the corpsman could clearly relate to the 
environment and cause the individual to be non-functional for at least 
one hour or more'') were 13 out of 306 participants in the intervention 
group (4.2%) and 20 out of 220 in the control group (9.1%).
    Stonehill and Keil examined the number of heat stroke cases at 
Lackland Air Force Base in San Antonio, Texas after they implemented a 
series of interventions over a period from 1956 through 1959 (Stonehill 
and Keil, 1961). Interventions that were implemented before 1958 
included education on heat illness and prevention, pausing training 
based on dry bulb temperatures, shifting harder exercises to cooler 
hours, treating heat rash, providing clothing with better ventilation, 
improving personal hygiene, providing special advice for overweight 
individuals, and implementing immediate medical treatment for heat 
stroke. Despite these measures, they still observed 39 cases of heat 
stroke in 1957 (a rate of 0.87/1,000). After making improvements to 
their prevention measures in the summer of 1958 (increased water and 
salt tablet availability, removing fatigue shirts inside classrooms, 
using WBGT to determine when to pause training, and avoiding intense 
outdoor training in the first week of training), they observed only 2 
heat stroke cases that summer (a rate of 0.05/1,000), a reduction of 
95% from 1957.
    Minard (1961) evaluated the effectiveness of interventions in 
reducing HRIs in a study of the Marine Corps Recruit Depot in Parris 
Island, South Carolina. During the summer of 1952, the mean weakly HRI 
incidence rate was 53 per 10,000 recruits. A program to address HRI was 
adopted in 1954 and later modified in 1956. Minard reported a lower 
mean weekly HRI rate with the enhanced interventions in 1956 (4.7 per 
10,000 recruits) compared to the initial intervention in 1955 (12.4 per 
10,000 recruits), despite higher temperatures in 1956. Initial 
interventions included curtailing physical activity during high heat 
and numerous behavioral changes, such as modifications to uniforms and 
leadership training; while the most substantial changes to enhance the 
interventions included curtailing physical activity based on WBGT and 
differentiating physical activity guidance for acclimatized versus 
unacclimatized recruits. Later enhancements to the intervention 
included conditioning recruits with substandard fitness, shade for 
outdoor classrooms, cooling for indoor classrooms, modification of the 
clothing policy to allow for only t-shirts, light duty status for 
recently vaccinated recruits, one hour rest or classroom instruction 
after meals, better ventilation in barracks to improve sleep, and 
strategies to increase water and salt intake. The mean weekly HRI rate 
for all summers with the enhanced intervention (1956-1960) was 4.3 per 
10,000 recruits. Four fatalities from heat stroke occurred from 1951 to 
1953, but no fatalities occurred since 1953.

[[Page 70763]]

C. Conclusions for Multicomponent Interventions in Civilian and 
Military Employees
    In conclusion, three studies in civilian worker populations found 
that multicomponent heat stress interventions reduced the incidence of 
HRI claims and self-reported heat strain and dehydration symptoms and 
increased work output. The findings of these studies are supported by 
studies among military personnel, which also found multicomponent 
interventions to be effective in reducing incidence of HRI, as well as 
data on the effectiveness of individual control measures reported in 
laboratory and experimental studies, which are summarized above. The 
findings of these multicomponent intervention studies are summarized in 
table V-3.

  Table V-3--Summary of Evidence of the Effectiveness of Multicomponent
        Interventions in Reducing HRIs and Heat-Related Symptoms
------------------------------------------------------------------------
                Evidence                              Notes
------------------------------------------------------------------------
                      Multi-component Interventions
------------------------------------------------------------------------
McCarthy et al. (2019): In a comparison   The program involved
 of heat-related illness claims before    medical monitoring and
 and after the implementation of a heat   training.
 stress awareness program that began in   Recommendations made
 2011 in a Texas municipality, the        to supervisors included
 average annual rate of HRI claims fell   unlimited access to water,
 [by 37%] in 2012-2014 (16 claims/1,000   sports drinks, and shade, as
 workers) and [by 96%] in 2015-2017 (1    well as establishing
 claim/1,000 workers) compared to the     acclimatization schedules,
 pre-intervention period (25.5 claims/    work/rest procedures, and
 1,000 workers).                          first aid protocols.
                                          It is not known if and
                                          to what extent recommendations
                                          were implemented.
Perkison et al. (2024). The program in    The study authors
 Texas municipality workers reported by   concluded ``medical
 McCarthy et al. (2019) was modified in   surveillance may be an
 2017 to include only training and        important component in
 acclimatization, and no longer include   lowering workforce heat-
 medical surveillance. Rate of heat-      related illness,'' but noted
 related illness did increase after       the small sample size and
 these changes (to 7.6 claims/1,000       short evaluation period.
 workers) but remained [70%] lower than
 when no program was implemented.
Bodin et al. (2016) reported that three   Most of the
 months after implementation of           interventions were consistent
 interventions, self-reported heat        with the main interventions of
 stress and dehydration-associated        the proposed standard (i.e.,
 symptoms decreased as follows: feeling   providing drinking water, and
 feverish (40% to 10% [[darr]76%]),       shaded rest breaks and a lunch
 exhaustion (37% to 14% [[darr]62%]),     break).
 nausea (35% to 12% [[darr]66%]), very    Ergonomic improvements
 dry mouth (49% to 26% [[darr]46%]),      were also implemented.
 very little urine (37% to 19% [[darr]    Non-U.S. workers (El
 49%]), cramps (30% to 17%                Salvador) in sugar cane
 [[darr]45%]), diarrhea (14% to 0%        industry.
 [[darr]100%]), disorientation (12% to
 0% [[darr]100%]), and fainting (4.7%
 to 2.4% [49%]) Rates of vomiting and
 dysuria were similar.
Kerstein et al. (1986) reported a [54%]   Military study.
 decrease in heat illnesses in military   Intervention: A
 reservists after an intervention.        lecture on water as
                                          prevention, training on and
                                          use of portable WBGT monitors,
                                          and a special briefing for
                                          Commanding Officers.
Stonehill and Keil (1961) reported the    Military study.
 number of heat stroke cases and the      Intervention being
 number of troops in the summers of       tested: In addition to
 1957 and 1958, before and after          existing prevention measures,
 additional protective measures were      they added increased water and
 implemented.                             salt tablet availability,
 The heat stroke rate in summer   removing fatigue shirts inside
 1958 after implementing additional       classrooms, using WBGT to
 protective measures was [95%] lower      determine when to pause
 [0.05/1,000 troops] than the summer      training, and avoiding intense
 before [0.87/1,000 troops].              outdoor training in the first
                                          week of training.
Minard (1961) study of military           Military study.
 recruits:                                Examples of
 The rate of HRI after            intervention measures:
 implementation of the program (12.4/     curtailing physical activity
 10,000 recruits) was [77%] lower than    during high heat,
 before the program was implemented (53/  modifications to uniforms,
 10,000) recruits.                        leadership training,
 The rate of HRI after enhanced   curtailing physical activity
 interventions (4.7 per 10,000            based on WBGT, differentiating
 recruits) was [62%] lower than the       physical activity guidance for
 rate after initial interventions (12.4   acclimatized versus
 per 10,000 recruits) and [91%] lower     unacclimatized recruits,
 than the period before the program (53/  conditioning recruits with
 10,000).                                 substandard fitness, shade for
                                          outdoor classrooms, cooling
                                          for indoor classrooms,
                                          modification of the clothing
                                          policy to allow for only t-
                                          shirts, light duty status for
                                          recently vaccinated recruits,
                                          one hour rest or classroom
                                          instruction after meals,
                                          better ventilation in barracks
                                          to improve sleep, and
                                          strategies to increase water
                                          and salt intake.
------------------------------------------------------------------------
Numbers in brackets calculated and rounded by OSHA.

V. Governmental and Non-Governmental Organizations' Requirements and 
Recommendations
    A number of governmental and non-governmental organizations 
recommend or require heat injury and illness prevention programs or 
multiple controls to address risks related to occupational heat 
exposure. This shows that OSHA's proposal continues to reflect the 
growing consensus that HRIs can be avoided or minimized when employers 
address conditions that have been shown to increase the risk of HRI. 
OSHA's proposal also continues to reflect a consensus that, to be most 
effective, an HRI prevention program should incorporate multiple 
interventions.
A. Governmental Requirements and Recommendations
    As of April 2024, five States had heat injury and illness 
prevention standards, reflecting a recognition by these States that 
certain measures can reduce heat-related risks posed to workers. These 
standards have many of the same types of controls OSHA is proposing 
(e.g., a written heat safety plan, emergency response protocols, rest 
breaks, training on HRI recognition and prevention). For a more 
detailed discussion of existing State standards see Section III., 
Background. In addition, numerous States have published heat illness 
and injury prevention guidance for workers.
    NIOSH has issued a number of guidance products and provided expert

[[Page 70764]]

advice on heat injury and illness prevention and developed a 
programmatic approach to reduce the risks associated with heat for 
workers. For example, in 2016, NIOSH updated its Criteria for a 
Recommended Standard: Occupational Exposure to Heat and Hot 
Environments, first published in 1972 and updated in 1986, stating, 
``compliance with this recommended standard should prevent or greatly 
reduce the risk of adverse health effects to exposed workers.'' NIOSH 
recommends that employers ``establish and implement a written program 
to reduce exposures to or below the applicable RAL or REL'' (which 
considers exposure to environmental heat and metabolic heat (i.e., work 
intensity) for unacclimatized and acclimatized employees, respectively) 
with engineering and work practice controls. Examples of engineering 
controls include ventilation to increase air movement, air-
conditioning, screening, and insulation. Examples of administrative 
controls include rest breaks to decrease exposure time and metabolic 
heat loads, increasing distance from radiant sources, and implementing 
acclimatization protocols, health and safety training, medical 
screening for heat intolerance, and a heat alert program. If 
engineering and administrative controls do not reduce exposure below 
the applicable RAL or REL, NIOSH also recommends cooling clothing/PPE. 
NIOSH states, ``the reduction of adverse health effects can be 
accomplished by the proper application of engineering and work practice 
controls, worker training and acclimatization, measurements and 
assessment of heat stress, medical monitoring, and proper use of heat-
protective clothing and personal protective equipment (PPE)'' (NIOSH, 
2016).
    In another example of NIOSH guidance, NIOSH investigated a number 
of heat-related workplace fatalities to assess the hazards and propose 
recommendations for preventing similar fatalities, as part of the 
Fatality Assessment and Control Evaluation (FACE) Program. In four heat 
fatality investigations that affected landscapers (NIOSH, 2015), farm 
workers (NIOSH, 2007), firefighters (NIOSH, 1997), and construction 
laborers (NIOSH, 2004), collective recommendations related to heat 
included: development, implementation and training on a safety and 
health program that is made available to all workers; providing rest 
breaks and accessible hydration; training workers and supervisors on 
recognizing HRI; providing prompt medical assistance for HRI; 
monitoring of worker symptoms by supervisors; implementing 
acclimatization programs; informing workers of drinks (e.g., alcoholic) 
that can increase risk; having medical providers inform workers taking 
certain drugs or with certain medical conditions of their increased 
risk; and factoring in clothing and weather to determine firefighter 
workloads.
    Additionally, there is a recognition amongst other Federal 
regulatory agencies that employers can implement control measures to 
reduce heat-related risks and harms. The Mine Safety and Health 
Administration (MSHA) first published heat guidance for mines in 1976, 
and most recently published ``Heat Stress in Mining'' which provides 
guidance on reducing heat stress (MSHA, 2012). The report states that a 
combination of engineering controls, administrative controls and work 
practices, and PPE can reduce heat and prevent employee's core 
temperatures from rising. MSHA recommendations include mine planning to 
provide cool rest areas, implementing exhaust ventilation and air-
conditioning in mines, using canopies in the sun, using skillful 
blasting procedures to reduce excessive heat, using automation/remote 
controls to reduce metabolic heat, implementing work-rest regimens with 
frequent breaks, pacing work tasks, performing heavy tasks in cooler 
areas or at cooler times, rotating personnel through hot work tasks, 
providing readily accessible, cooler rest areas and drinking water, 
acclimatizing new and returning employees, and ensuring employees and 
supervisors are knowledgeable about heat related topics such as risk, 
prevention, and symptoms.
    In 1993, the EPA published ``A Guide to Heat Stress Management in 
Agriculture'' to ``help private and commercial applicators and 
agricultural employers protect their workers from heat illness'' (EPA, 
1993). The guide outlines the development of a basic program to control 
heat stress which includes: designating one person to manage the heat 
stress program; training workers and supervisors on heat illness 
prevention; acclimatizing workers when they begin to work under hot 
conditions; evaluating weather conditions, workload, necessary 
protective equipment or garments, and the physical condition of the 
employee; managing work activities by setting up rest breaks, rotating 
tasks among workers, and scheduling heavy work for cooler hours; 
establishing a drinking water program; taking additional measures such 
as providing special cooling garments, shade or air-conditioned mobile 
equipment; and giving first aid when workers become ill (EPA, 1993).
    In 2023, the U.S. Army updated its Training and Doctrine Command 
(TRADOC) Army Regulation 350-29 which ``prescribes policy and provides 
guidance to commanders in preventing environmental (heat or cold) 
casualties.'' It includes requirements for rest in shade and water 
consumption according to specific WBGT levels and work intensity, and 
consideration of heat stress when planning training events (Department 
of the Army, June 15, 2023). In 2022, the U.S. Department of the Army 
issued the technical heat stress bulletin ``TB MED 507: Heat Stress 
Control and Casualty Management'' that contains measures to prevent 
indoor and outdoor HRIs in soldiers, with recommendations for 
acclimatization planning, work-rest cycles, fluid and electrolyte 
replacement, and cooling methods (e.g., shade, fans for prevention, and 
iced sheets and ice water immersion for treatment) (Department of the 
Army, April 12, 2022).
    The U.S. Department of the Navy has published additional guidance 
on heat injury and illness prevention particular to naval conditions 
(Department of the Navy, 2023). When Navy personnel are ``afloat'', 
they use Physiological Heat Exposure Limits (PHEL) curves to manage 
heat stress based on exposure limits/stay times for acclimatized 
personnel under various conditions of environmental heat and work 
intensity. The PHEL curves were designed to allow core body temperature 
to rise to 102.2 [deg]F (39 [deg]C) among healthy and acclimatized 
individuals who have rested and recovered from prior heat exposures.
    In 2023, the Heat Injury and Illness Prevention Work Group of the 
National Advisory Committee on Occupational Safety and Health (NACOSH) 
presented to OSHA recommendations on potential elements of a proposed 
heat injury and illness prevention standard. The Work Group recommended 
that OSHA include the following measures in a potential standard: a 
written exposure control plan (heat illness prevention plan); training 
on heat illness prevention; environmental monitoring; provision of 
water, breaks, and shade or cool-down areas; other administrative 
controls (e.g., rotating workers through work tasks and implementing a 
communication system for regular check-ins); other engineering control 
measures (e.g., ventilation, exhaust fans, and portable cool-down 
mechanisms including fans, tents, shielding/

[[Page 70765]]

insulation, proactive misting); workplace practice controls (e.g., 
providing coolers with ice and scheduling work during the coolest part 
of day); personal protective equipment; acclimatization procedures; 
worker participation in planning activities; and emergency response 
procedures (NACOSH, May 31, 2023).
B. National Non-Governmental Organizations
    ACGIH first recommended a standard for heat stress in 1971 (ACGIH, 
2021), and most recently updated it in 2023 (ACGIH, 2023). The TLV is a 
value that is determined with the goal of maintaining thermal 
equilibrium for healthy acclimatized employees and is based on WBGT 
adjusted for work intensity and clothing/PPE. An action limit (AL) 
considers those same factors for unacclimatized employees. ACGIH 
recommends that whenever heat stress among workers is suspected (based 
on factors such as environmental conditions, work demands, work-rest 
patterns, and acclimatization states), employers have a Heat Stress 
Management Program (HSMP) that includes written plans for ``General 
Controls'' and as appropriate, ``Job Specific Controls'' (Table 5 of 
the Heat Stress and Strain section of the TLV Booklet). ACGIH states 
``The principal objective of a HSMP is the prevention of excessive heat 
strain among workers that may result in heat-related disorders.'' 
General controls include environmental surveillance, medical clearance 
and counseling by a healthcare provider, training, acclimatization 
planning, fluid replacement, symptom monitoring, breaks in the shade, 
and an emergency response plan. Job specific controls include 
engineering controls (e.g., air movement, shade, radiant heat shields), 
administrative controls (e.g., limiting exposure time and allowing for 
enough recovery time), personal cooling, and physiological monitoring.
    In 2024, the American National Standards Institute/American Society 
of Safety Professionals A10 Committee (ANSI/ASSP) released the American 
National Standard A10.50 Standard for Heat Stress Management in 
Construction and Demolition Operations. The voluntary consensus 
standard ``establishes procedures for the management of heat stress 
hazards and the selection and use of appropriate controls and practices 
to reduce risks presented by heat stress and prevention of heat 
illnesses for all work environments.'' The standard recommends that 
employers develop and implement the following: heat stress management 
program; acclimatization plan; workplace surveillance/risk assessment; 
provision of water and sodium electrolyte supplements; provision of 
rest breaks and shaded break locations; buddy system; first aid and 
emergency action plan; medical surveillance; employee participation; 
implementation of heat stress controls including engineering controls 
such as air-conditioning, radiant heat control (barrier), convection 
controls (cooling), evaporative controls such as misting fans, and 
metabolic controls (e.g., mechanical equipment or tools to reduce 
metabolic demands of work tasks); administrative controls such as 
scheduling for cooler times and allowing self-paced work; personal 
protective equipment; and training on heat illness prevention (ANSI/
ASSP, 2024). More specific recommendations (e.g., frequency of rest 
breaks; monitoring employees) are provided when certain triggers are 
exceeded.
    In 2021, the American Society for Testing and Materials (ASTM) 
finalized its Standard Guide for Managing Heat Stress and Heat Strain 
in Foundries (E3279-21) which establishes ``best practices for 
recognizing and managing occupational heat stress and heat strain in 
foundry environments.'' The standard outlines employer responsibilities 
and recommends elements for a `Heat Stress and Heat Strain Management 
Program.' Employer responsibilities include evaluating temperature and 
issuing heat alerts; ensuring control measures are in place; and 
reviewing heat exposure incidents to implement corrective actions. 
Program elements include worker preparation (i.e., only assigning 
workers to tasks involving heat exposure ``who are prepared for work in 
those environments and can tolerate the heat exposure associated with 
the assignments'') and workplace and work preparation (i.e., 
implementing controls that reduce heat stress through process heat 
emission control and ventilation of work areas, adjusting work 
schedules, providing heat relief crews (e.g., crew rotation), providing 
personal protective equipment, employing personal and portable cooling 
devices, providing readily available water, and providing cooled 
location for work break) (ASTM, 2021). The standard also recommends 
employers and workers monitor heat strain and establish emergency 
response protocols.
C. Conclusion on Governmental and Non-Governmental Recommendations
    In closing, a number of governmental and non-governmental groups 
have either promulgated regulations or published recommendations for 
protecting workers from HRI. Many of those regulations or 
recommendations contain components that are consistent with protections 
in the proposed rule, including plans to prevent heat stress, rest 
breaks in shaded or cooled areas, cool drinking water, ventilation or 
cooling methods (e.g., fans exhaust), acclimatization, observation of 
symptoms in workers, environmental monitoring, and emergency response 
procedures. Many of these protections have been recognized for decades 
as being effective in reducing the risk of HRI in workers. This shows 
that OSHA's proposal continues to reflect the growing consensus that 
HRIs can be avoided or minimized when employers address conditions that 
have been shown to increase the risk of HRI and incorporate these 
protections as part of a program that is tailored to each workplace.
VI. Conclusion
    OSHA reviewed a number of studies that provided quantitative 
evidence of the effectiveness of multi-component interventions in 
reducing heat-related illness or HRI; the results of those studies are 
summarized in table V-3 above. Studies among Texas municipality 
employees show that a multi-component intervention approach reduced HRI 
claims by 37 to 96 percent compared to pre-intervention levels, 
depending on the period of intervention and the types of interventions 
applied (McCarthy et al., 2019; Perkison et al., 2024). Implementation 
of multi-component interventions in military studies resulted in 
slightly lower reductions in HRI from pre- to post-intervention (54-95 
percent), again depending on the types of interventions applied in 
different implementation periods (Kerstein et al., 1986; Minard, 1961; 
Stonehill and Keil, 1961).
    OSHA acknowledges that several of the interventions implemented 
among the Texas municipality employees and military personnel differ 
from the interventions in the proposed standard. However, interventions 
focusing on water, rest, and shade among sugar cane employees in El 
Salvador resulted in similar reductions for several common (i.e., 
occurring in 30% or more of employees pre-intervention) symptoms of 
heat-related illness (e.g., 45% reduction in cramps, 46% reduction in 
very dry mouth, 49% reduction in very little urine, 62% reduction for 
exhaustion, 66% reduction for nausea, 76% reduction for feeling 
feverish) (Bodin et al., 2016; communication with David Wegman, 
November 2023). Because of the small number of workers completing the 
study (n=41), results

[[Page 70766]]

regarding less common symptoms (reported in less than 15% of workers 
pre-intervention) are more uncertain, but Bodin et al. reported a 
decrease in fainting and no incidents of diarrhea or disorientation 
after the interventions were implemented. Therefore, the study by Bodin 
et al. (2016) supports the finding that a multi-intervention approach 
that includes several interventions in common with the proposed 
standard is likely to result in substantial reductions in HRI symptoms.
    Despite several limitations that were acknowledged for these multi-
intervention studies, the results for all are of a large magnitude and 
consistently show effectiveness for multi-component interventions in 
preventing HRIs. In addition, the results are mechanistically supported 
by experimental studies showing the effectiveness of individual 
interventions in preventing signs and symptoms related to heat strain. 
OSHA finds the studies looking at multi-component approaches to be more 
relevant for looking at quantitative reductions in HRI because each 
individual component would contribute to the overall effect.
    In addition to studies showing effectiveness of multi-component 
interventions in preventing HRIs, two studies also show that effective 
treatments are available to prevent death if heat stroke does occur. As 
reported in more detail under the Explanation of Proposed Requirements 
for paragraph (g)(3), Heat illness and emergency response and planning, 
studies examining the effectiveness of treating individuals suffering 
from exertional heat stroke reported 99.8% survival in military 
personnel treated with ice sheets (bed sheets soaked in water) (DeGroot 
et al., 2023) and 100% survival in marathon runners doused with cold 
water and massaged with ice bags (McDermott et al., 2009a).
    OSHA preliminarily finds that the totality of the evidence reviewed 
supports that the approach outlined in the proposed standard, which 
consists of a heat injury and illness prevention plan and the 
application of multiple control measures, will result in a substantial 
reduction in HRIs (range: 37-96%) and heat-related fatalities (range: 
99.8-100%) in employees who would be covered under the proposed 
standard.
VII. Requests for Comments
    For the controls proposed, OSHA requests information and comment on 
the following questions and requests that stakeholders provide any 
relevant data, information, or additional studies (or citations) 
supporting their view, and explain the reasoning or recommendations for 
including such studies:
     OSHA recognizes that a number of States (e.g., California, 
Oregon, Washington) have implemented standards to prevent HRIs and 
heat-related fatalities among workers. OSHA is aware that there are 
existing and emerging data on the efficacy of the State standards in 
preventing and reducing HRIs and heat-related fatalities. OSHA welcomes 
proposed analytical methods or analyses of existing data (see e.g., 
discussion in V.A., Risk Assessment of existing data sources, 
www.dir.ca.gov/dosh/reports/State-OSHA-Annual-Report-(SOAR)-FY-
2022.pdf) or unpublished data that may be used to estimate the effects 
of these State standards on heat-related injury, illness, and fatality 
rates among workers. OSHA is also interested in comments on how to 
account for the differences (some of which are significant) between the 
State standards and OSHA's proposed standard in estimating efficacy of 
OSHA's proposed standard. Are there studies, data, or other evidence 
that demonstrate the efficacy of and/or describe employers' or workers' 
experiences with these heat-specific State standards?
     Has OSHA adequately identified and documented the studies 
and other information relevant to its conclusion regarding the 
effectiveness of these controls in reducing heat strain and the risk of 
HRIs, and are there additional studies OSHA should consider?
     Are there additional studies or evidence available that 
identify appropriate frequencies and durations of rest breaks for 
reducing heat strain and risk of HRIs?
     Are OSHA's conclusions about the effectiveness of controls 
in preventing HRI reasonable?

VI. Significance of Risk

    As explained in Section II., Pertinent Legal Authority, prior to 
the issuance of a new standard, OSHA must make a threshold finding that 
a significant risk of material harm exists, and that issuance of the 
new standard will substantially reduce that risk.
    In Section IV., Health Effects, OSHA presents data and information 
demonstrating the range of heat-related injuries and illnesses (HRIs) 
that can be caused by occupational exposure to heat. This discussion 
demonstrates that HRIs often result in material harm, as they are 
potentially disabling, can result in lost work time, require medical 
treatment or restricted work, and in certain cases, can lead to death. 
In Section V., Risk Assessment, OSHA presents the best available 
evidence on the risk of incurring these heat-related material health 
impairments among workers in the U.S., which clearly demonstrates that 
there exists a significant risk of material harm to workers from 
occupational exposure to heat. As OSHA's analysis of BLS data shows, 
there was an average of 40 heat-related deaths (2011-2022) and 3,389 
HRIs involving days away from work (2011-2020) among U.S. workers per 
year. Additionally, based on OSHA's review of workers' compensation 
claim data, OSHA found that workers in sectors and industries where 
they are likely exposed to heat in their job (and therefore are more 
likely to be covered by this standard) have far higher estimated 
incidence of HRI than the national average, indicating that the risk to 
heat-exposed workers is much higher than nationwide data suggests. 
Furthermore, both the annual and working lifetime incidence rates 
underestimate the true risk for heat-exposed workers given 
underreporting of workplace injuries and illnesses. Thus, as explained 
in sections A and B below, OSHA preliminarily determines that a 
significant risk of material harm from occupational exposure to 
hazardous heat exists, and issuance of this standard would 
substantially reduce that risk.

A. Material Harm

    As discussed in Section IV., Health Effects, the risks posed by 
exposure to workplace heat hazards are significant and can result in 
serious HRIs or even death. As discussed in Section IV.B., General 
Mechanisms of Heat-Related Health Effects, heat stress can result in 
increased core body temperature and blood flow being shunted towards 
the skin and away from major organs (e.g., brain, liver, kidneys) and 
muscles. Sweating, which is a healthy and normal response to heat 
stress, can also contribute to a reduction in circulating blood volume 
if fluids are not adequately replaced. This increase in core body 
temperature and reduced blood flow can lead to health effects like heat 
stroke, heat exhaustion, heat syncope, and rhabdomyolysis. If not 
treated promptly, heat stroke can cause permanent organ damage and lead 
to death. Treatment often requires hospitalization and time away from 
work (see discussion in Section IV.E., Heat Stroke). Other health 
effects, such as heat exhaustion, may also require time away from work 
if recommended by a medical professional. Many heat-related health 
effects, such as heat cramps and heat exhaustion, can impair

[[Page 70767]]

a worker's functional capacity while on the job. Heat syncope can pose 
additional dangers to workers if they are in precarious work 
environments, such as on rooftops or while operating machinery. Heat 
exhaustion can also rapidly progress to heat stroke if not recognized 
and treated early. As discussed in Section IV.P., Heat-Related 
Injuries, heat-induced impairments in functional capacity on the job 
can lead to traumatic injuries, which are more likely to occur on hot 
days.
    The studies that OSHA relied on in Section V.A., Risk Assessment 
leverage data from multiple surveillance databases (e.g., BLS SOII, 
workers' compensation claims databases, and hospital discharge data) 
that have inclusion criteria that OSHA preliminarily concludes would 
clearly indicate that captured cases of HRIs represent material 
impairment of health. For example, the estimated number of work-related 
HRIs reported in the BLS SOII capture only those that involved days 
away from work (Note: For 2021-2022 biennial data, SOII additionally 
reports cases involving job restriction or transfer). Similarly, 
hospital discharge datasets would represent only cases that involved an 
emergency department visit and/or inpatient hospitalization. While 
workers' compensation eligibility varies, all of the claims would 
involve either a visit with a medical professional and/or lost 
worktime. HRIs resulting in lost work time and/or the need for medical 
care beyond first aid clearly constitute material harm.
    However, HRIs constituting material harm are not limited to those 
rising to the level of lost work time and/or the need to seek care from 
a medical professional. Based on the evidence discussed in this and 
other sections of this preamble, OSHA has preliminarily concluded that 
many of the HRIs associated with workplace exposure to heat hazards 
constitute material harm, even if they are not captured in the 
databases OSHA relied on in its risk assessment. OSHA recognizes that 
many of these HRIs may be reversible, particularly if early 
intervention is provided. Nonetheless, OSHA presents evidence in 
Section IV., Health Effects that these HRIs can be debilitating. In 
addition to lost work time and the need for treatment by a medical 
professional, HRIs can cause reduction or loss of the worker's normal 
functional capacity in work tasks and loss of productivity. 
Additionally, where preventive action or early treatment is not 
provided, these disorders can rapidly progress to more serious 
conditions, and have the potential to result in permanent damage to 
organs, causing short-, medium-, and long-term health effects, or 
death. Thus, while some of the health effects OSHA has identified may 
not rise to the level of material harm in all cases, the agency 
believes that each can be material in severe cases.

B. Significant Risk

    Peer-reviewed studies and State or national statistics are 
available to demonstrate the high incidence of work-related HRIs 
occurring among workers exposed to heat hazards at work. Estimates of 
the risk of harm confronting exposed workers can be based directly on 
the rates of work-related HRIs currently being reported.
    In Section V.A., Risk Assessment, of this preamble, OSHA evaluated 
the risk to workers of a heat-related injury, illness, or fatality. 
OSHA's analysis of BLS data indicated an annual average of 40 heat-
related deaths (2011-2022) and 3,389 HRIs involving days away from work 
(2011-2020) among U.S. workers. These annual heat-related death and HRI 
numbers alone clearly constitute a significant risk and are in line 
with OSHA's significant risk findings in previous safety standards 
(see, e.g., Confined Spaces in Construction, 80 FR 25366, 25371 (May 4, 
2014); Electric Power Generation, Transmission, and Distribution; 
Electrical Protective Equipment, 79 FR 20316, 20321-20322 (April 11, 
2014); Cranes and Derricks in Construction, 75 FR 47906, 47913 (Aug. 9, 
2010)). However, as discussed in Section V.A., Risk Assessment, many of 
the sources that OSHA reviewed reported HRI data in terms of incidence 
rates, and OSHA has considered these rates in assessing significant 
risk, to the extent they capture populations that are actually exposed 
to hazardous occupational heat.
    Unfortunately, the available data is insufficient to precisely 
estimate the risk to only workers who are exposed to hazardous 
occupational heat. But by examining incidence estimates derived from 
various datasets, including State workers' compensation systems, OSHA 
was able to determine a range of HRI incidence rates among workplaces 
where employees are likely to be exposed to heat in their job. In 
Section V.A., Risk Assessment, OSHA identified various sector incidence 
estimates of HRI over a working lifetime (i.e., 45 years), including: 
234 to 1,737 cases per 100,000 workers in agriculture, forestry, 
fishing, and hunting; 63 to 545 cases per 100,000 workers in 
construction; 131 to 396 cases per 100,000 workers in administrative 
and support and waste management and remediation services; 49.5 to 171 
cases per 100,000 workers in transportation and warehousing; and 513 
cases per 100,000 workers in utilities, among others. The working 
lifetime incident rates were even higher in specific industries, such 
as an estimated 3,479 cases of HRI per 100,000 workers for farm labor 
contractors and crew leaders and 2,439 cases per 100,000 structural 
steel and precast concrete workers over a working lifetime of 45 years 
(see Section V. A., Risk Assessment, table V-1). OSHA preliminarily 
concludes that these incidence rates, though as explained below 
substantially underestimate actual risk, are the best available 
evidence and sufficient to make a finding of significant risk of HRIs 
among workers who are exposed to occupational heat.
    While the data are not sufficient to develop a single point 
estimate of the risk posed to heat-exposed workers, OSHA has 
preliminarily determined that the available data from BLS and workers' 
compensation claims support an estimate of working lifetime risk of HRI 
ranging from 135 cases per 100,000 workers (calculated based on the BLS 
average estimated annual incidence of HRIs for all workers for 2011-
2020) to 3,479 cases per 100,000 workers (based on workers' 
compensation claims). Even the lowest estimate within this range 
exceeds the 1/1000 threshold that OSHA has historically found to 
clearly constitute a significant risk.
    As noted above, OSHA believes that these data from BLS and workers' 
compensation claims substantially understate the true risk to workers. 
For one, the inclusion criteria for the surveillance systems used to 
estimate incidence would exclude a large proportion of HRI cases. For 
instance, prior to this year, the BLS SOII only reported the estimated 
number of HRIs that involved days away from work, which may be less 
than 50% of all OSHA-recordable work-related HRIs (see, e.g., BLS, IIF 
Latest Numbers for 2022, https://www.bls.gov/iif/latest-numbers.htm). 
Additionally, the majority of incidence estimates identified by OSHA 
are based on the risk of HRIs confronting an entire working population 
(e.g., all workers in a particular industry or sector), both exposed 
and non-exposed. Clearly, the risk of experiencing a work-related HRI 
is considerably higher among the subset of workers exposed to heat 
hazards in their jobs than it is for the rest of the working 
population. For example, the annual BLS incidence estimates are 
susceptible to understating risk in this way because when BLS 
calculates annual incidence estimates, it captures the entire U.S. 
workforce in the denominator, which includes a large

[[Page 70768]]

number of unexposed workers (e.g., office workers in climate-controlled 
buildings). Consequently, the working lifetime risk of HRI estimate 
based on BLS's annual incidence estimates (i.e., 135 cases per 100,000 
workers), also substantially underestimates the true risk for heat-
exposed workers. There is also a large body of literature demonstrating 
the general underreporting of work-related injuries and illnesses, the 
findings of which OSHA believes would also apply to HRIs. See Section 
V.A., Risk Assessment, for additional discussion of underreporting of 
heat-related fatalities and HRIs.
    As discussed in Section V.C., Risk Reduction, dozens of peer-
reviewed studies and multiple authoritative bodies (e.g., NIOSH, ACGIH, 
ANSI/ASSP) indicate that the provisions outlined in this proposed rule 
would, if promulgated, substantially reduce risk to workers. A large 
body of data demonstrates that workplace interventions--such as rest 
breaks, cool drinking water, acclimatization, shade, and fans--can be 
very effective in reducing heat strain, which is responsible for 
causing HRIs. This reduction in heat strain and/or reduction in HRI 
risk has been shown in studies that have examined the impact of 
interventions in an experimental setting, as well as studies that have 
documented reductions in HRI prevalence following the implementation of 
heat injury and illness prevention measures. OSHA preliminarily 
concludes that implementation of the proposed standard will result in a 
substantial reduction in HRIs (range of estimates: 37-96%) and heat-
related fatalities (range of estimates: 99.8-100%) in employees who 
would be covered under the proposed standard.

C. Preliminary Conclusions

    OSHA preliminarily concludes that HRIs associated with workplace 
exposure to heat hazards constitute material harm. Further, based on 
the evidence discussed in this section, the agency preliminarily 
concludes that heat-exposed workers are at significant risk of 
experiencing a work-related HRI or heat-related death, and compliance 
with the proposed standard would substantially reduce that risk.

VII. Explanation of Proposed Requirements

A. Paragraph (a) Scope and Application

    Paragraph (a) establishes the scope of the proposed standard. 
Paragraph (a)(1) would require all employers subject to OSHA's 
jurisdiction--including general industry, construction, maritime, and 
agriculture--to comply with the proposed requirements, subject to the 
exemptions in proposed paragraphs (a)(2) and (3). The scope of the 
proposed standard applies to a wide range of sectors that include both 
indoor and outdoor work areas. The proposed standard aims to provide 
protections while accounting for the different work areas, anticipated 
exposures, and other conditions in these sectors.
    Paragraph (a)(2) describes the exemptions for the proposed standard 
based on work activities. Employers would be responsible for 
determining which work activities are covered by the standard. Although 
an employer may have some work activities exempt from the proposed 
standard, other activities may be covered (except for organizations 
whose primary function is the performance of firefighting. See the 
discussion of paragraph (a)(2)(iii) below). Under paragraph (a)(3), if 
an employer's employees exclusively perform the work activities in 
paragraphs (a)(2)(i) through (vi), then that employer would be exempt 
from this proposed standard.
    Paragraph (a)(2)(i) would exclude work activities for which there 
is no reasonable expectation of exposure at or above the initial heat 
trigger. This exception recognizes that some workplaces would not 
reasonably be expected to reach or exceed the initial heat trigger 
(e.g., because of their location and/or seasonal variations in 
temperature). This exclusion may apply to work activities such as 
operating seasonal businesses outdoors (e.g., during winter months), 
when temperatures are lower than the initial heat trigger. For 
instance, if a business that exclusively operates an outdoor holiday 
market during the winter season in a location where daily high 
temperatures are always below the initial heat trigger, this standard 
would not apply to work activities performed at that market.
    Paragraph (a)(2)(ii) would exclude short duration employee 
exposures at or above the initial heat trigger of 15 minutes or less in 
any 60-minute period. OSHA has preliminarily concluded that 
intermittent exposures within this duration are not likely to 
significantly raise core body temperature and result in heat-related 
injuries and illnesses (HRIs). Numerous studies (many described in 
Section V.C., Risk Reduction) evaluated the effect of hotter 
temperatures on participants' core body temperatures under various 
scenarios (e.g., clothing type, level of activity, work/rest periods, 
acclimatization status) of different durations. Overall, evidence 
suggests that heat exposure of 15 minutes or less does not tend to 
cause an elevation of at least 1 [deg]C (1.8 [deg]F) in participants' 
core body temperatures, which would be indicative of potential heat 
stress (McLellan & Selkirk, 2006; Meade et al., 2016b; Lamarche et al., 
2017; Seo et al., 2019; Kaltsatou et al., 2020; Notley et al., 2022a; 
Notley et al., 2022b).
    This exemption recognizes that while typical work activities may 
take place below the initial heat trigger, employees may experience 
short exposures to heat at various times during their shift. For 
example, an employer who is otherwise exempt from the standard but has 
employees who occasionally walk to collect mail outside in temperatures 
at or above the initial heat trigger for 15 minutes or less in any 60-
minute period, would still be exempt. This exemption is consistent with 
the scope exemptions of Colorado, Washington, and Oregon's State 
standards (7 Colo. Code Regs. section 1103-15:3 (2023); Wash. Admin. 
Code 296-307-09710 (2023); Or. Admin. R. 437-002-0156 (2024)).
    In addition, in order for this exemption to apply for employees 
whose work activities are primarily performed in air-conditioned 
vehicles, employers must ensure employees are not exposed to 
temperatures at or above the initial heat trigger for more than 15 
minutes in any 60-minute period. For instance, where an employee who 
drives an air-conditioned vehicle repeatedly exits the vehicle to 
deliver product in temperatures at or above the initial heat trigger, 
this activity would only be exempt from the standard if cumulative 
exposure in any 60-minute period at or above the initial heat trigger 
is for 15 minutes or less. If delivery tasks, such as unloading product 
from the vehicle and moving product to its destination, occur at or 
above the initial heat trigger for more than 15 minutes in any 60-
minute period, these work activities would be covered by the standard.
    Paragraph (a)(2)(iii) would exclude organizations whose primary 
function is the performance of firefighting. It would also exclude 
emergency response activities of workplace emergency response teams, 
emergency medical services (EMS), or technical search and rescue; \4\ 
and any emergency response

[[Page 70769]]

activities already covered under 29 CFR 1910.120, 1910.146, 1910.156, 
part 1915, subpart P, 1926.65, and 1926.1211. Fire departments, 
workplace emergency response teams, EMS, and technical search and 
rescue are covered by OSHA's proposed Emergency Response standard (89 
FR 7774, Feb. 5, 2024), which would replace the existing Fire Brigades 
standard, 29 CFR 1910.156. The update to 29 CFR 1910.156 would expand 
coverage from only fire brigades, industrial fire departments, and 
private or contractual type fire departments, to include protections 
for all employees who perform firefighting, EMS, or technical search 
and rescue, as part of their regularly assigned duties as well as 
employees who are members of a workplace emergency response team. If 
the Emergency Response standard is finalized before this proposed 
standard, OSHA intends to revise this exemption to reflect the updated 
29 CFR 1910.156.
---------------------------------------------------------------------------

    \4\ ``Technical search and rescue'' refers to a type of 
emergency service that utilizes special knowledge and skills and 
specialized equipment to resolve unique or complex search and rescue 
situations, such as rope rescue, vehicle/machinery rescue, 
structural collapse, trenches, and technical water rescue. OSHA 
intends the phrase to have the same meaning as used in the proposed 
Emergency Response standard (see 89 FR 7804).
---------------------------------------------------------------------------

    The exemption would apply to all activities (including, e.g., 
training activities) at organizations whose primary function is the 
performance of firefighting. In order to comply with the proposed 
updates to 29 CFR 1910.156, firefighting organizations would have 
programs in place that address heat-related hazards for their 
employees.
    For employers with employees who perform emergency response 
activities as members of workplace emergency response teams (i.e., 
groups of employees who prepare for and respond to emergency incidents 
at their workplace as a collateral duty to their regular daily work 
assignments; see 89 FR at 7803), or who perform emergency medical 
services or technical search and rescue, this exemption would only 
apply when employees are performing emergency response activities. This 
means during periods while these employees are performing other duties 
unrelated to emergency response, employers would be required to comply 
with the provisions of the standard, unless subject to another 
exemption. For example, employees who are part of a manufacturing 
plant's emergency response team would be exempt from the standard while 
responding to an incident, such as a medical emergency, but would be 
covered by the standard when performing their regular daily work 
assignments. All other employees not engaged in emergency response 
would also be covered by this proposed standard. Although OSHA is 
proposing to exempt fire departments entirely, the agency is not 
proposing to entirely exempt organizations that have employees who 
perform EMS or technical search and rescue. This is because many 
organizations who perform EMS (e.g., hospitals) or technical search and 
rescue also conduct many other activities unrelated to emergency 
response and OSHA intends these other activities to be covered by this 
proposed standard unless another exemption applies.
    The Emergency Response proposal includes several hazard assessment 
and risk management requirements that would encompass heat hazards 
faced by emergency responders (see 89 FR at 7813-7814). Further, in the 
NPRM for Emergency Response, OSHA noted this rulemaking on heat illness 
prevention and invited comment on whether the agency should include 
specific requirements related to heat for some non-emergency activities 
of emergency responders. At the same time, the agency recognized that 
at times emergency responders must perform their duties regardless of 
environmental conditions (89 FR at 7801). OSHA has preliminarily 
concluded that it is appropriate to address any heat-related hazards 
posed by emergency response activities in this separate rulemaking.
    This proposed standard would also not apply to employees when they 
are undertaking emergency response activities under 29 CFR 1910.120, 
1910.146, 1910.156, subpart P, 1926.65, and 1926.1211. Many of these 
standards provide employees protection from heat exposure during 
emergency activities. In addition, OSHA believes that the emergency 
nature of these activities warrant special consideration and the agency 
is therefore exempting them from this proposed standard. However, this 
proposed standard would otherwise apply to these employees during non-
emergency regular operations unless another exemption applies. For 
example, with regard to the Hazardous Waste Operations and Emergency 
Response Standard (HAZWOPER) (29 CFR 1910.120 and 1926.65), which 
covers employees who are exposed or potentially exposed to hazardous 
substances and engaged in one of the operations as specified by 29 CFR 
1910.120(a)(1)(i) through (v) and 1926.65(a)(1)(i) through (v), such as 
clean-up operations, employees would only be exempt when responding to 
emergency situations and would be covered by the standard when 
participating in general hazardous waste operations.
    Paragraph (a)(2)(iv) would exclude work activities performed in 
indoor work areas or vehicles where air-conditioning consistently keeps 
the ambient temperature below 80 [deg]F. OSHA specifies using ambient 
temperature, as most heating, ventilation, and air-conditioning (HVAC) 
systems automatically report ambient temperature. Properly functioning 
HVAC units also regulate indoor humidity levels, which would result in 
similar measures of ambient temperature and heat index.
    This exemption would only apply to indoor work areas and vehicles 
that are consistently below an ambient temperature of 80 [deg]F. The 
employer must ensure that the air-conditioning system consistently 
maintains an ambient temperature below 80 [deg]F during work activities 
for the exemption to apply. OSHA recognizes that there may be 
unexpected malfunctions of air-conditioning systems that result in 
periods of time without air-conditioning before a system is repaired. 
In these situations, OSHA would expect that the employer takes steps to 
expeditiously repair the air-conditioning system and return the 
workplace to an ambient temperature below 80 [deg]F.
    Paragraph (a)(2)(v) would exclude telework (i.e., work done from 
home or another remote location of the employee's choosing). OSHA 
generally does not hold employers liable for employees' home offices 
and conditions of the telework environment (see CPL 02-00-125, 
available at https://www.osha.gov/enforcement/directives/cpl-02-00-125). However, only the work activities employees perform while 
teleworking would be exempt and employers would be required to comply 
with the standard when employees are on site if other exemptions do not 
apply. For example, the standard would not cover work activities 
conducted at an employee's home on Tuesdays and Thursdays in a given 
week but would cover the employee's work activities at their employer's 
office on Mondays, Wednesdays, and Fridays (unless another exemption 
applies).
    Paragraph (a)(2)(vi) would exclude sedentary work activities at 
indoor work areas that only involve some combination of the following: 
sitting, occasional standing and walking for brief periods of time, and 
occasional lifting of objects weighing less than 10 pounds. The 
exemption is intended to apply to work sites such as offices where 
employees perform sedentary work activities for extended periods of 
time (e.g., all or most of the workday). This exemption only applies to 
indoor work activities, which are not generally subject to factors such 
as solar radiation, which are common in outdoor exposures. OSHA 
preliminarily concludes that employees engaged in

[[Page 70770]]

indoor sedentary work activities are at lower risk of heat-related 
injury and illness, as production of metabolic heat is not 
substantially elevated. Experimental studies of groups exposed to heat 
(111.4 [deg]F (44 [deg]C), 30% relative humidity) while resting in a 
seated position indicate core body temperature does not rise more than 
1 [deg]C (1.8 [deg]F) over multiple hours (Kenny et al., 2017; Notley 
et al., 2020). In addition to sitting, the exemption allows for indoor 
work activities to include occasional standing and walking for brief 
periods of time, and occasional lifting of objects weighing less than 
10 pounds. When using the term ``occasional'' OSHA means up to one-
third of the workday (BLS, 2021), however these activities could only 
be performed for brief periods of time over the course of the day for 
the exemption to apply. For example, work activities performed at a 
desk indoors, where the employee is seated and performing computer work 
for the majority of their shift, but with occasional standing, as well 
as walking short distances (e.g., to use the photocopier, to collect 
office mail), would be exempt from the standard.
    In addition, this exemption would apply to indoor operation of 
vehicles while seated. For example, operation of a forklift inside of a 
warehouse while seated would be considered an indoor sedentary work 
activity and would be exempt. However, if a forklift operator's duties 
involved loading and unloading heavy objects (greater than 10 pounds), 
they would not be exempt from the standard. Other examples of 
activities that would be exempt include indoor operation of reach 
trucks, tow trucks, pallet trucks, golf carts, and other vehicles where 
employees are seated.
    This exemption would apply where employees are engaged in sedentary 
work activities regardless of indoor temperature. While employees 
performing these activities are likely at lower risk of experiencing 
heat-related injury and illness, OSHA seeks comment as to whether the 
sedentary work activities exemption should be limited to work 
activities performed in indoor environments below a specified threshold 
temperature (e.g., the high heat trigger) or whether this exemption 
should account for certain workplace conditions. For example, should 
this exemption cover an employer with employees who meet the criteria 
in this proposed exemption, but whose work area is near a heat 
generating process and impacted by radiant heat?
    Paragraph (a)(3) specifies that employers whose employees all 
exclusively perform activities described in paragraphs (a)(2)(i) 
through (vi) are exempt from this standard. Employers may have 
employees who would be exempt from the standard (e.g., employees 
working indoors where air-conditioning consistently keeps the ambient 
temperature below 80 [deg]F), as well as employees who would be covered 
by the standard (e.g., employees harvesting produce outdoors). These 
employers would be required to comply with the provisions of the 
standard for the employees who perform work activities that are covered 
by the standard. However, some employers may only have employees that 
exclusively perform work activities that are exempt from the proposed 
standard. For example, an employer with employees who all either 
telework from home or other locations of their choosing or work inside 
a building with air-conditioning that consistently keeps the ambient 
temperature below 80 [deg]F would be exempt from the standard.
I. Requests for Comments
    OSHA requests comments and evidence regarding the following:
     Whether any of the proposed exclusions of emergency 
response activities already covered under the standards listed in 
proposed paragraph (a)(2)(iii) should be covered by this proposed 
standard. If so, provide evidence and describe reason for why these 
activities should not be excluded;
     Where an employer relies on the exemption in proposed 
paragraph (a)(2)(iv) to exclude work activities performed in indoor 
work areas or vehicles where air-conditioning consistently keeps the 
ambient temperature below 80 [deg]F, whether the standard should 
address situations where the air-conditioning system does not function 
properly and the ambient temperature reaches or exceeds 80 [deg]F; for 
example, should certain requirements of the standard apply in this 
scenario? Additionally, whether the standard should specify how long 
the air-conditioning system can be out of order before the exemption no 
longer applies;
     Whether the description of sedentary work in the proposed 
standard is appropriate, and if not, what revisions would be 
appropriate;
     Whether the standard should exempt all sedentary work 
activities indoors or limit the exemption to only activities performed 
below an upper limit (e.g., below the high heat trigger) at or above 
which the exemption would no longer apply, and if so, what the upper 
limit should be and what evidence exists demonstrating that even 
sedentary work performed indoors can be a hazard to workers at or above 
that limit; and
     Whether the exemption for sedentary work activities should 
be expanded to include work performed outdoors.

B. Paragraph (b) Definitions

    Paragraph (b) defines several terms used in the proposed standard. 
First, it defines Acclimatization to mean the body's adaptation to work 
in the heat as a person is exposed to heat gradually over time, which 
reduces the strain caused by heat stress and enables a person to work 
with less chance of heat illness or injury.
    Section V.C., Risk Reduction contains more information on 
effectiveness of acclimatization. This definition is included because 
paragraph (e)(7) of the proposed standard establishes requirements to 
protect new and returning employees who are not acclimatized. Proposed 
paragraph (e)(7) requires that employers implement one of two 
acclimatization protocols for new and returning employees when the 
initial heat trigger is met or exceeded. Under paragraph (j), employers 
must implement acclimatization protocols at no cost to the employee. In 
addition, proposed paragraph (h)(1)(iii) requires that employees be 
trained that lack of acclimatization is a risk factor for HRI.
    Ambient temperature means the temperature of the air surrounding a 
body. Other terms for ambient temperature include ``air temperature'' 
or ``dry bulb temperature.'' Ambient temperature is measured by a 
standard thermometer and often what people refer to when using the term 
``temperature.'' Ambient temperature is defined because it is used in 
the definitions for heat index and wet bulb globe temperature, in 
addition to proposed paragraphs (a) Scope and application, (d) 
Identifying heat hazards, (e) Requirements at or above the initial heat 
trigger, and (f) Requirements at or above the high heat trigger.
    Cooling personal protective equipment (PPE) means equipment that is 
worn to protect the user against heat-related injury or illness. This 
definition is included to clarify the requirement under proposed 
paragraph (e)(1) that if the employer provides employees with cooling 
PPE, the cooling properties must be maintained during use.
    Cooling PPE is gear designed to help maintain a safe body 
temperature for individuals working in hot environments or engaged in 
physically demanding activities. Cooling PPE typically employs various 
technologies to facilitate heat dissipation and

[[Page 70771]]

enhance comfort, such as water absorption crystals or phase change 
materials (PCM) which draw heat away from the wearer. Cooling bandanas 
and neck wraps are worn around the neck and can be soaked in cold 
water. Additionally, other types of clothing may incorporate materials 
that have cooling properties.
    Heat index means the National Weather Service heat index, which 
combines ambient temperature and humidity. It provides a number that 
can be used to indicate how hot it feels. There are several tools for 
measuring heat index in both indoor and outdoor work areas. For outdoor 
work areas, the OSHA-NIOSH Heat Safety Tool app and other phone-based 
weather apps can be used to show the heat index by location as well as 
hourly forecasts. For indoor work areas, employers can enter 
measurements of humidity and ambient temperature into the NOAA Heat 
Index Calculator. There are also monitoring devices that report heat 
index. Heat index is defined because the term is used in definitions of 
high heat trigger and initial heat trigger. The term is also used in 
proposed paragraphs (c) Heat injury and illness prevention plan, (d) 
Identifying heat hazards, and (e) Requirements at or above the initial 
heat trigger.
    High heat trigger means a heat index of 90 [deg]F or a wet bulb 
globe temperature (WBGT) equal to the NIOSH Recommended Exposure Limit. 
See explanations for the definitions of wet bulb globe temperature 
(WBGT) and Recommended Exposure Limit (REL) for more information about 
those terms. OSHA is including a definition for high heat trigger 
because exposures at or above the high heat trigger would require the 
implementation of a number of controls, in addition to the controls 
that would be implemented under the initial heat trigger in proposed 
paragraph (e). The controls implemented under the initial heat trigger 
are described below under the definition for Initial Heat Trigger. The 
additional controls that would be implemented under the high heat 
trigger under proposed paragraph (f) include required rest breaks, 
observation for signs and symptoms, hazard alerts, and warning signs 
for excessively high heat areas. See Section VII.F., Explanation of 
Proposed Requirements for more information on these controls. The 
scientific basis supporting the establishment of the high heat trigger 
at a heat index of 90 [deg]F or a WBGT equal to the NIOSH REL is 
explained in in Section V.B., Basis for Initial and High Heat Triggers.
    Indoor/indoors means an area under a ceiling or overhead covering 
that restricts airflow and has along its entire perimeter walls, doors, 
windows, dividers, or other physical barriers that restrict airflow, 
whether open or closed. Possible examples for indoors include work in a 
garage, even if the garage door is open; the interior of a warehouse, 
even if multiple doors are open on loading docks; and a shed with four 
walls and a ceiling, even if the windows are open. Construction 
activity is considered to be work in an indoor environment when 
performed inside a structure after the outside walls and roof are 
erected. This definition is included because the term is used in 
definitions for outdoor/outdoors, and proposed paragraphs (a) Scope and 
application, (d) Identifying heat hazards, (e) Requirements at or above 
the initial heat trigger, (f) Requirements at or above the high heat 
trigger, and (i) Recordkeeping.
    Initial heat trigger means a heat index of 80 [deg]F or a WBGT 
equal to the NIOSH Recommended Alert Limit (RAL). See explanations for 
the definitions of wet bulb globe temperature (WBGT) and Recommended 
Alert Limit (RAL) for more information about those terms. OSHA is 
including a definition for initial heat trigger because exposures at or 
above the initial heat trigger would require the implementation of a 
number of controls under proposed paragraph (e), including requirements 
for drinking water, break area(s) for indoor and outdoor work sites, 
indoor work area controls, acclimatization of new and returning 
employees, rest breaks if needed to prevent overheating, effective 
communication, and maintenance of PPE cooling properties if PPE is 
provided. See Section VII.E., Explanation of Proposed Requirements for 
more information on these controls. The scientific basis supporting the 
establishment of the initial heat trigger at a heat index of 80 [deg]F 
or a wet bulb globe temperature (WBGT) equal to the NIOSH RAL is 
explained in detail in Section V.B., Basis for Initial and High Heat 
Triggers.
    Outdoor/outdoors means an area that is not indoors, as defined 
above. The definition also specifies that vehicles operated outdoors 
are considered outdoor work areas for purposes of this standard unless 
exempted by paragraph (a)(2). Examples of outdoor work include tasks 
performed in agricultural fields and under canopies and pavilions. This 
term is defined because it is used in proposed paragraphs (d) 
Identifying heat hazards, (e) Requirements at or above the initial heat 
trigger, and (h) Training.
    Radiant heat means heat transferred by electromagnetic waves 
between surfaces. This definition further notes that sources of radiant 
heat include the sun, hot objects, hot liquids, hot surfaces, and fire.
    Radiant heat is transferred from a hotter object to a cooler 
object. The transfer of radiant heat can occur across distances and 
does not require objects to touch each other. Infrared radiation is a 
common source of radiant heat that is encountered in foundries, and in 
iron, steel, and glass industries (NIOSH, 2016). Sources of exposure to 
radiant heat in the workplace can include furnaces, ovens, and 
combustion. Radiant heat is defined because it is included in the 
definition for wet bulb globe temperature (WBGT) and is used in 
paragraph (e) Requirements at or above the initial heat trigger.
    Recommended Alert Limit (RAL) means the NIOSH-recommended heat 
stress alert limits for unacclimatized workers. OSHA is proposing to 
incorporate by reference NIOSH Publication No. 2016-106 Criteria for a 
Recommended Standard: Occupational Exposure to Heat and Hot 
Environments (NIOSH, 2016). OSHA is including a definition for RAL 
because the initial heat trigger incorporates the NIOSH RAL. Thus, 
several provisions of the standard are triggered by either a heat index 
of 80 [deg]F or a wet bulb globe temperature (WBGT) equal to the NIOSH 
RAL. See Explanation of Proposed Requirements for Definitions (initial 
heat trigger, wet bulb globe temperature) and proposed paragraph (e), 
Requirements at or above the Initial heat trigger for more details.
    NIOSH (2016) developed the RAL to protect most healthy non-
acclimatized employees from adverse effects of heat stress and 
recommends that total heat exposure for non-acclimatized employees be 
controlled to maintain combinations of environmental and metabolic heat 
below the applicable RAL in order to maintain thermal equilibrium. 
Environmental exposures are based on WBGT, which accounts for the 
contributions of ambient temperature, radiant heat, humidity, and wind 
speed. Metabolic heat production is estimated by workload. The RAL 
assumes employees are wearing ``the conventional one-layer work 
clothing ensemble,'' but NIOSH provides guidance for adjusting the WBGT 
based on the types of clothing or PPE worn. The formula for calculating 
the RAL is: RAL [ [deg]C-WBGT] = 59.9-14.1 log10M[W], where 
M is metabolic rate in watts (W).
    Recommended Exposure Limit (REL) means the NIOSH-recommended heat

[[Page 70772]]

stress exposure limits for acclimatized workers. OSHA is proposing to 
incorporate by reference NIOSH Publication No. 2016-106 Criteria for a 
Recommended Standard: Occupational Exposure to Heat and Hot 
Environments (NIOSH, 2016). OSHA is including a definition for REL 
because the high heat trigger incorporates the NIOSH REL. Thus, several 
provisions of the standard are triggered by either a heat index of 90 
[deg]F or a wet bulb globe temperature (WBGT) equal to the NIOSH REL. 
See Explanation of Proposed Requirements for Definitions (high heat 
trigger, wet bulb globe temperature) and proposed paragraph (f), 
Requirements at or above the high heat trigger for more details.
    NIOSH (2016) developed the REL to protect most healthy acclimatized 
employees from adverse effects of heat stress and recommends that total 
heat exposure for acclimatized employees be controlled to maintain 
combinations of environmental and metabolic heat below the applicable 
REL in order to maintain thermal equilibrium. Environmental exposures 
are based on WBGT, which accounts for the contributions of ambient 
temperature, radiant heat, humidity, and wind speed. Metabolic heat 
production is estimated by workload. The REL assume employees are 
wearing ``the conventional one-layer work clothing ensemble,'' but 
NIOSH provides guidance for adjusting WBGT based on the types of 
clothing or PPE worn. The formula for calculating the REL is: REL [ 
[deg]C-WBGT]= 56.7-11.5 log10M[W], where M is metabolic rate 
in watts (W).
    Shade is defined as the blockage of direct sunlight, such that 
objects do not cast a shadow in the area of blocked sunlight. This 
definition is included to clarify the requirements for use of shade as 
a control in outdoor break areas under proposed paragraph (e)(3)(i). 
Shade can be artificial or naturally occurring. See Explanation of 
Proposed Requirements for paragraph (e)(3).
    Signs and symptoms of heat-related illness means the physiological 
manifestations of a heat-related illness and includes headache, nausea, 
weakness, dizziness, elevated body temperature, muscle cramps, and 
muscle pain or spasms. This term is used throughout the proposal to 
refer to a range of signs and symptoms that may result from a variety 
of heat-related illnesses (see Section IV., Health Effects for a 
detailed discussion of heat-related illnesses and the accompanying 
symptoms). This term is defined to provide clarity about scenarios for 
which an employer must develop procedures for responding to employees 
experiencing signs and symptoms of heat-related illness in their heat 
emergency response plan, as well as the scenarios that an employer 
would be required to take specific actions to aid affected employees 
under proposed paragraph (g). This definition also provides clarity on 
the requirements to train employees on signs and symptoms of heat-
related illness (see proposed paragraph (h)(iv)) and monitor employees 
for signs and symptoms of heat-related illness (see proposed paragraph 
(f)(3).
    Signs and symptoms of a heat emergency means the physiological 
manifestations of a heat-related illness that require emergency 
response and include loss of consciousness (i.e., fainting, collapse) 
with excessive body temperature, which may or may not be accompanied by 
vertigo, nausea, headache, cerebral dysfunction, or bizarre behavior. 
This could also include staggering, vomiting, acting irrationally or 
disoriented, having convulsions, and (even after resting) having an 
elevated heart rate. This term is defined to provide clarity about 
scenarios for which an employer must develop procedures to respond to 
employees experiencing signs and symptoms of a heat emergency in their 
heat emergency response plan, as well as the scenarios in which an 
employer would be required to take specific actions to aid affected 
employees under proposed paragraph (g). This definition also provides 
clarity on the requirements to train employees on signs and symptoms of 
heat-related illness and which ones require immediate emergency action 
(see proposed paragraph (h)(iv)).
    Vapor-impermeable clothing means full-body clothing that 
significantly inhibits or completely prevents sweat produced by the 
body from evaporating into the outside air. The definition further 
indicates that examples include encapsulating suits, various forms of 
chemical resistant suits, and other forms of non-breathable PPE. This 
definition is included because under proposed paragraph (c)(3) 
employers that have employees who wear vapor-impermeable clothing would 
be required to evaluate heat stress hazards resulting from these 
clothing and implement policies and procedures based on reputable 
sources to protect employees while wearing this clothing. Vapor-
impermeable clothing is also referred to as ``vapor barrier'' clothing. 
It is a type of protective clothing that employers may provide to 
employees to protect them from chemical, physical, or biological 
hazards for work tasks such as hazardous waste clean-up. Examples 
include metallic reflective clothing or chemical resistant clothing 
made from plastics such as vinyl or nylon-reinforced polyethylene 
(Mihal, 1981). Materials made from 100% high density polyethylene 
(e.g., Tyvek[supreg]) that allow water vapor and gases to pass through 
are not vapor-impermeable, but lamination of the materials with some 
substances such as polyvinyl chloride (PVC) can change the 
breathability of the materials and render them vapor-impermeable 
(DuPont, 2024; Paull and Rosenthal, 1987). Because the proposed 
definition indicates ``full-body clothing'', it would not include 
vapor-impermeable PPE that covers small areas of the body (e.g., 
gloves, boots, aprons, leggings, gauntlets). However, clothing such as 
boots and gloves made from vapor-impermeable materials such as rubber 
may be part of whole-body, vapor-impermeable clothing ensembles (Mihal, 
1981; Paull and Rosenthal, 1987). Employers could check product 
information provided by manufacturers to determine if clothing worn by 
their employees qualifies as vapor-impermeable clothing.
    Vehicle means a car, truck, van, or other motorized means of 
transporting people or goods. Other examples may include a forklift, 
reach truck, tow truck, pallet truck, or bus, among others. In 
addition, vehicles may also include equipment such as a bulldozer, road 
grader, farm tractor, or crane. Under the proposed definitions, a 
vehicle would be a work area when a worker's work activities occur in 
the vehicle.
    Wet Bulb Globe Temperature (WBGT) is a heat metric that takes into 
account ambient temperature, humidity, radiant heat from sunlight or 
artificial heat sources, and air movement. It can be measured in both 
indoor and outdoor work areas, however there are separate formulas 
depending on whether the device is being used indoors or outdoors. WBGT 
is used by NIOSH and ACGIH in their guidance for evaluating 
occupational heat stress. The term is defined because it is used in the 
definitions for the high and initial heat triggers and in proposed 
paragraphs (c) Heat injury and illness prevention plan and (d) 
Identifying heat hazards.
    Work area means an area where one or more employees are working 
within a work site. This includes any area where an employee performs 
any work-related activity. A work area may be located at the employer's 
premises or other locations where an employee may be engaged in work-
related activities or is present as a condition of their employment. 
Work area is defined because it is referenced in several provisions of 
the proposed standard, including (a) Scope and application, (c)

[[Page 70773]]

Heat injury and illness prevention plan (HIIPP), (d) Identifying heat 
hazards, (e) Requirements at or above the initial heat trigger, (f) 
Requirements at or above the high heat trigger, and (i) Recordkeeping.
    Work site means a physical location (e.g., fixed, mobile) where the 
employer's work or operations are performed. It includes outdoor and 
indoor areas, individual structures or groups of structures, and all 
areas where work or any work-related activity occurs (e.g., taking 
breaks, going to the restroom, eating, entering or exiting work). The 
work site includes the entirety of any space associated with the 
employer's operations (e.g., workstations, hallways, stairwells, 
breakrooms, bathrooms, elevators) and any other space that an employee 
might occupy in arriving, working, or leaving. A work site may or may 
not be under the employer's control. Work site is defined because it is 
referenced in several provisions of the proposed standard including 
Heat Injury and Prevention Plan (HIIPP) (proposed paragraph (c)), 
Identifying heat hazards (proposed paragraph (d)), Requirements at or 
above the initial heat trigger (proposed paragraph (e)), Requirements 
at or above the high heat trigger (proposed paragraph (f)), Heat 
illness and emergency response and planning (proposed paragraph (g)), 
and Training (proposed paragraph (h)).
I. Requests for Comments
    OSHA requests comments as to whether the proposed definitions are 
appropriate, and whether any additional terms should be defined in the 
standard.

C. Paragraph (c) Heat Injury and Illness Prevention Plan

    Proposed paragraph (c) includes provisions for the development and 
implementation of a work site heat injury and illness prevention plan, 
referred to as a ``HIIPP'' or ``plan'' for the remainder of this 
section, as well as requirements regarding what would need to be in the 
plan. The development of a HIIPP, including comprehensive policies and 
procedures, is necessary to ensure that all affected employees, 
including exposed workers, supervisors, and heat safety coordinators, 
understand where heat hazards exist at the workplace and the workplace-
specific measures that must be utilized to address those hazards. The 
NIOSH Criteria Document provides information on the importance of a 
HIIPP to reduce the risk of heat-related injuries and illness (NIOSH, 
2016). Requiring a HIIPP is also consistent with regulations from 
several of the States that have enacted or proposed heat-specific 
standards. There is a plan requirement in existing heat standards from 
California (Cal. Code of Regs. tit. 8, section 3395 (2005)), Washington 
(Wash. Admin. Code sections 296-62-095 through 296-62-09560; 296-307-
097 through 296-307-09760 (2023)); and Oregon (Or. Admin. R. 437-002-
0156 (2022); Or. Admin. R. 437-004-1131 (2022)). Maryland and Nevada 
proposed heat standards that would also require a HIIPP (MD, 2024; NV, 
2022). Additionally, this requirement aligns with the recommendations 
from the NACOSH Heat Injury and Illness Prevention Work Group, where 
the group provided a list of potential elements to include in a HIIPP. 
All the requirements in paragraph (c) would have to be included in the 
employer's HIIPP.
    Paragraph (c)(1) would require employers to develop and implement a 
comprehensive HIIPP for each work site. Under proposed paragraph (b), a 
work site is defined as a physical location (e.g., fixed, mobile) where 
the employer's work or operations are performed. If an employer has 
multiple work sites that are substantially similar, the HIIPP may be 
developed by work site type rather than by individual work sites so 
long as any site-specific information is included in the plan (e.g., 
phone numbers and addresses or site-specific heat sources). For 
example, if an employer has developed a corporate HIIPP that includes 
information about job tasks or exposure scenarios that apply at 
multiple work sites, this information can be used in the development of 
HIIPPs for individual work sites. When employees are in work areas not 
controlled by the employer (like private residences), employers would 
need procedures for how they will ensure compliance with the standard 
(e.g., ensure that effective communication is being maintained 
(proposed paragraph (f)(3)(iii)) and employees are receiving hazard 
alerts to remind them of protections such as the importance of drinking 
plenty of water, their right to take breaks, and locations of break 
sites and drinking water (proposed paragraph (f)(4)). These employers 
must include such policies and procedures in their HIIPP to protect 
their employees entering those locations not controlled by the 
employer.
    Proposed paragraph (c)(2) specifies the contents of the HIIPP. 
Proposed paragraph (c)(2)(i) would require the HIIPP to include a 
comprehensive list of the types of work activities covered by the plan. 
For example, a landscaping company could indicate that all employees 
conducting outdoor work at or above the initial heat trigger for at 
least 15 minutes in any 60-minute period (e.g., lawn care workers, 
gardeners, stonemasons, and general laborers) would be covered by the 
HIIPP. (See proposed paragraphs (a)(2)(i), (ii), and (iv) and 
Explanation for Proposed Requirements for Paragraph (a) Scope and 
Application for more detail about coverage under the standard.) 
Paragraph (c)(2)(ii) would require the inclusion of the policies and 
procedures that are necessary to comply with the requirements of this 
proposed standard. See Explanation of Proposed Requirements for 
paragraphs (d) through (j) for examples of how employers could comply 
with the proposed provisions. OSHA understands that a HIIPP must be 
adaptable to the physical characteristics of the work site and the job 
tasks performed by employees, as well as the hazards identified by the 
employer when designing their HIIPP. Employers could also include other 
policies, procedures, or information necessary to comply with any 
applicable Federal, State, or local laws, standards, and guidelines in 
their HIIPPs. Paragraph (c)(2)(iii) would require that employers 
identify the heat metric (i.e., heat index or wet bulb globe 
temperature) that the employer will monitor to comply with paragraph 
(d). For more information on heat metrics, see Explanation for Proposed 
Requirements for Paragraph (b) Definitions for heat index and WBGT.
    Paragraph (c)(3) would require that, in cases where employees wear 
vapor-impermeable clothing (also called vapor barrier clothing), 
employers must evaluate heat stress hazards resulting from this 
clothing and implement policies and procedures based on reputable 
sources to protect employees while wearing these clothing. The employer 
must include these policies and procedures and document the evaluation 
in the HIIPP. Under proposed paragraph (b), vapor-impermeable clothing 
is defined as full-body clothing that significantly inhibits or 
completely prevents sweat produced by the body from evaporating into 
the outside air. The definition further indicates that examples include 
encapsulating suits, various forms of chemical resistant suits, and 
other forms of non-breathable PPE. For more information on vapor-
impermeable clothing, see the Explanation for Proposed Requirements for 
paragraph (b) Definitions. This attention to vapor-impermeable clothing 
is essential given that significant or complete inhibition of sweat 
evaporation can greatly increase the potential for heat stress and

[[Page 70774]]

resulting heat strain and HRI (Mihal, 1981).
    The requirement that employers evaluate heat stress and develop 
policies and procedures to protect employees based on reputable sources 
allows for flexibility, given that there is variability in duration of 
use of the vapor-impermeable clothing and that workload also varies 
across job tasks and occupations. Examples of reputable sources 
employers can consult to assess heat stress and develop policies and 
procedures to protect employees wearing vapor-impermeable clothing 
include recommendations by NIOSH (2016) and ACGIH (2023). An example of 
a policy employers might adopt to protect employees wearing vapor-
impermeable clothing is implementing the protections in the standard at 
a lower temperature threshold. Such an approach has been used in State 
standards such as the Washington heat standard for outdoor workplaces 
(Wash. Admin. Code 296-307-09747 (2023)). In Washington State's heat 
standard, employers must implement certain controls when employees are 
wearing vapor barrier clothing, and the temperature is above 52 [deg]F. 
Paragraph (c)(3) does not apply to vapor-permeable clothing or PPE such 
as cotton coveralls, SMS polypropylene or polyolefin coveralls, double 
layer woven clothing, or wool shirts (ACGIH, 2023; ACGIH, 2017; NIOSH, 
2016).
    Paragraph (c)(3) would require the employer to document in the 
HIIPP the hazard evaluation performed to comply with this provision and 
to include in the HIIPP the policies and procedures developed to 
protect employee's wearing vapor-impermeable clothing. Although OSHA is 
not specifying a particular form for the required hazard evaluation, an 
effective hazard evaluation would include a review of environmental 
heat exposures, a review of the high-risk area(s), tasks, and 
occupations, and an evaluation of the length of time and intensity of 
task when wearing vapor-impermeable clothing. Policies and procedures 
should include communication of the status of planned or completed 
actions to employees who may have to wear vapor-impermeable clothing to 
complete work tasks. For more information on identifying heat hazards, 
see Explanation of Proposed Requirements for paragraph (d) below.
    Under proposed paragraph (c)(4), an employer with more than 10 
employees would be required to develop and implement a written HIIPP. 
While OSHA has concluded that a HIIPP is necessary for all employers 
covered by the standard, OSHA has determined that only employers with 
more than 10 employees need to have a written plan. This cutoff of 10 
employees is consistent with OSHA's practice of allowing employers with 
10 or fewer employees to communicate their emergency action plans (29 
CFR 1910.38) and fire prevention plans (29 CFR 1910.39) orally to 
employees. OSHA expects that small employers with 10 or fewer employees 
are likely to have less complicated HIIPPs and will communicate with 
employees verbally. The agency does not believe that there is a high 
likelihood of misunderstanding when employers communicate their HIIPPs 
to employees verbally. As a result, OSHA does not believe the added 
burden on small employers of establishing a written plan is necessary. 
However, small employers may opt to create a written HIIPP if they find 
doing so is helpful in developing and implementing their plans.
    In contrast, the agency is concerned that when employers have more 
than 10 employees, there is likely sufficient complexity in the 
employer's operation that putting the HIIPP in writing is necessary to 
establish clear expectations and prevent miscommunication. For example, 
employers with more than 10 employees may have employees working in 
multiple locations or on multiple shifts, increasing the likelihood 
that verbally communicating the employer's HIIPP will be ineffective. 
Therefore, OSHA preliminarily finds that having a written HIIPP that 
employees of larger employers can easily access is essential to ensure 
those employees are informed about policies, programs, and protections 
implemented by their employers to protect them from hazardous heat 
exposure.
    An employer may have already developed and implemented a HIIPP. 
Existing plans may fulfill some of the requirements in this section. It 
is not OSHA's intent for employers to duplicate current effective 
HIIPPs, but each employer with a current HIIPP would have to evaluate 
that plan for completeness to ensure it satisfies all the requirements 
of this section. Employers with existing plans would be required to 
modify and/or update their current HIIPP plans to incorporate any 
missing required elements and provide training on these new updates or 
modifications to all employees (see the Explanation of Proposed 
Requirements for Paragraph (h) Training). Employers with more than 10 
employees would have to ensure their existing HIIPP is in writing.
    Paragraph (c)(5) would require the employer to designate one or 
more workplace heat safety coordinators to implement and monitor the 
HIIPP. Any employee(s) capable of performing the role who receives the 
training required by proposed paragraphs (h)(1) and (2) can be 
designated heat safety coordinator(s). This employee(s) does not need 
to be someone with specialized training. The heat safety coordinator(s) 
could be a supervisor or an employee that the employer designates. The 
heat safety coordinator(s) must have the authority to ensure compliance 
with all aspects of the HIIPP. This requirement would ensure heat 
safety coordinators can take prompt corrective measures when hazards 
are identified. Proposed paragraph (c)(5) would also require that for 
employers with more than 10 employees, the identity of the heat safety 
coordinator(s) must be documented in the written HIIPP. Employers must 
designate a heat safety coordinator(s) to implement and monitor the 
HIIPP plan, but the exact responsibilities of a heat safety 
coordinator(s) may vary based on the employer and work site. Some 
possible duties of the heat safety coordinator(s) could include 
conducting regular inspections of the work site to ensure the HIIPP is 
being implemented appropriately and to monitor the ongoing 
effectiveness of the plan. During such inspections, the heat safety 
coordinator(s) could observe employees to ensure they are protecting 
themselves by frequently drinking water or taking rest breaks that 
employers would be required to provide.
    Under proposed paragraph (c)(6), the employer would be required to 
seek the input and involvement of non-managerial employees and their 
representatives, if any, in the development and implementation of the 
HIIPP. An employer could seek feedback from employees through a variety 
of means, including safety meetings, a safety committee, conversations 
between a supervisor and non-managerial employees, a process negotiated 
with the exclusive bargaining agent (if any), or any other similarly 
interactive process. The method of soliciting employee input is 
flexible and may vary based on the employer and the work site. For 
example, a large employer with many employees may find a safety 
committee with representatives from various job categories combined 
with anonymous suggestion boxes to be more effective than individual 
conversations between supervisors and non-managerial employees. In the 
case of a unionized workplace, a safety committee established through a 
collective bargaining agreement may be the appropriate source for this 
input,

[[Page 70775]]

based on the definition and scope of the committee's work. In contrast, 
a small employer might determine that an ongoing interactive process 
between the employer and employees (e.g., regular safety meetings) is a 
more effective means of soliciting employee feedback. OSHA understands 
employees often know the most about potential hazards associated with 
their jobs. As such, employee participation is a key component of 
effective safety and health programs.
    Paragraph (c)(7) would require the employer to review and evaluate 
the effectiveness of the HIIPP whenever a heat-related injury or 
illness occurs that results in death, days away from work, medical 
treatment beyond first aid, or loss of consciousness, but at least 
annually. Following each review, the employer would be required to 
update the HIIPP as necessary. The employer would have to seek input 
and involvement of non-managerial employees and their representatives, 
if any, during any reviews and updates. OSHA preliminarily finds that a 
heat-related illness or injury that results in death, days away from 
work, medical treatment beyond first aid, or loss of consciousness 
warrants an evaluation of the HIIPP because it could potentially 
indicate a deficiency of the HIIPP. Additionally, the heat safety 
coordinator might learn of a deficiency during an inspection or from 
another employee. OSHA expects that employers would immediately address 
any identified deficiencies and update the HIIPP accordingly. Under 
proposed paragraph (h)(4)(iv), all employees would have to be retrained 
following a heat-related injury or illness that results in death, days 
away from work, medical treatment beyond first aid, or loss of 
consciousness, and under proposed paragraph (h)(4)(ii) employees would 
have to be retrained if identification of a deficiency results in an 
update to the HIIPP. OSHA preliminarily finds that effective heat 
injury and illness prevention plans would require periodic evaluation 
to ensure they are implemented as intended and continue to achieve the 
goal of preventing heat injury and illness and promoting workplace 
safety and health. This re-evaluation can result in improvements in 
controls to help reduce hazards.
    Paragraph (c)(8) would require the employer to make the HIIPP 
readily available at the work site to all employees performing work at 
the work site. The HIIPP would have to be readily accessible during 
each work shift to employees when they are in their work area(s). Paper 
copies, electronic access (i.e., accessible via smart phone) and other 
alternatives to maintaining paper copies of the HIIPP are permitted as 
long as no barriers to immediate employee access in each work site are 
created by such options.
    Paragraph (c)(9) would require the employer to ensure the HIIPP is 
available in a language each employee, supervisor, and heat safety 
coordinator understands. Under proposed paragraph (c)(4), this would 
require written translations of the plan in all languages that 
employees, supervisors, and heat safety coordinators understand. 
Employers could comply with this requirement by utilizing one of the 
numerous translator programs available online if the employer has a way 
to ensure accuracy of the translated materials. In cases where an 
employee, supervisor, or heat safety coordinator can read and 
comprehend English, but prefers to read in another language, the 
employer would have no obligation to provide a written translation of 
the plan in that individual's preferred language. If one or more 
employees are not literate, the employer would have to ensure that 
someone is available to read the written plan in a language that each 
employee understands. Likewise, for employers who have less than 10 
employees, the employer would have to ensure that someone is available 
to explain the plan in a language that each employee, supervisor, and 
heat safety coordinator understands. OSHA expects that an individual 
who speaks employees' languages will be available in all workplaces 
since effective communication between individuals such as employers, 
supervisors, and employees would need to occur in order for employees 
to understand the details about the work tasks they need to complete.
I. Requests for Comments
    OSHA requests comments and evidence regarding the following:
     The approaches that stakeholders are taking to assess heat 
stress and prevent HRI in employees wearing vapor-impermeable clothing;
     Whether OSHA should specify a temperature that would 
trigger all or certain requirements of the standard for employees 
wearing vapor-impermeable clothing;
     Additional approaches that OSHA should consider to protect 
employees wearing vapor-impermeable clothing;
     Whether the proposed requirement to seek input and 
involvement from non-managerial employees and their representatives 
under paragraph (c)(6) is adequate, or whether the explanation should 
be expanded or otherwise amended (and if so, how and why);
     Whether OSHA should define ``employee representative'' 
and, if so, whether the agency should specify that non-union employees 
can designate a non-employee third-party (e.g., a safety and health 
specialist, a worker advocacy group, or a community organization) to 
provide expertise and input on their behalf;
     Whether it is reasonable to require the HIIPP be made 
available in a language that each employee, supervisor, and heat and 
safety coordinator understands;
     What methods and programs are available to provide 
employees documents and information in multiple languages, whether 
there are languages for which these resources are not available, and 
how employers can provide adequate quality control to ensure that the 
translations are done properly; and
     Whether individuals are available at workplaces to provide 
verbal translations of the plan for employees who are not literate or 
do not speak English.

D. Paragraph (d) Identifying Heat Hazards

    Proposed paragraph (d) sets forth requirements for assessing where 
and when employees are exposed to heat at or above the initial and high 
heat triggers. It would require employers with outdoor work sites to 
monitor heat conditions at outdoor work areas by tracking local heat 
index forecasts or measuring the heat metric of their choosing (heat 
index or wet bulb globe temperature (WBGT)). It would require employers 
with indoor work sites to identify work areas where there is a 
reasonable expectation that employees are or may be exposed to heat at 
or above the initial heat trigger and implement a plan for monitoring 
these areas to determine when exposures above the initial and high heat 
triggers occur, using the heat metric of their choosing (heat index or 
WBGT). Determining when employees are exposed to heat at or above the 
initial and high heat triggers is critical for ensuring that employees 
are provided with appropriate protections (outlined in paragraphs (e) 
and (f)).
    Proposed paragraph (d)(1) would require employers whose employees 
perform work outdoors to monitor the heat conditions at the work areas 
where employees are working. Employers would have two options for 
complying with this requirement--tracking local heat index forecasts 
provided by National Weather Service (NWS) or other reputable sources 
or making on-

[[Page 70776]]

site measurements using monitoring device(s).
    Employers who choose to track local forecasts would need to consult 
a reputable source for local heat index forecasts such as their local 
NWS Weather Forecast Office, the OSHA-NIOSH Heat Safety Tool cell phone 
application, or another weather forecast website or cell phone 
application. When using these sources, employers would need to 
accurately enter the location of the work area. The OSHA-NIOSH Heat 
Safety Tool (and other cell phone applications) will automatically use 
GPS to determine the user's location, so the forecast may be inaccurate 
if using the tool at home and employers will need to manually enter the 
work area location in these situations.
    Employers who choose to conduct on-site monitoring would need to 
set up monitoring devices at or as close as possible to the work area. 
This could mean setting up the device(s) on a tripod a few yards away 
from an employee. When there are multiple work areas at the same work 
site, the employer could use a single monitoring device to measure heat 
exposure for multiple work areas if there is no reasonable anticipation 
that the heat exposure will differ between work areas. For example, if 
employees are harvesting crops on different fields but are within a 
mile of one another under similar work conditions, the employer could 
use a single monitoring device. If there is reasonable anticipation 
that employees at a work site have different levels of exposure, 
employers could measure the exposure at the work area of the 
employee(s) reasonably expected to have the highest exposure and apply 
that value to all employees at the work site instead of measuring the 
exposure for each work area.
    Employers using heat index as their heat metric could either use 
heat index monitors or measure temperature and humidity with separate 
devices. In the latter situation, these employers would need to use a 
heat index calculator, such as the one provided on the NWS website 
(NWS, 2023), to calculate heat index from the separate temperature and 
humidity readings. Employers using WBGT as their heat metric would need 
to take into account differences in solar radiation and wind between 
work areas when deciding whether a single measurement could be used for 
multiple work areas. For example, measurements of WBGT in a work area 
in the shade should not be applied to another work area that is not in 
the shade. Regardless of which metric they choose to use, employers 
conducting on-site monitoring should consult user manuals and ensure 
devices are calibrated and in working order. Employers should follow 
the device manufacturer's manual when conducting monitoring.
    Proposed paragraph (d)(2) would require employers whose employees 
perform work outdoors to consult the weather forecast or their 
monitoring device(s)--whichever they are using to comply with paragraph 
(d)(1)--frequently enough to determine with reasonable accuracy when 
conditions at the work area reach the initial and high heat triggers. 
Employers consulting forecasts would need to check the forecast as 
close to the start of the work shift as possible to determine whether 
and when the heat index at the work area may be at or above the initial 
or high heat triggers. Depending on the forecast or conditions at the 
work site, the employer then may or may not need to conduct further 
monitoring during the day. If, for example, the employer consulted the 
OSHA-NIOSH Heat Safety Tool before the work shift and it indicated that 
the heat index would exceed the initial heat trigger but not the high 
heat trigger during the last four hours of the work shift, the employer 
would need to either: (1) implement control measures in accordance with 
paragraph (e) for those four hours, or (2) consult the Heat Safety Tool 
again later in the day and implement control measures in accordance 
with paragraph (e) only for the hours during which real-time conditions 
reported by the application exceed the initial heat trigger (which may 
be more or less than four hours if the forecast earlier in the day 
underestimated or overestimated the heat index). However, if the 
employer consulted the OSHA-NIOSH Heat Safety Tool before the work 
shift and it indicated that the heat index would be close to the 
initial heat trigger but not exceed it, employers would need to check 
the forecast again later in the day to determine whether the trigger 
was exceeded. Employers would need to use short-term forecasts (i.e., 
hourly) rather than long-term forecasts (e.g., weekly, monthly) to 
comply with proposed paragraphs (d)(1) and (2). Ultimately, the 
employer is responsible for ensuring that the controls required at the 
initial and high heat trigger are in place when those triggers are met, 
and they should make decisions regarding the frequency of monitoring 
with this in mind.
    Likewise, employers who conduct on-site monitoring in order to 
comply with paragraph (d)(1) will need to develop a reasonable 
measurement strategy that is adapted to the expected conditions. If 
forecasts provide no suggestion that the initial heat trigger could be 
reached during the work shift, an employer may not need to take any 
measurements. Where temperatures are expected to approach the initial 
or high heat triggers, several measurements may be necessary, 
particularly as the hottest part of the day approaches. For example, if 
the employer measures at 10 a.m. and the heat index is very close but 
below the initial heat trigger, the employer would likely need to 
either check again sometime shortly thereafter or assume that the 
trigger is exceeded. WBGT accounts for additional parameters--air speed 
and radiant heat--so employers using WBGT may need to make additional 
measurements when these conditions change at the work site.
    Proposed paragraphs (d)(3)(i) and (ii) outline the requirements for 
assessing heat hazards in indoor work sites, which differ slightly from 
the requirements for outdoor work sites, in that employers would need 
to identify the work areas where they reasonably expect employees to be 
exposed to heat at or above the initial heat trigger and then create a 
monitoring plan to determine when employees in those work areas are 
exposed to heat at or above the initial and high heat triggers.
    Employers could determine which work areas are expected to have 
employee exposure at or above the initial heat trigger by consulting 
various data sources, such as previously collected monitoring data, 
site or process surveys, employee interviews and input, and heat injury 
and illness surveillance data. Work areas near heat-generating 
machinery are one example of where there may be a reasonable 
expectation of employee exposure at or above the initial heat trigger. 
In addition to heat-generating equipment, employers must determine 
whether there is a reasonable expectation that an increase in the 
outdoor temperature would increase temperatures in their indoor work 
site, thereby exposing employees to heat at or above the initial heat 
trigger.
    Employers would be required to develop a monitoring plan that 
covers each work area they identified in the prior step. The monitoring 
plan is intended to determine when employees are exposed (e.g., 
specific times of day, during certain processes, certain months of the 
year) to heat at or above the initial and high heat triggers for each 
work area. When developing a monitoring plan(s), employers would need 
to take into account the circumstances that could impact heat 
conditions specific to each work area and work site. The monitoring 
plan(s) would need to be included in the employer's HIIPP.

[[Page 70777]]

    In complying with proposed paragraph (d)(3)(ii), employers would 
need to outline in their monitoring plan how they will monitor either 
heat index or WBGT using on-site monitors that are set up at or as 
close as possible to the work area(s) identified under paragraph 
(d)(3)(i). OSHA intends the phrase ``as close as possible'' to mean the 
closest possible location that won't otherwise create inaccurate 
measurements. The employer should ensure that their monitoring plan 
outlines the appropriate frequency of measurements, which should be of 
sufficient frequency to determine with reasonable accuracy employees' 
exposure to heat. For example, if the employer determines there is only 
a reasonable expectation that employees are or may be exposed to heat 
at or above the initial heat trigger when a certain process is 
happening or during certain times of the year, then they would only 
need to monitor when that process is happening or during that time of 
the year.
    Employers using heat index as their heat metric could either use 
heat index monitors or measure temperature and humidity with separate 
devices. In the latter situation, these employers would need to use a 
heat index calculator, such as the one provided on the NWS website 
(NWS, 2023), to calculate heat index from the separate temperature and 
humidity readings. Employers using WBGT as their heat metric would need 
to take into account differences in radiant heat and air movement 
between work areas when deciding whether a single measurement can be 
used for multiple work areas. For example, measurements of WBGT in a 
work area without a radiant heat source should not be applied to 
another work area that is near a radiant heat source. Regardless of 
which metric they choose to use, employers should consult user manuals 
and ensure devices are calibrated and in working order. Employers 
should follow the device manufacturer's manual when conducting 
monitoring.
    If there are multiple work areas where there is a reasonable 
expectation that employees are or may be exposed to heat at or above 
the initial heat trigger at a work site, the employer could conduct 
representative sampling instead of taking measurements at each 
individual work area. If using this approach, the employer would be 
required to sample the work area(s) expected to be the hottest. For 
example, this may involve monitoring the work area closest to a heat-
generating process. The employer cannot put a monitoring device in a 
work area known or expected to be cooler and consider that 
representative of other work areas.
    If any changes occur that could increase employee exposure to heat 
(i.e., a change in production, processes, equipment, controls, or a 
substantial increase in outdoor temperature which has the potential to 
increase heat exposure indoors), proposed paragraph (d)(3)(iii) would 
require that the employer must evaluate any affected work area(s) to 
identify where there is reasonable expectation that employees are or 
may be exposed to heat at or above the initial heat trigger. Examples 
of changes that could increase employee exposure to heat include the 
installation of new equipment that generates heat in a work area that 
didn't previously have heat-generating equipment or a local heat wave 
that increases the heat index in a warehouse without air-conditioning. 
The employer would be required to update their monitoring plan or 
develop and implement a monitoring plan, in accordance with paragraph 
(d)(3)(ii), to account for any increases in heat exposure.
    Proposed paragraph (d)(3)(iv) would require employers to involve 
non-managerial employees (and their representatives, if applicable) in 
the determination of which work areas have a reasonable expectation of 
exposing employees to heat at or above the initial heat trigger (which 
is described in paragraph (d)(3)(i)). Employers would also be required 
to involve non-managerial employees (and their representatives, if 
applicable) in developing and updating the monitoring plan(s) outlined 
in paragraph (d)(3)(ii) through (iii). One example of this involvement 
would be employees providing input in identifying processes or 
equipment that give off heat and times of the day or year when certain 
areas of the building feel uncomfortably hot and warrant monitoring. 
Employees are often the most knowledgeable about the conditions in 
which they work and their involvement will help ensure the accuracy and 
sufficiency of the employer's monitoring plan(s).
    Proposed paragraph (d)(4) specifies that the heat metric (i.e., 
heat index or WBGT) that the employer chooses to monitor determines the 
applicable initial and high heat triggers under the standard. 
Specifically, as defined in paragraph (b), if the employer chooses to 
monitor heat index, they would be required to use the initial heat 
trigger of 80 [deg]F (heat index) and the high heat trigger of 90 
[deg]F (heat index). If the employer chooses to use WBGT, they would be 
required to use the NIOSH Recommended Alert Limit (RAL) as the initial 
heat trigger and the NIOSH Recommended Exposure Limit (REL) as the high 
heat trigger. As outlined in paragraph (c), the employer would be 
required to identify which heat metric they are monitoring in their 
HIIPP. If they do not do this, proposed paragraph (d)(4) specifies that 
the initial and high heat trigger will be based on the heat index.
    Proposed paragraph (d)(5) would provide an exemption from 
monitoring requirements for employers who choose to assume that their 
employees are exposed to heat at or above both the initial and high 
heat triggers. In these cases, employers would not need to conduct 
monitoring, but they would be required to provide all controls outlined 
in paragraphs (e) and (f) while making this assumption. For the period 
of time that employers choose to make this assumption and are therefore 
exempt from monitoring requirements, they would not be required to keep 
records of monitoring data (see paragraph (i), Recordkeeping).
I. Requests for Comments
    OSHA requests comments and evidence regarding the following:
     Whether the proposed requirement to monitor outdoor work 
areas with ``sufficient frequency to determine with reasonable accuracy 
employees' exposure to heat'' is adequate or whether the standard 
should specify an interval of monitoring (and if so, what frequency and 
why);
     Whether OSHA should specify an interval of monitoring for 
indoor work areas (and if so, what frequency and why);
     Whether the standard should include a specific increase in 
outdoor temperature that would trigger the requirements in paragraph 
(d)(3)(iii) for indoor work areas, rather than the trigger being a 
``substantial increase'', and if so, what magnitude of increase;
     Whether there could be situations in which a lack of 
cellular service prevents an employer from using weather forecasts or 
real-time predictions, and if so, what alternatives would be 
appropriate;
     Whether the standard should require specifications related 
to monitoring devices (e.g., in accordance with user manuals, properly 
calibrated) and whether the standard should specify a permissible 
accuracy level for monitoring devices; and
     Whether the standard should further specify which sources 
of forecast data employers can use to comply with paragraph (d)(1)(i) 
and if so, what criteria should be used.

[[Page 70778]]

E. Paragraph (e) Requirements at or Above the Initial Heat Trigger

I. Timing
    Paragraph (e) of the proposed standard would establish requirements 
when employees are exposed to heat at or above the initial heat 
trigger. As discussed in Section V.B., Basis for Initial and High Heat 
Triggers, OSHA has preliminarily determined that the experimental and 
observational evidence support that heat index triggers of 80 [deg]F 
and 90 [deg]F are highly sensitive and therefore highly protective of 
employees. Exposures at or above the initial heat trigger, a heat index 
of 80 [deg]F or a corresponding wet bulb globe temperature equal to the 
NIOSH Recommended Alert Limit, would require the employer to provide 
the protections outlined in paragraphs (e)(2) through (10).
    The employer would only be required to provide the specified 
protections during the time period when employees are exposed to heat 
at or above the initial heat trigger. In many cases, employees may only 
be exposed at or above the initial heat trigger for part of their work 
shift. For example, employees who work outdoors may begin work at 9 
a.m. and finish work at 5 p.m. If their exposure is below the initial 
heat trigger from 9 a.m. until 12 p.m., and at or above the initial 
heat trigger from 12 p.m. to 5 p.m., the employer would only be 
required to provide the protections specified in this paragraph from 12 
p.m. to 5 p.m. Additional protective measures, outlined in paragraph 
(f) Requirements at or above the high heat trigger, would be required 
when employees are exposed to heat at or above the high heat trigger.
II. Drinking Water
    Paragraph (e)(2) of the proposed standard would establish 
requirements for drinking water when employees are exposed to heat at 
or above the initial trigger. The proposed requirements of paragraph 
(e)(2) are in addition to the requirements in existing OSHA sanitation 
standards applicable to the employer, including the general industry 
sanitation standard (29 CFR 1910.141); construction industry sanitation 
standard (29 CFR 1926.51); field sanitation standard (29 CFR 1928.110); 
shipyard employment sanitation standard (29 CFR 1915.88); marine 
terminals sanitation standard (29 CFR 1917.127); and temporary labor 
camp standard (29 CFR 1910.142). In addition to requirements for 
drinking water, these standards require access to toilet facilities, 
which is important to ensure that employees are not discouraged from 
drinking adequate amounts of drinking water. As discussed in Risk 
Reduction, Section V.C., drinking water has been shown to be an 
effective intervention for preventing dehydration, heat strain, and 
HRI. It allows employees to replace fluids lost by sweat and is 
necessary to maintain blood volume for cardiovascular function and 
thermoregulation.
    Proposed paragraph (e)(2)(i) would require that employers provide 
access to potable water that is placed in locations readily accessible 
to employees. To ensure employees have sufficient drinking water 
whenever needed, the drinking water should be located as close as 
possible to employees, to facilitate rapid access. Employers could 
comply with this provision by providing water coolers or food grade 
jugs on vehicles if drinking water fountains or taps are not nearby, or 
by providing bottled water or refillable water bottles so that 
employees always have access to water. Employers supplying water 
through a common source such as a tap or jug would have to provide a 
means for employees to drink the water. This could include providing 
disposable cups or single-user refillable water bottles. Under OSHA's 
sanitation standards, common drinking cups or other shared utensils are 
prohibited. Open containers such as barrels, pails, or tanks for 
drinking water from which water must be dipped or poured, whether or 
not they are fitted with a cover, are also prohibited under these 
standards. In cases where employers provide single-user, refillable 
water bottles, they should keep extra bottles or disposable cups on 
hand in case employees misplace or forget to bring the bottle the 
employer provided them.
    OSHA notes that water would not be readily accessible if it is in a 
location inaccessible to employees (e.g., the drinking water fountain 
is inside a locked building or trailer). Water would also not be 
readily accessible if it is placed at a distant or inconvenient 
location in relation to where employees work. OSHA expects that 
employers will have incentive to place the drinking water as close to 
employees as feasible to minimize the amount of time needed to access 
water, which must be paid. Explanation of Proposed Requirements for 
paragraph (j) Requirements implemented at no cost to employees).
    Proposed paragraph (e)(2)(ii) would require that employers provide 
access to potable water that is suitably cool. As discussed in Risk 
Reduction, Section V.C., the temperature of drinking water impacts 
hydration levels, as cool or cold water has been found to be more 
palatable than warm water, thus leading to higher consumption of cool 
water and decreased risk of dehydration. Additional evidence 
highlighted in Risk Reduction, Section V.C., shows that cool fluid 
ingestion has beneficial effects for reducing heat strain. The 
requirement that drinking water be ``suitably cool'' is consistent with 
OSHA's existing field sanitation standard (29 CFR 1928.110(c)(1)(ii)) 
and with California's heat standard for outdoor workplaces (Cal. Code 
Regs. tit. 8, section 3395). OSHA has previously stated that to be 
suitably cool, the temperature of the water ``must be low enough to 
encourage employees to drink it and to cool the core body temperature'' 
(Field Sanitation, 52 FR 16050, 16087 (May 1, 1987)). Employers could 
comply with this provision by providing drinking water from a tap or 
fountain that maintains a cooler temperature, providing water in 
coolers or by providing ice or ice packs to keep drinks cool.
    In addition to providing palatable and potable water, the NACOSH 
Heat Injury and Illness Prevention Work Group recommended that 
employers consider providing electrolyte supplemental packets that can 
be added to water or electrolyte-containing sports drinks (NACOSH 
Working Group on Heat, 2023). While employers could choose to offer 
electrolyte supplements or electrolyte-containing sports drinks, they 
would not be required under the standard. Providing electrolyte 
supplements or sports drinks alone would not meet the proposed 
requirement. OSHA has preliminarily determined that electrolyte 
supplementation may not be necessary in a majority of situations if 
workers are consuming adequate and regular meals (NIOSH, 2017a). OSHA 
has also received feedback from stakeholders that some workers may be 
unable to consume certain electrolyte supplements or solutions due to 
their sugar content.
    Proposed paragraph (e)(2)(iii) would require that employers provide 
access to one quart of drinking water per employee per hour. Employers 
could comply with this provision by providing access to a drinking 
water tap or fountain that has a continuous supply of drinking water, 
or providing coolers or jugs that are replenished with water as the 
quantity diminishes. As discussed in more detail in Section V.C., Risk 
Reduction, that volume of water intake ensures adequate replenishment 
of fluids lost through sweat to avoid a substantial loss in total body 
water content for employees working in the

[[Page 70779]]

heat. OSHA is specifying the amount of water that employers need to 
provide to employees, not an amount that employees need to drink. 
However, as discussed in the Explanation of Proposed Requirements for 
paragraphs (f)(3) and (h), the employer must inform employees of the 
importance of drinking water to prevent HRIs during initial training, 
annual refresher training, and whenever the high heat trigger is met.
    Finally, in accordance with paragraph (j) of the proposed standard, 
all drinking water requirements must be implemented at no cost to 
employees. Accordingly, employers may not charge employees for the 
drinking water required by paragraph (e)(2) nor for the equipment or 
supplies needed to access it.
A. Requests for Comments
    OSHA requests comments and information on the following:
     Whether OSHA should require a specific temperature or 
ranges of temperature for drinking water as some State regulations do 
(e.g., Colorado requires that drinking water is kept 60 [deg]F or 
cooler);
     Whether the agency should require the provision of 
electrolyte supplements/solutions in addition to water;
     Whether the requirement to provide a minimum of 1 quart 
per hour per employee is appropriate; and
     Whether there are any challenges to providing the required 
amount of drinking water (e.g., for employees who work on foot in 
remote areas) and, if so, alternatives that OSHA should consider.
III. Break Area(s) at Outdoor Work Sites
    Paragraph (e)(3) contains the proposed requirements for outdoor 
break areas when temperatures meet or exceed the initial heat trigger. 
Adequate break areas where employees can hydrate, remove PPE, and cool 
down is considered a vital component in preventing HRIs and necessary 
part of a multilayered strategy to control exposure to high heat. The 
requirements for both outdoor and indoor break areas in this proposed 
standard are in addition to employers' obligations under OSHA's 
sanitation standards (29 CFR 1910.141, 1915.88, 1917.127, 1918.95, 
1926.51, 1928.110). Because the sanitation standards address workplace 
hazards other than heat exposure, employers must continue to comply 
with their obligations under those standards. OSHA highlights these 
sanitations standards because employees are likely to eat and drink 
water in the indoor break areas, which may implicate certain provisions 
of these standards.
    Specifically, proposed paragraph (e)(3) requires employers to 
provide one or more employee break areas at outdoor work sites that can 
accommodate the number of employees on break, is readily accessible to 
the work area(s) and has either shade (paragraph (e)(3)(i)), or air-
conditioning if in an enclosed space (paragraph (e)(3)(ii))). As 
explained more in detail in Section V.C., Risk Reduction, shade reduces 
exposure to radiant heat which can contribute to heat stress and lead 
to heat strain and HRI. Further, air-conditioning is effective in 
reducing heat stress and resulting heat strain because it reduces 
exposure to heat. Accordingly, OSHA has preliminarily determined that 
requirements for break areas, including the use of controls to 
facilitate cooling while employees are on break, are effective at 
preventing HRIs among workers and should be included in the proposed 
standard. This determination is supported by NIOSH's criteria for a 
recommended standard, several State standards, and existing guidance 
(Cal. Code Regs. tit. 8, section 3395 (2024); 7 Colo. Code Regs. 
section 1103-15:3 (2023); Or. Admin. R. 437-002-0156 (2024); Or. Admin. 
R. 437-004-1131 (2024); Wash. Admin. Code 296-307-09747 (2023); NIOSH, 
2016).
    Proposed paragraph (e)(3) would require the employer to ensure the 
break area(s) can accommodate all employees on break. This provision is 
intended to ensure that all employees taking rest breaks that employers 
would need to provide under proposed paragraphs (e)(8) and (f)(2) are 
able to do so in an appropriate break area(s). If the break area cannot 
accommodate the number of employees on break, some employees may not 
have access to adequate cooling controls while on break, increasing 
their risk of HRIs. In addition, adequate space allows for ventilation 
and airflow, contributing to a more effective cooling.
    While OSHA is not proposing a minimum square footage requirement 
per employee, break areas that can only fit the anticipated number of 
employees on break if employees stand shoulder to shoulder, or in such 
close proximity that heat cannot dissipate, would not be large enough 
to accommodate the number of employees on break. Break areas that are 
not large enough to allow employees to move in and out freely or access 
necessary amenities, such as water and air-conditioning or shade, would 
also not be considered large enough to accommodate the number of 
employees on break.
    Proposed paragraph (e)(3) does not require that the break area(s) 
be able to accommodate an employer's entire workforce at the same time. 
However, the employer must evaluate the needs of the work site and 
ensure the break area(s) is large enough to accommodate all employees 
reasonably expected to be on break at the same time. When making this 
determination, employers would need to consider factors such as how 
many employees are reasonably expected to be taking breaks to prevent 
overheating under proposed paragraph (e)(8) at any given time, as well 
as the breaks required under proposed paragraph (f)(2) (e.g., are 
paragraph (f)(2) breaks staggered or will large groups of employees be 
taking them at the same time?). However, the minimum frequency and 
duration of breaks under paragraph (f)(2) must be met.
    Similarly, where an employer has multiple break areas on-site, OSHA 
does not expect each of these multiple break areas to be able to 
accommodate an employer's entire workforce. Instead, OSHA expects that 
employers who utilize multiple break areas will determine the number of 
employees anticipated to access each break area and ensure the break 
areas are sufficient in size to accommodate the need for break space in 
each location. When making this determination, employers would need to 
consider factors such as the distribution of employees across different 
areas and any employee movement throughout the areas during a work 
shift.
    OSHA also acknowledges that some employers may have facilities 
where both outdoor and indoor work occurs. OSHA requests comments on 
whether the agency should permit all employees in these facilities to 
utilize indoor break areas.
    Proposed paragraph (e)(3) would require that break areas be readily 
accessible to the work area(s). It is important that break areas be 
readily accessible to ensure that employees can take breaks promptly, 
particularly in situations where employees are experiencing early 
symptoms of HRIs, as quick access to a break area can help limit the 
further progression of illness. In addition, break areas within close 
proximity to employees encourages use. OSHA does not expect the 
employer to have break areas located immediately adjacent to every 
employee and understands that exact distance may vary depending on 
factors such as the size and layout of the workplace, the number of 
employees, and the nature of the work being performed.
    Locations that are so far from work area(s) that they deter 
employees from taking breaks would not be considered readily 
accessible. When determining

[[Page 70780]]

the location of the break area(s), the employer would be expected to 
evaluate the duration of travel to the area. Break areas requiring more 
than a few minutes to reach would increase the heat stress on employees 
as they walk to the area and thus not be considered reasonably 
accessible. The break area must be situated close enough to work areas 
to minimize the time and effort required for employees to access it. 
Break areas should be as close as possible to employees so that an 
employee in distress could easily access the area to promptly cool 
down. OSHA expects that employers will have incentive to place the 
break areas as close as practical to the work areas to minimize travel 
time, which must be paid (see Explanation of Proposed Requirement for 
paragraph (j) Requirements implemented at no cost to employees).
    For mobile work sites, such as in road construction or utility 
work, the employer would be expected to relocate the break area as 
needed to ensure it is readily accessible to employees or ensure each 
work site has its own break area for use. This requirement would also 
apply to large work sites where employees are continually changing 
their work area, such as in agricultural work. The employer would be 
required to pay employees their normal rate of pay for time to get to 
the break area, as well as the time on break (see the Explanation of 
the Proposed Requirements for paragraph (j)).
    In addition to ensuring the break area(s) is large enough to 
accommodate all employees on break and readily accessible to the work 
area(s), employers would have to provide at least one of the following: 
shade (paragraph (e)(3)(i)); or air-conditioning, if in an enclosed 
space (paragraph (e)(3)(ii)). As discussed above, break areas are 
intended to provide employees a spot to cool down and reduce body 
temperature. Also, controls such as shade and air-conditioning are 
proven methods to prevent HRIs. Without controls such as these in 
place, break areas could become uncomfortable and even continue to 
expose individuals to the risk of HRI. OSHA understands that the scope 
of the standard includes a broad variety of outdoor industries, and 
that even within one industry, workplaces can be vastly different. The 
proposed requirements for outdoor break areas give employers 
flexibility in their compliance.
    Paragraph (e)(3)(i) of the proposal outlines the requirements for 
employers who use shade. The provision would require that the break 
area have artificial shade (e.g., tent, pavilion) or natural shade 
(e.g., trees), but not shade from equipment, that provides blockage of 
direct sunlight and is open to the outside air. By incorporating shade 
into break areas, whether through natural foliage, awnings, or 
umbrellas, employees are able to reduce exposure to radiant heat and 
benefit from conditions that are more conducive to increasing 
evaporative cooling as air moves across the skin. The benefits of 
shaded break areas have also been recognized by several States and 
incorporated into State standards, including California, Colorado, 
Oregon, and Washington (Cal. Code Regs. tit. 8, section 3395 (2024); 7 
Colo. Code Regs. section 1103-15:3 (2023); Or. Admin. R. 437-002-0156 
(2024); Or. Admin. R. 437-004-1131 (2024); Wash. Admin. Code 296-307-
09747 (2023)).
    To ensure shade is effective, OSHA would require the shade to block 
direct sunlight for the break area. OSHA does not expect employers to 
measure shade density using shade meters or solarimeters. As defined 
under proposed paragraph (b) Shade means the blockage of direct 
sunlight, such that objects do not cast a shadow in the area of blocked 
sunlight. Therefore, verifying that employees' shadows are obstructed 
from being visible due to the presence of shade would be sufficient. In 
addition, shaded break area(s) must be open to the outside air. To 
satisfy this requirement, the shaded break area must be sufficiently 
open to the outside air to ensure that air movement across the skin 
(promoting the evaporation of sweat) can occur and to prevent the 
buildup of humidity and heat that can become trapped due to limited 
airflow and stagnant air. For example, a pop-up canopy with one 
enclosed side would comply with the provisions for a shade structure; 
however, a closed trailer having four sides and a roof would not. 
Employers could also incorporate other cooling measures, such as fans 
or misting devices, in their shaded break area, although the proposed 
standard does not require them to do so.
    Both portable and fixed shade would be permitted to comply with the 
proposed requirements under (e)(3)(i). However, as stated above, 
employers must ensure shaded break areas remain readily accessible to 
employees. At mobile work sites or work sites where employee move to 
various locations throughout the day, such as, but not limited to those 
commonly found in agriculture, landscaping, forestry, and utility work, 
employers would need to ensure that shade structures are relocated near 
the work area as needed or that natural sources of shade (e.g., from 
trees) are readily available at each work location. OSHA understands 
that in some mobile outdoor work environments shade structures may not 
be practical and employers may wish to utilize the flexibility of shade 
provided by large vehicles that are already on-site. Large vehicles 
such as trucks and vans which are used to transport employees or goods 
to the work site, but not as part of the work itself could be used as 
shade as long as the vehicle is not running. OSHA is not allowing the 
use of equipment used in work process, such as tractors, for shade due 
to the risk of accidental run-overs caused by the start-up and movement 
from operators who are not aware of the presence of workers nearby. 
Additionally, equipment used in work processes is likely to emit 
radiant heat after use, which may impede employee cooling. However, 
shade provided by buildings could be used, provided it is reasonably 
accessible to employee work areas. Additionally, as previously 
explained, the break area(s) must be large enough to accommodate all 
employees on break. Therefore, employers utilizing shade cast by 
buildings or trees would need to consider the path of shade movement 
throughout the day to ensure adequate areas of shade coverage are 
maintained and the shade is able to accommodate all employees on break.
    Paragraph (e)(3)(ii) of the proposal describes the requirements for 
the use of air-conditioned break areas. Specifically, the proposed 
provision indicates that a break area could be an area that has air-
conditioning if that area is in an enclosed space like a trailer, 
vehicle, or structure. As with the shaded areas, the air-conditioned 
break area would need to be large enough to accommodate the number of 
employees on rest breaks and be readily available. The use of air-
conditioned spaces is consistent with State requirements and existing 
guidance. In their State regulations, both Colorado and Washington 
include the use of an air-conditioned site, such as a vehicle or 
structure, as an alternative to providing shade for employee rest 
breaks (7 Colo. Code Regs. section 1103-15:3 (2023); WA, 2008b; Wash. 
Admin. Code 296-307-09747 (2023). It is well established that the use 
of air-conditioned spaces reduces the air temperature employees are 
exposed to (NIOSH, 2016).
    Employers using air-conditioned vehicles as a break area would need 
to ensure that the vehicle remains readily available during work 
periods when the initial heat trigger is met or exceeded. For mobile 
employees, such as delivery drivers, employers could have employees 
take breaks in an air-conditioned convenience store,

[[Page 70781]]

restaurant, or similar establishment as long as all other requirements 
for break areas are met.
A. Requests for Comments
    OSHA seeks comments and additional information whether it should 
further specify break area requirements (e.g., square footage per 
employee), and what those requirements should be. Also, OSHA seeks 
additional comments on break areas where employers have both indoor and 
outdoor work areas including:
     Whether OSHA should maintain separate break area 
requirements for these employees;
     Whether OSHA should allow outdoor employees in these 
facilities to utilize indoor break areas under paragraph (e)(4); and
     Whether OSHA should limit the use of indoor break areas to 
those that are equipped with air-conditioning.
    OSHA seeks comments and additional information regarding the use of 
shade, including:
     Whether OSHA appropriately defined shade; if not, how 
should OSHA define shade for outdoor break areas;
     Whether there are situations where shade is not protective 
and should not be permitted; and in these cases, what should be 
required for break areas;
     Whether there are additional options for shade that are 
protective, but which OSHA has not included;
     Whether there are situations when trees are not 
appropriate for use as shade and other measures should be required;
     Whether there are situations when employers should be 
permitted to use equipment as shade; in those situations, how would 
employers mitigate other safety concerns such as run-over incidents;
     Whether there are situations when employers should not be 
able to use large vehicles as shade or concerns, including those 
related to safety, with generally allowing the use of large vehicles 
for shade; and
     Whether there are situations when artificial shade should 
not be permitted, such as during high winds.
    OSHA seeks comments and additional information regarding the use of 
air-conditioned spaces, including:
     Whether OSHA should define or specify the levels at which 
air-conditioning must operate; and
     Whether OSHA should require that break rooms and vehicles 
used for breaks be pre-cooled prior to the start of the employee's 
break.
    OSHA seeks comments and additional information regarding the use of 
other cooling strategies (beside shade and air-conditioning) that could 
be used in break areas, including:
     Whether there are other control options that would be both 
as effective as shade at reducing heat strain and feasible to 
implement;
    OSHA seeks comments and additional information regarding break area 
requirements for mobile workers:
     OSHA did not include separate requirements and seeks 
additional information on the feasibility and effectiveness of the 
proposed controls listed under paragraph (e)(3) including the use of 
vehicles as a break area; and
     Whether there are control options OSHA should require for 
vehicles, either when used for work activities or when used as a break 
area.
IV. Break Area(s) at Indoor Work Sites
    Paragraph (e)(4) of the proposed standard outlines the requirements 
for break areas at indoor work sites. Specifically, it would require 
that the employer provide one or more area(s) for employees to take 
breaks (e.g., break room) that is air-conditioned or has increased air 
movement and, if appropriate, de-humidification; can accommodate the 
number of employees on break; and is readily accessible to the work 
area(s). As explained above in the Explanation of Proposed Requirements 
for paragraph (e)(3), the requirements for both outdoor and indoor 
break areas in this proposed standard are in addition to employers' 
obligations under OSHA's sanitation standards (29 CFR 1910.141, 
1915.88, 1917.127, 1918.95, 1926.51, 1928.110).
    Information regarding compliance with the requirements that break 
area(s) be large enough to accommodate all employees on break and 
readily accessible can be found in the Explanation of Proposed 
Requirements for paragraph (e)(3). Break area(s) at indoor work sites 
will often likely be specific rooms in a facility (e.g., a break room). 
To ensure that the break areas are readily accessible, employers would 
need to make sure that employees can enter the break areas for heat-
related breaks (e.g., keep the break room unlocked).
    At indoor work sites, the break area(s) must be air-conditioned or 
have a combination of increased air movement and, if appropriate, de-
humidification. The importance and effectiveness of air-conditioning 
and air movement in preventing HRIs were explained above in the 
Explanation of Proposed Requirements for paragraph (e)(3). OSHA is 
requiring de-humidification, if appropriate, in addition to increased 
air movement because humidity levels directly impact the body's ability 
to cool itself through evaporation. Humidity control is integrated into 
modern air-conditioning units and therefore OSHA is only requiring de-
humidification to be implemented in high temperature and high humidity 
environments when employers are relying on increased air movement to 
comply with this requirement. To determine when de-humidification may 
be appropriate in the context of fan use, employers should consult the 
Explanation of Proposed Requirements for paragraph (e)(6).
    To comply with the requirements under proposed paragraph (e)(4), 
employers who operate in arid environments could use evaporative or 
``swamp'' coolers as a form of air-conditioning. Note, however, that 
such coolers are not effective in humid environments. It is also 
important to note that OSHA is not requiring employers install a 
permanent cooling system. The use of portable air-conditioning units or 
high-powered fans and portable dehumidifiers in designated break areas 
could also be used to comply with requirements for break areas under 
the proposed standard. As discussed in the Explanation of Proposed 
Requirements for paragraph (e)(6), fan use when ambient temperatures 
exceed 102 [deg]F has been demonstrated to be harmful under some 
conditions and employers must evaluate humidity levels to determine if 
fan use should be avoided.
    Under the proposal, indoor break area(s) do not necessarily need to 
be located in a separate room but can be integrated within the main 
workspace. For example, in a manufacturing facility, there could be a 
designated corner or section within the main production area where 
employees could take their breaks. This break area could be demarcated 
by partitions, screens, or signage to distinguish it from the active 
work zones and be equipped with fans. Alternatively, an employer, who 
is unable to establish a break area in their main workroom because of 
sensitive or hazardous work equipment or processes, can establish a 
break area in a separate area away from the work zone, provided that 
area is readily accessible to employees. Regardless of where a break 
area is located, the break area must allow employees to cool down 
effectively and drink water to hydrate.
    For indoor workplaces that experience temperatures above the heat 
triggers but have employees who spend part of their time in air-
conditioned control booths or control rooms and part of their time in 
other, hotter areas of the facility, the employer could utilize the 
control booth/room as a break area and

[[Page 70782]]

would not need to provide a separate break area for those employees. 
Control booths/rooms are commonly found in industries such as 
manufacturing, food processing, electronics assembly, processing 
facilities, power plants, water treatment plants, and more. 
Furthermore, these spaces would qualify as break areas for other 
employees provided that the requirements for size and location are met. 
Control booths/rooms that are locked or have restricted accessibility 
would not be acceptable under the proposal.
A. Requests for Comments
    OSHA seeks comments and additional information regarding the use of 
engineering controls for indoor break areas, including:
     Whether OSHA should specify how effective engineering 
controls need to be in cooling the break area(s), including other 
measures determining effectiveness beyond temperature and humidity;
     Whether OSHA should define a temperature differential 
between work areas and break areas; and
     Whether OSHA should specify a temperature that break areas 
must be kept below.
    OSHA seeks comments and additional information regarding the use of 
other cooling strategies (besides fans and air-conditioning) that could 
be used in break areas, including:
     Whether there are other control options that would be both 
effective at reducing heat strain and feasible to implement.
    OSHA did not include an option for the use of outdoor break areas 
for indoor work sites and seeks comment and information on the use of 
outdoor break areas for employees in indoor work sites, including:
     Whether there are situations where an outdoor break area 
could be more effective at cooling and should be permitted; and
     Whether certain conditions must be provided for these 
outdoor break areas.
    OSHA seeks additional comments on break areas where employers have 
both indoor and outdoor work areas. See Explanation of Proposed 
Requirements paragraph (e)(3), Requests for Comments.
V. Indoor Work Area Controls
    Paragraph (e)(5) contains the proposed requirements for indoor work 
area controls when temperatures meet or exceed the initial heat 
trigger. Indoor work areas would be required to be equipped with a 
combination of increased air movement and, if appropriate, de-
humidification (paragraph (e)(5)(i)); air-conditioning (paragraph 
(e)(5)(ii)); or, in the case of radiant heat sources, other cooling 
measures that effectively reduce employee exposure to radiant heat in 
the work area (paragraph (e)(5)(iii)). The importance and effectiveness 
of air-conditioning and air movement (including dehumidification) in 
preventing HRIs were explained above in the Explanation of Proposed 
Requirements for paragraphs (e)(3). In addition to these, OSHA is 
permitting the use of other control measures for radiant heat sources 
because these controls result in less heat being radiated to employees.
    As discussed above in the Explanation of Proposed Requirements for 
paragraph (d)(3)(i), employers would be expected to determine which 
work areas of indoor work sites, if any, are reasonably expected to 
meet or exceed the initial heat trigger. For work areas at or above the 
trigger, such as those near heat-generating machinery, paragraph (e)(5) 
would require employers to implement work area controls. OSHA 
understands that effective control methods can vary based on workspace 
circumstances and the nature of the heat source and is therefore giving 
employers options regarding indoor work area controls. However, each 
work area with exposures at or above the initial heat trigger would 
need be to be equipped with at least one control option. Additionally, 
employers could choose to use a combination of control measures.
    Employers could use increased air movement (e.g., fans) and, if 
appropriate, de-humidification, or air-conditioning to cool the work 
area under paragraphs (e)(5)(i) and (ii). Under paragraph (e)(5)(i), 
fans could be used to increase the air movement in the work area. 
Employers could use overhead ceiling fans, portable floor fans, or 
other industrial fans to comply. Employers could also increase the air 
flow using natural ventilation by opening doors and windows, or vents, 
to allow fresh air to flow into the space, but only when doing so would 
be comparable to the use of fans. Natural ventilation would not be 
acceptable if it does not produce air movement equivalent to a fan, or 
if the outdoor temperature is such that natural ventilation increases 
the work area temperature.
    Depending on the type of work being done and the location of 
employees in a facility, employers could choose to use ventilation to 
cool the entire space or just those areas where employees are present. 
Although paragraph (e)(5) only applies to work areas, it may be more 
efficient for the employer to implement the control for an entire 
space. With either strategy, the employer should consider the facility 
layout, equipment placement, and potential obstructions to ensure 
optimal airflow when determining where to place fans. For example, an 
employer could use fans to cool a warehouse by strategically 
positioning them near entrances and exits to create airflow and 
facilitate the circulation of fresh air into the warehouse. 
Additionally, utilizing high-velocity fans along aisles or in areas 
where employees are concentrated can help dissipate heat and provide a 
cooling effect. Conversely, if employees only work in a discrete 
area(s) of a facility, an employer may choose to only provide fans in 
those work areas. For example, the employer could place fans in the 
area where employees are stationed. Adjustable fans or fans with 
oscillating features could be used in those areas to allow employers to 
direct airflow where it is most needed. Additionally, employers could 
consider installing overhead fans or mounting fans on adjustable stands 
to ensure optimal coverage and airflow distribution.
    As discussed in the Explanation of Proposed Requirements for 
paragraph (e)(4), employers using fans or relying on natural 
ventilation in humid environments would still be expected to decrease 
humidity levels where appropriate. OSHA is not proposing a specific 
temperature or humidity level be maintained in the work areas; however, 
employers should ensure that the combination of air movement and 
humidity level effectively reduces employees' heat strain. As discussed 
in the Explanation of Proposed Requirements for paragraph (e)(6), OSHA 
has preliminarily determined that under some conditions, fan use may be 
harmful when ambient temperatures exceed 102 [deg]F and employers must 
evaluate humidity levels to determine if fan use is harmful when 
temperatures reach this threshold. Employers should consult the 
Explanation of Proposed Requirements for paragraph (e)(6) to determine 
when de-humidification may be appropriate in the context of fan use.
    Under paragraph (e)(5)(ii) employers could use air-conditioning to 
meet the requirement for controlling heat exposures in indoor work 
areas. In arid environments, evaporative coolers, also known as ``swamp 
coolers,'' could be used and would be considered air-conditioners, even 
if portable. It is important to note that while an employer may choose 
to provide air-conditioning to the entire facility, they

[[Page 70783]]

would not be required to do so under the proposed standard. Employers 
who choose to provide air-conditioning under paragraph (e)(5)(ii) would 
only need to implement it in areas where employees work and are exposed 
to temperatures above the initial heat trigger. Similar to fan use, if 
employees only work from fixed or designated locations in the 
workplace, the employer would only need to provide air-conditioning to 
those spaces under paragraph (e)(5)(ii). For example, if employees work 
only from a control booth or control room, employers could choose to 
install air-conditioning in the control booth or control room to comply 
with paragraph (e)(5)(ii). Similarly, portable air-conditioning units 
could be used throughout the facility to cool smaller areas where 
employees work. For example, an employer could position portable 
evaporative coolers near the entrance of a loading dock to provide 
immediate relief from the heat when an employee is loading or unloading 
goods inside the building, or a machine shop may choose to use portable 
air-conditioners around the workstation to cool the employee. 
Alternatively, a manufacturing facility may choose to install a small, 
air-conditioned control booth for operators to work from. All of these 
options would be acceptable under the proposal.
    Under paragraph (e)(5)(iii), in indoor work areas with radiant heat 
sources, employers could choose to implement other measures that 
effectively reduce employee exposure to radiant heat in the workplace. 
Paragraph (e)(5)(iii) would allow the use of controls such as shielding 
or barriers, isolation, or other measures that effectively reduce 
employee exposure to radiant heat, in areas where employees are exposed 
to radiant heat created by heat-generating processes. The use of 
control methods for radiant heat is consistent with guidance issued by 
Minnesota regarding the implementation of their heat standard (MNOSHA, 
2009). Options for complying with this proposed provision could include 
installing shielding or barriers that are radiant-reflecting to reduce 
the amount of radiant heat to which employees would otherwise be 
exposed; isolating the source of radiant heat, such as using thermal 
insulation on hot pipes and surfaces; increasing the distance between 
employees and the heat source; and modifying the hot process or 
operation.
    If the employer chooses to utilize radiant heat controls under 
paragraph (e)(5)(iii) in lieu of air-conditioning or fan use, the 
controls would need to effectively reduce employee exposure to radiant 
heat. For example, in facilities with industrial ovens, kilns, or 
process heat, employees may be exposed to radiant heat during loading, 
unloading, or maintenance tasks. Installing shielding around these heat 
sources can help protect employees from radiant heat during these 
tasks. In another example, an employer may choose to install heat-
resistant barriers or insulating materials around welding stations to 
contain heat and prevent its transmission to adjacent work areas.
A. Requests for Comments
    OSHA seeks comments and additional information regarding the use of 
engineering controls for indoor work areas, including:
     Whether the standard should specify how effective 
engineering controls need to be in cooling the work area(s);
     Whether there are other control options (besides fan use 
or air-conditioning) that would be both effective at reducing heat 
strain and feasible to implement in cases where indoor employees are 
exposed to ambient heat; and
     Whether there are work areas where maintaining a high 
ambient temperature is necessary for the work process and, if so, how 
OSHA should address these work areas in the standard.
VI. Evaluation of Fan Use
    Paragraph (e)(6) of the proposed standard would require employers 
using fans under certain conditions to determine if fan use is harmful. 
Specifically, when ambient temperatures exceed 102 [deg]F (39.0 
[deg]C), employers using fans to comply with paragraphs (e)(4) or (5) 
would be required to evaluate the humidity levels at the work site and 
discontinue the use of fans if the employer determines that fan use is 
harmful.
    As discussed in Section V.C., Risk Reduction, researchers in the 
past 10 years have increasingly evaluated the conditions under which 
fan use becomes harmful, using both experimental and modeling 
approaches. Most of this work has assumed individuals are seated and at 
rest; to OSHA's knowledge, only one paper has evaluated the threshold 
at which fans become harmful for individuals performing physical work 
(Foster et al., 2022a). The impact of fans is determined by both air 
temperature and humidity, as well as factors influencing sweat rates. 
Researchers have demonstrated that neither heat index nor ambient 
temperature alone can be used to determine beneficial versus harmful 
fan use; instead, ambient temperature and relative humidity must both 
be known (Morris NB et al., 2019; Foster et al., 2022a).
    The 102 [deg]F threshold in proposed paragraph (e)(6) is derived 
from Figure 4 of Foster et al. 2022a and represents the lowest ambient 
temperature at which fan use has been demonstrated to be harmful in the 
researchers' model. As proposed, paragraph (e)(6) does not specify how 
employers must make the determination whether fan use is harmful above 
this threshold. However, using the other results from Figure 4 of 
Foster et al. 2022a, OSHA has developed the following table which 
identifies scenarios where the agency believes fan use would or would 
not be harmful:

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                                            Fan speed: 3.5 m/s
------------------------------------------------------------------------
                                    Humidity range:     Humidity range:
       Ambient temperature          fan use allowed      turn off fans
------------------------------------------------------------------------
102.2 [deg]F (39 [deg]C)........  15-85%............  <15% or >85%.
104.0 [deg]F (40 [deg]C)........  20-80%............  <20% or >80%.
105.8 [deg]F (41 [deg]C)........  30-65%............  <30% or >65%.
107.6 [deg]F (42 [deg]C)........  30-65%............  <30% or >65%.
109.4 [deg]F (43 [deg]C)........  35-60%............  <35% or >60%.
111.2 [deg]F (44 [deg]C)........  35-55%............  <35% or >55%.
113.0 [deg]F (45 [deg]C)........  40-55%............  <40% or >55%.
>113.0 [deg]F (>45 [deg]C)......  Discontinue all     Discontinue all
                                   fan use.            fan use.
------------------------------------------------------------------------


[[Page 70784]]

    Using the information from this table, an employer could identify 
the row most closely matching the ambient temperature of the work or 
break area and then find the corresponding humidity range for when fans 
are acceptable to use. For example, if the ambient temperature of the 
work or break area is 104 [deg]F and the relative humidity is 50%, fans 
could be used. However, if the ambient temperature of the work or break 
area is 108 [deg]F and the relative humidity is 70%, fans should not be 
used.
A. Requests for Comments
    OSHA recognizes that there are several limitations with the 
analyses by Foster et al. 2022a, and the application of those results 
for this purpose. For one, the model results reported by Foster et al. 
assume ``light clothing'' only and not ``work clothing,'' which would 
be more similar to a typical work uniform than the ``light clothing.'' 
While the empirical evidence that the researchers collected on 
individuals wearing ``work clothing'' is largely consistent with the 
modeled results presented for ``light clothing,'' there are some 
differences, such as the finding that fans are never beneficial at or 
above an ambient temperature of 45 [deg]C (113.0 [deg]F) when wearing 
``work clothing'' (which OSHA has reflected in the table). The authors' 
recommendations for fan use also included a category that represented 
scenarios in which fans have a ``minimal impact'' (i.e., the effect of 
fans on body heat storage is close to zero). OSHA has combined this 
category with the category for scenarios in which fans are beneficial 
to produce the table above. Another limitation is the assumption of a 
sweat rate of approximately 1 liter per hour (the group average from 
empirical trials in the same study). However, factors such as 
acclimatization status, age, and medical history can influence sweat 
rates, which would influence when fan use is beneficial (see Figure 6 
[panels a and b] from Foster et al., 2022a). Finally, Foster et al. 
tested a fan with a velocity of 3.5 meters per second. OSHA has 
preliminarily determined that this is a reasonable assumption but 
acknowledges that varying wind velocity would also influence when fan 
use is beneficial (see Figure 6 [panel c] from Foster et al., 2022a).
    OSHA understands the complexity and uncertainty around an 
evaluation of fan use and is therefore considering a simplified 
approach for employers to use. OSHA is requesting comments on this 
simplified approach and the assumptions underlying it.
    More specifically, OSHA requests comments regarding its preliminary 
determinations on fan use and seeks the following information:
     Whether OSHA has appropriately derived recommendations for 
fan use from Foster et al., 2022a, and whether additional data or 
research should be used to supplement or revise the recommendations;
     Whether OSHA should include the above table derived from 
Foster et al., 2022a, or a similar table, in paragraph (e)(6), either 
as a mandatory requirement or as a compliance option; and,
     Whether the standard should require alternative methods 
for cooling employees when fans are harmful, and if so, what 
alternative control measures should be used.
VII. Acclimatization
    Paragraph (e)(7) of the proposed standard would establish 
requirements to protect new and returning employees who are not 
acclimatized. Evidence indicates that new and returning employees are 
at increased risk for HRIs. As explained in Section V.C., Risk 
Reduction, employees who are new on the job are often overrepresented 
in HRI and heat-related fatality reports. Additionally, the NACOSH Heat 
Injury and Illness Prevention Work Group recommended acclimatization 
protections for new and returning employees, such as heightened 
monitoring (NACOSH Working Group on Heat, 2023), and NIOSH recommends 
an acclimatization plan that gradually increases new employees' work in 
the heat starting with 20% of the usual work duration and increasing by 
no more than 20% on each subsequent day (NIOSH, 2016). For returning 
employees, NIOSH recommends an acclimatization plan that starts with no 
more than 50% of the usual work duration of heat exposure that then 
gradually increases on each subsequent day (NIOSH, 2016). Therefore, 
OSHA has preliminarily determined that the requirements in paragraph 
(e)(7) are important for preventing HRIs and fatalities from 
occupational heat exposures among these employees.
    Proposed paragraph (e)(7)(i) would require that employers implement 
one of two options for an acclimatization protocol for new employees 
during their first week on the job. The first option that an employer 
may choose, under proposed paragraph (e)(7)(i)(A) (Option A), is a plan 
that, at a minimum, includes the measures required at the high heat 
trigger set forth in paragraph (f), when the heat index is at or above 
the initial heat trigger during the employee's first week of work. 
Proposed paragraph (f)(2) requires a minimum 15-minute paid rest break 
at least every two hours in the break area that meets the requirements 
of the proposed standard, proposed paragraph (f)(3) requires 
observation for signs and symptoms of heat-related illness, and 
proposed paragraph (f)(4) requires providing hazard alerts with 
specified information about heat illness prevention and how to seek 
help if needed. See the Explanation of Proposed Requirements for 
paragraph (f), Requirements at the high heat trigger, for a detailed 
explanation of the requirements of that section. Option A gives 
employers flexibility to choose an option that works best for their 
work site while still making sure that employees are informed, are 
under observation, and receive breaks, all of which will help better 
equip employers and employees to monitor and mitigate the effects of 
heat exposure in situations where the gradual acclimatization option 
may not be practical. While this option does not require gradual 
exposure, OSHA believes that, in situations where gradual exposure may 
not be practical, rest breaks, observation, and hazard alerts will help 
protect new workers as they adjust to heat during their first week of 
work.
    The second option that an employer may choose, under proposed 
paragraph (e)(7)(i)(B) (Option B), would require a gradual exposure to 
the heat at or above the initial heat trigger to allow for 
acclimatization to the heat conditions of the workplace. The gradual 
exposure protocol would involve restricting employee exposure to heat 
to no more than 20% of a normal work shift exposure duration on the 
first day of work and increasing exposure by 20% of the work shift 
exposure duration on each subsequent day from day 2 through 4. This is 
consistent with NIOSH's recommended acclimatization plan for new 
employees (NIOSH, 2016).
    Employers may satisfy Option B requirements by utilizing some of 
the employees' work time in ways that do not require exposure to heat 
at or above the initial heat trigger. Examples include completing 
training activities or filling out work-related paperwork in an air-
conditioned building. Employers may also fulfill this requirement 
through task replacement, whereby an employee completes another 
necessary task in an area that does not require exposure at or above 
the initial heat trigger (e.g., office work).
    Additionally, if the temperature of the work site fluctuates such 
that the initial heat trigger is only exceeded for a portion (e.g., 2 
hours) of the work shift

[[Page 70785]]

on some or all of the days during the initial week of work, employers 
choosing Option A would only be required to implement the requirements 
of paragraph (f) during those time periods. If they choose the gradual 
heat exposure option for acclimatization, employers would need to 
coordinate the employees' heat exposure for those days with the parts 
of the day that are expected to meet or exceed the initial heat 
trigger.
    Under proposed paragraph (j), employers would be required to 
implement the acclimatization protocols at no cost to employees. This 
means that employers could not relieve employees from duty after the 
allotted time of heat exposure under the acclimatization protocol and 
not pay them for the remainder of the work shift. Because benefits 
would also be considered compensation, this would mean that an employer 
could not use an employee's paid leave to cover the hours not worked 
during the acclimatization period.
    Proposed paragraph (e)(7)(ii) would require that employers 
implement one of two options for an acclimatization protocol for 
returning employees who have been away from the job for more than 14 
days, during their first week back on the job.
    The first option that an employer may choose, under proposed 
paragraph (e)(7)(ii)(A) (Option A), is an employer-developed plan, that 
at a minimum, includes the measures that would be required under 
proposed paragraph (f) whenever the initial heat trigger is met or 
exceeded, during the employee's first week of returning to work. See 
explanation above for new employees and the Explanation of Proposed 
Requirements for paragraph (f), Requirements at the High Heat Trigger, 
of the proposed standard for a detailed explanation of the requirements 
of that section.
    The second option that an employer may choose under proposed 
paragraph (e)(7)(ii)(B) (Option B), is a protocol that requires a 
gradual exposure to heat at or above the initial heat trigger to allow 
for acclimatization to the heat conditions of the workplace. The 
gradual exposure protocol would restrict employee exposure to heat to 
no more than 50% of a normal work shift exposure duration on the first 
day of work, 60% on the second day of work, and 80% of the third day of 
work. This is consistent with NIOSH's recommended acclimatization plan 
for returning employees (NIOSH, 2016). Employers may satisfy these 
requirements by utilizing employees' work time in ways that do not 
require heat exposure at or above the initial heat trigger, as 
described above for new employees.
    For occupations where returning employees may have shift schedules 
such as two weeks on and then two weeks off, the acclimatization 
protocol requirement would not go into effect because the two weeks off 
would not exceed 14 days. However, in situations where time off exceeds 
14 days, the requirement would apply.
    Proposed paragraph (e)(7)(iii) would set forth an exception to 
acclimatization requirements of paragraphs (e)(7)(i) and (ii) if the 
employer can demonstrate that the employee consistently worked under 
the same or similar conditions as the employer's working conditions 
within the previous 14 days. Same or similar conditions means that new 
employees must have been doing work tasks that are similar or higher in 
level of exertion to the tasks that are required in the new job and 
that they conducted these tasks in similar or hotter heat conditions 
than the new job (e.g., at or above the heat index for current 
conditions in the new job). Employers should not assume that employees 
who recently came from climates that are perceived to be similar or 
hotter (e.g., Mexico) were actually exposed to similar or hotter 
conditions because climate can vary dramatically based on factors such 
as elevation levels and humidity. Therefore, employers could check 
weather records to determine heat indices for the location that the 
employee worked at during the previous two weeks to determine if the 
employee was actually exposed to conditions at least as hot as in the 
new position.
    In determining if tasks the employee conducted in the past two 
weeks were similar or higher in level of exertion to the tasks that are 
required in the new job, employers could generally consider factors 
such as weight carried and intensity of activity (e.g., walking versus 
climbing). For example, picking tomatoes and picking watermelons would 
generally not be considered similar tasks because of the heavier weight 
of the watermelons. However, picking tomatoes and picking cucumbers 
could generally be considered similar tasks if other job conditions are 
similar. Installing telephone wires on poles and laying out 
communication wires in a trench dug using machinery would generally not 
be considered similar to laying out communication wires in a trench dug 
manually because of the greater work intensity involved with digging a 
trench manually. Laying communication wire in a pre-dug trench and 
conducting inspections on the ground might be considered similar tasks 
if both tasks primarily involve walking. Landscaping work involving 
weeding and laying out mulch versus hand digging trenches for drainage 
systems would generally not be considered similar tasks because of the 
greater work involved in digging trenches. However, hand digging 
trenches for drainage and hand digging holes to install trees and 
shrubs could generally be considered similar tasks if those are the 
primary tasked performed throughout the workday.
    The employee must have engaged in similar work activities in the 
similar heat conditions consistently over the preceding 14 days. OSHA 
intends ``consistently'' to mean the employee engaged in the task for 
at least two hours per day on a majority of the preceding 14 days. This 
aligns with recommendations from NIOSH (NIOSH, 2016).
    Examples of when this exception would not apply include when new 
employees' previous positions, which included similar heat conditions 
and exertion levels, ended longer than 14 days ago, when new employees' 
previous positions ended within the last 14 days and involved similar 
work tasks but in cooler conditions, or when new employees' previous 
positions ended within the last 14 days and involved hotter conditions 
but less exertion. The exemption would also not apply if new employees' 
previous positions ended less than 14 days ago but they were not 
performing similar work tasks in similar heat conditions for at least 
two hours per day on a majority of the preceding 14 days.
    To demonstrate that a new employee consistently worked under the 
same or similar conditions as the employer's working conditions within 
the prior 14 days, the employer could obtain information directly from 
the new employee to confirm the requirements of proposed paragraph 
(e)(7) are met considering the explanation of same or similar working 
conditions provided above. The employer could ask questions verbally or 
in writing about the prior work (i.e., timing, location, duration, type 
of work). If an employer asked new employees ``in the past 14 days, did 
you consistently work under the same or similar conditions as the 
employer'' but did not ask for any supporting details, the requirement 
would not be satisfied.
A. Requests for Comments
    OSHA requests comments and evidence regarding the following:
     Data or examples of successful implementation of an 
acclimatization program;

[[Page 70786]]

     Whether the term ``same or similar conditions'' is 
sufficiently clear so that employers know when the exception to the 
acclimatization requirement would apply for new employees, and if not, 
how should OSHA clarify the requirement;
     Whether a minimum amount of heat exposure to achieve 
acclimatization should be specified under Option B, the gradual 
acclimatization option;
     Whether the requirement to demonstrate that an employee 
consistently worked under the same or similar conditions as the 
employer's working conditions within the prior 14 days is sufficiently 
clear, and if not, how should OSHA clarify the requirement;
     Whether the standard should require acclimatization 
protocols during local heat waves, and if so, how OSHA should define 
heat waves;
     Whether the standard should require annual acclimatization 
of all employees at the beginning of each heat season (e.g., the first 
hot week of the year) and approaches for doing so;
     Examples that OSHA should consider of acclimatization 
protocols for industries or occupations where it may not be appropriate 
for an employee to conduct heat-exposed work tasks during the first 
week on the job (e.g., what activities would be appropriate for these 
workers to achieve acclimatization);
     Data or examples that OSHA should consider in determining 
if acclimatization should be required in certain situations for 
existing employees and examples of successful acclimatization programs 
for such employees;
     Which option (i.e., following requirements of the high 
heat trigger or gradual increase in exposure to work in heat) presented 
in the proposal would employers implement and whether the standard 
should include other options;
     Whether the standard should include any additional 
acclimatization requirements for employees returning after less than 14 
days away from work after acute illnesses that may put them at 
increased risk of heat-related illness (i.e., illnesses involving fever 
or gastrointestinal infections), and if so, suggestions and evidence 
for the additional requirements; and
     Considering that employees starting or returning when the 
heat index is above 90 [deg]F would not receive unique acclimatization 
benefits if the employer chose Option A, whether the standard should 
specify additional requirements for these scenarios, such as breaks 
that are more frequent or of longer duration.
    OSHA has concerns that the proposed exception in paragraph 
(e)(7)(iii) could create incentives for employees to lie and/or 
employers to pressure employees to lie about their acclimatization 
status. For example, an employer could pressure an employee to report 
that they consistently worked under the same or similar conditions 
within the prior 14 days, so that the employer does not need to comply 
with paragraph (e)(7) during the employee's first week on the job. 
These incentives could put new and returning employees at increased 
risk because they are not receiving appropriate protection based on 
their acclimatization status. OSHA seeks comments and evidence on the 
likelihood of this happening and what OSHA could do to address these 
potential troubling incentives.
VIII. Rest Breaks if Needed
    Proposed paragraph (e)(8) would require employers to allow and 
encourage employees to take paid rest breaks in break areas that would 
be required under paragraphs (e)(3) or (4) if needed to prevent 
overheating. As discussed in Section V.C., Risk Reduction, rest breaks 
have been shown to be an effective intervention for preventing HRI by 
allowing employees to reduce their work rate and body temperature. Rest 
breaks allow employees time to hydrate and cool down in areas that are 
shaded, air-conditioned, or cooled with other measures. Therefore, OSHA 
preliminary finds that allowing employees to take rest breaks when they 
are needed to prevent overheating is an important control for 
preventing or reducing HRIs in the workplace.
    Providing employees the opportunity to take unscheduled rest breaks 
to prevent overheating helps to account for protecting employees who 
vary in susceptibility to HRI and address scenarios where employees 
might experience increased heat strain. For example, unscheduled rest 
breaks may help to protect employees who are more susceptible to HRI 
for reasons such as chronic health conditions, recent recovery from 
illness, pregnancy, prior heat-related illness, or use of certain 
medications (see Section IV.O., Factors that Affect Risk for Heat-
Related Health Effects). Unscheduled rest breaks may also help reduce 
heat strain in employees who are assigned new job tasks that are more 
strenuous than the tasks they were performing. Additionally, rest 
breaks would allow employees an opportunity to remove any PPE that may 
be contributing to heat strain.
    Under proposed paragraph (e)(8), employees would be allowed to 
decide on the timing and frequency of unscheduled rest breaks to 
prevent overheating. However, unscheduled rest breaks must be heat-
related (i.e., only if needed to prevent overheating). In addition, if 
the work process is such that allowing employees to leave their work 
station at their election would present a hazard to the employee or 
others, or if it would result in harm to the employer's equipment or 
product, the employer could require the employee to notify a supervisor 
and wait to be relieved, provided a supervisor is immediately available 
and relieves the employee as quickly as possible.
    An example of a scenario where an employee may decide they need a 
rest break is if the employee experiences certain symptoms that 
suggests the employee is suffering from excessive heat strain but does 
not have an HRI that would need to be addressed under proposed 
paragraph (g)(2) (e.g., excessive thirst, excessive sweating, or a 
general feeling of unwellness that the employee attributes to heat 
exposure). However, rest breaks to prevent overheating do not need to 
be tied to onset of symptoms. For example, if an employee starts to 
have trouble performing a task on a hot day that they do not normally 
have trouble performing, that may be a sign they need a break. OSHA 
expects that most unscheduled rest breaks to prevent overheating would 
typically last less than 15 minutes. In some cases, a rest break that 
extends beyond 15 minutes or frequent unscheduled rest breaks may be a 
sign that the employee may be experiencing an HRI.
    As noted, proposed paragraph (e)(8) requires employers to both 
encourage and allow employees to take a paid rest break if needed. 
Employers can encourage employees to take rest breaks by periodically 
reminding them of that option. Although employers must allow employees 
to take breaks if the employee determines one is needed, nothing 
precludes an employer from asking or directing an employee to take an 
unscheduled paid rest break if the employer notices signs of excessive 
heat strain in an employee.
    Slowing the pace of work would not be considered a rest break, and 
as specified in proposed paragraph (e)(8), rest breaks if needed must 
be provided in break areas required under paragraph (e)(3) or (4) (see 
Explanation of Proposed Requirements for paragraphs (e)(3), Break 
area(s) at outdoor work sites and (e)(4), Break area(s) at indoor work 
sites for additional discussion of break areas and Explanation of 
Proposed Requirements for paragraph

[[Page 70787]]

(f)(2), Rest breaks, for additional discussion related to rest breaks.)
    Proposed paragraph (e)(8) would require that employees be paid 
during the time they take rest breaks needed to prevent overheating. 
OSHA preliminary finds it is important that these breaks be paid so 
that employees are not discouraged from taking them. The reason for 
requiring these breaks be paid is further explained in the Explanation 
of Proposed Requirements for paragraph (j), Requirements implemented at 
no cost to employees, including the importance of the requirement and 
how employers can ensure that employees are compensated to ensure they 
are not financially penalized for taking breaks that would be allowed 
or required under the proposed standard.
    Evidence indicates that employees are often reluctant to take 
breaks and thus, are not likely to abuse the right to take rest breaks 
if needed to prevent overheating; to the contrary, the evidence shows 
that employees are more likely to continue working when they should 
take a rest break to prevent overheating. A review of the evidence 
showing that many employees are reluctant to take rest breaks is 
included in the Explanation of Proposed Requirements for paragraph 
(f)(2) Rest breaks.
A. Requests for Comments
    OSHA seeks comments and information on the proposed requirement to 
provide employees with rest breaks if needed to prevent overheating, 
including:
     If there are specific signs or symptoms that indicate 
employees need a rest break to prevent overheating;
     If employers currently offer rest breaks if needed to 
prevent overheating, and if so, whether employees take rest breaks when 
needed to prevent overheating;
     The typical duration of needed rest breaks taken to 
prevent overheating; and
     Any challenges to providing rest breaks if needed to 
prevent overheating.
    In addition, OSHA encourages stakeholders to provide information 
and comments on the questions regarding compensation of employees 
during rest breaks in the Explanation of Proposed Requirements for 
paragraph (j), Requirements implemented at no cost to employees.
IX. Effective Communication
    Paragraph (e)(9) of the proposed standard establishes requirements 
for effective communication at the initial heat trigger. Early 
detection and treatment of heat-related illness is critical to 
preventing the development of potentially fatal heat-related 
conditions, such as heat stroke (see Section V., Health Effects). 
Effective two-way communication provides a mechanism for education and 
notification of heat-related hazards so that appropriate precautions 
can be taken. It also provides a way for employees to communicate with 
the employer about signs and symptoms of heat-related illness, as well 
as appropriate response measures (e.g., first aid, emergency response).
    The NACOSH Heat Injury and Illness Prevention Work Group 
recommended that elements of a proposed standard for prevention of HRIs 
address communication needs to meet the objective of monitoring the 
work site to accurately assess conditions and apply controls based on 
those conditions. The Work Group recommended addressing communications 
needs for tracking to facilitate monitoring and check-ins so that 
employees can report back to employers (NACOSH Working Group on Heat, 
2023).
    OSHA preliminarily finds that two-way, regular communication is a 
critical element of HRI prevention. Paragraph (e)(9) requires the 
employer maintain effective, two-way communication with employees and 
regularly communicate with employees. The means of communication must 
be effective. In some cases, voice (or hand signals) may be effective, 
but if that is not effective at a particular workplace (e.g., if 
employees are not close together and/or not near a supervisor), then 
electronic means may be needed to maintain effective communication 
(e.g., handheld transceiver, phone, or radio). If the employer is 
communicating with employees by electronic means, the employer must 
respond in a timely manner for communication to be effective (e.g., 
providing a phone number for employees to call would not be effective 
if no one answers or responds in a timely manner).
    The means of communication must also be ``two-way'' (i.e., a way 
for the employer to communicate with employees, and for employees to 
communicate with the employer). This is important because this provides 
a means for employees to reach the employer when someone is exhibiting 
the signs and symptoms of heat-related illness.
    Paragraph (e)(9) also requires that employers regularly communicate 
with employees. The employer could comply with this requirement by 
regularly reaching out to employees, or setting up a system by which 
employees are required to make contact, or check in, with the employer. 
However, it is the employer's responsibility to ensure that regular 
communication is maintained with employees (e.g., every few hours). If 
a system is chosen whereby the employer requires employees to initiate 
communication with the employer, and if the employer does not hear from 
the employee in a reasonable amount of time, the employer must reach 
out to the employee to ensure that they are not experiencing heat-
related illness symptoms. Employers must ensure that when it is 
necessary for an employee to leave a message (e.g., text) with the 
employer, the employer will respond, if necessary, in a reasonable 
amount of time.
    This proposed requirement also applies for employees who work alone 
on the work site. This means that the communication system chosen by 
the employer must allow for communication between these employees and 
the employer, although the means may be different than for employees 
who work on a work site with multiple employees (e.g., by electronic 
means).
A. Requests for Comments
    OSHA requests comments and evidence regarding the following:
     How employers currently communicate with employees working 
alone, including any challenges for effectively communicating with 
employees working alone and any situations where communication with 
employees working alone may not be feasible; and
     Whether OSHA should specify a specific time interval at 
which employers must communicate with employees and, if so, what the 
interval should be, and the basis for such a requirement.
X. Personal Protective Equipment (PPE)
    Paragraph (e)(10) of the proposed standard would require employers 
to maintain the cooling properties of cooling PPE if provided to 
employees. The proposed standard does not require employers to provide 
employees with cooling PPE. However, if employers do provide cooling 
PPE, they must ensure the PPE's cooling properties are maintained at 
all times during use. It is critical that employers who provide cooling 
PPE maintain the equipment's cooling properties; when these properties 
are not maintained, the defective equipment can heighten the risk of 
heat injury or illness with continued use. Reports from employees 
indicate that the use of cooling PPE, such as cooling vests, is 
burdensome and increases heat retention once the

[[Page 70788]]

cooling properties are lost or ice packs have melted (Chicas et al., 
2021).
A. Requests for Comments
    OSHA requests comments and evidence as to whether there are any 
scenarios in which wearing cooling PPE is warranted and feasible and 
OSHA should require its use.

F. Paragraph (f) Requirements at or Above the High Heat Trigger

I. Timing
    Paragraph (f) of the proposed standard would establish requirements 
when employees are exposed to heat at or above the high heat trigger. 
As discussed in Section V.B., Basis for Initial and High Heat Triggers, 
OSHA has preliminarily determined that the experimental and 
observational evidence support that heat index triggers of 80 [deg]F 
and 90 [deg]F are highly sensitive and therefore highly protective of 
employees. Exposures at or above the high heat trigger, a heat index of 
90 [deg]F, or a corresponding wet bulb globe temperature equal to the 
NIOSH Recommended Exposure Limit, would require the employer to provide 
the protections outlined in paragraphs (f)(2) through (5). These 
protections would be in addition to the measures required by paragraph 
(e) Requirements at or above the initial heat trigger, which remain in 
effect after the high heat trigger is met.
    The employer would only be required to provide the protections 
specified in paragraph (f) during the time period when employees are 
exposed to heat at or above the high heat trigger. In many cases, 
employees may only be exposed at or above the high heat trigger for 
part of their work shift. For example, employees may begin work at 9 
a.m. and finish work at 5 p.m. If their exposure is below the high heat 
trigger from 9 a.m. until 2 p.m., and at or above the high heat trigger 
from 2 p.m. to 5 p.m., the employer would only be required to provide 
the protections specified in this paragraph from 2 p.m. to 5 p.m. 
Protective measures outlined in paragraph (e) Requirements at or above 
the initial heat trigger, would be required at any time when employees 
are exposed to heat at or above the initial heat trigger.
II. Rest Breaks
    Proposed paragraph (f)(2) specifies the minimum frequency and 
duration for rest breaks that would be required (i.e., 15 minutes every 
two hours) when the high heat trigger is met or exceeded and provides 
clarification on requirements for those rest breaks.
A. Background on the Provision
    As discussed in Section V.C., Risk Reduction, rest breaks have been 
shown to be an effective intervention for preventing HRI by allowing 
employees to reduce their work rate and body temperature. Rest breaks 
also allow employees time to hydrate and cool down in areas that are 
shaded, air-conditioned, or cooled with other measures. OSHA 
preliminarily finds there are at least two reasons that warrant the 
inclusion of rest breaks at a minimum frequency and duration when the 
high heat trigger is met or exceeded. The first is that heat strain is 
greater in employees exposed to higher levels of heat. (See Section 
IV., Health Effects).
    The second is that the available evidence shows many employees are 
not taking adequate or enough rest breaks. This evidence shows that 
while workers paid on a piece-rate basis (e.g., compensated based on 
factors such as quantity of produce picked, jobs completed, or products 
produced) may be especially reluctant to take breaks because of 
financial concerns (Lam et al., 2013; Mizelle et al., 2022; Iglesias-
Rios et al., 2023; Spector et al., 2015; Wadsworth et al., 2019), a 
significant portion of employees paid on an hourly basis are also not 
taking adequate breaks for other reasons such as pressure from co-
workers or supervisors, high work demands, or attitudes related to work 
ethics (Arnold et al., 2020; Wadsworth et al., 2019). For example, 
Langer et al. (2021) surveyed 507 Latinx California farmworkers (77% 
paid hourly) during the summers of 2014 and 2015, when California 
regulations to protect employees from heat required employers to 
provide rest breaks if needed but did not require rest breaks at a 
minimum frequency and duration; 39% of surveyed employees reported 
taking fewer than 2 rest breaks (not including lunch) per day. 
Additionally, in a study of 165 legally employed child Latinx farm 
employees (64% hourly workers) ranging in age from 10-17 years in North 
Carolina, 88% reported taking breaks in shade, but based on some 
interviews, the breaks appeared to be of short duration (e.g., ``for 
some five minutes;'' ``you can take a break whenever you want . . . not 
for a long time . . . if you wanna get a drink of water only for a 
couple of minutes, three or five'') (Arnold et al., 2020). The children 
who were interviewed by Arnold et al. (2020) reported pressure to keep 
up with the pace of work and being discouraged to take breaks by co-
workers or supervisors. In interviews of 405 migrant farmworkers in 
Georgia, 20% reported taking breaks in the shade (Fleischer et al., 
2013).
    In a study of 101 farmworkers (61% paid hourly) in the Florida/
Georgia region, Luque et al. (2020) reported that only 23% took breaks 
in the shade. The need for breaks was supported by observations that 
while some employees carried water bottles, most were only seen 
drinking during rest breaks. In another study, focus group discussions 
with piece-rate farm employees revealed that many expressed concerns 
about possible losses in earnings and that they might be replaced by 
another employee if they took breaks. Many such employees brought their 
own water to work to reduce the time they are not picking produce 
(Wadsworth et al., 2019). In that same study by Wadsworth et al. 
(2019), piece rate farmworkers also described ``their desire to be seen 
as a good worker, with great fortitude.'' Good workers were described 
by the farmworkers as those who ``work fast and do not slow things down 
and jeopardize success for the group. They continue working in spite of 
the conditions or how they feel.'' (Wadsworth et al., 2019, p. 224). A 
case study highlighted in the NIOSH criteria document discusses a 
migrant farmworker who died from HRI after he continued to work despite 
a supervisor instructing him to take a break because he was working 
slowly (NIOSH 2016, pp. 46-47). On the day of his death, the heat index 
ranged from 86 to 112 [deg]F.
    Evidence supporting the need for required rest breaks is not 
limited to farmworkers. For example, a NIOSH health hazard evaluation 
(HHE) indicated that truck drivers for an airline catering facility 
often skipped breaks they were allowed to take between deliveries in an 
air-conditioned room at the catering facility to keep up with job 
demands (NIOSH, 2016, p. 44). Such attitudes appear common in employees 
of all sectors. Phan and Beck (2023) surveyed 107 office workers, and 
25-33% of those employees reported they skipped breaks because of a 
high workload, not wanting to lose momentum, or to reduce the amount of 
work to be completed in the future. A number of informal surveys 
reported similar findings for office and remote workers. In those 
surveys, many employees (approximately 40%) skip some breaks, 
particularly lunch breaks (Tork, June 14, 2021; Joblist, July 5, 2022). 
Common reasons for skipping lunch breaks included work demands and 
feelings of guilt or being judged for taking a break (Tork, June 14, 
2021; Joblist, July 5, 2022). One survey also reported that a major 
reason why many employees do not take paid time off is

[[Page 70789]]

because of concerns for coworkers (Joblist, July 5, 2022). Although 
these informal surveys cover employees who would likely not be covered 
by the scope of this proposed standard, these informal surveys echo the 
findings of the studies in the preceding paragraphs and show that 
employees generally do not take rest breaks or other paid time off.
    Studies of presenteeism (i.e., working while ill or injured) 
suggest that employees may be more likely to ignore signs of excessive 
heat strain than they are to take breaks needed to prevent overheating. 
Hemp (October 2004, pp. 3-4) stated ``[u]nderlying the research of 
presenteeism is the assumption that employees do not take their jobs 
lightly, that most of them need and want to continue working if they 
can.'' Although financial reasons such as lack of paid leave are often 
drivers of presenteeism, non-financial considerations also play a major 
role. One study analyzed presenteeism in many of the industries covered 
by the proposed standard including in the categories of agriculture, 
utilities, manufacturing, transportation and storage, and construction 
(Marklund et al., 2021). Non-financially related reasons for 
presenteeism reported by Marklund et al. (2021) were not wanting to 
burden coworkers, perception that no one else can do the work, 
enjoyment of work, not wanting to be perceived as lazy or unproductive, 
and pride. Similar reasons were reported in other studies including 
wanting to spare co-workers from additional work, pressure from 
coworkers, strong teamwork and good relationships with coworkers, 
examples set by management, institutional loyalty, or a perception that 
taking time off is underperformance (Garrow, February 2016; Lohaus et 
al., 2022).
    The proposed requirement to include mandatory rest breaks is 
consistent with recommendations by authoritative sources. For example, 
NIOSH recommends mandatory rest breaks (NIOSH, 2016, p. 45; NIOSH, 
2017b, p.1). Additionally, ACGIH (2023) lists ``appropriate breaks with 
shade'' as an essential element of a heat stress management program. 
The NACOSH Working Group on Heat also recommended that scheduled, 
mandatory rest breaks be provided without retaliation (NACOSH Working 
Group on Heat, 2023, pp. 6-7).
    OSHA examined a number of studies to determine an appropriate 
frequency and duration of rest breaks. First, a series of laboratory 
studies by Notley et al. (2021; 2022a, b) provide insight on the 
appropriate frequency of rest breaks. In those studies, unacclimatized 
participants wearing a single clothing layer exercised at a moderate 
intensity level until stay time was reached (i.e., core temperatures 
reached 38 [deg]C (100.4 [deg]F) or increased by at least 1 [deg]C) at 
various ambient temperatures and at a relative humidity of 35% (Notley 
et al., 2021; 2022a, b).\1\ In a study of younger (18-30 years old) and 
older men (50-70 years old), data from all participants were pooled to 
calculate initial stay times of 111 minutes at ambient conditions of 
34.1 [deg]C (93.4 [deg]F) (heat index = 93.9 [deg]F) and 44 minutes at 
ambient conditions of 41.4 [deg]C (106.5 [deg]F) (heat index = 119.8 
[deg]F) (Notley et al., 2022b). In a study of unacclimatized younger 
men (mean age 22 years), older men (mean age 58 years), and older men 
with diabetes (mean age 60 years) or hypertension (mean age 61 years), 
median stay times were 128 minutes at 36.6 [deg]C (97.9 [deg]F) (heat 
index = 101.5 [deg]F) and 68 minutes at 41.1 [deg]C (106.5 [deg]F) 
(heat index = 118.5 [deg]F) (Notley et al., 2021). In a third study, 
unacclimatized men and women were able to work for a median time of 117 
minutes at 36.6 [deg]C (97.9 [deg]F) (heat index = 101.5 [deg]F) and 63 
minutes at 41.4 [deg]C (106.5 [deg]F) (heat index = 119.8 [deg]F) 
(Notley et al., 2022a). Overall, the results of these studies support 
work times ranging from 111 minutes to 128 minutes at heat indices of 
93.9 [deg]F to 101.5 [deg]F and 44 to 68 minutes at heat indices of 
118.5 [deg]F to 119.8 [deg]F.
    Two laboratory studies support a preliminary conclusion that rest 
breaks contribute to the protection of workers from the effects of heat 
(Uchiyama et al., 2022; Smallcombe et al., 2022). These studies were 
conducted over periods that could represent all or part of a workday, 
with light exertion exercise conducted under hot conditions (e.g., 37 
;C (98.6 [deg]F) and 40% relative humidity (heat index = 106 [deg]F)) 
in Uchiyama et al. (2022), and moderate to heavy exertion exercise 
conducted under four conditions: 15 [deg]C (59 [deg]F) and 50% relative 
humidity (referent group, heat index not relevant), 35 [deg]C (95 
[deg]F) 50% relative humidity (heat index = 105 [deg]F); 40[deg]C (104 
[deg]F) and 50% relative humidity (heat index = 131 [deg]F); and 40 
[deg]C (104 [deg]F), and 70% relative humidity (heat index=161 [deg]F) 
in Smallcombe et al. (2022). In both studies, breaks were provided in 
air-conditioned or cooler areas. The studies show little evidence of 
excessive heat strain in participants as mean core temperatures 
remained within 1 [deg]C of 37.5 [deg]C (99.5 [deg]C) (ACGIH, 2023, p. 
244). Uchiyama et al. (2022) evaluated two work/rest protocols, 
including one in which participants exercised for 1 hour, rested for 30 
minutes, exercised for 1 hour, rested for 15 minutes, and then 
exercised for another hour; increases in mean core temperatures were 
less than 1 [deg]C above mean baseline temperature (37.2 [deg]C) in 
five of the six time points reported and slightly exceeded a 1 [deg]C 
increase at 180 minutes, the final time point of measurement (38.29 
[deg]C). OSHA finds these work/rest cycles to be similar to a late 
morning period of work, followed by a 30-minute lunch and then an early 
afternoon work/rest period, although acknowledges that the duration 
between rest periods is longer in the proposed rule than in this study. 
Also, in the Uchiyama et al. (2022) study, a lack of heat strain was 
also observed in a protocol consisting of 1 hour of work and 15 minutes 
rest, followed by three half hour work periods separated by 10-minute 
rest periods and, and a final half hour work period.
    The Smallcombe et al. (2022) study most closely reflected a typical 
workday because it was conducted over a 7-hour period with cycles of 
50-minute work/10-minute rest and a 1-hour lunch. Participants were 
tested under one referent conditions and three hot temperature 
conditions and average rectal temperature remained at or below 38 
[deg]C (100.4 [deg]F) in all groups during each exercise period at heat 
indices ranging from 105 [deg]F to 161 [deg]F (table S2).
    Overall, OSHA preliminarily finds that these studies show that 15-
minute rest breaks would offer more protection for employees than 
shorter duration rest breaks, because the frequency of rest breaks in 
these studies by Uchiyama et al. (2022) and Smallcombe et al. (2022) 
was greater than what OSHA is proposing and rest breaks were provided 
in air-conditioned or cooler areas. OSHA expects some employees will 
not have access to air-conditioned areas during break periods. OSHA 
acknowledges uncertainties in determining a precise rest break 
frequency and duration, but preliminarily concludes that a minimum of a 
15-minute rest break every two hours would be highly protective in many 
circumstances at or above the high heat trigger, while offering 
employers administrative convenience. For example, other approaches 
such as adjusting rest break frequency and duration based on weather 
conditions, work intensity, or protective clothing are likely to be 
difficult for many employers to implement. A 15-minute break every two 
hours is administratively convenient to implement because, as explained 
below, a standard meal break could qualify as a rest break, and

[[Page 70790]]

therefore, assuming an 8-hour workday with a meal break in the middle 
of the day, paragraph (f)(2) would only require two other breaks, one 
break in the morning and a second break in the afternoon, assuming the 
high heat trigger is met or exceeded the entire day.
    The frequency and duration of these proposed rest breaks are within 
the ranges of frequencies and durations required by four U.S. States 
that have finalized regulations protecting against HRI by requiring 
rest breaks under high heat conditions. First, the California 
regulation for outdoor employees requires a minimum ten-minute rest 
period every two hours for agricultural employees, when temperatures 
reach or exceed 95 [deg]F (Cal. Code Regs. tit. 8, section 3395 
(2024)). Second and similarly, the Colorado regulation for agricultural 
employees requires a minimum 10-minute rest period every two hours 
under increased risk conditions that include a temperature at or above 
95 [deg]F (7 Colo. Code Regs. section 1103-15:3 (2023)). Third, in 
Oregon rules applying to agriculture as well as indoor and outdoor 
workplaces, employers can select from three different options for work-
rest periods at high heat, including: (1) an employer-designed program 
with a minimum of a 10-minute break every two hours at a heat index of 
90 [deg]F or greater and a 15-minute break every hour at a heat index 
of 100 [deg]F or greater, with possible increased frequency and 
duration of breaks based on PPE use, clothing, relative humidity, and 
work intensity; (2) development of work/rest schedules based on the 
approach recommended by NIOSH (see NIOSH, 2016), or (3) a simplified 
rest break schedule that calls for a 10-minute break every two hours, 
with durations and frequencies of rest breaks increasing with increases 
in heat index (Or. Admin. R. 437-002-0156 (2024); Or. Admin. R. 437-
004-1131 (2024)). Fourth and finally, for outdoor workplaces, 
Washington requires a minimum 10-minute rest period every two hours at 
an air temperature at or above 90 [deg]F and a minimum 15-minute rest 
period every hour at an air temperature at or above 100 [deg]F (Wash. 
Admin. Code 296-307-09747 (2023)).
    A NIOSH guidance document recommends work/rest cycles for employees 
wearing ``normal clothing'' that considers temperature adjusted for 
humidity levels and cloud cover and work intensity; in that guidance, 
when the need for rest cycles is triggered, work/rest cycles range from 
45 minutes work/15 minutes rest to 15 minutes work/45 minutes rest, 
with extreme cautioned urged under some conditions (NIOSH, 2017b).
    OSHA acknowledges the requirements of some States and 
recommendations by NIOSH to increase frequency and duration of rest 
breaks as heat conditions increase, but OSHA has preliminarily decided 
on a more simplified approach, in part because of implementation 
concerns raised by stakeholders, such as difficulty in implementing a 
more complex approach (e.g., longer and more frequent rest breaks with 
increasing temperature), and interference with certain types of work 
tasks (e.g., continuous production work and tasks such as pouring 
concrete that could be disrupted by more frequent breaks). In addition, 
the requirement to continue providing paid breaks if needed above the 
high heat trigger, coupled with the requirement to encourage employees 
to take these breaks, will help ensure that any employee that needs an 
additional break can take one. However, OSHA acknowledges that, for the 
reasons discussed above, this encouragement may become more vital as 
the temperature increases to ensure that employees don't forego the 
breaks they are entitled to. OSHA welcomes comment and data on the 
appropriateness of this approach.
B. Complying With Rest Break Provisions
    The required break periods under paragraph (f)(2) are a minimum. 
Nothing in the proposed standard would preclude employers from 
providing longer or more frequent breaks. Additionally, employers would 
need to comply with paragraph (e)(8) (i.e., providing rest breaks if 
needed to prevent overheating), which may include situations where 
employees need more frequent or longer break periods. Paragraph (f)(2) 
requires employers to ensure that employees have at least one break 
that lasts a minimum of 15 minutes every two hours when the high heat 
trigger is met or exceeded. The requirement is in addition to 
employers' obligation under paragraph (e)(8) to allow and encourage 
rest breaks if needed to prevent overheating, which continues after the 
high heat trigger is met. However, if an employee takes a rest break 
under paragraph (e)(8) that lasts at least 15 consecutive minutes, that 
would impact when the employer would next need to provide a break under 
paragraph (f)(2). For example, if the high heat trigger is exceeded for 
an entire 8-hour work day, and the employee takes a 15-minute break 
after their first hour of work because they need one to prevent 
overheating, the employer would not be required to provide another 15-
minute break under paragraph (f)(2) for the next two hours. However, 
the employer's on-going obligation under paragraph (e)(8) would remain. 
Employers would also need to comply with paragraph (g)(2) (i.e., 
relieving an employee from duty when they are experiencing signs and 
symptoms of heat-related illness).
    Under proposed paragraph (f)(2), when the high heat trigger is met 
or exceeded, employers would be required to provide a minimum 15-minute 
paid rest break at least every two hours in the break area that would 
be required under paragraph (e)(3) or (4). These rest breaks would be 
mandatory, and the employer would need to ensure that rest breaks are 
taken as required.
    Proposed paragraphs (f)(2) and (e)(8) would require that employees 
be paid during rest breaks. As discussed further in the Explanation of 
Proposed Requirements for paragraph (j), Requirements implemented at no 
cost to employees, OSHA finds it important that employees be paid 
during the time they are taking breaks that are mandatory or needed to 
prevent overheating so that employees are not financially penalized and 
thus discouraged from taking advantage of those protections. See 
Explanation of Proposed Requirements for paragraph (j) for Requirements 
implemented at no cost to employees for a discussion of approaches 
employers can take to ensure that both hourly employees and piece rate 
employees are compensated for time on rest breaks.
    Rest breaks are not the same as slowing down or pacing. In 
addition, performing a sedentary work activity, even if done in an area 
that meets the requirements of a break area under proposed paragraphs 
(e)(3) or (4), would not be considered a rest break under the proposed 
standard. This ensures that employees can rest (thus modulating 
increases in heat strain) and hydrate during that rest break.
    OSHA recognizes that providing a rest break every two hours might 
be challenging for some employers. However, employers could consider 
approaches such as staggering employee break times, within the required 
two-hour period, to ensure that some employees are always available to 
continue working. In other cases, employers who have concerns about 
employee safety, such as having to climb up and down from high 
locations to take a break, might be able to provide portable shade 
structures, if safe to use under the conditions (e.g., elevation, wind 
conditions). In addition, employers could consider scheduling work 
tasks during cooler parts of the day to avoid required rest breaks.

[[Page 70791]]

    Proposed paragraphs (f)(2)(i) indicates that a meal break that is 
not required to be paid under law may count as a rest break. Whether a 
meal break must be paid is governed by other laws, including State 
laws. Under the Federal Fair Labor Standards Act, bona fide meal 
periods (typically 30 minutes or more) generally do not need to be 
compensated as work time (see 29 CFR 785.19). The employee must be 
completely relieved from duties for the purpose of eating regular 
meals. Furthermore, an employee is not relieved if they are required to 
perform any duties, whether active or inactive, while eating.
    Proposed paragraphs (f)(2)(ii) and (iii) further clarify that total 
time of the rest break would not include the time that employees take 
to put on and remove PPE or the time to walk to and from the break 
area. OSHA preliminarily finds it important to exclude this time from 
the 15-minute rest period so employees have the full 15 minutes to cool 
down.
C. Requests for Comments
    OSHA requests comments and evidence regarding the following:
     Stakeholders' experiences with rest breaks required under 
law or by the employer, including successes and challenges with such 
approaches;
     Whether there is additional evidence to support a 15-
minute rest break every 2 hours as effective in reducing heat strain 
and preventing HRIs;
     Whether OSHA should consider an alternative scheme for the 
frequency and/or duration of rest breaks under paragraph (f)(2). If so, 
what factors (such as weather conditions, intensity of work tasks, or 
types of clothing/PPE) should it be based on and why;
     Whether varying frequency and duration of rest breaks 
based on factors such as the heat index would be administratively 
difficult for employers to implement and how any potential 
administrative concerns could be addressed;
     Whether employees could perform certain sedentary work 
activities in areas that meet the proposed requirements for break areas 
without hindering the effectiveness of rest breaks for preventing HRI, 
including examples of activities that would or would not be acceptable; 
and
     Whether OSHA should require removal of PPE that may impair 
cooling during rest breaks.
III. Observation for Signs and Symptoms
    Paragraph (f)(3) of the proposed standard would establish 
requirements for observing employees for signs and symptoms of heat-
related illness when the high heat trigger is met or exceeded. As 
explained in Section IV., Health Effects, heat-related illnesses can 
progress to life-threatening conditions if not treated properly and 
promptly. Therefore, it is important to identify the signs and symptoms 
of heat-related illness early so appropriate action can be taken to 
prevent the condition from worsening. OSHA preliminarily finds that 
observation for signs and symptoms of heat-related illness in employees 
is a critical component of heat injury and illness prevention.
    NIOSH recommends observation for signs and symptoms of heat-related 
illness by a fellow worker or supervisor (NIOSH, 2016). The NACOSH Heat 
Injury and Illness Prevention Work Group also provided recommendations 
related to observation for signs and symptoms of heat-related illness 
in its recommendations to OSHA on potential elements of heat injury and 
illness prevention standard. The NACOSH Work Group recommended that 
there be additional requirements for workers who work alone since a 
buddy system is not possible in those cases, including a communication 
system with regular check-ins (NACOSH Working Group on Heat, 2023).
    Paragraph (f)(3) would require that the employer implement at least 
one of two methods of observing employees for signs and symptoms of 
heat-related illness, with a third option for employees who work alone 
at a work site. As defined under proposed paragraph (b), Signs and 
symptoms of heat related illness means the physiological manifestations 
of a heat-related illness and includes headache, nausea, weakness, 
dizziness, elevated body temperature, muscle cramps, and muscle pain or 
spasms.
    The first option, under proposed paragraph (f)(3)(i), that an 
employer may choose is to implement a mandatory buddy system in which 
co-workers observe each other. Employers could satisfy this requirement 
by pairing employees as ``buddies'' to observe each other for signs and 
symptoms of heat-related illness. Co-workers assigned as buddies would 
need to be in the same work area so that it is possible for them to 
observe each other. Co-workers could also use visual cues or signs and/
or verbal communication to communicate signs and symptoms of heat-
related illness to each other.
    The second option, under proposed paragraph (f)(3)(ii), that the 
employer may choose is for observation to be carried out by a 
supervisor or heat safety coordinator. If the employer chooses this 
option, proposed paragraph (f)(3)(ii) specifies that no more than 20 
employees can be observed per supervisor or heat safety coordinator. 
OSHA preliminarily finds that it is important to limit the number of 
employees being observed to ensure that each employee is receiving the 
amount of observation needed to determine if they are experiencing any 
signs and symptoms of heat-related illness. Supervisors or heat safety 
coordinators would need to be in a position to observe the employees 
they are responsible for observing for signs and symptoms (e.g., in 
close enough proximity to communicate with and see) when observing for 
signs/symptoms. The supervisor or heat safety coordinator could have 
other tasks or work responsibilities while implementing the observation 
role, but they must be able to be within close enough proximity to 
communicate with and see those they are observing and be able to check 
in with the employee regularly (e.g., every two hours). When the high 
heat trigger is met, employers would still be responsible for meeting 
the proposed requirements of paragraph (e)(9), Effective Communication. 
Employees need to have a means of effective communication with a 
supervisor (e.g., phone, radio) and employers must regularly 
communicate with employees at or above both the initial and high heat 
triggers.
    Because symptoms of heat-related illness may not be outwardly 
visible (e.g., nausea, headache), employers should ensure employees are 
asked if they are experiencing any signs and symptoms. This is 
especially true if the employee shows changes in behavior such as 
working more slowly or dropping things because this could indicate that 
the employee is experiencing heat-related illness but not recognizing 
it. It is also important that employees report any signs and symptoms 
they are experiencing or that they observe in others in order to 
prevent development of potentially life-threatening forms of heat-
related illness (see proposed paragraph (h)(1)(x), Training). 
Additionally, as discussed below, certain signs and symptoms indicate a 
heat-related emergency.
    Employees who work alone at a work site do not have a co-worker, 
supervisor, or heat safety coordinator present who can observe them to 
determine if they are experiencing signs and symptoms of heat-related 
illness. For employees working alone at a work site, the employer would 
instead need to comply with proposed paragraph (f)(3)(iii) and maintain 
a means of effective, two-way communication with those employees and 
make contact with them at least

[[Page 70792]]

every two hours. This means that employers must not only reach out to 
lone employees, but also receive a communication back from the 
employees. Receiving communication back from the employee allows the 
employee to report any symptoms. If no communication is received, this 
may be a sign that the employee is having a problem.
    Under proposed paragraph (h)(1)(iv), employers would be required to 
train employees on signs and symptoms of heat-related illness and which 
ones require immediate emergency action. Proposed paragraph (b) defines 
signs and symptoms of a heat emergency as physiological manifestations 
of a heat-related illness that requires emergency response and includes 
loss of consciousness (i.e., fainting, collapse) with excessive body 
temperature, which may or may not be accompanied by vertigo, nausea, 
headache, cerebral dysfunction, or bizarre behavior. This could also 
include staggering, vomiting, acting irrationally or disoriented, 
having convulsions, and (even after resting) having an elevated heart 
rate. Employer obligations when an employee is experiencing signs and 
symptoms of a heat-related illness or heat emergency are addressed 
under proposed paragraph (g).
A. Requests for Comments
    OSHA requests comments and evidence regarding the following:
     Stakeholders' experiences with implementing observational 
systems such as those that OSHA is proposing and examples of the 
implementation of other observational systems for signs and symptoms of 
heat-related illness that OSHA should consider;
     Data of the effectiveness of such observation systems;
     The frequency at which observation as described in this 
section should occur;
     Whether there are alternative definitions of signs and 
symptoms of heat-related illness that OSHA should consider;
     Whether employers should be able to select a designee to 
implement observation in situations where it may not be possible to 
have a supervisor or heat safety coordinator present;
     Possible logistical concerns regarding proposed 
requirements for communication at least every two hours for employees 
who work alone at the work site; whether there are examples of 
successful implementation of these types of communication systems; 
examples of the types of technologies or modes of communication that 
most effectively support this type communication; and whether there are 
innovative approaches for keeping employees working alone safe from HRI 
and allowing for prompt response in an emergency; and
     For employees who work alone at the work site, whether the 
employer should know the location of the employee at all times.
IV. Hazard Alert
    Paragraph (f)(4) of the proposed standard would require employers 
to issue a hazard alert to employees prior to a work shift or when 
employees are exposed to heat at or above the high heat trigger.
    As explained in Section IV., Health Effects, hazardous heat can 
lead to sudden and traumatic injuries and heat-related illnesses can 
quickly progress to life threatening forms if not treated properly and 
promptly. To protect employees, it is not sufficient to respond to HRIs 
after they occur. Prevention of HRIs is critical. A hazard alert will 
help prevent HRIs by notifying employees of heat hazards, providing 
information on HRI prevention, empowering employees to utilize 
preventative measures, and providing practical information about how to 
access prevention resources (e.g., drinking water, break areas to cool 
down) and seek help in case of emergency.
    Heat alert programs have been identified as important prevention 
strategies (NIOSH, 2016; Khogali, 1997). NIOSH identified heat alert 
programs as a strategy to prevent excessive heat stress and recommended 
that heat alert programs be implemented under certain high heat 
conditions (NIOSH, 2016, p. 10). NIOSH further describes an example of 
an effective heat alert program, drawing in part on recommendations 
described by Dukes-Dobos (1981). Effective elements of a hazard alert 
program include similar elements to the proposed provision (f)(4), such 
as ``Establish[ing] criteria for the declaration of a heat alert'' and 
``Procedures to be followed during the state of [the] [h]eat [a]lert'' 
(e.g., reminding employees to drink water) (NIOSH, 2016, pp. 80-81).
    Employees may face pressure or incentives to work through hazardous 
heat which can increase their risk of heat-related illness; some 
employees also may not recognize that they are developing signs and 
symptoms of a heat-related illness (see Section IV., Health Effects). 
The hazard alert provision would require that employers provide 
information about prevention measures, including employees' right to 
take rest breaks if needed, at the employees' election, and the rest 
breaks required by paragraph (f)(2), which will empower employees to 
utilize the preventative measures available. This requirement would 
also enable effective response in the event of a heat emergency by 
requiring employers to remind employees in advance of its heat 
emergency procedures.
    OSHA preliminarily finds that the hazard alert requirement in 
proposed paragraph (f)(4) is an important strategy for the prevention 
of HRIs. The provision includes minimum requirements for the hazard 
alert and provides flexibility for employers in how they implement the 
provision. Additionally, employers may choose to include additional 
information in the alert that is appropriate for their work sites.
    Paragraph (f)(4) would require that prior to the work shift or upon 
determining the high heat trigger is met or exceeded, the employer must 
notify employees of specific information relevant to the prevention of 
heat hazards. Specifically, the employer would be required to notify 
employees of the following: the importance of drinking plenty of water; 
employees' right to, at employees' election, take rest breaks if needed 
and the rest breaks required by paragraph (f)(2); how to seek help and 
the procedures to take in a heat emergency; and for mobile work sites, 
information on the location of break area(s) required by paragraph 
(e)(3) or (4) and drinking water required by paragraph (e)(2). Because 
the location of break area(s) and drinking water may change frequently 
for mobile work sites, it is important to make sure employees at those 
work sites are reminded of their location on high heat days. Mobile 
work sites include work sites that change as projects progress or when 
employees relocate to a new project (e.g., landscaping, construction).
    Paragraph (f)(4) would require the employer to issue the hazard 
alert prior to the work shift or upon determining the high heat trigger 
is met or exceeded. However, issuing the alert prior to the start of 
the work shift would not be required unless exposures will be at or 
above the high heat trigger at the start of the work shift. If the 
start of the work shift is below the high heat trigger and the hazard 
alert is not issued at the start of the work shift, then the hazard 
alert must be issued when the high heat trigger is met and ideally 
before exposure occurs. For example, if a work shift runs from 8 a.m. 
to 5 p.m. and the high heat trigger is not met until 10 a.m., the 
employer must either issue the alert at the beginning of the work 
shift, or issue the alert when the high heat

[[Page 70793]]

trigger is met at 10 a.m. If an employer regularly communicates with an 
employee via a particular means of communication and uses that form of 
communication to issue the alert, then the employer can presume the 
notification was received. If, however, the employer has reason to 
believe the hazard alert was not received, they would need to take 
additional steps to confirm.
    Employers could satisfy the requirements of this provision by 
posting signs with the required information at locations readily 
accessible and visible to employees. For example, some employers may 
choose to post signs at the entrance to the work site. Signs are not an 
option for all employers as they may not be sufficient to ensure 
employees receive the hazard alert (e.g., employers with mobile 
employees or employees who work alone on a work site). Additionally, 
signs may not be an option for employers who choose not to provide the 
hazard alert at the start of the work shift. For example, posting a 
sign at the entrance to the work site would not be sufficient to ensure 
employees are notified after all employees have already entered the 
work site. Employers may also satisfy the hazard alert notification 
requirement by issuing the alert electronically (e.g., via email, text 
message) or through verbal means (e.g., an in-person meeting, radio or 
voicemail). Employers may be able to use the system they have in place 
to meet the requirements of paragraph (e)(9) for effective, two-way 
communication with employees to issue the hazard alert.
    For any method the employer chooses to issue the hazard alert 
notification, the hazard alert must be sufficient to ensure all 
employees are notified of the information in paragraphs (f)(2)(i) 
through (iv). To ensure this, the hazard alert must be issued in 
languages and at a literacy level understood by employees.
A. Requests for Comments
    OSHA requests comments and evidence regarding the following:
     Whether any additional information should be required in 
the hazard alert;
     The frequency of the hazard alert, particularly in 
locations that frequently exceed the high heat trigger; and
     Any alternatives to a hazard alert requirement that OSHA 
should consider.
V. Excessively High Heat Areas
    Paragraph (f)(5) of the proposed standard would require that 
employers place warning signs at indoor work areas with ambient 
temperatures that regularly exceed 120 [deg]F. The warning signs must 
be legible, visible, and understandable to employees entering the work 
area. Specifying the requirement for warning signs ensures that all 
employees and contractors at the work site are aware of areas with 
excessively high heat. Warning signs signal a hazardous situation that, 
if not avoided, could result in death or serious injury and, if 
employees need to enter the areas, serve as a reminder to take 
appropriate precautions.
    The warning signs must be legible, visible, and understandable to 
employees entering the work areas. The sign must be in a location that 
employees can clearly see before they enter the excessively high heat 
area. To maintain visibility of the warning signs, employers must 
ensure that there is adequate lighting in the area to read the signs 
and that the signs are not blocked by items that would prevent 
employees from seeing them. The signs would have to be legible (e.g., 
writing or print that can be read easily). The proposed standard does 
not specify contents of the sign, but signs could include a signal word 
such as ``Danger'', the hazard (e.g., ``High Heat Area''), possible 
health effects (e.g., May Cause Heat-Related Illness or Death), 
information pertaining to who is permitted to access the area (e.g., 
Authorized Personnel Only), and what precautions entrants would have to 
take to safely enter the area. Employees must be able to understand the 
signs. Therefore, the signs must be printed in a language or languages 
that all potentially exposed employees understand. If it is not 
practical to provide signs in a language or languages spoken by all 
employees, employers still must ensure all employees understand what 
the signs mean. Employers could do this by training on what the warning 
signs mean and providing those employees with information regarding the 
extent of the hazardous area as indicated on the signs.
    Employers would have to place warning signs at indoor work areas 
with ambient temperatures that regularly exceed 120 [deg]F. The term 
``regularly'' means a pattern or frequency of occurrence rather than 
isolated incidents. This would mean that the indoor work areas 
experience temperatures exceeding 120 [deg]F on a frequent or recurring 
basis, such as daily during certain seasons or under specific 
operational conditions. The process of identifying heat hazards 
pursuant to proposed paragraph (d) may help employers identify 
excessively high heat areas. Under proposed paragraph (d)(3), employers 
would be required to identify each work area(s) where employees are 
reasonably expected to be exposed to heat at or above the initial heat 
trigger and develop a monitoring plan. If, while monitoring, an 
employer determines temperatures in an indoor work area regularly 
exceed the 120 [deg]F threshold, then the employer would need to ensure 
that warning signs are placed at that work area to alert employees to 
the potential hazards associated with such extreme temperatures.
    If an employer's work site contains an excessively high heat 
area(s), the employer must train employees in the procedures to follow 
when working in these areas (see proposed provision (h)(1)(xvi)).
A. Requests for Comments
    OSHA requests comments and evidence regarding the following:
     Whether OSHA should further specify the required location 
of warning signs;
     Whether OSHA should specify the wording/contents of the 
warning signs; and
     Whether OSHA should consider defining ``excessively high 
heat area'' as something other than a work area in which ambient 
temperatures regularly exceed 120 [deg]F; and evidence available to 
support a different temperature threshold or other defining criteria.

G. Paragraph (g) Heat Illness and Emergency Response and Planning

    Paragraph (g) of the proposed standard would establish requirements 
for heat illness and emergency response and planning. It would require 
that employers develop and implement a heat emergency response plan as 
part of their HIIPP, as well as specify what an employer's 
responsibilities would be if an employee experiences signs and symptoms 
of heat-related illness or a heat emergency. Effective planning and 
emergency response measures can minimize the severity of heat-related 
illnesses when they occur and allow for more efficient access to 
medical care when needed.
    Proposed paragraph (g)(1) specifies that the employer would be 
required to develop and implement a heat emergency response plan as 
part of their HIIPP and specifies the elements that would be required 
in an employer's emergency response plan. Because the emergency 
response plan is part of the HIIPP, some of the requirements in 
paragraph (c) are relevant to the emergency response plan. For example, 
the employer would need to seek the input and involvement of non-

[[Page 70794]]

managerial employees and their representatives, if any, in the 
development and implementation of the emergency response plan (see 
proposed paragraph (c)(6)). See Explanation of Proposed Requirements 
for paragraph (c), for a detailed explanation of the requirements that 
apply to the HIIPP. Only one plan would be required for each employer 
(i.e., for the whole company). However, if the employer has multiple 
work sites that are distinct from each other, the plan would be 
tailored to each work site or type of work site. For instance, if an 
employer has employees engaged in work activities outdoors on a farm, 
as well as employees loading and unloading product from vehicles at 
various locations, the employer could have one emergency response plan 
with the specifications for each of these types of work sites 
represented. Employers may also choose to include other elements in the 
plan to account for any work activities unique to their workplace.
    Proposed paragraph (g)(1)(i) would require employers to include a 
list of emergency phone numbers (e.g., 911, emergency services) in 
their emergency response plan. Indicating the most appropriate phone 
number(s) to contact in the case of an emergency helps ensure medical 
support and assistance are provided timely and efficiently during a 
heat emergency. Examples of other phone numbers for assistance aside 
from 911 that employers might include in the plan are those for on-site 
clinicians or nurses to be contacted if an employee is experiencing 
signs and symptoms of a heat-related illness.
    Proposed paragraph (g)(1)(ii) would require employers to include a 
description of how employees can contact a supervisor and emergency 
medical services in their emergency response plan. Because time is of 
the essence in emergency situations, it is important that employees 
know beforehand how to contact a supervisor and emergency medical 
services in the event of a heat emergency. For example, if employees do 
not have phone service or access to a phone to call for medical help, 
but they do have access to other means of communication such as radios, 
walkie-talkies, personal locator beacons, and audio signals, the 
employer's plan would describe how to use these other means of 
communication to contact a supervisor and emergency medical services.
    Proposed paragraph (g)(1)(iii) would require the emergency response 
plan to include the individual(s) designated to ensure that heat 
emergency procedures are invoked when appropriate. Clearly assigning 
this responsibility to an individual(s) can reduce confusion and allow 
for swift action in the event of a heat emergency. Employers with 
multiple work sites or dispersed work areas may not be able to ensure 
heat emergency procedures are invoked without designating different 
individuals for each work site/area. For example, an employer with work 
activities inside two factories in different geographic locations would 
need to designate an individual(s) to ensure heat emergency procedures 
are invoked at each factory location.
    Proposed paragraph (g)(1)(iv) would require the emergency response 
plan to have a description of how to transport employees to a place 
where they can be reached by an emergency medical provider. Planning 
for where employees can access emergency medical services can ensure 
aid is provided efficiently. This is especially important for employers 
with employees engaging in work activities in remote locations, where 
medical services cannot reach them. For example, an employee working in 
an area of a farm not easily accessible by vehicle or an employee in a 
difficult to reach location inside a building being constructed.
    Proposed paragraph (g)(1)(v) would require the emergency response 
plan to include clear and precise directions to the work site, 
including the address of the work site, which can be provided to 
emergency dispatchers. For certain work sites that are remote/hard to 
reach or do not have an address, GPS coordinates may be necessary to 
share with emergency responders, or a description of how to get to 
their location from the main road, entrance, building, etc. If an 
employee's work site changes frequently, the emergency response plan 
would need to include a clear strategy to account for their changing 
locations and ensure directions to the work site are readily accessible 
when needed to provide to emergency dispatchers.
    Proposed paragraph (g)(1)(vi) would require the emergency response 
plan to include procedures for responding to an employee experiencing 
signs and symptoms of heat-related illness, including heat emergency 
procedures for responding to an employee with suspected heat stroke. 
Prior development of emergency response procedures can ensure 
assistance and medical attention are provided efficiently and quickly. 
In developing the procedures, OSHA expects that employers would look to 
resources such as OSHA guidance (e.g., www.osha.gov/heat-exposure/illness-first-aid) and NIOSH recommendations (NIOSH, 2016) for more 
information.
    The proposed standard does not require employers to develop a plan 
for each work site. However, the employer's emergency response plan(s) 
must contain all the information required by paragraphs (g)(1)(i) 
through (vi), some of which will vary based on work site. The employer 
may be able to incorporate the information needed for different work 
sites into the same emergency response plan. For instance, if an 
employer has employees engaged in work activities outdoors on a farm, 
as well as employees loading and unloading product from vehicles at 
various locations, the employer could have one emergency response plan 
with the specifications for each of these types of work sites 
represented. Employers may also choose to include elements beyond those 
required by paragraphs (g)(1)(i) through (vi) in their plan to account 
for any work activities unique to their workplace.
    Proposed paragraph (g)(2) specifies the actions employers would be 
required to perform if an employee is experiencing signs and symptoms 
of heat-related illness. Under proposed paragraph (b) signs and 
symptoms of heat-related illness means the physiological manifestations 
of a heat-related illness and includes headache, nausea, weakness, 
dizziness, elevated body temperature, muscle cramps, and muscle pain or 
spasms.
    Proposed paragraph (g)(2)(i) would require employers to relieve 
from duty employees who are experiencing signs and symptoms of heat-
related illness. Relieving the employee from duty would allow the 
employer to address the heat-related illness according to the 
procedures outlined in proposed paragraphs (g)(2)(ii) through (v). This 
relief from duty, including the time it takes to address the heat-
related illness according to the procedures outlined in proposed 
paragraphs (g)(2)(ii) through (v), must be with pay and must continue 
at least until symptoms have subsided.
    Proposed paragraph (g)(2)(ii) would require that employers monitor 
employees who are experiencing signs and symptoms of heat-related 
illness, and proposed paragraph (g)(2)(iii) would require employers to 
ensure that employees who are experiencing signs and symptoms of heat-
related illness are not left alone. Continuous monitoring of employees 
who are experiencing signs and symptoms of a heat-related illness is 
important to ensure that if the employee's condition progresses to a 
heat emergency, someone is there to observe it and quickly respond.
    Proposed paragraph (g)(2)(iv) would require employers to offer 
employees who are experiencing signs and

[[Page 70795]]

symptoms of heat-related illness on-site first aid or medical services 
before ending any monitoring. This requirement is intended to be 
consistent with existing first aid standards (e.g. 29 CFR 1910.151, 
1915.87, 1926.23 and 1926.50), which require accessibility of medical 
services and first aid to varying degrees depending on the industry or 
whether the workplace is near an infirmary, clinic or hospital. 
Proposed paragraph (g)(2)(iv) would not add new requirements for staff 
to be fully trained in first aid. Employers would offer the first aid 
or medical resources they have available to employees on site to the 
extent already required by first aid standards and follow the 
procedures developed in paragraph (g)(1)(vi) as applicable.
    Proposed paragraph (g)(2)(v) would require employers to provide 
employees who are experiencing signs and symptoms of heat-related 
illness with means to reduce their body temperature. Examples of means 
to reduce body temperature are instructing those employees to remove 
all PPE and heavy outer clothing (e.g., heavy/impermeable protective 
clothing) and moving them to a cooled or shaded area (e.g., the break 
areas required under paragraphs (e)(3) and (4)) where they can sit and 
drink cool water. If the employer has cooling PPE (e.g., cooling 
bandanas or neck wraps, and vests and cooling systems such as hybrid 
personal cooling systems (HPCS), and fans) available on site, those 
could also be used to cool employees as well. (For information related 
to the requirement to reduce an employee's body temperature in the case 
of a heat emergency, see discussion below.)
    Proposed paragraph (g)(3) specifies the actions employers would 
have to perform if an employee is experiencing signs and symptoms of a 
heat emergency. Proposed paragraph (b) defines signs and symptoms of a 
heat emergency as the physiological manifestations of a heat-related 
illness that requires emergency response and includes loss of 
consciousness (i.e., fainting, collapse) with excessive body 
temperature, which may or may not be accompanied by vertigo, nausea, 
headache, cerebral dysfunction, or bizarre behavior. This could also 
include staggering, vomiting, acting irrationally or disoriented, 
having convulsions, and (even after resting) having an elevated heart 
rate.
    Proposed paragraph (g)(3)(i) would require employers to take 
immediate actions to reduce the employee's body temperature before 
emergency medical services arrive. Rapid cooling of body temperature 
during a heat emergency is essential because the potential for organ 
damage and risk of death increase in a short period of time, often 
before medical personnel can respond, transport, and treat the affected 
individual (Belval et al., 2018). Immersion in ice water or cold water 
has been reported to have the fastest cooling rates (McDermott et al., 
2009b; Casa et al., 2007). However, OSHA realizes that immersing an 
employee in a tub of ice/cold water is not an option that will be 
available at most work sites. Other, more practical methods of reducing 
employee body temperature using materials that employers are likely to 
have, or are similar to materials that an employer is likely to have, 
on site have been reported to be highly effective in preventing death 
from exertional heat stroke. DeGroot et al. (2023) reported survival of 
362 of 363 military personnel who were suffering from exertional heat 
stroke and were treated with strategically placed ``ice sheets'' (i.e., 
bed sheets soaked in ice water). McDermott et al. (2009a) reported 100% 
survival in nine marathon runners who were suffering from exertional 
heat stroke and treated by dousing with cold water and rubbing of ice 
bags over major muscle groups. Another possible approach is the tarp-
assisted cooling oscillation (TACO) method that involves wrapping the 
affected individual in a tarp with ice (Luhring et al., 2016).
    Proposed paragraph (g)(3)(ii) would require employers to contact 
emergency medical services immediately for employees experiencing signs 
and symptoms of a heat emergency, and proposed paragraph (g)(3)(iii) 
would require employers to also perform the activities described in 
paragraphs (g)(2)(i) through (iv) to aid an employee during a heat 
emergency until emergency medical services arrives. Some heat-related 
illnesses can quickly progress and become fatal (see Section IV., 
Health Effects). The severity and survival of heat stroke is highly 
dependent on how quickly effective cooling and emergency medical 
services are provided (Vicario et al., 1986; Demartini et al., 2015; 
Belval et al., 2018).
A. Requests for Comments
    OSHA requests comments and evidence regarding the following:
     Whether OSHA should require a minimum duration of time an 
employee who has experienced signs and symptoms of heat-related illness 
must be relieved from duty, and what an appropriate duration of time 
would be before returning employees to work;
     Whether OSHA should add or remove any signs or symptoms in 
the definitions of signs and symptoms of heat-related illness and signs 
and symptoms of a heat emergency in proposed paragraph (b). If so, 
provide clear and specific evidence for inclusion or exclusion;
     Whether paragraph (g)(3)(i) should require specific 
actions that the employer must take to reduce an employee's body 
temperature before emergency medical services arrive, rather than 
merely requiring unspecified ``immediate actions''. If so, describe 
those specific actions; and
     Whether paragraph (g)(3)(i) should prohibit certain 
actions to reduce an employee's body temperature before emergency 
medical services arrive. If so, indicate if there is evidence or 
observations that certain actions are not helpful or are 
counterproductive.

H. Paragraph (h) Training

    Paragraph (h) of the proposed standard establishes requirements for 
training on HRI prevention. It addresses the topics to be addressed in 
training, the types of employees who are to be trained, the frequency 
of training, triggers for supplemental training, and how training is to 
be conducted. OSHA regularly includes training requirements in its 
standards to ensure employees understand the hazards addressed by the 
standard, the protections they are entitled to under the standard, and 
the measures to take to protect themselves. Here, OSHA believes that it 
is essential that employees are trained on heat-related hazards and how 
to identify signs and symptoms of HRIs as well as on the requirements 
of the proposed standard and the employer's heat-related policies and 
procedures. This training ensures that employees understand heat 
hazards and the workplace specific control measures that would be 
implemented to address the hazard. The effectiveness of the proposed 
standard would be undermined if employees did not have sufficient 
knowledge and understanding to identify heat hazards and their health 
effects or sufficient knowledge and understanding of their employer's 
policies and procedures for addressing those hazards.
    Surveys and interviews with diverse working populations highlight 
the need for additional education and training on HRIs and prevention 
strategies amongst employees (Luque et al., 2020; Smith et al., 2021; 
Fleischer at al., 2013; Stoecklin-Marois et al., 2013; Langer et al., 
2021; Jacklitsch et al., 2018). The NACOSH Heat Injury and Illness 
Prevention Work Group recommended that both workers and supervisors are 
trained in heat illness and injury

[[Page 70796]]

prevention strategies. Additionally, the Work Group recommended that 
the training program includes the following elements: identification of 
hazards; mitigation of hazards through prevention; reporting of signs 
and symptoms; and emergency response. OSHA preliminarily finds that 
effective training is an essential element of any heat injury and 
illness prevention program and that the requirements in proposed 
paragraph (h) are necessary and appropriate to ensure the effectiveness 
of the standard as a whole.
    Proposed paragraph (h)(1) establishes the initial training 
requirements for all exposed employees. It would require employers to 
ensure that each employee receives, and understands, training on the 
topics outlined in proposed paragraphs (h)(1)(i) through (xvi) prior to 
the employee performing any work at or above the initial heat trigger. 
Requiring that initial training occur before employees perform any work 
at or above the initial heat trigger ensures that the employees have 
all the knowledge necessary to protect themselves prior to their 
exposure to the hazard.
    This provision, like paragraphs (h)(2) through (h)(4), would 
require employers to ensure that employees, including supervisors and 
heat safety coordinators, understand the training topics. While OSHA 
does not mandate testing or specific modes of ascertaining employee 
understanding of the training materials, OSHA expects that all required 
training will include some measure of comprehension. Different ways 
that employers could ensure comprehension of the training materials 
include a knowledge check (e.g., written or oral assessment) or 
discussions after the training. Post training assessments may be 
particularly useful for ensuring employee participation and 
comprehension when employers offer online training. Proposed paragraph 
(h)(5), discussed below, includes additional requirements for 
presentation of the training.
    Proposed paragraph (h)(1)(i) would require employers to provide 
training on heat stress hazards. Heat stress is the total heat load on 
the body. There are three major types of hazards which contribute to 
heat stress: (1) environmental factors such as high humidity, high 
temperature, solar radiation, lack of air movement, and process heat 
(i.e., radiant heat produced by machinery or equipment, such as ovens 
and furnaces), (2) use of personal protective equipment or clothing 
that can inhibit the body's ability to cool itself, and (3) the body's 
metabolic heat (i.e., heat produced by the body during work involving 
physical activity and exertion). Employers should make employees aware 
of all the sources of heat at the workplace that contribute to heat 
stress.
    Proposed paragraph (h)(1)(ii) would require employers to provide 
training on heat-related injuries and illnesses. See Section IV., 
Health Effects, for a discussion of HRIs. Examples of heat-related 
illnesses include heat stroke, heat exhaustion, heat cramps, heat 
syncope, and rhabdomyolysis. Heat-related injuries that could result 
from heat illness include slips, trips, falls, and other injuries that 
could result from the mishandling of equipment due to the effects of 
heat stress.
    Proposed paragraph (h)(1)(iii) would require employers to provide 
training on risk factors for heat-related injury or illness, including 
the contributions of physical exertion, clothing, personal protective 
equipment, a lack of acclimatization, and personal risk factors (e.g., 
age, health, alcohol consumption, and use of certain medications). As 
noted above, physical exertion, clothing, and personal protective 
equipment all increase an employee's heat load. More information on 
acclimatization and how it affects risk is included in Section V.C., 
Risk Reduction, and more information about personal risk factors is 
included in Section IV.O., Factors that Affect Risk for Heat-Related 
Health Effects.
    Proposed paragraph (h)(1)(iv) would require employers to provide 
training on signs and symptoms of heat-related illness and which ones 
require immediate emergency action. As defined in proposed paragraph 
(b), signs and symptoms of heat-related illness means the physiological 
manifestations of a heat-related illness and includes headache, nausea, 
weakness, dizziness, elevated body temperature, muscle cramps, and 
muscle pain or spasms. Also defined in proposed paragraph (b), signs 
and symptoms of a heat emergency means the physiological manifestations 
of a heat-related illness that requires emergency response and includes 
loss of consciousness (i.e., fainting, collapse) with excessive body 
temperature, which may or may not be accompanied by vertigo, nausea, 
headache, cerebral dysfunction, or bizarre behavior. This could also 
include staggering, vomiting, acting irrationally or disoriented, 
having convulsions, and (even after resting) having an elevated heart 
rate. Employers must train employees on how to identify these signs and 
symptoms of heat-related illness in themselves and their coworkers and 
when to employ the employer's emergency response procedures, as 
required under proposed paragraph (g). That provision specifies the 
actions that an employer must take both when an employee experiences 
signs and symptoms of a heat-related illness and when an employee 
experiences signs and symptoms of a heat emergency. For further 
discussion see the Explanation of Proposed Requirements for Paragraph 
(g).
    Proposed paragraphs (h)(1)(v) through (vii) would require employers 
to train employees on the importance of removing PPE that may impair 
cooling during rest breaks, taking rest breaks to prevent heat-related 
illness or injury, and that rest breaks are paid, and drinking water to 
prevent heat-related illness or injury. Removing PPE when possible, 
allows employees to cool down faster during rest breaks. As discussed 
in Section V.C., Risk Reduction, drinking adequate amounts of water and 
taking rest breaks are important for reducing heat strain that could 
lead to HRI. Training on these topics could give the employer an 
opportunity to address common misperceptions regarding heat, such as 
that drinking cold water in the heat is harmful. In addition, proposed 
paragraph (h)(1)(viii) and (ix) would require that employers train 
employees on where break areas and employer provided water are located. 
This would ensure employees are aware of the locations of break areas 
and water and encourage their effective utilization.
    Proposed paragraph (h)(1)(x) would require employers to train 
employees on the importance of reporting signs and symptoms of heat-
related illnesses that they experience personally or those they observe 
in co-workers. Training employees to be observant of and to report 
early any signs and symptoms of heat-related illnesses they see at the 
workplace is a key factor to identifying and addressing potential heat-
related incidents before they result in a serious illness or injury. In 
addition, employers should ensure that employees are familiar with the 
employer's own procedures for reporting signs and symptoms of a heat 
emergency or heat-related illness pursuant to its heat emergency 
response plan as required in proposed paragraph (g).
    Proposed paragraph (h)(1)(xi) would require employers to train 
employees on all the policies and procedures applicable to the 
employee's duties, as indicated in the work site's HIIPP. Employees 
play an important role in effective implementation of the employer's 
work site-specific policies and procedures to prevent heat-related 
illnesses and injury, and training on these policies and procedures is

[[Page 70797]]

necessary to ensure that they are implemented effectively. OSHA 
recognizes that employees perform various duties and therefore likely 
need different types of training, and the proposed requirement allows 
employers flexibility to account for these differences in their 
training programs. Thus, certain components of the training may need to 
be tailored to an employee's assigned duties. For example, while all 
employees would require training on recognizing signs and symptoms of 
heat-related illness, employees observing a co-worker as part of buddy 
system under proposed paragraph (f)(3)(i) may require additional 
training on how to report signs and symptoms according to the policies 
and procedures established and implemented by the employer. In another 
example, the individual designated by the employer to ensure that 
emergency procedures are invoked when appropriate under proposed 
paragraph (g)(1)(iii) might require more detailed training on the 
employer's heat emergency response procedures. Another example could be 
training employees who wear vapor-impermeable clothing on the policies 
and procedures the employer has implemented to protect them under 
proposed paragraph (c)(3).
    Proposed paragraph (h)(1)(xii) would require employers to train 
employees on the identity of the heat safety coordinator. Under 
proposed paragraph (c)(5), the heat safety coordinator would be 
designated to implement and monitor the HIIPP and would be given 
authority to ensure compliance with the HIIPP. Therefore, employees 
could contact the heat safety coordinator to ask questions about the 
HIIPP, to provide feedback on the policies and procedures, or report 
possible deficiencies with implementation of the HIIPP. Employers 
should encourage employees to contact the heat safety coordinator for 
these reasons. To ensure that employees are able to contact the heat 
safety coordinator, employers could provide the name of the individual 
and other information needed to contact them as part of the training 
required under this paragraph.
    Proposed paragraph (h)(1)(xiii) would require employers to train 
employees on the requirements of this standard. While proposed 
paragraph (h)(1)(xi) would require training on all policies and 
procedures applicable to an employee's duties as noted in the 
employer's HIIPP, training under (h)(1)(xiii) would ensure that 
employees are familiar with all requirements of this proposed standard. 
For example, employees would have to be informed of the requirements 
related to employee participation, including in the development, 
implementation, review and update of the HIIPP under proposed paragraph 
(c), and identifying work areas with reasonable expectations of 
exposures at or above the initial heat trigger, and in developing and 
updating the monitoring plan under proposed paragraph (d). Employees 
would also need to be informed that requirements of the proposed 
standard would be implemented at no cost to employees under proposed 
paragraph (j). The proposed provision would also ensure that employees 
are made familiar with the employer's heat-related policies and 
procedures.
    Proposed paragraph (h)(1)(xiv) would require employers to train 
employees on how to access the work site's HIIPP. If relevant this 
would include training on how to access both digital or physical 
copies.
    Proposed paragraph (h)(1)(xv) would require employers to train 
employees on their right to protections under this standard (e.g., rest 
breaks, water), and that employers are prohibited from discharging or 
in any manner discriminating against any employee for exercising those 
rights. Employees' right to be free from retaliation for availing 
themselves of the protections of the standard or for raising safety 
concerns comes from section 11(c) of the OSH Act, 29 U.S.C. 660(c), and 
requiring employers to train on these protections is consistent with 
the purpose of that provision. Proposed paragraph (h)(1)(xv) is also 
consistent with section 8(c)(1) of the Act, 29 U.S.C. 657(c)(1), which 
directs the Secretary to issue regulations requiring employers to keep 
their employees informed of their protections under the Act and any 
applicable standards, through posting of notices or ``other appropriate 
means.'' This training ensures that employees know that they have a 
right to the protections required by the standard. Having employers 
acknowledge and train their employees about their rights under this 
standard provides assurance that employees are aware of the protections 
afforded them and encourages them to exercise their rights without fear 
of reprisal. They may otherwise fear retaliation for utilizing the 
protections afforded them under the standard or for speaking up about 
workplace heat hazard concerns. This fear would undermine the 
effectiveness of the standard because employee participation plays a 
central role in effectuating the standard's purpose.
    Proposed paragraph (h)(1)(xvi) would require that if the employer 
is required under paragraph (f)(5) to place warning signs for 
excessively high heat areas, they would be required to train employees 
on procedures to follow when working in these areas. These procedures 
could include, but are not limited to, any PPE that might be required 
when working in those areas, if relevant, and reminders to remove PPE 
when taking rest breaks in break areas and should reinforce employees' 
access to rest breaks in break areas, required under paragraph (f)(2), 
and drinking water, required under paragraph (e)(2), as appropriate.
    Proposed paragraph (h)(2) would require the employer to ensure that 
each supervisor responsible for supervising employees performing any 
work at or above the initial heat trigger and each heat safety 
coordinator receives training on, and understands, both the topics 
outlined in paragraph (h)(1) and the topics outlined in paragraphs 
(h)(2)(i) and (ii). Proposed paragraph (h)(2)(i) would require the 
employer to train supervisors and heat safety coordinators on the 
policies and procedures developed to comply with the applicable 
requirements of this standard, including the policies and procedures 
for monitoring heat conditions developed to comply with paragraphs 
(d)(1) and (d)(3)(ii). Proposed paragraph (h)(2)(ii) would require the 
employer to train supervisors and heat safety coordinators on 
procedures they would have to follow if an employee exhibits signs and 
symptoms of heat related illness, which an employer is required to 
develop for its HIIPP pursuant to proposed paragraph (g)(1)(vi). This 
would ensure effective and rapid treatment and care for employees 
experiencing signs and symptoms of heat-related illness. OSHA included 
these proposed provisions to ensure that supervisors and heat safety 
coordinators receive additional training needed to perform their duties 
as specified in the proposed standard.
    Proposed paragraph (h)(3) would require the employer to ensure that 
each employee receives annual refresher training on, and understands, 
the subjects addressed in paragraph (h)(1) of the proposed standard. 
This paragraph would also require that each supervisor and heat safety 
coordinator additionally receive annual refresher training on, and 
understands, the topics addressed in paragraph (h)(2). OSHA 
preliminarily finds that annual training is needed to refresh and 
reinforce an employee's recollection and knowledge about the topics 
addressed in this paragraph. This proposed provision also indicates 
that for employees who perform work outdoors, the employer must conduct 
the annual refresher training before or at the start of the heat 
season. This can

[[Page 70798]]

vary depending on the weather conditions in the geographic region where 
the employer is located. Accordingly, OSHA intends this requirement to 
be flexible and to allow employers leeway to determine the start of the 
heat season, so long as those determinations are reasonable. For 
example, in northern States such as Michigan, employers might find it 
best to do annual training before the time when temperatures commonly 
reach the initial heat trigger or above. In those cases, temperatures 
are likely to be below the initial heat trigger for a substantial 
portion of the year and employees are likely to need reminders of all 
policies and procedures related to heat, both for the initial and high 
heat triggers. Employers can determine when heat season is for them 
based on normal weather patterns and would be required to conduct 
training prior to or at the start of the heat season. In most 
instances, OSHA expects that employers would do this no sooner than 30 
days before the start of their heat season, so that employees can 
recall training materials easily, rather than for example, 6-months 
before the start of heat season. For new employees at outdoor work 
sites, this may result in some employees receiving the annual refresher 
training less than a year after the initial training.
    Proposed paragraph (h)(4) specifies when supplemental training 
would be required. Proposed paragraph (h)(4)(i) would require the 
employer to ensure that employees promptly receive and understand 
additional training whenever changes occur that affect the employee's 
exposure to heat at work (e.g., new job tasks, relocation to a 
different facility or area of a facility). For example, if an employee 
is assigned to a new task or workstation that exposes them to high 
process heat or to outdoor work where the employee is exposed to 
hazardous heat, and such employee was not previously trained on the 
necessary topics required under this paragraph, then the employer would 
have to provide that employee with the requisite training. Similarly, 
if an employee is assigned to a new work area to which different heat-
related policies and procedures apply, they would need to be trained on 
these area-specific policies and procedures. Additional examples could 
include when an employer's work site experiences heat waves, when new 
heat sources are added to the workplace, or when employees are assigned 
to a new task where they need to wear vapor-impermeable PPE (i.e., non-
breathable). In these instances, the training required under this 
provision would have to comport with the requirements of the rest of 
this paragraph.
    Proposed paragraph (h)(4)(ii) would require that each employee 
promptly receives, and understands, additional training whenever 
changes occur in policies and procedures addressed in paragraph 
(h)(1)(xi) of this proposed standard. Proposed paragraph (c) would 
require employers to monitor their HIIPP to ensure ongoing 
effectiveness. When doing so, the employer may find that the policies 
and procedures are inadequate to protect employees from heat hazards. 
If so, the employer would have to update those policies and procedures. 
When this happens, employers would be required to train all employees 
on the new or altered policies and procedures so that the employees are 
aware of the new policies and procedures and how to follow them to 
reduce their risk of developing heat-related illnesses and injuries.
    Proposed paragraph (h)(4)(iii) would require that each employee 
promptly receives, and understands, additional training whenever there 
is an indication that an employee(s) has not retained the necessary 
understanding. Examples of this would include employees who appear to 
have forgotten signs and symptoms of heat-related illnesses or how to 
respond when an employee is experiencing those signs and symptoms. It 
is essential that employees remain familiar with training they have 
received so they continue to have the knowledge and skills needed to 
protect themselves and possibly co-workers from heat hazards. 
Supplemental training under paragraph (h)(4)(iii) must be provided to 
those employees who have demonstrated a lack of understanding or 
failure to follow the employer's heat policies and procedures or comply 
with the requirements of this proposed standard.
    Proposed paragraph (h)(4)(iv) would require that each employee 
promptly receives, and understands, additional training whenever a 
heat-related injury or illness occurs at the work site that results in 
death, days away from work, medical treatment beyond first aid, or loss 
of consciousness. Occurrences of these types of heat-related injuries 
and illnesses could indicate that one or more employees are not 
following policies and procedures for preventing or responding to heat-
related illnesses and injuries. After a heat-related illness or injury 
in the workplace occurs that meets the requirements of proposed 
paragraph (h)(4)(iv), OSHA expects that each employee would receive 
supplemental training. This training could be a ``lessons learned'' or 
``alert'' type training.
    Both initial and supplemental training are important components of 
an effective heat injury and illness prevention program. Initial 
training provides employees with the knowledge and skills they need to 
protect themselves against heat hazards, and also emphasizes the 
importance of following workplace policies and procedures in the HIIPP. 
Supplemental training ensures employees continue to have the knowledge 
and skills they need to protect themselves from heat hazards. It 
provides an opportunity to present new information that was not 
available during the initial training or that becomes relevant when an 
employee's duties change. Additionally, supplemental training is 
necessary when an employee demonstrates that they have not retained 
information from the initial training (e.g., by failing to follow 
appropriate policies and procedures). Supplemental training does not 
necessarily need to include all information covered in the initial 
training, as only some policies or procedures may need to be reviewed, 
and employees will receive a full refresher training annually.
    Proposed paragraph (h)(5) would require that all training provided 
under paragraphs (h)(1) through (4) is provided in a language and at a 
literacy level each employee, supervisor, and heat safety coordinator 
understands. In addition, the provision would require that the employer 
provide employees with an opportunity for questions and answers about 
the training materials. For the training to be effective, the employer 
must ensure that it is provided in a manner that the employee is able 
to understand. Employees have varying educational levels, literacy, and 
language skills, and the training must be presented in a language, or 
languages, and at a level of understanding that accounts for these 
differences. This may mean, for example, providing materials, 
instruction, or assistance in Spanish rather than English if the 
employees being trained are Spanish-speaking and do not understand 
English. The employer is not required to provide training in the 
employee's preferred language if the employee understands both 
languages; as long as the employee is able to understand the material 
in the language used, the intent of the proposed standard would be met. 
As explained above with respect to paragraph (h)(1), OSHA does not 
mandate testing or specific modes of ascertaining employee 
understanding of the training materials, but expects that

[[Page 70799]]

all required training will include some measure of comprehension.
    The proposed provision does not specify the manner in which 
training would be delivered. Employers may conduct training in various 
ways, such as in-person (e.g., classroom instruction or informal 
discussions during safety meetings/toolbox talks), virtually (e.g., 
videoconference, recorded video, online training), using written 
materials, or any combination of those methods. However, this paragraph 
would require the employer to provide an opportunity for employees to 
ask questions regardless of the medium of training. It is critical that 
trainees have the opportunity to ask questions and receive answers if 
they do not fully understand the material that is presented to them. If 
it is not possible to have someone present or available during the 
training, employers could provide the contact information of the 
individual that employees can contact to answer their questions (e.g., 
an email or telephone contact). OSHA expects employers to make an 
effort to respond to questions promptly.
A. Requests for Comments
    OSHA requests comments and evidence regarding the following:
     Whether the agency should require other training topics in 
the standard;
     Whether the inclusion of separate training requirements 
for supervisors and heat safety coordinators is appropriate, or whether 
the duty-specific training requirements in proposed paragraph (h)(1) 
are sufficient;
     Whether the agency has identified appropriate triggers for 
supplemental training;
     Whether the agency should require annual refresher 
training or whether the more performance-based supplemental training 
requirements are sufficient; and
     Whether the agency should specify certain criteria that 
define the start of heat season.

I. Paragraph (i) Recordkeeping

    Paragraph (i) of the proposed standard would require certain 
employers to create written or electronic records of on-site 
temperature measurements and establishes the duration of time that 
employers must retain those records. Specifically, it applies to 
employers that have indoor work areas where there is a reasonable 
expectation that employees are or may be exposed to heat at or above 
the initial heat trigger, and that are therefore required to conduct 
on-site temperature measurements under paragraph (d)(3)(ii). These 
employers must have and maintain written or electronic records of these 
measurements. Under paragraph (i), employers must retain these records 
for a minimum of six months.
    Maintaining these records, whether written or electronic, serves 
several purposes. It will assist OSHA in determining conditions at the 
work site, which will facilitate OSHA's ability to verify employers' 
compliance with the standard's provisions. Additionally, these records 
may facilitate employers identifying trends in indoor temperatures and 
their effect on employee health and safety. In the event of a heat-
related injury or illness, these records can help employers assess the 
conditions at the time of the injury or illness in order to prevent 
such an event from recurring.
    Paragraph (i) applies to indoor work areas only. This is because 
employers cannot accurately rely on weather forecasting to predict and 
monitor temperatures in these areas like they can for outdoor work 
areas. It is therefore not possible for OSHA or the employer to 
recreate historic temperature records for indoor work areas in the 
absence of on-site temperature measurement records. OSHA has 
preliminarily determined that six months is an appropriate timeframe 
for records retention because this is the maximum time permitted for an 
OSHA investigation (see 29 U.S.C. 658(c)). There are several 
commercially available heat monitoring devices that are capable of 
maintaining electronic logs of recorded measurements for six months 
(ERG, 2024b). Therefore, employers can comply with the recordkeeping 
requirement by using monitoring devices with sufficient storage 
capability. Alternatively, employers could comply by creating and 
maintaining written records based on monitoring devices that do not 
have digital recording capabilities.
A. Requests for Comments
    OSHA requests comments and evidence regarding the following:
     Whether six months is an appropriate and feasible duration 
of time to maintain records of monitoring data;
     Whether permitting employers to maintain records on 
devices that store data locally is appropriate; and
     Whether the standard should require retention of any other 
records, and if so, for what duration.

J. Paragraph (j) Requirements Implemented at no Cost to Employees

    Proposed paragraph (j) provides that implementation of all 
requirements of the standard must be at no cost to employees, including 
paying employees their normal rate of pay when compliance requires 
employee time. This provision is included to make it clear that the 
employer is responsible for all costs associated with implementing the 
standard, including not only direct monetary expenses to the employee, 
but also reasonable time to perform required tasks and training.
    This proposed requirement is consistent with the OSH Act, which 
requires employers to ensure a safe and healthful workplace. The OSH 
Act reflects Congress's determination that the costs of compliance with 
the Act and OSHA standards are part of the cost of doing business and 
OSHA may foreclose employers from shifting those costs to employees 
(see Am. Textile Mfrs. Inst., Inc. v. Donovan, 452 U.S. 490, 514 
(1981); Phelps Dodge Corp. v. OSHRC, 725 F.2d 1237, 1239-40 (9th Cir. 
1984); see also Sec'y of Labor v. Beverly Healthcare-Hillview, 541 F.3d 
193, 198-201 (3d Cir. 2008)). The proposed requirement is also 
consistent with OSHA's longstanding practice in prior rulemakings. See, 
e.g., Employer Payment for Personal Protective Equipment; 72 FR 64342, 
64344 (Nov. 15, 2007); Occupational Exposure to Bloodborne Pathogens, 
56 FR 64004, 64125 (Dec. 1991). The intent of proposed paragraph (j) is 
that the standard be implemented at no cost to employees because 
employer payment for items, such as access to water and shade, is 
necessary to ensure employees are provided safe working conditions and 
are protected from the hazard of heat stress. Employees are more likely 
to take advantage of various workplace protections if such protections 
are provided at no cost to them. Moreover, as explained in Section 
VIII., Distributional Analysis, workers from underserved populations 
are disproportionately exposed to occupational heat hazards. For all 
workers, but particularly more vulnerable workers, protection from 
occupational hazards must not depend on workers' ability to pay for 
those protections. In indicating that the implementation of all 
requirements of this standard must be at no cost to the employee, OSHA 
considers costs to include not only direct monetary expenses to the 
employee, but also the time and other expenses necessary to perform 
required tasks.
    The following discussion highlights specific proposed requirements 
in paragraphs (c) Heat injury and illness prevention plan, (d) 
Identifying heat hazards, (e) Requirements at or above the initial heat 
trigger, (f) Requirements at or above the high heat trigger, (g) Heat 
illness and emergency response

[[Page 70800]]

and planning, and (h) Training. This discussion is illustrative of the 
requirement that employees are not to bear the costs of implementing 
the standard. However, the requirement in proposed paragraph (j) 
applies to all provisions of the proposed standard, including employee 
time spent to implement or comply with those provisions.
    Proposed paragraphs (c)(6) and (7) would require employers to seek 
the input and involvement of non-managerial employees and their 
representatives, if any, in the development and implementation of the 
heat injury and illness prevention plan (HIIPP) and during any reviews 
or updates of the HIIPP. Similarly, proposed paragraph (d)(3)(iv) would 
require the employer to seek the input and involvement of non-
managerial employees and their representatives, if any, when evaluating 
the work site to identify work areas with a reasonable expectation of 
exposures at or above the initial heat trigger and in developing and 
updating monitoring plans. Under these paragraphs, the employer would 
be required to cover the expenses of non-managerial employees such as 
any travel costs that may be necessary, and to pay employees their 
normal rate of pay for the time necessary to engage in the development, 
implementation, and the required reviews and updates of the employer's 
HIIPP and monitoring plan.
    Proposed paragraph (e)(2) would require the employer to provide 
access to potable water for drinking that is placed in locations 
readily accessible to the employee, suitably cool, and of sufficient 
quantity to provide access to 1 quart of drinking water per employee 
per hour. To ensure this is provided at no cost to employees, the 
employer would not only need to pay for the water, its container, and 
the means to utilize the water (cups, bottles, etc.) but would be 
required to pay employees their normal rate of pay for time necessary 
to consume water and any time that may be necessary to travel to and 
from the location where water is provided. For example, if an employee 
works in an area where water cannot be made available due to safety 
considerations (e.g., certain areas in foundries) or because of the 
presence of toxic materials, and must walk to a water fountain in a 
break room to obtain water, the employer would be required to pay the 
employee for the time required to walk to the water fountain, consume 
water, and return to the work area.
    Proposed paragraph (e)(7) would require employers to implement an 
acclimatization protocol for new and returning employees when they 
would be exposed to heat at or above the initial heat trigger except 
when the employer can demonstrate the employee consistently worked 
under the same or similar conditions as the employer's working 
conditions within the prior 14 days. An acclimatization protocol sets 
forth the process whereby employees gradually adapt to work in the 
heat. Proposed paragraph (e)(7)(i) specifies the acclimatization 
protocol for new employees exposed to heat at or above the initial heat 
trigger during their first week on the job. The employer would have a 
choice to either: (A) implement an acclimatization plan that, at 
minimum, would include the measures in proposed paragraph (f) (i.e., 
rest breaks, observation for signs and symptoms of heat-related 
illness, a hazard alert, and warning signs at excessively high heat 
areas); or (B) provide for gradual acclimatization to heat in which 
employee exposure to heat is restricted to no more than 20% of a normal 
work shift exposure duration on the first day of work, 40% on the 
second day of work, 60% of the third day of work, and 80% on the fourth 
day of work. Proposed paragraph (e)(7)(ii) specifies the 
acclimatization protocol for returning employees (i.e., employees who 
have been away (e.g., on vacation or sick leave) for more than 14 days) 
exposed to heat at or above the initial heat trigger during their first 
week back on the job. The employer would have a choice to either: (A) 
implement an acclimatization plan that, at minimum, would incorporate 
the measures in proposed paragraph (f) whenever the heat index is at or 
above the initial heat trigger during the employee's first week upon 
returning to work; or (B) provide for gradual acclimatization to heat 
in which employee exposure to heat is restricted to no more than 50% of 
a normal work shift exposure during the first day of work, 60% on the 
second day of work, and 80% on the third day of work.
    An employer who chooses to provide a plan for gradual 
acclimatization to heat in which employee exposure to heat is 
restricted would be required to compensate the employee for the hours 
they would typically be expected to work, i.e., the employee's normal 
full shift, after acclimatization. For example, if a new employee would 
be expected to work 8 hours on a normal shift after acclimatization and 
the new employee would be restricted to 50% exposure during the normal 
work shift or 4 hours on the first day, the employer would be required 
to compensate the employee at their normal rate of pay for the full 8 
hours even if the employee worked for only 4 hours.
    OSHA anticipates that many employers would provide employees with 
other work (e.g., work activities performed in indoor work areas or 
vehicles where air-conditioning consistently keeps the ambient 
temperature below 80 [deg]F, sedentary work activities at indoor work 
sites) during the acclimatization period when they are restricted from 
duties that involve exposure to heat at or above the initial heat 
trigger. Employees would still be able to work a full 8-hour shift as 
long as their duration of exposure to heat at or above the initial heat 
trigger is limited to the specified duration.
    Proposed paragraphs (e)(8) and (f)(2) would require that employees 
be paid during the rest breaks required by those provisions. OSHA finds 
it important that employees be paid during the breaks to which they are 
entitled under the standard so that employees are not financially 
penalized and thus discouraged from taking advantage of those 
protections. For employees compensated on an hourly basis, this means 
employees would need to receive the same hourly rate of pay during rest 
breaks required by paragraphs (e)(8) and (f)(2) as they would receive 
while working.
    Some employees are paid on a piece-rate basis, meaning they are 
compensated based on factors such as jobs completed, quantity of 
produce picked, or products produced. Examples of employees compensated 
on a piece-rate basis include agricultural employees paid by the pound 
of produce picked, mechanics paid for each type of job completed (e.g., 
oil change or tune-up), warehouse employees paid by the number and size 
of orders filled, manufacturing employees paid by the number of 
products manufactured, or construction employees paid by the size and 
type of job completed. Employees paid on a piece-rate basis may be 
especially reluctant to take breaks. In a study by Wadsworth et al., 
2019, focus group discussions with piece-rate farm employees revealed 
that many expressed concerns about possible losses in earnings and that 
they might be replaced by another employee if they took breaks, and 
many such employees brought their own water to work to reduce the time 
they are not picking produce.
    To ensure piece rate employees are not discouraged from taking rest 
breaks, the proposed standard would require employers to compensate 
them at their normal rate of pay for time necessary for rest breaks. In 
the context of piece rate

[[Page 70801]]

employees and for purposes of this proposed standard, OSHA intends the 
phrase ``normal rate of pay'' to mean the rate that results from the 
following approach, which has also been adopted by the State of 
California (Cal. Lab. Code section 226.2 (eff. Jan 1, 2021)): employers 
would determine the normal rate of pay for piece-rate employees by 
dividing the total weekly pay by the total hours worked during the work 
week, not including heat-related rest breaks. That value would be 
multiplied by the total time of heat-related rest breaks to determine 
how much employees need to be paid for those breaks. For example, if a 
piece-rate employee works a 5-day work week, 8 a.m. to 4:30 p.m. with a 
30-minute unpaid lunch break from 12-12:30 each day, and earns $600 in 
piece rate pay for the week, and under proposed paragraph (f)(2) the 
employer would be obligated to provide two 15-minute heat-related rest 
breaks per day (i.e., the employee is exposed at or above the high heat 
trigger from 8 a.m. to 4:30 p.m. each day), that employee would receive 
a normal rate of pay of $16/hour for heat-related rest breaks based on 
the following formula:

Formula for Heat-Related Rest Break Compensation of Piece-rate 
Employees
    Total heat-related rest break time/week = 0.5 hours/day x 5 days/
week = 2.5 hours/week
    Hours worked, excluding non-meal heat-related breaks = 40 hours-2.5 
hours = 37.5 hours
    Heat-related rest break compensation per hour = $600 / 37.5 hours = 
$16/hour

    For an employee who also took rest breaks needed to prevent 
overheating under proposed paragraph (e)(8), the time of those rest 
break(s) would be added to the total heat-related rest break time per 
week to calculate the employee's normal rate of pay. OSHA has 
preliminarily determined that this approach accurately represents the 
normal rate of pay for piece-rate workers and thereby ensures that 
these workers would not lose pay when taking advantage of the 
standard's protection.
    Proposed paragraph (g)(2)(i) would require that an employee 
experiencing signs and symptoms of heat-related illness must be 
relieved from duty. The proposed standard would require the employer to 
pay employees their normal pay while they are relieved from duty until 
the signs and symptoms subside.
    Proposed paragraph (h) would establish requirements for training on 
heat hazards and associated protective measures. All training provided 
by the employer to meet the requirements of the standard would be 
required to be provided at no cost to the employee. The employer would 
be required to pay employees for time spent in training, including any 
time needed to travel to and from training.
A. Requests for Comments
    OSHA requests comments and information on the following:
     Whether OSHA should consider an alternative approach to 
calculating normal rate of pay for piece-rate employees, and what those 
alternative approaches are;
     Whether OSHA should make the calculation for piece rate 
workers' normal rate of pay explicit in paragraph (j); and
     Whether proposed paragraph (j) mandating that requirements 
be implemented at no cost to employees is adequate, or whether there 
are other potential costs to employees that OSHA should take into 
consideration.

K. Paragraph (k) Dates

    Paragraph (k) of the proposed standard would establish the 
effective date for the final standard and the date for compliance with 
the requirements specified in the standard. In paragraph (k)(1), OSHA 
proposes an effective date 60 days after the date of publication of the 
final standard in the Federal Register. This period is intended to 
allow affected employers the opportunity to familiarize themselves with 
the standard.
    Paragraph (k)(2) of the proposed standard would require employers 
to comply with all requirements of the standard 90 days after the 
effective date (150 days after the date of publication of the final 
standard in the Federal Register). The proposed compliance date is 
intended to allow adequate time for employers to undertake the 
necessary planning and preparation steps to comply with the standard. 
OSHA has preliminarily concluded that 90 days is sufficient time for 
employers to develop a heat injury and illness prevention plan (HIIPP), 
identify heat hazards in their workplace(s), implement the protective 
measures required under the standard, and provide required training to 
employees.
A. Requests for Comments
    OSHA solicits comment on the adequacy of the proposed effective and 
compliance dates. OSHA aims to ensure that protective measures are 
implemented as quickly as possible, while also ensuring that employers 
have sufficient time to implement these measures. In addition, the 
agency is interested in whether there are any circumstances that would 
warrant an alternative timeframe for compliance, including a shorter 
timeframe, and seeks comment on approaches that would phase in 
requirements of the standard.

L. Paragraph (l) Severability

    The severability provision, paragraph (l) of the proposed standard, 
serves two purposes. First, it expresses OSHA's intent that the general 
presumption of severability should be applied to this standard; i.e., 
if any section or provision of the proposed standard is held invalid or 
unenforceable or is stayed or enjoined by any court of competent 
jurisdiction, the remaining sections or provisions should remain 
effective and operative. Second, the severability provision also serves 
to express OSHA's judgment, based on its technical expertise, that each 
individual section and provision of the proposed standard remains 
workable in the event that one or more sections or provisions are 
invalidated, stayed, or enjoined; thus, the severance of any 
provisions, sections, or applications of the standard will not render 
the standard ineffective or unlawful as a whole. Consequently, the 
remainder of the standard should be allowed to take effect.
    With respect to this rulemaking, it is OSHA's intent that all 
provisions and sections be considered severable. In this regard, the 
agency intends that: (1) in the event that any provision within a 
section of the standard is stayed, enjoined, or invalidated, all 
remaining provisions within remain workable and shall remain effective 
and operative; (2) in the event that any whole section of the standard 
is stayed, enjoined, or invalidated, all remaining sections remain 
workable and shall remain effective and operative; and (3) in the event 
that any application of a provision is stayed, enjoined, or 
invalidated, the provision shall be construed so as to continue to give 
the maximum effect to the provision permitted by law.
    Although OSHA always intends for a presumption of severability to 
be applied to its standards, the agency has opted to include an 
explicit severability clause in this standard to remove any potential 
for doubt as to its intent. OSHA believes that this clarity is useful 
because of the multilayered programmatic approach to risk reduction it 
proposes here. The agency has preliminarily determined that the suite 
of programmatic requirements described in Section VII., Explanation of 
Proposed Requirements, is reasonably necessary and appropriate to 
protect employees from the significant risks posed by exposure to heat 
in the

[[Page 70802]]

workplace. While OSHA preliminarily finds that these requirements 
substantially reduce the risk of occupational injury and illness from 
exposure to heat when implemented together, the agency also believes 
that each individual requirement will independently reduce this risk to 
some extent, and that each requirement added to the first will result 
in a progressively greater reduction of risk. For example, should a 
reviewing court find the requirement of paragraph (f)(2), requiring 15 
minute rest breaks every two hours in high heat conditions invalid for 
some reason, the remainder of controls required by the standard in 
those conditions would still provide necessary protections to 
employees, and OSHA would intend that the rest of the standard should 
stand. Therefore, OSHA intends to have as many of the protective 
measures in this standard implemented as possible to reduce employees' 
risk of occupational injury, illness, and death from exposure to heat. 
Should a court of competent jurisdiction determine that any provision 
or section of this standard is invalid on its face or as applied, the 
court should presume that OSHA would have issued the remainder of the 
standard without the invalidated provision(s) or application(s). 
Similarly, should a court of competent jurisdiction determine that any 
provision, section, or application of this standard is required to be 
stayed or enjoined, the court should presume that OSHA intends for the 
remainder of the standard to take effect. See, e.g., Am. Dental Ass'n 
v. Martin, 984 F.2d 823, 830-31 (7th Cir. 1993) (affirming and allowing 
most of OSHA's bloodborne pathogens standard to take effect while 
vacating application of the standard to certain employers).

VIII. Preliminary Economic Analysis and Initial Regulatory Flexibility 
Analysis

    OSHA has examined the impacts of this rulemaking as required by 
Executive Order 12866 on Regulatory Planning and Review (September 
30,1993), Executive Order 13563 on Improving Regulation and Regulatory 
Review (January 18, 2011), Executive Order 14094 entitled ``Modernizing 
Regulatory Review'' (April 6, 2023), the Regulatory Flexibility Act 
(RFA) (September 19, 1980, Pub. L. 96354), section 202 of the Unfunded 
Mandates Reform Act of 1995 (March 22, 1995; Pub. L. 104-4), and 
Executive Order 13132 on Federalism (August 4, 1999).
    Executive Orders 12866 and 13563 direct agencies to assess all 
costs and benefits of available regulatory alternatives and, if 
regulation is necessary, to select regulatory approaches that maximize 
net benefits (including potential economic, environmental, public 
health and safety effects, distributive impacts, and equity).\5\ The 
Executive Order 14094 entitled ``Modernizing Regulatory Review'' 
(hereinafter, the Modernizing E.O.) amends section 3(f)(1) of Executive 
Order 12866 (Regulatory Planning and Review). The amended section 3(f) 
of Executive Order 12866 defines a ``significant regulatory action'' as 
an action that is likely to result in a rule: (1) having an annual 
effect on the economy of $200 million or more in any 1 year (adjusted 
every 3 years by the Administrator of the Office of Information and 
Regulatory Affairs (OIRA) for changes in gross domestic product), or 
adversely affect in a material way the economy, a sector of the 
economy, productivity, competition, jobs, the environment, public 
health or safety, or State, local, territorial, or Tribal governments 
or communities; (2) creating a serious inconsistency or otherwise 
interfering with an action taken or planned by another agency; (3) 
materially altering the budgetary impacts of entitlement grants, user 
fees, or loan programs or the rights and obligations of recipients 
thereof; or (4) raise legal or policy issues for which centralized 
review would meaningfully further the President's priorities or the 
principles set forth in this Executive Order, as specifically 
authorized in a timely manner by the Administrator of OIRA in each 
case.
---------------------------------------------------------------------------

    \5\ While OSHA presents the following analysis under the 
requirements of Executive Orders 12866 and 13563, the agency 
ultimately cannot simply maximize net benefits due to the overriding 
legal requirements in the OSH Act.
---------------------------------------------------------------------------

    A regulatory impact analysis (RIA) must be prepared for regulatory 
actions that are significant per section 3(f)(1) ($200 million or more 
in any 1 year). OMB's OIRA has determined this rulemaking is 
significant per section 3(f)(1) as measured by the $200 million or more 
in any 1 year. Accordingly, OSHA has prepared this Preliminary Economic 
Analysis (PEA) \6\ that to the best of the agency's ability presents 
the costs and benefits of the rulemaking. OIRA has reviewed this 
proposed standard, and the agency has provided the following assessment 
of its impact.
---------------------------------------------------------------------------

    \6\ OSHA historically has referred to their regulatory impact 
analyses (RIAs) as Economic Analyses in part because performing an 
analysis of economic feasibility is a core legal function of their 
purpose. But a PEA (or Final Economic Analysis) should be understood 
as including an RIA.
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A. Market Failure and Need for Regulation

I. Introduction
    Executive Order 12866 (58 FR 51735 (September 30, 1993)) and 
Executive Order 13563 (76 FR 3821 (January 18, 2011)) direct regulatory 
agencies to assess whether, from a legal or an economic view, a Federal 
regulation is needed to the extent it is not ``required by law.'' 
Executive Order 12866 states: ``Federal agencies should promulgate only 
such regulations as are required by law, are necessary to interpret the 
law, or are made necessary by compelling public need, such as material 
failures of private markets to protect or improve the health and safety 
of the public, the environment, or the well-being of the American 
people.'' This Executive Order further requires that each agency 
``identify the problem that it intends to address (including, where 
applicable, the failures of private markets or public institutions that 
warrant new agency action)'' and instructs agencies to ``identify and 
assess available alternatives to direct regulation.'' (58 FR 51735 
(September 30, 1993)). This section addresses those issues of market 
failure and alternatives to regulation as directed by the Executive 
Order.
    OSHA is proposing a new standard for Heat Injury and Illness 
Prevention in Outdoor and Indoor Work Settings (29 CFR 1910.148) 
because the agency has preliminarily determined, based on the evidence 
in the record, that there is a compelling public need for a 
comprehensive standard addressing employees' occupational exposure to 
hazardous heat. OSHA presents the legal requirements governing this 
standard and its preliminary findings and conclusions supporting the 
proposed standard in Section II., Pertinent Legal Authority, and 
throughout other sections of the preamble.
    As detailed in Section VIII.B., Profile of Affected Industries, 
OSHA has preliminarily determined that millions of employees are 
exposed to occupational heat hazards that place them at a significant 
risk of serious injury, illness, and death. Employees exposed to heat 
suffer higher rates of non-fatal heat-related injuries and illnesses 
(HRIs) and heat-related fatalities, including heat stroke, heat 
exhaustion, heat syncope, rhabdomyolysis, heat cramps, hyponatremia, 
heat edema, and heat rash; and heat-related injuries, including falls, 
collisions, and other workplace accidents (see Section IV., Health 
Effects for additional information). OSHA estimates that the

[[Page 70803]]

proposed standard would prevent 531 heat-related fatalities (of the 
estimated 559 annual fatalities) and 16,027 HRIs per year (of the 
estimated 24,656 annual HRIs).
    These estimates have potential limitations. The parameters used to 
estimate the magnitude of underreporting of HRIs and the effectiveness 
of the proposed standard have considerable uncertainty. Furthermore, 
these estimates do not account for other expected benefits from the 
rule (e.g., reduction in indirect traumatic injuries due to heat and 
reduction in worker disutility). For additional discussion see Sections 
VIII.E.IV., Additional Unquantified Potential Benefits and VIII.E.V., 
Uncertainty in Benefits.
    OSHA has also preliminarily determined that the standard is 
technologically and economically feasible (see Section IX., 
Technological Feasibility and Section VIII.D., Economic Feasibility). 
The agency not only finds that this proposed standard is necessary and 
appropriate to ensure the safety and health of employees exposed to 
heat, as required by the OSH Act, but also demonstrates, in this 
section, that this standard corrects a market failure in which labor 
markets fail to adequately protect employee health and safety.
    Even a perfectly functioning market maximizes efficient allocation 
of goods and services at the expense of other important social values 
to which the market (as reflected in the collective actions of its 
participants) is indifferent or undervalues. In such cases, government 
intervention might be justified to address a compelling public need. 
The history and enactment of the OSH Act indicate a Congressional view 
that American markets undervalued occupational safety and health when 
it set forth the Act's protective purposes and authorized the Secretary 
of Labor to promulgate occupational safety and health standards.
    As discussed in this section, OSHA concludes there is a 
demonstrable failure of labor markets to protect employees from 
exposure to significant, unnecessary risks from heat exposure. The 
agency recognizes that many firms and governments have responded to the 
risks from heat exposure by implementing control programs for their 
employees. Information that OSHA has collected suggests that many 
employees with occupational exposure to hazardous heat currently 
receive some level of protection against heat hazards and some existing 
control programs may be as protective as the proposed standard. 
Nevertheless, the effectiveness of labor markets in providing the level 
of employee health and safety required by the OSH Act is not universal, 
as many other employers in the same sectors fail to provide their 
employees with adequate protection against heat hazards. This is 
evidenced by the documented injuries, illnesses, and deaths discussed 
throughout this preamble. Accordingly, the existence of adequate 
protections in some workplaces speaks to the feasibility of the 
standard, not necessarily to the lack of need.
    In this case, OSHA has preliminarily determined that protections 
are needed to ensure the safety and health of employees exposed to 
heat. This section is devoted to showing that markets fail with respect 
to optimal risk for occupational exposure to heat hazards. Other 
sections of this preamble address whether, given that markets fail, a 
new regulation is needed.
    The discussion below considers why labor markets, as well as 
information dissemination programs, workers' compensation systems, and 
tort liability options, each may fail to protect employees from heat 
hazards, resulting in the need for a more protective OSHA standard.
II. Labor Market Imperfections
    Under suitable conditions, a market system is economically 
efficient in the following sense: resources are allocated where they 
are most highly valued; the appropriate mix of goods and services, 
embodying the desired bundle of characteristics, is produced; and 
further improvements in the welfare of any member of society cannot be 
attained without making at least one other member worse off.
    Economic theory, supported by empirical data, posits that, in the 
labor market, employers and their potential employees bargain over the 
conditions of employment, including not only salary and other employee 
benefits, but also occupational risks to employee safety and health. 
Employers compete among themselves to attract employees. In order to 
induce potential employees to accept hazardous jobs, employers must 
offer a higher salary--termed a ``wage premium for risk'' or ``risk 
premium'' for short--to compensate for the additional job risk.\7\ 
Because employers must pay higher wages for more hazardous work, they 
have an incentive to make the workplace safer by making safety-related 
investments in equipment and training or by using more costly but safer 
work practices. According to economic theory, the operation of the 
labor market will provide the optimal level of occupational risk when 
each employer's additional cost for job safety just equals the avoided 
payout in risk premiums to employees (Lavetti, 2023). The theory 
assumes that each employer is indifferent to whether it pays the higher 
wage or pays for a safer or more healthful workplace but will opt for 
whichever costs less or improves productivity more.
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    \7\ The concept of compensating wage differentials for 
undesirable job characteristics, including occupational hazards, 
goes back to Adam Smith's The Wealth of Nations, which was 
originally published in 1776. More recent empirical investigation 
has tended to validate the core theory, with the acknowledgement of 
labor market imperfections, as otherwise noted in this section 
(e.g., Lavetti, 2023).
---------------------------------------------------------------------------

    For the labor market to function in a way that leads to optimal 
levels of occupational risk, three conditions must be satisfied. First, 
potential employees and employers must have the same, perfect 
information--that is, they must be fully informed about their workplace 
options, including job hazards, or be able to acquire such information. 
Second, participants in the labor market must directly bear all the 
costs and obtain all the benefits of their actions. In other words, 
none of the direct impacts of labor market transactions can be 
externalized to outside parties. Third, the relevant labor markets must 
be perfectly competitive, which requires a large number of employers, a 
large number of employees, and other conditions such that no individual 
economic agent is able to influence the risk-adjusted wage, and such 
that the risk-adjusted wage, net of other amenities, is equal to the 
marginal revenue associated with their output (Card, 2022).
    The discussion below examines (1) imperfect information, (2) 
externalities, and (3) imperfect competition in the labor market in 
more detail, with particular emphasis on employee exposure to heat 
hazards, as appropriate.\8\
---------------------------------------------------------------------------

    \8\ The section on workers' compensation insurance later in this 
section identifies and discusses other related market imperfections.
---------------------------------------------------------------------------

A. Imperfect Information
    As described below, imperfect information about job hazards is 
present at several levels that reinforce each other: employers 
frequently lack knowledge about workplace hazards and how to reduce 
them; employees are often unaware of the workplace risks to which they 
are exposed; and employees typically have difficulty in understanding 
the risk information they are able to obtain. Imperfect information at 
these various levels has likely

[[Page 70804]]

impeded the efficient operation of the labor market regarding workplace 
risk because employees--unaware of job hazards--do not seek, or 
receive, full compensation for the risks they bear. As a result, even 
if employers have full knowledge about the risk, their employees do 
not. If employees do not have full knowledge about the risk, employers 
have less incentive to invest in safer working conditions than they 
would in the presence of full information since wages are suppressed 
below what full knowledge by the employees would yield.
I. Lack of Employer Information
    In the absence of regulation, employers may lack economic 
incentives to optimally identify the safety and health risks that their 
employees face.\9\ Furthermore, employers have an economic incentive to 
withhold the information they do possess about job hazards from their 
employees, whose response would be to demand safe working conditions or 
higher wages to compensate for the risk. Relatedly, in the absence of 
regulation, employers, as well as third parties, may have fewer 
incentives to develop new technological solutions to protect employees 
on the job.\10\
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    \9\ Other private parties may lack sufficient incentives to 
invest resources to collect and analyze occupational risk data due 
to the public-good nature of the information. See Ashford and 
Caldart (1996).
    \10\ For evidence of regulatory stimuli inducing innovations to 
improve employee health and safety, see, for example, Ashford et al. 
(1985), as well as more recent evidence from OSHA's regulatory 
reviews under section 610 of the RFA (5 U.S.C. 610).
---------------------------------------------------------------------------

    This suggests that, without regulation, and the incentives that 
come with it, many employers are unlikely to make themselves aware of 
the magnitude of heat-related safety and health risks in the workplace 
or of the availability of effective ways of ameliorating or eliminating 
these risks. OSHA believes that requiring employers to monitor heat 
conditions will help to alleviate situations in which employers and/or 
employees may not realize situations when heat becomes hazardous.
II. Lack of Employee Information About Health Hazards
    Markets cannot adequately address the risks of occupational heat 
exposure if employees and employers are unaware of the changes in risk 
brought about by an employer's actions or inaction. Even if employees 
and employers are aware of a risk, the employer may have limited 
economic motivation to install controls unless the employees are able 
to accurately assess the effects of those controls on their 
occupational risks.
    Accordingly, even if employees have a general understanding that 
they are at increased risk of injury or illness from occupational 
exposure to heat, it is unrealistic to expect, absent mandatory 
regulatory requirements, that they know the precise risks associated 
with different exposure levels or the exposures they are experiencing, 
much less that they can use that knowledge to negotiate a significant 
reduction in exposures and other protections or (if more desirable) 
trade it for greater hazard pay.
    Both experimental studies and observed market behavior suggest that 
individuals have considerable difficulty rationally processing 
information about low-probability, high-consequence events such as 
occupational fatalities and long-term disabilities.\11\ For example, 
many individuals may not be able to comprehend or rationally act on 
risk information when it is presented, as risk analysis often is, in 
mathematical terms--a 1/1,000 versus a 1/10,000 versus a 1/100,000 
annual risk of death from occupational causes.
---------------------------------------------------------------------------

    \11\ The literature documenting risk perception problems is 
extensive. See the classic work of Tversky and Kahneman (1974). For 
a recent summary of risk perception problems and their causes 
(Thaler and Sunstein, 2009).
---------------------------------------------------------------------------

    Of course, in the abstract, many of the problems that employers and 
employees face in obtaining and processing occupational risk can lead 
employees to overestimate as well as underestimate the risk. However, 
some of the impacts of heat exposure may be sufficiently infrequent, 
unfamiliar, or unobvious that many employees (and at least some 
employers) may be completely unaware of the risk, and therefore will 
underestimate it.
    In addition, for markets to optimally address this risk, employees 
need to be aware of the changes in risk brought about by an employer's 
actions. Even if employees are aware of a risk, the employer may have 
limited economic motivation to install controls or implement protective 
measures unless the employees are able to accurately assess the effects 
of those controls or measures on their occupational risks. Furthermore, 
there is substantial evidence that most individuals are unrealistically 
optimistic, even in high-stakes, high-risk situations and even if they 
are aware of the statistical risks (Thaler and Sunstein, 2009). 
Although the agency lacks specific evidence on the effect of these 
attitudes on assessing occupational safety and health risks, this 
suggests that some employees underestimate their own risk of work-
related injury or illness and, therefore, even in situations where they 
have the bargaining power to do so, may not bargain for or receive 
adequate compensation for bearing those risks. Finally, the difficulty 
that employees have in distinguishing marginal differences in risk at 
alternative worksites, both within an industry and across industries, 
creates a disincentive for employers to incur the costs of reducing 
workplace risk.
B. Externalities
    Externalities arise when an economic transaction generates direct 
positive or negative spillover effects on third parties not involved in 
the transaction. The resulting spillover effect, which leads to a 
divergence between private and social costs, undermines the efficient 
allocation of resources in the market because the market is imparting 
inaccurate cost and price signals to the transacting parties. Applied 
to the labor market, when costs are externalized, they are not 
reflected in the decisions that employers and their potential employees 
make--leading to allocative distortions in that market.
    Negative externalities exist in the labor market because many of 
the costs of occupational injury and illness are borne by parties other 
than individual employers or employees. The major source of these 
negative externalities is the occupational injury or illness cost that 
workers' compensation does not cover.\12\ Employees and their employers 
often bear only a portion of these costs. Outside of workers' 
compensation, employees incapacitated by an occupational injury or 
illness and their families often receive health care, rehabilitation, 
retraining, direct income maintenance, or life insurance benefits, much 
of which are paid for by society through Social Security and other 
social insurance and social welfare programs.\13\
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    \12\ Workers' compensation is discussed separately later in this 
section. As described there, in many cases (particularly for smaller 
firms), the premiums that an individual employer pays for workers' 
compensation are only loosely related, or unrelated, to the 
occupational risks that that employer's employees bear. In addition, 
workers' compensation does not cover chronic occupational diseases 
in most instances. For that reason, negative externalities tend to 
be a more significant issue in the case of occupational exposures 
that result in diseases.
    \13\ In addition, many occupational injuries and most 
occupational illnesses are not processed through the workers' 
compensation system at all. In these instances, employees receive 
care from their own private physician rather than from their 
employer's physician.
---------------------------------------------------------------------------

    Furthermore, substantial portions of the medical care system in the 
United States are heavily subsidized by the

[[Page 70805]]

government so that part of the medical cost of treating injured or ill 
employees is paid for by the rest of society (Nichols and Zeckhauser, 
1977). To the extent that employers and employees do not bear the full 
costs of occupational injury and illness, they will ignore these 
externalized costs in their labor market negotiations. The result may 
be an inefficiently high level of occupational risk.
C. Imperfect Competition
    In the idealized labor market, the actions of large numbers of 
buyers and sellers of labor services establish the market-clearing, 
risk-compensated wage, so that individual employers and employees 
effectively take that wage as given. However, the labor market is not 
one market, but many markets differentiated by location, occupation, 
and other factors; entrants in the labor market face search frictions 
because of limited information on employment options; and, furthermore, 
in wage negotiations with their own employees, employers are typically 
in an advantageous position relative to all other potential employers 
(e.g., Card, 2022). In these situations, discussed below, employers may 
have sufficient power to influence or to determine the wage their 
employees receive. This may undermine the conditions necessary for 
perfect competition and can result in inadequate compensation for 
employees exposed to workplace hazards. Significant unemployment 
levels, local or national, may also undermine the conditions necessary 
for adequate compensation for exposure to workplace hazards (Hirsch et 
al., 2018).
    Beyond the classic--but relatively rare--example of a town 
dominated by a single company, there is significant evidence that some 
employers throughout the economy are not wage-takers but, rather, face 
upward-sloping labor supply curves and enjoy some market power in 
setting wages and other conditions of employment.\14\ An important 
source of this phenomenon is the cost of a job search and the 
employer's relative advantage, from size and economies of scale, in 
acquiring labor market information.\15\ Another potentially noteworthy 
problem in the labor market is that, contrary to the model of perfect 
competition, employees with jobs cannot without cost quit and obtain a 
similar job at the same wage with another employer. Employees leaving 
their current job may be confronted with the expense and time 
requirements of a job search, the expense associated with relocating to 
take advantage of better employment opportunities, the loss of firm-
specific human capital (i.e., firm-specific skills and knowledge that 
the employee possesses \16\), the cost and difficulty of upgrading job 
skills, and the risk of a prolonged period of unemployment. Finally, 
employers derive market power from the fact that a portion of the 
compensation their employees receive is not transferable to other jobs. 
Examples include job-specific training and associated compensation, 
seniority rights and associated benefits, and investments in a pension 
plan.
---------------------------------------------------------------------------

    \14\ See Borjas (2000), Ashenfelter et al. (2010), and Boal and 
Ransom (1997). The term ``monopsony'' power or ``oligopsony'' power 
are sometimes applied to this situation.
    \15\ See Borjas (2000). As supplemental authorities, Weil (2014) 
presents theory and evidence both in support of this proposition and 
to show that, in many situations, larger firms have more market 
power than smaller firms, while Boal and Ransom (1997) note that the 
persistent wage dispersion observed in labor markets is a central 
feature of equilibrium search models.
    \16\ MacLeod and Nakavachara (2007) note the correlation between 
firm-specific skills and relatively high income.
---------------------------------------------------------------------------

    Under the conditions described above, employers would not have to 
take the market-clearing wage as given but could offer a lower wage 
than would be observed in a perfectly competitive market,\17\ including 
less than full compensation for workplace health and safety risks. As a 
result, relative to the idealized competitive labor market, employers 
would have less incentive to invest in workplace safety. In any event, 
for reasons already discussed, an idealized wage premium is not an 
adequate substitute for a workplace that puts a premium on health and 
safety.
---------------------------------------------------------------------------

    \17\ For a graphical demonstration that an employer with 
monopsony power will pay less than the competitive market wage, see 
Borjas (2000).
---------------------------------------------------------------------------

III. Non-Market and Quasi-Market Alternatives
    The following discussion considers whether non-market and quasi-
market alternatives to the proposed standard would be capable of 
protecting employees from heat hazards. The alternatives under 
consideration are information dissemination programs, workers' 
compensation systems, and tort liability options.
A. Information Dissemination Programs
    One alternative to OSHA's proposed standard could be the 
dissemination of information, either voluntarily or through compliance 
with a targeted mandatory information rule, akin to OSHA's Hazard 
Communication standard (29 CFR 1910.1200), which would provide more 
information about the safety and health risks associated with exposure 
to environmental heat. Better informed potential employees could more 
accurately assess the occupational risks associated with different 
jobs, thereby facilitating, through labor market transactions, higher 
risk premiums for more hazardous work and inducing employers to make 
the workplace less hazardous. The proposed standard recognizes the link 
between the dissemination of information and workplace risks by 
requiring that employees exposed to heat be provided with information 
and training about the risks they encounter and ways to mitigate those 
risks. There are several reasons, however, why reliance on information 
dissemination programs alone would not yield the level of employee 
protection achievable through the proposed standard, which incorporates 
hazard communication as part of a comprehensive approach designed to 
control the hazard in addition to providing for the disclosure of 
information about it.
    First, in the case of voluntary information dissemination programs, 
absent a regulation, there may be significant economic incentives, for 
all the reasons discussed in section VIII.A.II. above, for the employer 
not to gather relevant exposure data or distribute occupational risk 
information so that the employees would not change jobs or demand 
higher wages to compensate for their newly identified occupational 
risks.
    Second, even if employees were better informed about workplace 
risks and hazards, all of the defects in the functioning of the private 
labor market previously discussed--the limited ability of employees to 
evaluate risk information, externalities, and imperfect competition--
would still apply. Because of the existence of these defects, better 
information alone would not lead to wage premiums for risk that would 
incentivize employers to make workplaces safer, in accordance with 
compensating differentials theory (Lavetti, 2023). Regardless, as 
mentioned above in section VIII.A.I., even the level of employee safety 
and health attained by the wage premium under efficient markets may be 
lower than the level justified by other important social values that 
efficient markets may undervalue. Finally, as discussed in Section 
VIII.E., Benefits, a number of additional safety provisions under the 
proposed standard would complement information and training provided by 
other regulatory vehicles.
    Thus, while improved access to information about heat-related 
hazards can provide for more rational decision-making in the private 
labor market,

[[Page 70806]]

OSHA concludes that information dissemination programs would not, by 
themselves, produce an adequate level of employee protection.
B. Workers' Compensation Systems
    Another theoretical alternative to OSHA regulation could be to 
determine that no standard is needed because State workers' 
compensation programs augment the workings of the labor market to limit 
occupational risks to employee safety and health. After all, one of the 
objectives of the workers' compensation system is to shift the costs of 
occupational injury and illness from employees to employers in order to 
induce employers to improve working conditions. Two other objectives 
relevant to this discussion are to provide fair and prompt compensation 
to employees for medical costs and lost wages resulting from workplace 
injury and illness and, through the risk-spreading features of the 
workers' compensation insurance pool, to prevent individual employers 
from suffering a catastrophic financial loss (Ashford, 2007).
    OSHA identifies two primary reasons, discussed below, why the 
workers' compensation system has fallen short of the goal of shifting 
to employers the costs of workplace injury and illness--including, in 
particular, the costs of employee exposure to heat-related hazards. As 
a result, OSHA concludes that workers' compensation programs alone do 
not adequately protect employees.
I. Limitations on Payouts
    The first reason that employers do not fully pay the costs of work-
related injuries and illnesses under the workers' compensation system 
is that, even for those claims that are accepted into the system, 
States have imposed significant limitations on payouts. Depending on 
the State, these limitations and restrictions include:
     Caps on wage replacement based on the average wage in the 
State rather than the injured employee's actual wage;
     Restrictions on which medical care services are 
compensated and the amount of that compensation;
     No compensation for non-pecuniary losses, such as pain and 
suffering or impairment not directly related to earning power;
     Either no, or limited, cost-of-living increases;
     Restrictions on permanent, partial, and total disability 
benefits, either by specifying a maximum number of weeks for which 
benefits can be paid or by imposing an absolute ceiling on dollar 
payouts; and
     A low absolute ceiling on death benefits.
II. A Divergence Between Workers' Compensation Premiums and Workplace 
Risk
    The second reason workers' compensation does not adequately shift 
the costs of work-related injuries and illnesses to employers is that 
the risk-spreading objective of workers' compensation conflicts with, 
and ultimately helps to undermine, the cost-internalization 
objective.\18\ For the 99 percent of employers who rely on workers' 
compensation insurance,\19\ the payment of premiums represents their 
primary cost for occupational injuries and illnesses, such as heat-
related injuries and illnesses. However, the mechanism for determining 
an employer's workers' compensation insurance premium typically fails 
to reflect the actual occupational risk present in that employer's 
workplace.
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    \18\ Recall from the earlier discussion of externalities that 
the failure to internalize costs leads to allocative distortions and 
inefficiencies in the market.
    \19\ Only the largest firms, constituting approximately 1 
percent of employers and representing approximately 15 percent of 
employees, are self-insured. These individual firms accomplish risk-
spreading as a result of the large number of employees they cover 
(Ashford, 2007). From 2000 to 2020, the share of Workers' 
Compensation Benefits paid by self-insured employers rose from 22.0 
percent to 24.7 percent (Murphy and Wolf, 2022).
---------------------------------------------------------------------------

    Approximately 85 percent of employers have their premiums set based 
on a ``class rating,'' which is based on industry illness and injury 
history. Employers in this class are typically the smallest firms and 
represent only about 15 percent of employees (Ashford, 2007). Small 
firms are often ineligible for experience rating because of 
insufficient claims history or because of a high year-to-year variance 
in their claim rates. These firms are granted rate reductions only if 
the experience of the entire class improves. The remaining 14 percent 
of employers, larger firms representing approximately 70 percent of 
employees, have their premiums set based on a combination of ``class 
rating'' and ``experience rating,'' which adjusts the class rating to 
reflect a firm's individual claims experience. A firm's experience 
rating is generally based on the history of workers' compensation 
payments to employees injured at that firm's workplace, not on the 
quality of the firm's overall employee protection program or safety and 
health record. Thus, for example, the existence of circumstances that 
may lead to catastrophic future losses are not included in an 
experience rating--only actual past losses are included.\20\ Insurance 
companies do have the right to refuse to provide workers' compensation 
insurance to an employer--and frequently exercise that right based on 
their inspections and evaluations of a firm's health and safety 
practices. However, almost all States have assigned risk pools that 
insist that any firm that cannot obtain workers' compensation policies 
from any insurer must be provided workers' compensation insurance at a 
State-mandated rate that reflects a combination of class and experience 
rating. Workers' compensation insurance does protect individual 
employers against a catastrophic financial loss due to work-related 
injury or illness claims. As a result of risk spreading, however, 
employers' efforts to reduce the incidence of occupational injuries and 
illnesses are not fully reflected in reduced workers' compensation 
premiums. Conversely, employers who devote fewer resources to promoting 
employee safety and health may not incur commensurately higher workers' 
compensation costs. This creates a type of moral hazard, in that the 
presence of risk spreading in workers' compensation insurance may 
induce employers to make fewer investments in equipment and training to 
reduce the risk of workplace injuries and illnesses.
---------------------------------------------------------------------------

    \20\ In order to spread risks in an efficient manner, it is 
critical that insurers have adequate information to set individual 
premiums that reflect each individual employer's risks. As the 
preceding discussion has made clear, by and large, they do not. In 
that sense, insurers can be added to employers and employees as 
possessing imperfect information about job hazards.
---------------------------------------------------------------------------

    In short, the premiums most individual employers pay for workers' 
compensation insurance coverage do not reflect the actual cost burden 
those employers impose on the worker's compensation system. 
Consequently, employers considering measures to lower the incidence of 
workplace injuries and illnesses can expect to receive a less-than-
commensurate reduction in workers' compensation premiums. Thus, for all 
the reasons discussed above, the workers' compensation system does not 
provide adequate incentives to employers to control occupational risks 
to worker safety and health.
C. Tort Liability Options
    Another alternative to OSHA regulation could be for employees to 
use the tort system to seek redress for work-related injuries and 
illnesses, including heat-related ones.\21\ A tort is a civil

[[Page 70807]]

wrong (other than breach of contract) for which the courts can provide 
a remedy by awarding damages. The application of the tort system to 
occupational injury and illness would allow employees to sue their 
employer, or other responsible parties where applicable (e.g., ``third 
parties'' such as suppliers of hazardous material or equipment used in 
the workplace) to recover damages. In theory, the tort system could 
shift the liability for the direct costs of occupational injury and 
illness from the employee to the employer or to other responsible 
parties. In turn, the employer or third parties would be induced to 
improve employee safety and health.
---------------------------------------------------------------------------

    \21\ The OSH Act does not provide a private right of action that 
would allow affected workers to sue their employers for safety 
hazards subject to the Act (see Am. Fed. of Gov. Employees, AFL-CIO 
v. Rumsfeld, 321 F.3d 139, 143-44 (DC Cir. 2003)).
---------------------------------------------------------------------------

    With limited exceptions, the tort system has not been a viable 
alternative to occupational safety and health regulation. In addition, 
State statutes make workers' compensation the ``exclusive remedy'' for 
work-related injuries and illnesses. Workers' compensation is 
essentially a type of no-fault insurance. In return for employers' 
willingness to provide, through workers' compensation, timely wage-loss 
and medical coverage for workers' job-related injuries and illnesses, 
regardless of fault, employees are barred from suing their employers 
for damages, except in cases of intentional harm or, in some States, 
gross negligence (Ashford and Caldart, 1996). Even in cases of gross 
negligence where it is possible for employees to sue, establishing 
gross negligence in these incidences is complicated by heat conditions 
as these conditions may be temporary and localized, and not necessarily 
measured at the time of incident. Practically speaking, in most cases, 
workers' compensation is the exclusive legal remedy available to 
employees for workplace injuries and illnesses.
    Employees are thus generally barred from suing their own employers 
in tort for occupational injuries or illnesses but may attempt to 
recover damages for work-related injuries and illnesses, where 
applicable, from third parties through the tort system. However, it is 
unlikely that a third party could be successfully sued for workplace 
exposure to hazardous heat since there is no third party responsible 
for exposing employees to dangerous conditions in these circumstances. 
This means that even this inadequate remedy would be unavailable to 
employees injured from heat exposure.
    In sum, the use of the tort system as an alternative to regulation 
is severely limited because of the ``exclusive remedy'' provisions in 
workers' compensation statutes; because of the various legal and 
practical difficulties in seeking recovery from responsible third 
parties or the lack of a responsible third party altogether; and 
because of the substantial costs associated with a tort action. The 
tort system, therefore, does not adequately protect employees from 
exposure to hazards in the workplace.
IV. Summary
    OSHA's primary reasons for proposing this standard are based on the 
requirements of the OSH Act, which are discussed in Section II., 
Pertinent Legal Authority. As shown in the preamble to the proposed 
standard and this PEA, OSHA has determined that employees in many 
industries are exposed to safety and health hazards from exposure to 
environmental and process heat in the workplace. This section has shown 
that labor markets--even when augmented by information dissemination 
programs, workers' compensation systems, and tort liability options--
still operate at a level of risk for these employees that is higher 
than socially optimal due to a lack of information about safety and 
health risks, the presence of externalities or imperfect competition, 
and other factors discussed above.

B. Profile of Affected Industries

I. Introduction
    This section presents a profile of the entities and employees for 
all industries that would be affected by OSHA's proposed standard for 
Heat Injury and Illness Prevention in Outdoor and Indoor Work Settings. 
OSHA first outlines all industries that would be subject to the 
proposed standard. Next, OSHA summarizes the number of entities and 
employees that would be exempt from this proposed standard based on 
coverage under existing standards, jurisdiction of local or State 
government entities, or based on one of the exemptions in paragraph 
(a)(2) of this proposed standard. Lastly, OSHA provides summary 
statistics for the affected entities,\22\ including the number of 
affected entities and the number of affected employees. This 
information is provided for each industry (1) in total, (2) for small 
entities as defined by the Regulatory Flexibility Act (RFA) and by the 
Small Business Administration (SBA), and (3) for very small entities 
with fewer than 20 employees.
---------------------------------------------------------------------------

    \22\ Spreadsheet detailing all calculations discussed in this 
analysis are available in Analytical Support for OSHA's Preliminary 
Economic Analysis for the Heat Injury and Illness Prevention (OSHA, 
2024c).
---------------------------------------------------------------------------

II. Potentially Affected Industries and Employees
    This section characterizes the industries and employees that are 
likely to be affected by the proposed standard.
A. Potentially Affected Industries
    OSHA broadly characterizes industries that are potentially within 
the scope of the regulatory framework as core industries \23\ and all 
other covered industries. OSHA considers core industries to be those 
industries where employees have the most exposure to heat-related 
hazards, such as through exposure to high outdoor temperatures, radiant 
heat sources, or insufficient temperature control or ventilation in 
indoor work settings. Core industries include:
---------------------------------------------------------------------------

    \23\ To identify core industries, OSHA reviewed multiple 
sources. The agency reviewed its OSHA Information System (OIS) 
database to identify industries with fatal and non-fatal heat-
related injuries and illnesses. In addition, OSHA identified 
occupations with the most exposure to heat-related hazards by 
analyzing (1) occupational information on outdoor work settings from 
the Occupational Information Network (O*NET) and (2) occupation-
level data from the Occupational Requirements Survey (ORS) on 
exposure to process heat. Occupations flagged by those two data 
sources were then mapped to detailed 2012 North American Industry 
Classification System (NAICS) codes using the Occupational 
Employment and Wage Statistics (OEWS). Finally, OSHA evaluated 
industries that were included in OSHA's National Emphasis Program 
for Outdoor and Indoor Heat Related Hazards, ANPRM comments, and 
stakeholder comments.
---------------------------------------------------------------------------

     Agriculture, Forestry, and Fishing;
     Building Materials and Equipment Suppliers;
     Commercial Kitchens;
     Construction;
     Drycleaning and Commercial Laundries;
     Landscaping and Facilities Support;
     Maintenance and Repair;
     Manufacturing;
     Oil and Gas;
     Postal and Delivery Services;
     Recreation and Amusement;
     Sanitation and Waste Removal;
     Telecommunications;
     Temporary Help Services;
     Transportation;
     Utilities; and
     Warehousing.
    While employee exposure to heat-related hazards is expected to be 
more frequent in the core industries, employees in all other industries 
within the agency's jurisdiction have the potential to experience 
occupational heat-related hazards and would also be covered by this 
proposed standard, with the exception of employers that meet

[[Page 70808]]

the criteria for one of the scope exemptions in paragraph (a)(2) 
(discussed in detail in section VII.A., and below). For example, there 
are certain jobs, such as maintenance and landscaping occupations, 
regardless of the industry in which they are performed, that require 
physical exertion which may increase the risk of heat stress.
    Most of the economic data on number of firms, number of 
establishments, employment,\24\ and annual receipts are sourced from 
the Census Bureau's Statistics of U.S. Businesses (SUSB) 2017 dataset 
(Census Bureau, 2021a). SUSB \25\ presents these data \26\ by North 
American Industry Classification System (NAICS) code, employee class 
size, and State. Unlike most other standards that OSHA proposes, costs 
will differ not just by industry, but also by the geographical location 
of workplaces due to variations in environmental conditions. See 
discussion of geographic location later in this section.
---------------------------------------------------------------------------

    \24\ For some industry-state combinations, the total employment 
in the SUSB data was less than the number of establishments. For 
these cases, OSHA adjusted total employment so that total employment 
is equal to the number of establishments.
    \25\ SUSB covers most NAICS industries excluding Crop and Animal 
Production (NAICS 111, 112); Rail Transportation (NAICS 482); Postal 
Service (NAICS 491); Pension, Health, Welfare, and Other Insurance 
Funds (NAICS 525110, 525120, 525190); Trusts, Estates, and Agency 
Accounts (NAICS 525920); Offices of Notaries (NAICS 541120); Private 
Households (NAICS 814); and Public Administration (NAICS 92). SUSB 
also excludes most establishments reporting government employees. 
(https://www.census.gov/programs-surveys/susb/about.html) To the 
extent that there are some establishments reporting government 
employees that are also captured in Government Units Survey or the 
Census of Governments database, OSHA's estimates may overstate the 
number of covered employees and establishments.
    \26\ These annual SUSB figures are based on the counts of these 
variables during the week of March 12th of the reference year.
---------------------------------------------------------------------------

    The SUSB glossary (Census Bureau, 2024b) defines the following 
terms as follows. Establishments are defined as an economic unit, 
typically a single physical location where business is conducted, 
services are performed, or industrial operations occur. Firms are legal 
business organizations and may consist of a single establishment or 
multiple establishments under common ownership or control. Employment 
is a measure of paid full- and part-time employees, including employees 
on paid sick leave, holidays, and vacations.\27\ Annual receipts are 
defined as operating revenue for goods and services summed by industry, 
net of taxes collected from customers or clients.
---------------------------------------------------------------------------

    \27\ Employment includes salaried officers and executives and 
excludes sole proprietors and partners of unincorporated businesses.
---------------------------------------------------------------------------

    There are instances where estimates are left undisclosed in the 
SUSB dataset because there are only a few companies in a certain 
industry in a given State. Relying solely on SUSB datafiles would 
result in an undercount of the potentially affected employers and 
employees due to the undisclosed data. For this reason, OSHA attempted 
to fill in these data gaps in these undisclosed industries with 
alternative data sources. These industries with data gaps are listed 
below, along with the alternative sources and methods for estimating 
the number of firms, number of establishments, employment, and annual 
receipts. OSHA welcomes additional data sources or alternative 
methodologies to fill these data gaps.
    Agriculture: Most agricultural industries are not included in the 
SUSB dataset,\28\ so OSHA used the Department of Agriculture's 2017 
Census of Agriculture (USDA, 2019) to derive estimates of the necessary 
industry profile information. OSHA used the count of farms from chapter 
2, table 44 ``Farms by North American Industry Classification System'' 
to represent the number of establishments for each agricultural 
industry. OSHA assumed that the number of firms is equal to the number 
of establishments.\29\ OSHA used industry-level estimates of 
``workers'' on hired labor farms and ``total sales'' from chapter 1, 
table 75 ``Summary by North American Industry Classification System'' 
to represent employment counts and annual receipts, respectively. OSHA 
welcomes feedback on alternative sources, estimation methods, and 
assumptions for estimations of firms, establishments, and employment in 
the agricultural sector.
---------------------------------------------------------------------------

    \28\ The NAICS industries that were estimated using this method 
are Oilseed and Grain Farming (111100), Vegetable and Melon Farming 
(111200), Fruit and Nut Tree Farming (111300), Greenhouse, Nursery, 
and Floriculture (111400), Other Crop Farming (111900), Cattle Ranch 
and Farming (112100), Hog and Pig Farming (112200), Poultry and Egg 
Production (112300), Sheep and Goat Farming (112400), Aquaculture 
(112500), and Other Animal Production (112900).
    \29\ Family farms account for 96 percent of all U.S. farms 
(https://www.nass.usda.gov/Newsroom/archive/2021/01-22-2021.php).
---------------------------------------------------------------------------

    Local Government \30\: The SUSB dataset excludes most government 
entities, including local governments. OSHA primarily relied on data 
from three alternative sources for local government estimates. To 
estimate the number of government entities, number of establishments, 
and employment, OSHA used the county-, city-, and town-level data from 
the Census Bureau's Government Units Survey (GUS) for 2022 (Census 
Bureau, 2023d) by State to estimate the number of firms per State. 
Then, OSHA assumed that each entity represented one firm which was 
equal to one establishment.\31\ Since the GUS data do not include 
estimates for local government employment by State, OSHA used the 2022 
Census of Governments' Survey of Public Employment & Payroll local 
employment data (Census Bureau, 2023b) to develop these estimates. OSHA 
distributed these local employees based on a ratio of local government 
employees to population served within each State as provided in the 
GUS, resulting in an estimate of employment for each local government 
entity within the GUS. These estimates were summed to the State level 
for OSHA's analysis.
---------------------------------------------------------------------------

    \30\ In this analysis, OSHA only considered government entities 
in OSHA state plan states. See section VIII.B.III.H. later in this 
section for a discussion of exemptions based on OSHA jurisdiction.
    \31\ To the extent that there are multiple establishments for a 
single local government entity, this method underestimates the 
number of establishments.
---------------------------------------------------------------------------

    OSHA's estimate for annual receipts per government entity also 
required two steps. First, OSHA estimated the average annual receipts 
per resident by State. The estimate was equal to the ratio of total 
local government receipts in the datasets found in the Census Bureau's 
2021 Annual Survey of State and Local Government Finances (Census 
Bureau, 2023a) to the total population served in the GUS dataset. Then, 
OSHA multiplied the population associated with each government entity 
captured in the GUS with the ratio from step one to arrive at an 
estimate of total annual receipts per government entity. OSHA again 
aggregated these estimates to the State level for this analysis.
    OSHA welcomes feedback on alternative sources, estimation methods, 
and assumptions for estimations of firms, establishments, and 
employment in local governments.
    State Government: State government entities are excluded from the 
SUSB dataset, so OSHA relied on two alternative data sources for counts 
of firms and establishments, employment, and annual receipts. OSHA 
assumed that each State government is equal to one firm and that each 
State government firm is equal to one State government 
establishment.\32\
---------------------------------------------------------------------------

    \32\ To the extent that state governments have multiple 
establishments, this method underestimates the number of 
establishments.
---------------------------------------------------------------------------

    OSHA used the total State government full-time and part-time 
employment data from the 2022 Census of Governments' Survey of Public

[[Page 70809]]

Employment & Payroll (Census Bureau, 2023b) to represent State 
government employment estimates. OSHA used the State government 
revenues estimated in the Census Bureau's 2021 Annual Survey of State 
and Local Government Finances (Census Bureau, 2023a) to estimate annual 
receipts for State governments.
    OSHA welcomes feedback on alternative sources, estimation methods, 
and assumptions for estimations of firms, establishments, and 
employment in State governments.
    Rail Transportation,\33\ Postal Service, and Insurance and Employee 
Benefit Funds: SUSB data relied upon for the majority of the estimates 
in this industry profile do not include estimates for a small subset of 
non-agricultural industries: Rail Transportation (NAICS 4821), Postal 
and Delivery Services (NAICS 4911), and Insurance and Employment 
Benefit Funds (NAICS 5251). The economic data estimates for these three 
industries were derived from the Quarterly Census of Employment and 
Wages (QCEW) collected by the Bureau of Labor Statistics (BLS). OSHA 
used industry-level establishment and employment counts by State from 
the 2022 QCEW dataset (BLS, 2023f). OSHA assumed that each 
establishment was also a unique firm,\34\ thus each firm equals one 
establishment. While the QCEW does not present revenue data, it does 
include total annual wages by industry and State. OSHA used the ratio 
of receipts to wages from the SUSB dataset for each State to convert 
the QCEW wage data into annual receipts by industry and State.
---------------------------------------------------------------------------

    \33\ The Federal Railroad Administration (FRA) has promulgated 
regulations requiring the use of environmental controls to address 
heat hazards in three specific, limited contexts: non-steam-powered 
locomotives purchased or remanufactured after June 8, 2012 (49 CFR 
229.119(g)), camp cars (49 CFR 228.313(c)), and certain on-track 
roadway maintenance machines (49 CFR 214.505(a)). OSHA's standard 
would apply to the working conditions of railroad employees in all 
other contexts, including within trains and machinery not covered by 
these regulations and during all outdoor work.
    \34\ To the extent that there are multiple establishments per 
firm, this will lead to an overestimate. OSHA welcomes feedback on 
this assumption and information on alternative data sources for the 
number of firms in these industries.
---------------------------------------------------------------------------

    OSHA welcomes additional data sources or alternative methodologies 
to fill data gaps in the SUSB data for industries including 
agriculture, local and State governments. The agency is particularly 
interested in data and information on the number of firms, 
establishments, and employment. OSHA has assumed that one establishment 
is equal to one firm in industries where data on this parameter are not 
available including in governments, agriculture, postal services, and 
rail transportation. The agency welcomes comment on this approach and 
suggestions for alternative approaches.
B. States and Geographic Regions.
    For this PEA, OSHA categorized States into geographic regions based 
on the National Weather Service (NWS) regions.\35\ Table VIII.B.1. 
presents the grouping of States into these regions.
---------------------------------------------------------------------------

    \35\ In the NWS groupings, three states were divided between two 
regions: Georgia (Eastern and Southern), Kentucky (Central and 
Eastern), and Wyoming (Central and Western). OSHA assigned these 
states to a single region, with Georgia assigned to the Southern 
region, Kentucky to the Central region, and Wyoming to the Western 
region.

                                  Table VIII.B.1--States and Geographic Regions
----------------------------------------------------------------------------------------------------------------
     Alaskan            Central            Eastern            Pacific            Southern           Western
----------------------------------------------------------------------------------------------------------------
Alaska             Colorado           Connecticut        American Samoa     Alabama            Arizona
                   Iowa               Delaware           Guam               Arkansas           California
                   Illinois           District of        Hawaii             Florida            Idaho
                                       Columbia
                   Indiana            Maine              Northern Mariana   Georgia            Montana
                   Kansas             Maryland            Islands           Louisiana          Nevada
                   Kentucky           Massachusetts      .................  Mississippi        Oregon
                   Michigan           New Hampshire      .................  New Mexico         Utah
                   Minnesota          New Jersey         .................  Oklahoma           Washington
                   Missouri           New York           .................  Puerto Rico        Wyoming
                   North Dakota       North Carolina     .................  Tennessee          .................
                   Nebraska           Ohio               .................  Texas              .................
                   South Dakota       Pennsylvania       .................  U.S. Virgin        .................
                                                                             Islands
                   Wisconsin          Rhode Island       .................  .................  .................
                   .................  South Carolina     .................  .................  .................
                   .................  Vermont            .................  .................  .................
                   .................  Virginia           .................  .................  .................
                   .................  West Virginia      .................  .................  .................
----------------------------------------------------------------------------------------------------------------
Source: NWS, 2024b.

C. Potentially Affected Employees Based on Work Conditions
    OSHA estimated the number of potentially affected employees across 
all affected industries based on their work conditions. To do so, OSHA 
used a combination of O*NET, Occupational Requirement Survey (ORS), and 
Occupational Employment and Wage Statistics (OEWS) program data. 
Employment is characterized using the Standard Occupational 
Classification (SOC) detailed occupations (i.e., six-digit SOC code).
    O*NET (O*NET, 2023) provides data on the percent of employees in a 
given occupation that work in certain climatic work conditions for 
specified frequencies.\36\ The climatic work conditions that OSHA 
evaluated in this analysis are (1) Indoors, Environmentally Controlled; 
(2) Indoors, Not Environmentally Controlled; (3) Outdoors, Exposed to 
Weather; and (4) Outdoors, Under Cover. For modeling purposes, OSHA 
mapped the O*NET frequency categories (O*NET, 2023) to number and 
percentages of work days worked in certain climatic work conditions, as 
shown in table VIII.B.2. For the purposes of this analysis, OSHA 
assumes that employees in work conditions (2), (3), and (4) are in-
scope of the proposed standard unless they meet exemptions discussed 
later.
---------------------------------------------------------------------------

    \36\ These frequency categories are defined as: (1) ``Never;'' 
(2) ``Once a year or more but not every month;'' (3) ``Once a month 
or more but not every week;'' (4) ``Once a week or more but not 
every day;'' (5) ``Every day.''

[[Page 70810]]



                             Table VIII.B.2--Frequency of Work in Certain Conditions
----------------------------------------------------------------------------------------------------------------
                                                                                                   Estimated
           Category No.               O*NET frequency    Minimum number of  Maximum number of    percentage of
                                       category name     days for category  days for category       days \a\
----------------------------------------------------------------------------------------------------------------
1................................  Never...............                  0                  0                  0
2................................  Less than Monthly...                  1                <12               2.60
3................................  Less than Weekly....                 12                <50              12.40
4................................  Less than Daily.....                 50               <250                 60
5................................  Every Day...........                250                250                100
----------------------------------------------------------------------------------------------------------------
Sources: Frequency categories are defined by O*NET Online Resource Center (O*NET, 2023).
Estimated percentage of days are based on methodology from Park et al. (2021).
\a\ These percentages are based on a 250-day work year.

    There are multiple SOC occupation codes for which the O*NET dataset 
does not provide the percentages of employees in an occupation for each 
of these brackets. In these instances, OSHA used the average frequency 
of work in these conditions from similar SOC occupation codes as 
representative of the missing SOC occupation code to estimate the 
frequency of work in these conditions for occupations with missing 
data.
    Using the percentages of each occupation within the frequency 
categories and the estimated percentages of days worked by category 
presented in the table above, OSHA estimated the percentage of 
employees that would be working regularly in certain climatic work 
conditions by occupation. OSHA then multiplied these percentages by the 
percentage of total industry employment in a given occupation from the 
2022 OEWS dataset (BLS, 2023c). The aggregation of these products by 4-
digit NAICS code yields OSHA's estimate of the percentage of all 
employees in a given industry that work in the four climatic work 
conditions.
    OSHA assumes that employees working indoors in environmentally 
controlled workspaces are not covered under the proposed standard 
unless they are exposed to process heat (e.g., kitchens, foundries). It 
is possible that employees exposed to process heat in indoor work 
settings are counted in the O*NET data as being in climatic work 
condition (2) Indoors, Not Environmentally Controlled, and therefore 
already captured in counts of potentially affected employees. However, 
to account for the possibility that some employees exposed to process 
heat are categorized in climatic work condition (1) Indoors, 
Environmentally Controlled (which is possible if survey respondents 
considered areas that were environmentally controlled but hot due to 
process heat to be within the definition of environmentally 
controlled), OSHA relied on the ORS dataset (BLS, 2023d) to identify 
occupations exposed to process heat. To the extent that employees 
exposed to process heat are included in both climatic work condition 
(2) Indoors, Not Environmentally Controlled and the ORS data on 
exposure to extreme heat, this method may overstate the number of 
employees exposed to process heat. The ORS dataset contains estimates 
for the percent of employees that are exposed (or not) to extreme 
heat.\37\ The ORS data are available by SOC occupation code, although 
not all SOC codes have an estimate available for all data series. 
Similar to the estimation for climatic conditions described above, the 
percentage of employees exposed to extreme heat was multiplied by the 
percentage of total industry employment in a given occupation from the 
2022 OEWS dataset (BLS, 2023c), resulting in an estimate of the 
percentage of employees by industry exposed to process heat.
---------------------------------------------------------------------------

    \37\ ORS considers extreme heat present when (1) employees' 
exposure is related to critical tasks and not due to weather and (2) 
the atmosphere is dry with temperatures above 90 [deg]F, or the 
atmosphere is humid with temperatures above 85 [deg]F (BLS, 2021).
---------------------------------------------------------------------------

    OSHA acknowledges that the temperature criteria for the ORS 
definition of exposure to extreme heat has a higher temperature 
criterion than the proposed standard's initial heat trigger of 80 
[deg]F, which, to the extent employees are not otherwise included in 
this analysis because they are in climatic work condition (2) Indoors, 
Not Environmentally Controlled, may result in an undercount of 
employees exposed to process heat.
    The percentage of employees exposed to process heat using this 
method was added to the percentage of employees in exposed climatic 
conditions to determine the total percentage of employees exposed to 
heat for all affected industries.\38\ To estimate the total number of 
potentially affected employees for each industry, OSHA multiplied the 
percentage of total exposed employees in the industry by the OEWS for 
May 2022 (BLS, 2023c) employment totals for that industry.
---------------------------------------------------------------------------

    \38\ To the extent that the employees exposed to process heat 
are already accounted for as being in one of the affected climatic 
conditions (indoors-not environmentally controlled, outdoors- 
exposed to weather, and outdoors- under cover), this method may 
overestimate the percentage of employees and establishments that are 
affected by the proposed standard.
---------------------------------------------------------------------------

    Table VIII.B.3. shows a summary of potentially affected firms, 
establishments, and employees across all these industries by region.

                              Table VIII.B.3--Industry Profile Summarized by Region
----------------------------------------------------------------------------------------------------------------
                         Region                               Entities        Establishments       Employees
----------------------------------------------------------------------------------------------------------------
Alaskan................................................             18,563             21,940            314,444
Central................................................          1,578,125          1,906,757         32,567,699
Eastern................................................          2,157,549          2,631,175         47,954,519
Pacific................................................             33,857             40,139            704,767
Southern...............................................          1,776,945          2,205,794         38,771,537
Western................................................          1,432,624          1,720,933         29,839,496
                                                        --------------------------------------------------------

[[Page 70811]]

 
    Total..............................................          6,997,663          8,526,738        150,152,463
----------------------------------------------------------------------------------------------------------------
Source: OSHA, based on BLS, 2023c; BLS, 2023f; Census Bureau, 2021a; Census Bureau 2023a; Census Bureau, 2023b;
  Census Bureau, 2023d; Census Bureau, 2023a; USDA, 2019; and USFA, 2019.

III. Entities Not Covered by the Proposed Standard
    The proposed standard would apply to all employers in the 
industries outlined in Section VIII.B.II., Potentially Affected 
Industries and Employees, unless they have a workforce that is 
exclusively performing work activities that meet one or more of 
following definitions: (1) work activities for which there is no 
reasonable expectation of exposure at or above the initial heat 
trigger; (2) work activities where the employee is exposed to 
temperatures above the initial heat trigger for fifteen minutes or less 
in any sixty-minute period; (3) emergency response activities of 
workplace emergency response teams or any emergency response activities 
already covered under 29 CFR 1910.120, 1910.146, 1910.156, part 1915, 
subpart P, 1926.65, and 1926.1211; (4) work activities performed in 
indoor work areas or vehicles where air conditioning consistently keeps 
ambient temperature below 80 [deg]F; (5) telework; and (6) sedentary 
work activities in indoor work areas where the work only involves some 
combination of the following: sitting, occasional standing and walking 
for brief periods of time, and occasional lifting of objects weighing 
less than ten pounds. Employees that are exclusively performing these 
types of work activities are also exempt from this standard. Where 
employers and employees are outside OSHA's jurisdiction, they are also 
not covered by the standard and OSHA's estimates of the types and 
number of such employers and employees is discussed in this section.
A. Work Activities With No Reasonable Expectation of Exposure at or 
Above Initial Heat Trigger
    OSHA assumes that the estimates of affected employees cover all 
employees potentially affected by the proposed standard (reported in 
Section VIII.B.II., Potentially Affected Industries and Employees) and 
excludes those employees who are exempt under the scope exemption for 
work activities with no reasonable expectation of exposure at or above 
the initial heat trigger. Employees that are working in ``Indoors, 
Environmentally Controlled'' settings as identified by the O*NET data 
are considered out of scope based on this exemption unless they are 
also exposed to process heat. OSHA believes that this methodology, 
combined with the additional exemptions discussed below, removes from 
scope the employees who would fall under this exemption and thus does 
not make any additional adjustments for this specific exemption.
B. Short Duration Exposure at or Above Initial Heat Trigger
    To estimate the number of employees that might be exposed to 
temperatures at or above the initial heat trigger for fifteen minutes 
or less in any sixty-minute period, OSHA relied on the ORS dataset. For 
indoor work settings, OSHA used the percentages of employees not 
exposed to extreme heat and the percentage of employees seldomly \39\ 
exposed to extreme heat as reflective of those employees that are 
exposed to temperatures at or above the initial heat trigger for 
fifteen minutes or less in any sixty-minute period. For outdoor work 
settings, OSHA used the percentages of employees that either do not 
work outdoors or seldomly work outdoors to estimate the number of 
employees exposed to temperatures at or above the initial heat trigger 
for fifteen minutes or less in any sixty-minute period. OSHA added the 
percentages for each SOC occupation code (OSHA, 2024d).
---------------------------------------------------------------------------

    \39\ ORS defines seldom as spending up to two percent of total 
time working in extreme heat, or less than ten minutes daily, less 
than 45 minutes weekly, or less than one week annually (BLS, 2021).
---------------------------------------------------------------------------

    Using the 2022 OEWS data (BLS, 2023c) described in Section 
VIII.B.II., Potentially Affected Industries and Employees, OSHA 
multiplied the percentage of total industry employment in a given 
occupation and the summation of the percentages of employees in that 
same occupation that are either not exposed or seldomly exposed to 
extreme heat to estimate the percentage of employees in an SOC 
occupation code in a certain industry that meet the exemption criteria 
for indoor employees. These estimates were aggregated for each 4-digit 
NAICS industry to estimate the percentage of total employment in that 
industry that is exposed to temperatures at or above the initial heat 
trigger for fifteen minutes or less in any sixty-minute period. For 4-
digit NAICS industries otherwise captured in OSHA's economic analysis 
that are not available in the OEWS dataset, OSHA used the average 
percentage of employees meeting this definition within the same 
industry sector (2-digit NAICS). This same process also applies for the 
percentages of employees that either do not work outdoors or seldomly 
work outdoors.
    Table VIII.B.4. shows the number of employees that OSHA estimates 
are exempt from the proposed standard because of qualification as 
employees with only short duration exposure.

    Table VIII.B.4--Summary of Employees Exempt Due to Short Duration
                                Exposure
------------------------------------------------------------------------
           Region               Indoor employees      Outdoor employees
------------------------------------------------------------------------
Alaskan.....................               199,838                27,312
Central.....................            21,511,842             2,957,214
Eastern.....................            32,085,256             4,285,342
Pacific.....................               458,099                66,205
Southern....................            25,520,407             3,497,694
Western.....................            19,598,994             2,676,549
                             -------------------------------------------

[[Page 70812]]

 
    Total...................            99,374,435            13,510,315
------------------------------------------------------------------------
Source: OSHA, based on Census Bureau, 2021a; USDA, 2019; Census Bureau,
  2023a; Census Bureau, 2023d; USFA, 2023; BLS, 2023c; and BLS, 2023d.
Note: Due to rounding, figures in the columns and rows may not sum to
  the totals shown.

C. Emergency Response Activities
    OSHA's proposed standard exempts organizations whose primary 
function is the performance of firefighting; emergency response 
activities of workplace emergency response teams, emergency medical 
services, or technical search and rescue; and any emergency response 
activities already covered under 29 CFR 1910.120, 1910.146, 1910.156, 
part 1915, subpart P, 1926.65, and 1926.1211. See the Explanation of 
the Proposed Requirement for Paragraph (a) Scope for a full discussion 
of this exemption.\40\
---------------------------------------------------------------------------

    \40\ OSHA did not attempt to adjust the share of employee's time 
spent engaged in emergency response activities and aside from 
firefighters, did not remove any employees from the scope of the 
standard due to this exemption. To the extent that there are 
additional establishments where employees exclusively perform 
emergency response activities, this analysis may overstate the 
number of affected establishments and employees.
---------------------------------------------------------------------------

    To identify exempt career firefighters, OSHA used the U.S. Fire 
Administration's National Fire Department Registry (USFA, 2023) to 
determine the number of firefighters in each State. Each fire 
department recorded in the National Fire Department Registry is 
considered a firm in the industry profile and each fire station is 
considered an establishment. Employment figures are based on the 
aggregation of counts of active career firefighters. Volunteer and 
paid-per-call firefighters are not included as employees in the data on 
government employees that form the basis of OSHA's estimates of 
government employees, so no adjustment was made to employment regarding 
these responders. (See OSHA-2007-0073-0118, chapter VII, for additional 
information). OSHA welcomes comment on these estimates including 
whether there are additional types of establishments or employees who 
should be considered out of scope for this analysis and suggestions on 
methodologies that could better represent this exemption.
D. Sedentary Work Activities at Indoor Work Areas
    To estimate the number of employees engaged in indoor sedentary 
work activities as defined in the proposed standard, OSHA used ORS and 
OEWS data. The ORS dataset includes estimates for the percent of 
employees involved in work where the strength required is considered 
sedentary.\41\ These data are available by SOC code, although not all 
codes have an estimate available for all data series.
---------------------------------------------------------------------------

    \41\ Sedentary work involves less than or equal to one-third of 
the workday standing while only seldomly or occasionally lifting or 
carrying up to ten pounds.
---------------------------------------------------------------------------

    As described in section VIII.B.III.B., OEWS provides employment 
data for all SOC occupation codes within each 4-digit NAICS industry. 
OSHA multiplied the percentage of total industry employment in a given 
occupation by the percentage of employees in a given SOC code 
considered sedentary (OSHA, 2024d). Similar to the estimates for short 
duration exposure, these percentages were aggregated for each 4-digit 
NAICS industry to estimate the percentage of total employment in that 
NAICS industry that is considered sedentary. For 4-digit NAICS 
industries otherwise captured in OSHA's economic analysis that are not 
available in the OEWS dataset, OSHA used the average percentage of 
employees meeting this definition within the same sector.
    Table VIII.B.5. shows the number of employees that OSHA estimates 
are exempt from the proposed standard because their work is sedentary.

 Table VIII.B.5--Summary of Sedentary Employees Exempt From the Proposed
                                Standard
------------------------------------------------------------------------
                       Region                              Employees
------------------------------------------------------------------------
Alaskan.............................................              66,112
Central.............................................           7,236,687
Eastern.............................................          11,038,630
Pacific.............................................             142,075
Southern............................................           8,543,839
Western.............................................           6,830,356
                                                     -------------------
    Total...........................................          33,857,699
------------------------------------------------------------------------
Source: OSHA, based on Census Bureau, 2021a; USDA, 2019; Census Bureau,
  2023a; Census Bureau, 2023d; USFA, 2023; BLS, 2023c; and BLS, 2023d.
Note: Due to rounding, figures in the columns and rows may not sum to
  the totals shown.

E. Telework
    To estimate the number of employees working remotely, OSHA used the 
2022 BLS Business Response Survey (BRS) data (BLS, 2024a) on telework. 
The BRS provides percentages of employment by sector that are working 
remotely, on-site (i.e., non-remote work), or hybrid. OSHA applied 
these percentages of employment by sector to the employment data 
derived from the sources outlined in Section VIII.B.II., Potentially 
Affected Industries and Employees. Remote employees are considered 
exempt from the proposed standard and hybrid employees are considered 
exempt from the proposed standard during the time they are teleworking.
    Table VIII.B.6. shows the number of employees that OSHA estimates 
work remotely, hybrid, and on-site.

[[Page 70813]]



                        Table VIII.B.6--Summary of On-Site, Remote, and Hybrid Employees
----------------------------------------------------------------------------------------------------------------
                         Region                                Remote             Hybrid            On-site
----------------------------------------------------------------------------------------------------------------
Alaskan................................................              9,933             93,485            206,311
Central................................................          1,100,860         10,324,319         20,885,970
Eastern................................................          1,716,903         15,412,798         30,383,027
Pacific................................................             22,912            195,421            483,328
Southern...............................................          1,391,099         12,060,519         25,087,691
Western................................................          1,100,879          9,289,249         19,318,010
                                                        --------------------------------------------------------
    Total..............................................          5,342,586         47,375,792         96,364,336
----------------------------------------------------------------------------------------------------------------
Source: OSHA, based on BLS 2024a; Census Bureau, 2021a; Census Bureau, 2023a; Census Bureau, 2023d; USDA, 2019;
  and USFA, 2023.
Note: Due to rounding, figures in the columns and rows may not sum to the totals shown.

F. Indoor Work Areas Where Temperature Is Maintained Below 80 [deg]F
    To estimate the number of establishments that might qualify as 
having indoor work areas where the ambient temperature is maintained 
below 80 [deg]F (26.7 [deg]C), OSHA used the Energy Information 
Administration (EIA) Commercial Buildings Energy Consumption Survey 
(CBECS) data (EIA, 2022). The CBECS data provide estimates on the 
number of buildings by building activity with some percentage of cooled 
floorspace. OSHA assumed that buildings with at least 51 percent of 
floorspace cooled qualify as establishments where work activities take 
place in ambient temperatures below 80 [deg]F (26.7 [deg]C). OSHA 
assumed that employees likely work in environmentally controlled areas 
of buildings regardless of what percent of floorspace is cooled. For 
example, loading docks, storage areas, or areas where processes are 
automated may not be cooled but they also may not be regular work 
locations for employees.\42\ OSHA mapped these building activities to 
sectors to estimate the percentage of establishments in a given sector 
that would fit the definition of this exemption. These estimates were 
applied to the number of establishments, as well as the number of 
firms, to determine those firms and establishments that are exempt from 
the proposed standard based on this exemption. OSHA welcomes comment on 
whether this is a reasonable assumption. If not, the agency welcomes 
comment on more appropriate methodologies or data source that might 
better allow OSHA to estimate which establishments would be covered by 
this proposed standard.
---------------------------------------------------------------------------

    \42\ To the extent this assumption is incorrect, this may result 
in too few establishments being considered in-scope of this proposed 
standard which potentially underestimates total establishment-based 
costs. However, this adjustment does not affect the number of 
covered employees who are included or excluded based on their job 
characteristics. The estimated employees who are covered by this 
proposed standard are distributed among the covered establishments. 
If OSHA is counting too few establishments as covered, this would 
mean that the affected employees are concentrated into fewer 
establishments than they truly are and the average cost per 
establishment may be too high.
---------------------------------------------------------------------------

    Table VIII.B.7. shows the number of firms and establishments where 
the ambient temperature indoors is maintained below 80 [deg]F (26.7 
[deg]C).

 Table VIII.B.7--Summary of Entities and Establishments With Sufficient
                         Environmental Controls
------------------------------------------------------------------------
             Region                    Entities         Establishments
------------------------------------------------------------------------
Alaskan.........................              11,047              13,469
Central.........................             883,924           1,142,591
Eastern.........................           1,362,384           1,739,119
Pacific.........................              20,783              25,630
Southern........................           1,096,146           1,428,219
Western.........................             922,625           1,146,582
                                 ---------------------------------------
    Total.......................           4,296,908           5,495,610
------------------------------------------------------------------------
Source: OSHA, based on Census Bureau, 2021a; Census Bureau, 2023a;
  Census Bureau, 2023d; EIA, 2022; USDA, 2019; and USFA, 2023.
Note: Due to rounding, figures in the columns and rows may not sum to
  the totals shown.

G. Employees Working in Cooled Vehicles
    To estimate the number of employees working in cooled vehicles, 
OSHA first estimated the percentage of employees working in vehicles by 
NAICS code. The estimated percentage of drivers is based on the 
percentage of total industry employment in occupations that involve 
driving. OSHA acknowledges that some non-driving occupations may work 
in vehicles and assumes that these occupations are already captured in 
estimates of other work conditions (e.g., they may be included in the 
group working indoors in environmentally controlled settings or working 
outdoors in covered areas). OSHA determined that the following SOC 
occupation codes represent occupations that involve driving vehicles 
exposed to outdoor heat conditions for most of their work activities:
     Postal Service Mail Carriers (43-5052);
     Agricultural Equipment Operators (45-2091);
     Paving, Surfacing, and Tamping Equipment Operators (47-
2071);
     Pile Driver Operators (47-2072);
     Operating Engineers and Other Construction Equipment 
Operators (47-2073);
     Ambulance Drivers and Attendants, Except Emergency Medical 
Technicians (53-3011);
     Driver/Sales Workers (53-3031);
     Heavy and Tractor-Trailer Truck Drivers (53-3032);
     Light Truck Drivers (53-3033);
     Bus Drivers, School (53-3051);
     Bus Drivers, Transit and Intercity (53-3052);
     Shuttle Drivers and Chauffeurs (53-3053);
     Taxi Drivers (53-3054); and

[[Page 70814]]

     Refuse and Recyclable Material Collectors (53-7081).
    OSHA then multiplied the percentage of total industry employment 
comprised of these SOC occupation codes by the percentage of drivers in 
vehicles with sufficiently cooled vehicle cabs. In the absence of data 
on the percentage of vehicles with sufficiently cooled vehicle cabs, 
OSHA estimates that 34 percent of postal service (Hooker and Baker, 
2023) and assumes that 50 percent of all other delivery service drivers 
work in sufficiently cooled vehicle cabs. OSHA welcomes additional data 
on the percent of vehicle cabs that are sufficiently cooled for all 
types of drivers.
    Table VIII.B.8. shows the total number of employees working as 
drivers and those OSHA estimates to be in-scope (i.e., those who are 
not working in sufficiently cooled vehicle cabs).

         Table VIII.B.8--Summary of Drivers, Total and In-Scope
------------------------------------------------------------------------
             Region                     Drivers        In-scope drivers
------------------------------------------------------------------------
Alaskan.........................              10,572               5,419
Central.........................           1,062,955             543,165
Eastern.........................           1,501,620             768,853
Pacific.........................              21,039              10,736
Southern........................           1,249,063             637,255
Western.........................             963,917             490,865
                                 ---------------------------------------
    Total.......................           4,809,165           2,456,292
------------------------------------------------------------------------
Source: OSHA, based on Census Bureau, 2021a; Census Bureau, 2023a; U.S.
  Census Bureau, 2023d; Hooker and Baker, 2023; USDA, 2019; and USFA,
  2023.
Note: Due to rounding, figures in the columns and rows may not sum to
  the totals shown.

H. Exemptions Based on OSHA Jurisdiction
    Beyond the exemptions laid out in the scope section of the proposed 
regulatory text, OSHA must factor in jurisdictional considerations when 
determining those establishments and employees that are in scope of the 
proposed standard. A subset of public entities is considered in-scope 
depending on whether or not the public entity is located in an OSHA 
State Plan State. Those public entities that are in non-State Plan 
States, as well as their employees, are considered out of scope. The 
following States and territories have State Plans: \43\ Alaska, 
Arizona, California, Connecticut, Hawaii, Illinois, Indiana, Iowa, 
Kentucky, Maine, Maryland, Massachusetts, Michigan, Minnesota, Nevada, 
New Jersey, New Mexico, New York, North Carolina, Oregon, Puerto Rico, 
South Carolina, Tennessee, U.S. Virgin Islands, Utah, Vermont, 
Virginia, Washington, and Wyoming.
---------------------------------------------------------------------------

    \43\ Seven of these--Connecticut, Illinois, Maine, 
Massachusetts, New Jersey, New York, and U.S. Virgin Islands--only 
cover public sector employees. The private sector employees in those 
states are covered by Federal OSHA and have been included in this 
analysis.
---------------------------------------------------------------------------

I. Summary of Exempt Employees
    Table VIII.B.9. summarizes the total number of employees estimated 
to be exempt from the proposed standard by each exemption. OSHA 
welcomes comment and feedback on whether the approaches detailed above 
used to estimate the number of employees affected by the proposed 
standard's exemptions are appropriate. The agency welcomes additional 
data or information on how to appropriately account for the exemptions 
in the proposed standard.

                                            Table VIII.B.9--Summary of Employees by Exemption Type by Region
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                           Indoor  short  Outdoor  short
                         Region                              duration         duration       Sedentary        Remote          Hybrid          Drivers
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan.................................................         199,838          27,312          66,112           9,933          93,485           5,153
Central.................................................      21,511,842       2,957,214       7,236,687       1,100,860      10,324,319         519,790
Eastern.................................................      32,085,256       4,285,342      11,038,630       1,716,903      15,412,798         732,767
Pacific.................................................         458,099          66,205         142,075          22,912         195,421          10,302
Southern................................................      25,520,407       3,497,694       8,543,839       1,391,099      12,060,519         611,808
Western.................................................      19,598,994       2,676,549       6,830,356       1,100,879       9,289,249         473,052
                                                         -----------------------------------------------------------------------------------------------
    Total...............................................      99,374,435      13,510,315      33,857,699       5,342,586      47,375,792       2,352,873
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source: OSHA, based on BLS, 2023c; BLS, 2023d; BLS, 2024a; Census Bureau, 2021a; Census Bureau, 2023a; Census Bureau, 20203b; Hooker and Baker, 2023;
  USDA, 2019; and USFA, 2023.
Note: Many employees fit multiple exemption types outlined in this table. The total number of exempt employees is less than the summation of employees
  across all exemption types. Due to rounding, figures in the columns and rows may not sum to the totals shown.

    OSHA welcomes comment and feedback on whether these approaches to 
estimate the number of employees affected by the proposed standard's 
exemptions are appropriate. The agency welcomes additional data or 
information on how to appropriately account for the exemptions in the 
proposed standard.
IV. Affected Employees
    The categories that employees impacted by the proposed exemptions 
fall into are likely to overlap. Employees that perform office work may 
(1) work indoors in climate control, (2) only perform sedentary work 
activities, and (3) may occasionally work remotely. In these 
situations, such employees may be included in the total estimate for 
each of these exemptions discussed above, therefore simply adding the 
totals of

[[Page 70815]]

those exemptions may overstate the number of exempt employees. This 
section adjusts for that overlap and presents the number of estimated 
employees by work condition. This section also presents estimates on 
the number of affected employees by work shift which is used for 
specific cost estimates discussed in Section VIII.C., Costs of 
Compliance.
A. Affected Employees by Work Conditions
    This section estimates the percentage of affected employees by work 
conditions, using the number of employees potentially exposed to heat 
from section VIII.B.II. and the exemptions outlined in section 
VIII.B.III. OSHA recognizes that some employees are likely to fall 
under multiple exemptions. For example, an employee that teleworks and 
performs sedentary work in a climate-controlled environment is included 
in three exemption categories (telework, sedentary, and no reasonable 
expectation of exposure to heat). To avoid double-counting employees, 
OSHA relied on the following method to estimate the number of affected 
employees.
    First, the agency excluded public-sector employees that are not 
within OSHA's jurisdiction, as discussed in section VIII.B.III.H. After 
excluding employees outside OSHA's jurisdiction, the agency applied the 
estimated percentages of employees engaged in sedentary work, as 
estimated in section VIII.B.III.D., to the percentage of employees 
working in indoor, not environmentally controlled work conditions since 
those employees performing sedentary work indoors are exempt regardless 
of the presence of climate control. OSHA assumes that the majority of 
employees estimated to be exempt due to telework, detailed in section 
VIII.B.III.E., are also captured by the sedentary work exemption, and 
therefore did not make an additional adjustment for these employees.
    Next, OSHA applied the estimated percentage of employees exposed to 
extreme heat according to the ORS data (BLS, 2023d) to the percentage 
of employees working in indoor, environmentally controlled work 
conditions to account for employees exposed to process heat who are 
covered by this proposed standard. The percentages of outdoor employees 
(both under cover and exposed to weather) are adjusted to remove from 
scope employees that have short duration outdoor exposure as estimated 
in section VIII.B.III.B. OSHA assumed that indoor employees that are 
exempt based on short duration exposure are likely to be captured in 
the sedentary work exemption and did not make an additional adjustment 
for these employees.
    These percentages were aggregated for each 4-digit NAICS industry 
to estimate the percentage of total employment in that industry that 
work in either indoor, environmentally controlled conditions (while 
only accounting for those employees that are exposed to process heat); 
indoor, not environmentally controlled conditions (while only 
accounting for those employees that are not sedentary); or outdoor 
conditions. For 4-digit NAICS industries otherwise captured in OSHA's 
economic analysis that are not available in the OEWS dataset, OSHA used 
the average percentage of employees meeting these definitions within 
the same sector.
    Table VIII.B.10. shows the number of employees that are considered 
within the scope of the proposed standard, broken out by work 
conditions.

                             Table VIII.B.10--Summary of Employees by Work Condition
----------------------------------------------------------------------------------------------------------------
                                                  Indoor, not
                    Region                      environmentally       Indoor,         Outdoor          Total
                                                   controlled      process  heat
----------------------------------------------------------------------------------------------------------------
Alaskan......................................             38,078           6,240          39,652          83,969
Central......................................          4,119,613         688,813       3,110,084       7,918,510
Eastern......................................          5,677,620       1,011,200       4,545,121      11,233,941
Pacific......................................             80,274          19,346          74,030         173,649
Southern.....................................          4,473,460         822,673       3,448,321       8,744,454
Western......................................          3,780,957         665,729       3,353,115       7,799,801
                                              ------------------------------------------------------------------
    Total....................................         18,170,002       3,214,001      14,570,322      35,954,325
----------------------------------------------------------------------------------------------------------------
Source: OSHA, based on BLS, 2023d; Census Bureau, 2021a; Census Bureau, 2023a; Census Bureau, 2023d; O*NET,
  2023; USDA, 2019; and USFA, 2023.
Note: Due to rounding, figures in the columns and rows may not sum to the totals shown.

B. Affected Employees by Shift Type
    To estimate the number of employees that work during certain 
periods of the day and therefore during different heat conditions, OSHA 
used the American Time Use Survey (ATUS) for 2017-2018 (BLS, 2023a). 
The ATUS outlines the percent of employees that work certain shifts by 
sector. For the purposes of estimating the variations in heat exposure 
over the course of a day, OSHA has categorized these into three shifts: 
daytime, evening, and overnight. OSHA mapped work shifts defined in the 
ATUS to these three categories in the following sections.
I. Daytime
    The daytime work shift category corresponds to the regular daytime 
schedule grouping in the ATUS. The ATUS defines regular daytime 
schedule as having a majority of respondents that worked between 6 a.m. 
and 6 p.m. For this analysis, employees categorized as daytime 
employees are assumed to work between 8 a.m. and 4 p.m. to adjust for 
overlap with the other work shift categories.
II. Evening
    The evening work shift category corresponds to the evening shift in 
the ATUS. The evening schedule is defined as having respondents work a 
majority of the time between 2 p.m. and midnight. For this analysis, 
employees categorized as evening employees are assumed to work between 
4 p.m. and midnight.
III. Overnight
    The overnight work shift category corresponds to the night shift in 
the ATUS. The night schedule is defined as having respondents work a 
majority of the time between 9 p.m. and 8 a.m. For this analysis, 
employees categorized as overnight employees are assumed to work 
between midnight and 8 a.m.

[[Page 70816]]

IV. Other Shift Categories
    There are additional shift groups in the ATUS whose definitions do 
not fit neatly into a certain timeframe (e.g., rotating, irregular, 
split shift, other). The percentages of employees that fit these 
additional groups were evenly distributed across the other categories.
V. Estimates of the Number of In-Scope Employees by Work Shift
    Estimating the number of employees that work certain shifts is 
important because some requirements of the proposed standard are 
dependent on whether the heat index is at or above a trigger while 
employees are working. Employees working in the early afternoon will be 
exposed to warmer temperatures than those working during the evening or 
night hours, and thus will more often qualify for a required rest 
break, as an example.
    Table VIII.B.11. shows the number of employees that OSHA estimates 
work certain work shifts.

                 Table VIII.B.11--Summary of In-Scope Employees by Work Shift and Work Condition
----------------------------------------------------------------------------------------------------------------
                                         Indoor, not
               Region                  environmentally    Indoor,  process       Outdoor             Total
                                          controlled            heat
----------------------------------------------------------------------------------------------------------------
                                                     Daytime
----------------------------------------------------------------------------------------------------------------
Alaskan.............................             32,572              4,683             34,729             71,985
Central.............................          3,520,992            513,412          2,727,273          6,761,677
Eastern.............................          4,858,352            752,843          3,989,031          9,600,226
Pacific.............................             67,919             13,914             64,780            146,614
Southern............................          3,837,670            601,003          3,046,594          7,485,266
Western.............................          3,241,443            492,814          2,952,787          6,687,044
                                     ---------------------------------------------------------------------------
    Subtotal........................         15,558,949          2,378,669         12,815,194         30,752,813
----------------------------------------------------------------------------------------------------------------
                                                     Evening
----------------------------------------------------------------------------------------------------------------
Alaskan.............................              3,151              1,114              2,643              6,908
Central.............................            344,832            126,294            211,761            682,888
Eastern.............................            476,846            186,505            309,284            972,635
Pacific.............................              7,580              4,029              5,298             16,906
Southern............................            376,759            163,150            228,820            768,729
Western.............................            315,621            125,450            221,400            662,471
                                     ---------------------------------------------------------------------------
    Subtotal........................          1,524,789            606,543            979,205          3,110,537
----------------------------------------------------------------------------------------------------------------
                                                    Overnight
----------------------------------------------------------------------------------------------------------------
Alaskan.............................              2,355                442              2,280              5,076
Central.............................            253,789             49,106            171,050            473,945
Eastern.............................            342,421             71,853            246,806            661,079
Pacific.............................              4,774              1,403              3,952             10,129
Southern............................            259,031             58,520            172,907            490,459
Western.............................            223,893             47,465            178,928            450,287
                                     ---------------------------------------------------------------------------
    Subtotal........................          1,086,263            228,789            775,922          2,090,975
----------------------------------------------------------------------------------------------------------------
                                                      Total
----------------------------------------------------------------------------------------------------------------
Alaskan.............................             38,078              6,240             39,652             83,969
Central.............................          4,119,613            688,813          3,110,084          7,918,510
Eastern.............................          5,677,620          1,011,200          4,545,121         11,233,941
Pacific.............................             80,274             19,346             74,030            173,649
Southern............................          4,473,460            822,673          3,448,321          8,744,454
Western.............................          3,780,957            665,729          3,353,115          7,799,801
                                     ---------------------------------------------------------------------------
    Total...........................         18,170,002          3,214,001         14,570,322         35,954,325
----------------------------------------------------------------------------------------------------------------
Source: OSHA, based on BLS, 2023a; BLS, 2023c; BLS 2023d; Census Bureau, 2021a; Census Bureau, 2023a; Census
  Bureau, 203d; O*NET, 2023; USDA, 2019; and USFA, 2023.
Note: Due to rounding, figures in the columns and rows may not sum to the totals shown.

V. Affected Entities
    This section summarizes the total estimated number of entities, 
small entities, and very small entities impacted by the proposed 
standard.
A. Summary of Affected Entities
    Table VIII.B.12. summarizes the number of affected entities by core 
industry and region.

[[Page 70817]]



    Table VIII.B.12--Profile of Affected Entities, Establishments, and Employees, by Core Industry and Region
----------------------------------------------------------------------------------------------------------------
                         Region                               Entities        Establishments       Employees
----------------------------------------------------------------------------------------------------------------
                                       Agriculture, Forestry, and Fishing
----------------------------------------------------------------------------------------------------------------
Alaskan................................................                483                490                892
Central................................................             35,466             35,586            281,481
Eastern................................................             18,684             18,729            160,691
Pacific................................................                253                253              1,666
Southern...............................................             32,393             32,534            237,522
Western................................................             18,176             18,287            453,041
                                                        --------------------------------------------------------
    Subtotal...........................................            105,455            105,879          1,135,293
----------------------------------------------------------------------------------------------------------------
                                   Building Materials and Equipment Suppliers
----------------------------------------------------------------------------------------------------------------
Alaskan................................................                 38                 51              1,142
Central................................................              2,912              4,090            105,785
Eastern................................................              4,280              5,858            131,370
Pacific................................................                 72                 93              2,030
Southern...............................................              3,692              5,338            122,798
Western................................................              2,889              3,876             92,573
                                                        --------------------------------------------------------
    Subtotal...........................................             13,884             19,306            455,698
----------------------------------------------------------------------------------------------------------------
                                               Commercial Kitchens
----------------------------------------------------------------------------------------------------------------
Alaskan................................................                517                623              6,270
Central................................................             36,975             49,684            739,565
Eastern................................................             66,334             83,069          1,100,671
Pacific................................................              1,353              1,605             23,824
Southern...............................................             43,422             60,794            987,885
Western................................................             39,486             52,286            733,222
                                                        --------------------------------------------------------
    Subtotal...........................................            188,087            248,060          3,591,437
----------------------------------------------------------------------------------------------------------------
                                                  Construction
----------------------------------------------------------------------------------------------------------------
Alaskan................................................              2,468              2,518             11,776
Central................................................            161,546            163,268            867,865
Eastern................................................            234,565            236,970          1,264,969
Pacific................................................              3,436              3,477             24,954
Southern...............................................            168,126            171,053          1,232,019
Western................................................            155,060            157,053            947,205
                                                        --------------------------------------------------------
    Subtotal...........................................            725,200            734,340          4,348,789
----------------------------------------------------------------------------------------------------------------
                                      Drycleaning and Commercial Laundries
----------------------------------------------------------------------------------------------------------------
Alaskan................................................                 18                 20                114
Central................................................              1,994              2,485             13,861
Eastern................................................              5,711              6,383             25,423
Pacific................................................                 43                 50                554
Southern...............................................              3,145              3,767             20,037
Western................................................              2,396              2,706             14,349
                                                        --------------------------------------------------------
    Subtotal...........................................             13,307             15,411             74,338
----------------------------------------------------------------------------------------------------------------
                                       Landscaping and Facilities Support
----------------------------------------------------------------------------------------------------------------
Alaskan................................................                111                127              4,334
Central................................................             11,606             13,203            273,784
Eastern................................................             18,686             21,487            443,136
Pacific................................................                238                313              8,574
Southern...............................................             13,103             15,123            367,104
Western................................................              9,836             11,827            262,938
                                                        --------------------------------------------------------
    Subtotal...........................................             53,581             62,080          1,359,870
----------------------------------------------------------------------------------------------------------------
                                             Maintenance and Repair
----------------------------------------------------------------------------------------------------------------
Alaskan................................................                189                217              1,291
Central................................................             20,398             21,964            143,311
Eastern................................................             27,230             29,112            185,126
Pacific................................................                329                350              2,261
Southern...............................................             21,642             23,646            172,454

[[Page 70818]]

 
Western................................................             17,080             18,515            129,094
                                                        --------------------------------------------------------
    Subtotal...........................................             86,868             93,804            633,538
----------------------------------------------------------------------------------------------------------------
                                                  Manufacturing
----------------------------------------------------------------------------------------------------------------
Alaskan................................................                174                207              3,489
Central................................................             31,890             34,082          1,149,535
Eastern................................................             37,652             39,539          1,064,032
Pacific................................................                307                316              3,243
Southern...............................................             27,569             29,654            852,094
Western................................................             26,893             28,053            551,798
                                                        --------------------------------------------------------
    Subtotal...........................................            124,483            131,849          3,624,192
----------------------------------------------------------------------------------------------------------------
                                                   Oil and Gas
----------------------------------------------------------------------------------------------------------------
Alaskan................................................                 72                 98              3,809
Central................................................              3,210              3,976             27,709
Eastern................................................              1,631              2,146             18,110
Pacific................................................                  0                  0                  0
Southern...............................................             11,216             14,406            173,419
Western................................................              1,794              2,110             18,053
                                                        --------------------------------------------------------
    Subtotal...........................................             17,924             22,736            241,099
----------------------------------------------------------------------------------------------------------------
                                          Postal and Delivery Services
----------------------------------------------------------------------------------------------------------------
Alaskan................................................                207                229                273
Central................................................              8,796              9,820             48,711
Eastern................................................             11,053             12,421             77,808
Pacific................................................                112                131                776
Southern...............................................              7,782              9,144             55,205
Western................................................              4,874              5,860             46,414
                                                        --------------------------------------------------------
    Subtotal...........................................             32,824             37,605            229,188
----------------------------------------------------------------------------------------------------------------
                                            Recreation and Amusement
----------------------------------------------------------------------------------------------------------------
Alaskan................................................                261                272              1,156
Central................................................              9,879             10,799            117,890
Eastern................................................             14,551             16,161            196,438
Pacific................................................                185                200              2,558
Southern...............................................              9,316             10,524            153,835
Western................................................              7,815              9,004            138,003
                                                        --------------------------------------------------------
    Subtotal...........................................             42,006             46,961            609,880
----------------------------------------------------------------------------------------------------------------
                                          Sanitation and Waste Removal
----------------------------------------------------------------------------------------------------------------
Alaskan................................................                 19                 22                691
Central................................................                648                815             21,373
Eastern................................................                982              1,176             36,177
Pacific................................................                 15                 18                635
Southern...............................................                642                853             28,844
Western................................................                441                576             22,484
                                                        --------------------------------------------------------
    Subtotal...........................................              2,747              3,460            110,204
----------------------------------------------------------------------------------------------------------------
                                               Telecommunications
----------------------------------------------------------------------------------------------------------------
Alaskan................................................                  7                 30                619
Central................................................                418              1,853             32,035
Eastern................................................                532              2,536             48,653
Pacific................................................                  6                 28                580
Southern...............................................                479              2,227             44,194
Western................................................                384              1,554             28,506
                                                        --------------------------------------------------------
    Subtotal...........................................              1,825              8,228            154,587
----------------------------------------------------------------------------------------------------------------

[[Page 70819]]

 
                                             Temporary Help Services
----------------------------------------------------------------------------------------------------------------
Alaskan................................................                  6                  9                363
Central................................................                910              1,623            340,619
Eastern................................................              1,469              2,286            435,338
Pacific................................................                 14                 22             10,226
Southern...............................................              1,192              1,941            704,748
Western................................................                837              1,395            382,328
                                                        --------------------------------------------------------
    Subtotal...........................................              4,428              7,276          1,873,621
----------------------------------------------------------------------------------------------------------------
                                                 Transportation
----------------------------------------------------------------------------------------------------------------
Alaskan................................................                515                645              4,950
Central................................................             36,839             39,510            214,151
Eastern................................................             32,523             35,567            218,252
Pacific................................................                374                443              7,332
Southern...............................................             31,794             36,180            290,503
Western................................................             23,246             25,732            170,998
                                                        --------------------------------------------------------
    Subtotal...........................................            125,290            138,077            906,187
----------------------------------------------------------------------------------------------------------------
                                                    Utilities
----------------------------------------------------------------------------------------------------------------
Alaskan................................................                 59                 98                817
Central................................................              1,481              4,192             61,651
Eastern................................................              1,628              5,255             86,266
Pacific................................................                 20                 36                336
Southern...............................................              2,678              5,894             73,865
Western................................................              1,470              3,002             41,136
                                                        --------------------------------------------------------
    Subtotal...........................................              7,336             18,477            264,071
----------------------------------------------------------------------------------------------------------------
                                                   Warehousing
----------------------------------------------------------------------------------------------------------------
Alaskan................................................                 21                 22                126
Central................................................              2,247              3,195             74,468
Eastern................................................              2,877              4,040            109,065
Pacific................................................                 42                 51                452
Southern...............................................              2,631              3,966             92,288
Western................................................              2,068              3,000             70,103
                                                        --------------------------------------------------------
    Subtotal...........................................              9,887             14,274            346,503
----------------------------------------------------------------------------------------------------------------
                                                    Non-Core
----------------------------------------------------------------------------------------------------------------
Alaskan................................................              1,907              2,218             41,857
Central................................................            138,849            171,223          3,404,715
Eastern................................................            221,457            269,307          5,632,414
Pacific................................................              3,497              4,224             83,648
Southern...............................................            169,479            211,935          3,135,642
Western................................................            140,429            169,045          3,697,556
                                                        --------------------------------------------------------
    Subtotal...........................................            675,618            827,952         15,995,832
----------------------------------------------------------------------------------------------------------------
                                                      Total
----------------------------------------------------------------------------------------------------------------
Alaskan................................................              7,073              7,895             83,969
Central................................................            506,064            571,365          7,918,510
Eastern................................................            701,843            792,041         11,233,941
Pacific................................................             10,295             11,611            173,649
Southern...............................................            550,301            638,982          8,744,454
Western................................................            455,175            513,879          7,799,801
                                                        --------------------------------------------------------
    Total..............................................          2,230,750          2,535,774         35,954,325
----------------------------------------------------------------------------------------------------------------
Source: OSHA, based on Census Bureau, 2021a; USDA, 2019; Census Bureau, 2023a; Census Bureau, 2023d; and USFA,
  2023.
Note: Due to rounding, figures in the columns and rows may not sum to the totals shown.


[[Page 70820]]

B. Determining Entity Size
    OSHA also estimates the number of firms, establishments, and 
employees that are considered small by both SBA regulations in 13 CFR 
121.201 and the Regulatory Flexibility Act (RFA). Private entities are 
defined as small according to various employment- or revenue-based 
definitions by 6-digit NAICS code as laid out in the SBA table of size 
standards (SBA, 2023). Public entities (or ``small governments'') are 
defined as small if they serve a population of less than 50,000.\44\ 
OSHA also looks at the economic impacts on very small entities, which, 
for all industries, the agency defines as those employing fewer than 20 
employees.
---------------------------------------------------------------------------

    \44\ The RFA also includes small organizations defined as any 
not-for-profit enterprise which is independently owned and operated 
and is not dominant in its field. Traditionally, OSHA considers all 
non-profit organizations to be small entities based on this 
definition. This has the effect of including some very large 
organizations in the analysis of small entities (e.g., some major 
hospital systems with tens of thousands of employees are non-profit 
entities) thus skewing the costs and impacts for the average small 
entity. For this analysis, OSHA did not separately assess impacts on 
non-profit entities. To the extent that non-profit entities are 
similar in size to small for-profit entities (either based on the 
number of employees or revenues), the costs and impact estimates 
would be consistent. The costs of this proposed standard are largely 
employee based and the agency has not found there to be feasibility 
concerns for entities of any size. Including large non-profits in 
the profile of SBA/RFA defined small entities would not alter the 
findings of the Initial Regulatory Flexibility Analysis (See section 
VIII.F.).
---------------------------------------------------------------------------

    For this PEA, OSHA analyzed costs at the 4-digit NAICS code and 
State level. Since there are no SBA definitions of small entities at 
the 4-digit level, OSHA aggregated the number of firms, establishments, 
and employees within each 6-digit NAICS industry to the 4-digit level. 
For employee-based SBA definitions, OSHA summed all economic data 
within employee-class sizes below the SBA-determined cut-off number of 
employees. For revenue-based definitions, OSHA summed all economic data 
for all employee-class sizes under the largest employee-class size 
where the average revenue per firm was under the SBA-determined cut-off 
revenue. Where available, SUSB data is used to estimate firms, 
establishments, and employees by size class. As discussed in section 
VIII.B.II., there are some NAICS industries that are unavailable in the 
SUSB, so OSHA used alternative data sources, as discussed in section 
VIII.B.II.A., to estimate employment and establishment counts by size 
class in those instances.
    For the private sector industries that were missing from the SUSB 
dataset due to data disclosure limitations, OSHA estimated the 
percentage of employment and establishments in each size class category 
using SUSB data where available for the sector and then applied that to 
the total counts of employment and establishments described in Section 
VIII.B.II., Potentially Affected Industries and Employees. OSHA used 
data from the Census of Agriculture (USDA, 2019) to estimate the 
industry characteristics for NAICS industries within the agriculture 
sector and QCEW data for the remaining NAICS industries that were 
missing size class information due to data disclosure limitations.
    Local government data were drawn from the Census Bureau's (2023) 
GUS data for 2022 (BLS, 2023d). The data include the 2021 population of 
each city, county, and town served by the listed local governments. 
Using the GUS data, OSHA found that, of the 38,736 local governments 
listed, 18,028 are in State Plan States and 16,893 of these have a 
population of less than 50,000 and are, thus, considered small. No 
State governments are considered small under the RFA definition.
    Based on the exemption for emergency response activities, OSHA 
estimated the number of fire departments that serve small governmental 
jurisdictions and the number of firefighters that they employ. To 
derive these estimates, OSHA estimated the median population served per 
fire department employee and used that to estimate how many employees a 
department would need to employ to serve a population greater than 
50,000. OSHA used data from two Firehouse Magazine surveys to determine 
the median population served per employee for career and mixed fire 
departments at various employment size classes to extrapolate to the 
entire universe of fire departments. Part 1 of the 2021 National Run 
Survey (Firehouse Magazine, 2022b) presents data from 229 career fire 
departments' statistics about population and staffing. Similarly, the 
2021 Combination Fire Department Run Survey (Firehouse Magazine, 2022a) 
has mixed fire department data. Estimates of the median population 
served per employee derived from both surveys are multiplied by the 
number of employees for each department in the U.S. Fire 
Administration's (USFA, 2022) registry data (used for the Fire 
Department profile (see Section VIII.B.II., Potentially Affected 
Industries and Employees)) within each employee size class to determine 
how many departments serve populations of fewer than 50,000. These 
estimated counts of employees and fire departments corresponding to 
those departments were removed from the count of employees, entities, 
and establishments at affected small governments.
C. Summary of Small and Very Small Entities
    Table VIII.B.13. presents the number of small firms and 
establishments and the number of very small firms and establishments, 
as well as the number of employees estimated to work for these small 
and very small entities. In some industries with revenue-based SBA 
thresholds for small entities, the counts of small affected firms 
(establishments) are less than the counts for very small firms 
(establishments). This occurs when some very small firms 
(establishments) have revenue that exceeds the small entity revenue 
threshold and are therefore not included in the counts of small firms 
(establishments).

             Table VIII.B.13--Profile of Small and Very Small Affected Entities, Establishments, and Employees, by Core Industry and Region
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                        Small (SBA/RFA)                                  Very small (<20)
                        Region                         -------------------------------------------------------------------------------------------------
                                                           Entities      Establishments     Employees       Entities      Establishments     Employees
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                           Agriculture, Forestry, and Fishing
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................             475              478             831             466              466             544
Central...............................................          24,294           24,322         149,091          15,065           15,065          55,208
Eastern...............................................          16,193           16,208         115,421          12,736           12,738          53,826
Pacific...............................................             199              199           1,399             138              138           1,082
Southern..............................................          26,346           26,377         169,979          17,326           17,331          62,951

[[Page 70821]]

 
Western...............................................          16,211           16,268         314,889          10,009           10,012          58,338
                                                       -------------------------------------------------------------------------------------------------
    Subtotal..........................................          83,717           83,853         751,608          55,739           55,750         231,950
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                       Building Materials and Equipment Suppliers
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................              14               15             216              27               27             202
Central...............................................           1,192            1,282          25,975           2,192            2,231          18,113
Eastern...............................................           1,999            2,128          40,838           3,358            3,409          27,914
Pacific...............................................              38               41             679              52               52             395
Southern..............................................           1,814            1,946          34,426           2,855            2,898          23,385
Western...............................................           1,509            1,596          28,722           2,311            2,345          18,858
                                                       -------------------------------------------------------------------------------------------------
    Subtotal..........................................           6,566            7,009         130,856          10,795           10,962          88,866
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                   Commercial Kitchens
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................             509              579           4,603             430              432           1,745
Central...............................................          36,119           40,201         472,283          26,822           26,939         130,727
Eastern...............................................          65,298           69,963         724,441          51,676           51,830         233,251
Pacific...............................................           1,282            1,388          16,812             946              949           4,411
Southern..............................................          42,239           47,058         571,817          31,027           31,159         145,802
Western...............................................          38,954           43,511         487,920          29,838           30,051         149,486
                                                       -------------------------------------------------------------------------------------------------
    Subtotal..........................................         184,402          202,700       2,277,876         140,740          141,361         665,422
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                      Construction
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................           2,383            2,400           6,784           2,277            2,279           4,532
Central...............................................         158,425          158,752         562,118         147,997          148,028         315,449
Eastern...............................................         230,158          230,528         840,221         214,268          214,313         467,181
Pacific...............................................           3,308            3,317          15,761           2,986            2,986           8,179
Southern..............................................         163,896          164,295         695,987         149,782          149,827         359,212
Western...............................................         151,930          152,258         602,318         140,362          140,392         322,939
                                                       -------------------------------------------------------------------------------------------------
    Subtotal..........................................         710,101          711,550       2,723,189         657,671          657,825       1,477,491
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                          Drycleaning and Commercial Laundries
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................              17               19              95              16               17              69
Central...............................................           1,929            2,171           8,814           1,754            1,797           4,391
Eastern...............................................           5,626            5,994          17,624           5,330            5,438          10,761
Pacific...............................................              39               41             313              32               34              83
Southern..............................................           3,087            3,449          12,989           2,843            2,951           7,977
Western...............................................           2,352            2,501           8,319           2,214            2,268           5,138
                                                       -------------------------------------------------------------------------------------------------
    Subtotal..........................................          13,051           14,174          48,155          12,190           12,506          28,419
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                           Landscaping and Facilities Support
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................             105              109           1,938              98               99             860
Central...............................................          11,364           11,974         165,112          10,565           10,796          82,930
Eastern...............................................          18,330           19,096         270,325          17,103           17,308         131,677
Pacific...............................................             223              250           5,027             202              203           2,067
Southern..............................................          12,805           13,271         200,425          11,867           11,974         101,006
Western...............................................           9,634            9,974         152,217           8,953            9,030          77,219
                                                       -------------------------------------------------------------------------------------------------
    Subtotal..........................................          52,461           54,673         795,043          48,789           49,410         395,758
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                 Maintenance and Repair
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................             174              186           1,055             174              176             821
Central...............................................          19,068           19,653         108,461          19,174           19,344          84,101
Eastern...............................................          25,688           26,211         144,821          25,704           25,857         113,180
Pacific...............................................             304              318           1,926             304              306           1,384
Southern..............................................          20,023           20,552         117,782          20,239           20,395          87,092
Western...............................................          15,931           16,477         100,556          16,000           16,166          72,908
                                                       -------------------------------------------------------------------------------------------------
    Subtotal..........................................          81,188           83,397         474,600          81,595           82,245         359,487
--------------------------------------------------------------------------------------------------------------------------------------------------------

[[Page 70822]]

 
                                                                      Manufacturing
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................             161              180           1,703             141              147             430
Central...............................................          28,332           29,454         617,095          20,447           20,529          95,353
Eastern...............................................          33,582           34,481         611,009          25,312           25,388         112,950
Pacific...............................................             282              288           2,422             248              248             818
Southern..............................................          24,499           25,279         450,901          18,822           18,884          83,417
Western...............................................          24,347           24,818         337,592          19,945           19,989          76,876
                                                       -------------------------------------------------------------------------------------------------
    Subtotal..........................................         111,203          114,500       2,020,722          84,915           85,185         369,844
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                       Oil and Gas
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................              53               61             692              29               29              70
Central...............................................           2,861            3,003          15,645           2,423            2,443           4,948
Eastern...............................................           1,391            1,458           9,518           1,116            1,125           2,497
Pacific...............................................               0                0               0               0                0               0
Southern..............................................          10,562           11,375          87,027           8,658            8,691          17,744
Western...............................................           1,561            1,631           9,034           1,306            1,308           2,807
                                                       -------------------------------------------------------------------------------------------------
    Subtotal..........................................          16,428           17,527         121,915          13,532           13,596          28,065
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                              Postal and Delivery Services
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................              21               33              34              18               18              26
Central...............................................           1,374            1,951          11,199           1,168            1,171           1,544
Eastern...............................................           2,238            3,001          18,998           1,899            1,900           2,351
Pacific...............................................              25               36              56              20               20              27
Southern..............................................           1,965            2,731          17,147           1,709            1,720           2,104
Western...............................................           1,533            2,081          17,285           1,302            1,309           1,733
                                                       -------------------------------------------------------------------------------------------------
    Subtotal..........................................           7,155            9,832          64,719           6,115            6,139           7,785
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                Recreation and Amusement
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................             258              262             836             243              244             407
Central...............................................           9,660            9,978          76,652           8,093            8,131          23,284
Eastern...............................................          14,184           14,593         126,221          11,535           11,573          34,163
Pacific...............................................             176              182           1,996             131              131             387
Southern..............................................           9,058            9,335          79,313           7,510            7,547          22,207
Western...............................................           7,620            7,976          68,703           6,226            6,251          18,228
                                                       -------------------------------------------------------------------------------------------------
    Subtotal..........................................          40,956           42,326         353,720          33,738           33,877          98,674
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                              Sanitation and Waste Removal
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................              17               17             260              16               16             144
Central...............................................             598              613          11,803             519              519           5,716
Eastern...............................................             908              925          21,423             763              765           8,892
Pacific...............................................              13               16             510              10               10             186
Southern..............................................             579              600          13,810             481              482           5,650
Western...............................................             403              416          10,566             333              334           4,111
                                                       -------------------------------------------------------------------------------------------------
    Subtotal..........................................           2,517            2,586          58,372           2,120            2,125          24,699
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                   Telecommunications
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................               0                0               0               4                4              18
Central...............................................               6                6              28             281              303           1,237
Eastern...............................................              11               12             108             370              388           1,356
Pacific...............................................               0                0               0               2                3              13
Southern..............................................              14               16             124             341              361           1,341
Western...............................................              14               14              71             271              286           1,089
                                                       -------------------------------------------------------------------------------------------------
    Subtotal..........................................              46               48             332           1,269            1,344           5,054
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                 Temporary Help Services
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................               3                3             111               2                2              24
Central...............................................             746              785          58,271             487              490           4,506

[[Page 70823]]

 
Eastern...............................................           1,258            1,305          92,651             845              847           7,409
Pacific...............................................               9               10           1,444               5                5              43
Southern..............................................           1,001            1,064          81,872             663              666           5,193
Western...............................................             734              765          47,601             520              525           3,995
                                                       -------------------------------------------------------------------------------------------------
    Subtotal..........................................           3,752            3,933         281,950           2,522            2,537          21,170
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                     Transportation
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................             472              551           2,648             402              407             779
Central...............................................          35,362           35,967         100,567          32,172           32,196          40,920
Eastern...............................................          30,938           31,687         109,558          27,247           27,290          38,381
Pacific...............................................             336              378           3,401             248              252             513
Southern..............................................          30,063           31,185         121,185          26,656           26,726          38,318
Western...............................................          22,303           23,056          77,739          19,941           20,008          26,654
                                                       -------------------------------------------------------------------------------------------------
    Subtotal..........................................         119,474          122,823         415,098         106,667          106,879         145,566
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                        Utilities
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................              56               86             742              34               37             110
Central...............................................           1,169            2,078          18,326             711              760           2,076
Eastern...............................................           1,235            2,285          22,667             835              957           2,177
Pacific...............................................              12               25             105               9                9              28
Southern..............................................           2,393            3,494          28,343           1,911            1,960           4,049
Western...............................................           1,279            1,717          11,810           1,067            1,103           3,123
                                                       -------------------------------------------------------------------------------------------------
    Subtotal..........................................           6,144            9,686          81,995           4,568            4,826          11,564
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                       Warehousing
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................              21               22             126              10               10              17
Central...............................................           2,193            3,078          70,279             732              753           1,639
Eastern...............................................           2,820            3,920         105,756           1,034            1,051           2,412
Pacific...............................................              42               51             449               8                8              34
Southern..............................................           2,570            3,800          87,420             965              975           2,066
Western...............................................           2,035            2,888          67,352             806              820           1,817
                                                       -------------------------------------------------------------------------------------------------
    Subtotal..........................................           9,681           13,759         331,382           3,555            3,618           7,985
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                        Non-Core
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................           1,503            1,582          14,497           1,594            1,620           5,729
Central...............................................         109,785          114,774       1,251,037         117,012          117,910         428,271
Eastern...............................................         175,885          181,593       1,867,095         189,755          190,941         648,153
Pacific...............................................           2,738            2,857          22,687           2,818            2,851           9,578
Southern..............................................         133,234          138,262       1,099,714         147,342          148,376         508,465
Western...............................................         113,249          117,242       1,000,087         122,703          123,582         423,075
                                                       -------------------------------------------------------------------------------------------------
    Subtotal..........................................         536,394          556,310       5,255,118         581,225          585,280       2,023,270
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                          Total
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................           6,241            6,582          37,172           5,982            6,031          16,526
Central...............................................         444,478          460,042       3,722,756         407,614          409,405       1,300,411
Eastern...............................................         627,742          645,388       5,138,694         590,884          593,119       1,898,531
Pacific...............................................           9,027            9,397          74,988           8,161            8,205          29,227
Southern..............................................         486,148          504,089       3,870,261         450,999          452,925       1,477,979
Western...............................................         411,599          425,189       3,342,781         384,105          385,778       1,268,393
                                                       -------------------------------------------------------------------------------------------------
    Total.............................................       1,985,235        2,050,685      16,186,651       1,847,745        1,855,463       5,991,068
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source: OSHA, based on BLS, 2023; Census Bureau, 2021a; Census Bureau, 2023a; Census Bureau, 2023b; Census Bureau, 2023d; Firehouse Magazine, 2022a;
  Firehouse Magazine 2022b; SBA 2023; USDA, 2019; USFA, 2023.
Note: Due to rounding, figures in the columns and rows may not sum to the totals shown.


[[Page 70824]]

C. Costs of Compliance

I. Introduction
    This section presents OSHA's preliminary analysis of the compliance 
costs associated with the proposed standard for Heat Injury and Illness 
Prevention in Outdoor and Indoor Work Settings.
    OSHA estimates that the proposed standard would cost annually $7.8 
billion (in 2023 dollars) at a discount rate of 2 percent. On average, 
the annualized cost per establishment is estimated to be $3,085.\45\ 
All costs were annualized using a discount rate of 2 percent, 
consistent with OMB Circular A-4 (OMB, 2023).\46\ A 10-year period is 
used to annualize one-time costs or other costs that do not occur every 
year. Note that the benefits of the proposed standard, discussed in 
Section VIII.E., Benefits, are also annualized over a 10-year period. 
Therefore, the time horizon of OSHA's complete analysis of this 
proposed standard is 10 years. Employment and production in affected 
sectors are implicitly held constant over this time horizon for 
purposes of the analysis.
---------------------------------------------------------------------------

    \45\ Spreadsheet detailing all calculations discussed in this 
analysis are available in Analytical Support for OSHA's Preliminary 
Economic Analysis for the Heat Injury and Illness Prevention (OSHA, 
2024c).
    \46\ Section VIII.C.V., Total Costs, presents total annualized 
costs, discounted (2 percent over a 10-year period) and 
undiscounted.
---------------------------------------------------------------------------

    While some employers may be able to make fixed investments to 
reduce their marginal per-employee costs (e.g., on-site freezers, air 
conditioning) as a result of the proposed standard, for the purposes of 
this cost analysis OSHA assumes that employers do not make these 
adjustments. This assumption may result in an overestimate of the costs 
of compliance (e.g., for some firms it may be less costly to install 
air conditioning rather than increasing rest break time for employees). 
The agency also did not explore all potential societal costs (i.e., 
those that do not affect the proposed standard's economic feasibility). 
OSHA welcomes comment on other impacts the rule may have on employees 
that the agency has not considered in this preliminary analysis but 
should consider in the final analysis.
    The remainder of this section is organized as follows: first, OSHA 
discusses cost assumptions used in the analysis, followed by the 
derivation of the wage rates used to estimate labor costs. Next, OSHA 
presents unit and total costs by affected industry sector and region 
and by applicable provision of the proposed standard. The final section 
presents the total costs of the proposed standard for all affected 
entities and employees as well as those that meet the SBA/RFA 
definitions of small entities and those with fewer than 20 employees. 
Discussion of burden reducing regulatory alternatives and regulatory 
options that may increase costs of compliance are discussed in Section 
VIII.F.II.G., Alternatives and Regulatory Options to the Proposed Rule.
II. Cost Assumptions
    This section describes the cost assumptions used in this analysis 
including those relevant to baseline conditions, temperature, and heat-
related incidence rates. OSHA welcomes comment on all assumptions and 
estimates discussed in this section. Additional data or suggestions on 
methodological changes the agency should consider are also welcome.
A. Baseline Non-Compliance Rates
    The estimated costs of the proposed standard are measured against 
the baseline activities of the affected industries, including core and 
non-core industries (see Section VIII.B., Profile of Affected 
Industries for a discussion and definition of core industries). The 
baseline for this analysis includes existing conformity 
(``compliance'') with the provisions of the proposed standard. 
Compliance costs are estimated only for ``non-compliant'' entities with 
practices that currently do not conform to the proposed standard and 
who would therefore incur costs to comply with it.
    OSHA developed baseline non-compliance rates (percent of non-
compliant entities) based on a review of existing State requirements 
(e.g., State heat standards, non-heat-specific paid rest break State 
laws \47\), State-level workforce characteristics (e.g., prevalence of 
piece-rate pay, collective bargaining), and other industry practices 
when employees are exposed to heat-related hazards in the workplace, 
datasets and reports detailing current practices within specific 
industries, feedback from participants in the Small Business Advocacy 
Review (SBAR) Panel, and professional expertise of OSHA staff. OSHA 
prioritized the use of State-specific data sources wherever possible; 
however, in the absence of State-specific data, national data sources 
were used to develop baseline non-compliance rates. In some instances, 
no data were available to develop baseline non-compliance rates for 
certain provisions within certain industries. In these cases, OSHA 
assumed default non-compliance rates for those industries, in some 
cases distinguishing between core and non-core industries (see section 
VIII.B.II.A. for more information on core industries). For certain 
provisions (i.e., heat hazard evaluation and acclimatization), OSHA 
believes that non-compliance rates among core industries may be lower 
than those within non-core industries (i.e., employers in core 
industries are doing more of what OSHA would require under this 
proposed standard) because core industries have more affected 
employees, and more heat-related hazards present in their work 
processes. For this reason, core industries may be more likely to have 
policies and procedures in place to protect employees from heat-related 
hazards on their work sites than employers in non-core industries who 
may be less aware of heat hazards present in their workplace. However, 
for other provisions (e.g., providing drinking water and rest break 
policies) current employment practices are affected by factors beyond 
heat; therefore, OSHA assumes default non-compliance rates for all 
industries, assuming they are the same for core and non-core 
industries.
---------------------------------------------------------------------------

    \47\ In most cases, Federal law does not require the provision 
of rest breaks, see https://www.dol.gov/general/topic/workhours/breaks.
---------------------------------------------------------------------------

    Some States already have heat standards that address some or all 
settings in the State. While the agency estimates that all covered 
employers would incur some costs to comply with this proposed standard, 
employers in States that have heat standards will likely have lower 
compliance costs since they are already doing some of what would be 
required by OSHA. This is reflected in this analysis. Table VIII.C.1. 
shows the States with existing State heat standards and the 
corresponding industries and work settings within the scope of those 
State standards.

[[Page 70825]]



Table VIII.C.1--States and Industries With Existing State Heat Standards
------------------------------------------------------------------------
            Sector                    State                Source
------------------------------------------------------------------------
Outdoor Settings--NAICS 11,     California.......  Cal. Code of Regs.
 23, 2111, 213111, 213112,                          tit. 8, section 3395
 561730 \a\.                                        (2005).
Indoor and Outdoor Settings--   Colorado.........  7 Colo. Code Regs.
 NAICS11.                                           section 1103-15
                                                    (2022).
Indoor Settings--All Sectors..  Minnesota........  Minn. R. 5205.0110
                                                    (1997).
Indoor and Outdoor Settings--   Oregon...........  Or. Admin. R. 437-002-
 All sectors.                                       0156 (2022); Or.
                                                    Admin. R. 437-004-
                                                    1131 (2022).
Outdoor Settings--All Sectors.  Washington.......  Wash. Admin. Code
                                                    sections 296-62-095
                                                    through 296-62-
                                                    09560; 296-307-097
                                                    through 296-307-
                                                    09760 (2023).
------------------------------------------------------------------------
\a\ California's standard only covers outdoor workers within select
  industries within sector 11. Covered agricultural sectors include
  1111, 1112, 1113, 1114, 1119, 1121, 1122, 1123, 1124, 1125, 1129,
  1151, and 1152.

    Since all affected establishments would need to incur some cost to 
develop a HIIPP that meets OSHA's requirements, OSHA assumes that even 
establishments with existing HIIPPs in place would incur costs to 
review and modify their HIIPP to meet OSHA's requirements. Table 
VIII.C.2. shows the percentages of establishments estimated to have 
existing HIIPPs in place in certain industries and States.

       Table VIII.C.2--Percentage of Establishments With Existing Heat Injury and Illness Prevention Plans
----------------------------------------------------------------------------------------------------------------
                                                                     Percent of
                Sector                            State            establishments              Source
----------------------------------------------------------------------------------------------------------------
NAICS 11, 23, 2111, 213111, 213112,     California...............       \b\ 100.0  Cal. Code of Regs. tit. 8,
 4841, 4842, 4884, 4889, 561730 \a\.                                                section 3395 (2005).
Sector 11.............................  Colorado.................           100.0  7 Colo. Code Regs. section
                                                                                    1103-15 (2022).
All Sectors...........................  Minnesota................           100.0  Minn. R. 5205.0110 (1997).
All Sectors...........................  Oregon...................           100.0  Or. Admin. R. 437-002-0156
                                                                                    (2022); Or. Admin. R. 437-
                                                                                    004-1131 (2022).
All Sectors...........................  Washington...............           100.0  Wash. Admin. Code sections
                                                                                    296-62-095 through 296-62-
                                                                                    09560; 296-307-097 through
                                                                                    296-307-09760 (2023).
Sectors 23 and 31-33..................  National.................            75.0  OSHA Estimate.
Core Industries.......................  National.................            50.0  OSHA Estimate.
Non-Core Industries...................  National.................            10.0  OSHA Estimate.
----------------------------------------------------------------------------------------------------------------
\a\ California's standard only covers select industries within sector 11. Covered agricultural sectors include
  1111, 1112, 1113, 1114, 1119, 1121, 1122, 1123, 1124, 1125, 1129, 1151, and 1152.
\b\ California's standard specifies that 6-digit NAICS industries 213111, 213112, and 561730 need to follow the
  requirements of that rule. Since OSHA analyzes costs and economic impacts for this proposed standard at the 4-
  digit NAICS level, OSHA assumes that only a subset of NAICS 2131 and 5617 in California are already compliant
  with the requirements of OSHA's proposed standard. For NAICS 2131, OSHA assumes that 40 percent of NAICS 2131
  are already compliant (since 213111 and 213112 represent two of the five 6-digit NAICS within the 4-digit
  NAICS 2131). For NAICS 5617, OSHA assumes that 20 percent of NAICS 5617 are already compliant (since 561730
  represents one of the five 6-digit NAICS within the 4-digit NAICS 5617).

    Table VIII.C.3. shows the estimated baseline non-compliance rates 
for rest breaks at both the initial and high heat triggers by State. 
OSHA estimated State-level non-compliance rates for rest breaks at the 
initial and high heat triggers based on a review of existing State 
requirements (State heat standards, non-heat-specific paid rest break 
State laws), State-level workforce characteristics (prevalence of 
piece-rate pay, collective bargaining), and existing paid rest breaks 
in collective bargaining agreements (Justia, 2022; DOL, 2023a; DOL, 
2023b; NCFH, 2022; Gittleman and Pierce, 2013; Adams et al. 2009; 
Hirsch et al., n.d.; DOL, 2024b).
    For each State, the State-level non-compliance rate for initial 
heat trigger rest breaks is assumed to be equal to the percentage of 
non-union piece-rate workers in that State.\48\ Based on review of 
existing collective bargaining agreements, feedback from Small Entity 
Representatives during the SBAR Panel process reporting high current 
compliance with if-needed rest breaks (which is also consistent with 
worker surveys such as Mirabelli et al. (2010) and Langer et al. (2021) 
reporting high current compliance with if-needed rest breaks), and 
evidence that piece-rate workers are incentivized to work faster and 
take fewer rest breaks than non-piece-rate workers as reported in focus 
group discussions with U.S. farmworkers (Wadsworth et al., 2019; Lam et 
al., 2013), OSHA assumes that, nationwide, all non-piece-rate workers 
and workers affiliated with a union (both piece-rate and non-piece-
rate) are already allowed rest breaks if needed from their employer.
---------------------------------------------------------------------------

    \48\ Detailed formulas are available in Noncompliance Rates for 
Rest Breaks (OSHA, 2024e).
---------------------------------------------------------------------------

    State-level non-compliance rates for high heat trigger rest breaks 
were calculated based on the State or territory's current paid rest 
break laws, State heat standards, prevalence of rest breaks in 
collective bargaining agreements, and the share of employees affiliated 
with a union (by membership or representation).\49\ The rationale

[[Page 70826]]

behind the formulas is as follows. Non-union piece-rate employees in 
any State are likely the least protected, currently assumed to be 
taking zero breaks at the high heat trigger.\50\ Non-union non-piece-
rate employees are likely most protected in States with a heat standard 
(i.e., these employees are getting most required scheduled rest breaks 
in addition to if-needed rest breaks), less protected in States with 
some non-heat-related paid break law (these workers are getting some 
scheduled rest breaks), and the least protected in States with no paid 
break law (these employees may be getting no scheduled rest breaks). 
Also, in any State, OSHA assumes that employees (both piece-rate and 
non-piece-rate) affiliated with a union are more protected than non-
union employees by being provided some scheduled as well as if-needed 
rest breaks. Collective bargaining agreements differ across employers 
and States; however, collective bargaining agreements are likely more 
protective (meaning employees covered by a union are likely to get more 
scheduled rest breaks) in States with a heat standard or non-heat-
related paid break law than in States with no paid break law.
---------------------------------------------------------------------------

    \49\ Detailed formulas are available in Noncompliance Rates for 
Rest Breaks (OSHA, 2024e). In estimating unit costs of compliance 
with the high heat trigger breaks, OSHA estimates that employers 
that are fully noncompliant in outdoor and indoor settings will 
incur 47 minutes and 41 minutes per employee, respectively. However, 
in the State-level baseline compliance calculations OSHA assumes 
that employers (indoor and outdoor) that offer 47 minutes of break 
plus travel time are 100 percent compliant with the high heat 
trigger breaks. This simplifying assumption results in an 
underestimate of baseline compliance for indoor employers--employers 
with indoor workers that are technically currently 100 percent 
compliant by already providing 41 minutes of break time (including 
travel time) are calculated as being 87 percent compliant (41 
minutes provided/47 minutes), instead of 100 percent (fully 
compliant).
    \50\ This assumption may overestimate non-compliance of 
employers of piece-rate workers in states that have laws requiring 
paid rest breaks for piece-rate workers (in all sectors for 
California, in the agricultural sector for Washington State).
---------------------------------------------------------------------------

    OSHA acknowledges that there is limited information on current 
baseline non-compliance rates for rest breaks in (1) States without 
existing rest breaks laws and (2) States with existing rest break laws. 
OSHA welcomes feedback on the assumptions and estimates of rest break 
non-compliance by State (and territory) described above. OSHA is 
soliciting feedback on whether the assumptions regarding compliance 
differences by workforce characteristics (e.g., piece rate workers, 
union work, State break laws, State heat laws) are reasonable or if 
there are alternative methods, sources of data, or assumptions that 
should be considered. OSHA is especially interested in existing 
research or data sources that can be used to evaluate the impact of 
rest breaks in States with existing requirements.

 Table VIII.C.3--Rest Break Non-Compliance Rates by State and Territory
------------------------------------------------------------------------
                              Initial heat trigger    High heat trigger
            State                      (%)                   (%)
------------------------------------------------------------------------
Alabama.....................                   6.3                  67.7
Alaska......................                   6.0              \a\ 65.7
American Samoa \b\..........                   6.2                  67.1
Arkansas....................                   6.4                  68.3
Arizona.....................                   6.6                  70.0
California..................                   5.7                  13.7
Colorado....................                   6.3                  15.3
Connecticut.................                   6.0                  65.9
District of Columbia........                   6.3                  67.9
Delaware....................                   6.3                  67.9
Florida.....................                   6.6                  69.7
Georgia.....................                   6.6                  69.5
Guam \b\....................                   6.2                  67.1
Hawaii......................                   4.8                  58.4
Idaho.......................                   6.6                  69.5
Illinois....................                   5.8                  28.4
Indiana.....................                   6.1                  66.3
Iowa........................                   6.3                  67.6
Kansas......................                   6.0                  66.2
Kentucky....................                   6.0                  29.0
Louisiana...................                   6.6                  69.6
Maine.......................                   6.4                  68.2
Maryland....................                   6.2                  29.8
Massachusetts...............                   5.9                  65.6
Michigan....................                   5.6                  63.2
Minnesota...................                   5.9                  28.6
Mississippi.................                   6.0                  66.2
Missouri....................                   5.9                  65.5
Montana.....................                   6.0                  66.0
Nebraska....................                   6.4                  68.4
Nevada......................                   5.6                  27.4
New Hampshire...............                   6.4                  68.4
New Jersey..................                   5.5                  62.9
New Mexico..................                   6.4                  68.7
New York....................                   5.2                  61.1
North Carolina..............                   6.7                  70.4
North Dakota................                   6.4                  68.3
Northern Mariana Islands \b\                   6.2                  67.1
Ohio........................                   6.0                  65.6
Oklahoma....................                   6.6                  69.6
Oregon......................                   5.9                   5.9
Pennsylvania................                   5.8                  64.9
Puerto Rico \b\.............                   6.2                  67.1
Rhode Island................                   5.9                  65.0
South Carolina..............                   6.7                  70.6
South Dakota................                   6.7                  70.5

[[Page 70827]]

 
Tennessee...................                   6.4                  68.6
Texas.......................                   6.6                  69.7
Utah........................                   6.5                  68.8
U.S. Virgin Islands \b\.....                   6.2                  67.1
Vermont.....................                   5.8                  64.9
Virginia....................                   6.6                  69.9
Washington..................                   5.5                  13.3
West Virginia...............                   6.0                  66.0
Wisconsin...................                   6.2                  67.1
Wyoming.....................                   6.6                  69.5
------------------------------------------------------------------------
\a\ The weather data (discussed in Section VIII.B., Profile of Affected
  Industries) do not show Alaska meeting or exceeding the high heat
  trigger. However, OSHA applied the same assumptions used for other
  States to arrive at a non-compliance rate for Alaska that would be
  applied if there were exposure to heat at or above the high heat
  trigger. In the current analysis, the cost for high heat trigger rest
  breaks is zero for employers in Alaska. In the event that the
  estimation methodology for exposure to heat used in the final analysis
  is changed in a manner that results in employees in Alaska being found
  to be exposed to heat at or above the high heat trigger, this non-
  compliance rate will be applied in those situations.
\b\ Rest break non-compliance rates for U.S. territories were imputed
  using the employment-weighted average of the non-compliance rates of
  the States without any paid break law.
Source: OSHA estimates based on Justia, 2022; DOL, 2023a; DOL, 2023b;
  NCFH, 2022; Gittleman and Pierce, 2013; Adams et al. 2009; Hirsch et
  al., n.d.; DOL, 2024b; formulas in OSHA, 2024e.

    Table VIII.C.4. shows the estimated baseline non-compliance rates 
for all other requirements of the proposed standard. Within certain 
provisions, OSHA outlines different non-compliance rates for certain 
requirements under each provision (e.g., OSHA found that some State 
rules require initial training on heat-related hazards for employees 
but do not require refresher training).
    OSHA welcomes feedback on the baseline non-compliance estimates 
that are detailed in table VIII.C.4. OSHA seeks information and 
feedback on the following topics: alternative sources; existing 
employer practices in States with or without existing heat regulations; 
variation in non-compliance based on employer size, industry, and 
occupation; and the assumption that non-core industries tend to have 
lower baseline compliance (and higher non-compliance) than core 
industries.

                                Table VIII.C.4--Non-Compliance Rates by Provision
----------------------------------------------------------------------------------------------------------------
                                                                   Non-compliance
            Industry/sector                       State             estimate (%)               Source
----------------------------------------------------------------------------------------------------------------
                                     Heat Injury and Illness Prevention Plan
----------------------------------------------------------------------------------------------------------------
Develop or Modify HIIPP:
    All Sectors \a\...................  National................            100.0  OSHA estimate.
Review HIIPP:
    All Sectors.......................  National................             50.0  OSHA estimate.
Employee Involvement:
    All Sectors.......................  National................             75.0  OSHA estimate.
----------------------------------------------------------------------------------------------------------------
                                            Identifying Heat Hazards
----------------------------------------------------------------------------------------------------------------
Environmental Monitoring--Outdoor:
    NAICS 11, 23, 2111, 213111,         California..............          \c\ 0.0  Cal. Code of Regs. tit. 8,
     213112, 4841, 4842, 4884, 4889,                                                section 3395 (2005).
     561730 \b\.
    Sector 11.........................  Colorado................              0.0  7 Colo. Code Regs. section
                                                                                    1103-15 (2022).
    All Sectors.......................  Minnesota...............              0.0  Minn. R. 5205.0110 (1997).
    All Sectors.......................  Oregon..................              0.0  Or. Admin. R. 437-002-0156
                                                                                    (2022); Or. Admin. R. 437-
                                                                                    004-1131 (2022).
    All Sectors.......................  Washington..............              0.0  Wash. Admin. Code sections
                                                                                    296-62-095 through 296-62-
                                                                                    09560; 296-307-097 through
                                                                                    296-307-09760 (2023).
    Sectors 23 and 31-33..............  National................             16.7  OSHA, 2023.
    All Other Industries..............  National................             20.0  OSHA Estimate.
Environmental Monitoring--Indoor:
    NAICS 11, 23, 2111, 213111,         California..............          \c\ 0.0  Cal. Code of Regs. tit. 8,
     213112, 4841, 4842, 4884, 4889,                                                section 3395 (2005).
     561730 \b\.
    Sector 11.........................  Colorado................              0.0  7 Colo. Code Regs. section
                                                                                    1103-15 (2022).
    All Sectors.......................  Minnesota...............              0.0  Minn. R. 5205.0110 (1997).
    All Sectors.......................  Oregon..................              0.0  Or. Admin. R. 437-002-0156
                                                                                    (2022); Or. Admin. R. 437-
                                                                                    004-1131 (2022).
    All Sectors.......................  Washington..............              0.0  Wash. Admin. Code sections
                                                                                    296-62-095 through 296-62-
                                                                                    09560; 296-307-097 through
                                                                                    296-307-09760 (2023).

[[Page 70828]]

 
    Sectors 23 and 31-33..............  National................             16.7  OSHA, 2023.
    All Other Core Industries.........  National................             50.0  OSHA Estimate.
    All Other Non-Core Industries.....  National................             90.0  OSHA Estimate.
Hazard Evaluation:
    NAICS 2211........................  National................             28.3  Kaltsatou et al., 2021.
    Sectors 23 and 31-33..............  National................              7.7  OSHA, 2023.
    All Other Core Industries.........  National................             50.0  OSHA Estimate.
    All Other Non-Core Industries.....  National................             90.0  OSHA Estimate.
Employee Involvement:
All sectors...........................  National................             75.0  OSHA Estimate.
----------------------------------------------------------------------------------------------------------------
                                Requirements at or Above the Initial Heat Trigger
----------------------------------------------------------------------------------------------------------------
Drinking Water:
    NAICS 11, 23, 2111, 213111,         California..............          \c\ 0.0  Cal. Code of Regs. tit. 8,
     213112, 4841, 4842, 4884, 4889,                                                section 3395 (2005).
     561730 \b\.
    Sector 23.........................  Texas...................             59.0  Workers Defense Project,
                                                                                    2013.
    Sector 11 \d\.....................  National................              3.0  DOL, 2022.
    All Other Industries..............  National................             10.0  OSHA Estimate.
Break Area(s) at Outdoor Work Sites:
    NAICS 11, 23, 2111, 213111,         California..............          \c\ 0.0  Cal. Code of Regs. tit. 8,
     213112, 4841, 4842, 4884, 4889,                                                section 3395 (2005).
     561730 \b\.
    Sectors 23 and 31-33..............  National................             20.0  OSHA, 2023.
    All Other Core Industries.........  National................             50.0  OSHA Estimate.
    All Other Non-Core Industries.....  National................             90.0  OSHA Estimate.
Indoor Work Area and Break Area
 Controls:
    All Sectors.......................  Oregon..................              0.0  Or. Admin. R. 437-002-0156
                                                                                    (2022); Or. Admin. R. 437-
                                                                                    004-1131 (2022).
    Sectors 23 and 31-33..............  National................             50.0  OSHA, 2023.
    All Other Core Industries.........  National................             50.0  OSHA Estimate.
    All Other Non-Core Industries.....  National................             90.0  OSHA Estimate.
Acclimatization--New Employees:
    NAICS 11, 23, 2111, 213111,         California..............            \c\ 0  Cal. Code of Regs. tit. 8,
     213112, 4841, 4842, 4884, 4889,                                                section 3395 (2005).
     561730 \b\.
    Sectors 23 and 31-33..............  National................             44.8  OSHA, 2023.
    NAICS 2111........................  National................             72.0  Ergodyne, 2020.
    All Other Core Industries.........  National................             50.0  OSHA Estimate.
    All Other Non-Core Industries.....  National................             90.0  OSHA Estimate.
Acclimatization--Returning Employees:
    Sector 11.........................  Colorado................              0.0  7 Colo. Code Regs. section
                                                                                    1103-15 (2022).
    All Sectors.......................  Oregon..................              0.0  Or. Admin. R. 437-002-0156
                                                                                    (2022); Or. Admin. R. 437-
                                                                                    004-1131 (2022).
    Sectors 23 and 31-33..............  National................             67.2  OSHA, 2023.
    All Other Core Industries.........  National................             50.0  OSHA Estimate.
    All Other Non-Core Industries.....  National................             90.0  OSHA Estimate.
Effective Communication--Supervisor
 \e\:
    All sectors.......................  National................             25.0  OSHA Estimate.
Effective Communication--Employee \e\:
All sectors...........................  National................             50.0  OSHA Estimate.
----------------------------------------------------------------------------------------------------------------
                                 Requirements at or Above the High Heat Trigger
----------------------------------------------------------------------------------------------------------------
Observation for Signs and Symptoms--
 Supervisor:
    All Sectors.......................  National................             25.0  OSHA Estimate.
Observation for Signs and Symptoms--
 Employee:
    All Sectors.......................  National................             50.0  OSHA Estimate.
Hazard Alert:
    NAICS 11, 23, 2111, 213111,         California..............          \c\ 0.0  Cal. Code of Regs. tit. 8,
     213112, 4841, 4842, 4884, 4889,                                                section 3395 (2005).
     561730 \b\.
    Sector 11.........................  Colorado................              0.0  7 Colo. Code Regs. section
                                                                                    1103-15 (2022).
    Sectors 23 and 31-33..............  National................              9.1  OSHA, 2023.
    All Other Core Industries.........  National................             50.0  OSHA Estimate.
    All Other Non-Core Industries.....  National................             90.0  OSHA Estimate.
----------------------------------------------------------------------------------------------------------------
                                Heat Illness and Emergency Response and Planning
----------------------------------------------------------------------------------------------------------------
NAICS 11, 23, 2111, 213111, 213112,     California..............          \c\ 0.0  Cal. Code of Regs. tit. 8,
 4841, 4842, 4884, 4889, 561730 \b\                                                 section 3395 (2005).
Sector 11.............................  Colorado................             50.0  7 Colo. Code Regs. section
                                                                                    1103-15 (2022).
Sectors 23 and 31-33..................  National................             16.7  OSHA, 2023.
All Other Core Industries.............  National................             50.0  OSHA Estimate.

[[Page 70829]]

 
All Other Non-Core Industries.........  National................             90.0  OSHA Estimate.
----------------------------------------------------------------------------------------------------------------
                                                    Training
----------------------------------------------------------------------------------------------------------------
Initial Training:
    NAICS 11, 23, 2111, 213111,         California..............          \c\ 0.0  Cal. Code of Regs. tit. 8,
     213112, 4841, 4842, 4884, 4889,                                                section 3395 (2005).
     561730 \b\.
    Sector 11.........................  Colorado................              0.0  7 Colo. Code Regs. section
                                                                                    1103-15 (2022).
    All Sectors.......................  Minnesota...............              0.0  Minn. R. 5205.0110 (1997).
    All Sectors.......................  Oregon..................              0.0  Or. Admin. R. 437-002-0156
                                                                                    (2022); Or. Admin. R. 437-
                                                                                    004-1131 (2022).
    All Sectors.......................  Washington..............              0.0  Wash. Admin. Code sections
                                                                                    296-62-095 through 296-62-
                                                                                    09560; 296-307-097 through
                                                                                    296-307-09760 (2023).
    Sectors 23 and 31-33..............  National................             20.0  OSHA, 2023.
    NAICS 2211........................  National................             26.1  Kaltsatou et al., 2021.
    All Other Core Industries.........  National................             50.0  OSHA Estimate.
    All Other Non-Core Industries.....  National................             90.0  OSHA Estimate.
----------------------------------------------------------------------------------------------------------------
                                               Refresher Training
----------------------------------------------------------------------------------------------------------------
Sector 11.............................  Colorado................              0.0  7 Colo. Code Regs. section
                                                                                    1103-15 (2022).
    All Sectors.......................  Minnesota...............              0.0  Minn. R. 5205.0110 (1997).
    All Sectors.......................  Oregon..................              0.0  Or. Admin. R. 437-002-0156
                                                                                    (2022); Or. Admin. R. 437-
                                                                                    004-1131 (2022).
    All Sectors.......................  Washington..............              0.0  Wash. Admin. Code sections
                                                                                    296-62-095 through 296-62-
                                                                                    09560; 296-307-097 through
                                                                                    296-307-09760 (2023).
    Sectors 23 and 31-33..............  National................              0.0  OSHA, 2023.
    All Other Core Industries.........  National................             50.0  OSHA Estimate.
All Other Non-Core Industries.........  National................             90.0  OSHA Estimate.
----------------------------------------------------------------------------------------------------------------
                                                  Recordkeeping
----------------------------------------------------------------------------------------------------------------
Sectors 23 and 31-33                    National................             64.3  OSHA, 2023.
All Other Core Industries.............  National................             50.0  OSHA Estimate.
All Other Non-Core Industries.........  National................             90.0  OSHA Estimate.
----------------------------------------------------------------------------------------------------------------
\a\ OSHA assumes that all employers will need to develop a HIIPP, either by creating a new HIIPP or reviewing
  and updating an existing HIIPP to comply with the proposed standard. More discussion of the calculation of
  HIIPP total costs can be found in section VIII.C.V.B.
\b\ The California State rule only covers select industries within sector 11. Covered agricultural sectors
  include NAICS 1111, 1112, 1113, 1114, 1119, 1121, 1122, 1123, 1124, 1125, 1129, 1151, and 1152.
\c\ California's standard specifies that 6-digit NAICS 213111, 213112, and 561730 need to follow the
  requirements of that rule. Since OSHA analyzes costs and economic impacts for this proposed standard at the 4-
  digit NAICS level, OSHA assumes that only a subset of NAICS 2131 and 5617 in California are already compliant
  with the requirements of OSHA's proposed standard. For NAICS 2131, OSHA assumes that 40 percent of NAICS 2131
  are already compliant (since NAICS 213111 and 213112 represent two of the five 6-digit NAICS within the 4-
  digit NAICS 2131). For NAICS 5617, OSHA assumes that 20 percent of NAICS 5617 are already compliant (since
  NAICS 561730 represents one of the five 6-digit NAICS industries within the 4-digit NAICS 5617). Using these
  assumptions, 60 percent of NAICS 2131 and 80 percent of NAICS 5617 are considered non-compliant.
\d\ Only covers NAICS industry groups 1111, 1112, 1113, 1114, 1119, 1121, 1122, 1123, 1151, and 1152 within
  sector 11.
\e\ Compliance with the effective communication provision of the proposed standard requires employers to
  maintain two-way communication with employees and to regularly communicate with employees. For the purposes of
  this cost analysis, OSHA assumes that 50 percent of employers are currently compliant with the provision. OSHA
  also assumes that half of the remaining non-compliant employers currently engage in one-way communication
  (from supervisor to employee) and would only incur costs for the employee's time communicating with or
  responding to the supervisor, which is reflected in the different non-compliance estimates (for employer and
  supervisor) for effective communication.

B. Cost Savings
    OSHA also considers potential cost savings from the proposed 
standard as a result of requiring employers to provide employees if-
needed or scheduled rest breaks (see appendix A at the end of this 
section for additional details on the assumptions and estimates 
discussed in this section). The best available evidence indicates that 
when employees are exposed to heat and are not allowed to take rest 
breaks or adjust their work hours, they must pace themselves (i.e., 
work more slowly) to counteract the effects of heat exposure. OSHA has 
preliminarily determined that when employees are offered rest breaks, 
cost savings will accrue to employers who are currently noncompliant 
with the rest break requirements because their employees will work more 
efficiently (i.e., pace themselves less) during work time not spent on 
rest breaks. For the purposes of this analysis, OSHA assumes that when 
calculating the unit cost of rest break requirements, these accrued 
cost savings partially offset the wage cost of the employee's time 
spent in required rest breaks.
    OSHA has estimated how many minutes of work time are lost due to 
employees pacing themselves when the heat index is equal to the initial 
and high heat triggers.\51\ OSHA bases these

[[Page 70830]]

estimates on empirical studies and assumed that the employees in these 
studies represent a nationwide average employee (for any State, 
industry, type of worksite, etc.). Some studies included employees who 
took no rest breaks. Some studies included employees who took only if-
needed rest breaks but not scheduled rest breaks, and others included 
employees who took both if-needed and scheduled rest breaks. OSHA found 
that there was a decrease in pacing among employees who took if-needed 
rest breaks and a greater decrease in pacing among those who took 
scheduled rest breaks as well as if-needed rest breaks, as compared 
with employees who took no rest breaks. Reductions in pacing at the 
initial heat trigger from adding if-needed rest breaks and reductions 
in pacing at the high heat trigger from adding scheduled rest breaks 
are translated into equivalent minutes of work time saved as a share of 
the full unit time-cost of these rest breaks, which are then monetized 
to derive total labor costs saved for employers.
---------------------------------------------------------------------------

    \51\ The extent of labor productivity loss due to pacing is 
evaluated when the heat index is equal to the initial or high heat 
triggers. However, the annual number of work hours used in the 
calculation of total labor cost savings from the required rest 
breaks capture work hours when the heat index is at or above the 
triggers (see discussion of temperature data in the following 
section VIII.C.II.C.). That is, in the calculation of the total 
labor cost savings, for example, a worker exposed to 95 [deg]F heat 
index is assumed to lose the same amount of labor productivity as a 
worker exposed to 90 [deg]F heat index (the high heat trigger). This 
discrepancy and other simplifying assumptions would result in 
potential misestimate of labor productivity losses from pacing and 
therefore potential misestimate of total labor cost savings, as 
discussed in more detail in appendix A.
---------------------------------------------------------------------------

C. Temperature
    Some of the requirements of the proposed standard would only be 
required when the heat index meets or exceeds a certain heat trigger 
(i.e., the initial heat trigger at 80 [deg]F or the high heat trigger 
at 90 [deg]F). Requirements dependent on the heat index meeting or 
exceeding certain triggers include, among other things:
     Rest breaks (at both the initial and high heat triggers),
     Acclimatization (at the initial heat trigger),
     Effective communication (initial heat trigger),
     Observation for signs and symptoms (high heat trigger), 
and
     Hazard Alert (high heat trigger).
    In order to calculate the number of times these costs would be 
incurred by entities on a state-by-state basis, OSHA used heat index 
data from the NOAA Local Climatological Data (LCD) for 2020 through 
2022 (NOAA, 2023b). The LCD data included heat index measurements on an 
hourly basis for NWS stations across the country. Due to limited data 
availability, OSHA reviewed a subset of 245 weather stations, 
ultimately analyzing 238 stations for the calculation. For each 
station, OSHA determined the number of workday \52\ hours that met or 
exceeded each of the heat triggers within each shift type as outlined 
in Section VIII.B., Profile of Affected Industries. From here, OSHA 
took the average of the number of workday hours meeting or exceeding 
each of the heat triggers across stations in each State.\53\ OSHA 
excluded seven of the 245 stations for which 10 percent or more of all 
heat index measurements across all three years of data analyzed were 
missing.\54\ OSHA also evaluated the temperature data to identify 
States with relatively low levels of humidity \55\ (Arizona, Nevada, 
New Mexico, and Utah) to inform costs related to dehumidification. OSHA 
used outdoor weather data as a proxy for high heat conditions in indoor 
settings without adequate climate control. Logically, where a building 
does not have air conditioning, there is a correlation between the 
temperature indoors and the temperature outdoors. This may overstate or 
understate the effects of outdoor temperature on indoor temperatures. A 
well-insulated building without air conditioning may be cooler than the 
outside environment, but a poorly insulated, poorly ventilated building 
that absorbs considerable direct sunlight may be hotter. Even though 
exposure to process heat may be exacerbated by outdoor temperatures 
(e.g., on a hot day existing climate control may be inadequate in a hot 
kitchen), there may be instances where exposure to process heat occurs 
on relatively cool days. The agency lacks data to make a finer estimate 
than using outdoor weather as a proxy for indoor heat conditions but 
welcomes data and suggestions for improved estimation methodology. The 
results of this analysis are presented in table VIII.C.5.
---------------------------------------------------------------------------

    \52\ Workday hours in the LCD data are defined as hours on 
weekdays Monday through Friday for each shift type.
    \53\ OSHA acknowledges that this may be imprecise in states 
where the climate varies widely between different parts of the 
state. However, the agency lacks data that would allow for employers 
and employees to be more precisely located within a given state. 
OSHA welcomes comment on this issue and suggestions for 
methodologies to more precisely represent employee exposure within 
States.
    \54\ Based on this methodology, seven stations were excluded: 
McGrath, AK; St. Paul Island, AK; North Little Rock, AR; Eureka, CA; 
Marquette, MI; Minneapolis, MN; and Mt. Washington, NH.
    \55\ OSHA acknowledges that due to intrastate variation in 
climatic conditions, this method may underestimate the number of 
geographic areas that have relatively low humidity.

                                  Table VIII.C.5--Average Annual Hours Exceeding Heat Triggers by State and Work Shift
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                   Daytime shift                   Evening shift                  Overnight Shift
                                                         -----------------------------------------------------------------------------------------------
                          State                            Initial heat      High heat     Initial heat      High heat     Initial heat      High heat
                                                              trigger         trigger         trigger         trigger         trigger         trigger
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaska..................................................               2               0               2               0               0               0
Alabama.................................................             766             372             347              93             101              15
American Samoa \a\......................................           1,481             231             576              11             168               0
Arkansas................................................             674             376             498             218             145              15
Arizona.................................................             701             321             536             233             239              55
California..............................................             452             158             256              75              41               0
Colorado................................................             401              61             155              15               8               0
Connecticut.............................................             312              87             152              22              22               0
District of Columbia \b\................................             535             236             278              75              68               2
Delaware................................................             457             182             245              55              54               3
Florida.................................................           1,259             669             781             273             440             103
Georgia.................................................             740             339             393             115              49               1
Guam \a\................................................           1,481             231             576              11             168               0
Hawaii..................................................           1,481             231             576              11             168               0
Iowa....................................................             389             119             214              51              24               1
Idaho...................................................             347              86             237              49              15               0
Illinois................................................             446             123             205              44              36               2
Indiana.................................................             413             113             214              43              28               2
Kansas..................................................             565             242             334             108              57               1

[[Page 70831]]

 
Kentucky................................................             474             158             272              67              42               4
Louisiana...............................................             925             516             585             220             310              61
Massachusetts...........................................             225              61              96              15              22               1
Maryland................................................             539             243             286              77              68               0
Maine...................................................             150              30              42               4               6               0
Michigan................................................             243              35             120              13               6               0
Minnesota...............................................             186              29              78              10               5               0
Missouri................................................             546             214             325              98              75               7
Mississippi.............................................             789             420             389             132             107              15
Montana.................................................             250              39             141              17               2               0
North Carolina..........................................             566             222             297              72              51               4
North Dakota............................................             270              55             163              29               7               0
Nebraska................................................             482             169             286              79              30               1
New Hampshire...........................................             248              68              93              13               8               0
New Jersey..............................................             451             176             243              60              66               5
New Mexico..............................................             579             125             304              41              33               0
Nevada..................................................             557             189             328              99             130              14
New York................................................             256              48             106               9              17               1
Northern Mariana Islands \a\............................           1,481             231             576              11             168               0
Ohio....................................................             357              73             179              26              12               0
Oklahoma................................................             643             334             456             182             132              10
Oregon..................................................             245              56             141              28               4               0
Pennsylvania............................................             342              87             184              31              23               1
Puerto Rico.............................................           1,942           1,115           1,604             502           1,104             126
Rhode Island............................................             304             108             118              23              23               1
South Carolina..........................................             687             301             361              92              73               3
South Dakota............................................             377              96             203              44              18               0
Tennessee...............................................             571             214             334              88              63               7
Texas...................................................             908             498             676             277             279              38
Utah....................................................             489             136             368              71              55               0
U.S. Virgin Islands \c\.................................           1,942           1,115           1,604             502           1,104             126
Virginia................................................             532             230             270              74              67               4
Vermont.................................................             229              46             115              12              15               0
Washington..............................................             170              36              94              16               5               0
Wisconsin...............................................             310              68             145              26              22               1
West Virginia...........................................             318              58             143              23               4               0
Wyoming.................................................             323              28             110               5               3               0
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source: NOAA, 2023b.
\a\ The NOAA data OSHA used did not have data available for American Samoa, Guam, and the Northern Mariana Islands. Estimates for these island areas are
  set equal to Hawaii's estimates.
\b\ The NOAA data OSHA used did not have data available for the District of Columbia. These estimates reflect the midpoint between Maryland and
  Virginia's estimates presented in this table.
\c\ The NOAA data OSHA used did not have data available for the U.S. Virgin Islands. Estimates for the USVI are set equal to Puerto Rico's estimates
  given their relative proximity.

D. Heat-Related Illnesses--Counts and Incidence Rates
    The provisions of the proposed standard addressing Heat Illness and 
Emergency Response and Planning would require establishments to develop 
and implement a plan to treat employees experiencing heat-related 
illnesses, including heat emergencies. The proposed standard requires 
additional actions for employers when the heat-related illness is 
considered a heat emergency; therefore, it is important to estimate 
separately the incidents of heat-related illnesses that are heat 
emergencies and those that are not heat emergencies. Using the methods 
detailed in Section VIII.E., Benefits, OSHA estimated the average 
expected annual number of heat-related illnesses by industry sector 
after the implementation of the proposed standard, including 
adjustments for effectiveness and undercount as described below. Using 
the estimates of heat-related fatal and non-fatal illnesses by industry 
sector from the Bureau of Labor Statistics (BLS) Census of Fatal 
Occupational Injuries (CFOI) (BLS, 2024c) and Survey of Occupational 
Injuries and Illnesses (SOII) from 2011-2022 (BLS, 2023b), OSHA assumed 
an undercount by a factor of 7.5 for non-fatal heat-related illnesses 
and 3 for fatal heat-related illnesses. As also discussed in Section 
V.C., Risk Reduction and Section VIII.E., Benefits, OSHA also assumed 
an effectiveness rate of 95 percent in reducing heat-related fatal 
illnesses and 65 percent for non-fatal illnesses. Finally, since costs 
are dependent on the severity of illness, OSHA assumed that 5.3 percent 
\56\ of heat-related illnesses are emergencies, and all others are 
considered non-emergencies for this analysis. Then, the number of 
estimated incidents for each sector was divided by the number of 
establishments deemed in-scope of the proposed standard to calculate 
the estimated per-establishment incident rate for each sector. OSHA 
welcomes feedback on the data, assumptions, and methods used to 
estimate the number of heat-related illnesses (emergencies and non-
emergencies) by sector, as well as the per-establishment incidence 
rates by sector.
---------------------------------------------------------------------------

    \56\ OSHA estimated the percentage of heat-related illnesses 
that would be considered emergencies using Harduar Morano and 
Watkins (2017). Using their results reported in table 2 in that 
paper, OSHA calculated the percentage of all HRIs reviewed 
(emergency room visits, hospitalizations, and deaths) that were 
coded as heat stroke (5.3 percent).
---------------------------------------------------------------------------

    Table VIII.C.6. shows the total estimated number of heat-related 
illness emergencies and non-emergencies anticipated annually with the 
proposed standard in place for each sector, as well as per-
establishment incidence rates for each sector.\57\
---------------------------------------------------------------------------

    \57\ This assumes that rates in the future will be the same as 
rates in the recent past. This may be inaccurate if rates are 
reduced due to the efficacy of this proposed standard or if rates 
increase if more workers are exposed to hot environments.

---------------------------------------------------------------------------

[[Page 70832]]

    OSHA welcomes feedback on the assumptions, methods of estimation, 
and data used to estimate per-establishment incidence rates 
(emergencies and non-emergencies) for each sector. OSHA acknowledges 
the possibility that there may be variability in underreporting by 
industry sector, occupation, or some other measure and welcomes 
additional data or information on that possibility.

          Table VIII.C.6.--Summary of Heat-Related Illnesses--Non-Emergencies and Emergencies by Sector
----------------------------------------------------------------------------------------------------------------
                                              Non-emergencies                           Emergencies
             Sector              -------------------------------------------------------------------------------
                                   Annual Incidents     Incidence rate     Annual incidents     Incidence rate
----------------------------------------------------------------------------------------------------------------
11..............................                 249               0.002                  16               0.000
21..............................                 120               0.006                   8               0.000
22..............................                  68               0.004                   4               0.000
23..............................               1,270               0.002                  80               0.000
31-33...........................               1,056               0.007                  62               0.000
42..............................                 325               0.008                  19               0.000
44-45...........................                 456               0.003                  26               0.000
48-49...........................                 808               0.004                  46               0.000
51..............................                 236               0.011                  14               0.001
52..............................                  27               0.000                   2               0.000
53..............................                 141               0.003                   8               0.000
54..............................                 102               0.001                   6               0.000
55..............................                  51               0.007                   3               0.000
56..............................                 729               0.013                  44               0.001
61..............................                  23               0.001                   1               0.000
62..............................                 207               0.005                  12               0.000
71..............................                 112               0.001                   7               0.000
72..............................                 255               0.001                  15               0.000
81..............................                 259               0.001                  15               0.000
92..............................               1,643               0.317                  94               0.018
----------------------------------------------------------------------------------------------------------------
Source: OSHA estimate derived from BLS, 2023b, and BLS, 2024c.

III. Labor Rates
    Labor costs associated with the proposed standard are derived using 
wage data from BLS' cross-industry Occupational Employment and Wage 
Statistics (OEWS) for May 2022 (BLS, 2023c). For the purposes of this 
cost analysis, two employee types are used to represent affected 
employees: ``designated person'' and ``at-risk worker.'' For each 
industry sector, OSHA estimated the average hourly wage for these two 
employee types.
    For the purpose of estimating costs, wages for the designated 
person position were derived by filtering the OEWS data for occupations 
that included ``Manager,'' ``Supervisor,'' or ``Director'' in their 
Standard Occupational Classification (SOC) title and then reviewing 
those occupations to identify those that may be expected to directly 
supervise employees exposed to heat-related hazards.\58\ Occupations 
used in the analysis include those (1) that have detailed occupation 
codes (i.e., six-digit SOC code), (2) deemed to supervise potentially 
at-risk employees, (3) with recorded employment numbers, and (4) with 
recorded median hourly wage data. For these occupations, OSHA 
calculated the percentage of each industry sector's total available 
employment that each detailed occupation represented. OSHA then 
calculated the weighted average hourly wage for each sector using the 
product of these percentages and the corresponding median hourly wage 
estimates from the OEWS. OSHA assumes that the average hourly wages 
calculated for each represent those for designated workers. OSHA 
acknowledges that this method of estimation may lead to an overestimate 
in wage costs as the designated person does not necessarily have to be 
a supervisor, manager, or director in all cases. For this analysis, 
OSHA also uses these wages developed for designated persons to 
represent supervisors' wages. OSHA welcomes feedback on the 
assumptions, methods, and data used to estimate the wages of a 
designated person.
---------------------------------------------------------------------------

    \58\ Although for purposes of this cost analysis OSHA 
distinguishes between a ``designated person'' and ``at-risk 
workers,'' this terminology is not intended to suggest that 
supervisors or managers who supervise workers exposed to heat 
related hazards are not themselves also ``at risk'' when exposed to 
the same hazards.
---------------------------------------------------------------------------

    Wages for at-risk workers are calculated using a process similar to 
the process used to calculate the number of affected employees in 
section VIII.B.IV.A. The main differences for determining the wages for 
at-risk workers are that the methodology for estimating wages uses OEWS 
data at the 2-digit NAICS sector level instead of the 4-digit NAICS 
industry group level and that some occupations that are otherwise used 
to determine the percentage of employees that are exposed to heat-
related hazards are not included for the wage calculation because the 
relevant employment and/or wage data are undisclosed. OSHA calculated 
the percentage of a given sector's at-risk employment made up by each 
SOC code and multiplied this percentage by the hourly median wage from 
OEWS. Finally, OSHA summed these products for each sector to estimate 
the weighted average hourly wage for at-risk workers in each sector.
    OSHA uses the estimated hourly wage rates to calculate a loaded 
wage rate that includes three types of cost: hourly base wage, fringe 
benefits, and overhead costs.
    For the calculation of fringe benefit costs, OSHA used data from 
BLS' Employer Costs for Employee Compensation (ECEC) for December 2023 
(BLS, 2024b) to determine that fringe benefits can be estimated as 45 
percent of base wages or 31.1 percent of total compensation.
    OSHA also accounts for indirect expenses that cannot be tied to 
producing a specific product or service, called overhead costs. Common

[[Page 70833]]

examples include rent, utilities, and office equipment. There is no 
consensus on the cost elements that fit this definition and the lack of 
a common definition has led to a wide range of overhead estimates. 
Consequently, the treatment of overhead costs needs to be case-
specific. In this analysis, OSHA used an overhead rate of 17 percent of 
base wages (EPA, 2002; Rice, 2002). This 17 percent rate is based on an 
estimate of overhead costs for safety and health professionals in large 
private organizations. This overhead rate is consistent with, for 
example, the overhead rate used in the Final Economic Analysis (FEA) in 
support of OSHA's 2023 final rule amending its occupational injury and 
illness recordkeeping (88 FR 47254) and the economic feasibility 
analysis in support of OSHA's 2021 Healthcare Emergency Temporary 
Standard (Healthcare ETS).\59\ (86 FR 32376). OSHA expects that this 
rate is likely an overestimate in this context, as this reflects a 
component of average overhead; in this case, however, the agency 
anticipates that, for example, designated persons and at-risk workers 
will be able to work within the general physical infrastructure in 
which they currently operate. A rate of 17 percent of base wages is 
equivalent to 11.71 percent of the hourly wage rate with fringe 
applied.\60\
---------------------------------------------------------------------------

    \59\ See the FEAs in in the Improved Tracking of Workplace 
Injuries and Illnesses FEA (https://www.govinfo.gov/content/pkg/FR-2023-07-21/pdf/2023-15091.pdf) and the feasibility analysis support 
of OSHA's 2021 Healthcare ETS (86 FR 32376) (https://www.govinfo.gov/content/pkg/FR-2021-06-21/pdf/2021-12428.pdf).The 
methodology was modeled after an approach used by the EPA. More 
information on this approach can be found at: U.S. Environmental 
Protection Agency, ``Wage Rates for Economic Analyses of the Toxics 
Release Inventory Program,'' June 10, 2002 (Ex. 2066). This analysis 
itself was based on a survey of several large chemical manufacturing 
plants: Heiden Associates, Final Report: A Study of Industry 
Compliance Costs Under the Final Comprehensive Assessment 
Information Rule, Prepared for the Chemical Manufacturers 
Association, December 14, 1989, Ex. 2065.
    \60\ The fringe-adjusted overhead rate, 11.71%, is calculated as 
68.9 percent * 17 percent, i.e., the percent of wages that are the 
base hourly rate exclusive of fringe (68.9 percent) multiplied by 
the overhead rate as a percentage of base hourly wages (17 percent).
---------------------------------------------------------------------------

    To calculate the fully loaded hourly labor cost, OSHA added the 
three components together: base wages + fringe benefits (31.1 percent 
of total compensation) + applicable overhead (17 percent of base 
wages). Table VIII.C.7. shows the loaded hourly wages used in the 
analysis. OSHA welcomes feedback on the assumptions, methods, and data 
used to estimate the wages of a designated person and at-risk worker.

                                 Table VIII.C.7--Wage Rates Used in the Analysis
                                                     [2023$]
----------------------------------------------------------------------------------------------------------------
                                        Median hourly                        Fringe-adjusted     Loaded hourly
               Sector                      wage \a\        Fringe \b\ (%)    overhead \c\ (%)       wage \d\
----------------------------------------------------------------------------------------------------------------
                                                Designated Person
----------------------------------------------------------------------------------------------------------------
11..................................             $30.73               45.0               11.7             $49.83
21..................................              50.76               45.0               11.7              82.31
22..................................              57.93               45.0               11.7              93.94
23..................................              42.26               45.0               11.7              68.53
31-33...............................              43.15               45.0               11.7              69.97
42..................................              42.41               45.0               11.7              68.77
44-45...............................              26.45               45.0               11.7              42.89
48-49...............................              37.37               45.0               11.7              60.59
51..................................              54.75               45.0               11.7              88.78
52..................................              49.94               45.0               11.7              80.98
53..................................              36.94               45.0               11.7              59.91
54..................................              59.00               45.0               11.7              95.67
55..................................              60.81               45.0               11.7              98.62
56..................................              34.51               45.0               11.7              55.97
61..................................              36.68               45.0               11.7              59.49
62..................................              34.49               45.0               11.7             $55.92
71..................................              28.83               45.0               11.7              46.75
72..................................              20.50               45.0               11.7              33.24
81..................................              33.58               45.0               11.7              54.45
92..................................              45.08               45.0               11.7              73.10
----------------------------------------------------------------------------------------------------------------
                                                 At-Risk Worker
----------------------------------------------------------------------------------------------------------------
11..................................              16.53               45.0               11.7              26.80
21..................................              28.65               45.0               11.7              46.46
22..................................              46.58               45.0               11.7              75.53
23..................................              27.10               45.0               11.7              43.95
31-33...............................              22.62               45.0               11.7              36.68
42..................................              26.11               45.0               11.7              42.34
44-45...............................              16.21               45.0               11.7              26.28
48-49...............................              20.52               45.0               11.7              33.27
51..................................              35.48               45.0               11.7              57.54
52..................................              35.92               45.0               11.7              58.24
53..................................              23.09               45.0               11.7              37.44
54..................................              47.08               45.0               11.7              76.34
55..................................              54.28               45.0               11.7              88.02
56..................................              17.00               45.0               11.7              27.56
61..................................              20.15               45.0               11.7              32.68
62..................................              17.56               45.0               11.7              28.48

[[Page 70834]]

 
71..................................              15.55               45.0               11.7              25.21
72..................................              14.88               45.0               11.7              24.13
81..................................              21.17               45.0               11.7              34.33
92..................................              31.28               45.0               11.7              50.72
----------------------------------------------------------------------------------------------------------------
Source: OSHA estimate derived from BLS, 2023c; BLS, 2024b; O*NET, 2023; EPA, 2002; and Rice, 2002.
\a\ Median hourly wage rates are drawn from BLS' sector-level OEWS for May 2022. For the designated person, the
  wages represent a weighted average of wage across SOC codes that would directly supervise potentially at-risk
  workers. For the at-risk worker, the wages reflect weighted averages between SOC codes that are deemed in-
  scope for this proposed standard.
\b\ The fringe rate is drawn from BLS' ECEC for December 2023 (BLS, 2024b).
\c\ The overhead rate is derived from EPA (2002) and Rice (2002).
\d\ The loaded hourly wage = median hourly wage *(1 + fringe rate) * (1 + fringe-adjusted overhead rate).

IV. Estimated Unit Costs of Compliance
    This section presents the estimated unit costs of the proposed 
standard by industry sector and proposed provision. Unless otherwise 
noted in this section, the time estimates for complying with proposed 
provisions are based on OSHA's professional expertise, considering what 
the proposed standard requires and estimates of the hours necessary to 
comply with similar requirements in other OSHA rules. OSHA welcomes 
comment on all estimates discussed here. Additional data or suggestions 
on methodological changes the agency should consider are also welcome.
A. Rule Familiarization
    All employers affected by the proposed standard would need to 
review the requirements under the proposed standard. While some 
employers will read the standard, many will likely rely on compliance 
assistance documents prepared by OSHA or by trade or industry 
associations that will provide the needed information in a simpler 
manner that would take less time to review and digest than the 
regulatory language. OSHA estimates that rule familiarization would 
take a designated person one hour to complete. Table VIII.C.8. shows 
the unit costs for rule familiarization by industry sector.
B. Heat Injury and Illness Prevention Plan (HIIPP)

                                                    Table VIII.C.8--Unit Costs--Rule Familiarization
                                                                         [2023$]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                Sector                       Hours         Unit cost          Labor category                 Basis                    Frequency
--------------------------------------------------------------------------------------------------------------------------------------------------------
11....................................             1.0          $49.83  Designated Person........  Establishment...........  One-Time.
21....................................             1.0           82.31  Designated Person........  Establishment...........  One-Time.
22....................................             1.0           93.94  Designated Person........  Establishment...........  One-Time.
23....................................             1.0           68.53  Designated Person........  Establishment...........  One-Time.
31-33.................................             1.0           69.97  Designated Person........  Establishment...........  One-Time.
42....................................             1.0           68.77  Designated Person........  Establishment...........  One-Time.
44-45.................................             1.0           42.89  Designated Person........  Establishment...........  One-Time.
48-49.................................             1.0           60.59  Designated Person........  Establishment...........  One-Time.
51....................................             1.0           88.78  Designated Person........  Establishment...........  One-Time.
52....................................             1.0           80.98  Designated Person........  Establishment...........  One-Time.
53....................................             1.0           59.91  Designated Person........  Establishment...........  One-Time.
54....................................             1.0           95.67  Designated Person........  Establishment...........  One-Time.
55....................................             1.0           98.62  Designated Person........  Establishment...........  One-Time.
56....................................             1.0           55.97  Designated Person........  Establishment...........  One-Time.
61....................................             1.0           59.49  Designated Person........  Establishment...........  One-Time.
62....................................             1.0           55.92  Designated Person........  Establishment...........  One-Time.
71....................................             1.0           46.75  Designated Person........  Establishment...........  One-Time.
72....................................             1.0           33.24  Designated Person........  Establishment...........  One-Time.
81....................................             1.0           54.45  Designated Person........  Establishment...........  One-Time.
92....................................             1.0           73.10  Designated Person........  Establishment...........  One-Time.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source: OSHA estimate derived from BLS, 2023c; BLS, 2024b; O*NET, 2023; EPA, 2002; and Rice, 2002.

    Under paragraph (c) of the proposed standard, employers must create 
a written HIIPP,\61\ with the input from employees. OSHA acknowledges 
that some employers may already have an existing HIIPP that may only 
need to be modified to comply with the proposed standard. The HIIPP 
must include:
---------------------------------------------------------------------------

    \61\ Employers with 10 or fewer employees do not have to write 
out their HIIPP.
---------------------------------------------------------------------------

     A comprehensive list of the types of work activities 
covered by the plan;
     All policies and procedures necessary to comply with the 
requirements of this proposed standard including those to protect 
employees while wearing vapor-impermeable clothing; and
     Identification of the heat metric (i.e., heat index or wet 
bulb globe temperature) the employer will monitor to identify heat 
hazards.
    Further, the employer must designate one or more heat safety 
coordinators to implement and monitor the HIIPP, make

[[Page 70835]]

the HIIPP readily available to all employees in a language that all 
employees understand, and review the HIIPP whenever a heat-related 
incident occurs those results in death, days away from work, medical 
treatment beyond first aid, or loss of consciousness. The review of the 
HIIPP must occur at least annually.
    For employers with an existing HIIPP in place, OSHA assumes that 
employers will designate someone to review their HIIPP and make any 
modifications necessary to comply with the proposed standard. OSHA 
estimates this process will require 2.5 hours of the designated 
person's time. Employers that do not have an existing HIIPP could 
either choose to use a HIIPP template (for example, one provided by 
OSHA as part of rollout materials or one from a trade organization) or 
write a HIIPP from scratch. Because writing a HIIPP from scratch 
without the help of a template would be considerably more onerous, OSHA 
expects that most employers would not choose this option and would, 
instead, opt to use a template which the agency estimates would require 
approximately six hours of a designated person's time to locate, 
review, identify relevant sections, and fill in worksite-specific 
information on hazards, controls, and procedures. For employers that 
are exempt from writing their HIIPP (i.e., those with ten or less 
employees) OSHA assumes that they will spend four hours using a 
template to guide their creation of a HIIPP. OSHA assumes that five 
percent of employers will have complex or unique situations where a 
template would not be usable. For these employees, OSHA estimates that 
it will take 30 hours of a designated person's time to prepare the 
HIIPP. OSHA welcomes comments and input on these estimates and 
assumptions. The agency would like information and data on how these 
estimates correspond to the costs incurred by employers who have 
developed written HIIPPs, whether the time estimates are reasonable, 
and what method employers have taken when developing their plans.
    Additionally, the proposed standard would require employers to 
review and update the HIIPP periodically. Regardless of how employers 
develop or modify their HIIPPs initially, OSHA estimates that the 
process of reviewing and updating the HIIPP would take the person 
designated on average one hour per year to do so.
    The proposed standard would also require that employers involve 
non-managerial employees in the creation or initial modification of the 
HIIPP, as well as in the process of periodically reviewing and updating 
the HIIPP. OSHA assumes that a representative group of employees (four 
employees per establishment) will take one hour each during the initial 
development of the HIIPP to provide feedback, regardless of whether the 
employer has an existing HIIPP. This same representative group of 
employees would take 20 minutes each during the review and update of 
the HIIPP to provide feedback. OSHA welcomes comments and input on 
these estimates and assumptions. The agency would like information and 
data on how these estimates correspond to the costs incurred by 
employers who have developed written HIIPPs, whether the time estimates 
are reasonable, and what method employers have taken when developing 
their plans.
    Table VIII.C.9. shows the units costs for developing and updating 
the HIIPP by industry sector.

                                           Table VIII.C.9--Unit Costs--Heat Injury and Illness Prevention Plan
                                                                         [2023$]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                Sector                       Hours         Unit cost          Labor category                 Basis                    Frequency
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                Write HIIPP from Scratch
--------------------------------------------------------------------------------------------------------------------------------------------------------
11....................................            30.0       $1,494.92  Designated Person........  Establishment...........  One-Time.
21....................................            30.0        2,469.40  Designated Person........  Establishment...........  One-Time.
22....................................            30.0        2,818.32  Designated Person........  Establishment...........  One-Time.
23....................................            30.0        2,055.78  Designated Person........  Establishment...........  One-Time.
31-33.................................            30.0        2,099.13  Designated Person........  Establishment...........  One-Time.
42....................................            30.0        2,063.18  Designated Person........  Establishment...........  One-Time.
44-45.................................            30.0        1,286.74  Designated Person........  Establishment...........  One-Time.
48-49.................................            30.0        1,817.75  Designated Person........  Establishment...........  One-Time.
51....................................            30.0        2,663.34  Designated Person........  Establishment...........  One-Time.
52....................................            30.0        2,429.29  Designated Person........  Establishment...........  One-Time.
53....................................            30.0        1,797.15  Designated Person........  Establishment...........  One-Time.
54....................................            30.0        2,869.97  Designated Person........  Establishment...........  One-Time.
55....................................            30.0        2,958.49  Designated Person........  Establishment...........  One-Time.
56....................................            30.0        1,678.99  Designated Person........  Establishment...........  One-Time.
61....................................            30.0        1,784.56  Designated Person........  Establishment...........  One-Time.
62....................................            30.0        1,677.73  Designated Person........  Establishment...........  One-Time.
71....................................            30.0        1,402.49  Designated Person........  Establishment...........  One-Time.
72....................................            30.0          997.21  Designated Person........  Establishment...........  One-Time.
81....................................            30.0        1,633.62  Designated Person........  Establishment...........  One-Time.
92....................................            30.0        2,193.10  Designated Person........  Establishment...........  One-Time.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                     Review and Modify HIIPP--Existing Plan in Place
--------------------------------------------------------------------------------------------------------------------------------------------------------
11....................................             2.5          124.58  Designated Person........  Establishment...........  One-Time.
21....................................             2.5          205.78  Designated Person........  Establishment...........  One-Time.
22....................................             2.5          234.86  Designated Person........  Establishment...........  One-Time.
23....................................             2.5          171.31  Designated Person........  Establishment...........  One-Time.
31-33.................................             2.5          174.93  Designated Person........  Establishment...........  One-Time.
42....................................             2.5          171.93  Designated Person........  Establishment...........  One-Time.
44-45.................................             2.5          107.23  Designated Person........  Establishment...........  One-Time.
48-49.................................             2.5          151.48  Designated Person........  Establishment...........  One-Time.
51....................................             2.5          221.94  Designated Person........  Establishment...........  One-Time.
52....................................             2.5          202.44  Designated Person........  Establishment...........  One-Time.
53....................................             2.5          149.76  Designated Person........  Establishment...........  One-Time.

[[Page 70836]]

 
54....................................             2.5          239.16  Designated Person........  Establishment...........  One-Time.
55....................................             2.5          246.54  Designated Person........  Establishment...........  One-Time.
56....................................             2.5          139.92  Designated Person........  Establishment...........  One-Time.
61....................................             2.5          148.71  Designated Person........  Establishment...........  One-Time.
62....................................             2.5          139.81  Designated Person........  Establishment...........  One-Time.
71....................................             2.5          116.87  Designated Person........  Establishment...........  One-Time.
72....................................             2.5           83.10  Designated Person........  Establishment...........  One-Time.
81....................................             2.5          136.14  Designated Person........  Establishment...........  One-Time.
92....................................             2.5          182.76  Designated Person........  Establishment...........  One-Time.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                   Use HIIPP Template
--------------------------------------------------------------------------------------------------------------------------------------------------------
11....................................             6.0          298.98  Designated Person........  Establishment...........  One-Time.
21....................................             6.0          493.88  Designated Person........  Establishment...........  One-Time.
22....................................             6.0          563.66  Designated Person........  Establishment...........  One-Time.
23....................................             6.0          411.16  Designated Person........  Establishment...........  One-Time.
31-33.................................             6.0          419.83  Designated Person........  Establishment...........  One-Time.
42....................................             6.0          412.64  Designated Person........  Establishment...........  One-Time.
44-45.................................             6.0          257.35  Designated Person........  Establishment...........  One-Time.
48-49.................................             6.0          363.55  Designated Person........  Establishment...........  One-Time.
51....................................             6.0          532.67  Designated Person........  Establishment...........  One-Time.
52....................................             6.0          485.86  Designated Person........  Establishment...........  One-Time.
53....................................             6.0          359.43  Designated Person........  Establishment...........  One-Time.
54....................................             6.0          573.99  Designated Person........  Establishment...........  One-Time.
55....................................             6.0          591.70  Designated Person........  Establishment...........  One-Time.
56....................................             6.0          335.80  Designated Person........  Establishment...........  One-Time.
61....................................             6.0          356.91  Designated Person........  Establishment...........  One-Time.
62....................................             6.0          335.55  Designated Person........  Establishment...........  One-Time.
71....................................             6.0          280.50  Designated Person........  Establishment...........  One-Time.
72....................................             6.0          199.44  Designated Person........  Establishment...........  One-Time.
81....................................             6.0          326.72  Designated Person........  Establishment...........  One-Time.
92....................................             6.0          438.62  Designated Person........  Establishment...........  One-Time.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                    No Written HIIPP
--------------------------------------------------------------------------------------------------------------------------------------------------------
11....................................             4.0          199.32  Designated Person........  Establishment...........  One-Time.
21....................................             4.0          329.25  Designated Person........  Establishment...........  One-Time.
22....................................             4.0          375.78  Designated Person........  Establishment...........  One-Time.
23....................................             4.0          274.10  Designated Person........  Establishment...........  One-Time.
31-33.................................             4.0          279.88  Designated Person........  Establishment...........  One-Time.
42....................................             4.0          275.09  Designated Person........  Establishment...........  One-Time.
44-45.................................             4.0          171.57  Designated Person........  Establishment...........  One-Time.
48-49.................................             4.0          242.37  Designated Person........  Establishment...........  One-Time.
51....................................             4.0          355.11  Designated Person........  Establishment...........  One-Time.
52....................................             4.0          323.91  Designated Person........  Establishment...........  One-Time.
53....................................             4.0          239.62  Designated Person........  Establishment...........  One-Time.
54....................................             4.0          382.66  Designated Person........  Establishment...........  One-Time.
55....................................             4.0          394.46  Designated Person........  Establishment...........  One-Time.
56....................................             4.0          223.87  Designated Person........  Establishment...........  One-Time.
61....................................             4.0          237.94  Designated Person........  Establishment...........  One-Time.
62....................................             4.0          223.70  Designated Person........  Establishment...........  One-Time.
71....................................             4.0          187.00  Designated Person........  Establishment...........  One-Time.
72....................................             4.0          132.96  Designated Person........  Establishment...........  One-Time.
81....................................             4.0          217.82  Designated Person........  Establishment...........  One-Time.
92....................................             4.0          292.41  Designated Person........  Establishment...........  One-Time.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                         HIIPP Development Involvement--Employee
--------------------------------------------------------------------------------------------------------------------------------------------------------
11....................................             1.0           26.80  At-Risk Worker...........  Establishment...........  One-Time.
21....................................             1.0           46.46  At-Risk Worker...........  Establishment...........  One-Time.
22....................................             1.0           75.53  At-Risk Worker...........  Establishment...........  One-Time.
23....................................             1.0           43.95  At-Risk Worker...........  Establishment...........  One-Time.
31-33.................................             1.0           36.68  At-Risk Worker...........  Establishment...........  One-Time.
42....................................             1.0           42.34  At-Risk Worker...........  Establishment...........  One-Time.
44-45.................................             1.0           26.28  At-Risk Worker...........  Establishment...........  One-Time.
48-49.................................             1.0           33.27  At-Risk Worker...........  Establishment...........  One-Time.
51....................................             1.0           57.54  At-Risk Worker...........  Establishment...........  One-Time.
52....................................             1.0           58.24  At-Risk Worker...........  Establishment...........  One-Time.
53....................................             1.0           37.44  At-Risk Worker...........  Establishment...........  One-Time.
54....................................             1.0           76.34  At-Risk Worker...........  Establishment...........  One-Time.
55....................................             1.0           88.02  At-Risk Worker...........  Establishment...........  One-Time.

[[Page 70837]]

 
56....................................             1.0           27.56  At-Risk Worker...........  Establishment...........  One-Time.
61....................................             1.0           32.68  At-Risk Worker...........  Establishment...........  One-Time.
62....................................             1.0           28.48  At-Risk Worker...........  Establishment...........  One-Time.
71....................................             1.0           25.21  At-Risk Worker...........  Establishment...........  One-Time.
72....................................             1.0           24.13  At-Risk Worker...........  Establishment...........  One-Time.
81....................................             1.0           34.33  At-Risk Worker...........  Establishment...........  One-Time.
92....................................             1.0           50.72  At-Risk Worker...........  Establishment...........  One-Time.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                 Review and Update HIIPP
--------------------------------------------------------------------------------------------------------------------------------------------------------
11....................................             1.0           49.83  Designated Person........  Establishment...........  Annual.
21....................................             1.0           82.31  Designated Person........  Establishment...........  Annual.
22....................................             1.0           93.94  Designated Person........  Establishment...........  Annual.
23....................................             1.0           68.53  Designated Person........  Establishment...........  Annual.
31-33.................................             1.0           69.97  Designated Person........  Establishment...........  Annual.
42....................................             1.0           68.77  Designated Person........  Establishment...........  Annual.
44-45.................................             1.0           42.89  Designated Person........  Establishment...........  Annual.
48-49.................................             1.0           60.59  Designated Person........  Establishment...........  Annual.
51....................................             1.0           88.78  Designated Person........  Establishment...........  Annual.
52....................................             1.0           80.98  Designated Person........  Establishment...........  Annual.
53....................................             1.0           59.91  Designated Person........  Establishment...........  Annual.
54....................................             1.0           95.67  Designated Person........  Establishment...........  Annual.
55....................................             1.0           98.62  Designated Person........  Establishment...........  Annual.
56....................................             1.0           55.97  Designated Person........  Establishment...........  Annual.
61....................................             1.0           59.49  Designated Person........  Establishment...........  Annual.
62....................................             1.0           55.92  Designated Person........  Establishment...........  Annual.
71....................................             1.0           46.75  Designated Person........  Establishment...........  Annual.
72....................................             1.0           33.24  Designated Person........  Establishment...........  Annual.
81....................................             1.0           54.45  Designated Person........  Establishment...........  Annual.
92....................................             1.0           73.10  Designated Person........  Establishment...........  Annual.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                      HIIPP Review and Update Involvement--Employee
--------------------------------------------------------------------------------------------------------------------------------------------------------
11....................................            0.33            8.93  At-Risk Worker...........  Establishment...........  Annual.
21....................................            0.33           15.49  At-Risk Worker...........  Establishment...........  Annual.
22....................................            0.33           25.18  At-Risk Worker...........  Establishment...........  Annual.
23....................................            0.33           14.65  At-Risk Worker...........  Establishment...........  Annual.
31-33.................................            0.33           12.23  At-Risk Worker...........  Establishment...........  Annual.
42....................................            0.33           14.11  At-Risk Worker...........  Establishment...........  Annual.
44-45.................................            0.33            8.76  At-Risk Worker...........  Establishment...........  Annual.
48-49.................................            0.33           11.09  At-Risk Worker...........  Establishment...........  Annual.
51....................................            0.33           19.18  At-Risk Worker...........  Establishment...........  Annual.
52....................................            0.33           19.41  At-Risk Worker...........  Establishment...........  Annual.
53....................................            0.33           12.48  At-Risk Worker...........  Establishment...........  Annual.
54....................................            0.33           25.45  At-Risk Worker...........  Establishment...........  Annual.
55....................................            0.33           29.34  At-Risk Worker...........  Establishment...........  Annual.
56....................................            0.33            9.19  At-Risk Worker...........  Establishment...........  Annual.
61....................................            0.33           10.89  At-Risk Worker...........  Establishment...........  Annual.
62....................................            0.33            9.49  At-Risk Worker...........  Establishment...........  Annual.
71....................................            0.33            8.40  At-Risk Worker...........  Establishment...........  Annual.
72....................................            0.33            8.04  At-Risk Worker...........  Establishment...........  Annual.
81....................................            0.33           11.44  At-Risk Worker...........  Establishment...........  Annual.
92....................................            0.33           16.91  At-Risk Worker...........  Establishment...........  Annual.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source: OSHA estimate derived from BLS, 2023c; BLS, 2024b; O*NET, 2023; EPA, 2002; and Rice, 2002.

C. Identifying Heat Hazards
    The proposed standard would require employers to assess where and 
when employees are exposed to temperatures at or above the initial and 
high heat triggers. For outdoor work sites, the proposed standard would 
require employers to monitor heat conditions using either local heat 
index forecasts or on-site measurement of heat index or wet bulb globe 
temperature (WBGT). OSHA assumes that all outdoor employers without 
current monitoring practices will choose the option to monitor local 
forecasts since the time necessary to do so would be minimal (and many 
individuals check local forecasts regularly without regard to this 
proposed standard). Employers may have a designated person at each work 
site track local forecasts of ambient temperature and humidity provided 
by the National Weather Service (NWS) (or others) to determine the 
daily maximum heat index, which the employer would then use to 
determine which protocols are triggered, if any. For this analysis, 
OSHA assumes that employers, on average, will take approximately 15 
seconds twice a day to monitor the local forecast via a smart phone 
app.
    Alternatively, employers can set up monitoring devices as close as 
possible to the work area to conduct on-site monitoring. Employers may 
choose between measuring the heat index or

[[Page 70838]]

WBGT using monitoring devices. Employers with indoor work sites do not 
have the option of monitoring local weather forecasts. The first 
approach, measuring the heat index, would require the employer to 
designate someone to take measurements of the heat index, or to measure 
separately the ambient temperature and humidity to calculate heat index 
(if needed, using the OSHA-NIOSH Heat Safety Tool App as a calculator 
or the online calculator available from the NWS). OSHA estimates that 
on average, it will take the designated person 1 minute each time they 
measure the heat index or ambient temperature and humidity, including 
calculating the heat index (e.g., by consulting the OSHA-NIOSH App or 
NWS's online calculator). OSHA also assumes that measurements will be 
taken on average twice per work day (260 days per year) and that 
employers using this approach will use a temperature and humidity 
logger that is capable of automatically uploading relevant 
environmental information for recordkeeping purposes. OSHA assumes that 
the designated person will spend 15 minutes to read the logger's user 
manual. OSHA also assumes that all indoor employers without current 
monitoring in place will adopt this option.
    The second approach, measuring the WBGT, would require the employer 
to designate someone to take measurements of wet bulb globe 
temperature. This approach would require the purchase of one WBGT 
thermometer for each worksite and some of a designated person's time to 
read the thermometer manual. OSHA assumes that no employers will adopt 
this option, however some employers may already be using this method. 
Those employers can continue to use this method under this proposed 
standard and are not estimated to incur any costs to do so since they 
are already in compliance.
    Employers with indoor work sites would be required to conduct a 
hazard evaluation to identify the work areas where there is a 
reasonable expectation that employees are or may be exposed to heat at 
or above the initial heat trigger. OSHA estimates that conducting the 
hazard evaluation would require about 3 hours in total.
    Employers would be required to seek the input and involvement of 
non-managerial employees and their representatives, if any, when 
evaluating the work site to identify work areas with a reasonable 
expectation of exposures at or above the initial heat trigger and in 
developing and updating monitoring plans. The time to develop 
monitoring plans, as well as the time for employee input, is already 
captured within the time estimate for HIIPP development and employee 
involvement in HIIPP development. Otherwise, OSHA estimates that 
employee input for evaluating work sites would require 15 minutes per 
employee providing input. For this analysis, OSHA assumes four 
employees per establishment would provide input.
    The proposed standard would allow employers to forgo taking 
measurements if they assume that a work area meets or exceeds both heat 
triggers. Employers that elect to do this would not incur monitoring 
costs. These employers would be required to comply with all control 
measures required at both the initial and high heat triggers as though 
they took a measurement that meets or exceeds the high heat trigger. 
OSHA assumes that no employers will newly adopt this option, because 
the Annual. monitoring cost per establishment is relatively low 
compared to the costs to implement other parts of the rule that would 
be required for employers choosing this option. Most employers will 
find it less expensive to monitor temperatures and implement the 
requirements when a trigger is met or exceeded. OSHA welcomes feedback 
on this assumption, specifically the types of employers that might 
forgo monitoring and assume that their workplace is at or above both 
heat triggers.
    Table VIII.C.10. shows the labor-based unit costs for identifying 
heat hazards by industry sector. Table VIII.C.11. shows the equipment 
costs that employers would incur to comply with the requirements for 
identifying heat hazards.

                                            Table VIII.C.10--Labor-Based Unit Costs--Identifying Heat Hazards
                                                                         [2023$]
--------------------------------------------------------------------------------------------------------------------------------------------------------
               Sector                      Hours         Unit cost         Labor category               Basis                       Frequency
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                            Outdoor Environmental Monitoring
--------------------------------------------------------------------------------------------------------------------------------------------------------
11..................................             2.2         $107.97  Designated Person......  Establishment..........  Annual.
21..................................             2.2          178.35  Designated Person......  Establishment..........  Annual.
22..................................             2.2          203.55  Designated Person......  Establishment..........  Annual.
23..................................             2.2          148.47  Designated Person......  Establishment..........  Annual.
31-33...............................             2.2          151.60  Designated Person......  Establishment..........  Annual.
42..................................             2.2          149.01  Designated Person......  Establishment..........  Annual.
44-45...............................             2.2           92.93  Designated Person......  Establishment..........  Annual.
48-49...............................             2.2          131.28  Designated Person......  Establishment..........  Annual.
51..................................             2.2          192.35  Designated Person......  Establishment..........  Annual.
52..................................             2.2          175.45  Designated Person......  Establishment..........  Annual.
53..................................             2.2          129.79  Designated Person......  Establishment..........  Annual.
54..................................             2.2          207.28  Designated Person......  Establishment..........  Annual.
55..................................             2.2          213.67  Designated Person......  Establishment..........  Annual.
56..................................             2.2          121.26  Designated Person......  Establishment..........  Annual.
61..................................             2.2          128.88  Designated Person......  Establishment..........  Annual.
62..................................             2.2          121.17  Designated Person......  Establishment..........  Annual.
71..................................             2.2          101.29  Designated Person......  Establishment..........  Annual.
72..................................             2.2           72.02  Designated Person......  Establishment..........  Annual.
81..................................             2.2          117.98  Designated Person......  Establishment..........  Annual.
92..................................             2.2          158.39  Designated Person......  Establishment..........  Annual.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                             Indoor Environmental Monitoring
--------------------------------------------------------------------------------------------------------------------------------------------------------
11..................................             8.7          431.87  Designated Person......  Establishment..........  Annual.
21..................................             8.7          713.38  Designated Person......  Establishment..........  Annual.

[[Page 70839]]

 
22..................................             8.7          814.18  Designated Person......  Establishment..........  Annual.
23..................................             8.7          593.89  Designated Person......  Establishment..........  Annual.
31-33...............................             8.7          606.42  Designated Person......  Establishment..........  Annual.
42..................................             8.7          596.03  Designated Person......  Establishment..........  Annual.
44-45...............................             8.7          371.72  Designated Person......  Establishment..........  Annual.
48-49...............................             8.7          525.13  Designated Person......  Establishment..........  Annual.
51..................................             8.7          769.41  Designated Person......  Establishment..........  Annual.
52..................................             8.7          701.80  Designated Person......  Establishment..........  Annual.
53..................................             8.7          519.18  Designated Person......  Establishment..........  Annual.
54..................................             8.7          829.10  Designated Person......  Establishment..........  Annual.
55..................................             8.7          854.67  Designated Person......  Establishment..........  Annual.
56..................................             8.7          485.04  Designated Person......  Establishment..........  Annual.
61..................................             8.7          515.54  Designated Person......  Establishment..........  Annual.
62..................................             8.7          484.68  Designated Person......  Establishment..........  Annual.
71..................................             8.7          405.16  Designated Person......  Establishment..........  Annual.
72..................................             8.7          288.08  Designated Person......  Establishment..........  Annual.
81..................................             8.7          471.94  Designated Person......  Establishment..........  Annual.
92..................................             8.7          633.56  Designated Person......  Establishment..........  Annual.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                    Indoor Identification of Heat-Exposed Work Areas
--------------------------------------------------------------------------------------------------------------------------------------------------------
11..................................             3.0          149.49  Designated Person......  Establishment..........  Every 5 Years.
21..................................             3.0          246.94  Designated Person......  Establishment..........  Every 5 Years.
22..................................             3.0          281.83  Designated Person......  Establishment..........  Every 5 Years.
23..................................             3.0          205.58  Designated Person......  Establishment..........  Every 5 Years.
31-33...............................             3.0          209.91  Designated Person......  Establishment..........  Every 5 Years.
42..................................             3.0          206.32  Designated Person......  Establishment..........  Every 5 Years.
44-45...............................             3.0          128.67  Designated Person......  Establishment..........  Every 5 Years.
48-49...............................             3.0          181.77  Designated Person......  Establishment..........  Every 5 Years.
51..................................             3.0          266.33  Designated Person......  Establishment..........  Every 5 Years.
52..................................             3.0          242.93  Designated Person......  Establishment..........  Every 5 Years.
53..................................             3.0          179.72  Designated Person......  Establishment..........  Every 5 Years.
54..................................             3.0          287.00  Designated Person......  Establishment..........  Every 5 Years.
55..................................             3.0          295.85  Designated Person......  Establishment..........  Every 5 Years.
56..................................             3.0          167.90  Designated Person......  Establishment..........  Every 5 Years.
61..................................             3.0          178.46  Designated Person......  Establishment..........  Every 5 Years.
62..................................             3.0          167.77  Designated Person......  Establishment..........  Every 5 Years.
71..................................             3.0          140.25  Designated Person......  Establishment..........  Every 5 Years.
72..................................             3.0           99.72  Designated Person......  Establishment..........  Every 5 Years.
81..................................             3.0          163.36  Designated Person......  Establishment..........  Every 5 Years.
92..................................             3.0          219.31  Designated Person......  Establishment..........  Every 5 Years.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                             Work Area Evaluation--Employee
--------------------------------------------------------------------------------------------------------------------------------------------------------
11..................................            0.25            6.70  At-Risk Worker.........  Establishment..........  Every 5 Years.
21..................................            0.25           11.61  At-Risk Worker.........  Establishment..........  Every 5 Years.
22..................................            0.25           18.88  At-Risk Worker.........  Establishment..........  Every 5 Years.
23..................................            0.25           10.99  At-Risk Worker.........  Establishment..........  Every 5 Years.
31-33...............................            0.25            9.17  At-Risk Worker.........  Establishment..........  Every 5 Years.
42..................................            0.25           10.58  At-Risk Worker.........  Establishment..........  Every 5 Years.
44-45...............................            0.25            6.57  At-Risk Worker.........  Establishment..........  Every 5 Years.
48-49...............................            0.25            8.32  At-Risk Worker.........  Establishment..........  Every 5 Years.
51..................................            0.25           14.38  At-Risk Worker.........  Establishment..........  Every 5 Years.
52..................................            0.25           14.56  At-Risk Worker.........  Establishment..........  Every 5 Years.
53..................................            0.25            9.36  At-Risk Worker.........  Establishment..........  Every 5 Years.
54..................................            0.25           19.08  At-Risk Worker.........  Establishment..........  Every 5 Years.
55..................................            0.25           22.01  At-Risk Worker.........  Establishment..........  Every 5 Years.
56..................................            0.25            6.89  At-Risk Worker.........  Establishment..........  Every 5 Years.
61..................................            0.25            8.17  At-Risk Worker.........  Establishment..........  Every 5 Years.
62..................................            0.25            7.12  At-Risk Worker.........  Establishment..........  Every 5 Years.
71..................................            0.25            6.30  At-Risk Worker.........  Establishment..........  Every 5 Years.
72..................................            0.25            6.03  At-Risk Worker.........  Establishment..........  Every 5 Years.
81..................................            0.25            8.58  At-Risk Worker.........  Establishment..........  Every 5 Years.
92..................................            0.25           12.68  At-Risk Worker.........  Establishment..........  Every 5 Years.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                     Review Monitoring Equipment User Manual--Indoor
--------------------------------------------------------------------------------------------------------------------------------------------------------
11..................................            0.25           12.46  Designated Person......  Establishment..........  One-Time.
21..................................            0.25           20.58  Designated Person......  Establishment..........  One-Time.
22..................................            0.25           23.49  Designated Person......  Establishment..........  One-Time.
23..................................            0.25           17.13  Designated Person......  Establishment..........  One-Time.

[[Page 70840]]

 
31-33...............................            0.25           17.49  Designated Person......  Establishment..........  One-Time.
42..................................            0.25           17.19  Designated Person......  Establishment..........  One-Time.
44-45...............................            0.25           10.72  Designated Person......  Establishment..........  One-Time.
48-49...............................            0.25           15.15  Designated Person......  Establishment..........  One-Time.
51..................................            0.25           22.19  Designated Person......  Establishment..........  One-Time.
52..................................            0.25           20.24  Designated Person......  Establishment..........  One-Time.
53..................................            0.25           14.98  Designated Person......  Establishment..........  One-Time.
54..................................            0.25           23.92  Designated Person......  Establishment..........  One-Time.
55..................................            0.25           24.65  Designated Person......  Establishment..........  One-Time.
56..................................            0.25           13.99  Designated Person......  Establishment..........  One-Time.
61..................................            0.25           14.87  Designated Person......  Establishment..........  One-Time.
62..................................            0.25           13.98  Designated Person......  Establishment..........  One-Time.
71..................................            0.25           11.69  Designated Person......  Establishment..........  One-Time.
72..................................            0.25            8.31  Designated Person......  Establishment..........  One-Time.
81..................................            0.25           13.61  Designated Person......  Establishment..........  One-Time.
92..................................            0.25           18.28  Designated Person......  Establishment..........  One-Time.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source: OSHA estimate derived from BLS, 2023c; BLS, 2024b; O*NET, 2023; EPA, 2002; and Rice, 2002.


                                          Table VIII.C.11--Equipment-Based Unit Costs--Identifying Heat Hazards
                                                                         [2023$]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                           Total cost per
                   Item                         Units         Unit cost         unit                   Basis                        Frequency
--------------------------------------------------------------------------------------------------------------------------------------------------------
Monitoring Equipment--Indoor.............             1.0           99.00           99.00  Establishment...............  One-Time.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source: Kestrel Instruments, 2024.

    D. Requirements at or Above the Initial Heat Trigger
    When employees are exposed to heat at or above the initial heat 
trigger, the proposed standard includes provisions related to drinking 
water, break areas, work area controls, acclimatization, rest breaks, 
and effective communication. The costs associated with the evaluation 
of fan use in paragraph I(6) are included as part of the planning and 
hazard evaluation discussed in section VIII.C.IV.C. OSHA has not 
included costs related to cooling PPE as included in proposed paragraph 
I(e)(10). Based on feedback from Small Entity Representatives who spoke 
on the topic during the SBAR Panel process, OSHA believes that use of 
cooling PPE is not widespread. Where employers are requiring or 
permitting the use of cooling PPE, OSHA expects that these employers 
will train employees to remove the PPE once it loses its cooling 
properties and will include this requirement in their HIIPPs. The cost 
for this would be included in the costs associated with proposed 
paragraphs (c) and (h).
I. Drinking Water
    Employers would be required to provide access to one quart (32 
fluid ounces) of suitably cool drinking water per employee per hour for 
the entire shift. To comply with this requirement at both outdoor and 
indoor work sites, OSHA assumes employers would purchase 40-quart water 
coolers (with spigots) sufficient to provide the required amount of 
water. For this analysis, OSHA estimates that the cost of one 40-quart 
cooler is incurred for every 40 employees. Employers are assumed to 
purchase one reusable water bottle per employee. Because existing OSHA 
standards already require employers to provide drinking water, OSHA 
assumes that nearly all employers currently provide water to their 
employees. The costs incurred to comply with this proposed standard are 
assumed to be a result of employers not providing the quantity of water 
specified by the proposed standard.
II. Break Area(s) at Outdoor Work Sites
    For outdoor work sites, OSHA would require employers to provide 
employees working outdoors with a break area. Break areas must be 
readily accessible to the work area and able to accommodate the number 
of employees on break. Additionally, break areas must have artificial 
or natural shade, or be an air-conditioned space (e.g., trailers, 
vehicles, structures). OSHA assumes that employers without existing 
break areas will use artificial shade in the form of a 12x12 foot tent 
that all employees on break can reasonably access.
III. Break Area(s) and Work Area(s) at Indoor Work Sites
    OSHA would require employers with indoor work sites to provide 
employees at those sites with a break area. These break areas must be 
readily accessible to the work area and able to accommodate the number 
of employees on break. This space must be air-conditioned or have 
increased air movement and, if appropriate, de-humidification. OSHA 
assumes that employers without existing air-conditioned breakrooms will 
designate a room or an area large enough to accommodate employees on 
break and that these areas will contain adequate fans and 
dehumidifiers. Further, employers would be required to provide measures 
that reduce employee exposure to heat in the work area. One of the ways 
employers can comply with this requirement is by providing increased 
air movement and, if appropriate, de-humidification. Adequate fans and 
dehumidifiers could be used to comply with this requirement. Overall, 
OSHA assumes that, in all States and territories in the U.S., the 
average employer that does not already have air conditioning, fans, or 
dehumidifiers in place will provide two fans per ten employees and, in 
States where humid conditions may occur, the average employer would 
also provide two dehumidifiers per ten employees.

[[Page 70841]]

IV. Acclimatization
    The proposed standard would require employers to adopt protections 
for new and returning employees who may not be acclimatized to working 
in the heat at or above the initial heat trigger during their first 
week on the job or their first week back on the job after an employee 
is away from work for more than 14 days. For new employees, OSHA 
assumes that employers would implement a plan that incorporates the 
measures required in paragraph (f) when the initial heat trigger is met 
or exceeded during the first week of work. For purposes of estimating 
the cost of compliance with this provision, OSHA calculated the cost of 
rest breaks and observation for signs and symptoms during an employee's 
first week. While paragraph (f) also requires a hazard alert, OSHA 
assumes that the hazard alert can be provided by the designated person 
while conducting observation or during training (for new employees).
    The cost of rest breaks and observation during the first week of 
work, assuming 8-hour shifts that coincide with heat index measurements 
that meet or exceed the initial heat trigger but do not meet the high 
heat trigger, equates to roughly 41.75 minutes per day for every new 
indoor employee and 47.75 minutes per day for every new outdoor 
employee during the employee's first week on the job. These estimates 
are the same for returning employees during their first week after 
returning to work when the heat index is at or above the initial heat 
trigger. No additional costs were estimated for new or returning 
employees when the temperature meets or exceeds the high heat trigger, 
as employers are already required to follow the high heat procedures.
    OSHA did not make an additional adjustment for cost savings (see 
Appendix A at the end of this section for a description of cost savings 
methodology) as the conditions of those additional rest breaks are 
different (i.e., different temperature range-rest break combination) 
than those at which the estimates of labor productivity loss due to 
pacing in the heat were calculated. To the extent that pacing is 
reduced for employees undergoing acclimatization protocols, this could 
overstate the costs of acclimatization. OSHA welcomes comment on this 
issue and whether the agency should extend the potential cost savings 
from reduced pacing to workers during their acclimatization period.
V. Rest Breaks if Needed
    The proposed standard would require that employers allow and 
encourage their employees to take paid rest breaks if needed once the 
initial heat trigger is met or exceeded to prevent overheating. OSHA 
assumes that, per 8-hour shift, at-risk employees will take one 10-
minute if-needed rest break.\62\ OSHA estimates, on average, an 
additional two minutes for indoor employees per break and an additional 
four minutes for outdoor employees per break to account for the time to 
walk to and from the break area.\63\ OSHA welcomes feedback on the 
assumption that an average employee will take one ten-minute if-needed 
rest break when the temperature is at or above the initial heat trigger 
and the assumptions for travel time to and from the break area for 
indoor and outdoor settings.
---------------------------------------------------------------------------

    \62\ If-needed rest breaks by new and returning employees when 
the temperature meets or exceeds the initial heat trigger and is 
below the high heat trigger are accounted for in the acclimatization 
costs (section VIII.C.IV.D.IV). To avoid double counting, if-needed 
rest breaks were not costed for these employees during their first 
week of work (for new hires) or the first week back from leave (for 
returning workers).
    \63\ These estimates of time needed to walk to and from the 
break area are meant to be averages across all workers in all 
settings. In some large indoor settings like warehouses or large 
manufacturing facilities, the break area may be further from the 
work areas than other indoor settings where the break area may be 
directly adjacent to work areas. In outdoor settings, OSHA expects 
the employer will use a mobile break area set up that allows the 
break area to be relocated as close as possible to the location 
employees are working on a given day. However, OSHA recognizes that 
it may not always be possible to have a break area immediately 
adjacent to all outdoor work area(s) and some outdoor work sites may 
have workers spread over relatively large areas (e.g., some 
agricultural settings, large-scale infrastructure construction 
projects), which could result in slightly longer times needed to 
walk to and from the break area.
---------------------------------------------------------------------------

    OSHA has preliminarily determined that when employees are offered 
rest breaks, cost savings will accrue to employers currently 
noncompliant with the rest break requirements, as their employees will 
work more efficiently during the work time not spent on rest breaks 
(i.e., pace less). At the initial heat trigger, some of the estimated 
unit cost for if-needed rest breaks (i.e., 10 minutes plus travel time) 
will be offset by this reduction in pacing, which OSHA considers as 
cost savings for employers.
    For the purposes of calculating accrued employer cost savings, OSHA 
defined three groups of employees with varying existing break levels 
(see the introduction in appendix A at the end of this section for 
detailed definitions of each group). Group 1 corresponds to employees 
at establishments that do not currently provide rest breaks when the 
initial heat trigger is met or exceeded. Group 2 corresponds to 
employees at establishments that do provide if-needed rest breaks when 
the initial heat trigger is met or exceeded, but do not have required 
rest breaks for when the high heat trigger is met or exceeded. Group 3 
captures employees at establishments that have already implemented rest 
breaks protocols that meet the rest break requirements outlined in this 
proposed standard.\64\
---------------------------------------------------------------------------

    \64\ OSHA estimates that approximately 6.1% of employees are in 
Group 1, 46.9% are in Group 2, and the remaining 47.0% are in Group 
3.
---------------------------------------------------------------------------

    As mentioned in section VIII.C.II.B. and detailed further in 
appendix A at the end of this section, OSHA estimated the minutes spent 
pacing for each of the three groups when they are working at or above 
the initial heat trigger. Table VIII.C.12. below shows the time 
(minutes) per 8-hour shift that OSHA estimates employees in each group 
currently spend pacing when the initial heat trigger is met or 
exceeded. Using these estimates, OSHA assumes that with the 
implementation of if-needed rest breaks, all employees in Group 1 
(i.e., not currently taking any breaks) will behave like Group 2 (i.e., 
those currently taking if-needed rest breaks at or above the initial 
heat trigger but not scheduled rest breaks at or above the high heat 
trigger), reducing their pacing (working more efficiently) by 14.0 - 
11.2 = 2.8 minutes per shift at the initial heat trigger.
    For outdoor employees, this reduction in pacing translates into 
accrued cost savings of 20 percent (2.8 minutes of pacing reduced/14 
minutes of if-needed rest break time \65\) of the unit time-cost per 
break. This effectively reduces the unit cost of if-needed rest breaks 
for outdoor employees from 14 to 11.2 minutes. Similarly, for indoor 
employees, this reduction in pacing reduces the unit time-cost by 2.8/
12 = 23.33 percent, from 12 \66\ to 9.2 minutes per 8-hour shift.
---------------------------------------------------------------------------

    \65\ 10 minutes of if-needed rest break time and 4 minutes of 
travel time.
    \66\ 10 minutes of if-needed rest break time and 2 minutes of 
travel time.

[[Page 70842]]



 Table VIII.C.12--Labor Productivity Loss from Pacing Above Initial Heat Trigger Before and After Implementation
             of Required if Needed Rest Breaks and Labor Cost Savings per 8-Hour Shift per Employee
----------------------------------------------------------------------------------------------------------------
                                                       Labor productivity    Labor productivity
                                                        loss from pacing      loss from pacing       Estimated
                                                         before required       after required       labor cost
           Group                Group description     initial heat trigger  initial heat trigger      savings
                                                           rest breaks           rest breaks         (minutes)
                                                            (minutes)             (minutes)
----------------------------------------------------------------------------------------------------------------
Group 1...................  Employees at                              14.0                  11.2             2.8
                             establishments that do
                             not currently provide
                             any rest breaks.
Group 2...................  Employees at                              11.2                  11.2             0.0
                             establishments that
                             provide rest breaks
                             that meet the initial
                             heat trigger rest break
                             requirements, but not
                             the high heat trigger
                             rest break requirements.
Group 3...................  Employees at                               0.0                   0.0             0.0
                             establishments that
                             provide rest breaks
                             that meet the initial
                             and high heat trigger
                             rest break requirements.
----------------------------------------------------------------------------------------------------------------
Source: OSHA estimate.
Note: OSHA estimates that approximately 6.1 percent of employees are in Group 1, 46.9 percent are in Group 2,
  and 47.0 percent are in Group 3.

VI. Effective Communication
    Employers would be required to maintain a means of effective two-
way communication with employees whenever the initial heat trigger is 
met or exceeded. OSHA assumes that a designated person would 
communicate with each employee three times for every 8-hour shift that 
meets or exceeds the initial heat trigger and would spend 15 seconds on 
each communication. At-risk workers are assumed to spend the same 
amount of time in communication with the designated person. It is 
assumed that all employers and employees have a current method for 
effective two-way communication (e.g., cell phones, walkie talkies) 
that may be currently used to communicate information about work-
related concerns and that these methods may be used when the initial 
heat trigger is met or exceeded. OSHA welcomes comments on existing 
methods of two-way communication between employees and employers.
    Table VIII.C.13. shows the unit costs for the requirements at or 
above the initial heat trigger by industry sector. The rest break unit 
costs reported in table VIII.C.13. do not reflect the cost savings 
offset discussed above. Table VIII.C.14. shows the equipment costs 
(water coolers, water bottles, pedestal fans, dehumidifiers, and tents 
for artificial shade) that employers would incur to comply with the 
requirements when the initial heat trigger is met or exceeded.

                               Table VIII.C.13--Labor-Based Unit Costs--Requirements at or Above the Initial Heat Trigger
                                                                         [2023$]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                Sector                      Hours         Unit cost         Labor category                 Basis                     Frequency
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                     New Employee Acclimatization--Designated Person
--------------------------------------------------------------------------------------------------------------------------------------------------------
11...................................            0.01           $0.62  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
21...................................            0.01            1.03  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
22...................................            0.01            1.17  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
23...................................            0.01            0.86  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
31-33................................            0.01            0.87  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
42...................................            0.01            0.86  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
44-45................................            0.01            0.54  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
48-49................................            0.01            0.76  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
51...................................            0.01            1.11  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
52...................................            0.01            1.01  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
53...................................            0.01            0.75  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
54...................................            0.01            1.20  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
55...................................            0.01            1.23  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
56...................................            0.01            0.70  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
61...................................            0.01            0.74  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
62...................................            0.01            0.70  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
71...................................            0.01            0.58  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
72...................................            0.01            0.42  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
81...................................            0.01            0.68  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
92...................................            0.01            0.91  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                  Returning Employee Acclimatization--Designated Person
--------------------------------------------------------------------------------------------------------------------------------------------------------
11...................................            0.01            0.62  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
21...................................            0.01            1.03  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
22...................................            0.01            1.17  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
23...................................            0.01            0.86  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
31-33................................            0.01            0.87  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
42...................................            0.01            0.86  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).

[[Page 70843]]

 
44-45................................            0.01            0.54  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
48-49................................            0.01            0.76  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
51...................................            0.01            1.11  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
52...................................            0.01            1.01  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
53...................................            0.01            0.75  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
54...................................            0.01            1.20  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
55...................................            0.01            1.23  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
56...................................            0.01            0.70  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
61...................................            0.01            0.74  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
62...................................            0.01            0.70  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
71...................................            0.01            0.58  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
72...................................            0.01            0.42  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
81...................................            0.01            0.68  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
92...................................            0.01            0.91  Designated Person.......  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                           New Indoor Employee Acclimatization
--------------------------------------------------------------------------------------------------------------------------------------------------------
11...................................             0.7           18.65  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
21...................................             0.7           32.33  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
22...................................             0.7           52.56  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
23...................................             0.7           30.58  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
31-33................................             0.7           25.52  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
42...................................             0.7           29.46  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
44-45................................             0.7           18.29  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
48-49................................             0.7           23.15  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
51...................................             0.7           40.04  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
52...................................             0.7           40.53  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
53...................................             0.7           26.05  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
54...................................             0.7           53.12  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
55...................................             0.7           61.25  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
56...................................             0.7           19.18  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
61...................................             0.7           22.74  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
62...................................             0.7           19.82  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
71...................................             0.7           17.54  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
72...................................             0.7           16.79  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
81...................................             0.7           23.88  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
92...................................             0.7           35.30  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                          New Outdoor Employee Acclimatization
--------------------------------------------------------------------------------------------------------------------------------------------------------
11...................................             0.8           21.33  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
21...................................             0.8           36.97  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
22...................................             0.8           60.11  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
23...................................             0.8           34.97  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
31-33................................             0.8           29.19  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
42...................................             0.8           33.69  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
44-45................................             0.8           20.92  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
48-49................................             0.8           26.48  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
51...................................             0.8           45.79  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
52...................................             0.8           46.35  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
53...................................             0.8           29.80  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
54...................................             0.8           60.75  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
55...................................             0.8           70.05  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
56...................................             0.8           21.94  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
61...................................             0.8           26.01  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
62...................................             0.8           22.66  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
71...................................             0.8           20.06  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
72...................................             0.8           19.20  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
81...................................             0.8           27.32  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
92...................................             0.8           40.37  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                        Returning Indoor Employee Acclimatization
--------------------------------------------------------------------------------------------------------------------------------------------------------
11...................................             0.7           18.65  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
21...................................             0.7           32.33  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
22...................................             0.7           52.56  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
23...................................             0.7           30.58  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
31-33................................             0.7           25.52  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
42...................................             0.7           29.46  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
44-45................................             0.7           18.29  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
48-49................................             0.7           23.15  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).

[[Page 70844]]

 
51...................................             0.7           40.04  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
52...................................             0.7           40.53  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
53...................................             0.7           26.05  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
54...................................             0.7           53.12  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
55...................................             0.7           61.25  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
56...................................             0.7           19.18  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
61...................................             0.7           22.74  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
62...................................             0.7           19.82  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
71...................................             0.7           17.54  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
72...................................             0.7           16.79  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
81...................................             0.7           23.88  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
92...................................             0.7           35.30  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                       Returning Outdoor Employee Acclimatization
--------------------------------------------------------------------------------------------------------------------------------------------------------
11...................................             0.8           21.33  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
21...................................             0.8           36.97  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
22...................................             0.8           60.11  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
23...................................             0.8           34.97  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
31-33................................             0.8           29.19  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
42...................................             0.8           33.69  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
44-45................................             0.8           20.92  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
48-49................................             0.8           26.48  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
51...................................             0.8           45.79  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
52...................................             0.8           46.35  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
53...................................             0.8           29.80  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
54...................................             0.8           60.75  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
55...................................             0.8           70.05  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
56...................................             0.8           21.94  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
61...................................             0.8           26.01  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
62...................................             0.8           22.66  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
71...................................             0.8           20.06  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
72...................................             0.8           19.20  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
81...................................             0.8           27.32  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
92...................................             0.8           40.37  At-Risk Worker..........  Employee................  Daily at Initial Heat Trigger
                                                                                                                            (Up to 5 Days).
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                       Rest Breaks at Initial Heat Trigger--Indoor
--------------------------------------------------------------------------------------------------------------------------------------------------------
11...................................            0.20            5.36  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
21...................................            0.20            9.29  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
22...................................            0.20           15.11  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
23...................................            0.20            8.79  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
31-33................................            0.20            7.34  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
42...................................            0.20            8.47  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
44-45................................            0.20            5.26  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
48-49................................            0.20            6.65  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
51...................................            0.20           11.51  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
52...................................            0.20           11.65  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
53...................................            0.20            7.49  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
54...................................            0.20           15.27  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
55...................................            0.20           17.60  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
56...................................            0.20            5.51  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
61...................................            0.20            6.54  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
62...................................            0.20            5.70  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
71...................................            0.20            5.04  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
72...................................            0.20            4.83  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
81...................................            0.20            6.87  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
92...................................            0.20           10.14  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                      Rest Breaks at Initial Heat Trigger--Outdoor
--------------------------------------------------------------------------------------------------------------------------------------------------------
11...................................            0.23            6.25  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
21...................................            0.23           10.84  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
22...................................            0.23           17.62  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
23...................................            0.23           10.25  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
31-33................................            0.23            8.56  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
42...................................            0.23            9.88  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
44-45................................            0.23            6.13  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
48-49................................            0.23            7.76  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
51...................................            0.23           13.43  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
52...................................            0.23           13.59  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.

[[Page 70845]]

 
53...................................            0.23            8.74  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
54...................................            0.23           17.81  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
55...................................            0.23           20.54  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
56...................................            0.23            6.43  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
61...................................            0.23            7.63  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
62...................................            0.23            6.65  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
71...................................            0.23            5.88  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
72...................................            0.23            5.63  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
81...................................            0.23            8.01  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
92...................................            0.23           11.84  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                           Effective Communication--Supervisor
--------------------------------------------------------------------------------------------------------------------------------------------------------
11...................................            0.01            0.62  Designated Person.......  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
21...................................            0.01            1.03  Designated Person.......  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
22...................................            0.01            1.17  Designated Person.......  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
23...................................            0.01            0.86  Designated Person.......  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
31-33................................            0.01            0.87  Designated Person.......  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
42...................................            0.01            0.86  Designated Person.......  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
44-45................................            0.01            0.54  Designated Person.......  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
48-49................................            0.01            0.76  Designated Person.......  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
51...................................            0.01            1.11  Designated Person.......  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
52...................................            0.01            1.01  Designated Person.......  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
53...................................            0.01            0.75  Designated Person.......  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
54...................................            0.01            1.20  Designated Person.......  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
55...................................            0.01            1.23  Designated Person.......  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
56...................................            0.01            0.70  Designated Person.......  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
61...................................            0.01            0.74  Designated Person.......  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
62...................................            0.01            0.70  Designated Person.......  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
71...................................            0.01            0.58  Designated Person.......  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
72...................................            0.01            0.42  Designated Person.......  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
81...................................            0.01            0.68  Designated Person.......  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
92...................................            0.01            0.91  Designated Person.......  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                            Effective Communication--Employee
--------------------------------------------------------------------------------------------------------------------------------------------------------
11...................................            0.01            0.33  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
21...................................            0.01            0.58  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
22...................................            0.01            0.94  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
23...................................            0.01            0.55  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
31-33................................            0.01            0.46  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
42...................................            0.01            0.53  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
44-45................................            0.01            0.33  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
48-49................................            0.01            0.42  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
51...................................            0.01            0.72  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
52...................................            0.01            0.73  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
53...................................            0.01            0.47  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
54...................................            0.01            0.95  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
55...................................            0.01            1.10  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
56...................................            0.01            0.34  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
61...................................            0.01            0.41  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
62...................................            0.01            0.36  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
71...................................            0.01            0.32  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
72...................................            0.01            0.30  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
81...................................            0.01            0.43  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
92...................................            0.01            0.63  At-Risk Worker..........  Employee................  Daily at Initial Heat
                                                                                                                            Trigger.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source: OSHA estimate derived from BLS, 2023c; BLS, 2024b; O*NET, 2023; EPA, 2002; and Rice, 2002.


                             Table VIII.C.14--Equipment-Based Unit Costs--Requirements at or Above the Initial Heat Trigger
                                                                         [2023]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                           Total cost per
                   Item                         Units         Unit cost         unit                   Basis                        Frequency
--------------------------------------------------------------------------------------------------------------------------------------------------------
Coolers with Spigot......................             1.0          $79.99          $79.99  Employee....................  One-Time.
Reusable Water Bottle....................             1.0            0.59            0.59  Employee....................  One-Time.
Outdoor Break Area Engineering Control...             1.0          119.99          119.99  Establishment...............  One-Time.
Air Movement.............................             2.0          134.99          269.98  Employee....................  One-Time.

[[Page 70846]]

 
Humidity Control.........................             2.0           39.19           78.38  Employee....................  One-Time.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source: OSHA estimate based on Igloo Products Corp., 2024; DiscountMugs, 2024; Amazon.com, Inc, 2024a; Amazon.com, Inc., 2024b; and WebstaurantStore,
  2024.

E. Requirements At or Above the High Heat Trigger
    When the high heat trigger is met or exceeded, this proposed 
standard includes provisions related to rest breaks, observation of 
employees for signs and symptoms of heat illness, hazard alerts, and 
excessively high heat areas.
I. Rest Breaks
    When the high heat trigger is met or exceeded, employers would be 
required to provide a minimum of 15-minute paid rest breaks at least 
every two hours. The proposed standard specifies that a meal break may 
count as a rest break, even if it is not otherwise required by law to 
be paid. For this analysis, OSHA assumes two paid 15-minute rest breaks 
and an unpaid meal break per at-risk worker per 8-hour shift where the 
high heat trigger is met or exceeded. At the high heat trigger, 
employers must also provide if-needed rest breaks (as part of the 
requirements of the initial heat trigger). Therefore, OSHA assumes that 
when the high heat trigger is met or exceeded, in addition to 30 
minutes per 8-hour shift of scheduled rest break time, at-risk workers 
would take a five-minute if-needed rest break. The travel time to walk 
to and from the break area is also accounted for and OSHA assumes two 
minutes for indoor employees and four minutes for outdoor employees per 
rest break.
    Similar to the discussion in section VIII.C.IV.D.V., OSHA estimated 
the amount of time that employees spend pacing themselves when the high 
heat trigger is met or exceeded over an 8-hour shift (see table 
VIII.C.15.). These estimates reflect three groups of employees based on 
their respective establishments' estimated compliance with the rest 
break requirements outlined in this proposed standard. Group 1 
corresponds to employees at establishments that do not currently 
provide rest breaks that meet the requirements when the initial heat 
trigger is met. Group 2 corresponds to employees at establishments that 
do provide if-needed rest breaks when the initial heat trigger is met 
or exceeded, but do not have required rest breaks for when the high 
heat trigger is met or exceeded. Group 3 captures employees at 
establishments that have already implemented rest breaks protocols that 
meet the initial and high heat trigger rest break requirements outlined 
in this proposed standard.
    Based on the estimates for pacing mentioned in section VIII.C.II.B. 
and detailed further in appendix A at the end of this section, OSHA 
estimated the reduction in pacing at the high heat trigger; the 
estimates for pacing for each group are shown in table VIII.C.15. OSHA 
estimated that with the implementation of scheduled rest breaks as well 
as if-needed rest breaks at the high heat trigger, employees in Group 1 
(i.e., that are currently noncompliant with scheduled rest breaks as 
well as if-needed rest breaks) will behave like those in Group 3 (i.e., 
rest break protocols are consistent with the requirements of the 
standard at both triggers) and therefore their pacing reduces by 40.6-
8.4 = 32.2 minutes. This reduction in pacing translates into 32.2/47 = 
68.51 percent of the unit time-cost for rest breaks of 47 minutes and 
32.2/41 = 78.53 percent out of the unit time-cost for rest breaks of 41 
minutes saved for outdoor and indoor employees, respectively.
    Based on the estimates for pacing mentioned in section VIII.C.II.B. 
and detailed further in appendix A at the end of this section and 
displayed in table VIII.C.15., OSHA estimates that with the 
implementation of scheduled rest breaks at the high heat trigger, 
employees in Group 2 (i.e., that are currently noncompliant with only 
scheduled rest breaks and currently compliant with if-needed rest 
breaks) will now behave like those in Group 3 and for those employees 
pacing is reduced by 39.5-8.4 = 31.1 minutes per shift. This reduction 
in pacing (i.e., increase in worker efficiency) translates into 31.1/47 
= 66.17 percent of the unit time-cost of 47 minutes \67\ (31.1/41 = 
75.85 percent out of the unit time-cost of 41 minutes \68\) saved for 
outdoor (indoor) employees that are currently in Group 2.\69\
---------------------------------------------------------------------------

    \67\ 2 x (15-minute scheduled break + 4-minute travel time) + 1 
x (5-minute if-needed rest break + 4-minute travel time).
    \68\ 2 x (15-minute scheduled break + 2-minute travel time) + 1 
x (5-minute if-needed rest break + 2-minute travel time).
    \69\ For Group 2 as well as Group 1, for presentation purposes, 
the denominator over which unit time cost savings is translated as a 
share of the unit time cost of high heat trigger rest breaks is 
presented as 47 minutes for outdoor employees (41 minutes for indoor 
employees). The fact that employees in Group 2 are already spending 
some portion of the 47 minutes or 41 minutes in if-needed rest 
breaks is already reflected in the estimated (State-level) share of 
employees in Group 2, which is equivalent to the difference between 
the (State-level) non-compliance rate for high heat trigger rest 
breaks (scheduled as well as if-needed rest breaks) and the (State-
level) non-compliance rate for initial heat trigger rest breaks (if-
needed rest breaks). Most of the employees in Group 2 (approximately 
74 percent) are estimated to be already taking if-needed rest breaks 
but not scheduled breaks. The rest of the employees in Group 2 are, 
in addition to if-needed rest breaks, also already taking partial 
scheduled breaks that fall short of (i.e., are not fully compliant 
with) the scheduled breaks that are required in the proposed 
standard. The purpose of such classification of employees already 
taking partial scheduled breaks as part of Group 2 (employees at 
establishments that do not have required rest breaks for when the 
high heat trigger is met or exceeded) is to avoid overcomplicating 
the computation and presentation of the cost savings. Such 
classification may potentially result in the overestimation of cost 
savings from the high heat trigger rest breaks. However, as 
mentioned throughout this section, there are also reasons why the 
cost savings are also potentially underestimated (e.g., due to 
temperature data limitations as mentioned in section VIII.C.II.B.).

[[Page 70847]]



 Table VIII.C.15--Labor Productivity Loss From Spent Pacing at High Heat Trigger Before and After Implementation
                  of Required If-Needed and Scheduled Rest Breaks per 8-Hour Shift per Employee
----------------------------------------------------------------------------------------------------------------
                                                       Labor productivity    Labor productivity
                                                       loss from pacing at    loss from pacing       Estimated
           Group                Group description     before required high   after required high    labor cost
                                                        heat trigger rest     heat trigger rest       savings
                                                        breaks (minutes)      breaks (minutes)       (minutes)
----------------------------------------------------------------------------------------------------------------
Group 1...................  Employees at                              40.6                   8.4            32.2
                             establishments that do
                             not currently provide
                             any rest breaks.
Group 2...................  Employees at                              39.5                   8.4            31.1
                             establishments that
                             provide rest breaks
                             that meet the initial
                             heat trigger rest break
                             requirements.
Group 3...................  Employees at                               8.4                   8.4             0.0
                             establishments that
                             provide rest breaks
                             that meet the initial
                             and high heat trigger
                             rest break requirements.
----------------------------------------------------------------------------------------------------------------
Source: OSHA estimate.
Note: OSHA estimates that approximately 6.1 percent of employees are in Group 1, 46.9 percent are in Group 2,
  and 47.0 percent are in Group 3.

II. Observation for Signs and Symptoms
    Employers would be required to observe employees for signs and 
symptoms of heat-related illness at or above the high heat trigger. The 
proposed standard provides options for complying with this requirement, 
including a mandatory buddy system and observation of employees by a 
supervisor or heat safety coordinator. Additionally, the proposed 
standard has a provision for communication with employees who are lone 
workers every 2 hours. OSHA assumes that all employers will use 
supervisors \70\ to conduct observation of employees \71\ (with one 
supervisor or heat safety coordinator responsible for observing no more 
than 20 employees). OSHA estimates this option would require 15 seconds 
of the designated person's time three times per employee for every
---------------------------------------------------------------------------

    \70\ For this analysis, OSHA uses the wages developed for 
designated persons to represent supervisors' time as well.
    \71\ OSHA was unable to estimate the number of affected lone 
workers. OSHA assumes that the cost of lone workers communication 
with supervisors is the same as the cost of observation for the 
purposes of this analysis. The agency welcomes comment on this 
assumption and additional data that would allow OSHA to better 
estimate the costs for communication with lone workers.
---------------------------------------------------------------------------

    8-hour shift that meets or exceeds the high heat trigger. This 
observation requirement would also take 15 seconds of each at-risk 
worker's time three times for every 8-hour shift that meets or exceeds 
the high heat trigger.
III. Hazard Alert
    When the high heat trigger is met or exceeded, OSHA would require 
employers to notify employees of the importance of staying hydrated, 
their right to take breaks, procedures to take in a heat emergency, and 
the locations of break areas and drinking water (for mobile work 
sites). OSHA estimates that it would take five minutes one time for a 
designated person to prepare and deliver the first notification message 
to employees for the year or heat season, and that for each subsequent 
notification, the designated person will use the same format and spend 
30 seconds to update and resend the alert for each 8-hour shift at or 
above the initial heat trigger. OSHA assumes the time for at-risk 
workers to review the hazard alert is negligible and thus is not 
estimated to require any time.
IV. Warning Signs for Excessively High Heat Areas
    For indoor workplaces, employers would be required to place warning 
signs at areas with ambient temperatures that regularly exceed 120 
[deg]F. OSHA assumes that this requirement imposes costs only to 
certain industries that are likely to have radiant heat sources (e.g., 
furnaces, hot water systems, ovens, smelting processes). OSHA assumes 
that this control would require 1-2 warning signs for each 
establishment in industries where radiant heat sources are likely 
present (or an average of 1.5 signs per establishment). OSHA estimates 
it would take a designated person 5 minutes to install each sign.
    Table VIII.C.16. shows the unit costs for the requirements under 
the high heat trigger conditions by industry sector. The rest break 
unit costs reported in table VIII.C.16. do not reflect the cost savings 
offset discussed above. Table VIII.C.17. shows the equipment costs that 
employers would incur in order to comply with the requirements when the 
high heat trigger is met or exceeded.

             Table VIII.C.16--Labor-Based Unit Costs--Requirements at or Above the High Heat Trigger
                                                     [2023$]
----------------------------------------------------------------------------------------------------------------
            Sector                  Hours         Unit cost     Labor category       Basis          Frequency
----------------------------------------------------------------------------------------------------------------
                                    Rest Breaks at High Heat Trigger--Indoor
----------------------------------------------------------------------------------------------------------------
11...........................            0.68          $18.31  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
21...........................            0.68           31.74  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
22...........................            0.68           51.61  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
23...........................            0.68           30.03  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
31-33........................            0.68           25.07  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
42...........................            0.68           28.93  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
44-45........................            0.68           17.96  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.

[[Page 70848]]

 
48-49........................            0.68           22.74  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
51...........................            0.68           39.32  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
52...........................            0.68           39.80  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
53...........................            0.68           25.58  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
54...........................            0.68           52.16  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
55...........................            0.68           60.15  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
56...........................            0.68           18.84  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
61...........................            0.68           22.33  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
62...........................            0.68           19.46  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
71...........................            0.68           17.23  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
72...........................            0.68           16.49  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
81...........................            0.68           23.46  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
92...........................            0.68           34.66  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
----------------------------------------------------------------------------------------------------------------
                                    Rest Breaks at High Heat Trigger--Outdoor
----------------------------------------------------------------------------------------------------------------
11...........................            0.78           20.99  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
21...........................            0.78           36.39  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
22...........................            0.78           59.17  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
23...........................            0.78           34.43  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
31-33........................            0.78           28.73  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
42...........................            0.78           33.17  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
44-45........................            0.78           20.59  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
48-49........................            0.78           26.06  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
51...........................            0.78           45.07  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
52...........................            0.78           45.62  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
53...........................            0.78           29.33  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
54...........................            0.78           59.80  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
55...........................            0.78           68.95  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
56...........................            0.78           21.59  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
61...........................            0.78           25.60  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
62...........................            0.78           22.31  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
71...........................            0.78           19.75  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
72...........................            0.78           18.90  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
81...........................            0.78           26.89  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
92...........................            0.78           39.73  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
----------------------------------------------------------------------------------------------------------------
                              Observation for Signs and Symptoms--Designated Person
----------------------------------------------------------------------------------------------------------------
11...........................            0.01            0.62  Designated       Employee.......  Daily at High
                                                                Person.                           Heat Trigger.
21...........................            0.01            1.03  Designated       Employee.......  Daily at High
                                                                Person.                           Heat Trigger.
22...........................            0.01            1.17  Designated       Employee.......  Daily at High
                                                                Person.                           Heat Trigger.
23...........................            0.01            0.86  Designated       Employee.......  Daily at High
                                                                Person.                           Heat Trigger.
31-33........................            0.01            0.87  Designated       Employee.......  Daily at High
                                                                Person.                           Heat Trigger.
42...........................            0.01            0.86  Designated       Employee.......  Daily at High
                                                                Person.                           Heat Trigger.
44-45........................            0.01            0.54  Designated       Employee.......  Daily at High
                                                                Person.                           Heat Trigger.
48-49........................            0.01            0.76  Designated       Employee.......  Daily at High
                                                                Person.                           Heat Trigger.
51...........................            0.01            1.11  Designated       Employee.......  Daily at High
                                                                Person.                           Heat Trigger.
52...........................            0.01            1.01  Designated       Employee.......  Daily at High
                                                                Person.                           Heat Trigger.
53...........................            0.01            0.75  Designated       Employee.......  Daily at High
                                                                Person.                           Heat Trigger.
54...........................            0.01            1.20  Designated       Employee.......  Daily at High
                                                                Person.                           Heat Trigger.
55...........................            0.01            1.23  Designated       Employee.......  Daily at High
                                                                Person.                           Heat Trigger.
56...........................            0.01            0.70  Designated       Employee.......  Daily at High
                                                                Person.                           Heat Trigger.
61...........................            0.01            0.74  Designated       Employee.......  Daily at High
                                                                Person.                           Heat Trigger.
62...........................            0.01            0.70  Designated       Employee.......  Daily at High
                                                                Person.                           Heat Trigger.
71...........................            0.01            0.58  Designated       Employee.......  Daily at High
                                                                Person.                           Heat Trigger.
72...........................            0.01            0.42  Designated       Employee.......  Daily at High
                                                                Person.                           Heat Trigger.
81...........................            0.01            0.68  Designated       Employee.......  Daily at High
                                                                Person.                           Heat Trigger.
92...........................            0.01            0.91  Designated       Employee.......  Daily at High
                                                                Person.                           Heat Trigger.
----------------------------------------------------------------------------------------------------------------
                               Observation for Signs and Symptoms--At-Risk Worker
----------------------------------------------------------------------------------------------------------------
11...........................            0.01            0.33  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
21...........................            0.01            0.58  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
22...........................            0.01            0.94  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
23...........................            0.01            0.55  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
31-33........................            0.01            0.46  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
42...........................            0.01            0.53  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
44-45........................            0.01            0.33  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
48-49........................            0.01            0.42  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
51...........................            0.01            0.72  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.

[[Page 70849]]

 
52...........................            0.01            0.73  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
53...........................            0.01            0.47  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
54...........................            0.01            0.95  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
55...........................            0.01            1.10  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
56...........................            0.01            0.34  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
61...........................            0.01            0.41  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
62...........................            0.01            0.36  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
71...........................            0.01            0.32  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
72...........................            0.01            0.30  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
81...........................            0.01            0.43  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
92...........................            0.01            0.63  At-Risk Worker.  Employee.......  Daily at High
                                                                                                  Heat Trigger.
----------------------------------------------------------------------------------------------------------------
                                        Initial Hazard Alert--Supervisor
----------------------------------------------------------------------------------------------------------------
11...........................            0.08            4.15  Designated       Establishment..  Annual.
                                                                Person.
21...........................            0.08            6.86  Designated       Establishment..  Annual.
                                                                Person.
22...........................            0.08            7.83  Designated       Establishment..  Annual.
                                                                Person.
23...........................            0.08            5.71  Designated       Establishment..  Annual.
                                                                Person.
31-33........................            0.08            5.83  Designated       Establishment..  Annual.
                                                                Person.
42...........................            0.08            5.73  Designated       Establishment..  Annual.
                                                                Person.
44-45........................            0.08            3.57  Designated       Establishment..  Annual.
                                                                Person.
48-49........................            0.08            5.05  Designated       Establishment..  Annual.
                                                                Person.
51...........................            0.08            7.40  Designated       Establishment..  Annual.
                                                                Person.
52...........................            0.08            6.75  Designated       Establishment..  Annual.
                                                                Person.
53...........................            0.08            4.99  Designated       Establishment..  Annual.
                                                                Person.
54...........................            0.08            7.97  Designated       Establishment..  Annual.
                                                                Person.
55...........................            0.08            8.22  Designated       Establishment..  Annual.
                                                                Person.
56...........................            0.08            4.66  Designated       Establishment..  Annual.
                                                                Person.
61...........................            0.08            4.96  Designated       Establishment..  Annual.
                                                                Person.
62...........................            0.08            4.66  Designated       Establishment..  Annual.
                                                                Person.
71...........................            0.08            3.90  Designated       Establishment..  Annual.
                                                                Person.
72...........................            0.08            2.77  Designated       Establishment..  Annual.
                                                                Person.
81...........................            0.08            4.54  Designated       Establishment..  Annual.
                                                                Person.
92...........................            0.08            6.09  Designated       Establishment..  Annual.
                                                                Person.
----------------------------------------------------------------------------------------------------------------
                                       Subsequent Hazard Alert--Supervisor
----------------------------------------------------------------------------------------------------------------
11...........................            0.01            0.42  Designated       Establishment..  Daily at High
                                                                Person.                           Heat Trigger.
21...........................            0.01            0.69  Designated       Establishment..  Daily at High
                                                                Person.                           Heat Trigger.
22...........................            0.01            0.78  Designated       Establishment..  Daily at High
                                                                Person.                           Heat Trigger.
23...........................            0.01            0.57  Designated       Establishment..  Daily at High
                                                                Person.                           Heat Trigger.
31-33........................            0.01            0.58  Designated       Establishment..  Daily at High
                                                                Person.                           Heat Trigger.
42...........................            0.01            0.57  Designated       Establishment..  Daily at High
                                                                Person.                           Heat Trigger.
44-45........................            0.01            0.36  Designated       Establishment..  Daily at High
                                                                Person.                           Heat Trigger.
48-49........................            0.01            0.50  Designated       Establishment..  Daily at High
                                                                Person.                           Heat Trigger.
51...........................            0.01            0.74  Designated       Establishment..  Daily at High
                                                                Person.                           Heat Trigger.
52...........................            0.01            0.67  Designated       Establishment..  Daily at High
                                                                Person.                           Heat Trigger.
53...........................            0.01            0.50  Designated       Establishment..  Daily at High
                                                                Person.                           Heat Trigger.
54...........................            0.01            0.80  Designated       Establishment..  Daily at High
                                                                Person.                           Heat Trigger.
55...........................            0.01            0.82  Designated       Establishment..  Daily at High
                                                                Person.                           Heat Trigger.
56...........................            0.01            0.47  Designated       Establishment..  Daily at High
                                                                Person.                           Heat Trigger.
61...........................            0.01            0.50  Designated       Establishment..  Daily at High
                                                                Person.                           Heat Trigger.
62...........................            0.01            0.47  Designated       Establishment..  Daily at High
                                                                Person.                           Heat Trigger.
71...........................            0.01            0.39  Designated       Establishment..  Daily at High
                                                                Person.                           Heat Trigger.
72...........................            0.01            0.28  Designated       Establishment..  Daily at High
                                                                Person.                           Heat Trigger.
81...........................            0.01            0.45  Designated       Establishment..  Daily at High
                                                                Person.                           Heat Trigger.
92...........................            0.01            0.61  Designated       Establishment..  Daily at High
                                                                Person.                           Heat Trigger.
----------------------------------------------------------------------------------------------------------------
                                                Signage Placement
----------------------------------------------------------------------------------------------------------------
11...........................            0.08            4.15  Designated       Establishment..  One-Time.
                                                                Person.
21...........................            0.08            6.86  Designated       Establishment..  One-Time.
                                                                Person.
22...........................            0.08            7.83  Designated       Establishment..  One-Time.
                                                                Person.
23...........................            0.08            5.71  Designated       Establishment..  One-Time.
                                                                Person.
31-33........................            0.08            5.83  Designated       Establishment..  One-Time.
                                                                Person.
42...........................            0.08            5.73  Designated       Establishment..  One-Time.
                                                                Person.
44-45........................            0.08            3.57  Designated       Establishment..  One-Time.
                                                                Person.
48-49........................            0.08            5.05  Designated       Establishment..  One-Time.
                                                                Person.
51...........................            0.08            7.40  Designated       Establishment..  One-Time.
                                                                Person.
52...........................            0.08            6.75  Designated       Establishment..  One-Time.
                                                                Person.
53...........................            0.08            4.99  Designated       Establishment..  One-Time.
                                                                Person.

[[Page 70850]]

 
54...........................            0.08            7.97  Designated       Establishment..  One-Time.
                                                                Person.
55...........................            0.08            8.22  Designated       Establishment..  One-Time.
                                                                Person.
56...........................            0.08            4.66  Designated       Establishment..  One-Time.
                                                                Person.
61...........................            0.08            4.96  Designated       Establishment..  One-Time.
                                                                Person.
62...........................            0.08            4.66  Designated       Establishment..  One-Time.
                                                                Person.
71...........................            0.08            3.90  Designated       Establishment..  One-Time.
                                                                Person.
72...........................            0.08            2.77  Designated       Establishment..  One-Time.
                                                                Person.
81...........................            0.08            4.54  Designated       Establishment..  One-Time.
                                                                Person.
92...........................            0.08            6.09  Designated       Establishment..  One-Time.
                                                                Person.
----------------------------------------------------------------------------------------------------------------
Source: OSHA estimate derived from BLS, 2023c; BLS, 2024b; O*NET, 2023; EPA, 2002; and Rice, 2002.


                               Table VIII.C.17--Equipment-Based Unit Costs--Requirements at or Above the High Heat Trigger
                                                                         [2023$]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                           Total cost per
                   Item                         Units         Unit cost         unit                   Basis                        Frequency
--------------------------------------------------------------------------------------------------------------------------------------------------------
Warning Signs............................             1.5          $13.50          $20.25  Establishment...............  One-Time.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source: OSHA based on SafetySign.com, 2024.

F. Heat Illness and Emergency Response and Planning
    In addition to requirements for a heat emergency response plan that 
employers must include in their HIIPP, OSHA would require employers to 
undertake certain activities for any at-risk worker experiencing signs 
and symptoms of heat-related illness, including requiring immediate 
action appropriate to the severity of the illness or emergency. There 
are other methods to cool an individual experiencing a heat emergency, 
but OSHA is estimating costs here assuming that employers will 
implement the method recommended by the U.S. Army (Department of the 
Army, 2023). The agency welcomes comment on this issue and information 
on methods currently used for cooling.
    In the case of a non-emergency heat-related illness, OSHA estimates 
that a designated person will spend 45 minutes per incident monitoring 
the employee. When an employee is suspected of a heat emergency, the 
proposed standard would require immediate action to reduce body 
temperature. OSHA estimates this would take 12.5 minutes per incident 
(based on Casa et al., 2007), accompanied by an immediate call to 
emergency medical services (EMS) taking an estimated 2 minutes.\72\ For 
any employee experiencing a heat emergency working in a location that 
is off a roadway that needs EMS, a designated person will spend time 
transporting the employee to a location where EMS can reach them. OSHA 
estimated that, on average, it will take a designated person 30 minutes 
to transport an employee per incident.\73\ Finally, OSHA would require 
employers to have a way to reduce an employee's body temperature when 
necessary. OSHA assumes that employers will use two sets of four bed 
sheets \74\ that have been wetted and cooled per employee experiencing 
a heat emergency, with one set on the employee and one set in a cooler 
such that they can be swapped every three minutes. OSHA further assumes 
that employers will need to have supplies on hand to potentially handle 
two incidents concurrently. In all, this means that an employer would 
need 16 sheets (8 per individual to cool two individuals, where four 
sheets can be cooled while four are used which can then be switched and 
reused in a cycle of cooling then using the sheets) and two coolers at 
their establishment, as well as six seven-pound bags of ice \75\ for 
each 8-hour shift that meets or exceeds the initial heat trigger.
---------------------------------------------------------------------------

    \72\ OSHA estimates that a heat emergency will require less time 
from a designated person because, in a heat emergency, the affected 
employee will be transported to a medical facility by EMS rather 
than monitored for the duration at the work site.
    \73\ This time estimate includes time for the designated person 
to return to the work site.
    \74\ This assumption is based on guidance from the U.S. Army on 
treatment of heat casualties. The guidance suggests treating an ill 
person with two sheets, one to wrap their body and the other for 
their head, and to rotate between four sets of two sheets every 
three minutes (Department of the Army, 2023).
    \75\ OSHA assumes that approximately 50 percent of employers 
will make and/or store ice on their premises using existing freezers 
and/or ice machines.
---------------------------------------------------------------------------

    See table VIII.C.6. for anticipated annual incidence rates by 
sector used in this analysis. Table VIII.C.18. shows the unit costs for 
the requirements to respond to and plan for heat-related illnesses by 
severity of illness and industry sector. Table VIII.C.19. shows the 
equipment costs that employers would incur in order to perform 
emergency response procedures in the event of a heat-related illness by 
severity of illness (emergency or non-emergency).

                                Table VIII.C.18--Labor-Based Unit Costs--Heat Illness and Emergency Response and Planning
                                                                         [2023$]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                Sector                       Hours         Unit cost          Labor category                 Basis                    Frequency
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                             Medical Response--Non-Emergency
--------------------------------------------------------------------------------------------------------------------------------------------------------
11....................................            0.75          $37.37  Designated Person........  Incident................  Annual.

[[Page 70851]]

 
21....................................            0.75           61.74  Designated Person........  Incident................  Annual.
22....................................            0.75           70.46  Designated Person........  Incident................  Annual.
23....................................            0.75           51.39  Designated Person........  Incident................  Annual.
31-33.................................            0.75           52.48  Designated Person........  Incident................  Annual.
42....................................            0.75           51.58  Designated Person........  Incident................  Annual.
44-45.................................            0.75           32.17  Designated Person........  Incident................  Annual.
48-49.................................            0.75           45.44  Designated Person........  Incident................  Annual.
51....................................            0.75           66.58  Designated Person........  Incident................  Annual.
52....................................            0.75           60.73  Designated Person........  Incident................  Annual.
53....................................            0.75           44.93  Designated Person........  Incident................  Annual.
54....................................            0.75           71.75  Designated Person........  Incident................  Annual.
55....................................            0.75           73.96  Designated Person........  Incident................  Annual.
56....................................            0.75           41.97  Designated Person........  Incident................  Annual.
61....................................            0.75           44.61  Designated Person........  Incident................  Annual.
62....................................            0.75           41.94  Designated Person........  Incident................  Annual.
71....................................            0.75           35.06  Designated Person........  Incident................  Annual.
72....................................            0.75           24.93  Designated Person........  Incident................  Annual.
81....................................            0.75           40.84  Designated Person........  Incident................  Annual.
92....................................            0.75           54.83  Designated Person........  Incident................  Annual.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                               Medical Response--Emergency
--------------------------------------------------------------------------------------------------------------------------------------------------------
11....................................            0.21           10.38  Designated Person........  Incident................  Annual.
21....................................            0.21           17.15  Designated Person........  Incident................  Annual.
22....................................            0.21           19.57  Designated Person........  Incident................  Annual.
23....................................            0.21           14.28  Designated Person........  Incident................  Annual.
31-33.................................            0.21           14.58  Designated Person........  Incident................  Annual.
42....................................            0.21           14.33  Designated Person........  Incident................  Annual.
44-45.................................            0.21            8.94  Designated Person........  Incident................  Annual.
48-49.................................            0.21           12.62  Designated Person........  Incident................  Annual.
51....................................            0.21           18.50  Designated Person........  Incident................  Annual.
52....................................            0.21           16.87  Designated Person........  Incident................  Annual.
53....................................            0.21           12.48  Designated Person........  Incident................  Annual.
54....................................            0.21           19.93  Designated Person........  Incident................  Annual.
55....................................            0.21           20.55  Designated Person........  Incident................  Annual.
56....................................            0.21           11.66  Designated Person........  Incident................  Annual.
61....................................            0.21           12.39  Designated Person........  Incident................  Annual.
62....................................            0.21           11.65  Designated Person........  Incident................  Annual.
71....................................            0.21            9.74  Designated Person........  Incident................  Annual.
72....................................            0.21            6.93  Designated Person........  Incident................  Annual.
81....................................            0.21           11.34  Designated Person........  Incident................  Annual.
92....................................            0.21           15.23  Designated Person........  Incident................  Annual.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                           Contact Emergency Medical Services
--------------------------------------------------------------------------------------------------------------------------------------------------------
11....................................            0.03            1.66  Designated Person........  Incident................  Annual.
21....................................            0.03            2.74  Designated Person........  Incident................  Annual.
22....................................            0.03            3.13  Designated Person........  Incident................  Annual.
23....................................            0.03            2.28  Designated Person........  Incident................  Annual.
31-33.................................            0.03            2.33  Designated Person........  Incident................  Annual.
42....................................            0.03            2.29  Designated Person........  Incident................  Annual.
44-45.................................            0.03            1.43  Designated Person........  Incident................  Annual.
48-49.................................            0.03            2.02  Designated Person........  Incident................  Annual.
51....................................            0.03            2.96  Designated Person........  Incident................  Annual.
52....................................            0.03            2.70  Designated Person........  Incident................  Annual.
53....................................            0.03            2.00  Designated Person........  Incident................  Annual.
54....................................            0.03            3.19  Designated Person........  Incident................  Annual.
55....................................            0.03            3.29  Designated Person........  Incident................  Annual.
56....................................            0.03            1.87  Designated Person........  Incident................  Annual.
61....................................            0.03            1.98  Designated Person........  Incident................  Annual.
62....................................            0.03            1.86  Designated Person........  Incident................  Annual.
71....................................            0.03            1.56  Designated Person........  Incident................  Annual.
72....................................            0.03            1.11  Designated Person........  Incident................  Annual.
81....................................            0.03            1.82  Designated Person........  Incident................  Annual.
92....................................            0.03            2.44  Designated Person........  Incident................  Annual.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                    Transport Worker
--------------------------------------------------------------------------------------------------------------------------------------------------------
11....................................            0.50           24.92  Designated Person........  Incident................  Annual.
21....................................            0.50           41.16  Designated Person........  Incident................  Annual.
22....................................            0.50           46.97  Designated Person........  Incident................  Annual.

[[Page 70852]]

 
23....................................            0.50           34.26  Designated Person........  Incident................  Annual.
31-33.................................            0.50           34.99  Designated Person........  Incident................  Annual.
42....................................            0.50           34.39  Designated Person........  Incident................  Annual.
44-45.................................            0.50           21.45  Designated Person........  Incident................  Annual.
48-49.................................            0.50           30.30  Designated Person........  Incident................  Annual.
51....................................            0.50           44.39  Designated Person........  Incident................  Annual.
52....................................            0.50           40.49  Designated Person........  Incident................  Annual.
53....................................            0.50           29.95  Designated Person........  Incident................  Annual.
54....................................            0.50           47.83  Designated Person........  Incident................  Annual.
55....................................            0.50           49.31  Designated Person........  Incident................  Annual.
56....................................            0.50           27.98  Designated Person........  Incident................  Annual.
61....................................            0.50           29.74  Designated Person........  Incident................  Annual.
62....................................            0.50           27.96  Designated Person........  Incident................  Annual.
71....................................            0.50           23.37  Designated Person........  Incident................  Annual.
72....................................            0.50           16.62  Designated Person........  Incident................  Annual.
81....................................            0.50           27.23  Designated Person........  Incident................  Annual.
92....................................            0.50           36.55  Designated Person........  Incident................  Annual.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source: OSHA estimate derived from BLS, 2023c; BLS, 2024b; O*NET, 2023; EPA, 2002; and Rice, 2002.


                              Table VIII.C.19--Equipment-Based Unit Costs--Heat Illness and Emergency Response and Planning
                                                                         [2023$]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                   Item                         Units         Unit cost      Total cost                Basis                        Frequency
--------------------------------------------------------------------------------------------------------------------------------------------------------
Ice Sheets...............................            16.0           $9.99         $159.84  Establishment...............  One-Time.
Ice......................................             6.0        \a\ 0.69            4.14  Establishment...............  Daily at Initial Heat Trigger.
Ice Cooler...............................             2.0           31.70           63.40  Establishment...............  One-Time.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source: OSHA based on Amazon.com, Inc., 2024c; W.W. Grainger, Inc., 2024; and Walmart Inc., 2024.
\a\ Under the assumption that approximately 50 percent of employers will make and/or store ice on their premises using existing freezers and/or ice
  machines, half of the unit cost of a seven-pound bags of ice = $1.38 / 2 = $0.69 is reported.

G. Training
    The proposed standard would require employers to develop and 
implement a training program for employees and supervisors. Training 
would be required at certain frequencies, including initially (e.g., 
prior to any work at or above the initial heat trigger), annual 
refresher training, and supplemental training when necessary (e.g., 
following each heat-related incident at the work site, new job tasks, 
or changes in employer policies and procedures). OSHA assumes the 
training program would be developed and implemented by a designated 
person.
    OSHA estimates a designated person would spend four hours 
developing the initial employee training program, 30 minutes preparing 
for the initial employee training sessions, and one hour administering 
each initial training session.\76\ OSHA estimates that a designated 
person would spend 15 minutes preparing for the refresher employee 
training(s) and 30 minutes conducting each refresher employee training. 
Finally, OSHA estimates that all employees would spend one hour each 
for the initial employee training and 30 minutes each for every 
refresher employee training.
---------------------------------------------------------------------------

    \76\ OSHA expects to provide training materials and templates. 
To the extent that employers are able to incorporate and develop 
training using those materials and templates, this estimate may 
overstate the amount of time needed to develop training. OSHA 
welcomes comment on this issue, how training is generally developed, 
how long that development takes, and/or information about any other 
costs related to training development.
---------------------------------------------------------------------------

    For the supervisor and heat safety coordinator training, OSHA 
estimates that a designated person would spend four hours developing 
the initial training, 15 minutes preparing, and one hour per session to 
deliver the initial supervisor training. OSHA estimates that each 
supervisor and heat safety coordinator would spend one hour attending 
the supervisor training. For supervisor refresher training, OSHA 
estimates that a designated person would spend 15 minutes preparing for 
the refresher training and 30 minutes conducting the refresher 
training. Each supervisor and heat safety coordinator would spend 30 
minutes attending the supervisor refresher training.
    Finally, OSHA estimates that a designated person would spend 15 
minutes preparing supplemental employee training and 30 minutes 
conducting each supplemental employee training. Each employee would 
spend 30 minutes attending the employee supplemental training. For this 
analysis, OSHA assumes that these supplemental trainings would be 
conducted by one percent of establishments each year and that one 
percent of employees would attend these supplemental trainings.
    Table VIII.C.20. shows the unit costs for the training requirements 
by industry sector.

[[Page 70853]]



                                                    Table VIII.C.20--Labor-Based Unit Costs--Training
                                                                         [2023]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                Sector                       Hours         Unit cost          Labor category                 Basis                    Frequency
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                          Initial Employee Training Development
--------------------------------------------------------------------------------------------------------------------------------------------------------
11....................................             4.0         $199.32  Designated Person........  Establishment...........  One-Time.
21....................................             4.0          329.25  Designated Person........  Establishment...........  One-Time.
22....................................             4.0          375.78  Designated Person........  Establishment...........  One-Time.
23....................................             4.0          274.10  Designated Person........  Establishment...........  One-Time.
31-33.................................             4.0          279.88  Designated Person........  Establishment...........  One-Time.
42....................................             4.0          275.09  Designated Person........  Establishment...........  One-Time.
44-45.................................             4.0          171.57  Designated Person........  Establishment...........  One-Time.
48-49.................................             4.0          242.37  Designated Person........  Establishment...........  One-Time.
51....................................             4.0          355.11  Designated Person........  Establishment...........  One-Time.
52....................................             4.0          323.91  Designated Person........  Establishment...........  One-Time.
53....................................             4.0          239.62  Designated Person........  Establishment...........  One-Time.
54....................................             4.0          382.66  Designated Person........  Establishment...........  One-Time.
55....................................             4.0          394.46  Designated Person........  Establishment...........  One-Time.
56....................................             4.0          223.87  Designated Person........  Establishment...........  One-Time.
61....................................             4.0          237.94  Designated Person........  Establishment...........  One-Time.
62....................................             4.0          223.70  Designated Person........  Establishment...........  One-Time.
71....................................             4.0          187.00  Designated Person........  Establishment...........  One-Time.
72....................................             4.0          132.96  Designated Person........  Establishment...........  One-Time.
81....................................             4.0          217.82  Designated Person........  Establishment...........  One-Time.
92....................................             4.0          292.41  Designated Person........  Establishment...........  One-Time.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                      Initial Employee Training--Designated Person
--------------------------------------------------------------------------------------------------------------------------------------------------------
11....................................            1.50           74.75  Designated Person........  Establishment...........  One-Time.
21....................................            1.50          123.47  Designated Person........  Establishment...........  One-Time.
22....................................            1.50          140.92  Designated Person........  Establishment...........  One-Time.
23....................................            1.50          102.79  Designated Person........  Establishment...........  One-Time.
31-33.................................            1.50          104.96  Designated Person........  Establishment...........  One-Time.
42....................................            1.50          103.16  Designated Person........  Establishment...........  One-Time.
44-45.................................            1.50           64.34  Designated Person........  Establishment...........  One-Time.
48-49.................................            1.50           90.89  Designated Person........  Establishment...........  One-Time.
51....................................            1.50          133.17  Designated Person........  Establishment...........  One-Time.
52....................................            1.50          121.46  Designated Person........  Establishment...........  One-Time.
53....................................            1.50           89.86  Designated Person........  Establishment...........  One-Time.
54....................................            1.50          143.50  Designated Person........  Establishment...........  One-Time.
55....................................            1.50          147.92  Designated Person........  Establishment...........  One-Time.
56....................................            1.50           83.95  Designated Person........  Establishment...........  One-Time.
61....................................            1.50           89.23  Designated Person........  Establishment...........  One-Time.
62....................................            1.50           83.89  Designated Person........  Establishment...........  One-Time.
71....................................            1.50           70.12  Designated Person........  Establishment...........  One-Time.
72....................................            1.50           49.86  Designated Person........  Establishment...........  One-Time.
81....................................            1.50           81.68  Designated Person........  Establishment...........  One-Time.
92....................................            1.50          109.66  Designated Person........  Establishment...........  One-Time.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                        Initial Employee Training--At-Risk Worker
--------------------------------------------------------------------------------------------------------------------------------------------------------
11....................................             1.0           26.80  At-Risk Worker...........  Employee................  One-Time.
21....................................             1.0           46.46  At-Risk Worker...........  Employee................  One-Time.
22....................................             1.0           75.53  At-Risk Worker...........  Employee................  One-Time.
23....................................             1.0           43.95  At-Risk Worker...........  Employee................  One-Time.
31-33.................................             1.0           36.68  At-Risk Worker...........  Employee................  One-Time.
42....................................             1.0           42.34  At-Risk Worker...........  Employee................  One-Time.
44-45.................................             1.0           26.28  At-Risk Worker...........  Employee................  One-Time.
48-49.................................             1.0           33.27  At-Risk Worker...........  Employee................  One-Time.
51....................................             1.0           57.54  At-Risk Worker...........  Employee................  One-Time.
52....................................             1.0           58.24  At-Risk Worker...........  Employee................  One-Time.
53....................................             1.0           37.44  At-Risk Worker...........  Employee................  One-Time.
54....................................             1.0           76.34  At-Risk Worker...........  Employee................  One-Time.
55....................................             1.0           88.02  At-Risk Worker...........  Employee................  One-Time.
56....................................             1.0           27.56  At-Risk Worker...........  Employee................  One-Time.
61....................................             1.0           32.68  At-Risk Worker...........  Employee................  One-Time.
62....................................             1.0           28.48  At-Risk Worker...........  Employee................  One-Time.
71....................................             1.0           25.21  At-Risk Worker...........  Employee................  One-Time.
72....................................             1.0           24.13  At-Risk Worker...........  Employee................  One-Time.
81....................................             1.0           34.33  At-Risk Worker...........  Employee................  One-Time.
92....................................             1.0           50.72  At-Risk Worker...........  Employee................  One-Time.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                         Initial Supervisor Training Development
--------------------------------------------------------------------------------------------------------------------------------------------------------
11....................................             2.0           99.66  Designated Person........  Establishment...........  One-Time.

[[Page 70854]]

 
21....................................             2.0          164.63  Designated Person........  Establishment...........  One-Time.
22....................................             2.0          187.89  Designated Person........  Establishment...........  One-Time.
23....................................             2.0          137.05  Designated Person........  Establishment...........  One-Time.
31-33.................................             2.0          139.94  Designated Person........  Establishment...........  One-Time.
42....................................             2.0          137.55  Designated Person........  Establishment...........  One-Time.
44-45.................................             2.0           85.78  Designated Person........  Establishment...........  One-Time.
48-49.................................             2.0          121.18  Designated Person........  Establishment...........  One-Time.
51....................................             2.0          177.56  Designated Person........  Establishment...........  One-Time.
52....................................             2.0          161.95  Designated Person........  Establishment...........  One-Time.
53....................................             2.0          119.81  Designated Person........  Establishment...........  One-Time.
54....................................             2.0          191.33  Designated Person........  Establishment...........  One-Time.
55....................................             2.0          197.23  Designated Person........  Establishment...........  One-Time.
56....................................             2.0          111.93  Designated Person........  Establishment...........  One-Time.
61....................................             2.0          118.97  Designated Person........  Establishment...........  One-Time.
62....................................             2.0          111.85  Designated Person........  Establishment...........  One-Time.
71....................................             2.0           93.50  Designated Person........  Establishment...........  One-Time.
72....................................             2.0           66.48  Designated Person........  Establishment...........  One-Time.
81....................................             2.0          108.91  Designated Person........  Establishment...........  One-Time.
92....................................             2.0          146.21  Designated Person........  Establishment...........  One-Time.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                         Initial Supervisor Training--Supervisor
--------------------------------------------------------------------------------------------------------------------------------------------------------
11....................................            1.25           62.29  Designated Person........  Establishment...........  One-Time.
21....................................            1.25          102.89  Designated Person........  Establishment...........  One-Time.
22....................................            1.25          117.43  Designated Person........  Establishment...........  One-Time.
23....................................            1.25           85.66  Designated Person........  Establishment...........  One-Time.
31-33.................................            1.25           87.46  Designated Person........  Establishment...........  One-Time.
42....................................            1.25           85.97  Designated Person........  Establishment...........  One-Time.
44-45.................................            1.25           53.61  Designated Person........  Establishment...........  One-Time.
48-49.................................            1.25           75.74  Designated Person........  Establishment...........  One-Time.
51....................................            1.25          110.97  Designated Person........  Establishment...........  One-Time.
52....................................            1.25          101.22  Designated Person........  Establishment...........  One-Time.
53....................................            1.25           74.88  Designated Person........  Establishment...........  One-Time.
54....................................            1.25          119.58  Designated Person........  Establishment...........  One-Time.
55....................................            1.25          123.27  Designated Person........  Establishment...........  One-Time.
56....................................            1.25           69.96  Designated Person........  Establishment...........  One-Time.
61....................................            1.25           74.36  Designated Person........  Establishment...........  One-Time.
62....................................            1.25           69.91  Designated Person........  Establishment...........  One-Time.
71....................................            1.25           58.44  Designated Person........  Establishment...........  One-Time.
72....................................            1.25           41.55  Designated Person........  Establishment...........  One-Time.
81....................................            1.25           68.07  Designated Person........  Establishment...........  One-Time.
92....................................            1.25           91.38  Designated Person........  Establishment...........  One-Time.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                     Initial Supervisor Training--Designated Person
--------------------------------------------------------------------------------------------------------------------------------------------------------
11....................................             1.0           49.83  Designated Person........  Establishment...........  One-Time.
21....................................             1.0           82.31  Designated Person........  Establishment...........  One-Time.
22....................................             1.0           93.94  Designated Person........  Establishment...........  One-Time.
23....................................             1.0           68.53  Designated Person........  Establishment...........  One-Time.
31-33.................................             1.0           69.97  Designated Person........  Establishment...........  One-Time.
42....................................             1.0           68.77  Designated Person........  Establishment...........  One-Time.
44-45.................................             1.0           42.89  Designated Person........  Establishment...........  One-Time.
48-49.................................             1.0           60.59  Designated Person........  Establishment...........  One-Time.
51....................................             1.0           88.78  Designated Person........  Establishment...........  One-Time.
52....................................             1.0           80.98  Designated Person........  Establishment...........  One-Time.
53....................................             1.0           59.91  Designated Person........  Establishment...........  One-Time.
54....................................             1.0           95.67  Designated Person........  Establishment...........  One-Time.
55....................................             1.0           98.62  Designated Person........  Establishment...........  One-Time.
56....................................             1.0           55.97  Designated Person........  Establishment...........  One-Time.
61....................................             1.0           59.49  Designated Person........  Establishment...........  One-Time.
62....................................             1.0           55.92  Designated Person........  Establishment...........  One-Time.
71....................................             1.0           46.75  Designated Person........  Establishment...........  One-Time.
72....................................             1.0           33.24  Designated Person........  Establishment...........  One-Time.
81....................................             1.0           54.45  Designated Person........  Establishment...........  One-Time.
92....................................             1.0           73.10  Designated Person........  Establishment...........  One-Time.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                  Annual Employee Refresher Training--Designated Person
--------------------------------------------------------------------------------------------------------------------------------------------------------
11....................................            0.75           37.37  Designated Person........  Establishment...........  Annual.
21....................................            0.75           61.74  Designated Person........  Establishment...........  Annual.
22....................................            0.75           70.46  Designated Person........  Establishment...........  Annual.

[[Page 70855]]

 
23....................................            0.75           51.39  Designated Person........  Establishment...........  Annual.
31-33.................................            0.75           52.48  Designated Person........  Establishment...........  Annual.
42....................................            0.75           51.58  Designated Person........  Establishment...........  Annual.
44-45.................................            0.75           32.17  Designated Person........  Establishment...........  Annual.
48-49.................................            0.75           45.44  Designated Person........  Establishment...........  Annual.
51....................................            0.75           66.58  Designated Person........  Establishment...........  Annual.
52....................................            0.75           60.73  Designated Person........  Establishment...........  Annual.
53....................................            0.75           44.93  Designated Person........  Establishment...........  Annual.
54....................................            0.75           71.75  Designated Person........  Establishment...........  Annual.
55....................................            0.75           73.96  Designated Person........  Establishment...........  Annual.
56....................................            0.75           41.97  Designated Person........  Establishment...........  Annual.
61....................................            0.75           44.61  Designated Person........  Establishment...........  Annual.
62....................................            0.75           41.94  Designated Person........  Establishment...........  Annual.
71....................................            0.75           35.06  Designated Person........  Establishment...........  Annual.
72....................................            0.75           24.93  Designated Person........  Establishment...........  Annual.
81....................................            0.75           40.84  Designated Person........  Establishment...........  Annual.
92....................................            0.75           54.83  Designated Person........  Establishment...........  Annual.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                   Annual Employee Refresher Training--At-Risk Worker
--------------------------------------------------------------------------------------------------------------------------------------------------------
11....................................            0.50           13.40  At-Risk Worker...........  Employee................  Annual.
21....................................            0.50           23.23  At-Risk Worker...........  Employee................  Annual.
22....................................            0.50           37.77  At-Risk Worker...........  Employee................  Annual.
23....................................            0.50           21.97  At-Risk Worker...........  Employee................  Annual.
31-33.................................            0.50           18.34  At-Risk Worker...........  Employee................  Annual.
42....................................            0.50           21.17  At-Risk Worker...........  Employee................  Annual.
44-45.................................            0.50           13.14  At-Risk Worker...........  Employee................  Annual.
48-49.................................            0.50           16.64  At-Risk Worker...........  Employee................  Annual.
51....................................            0.50           28.77  At-Risk Worker...........  Employee................  Annual.
52....................................            0.50           29.12  At-Risk Worker...........  Employee................  Annual.
53....................................            0.50           18.72  At-Risk Worker...........  Employee................  Annual.
54....................................            0.50           38.17  At-Risk Worker...........  Employee................  Annual.
55....................................            0.50           44.01  At-Risk Worker...........  Employee................  Annual.
56....................................            0.50           13.78  At-Risk Worker...........  Employee................  Annual.
61....................................            0.50           16.34  At-Risk Worker...........  Employee................  Annual.
62....................................            0.50           14.24  At-Risk Worker...........  Employee................  Annual.
71....................................            0.50           12.61  At-Risk Worker...........  Employee................  Annual.
72....................................            0.50           12.06  At-Risk Worker...........  Employee................  Annual.
81....................................            0.50           17.16  At-Risk Worker...........  Employee................  Annual.
92....................................            0.50           25.36  At-Risk Worker...........  Employee................  Annual.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                    Annual Supervisor Refresher Training--Supervisor
--------------------------------------------------------------------------------------------------------------------------------------------------------
11....................................            0.63           31.14  Designated Person........  Establishment...........  Annual.
21....................................            0.63           51.45  Designated Person........  Establishment...........  Annual.
22....................................            0.63           58.72  Designated Person........  Establishment...........  Annual.
23....................................            0.63           42.83  Designated Person........  Establishment...........  Annual.
31-33.................................            0.63           43.73  Designated Person........  Establishment...........  Annual.
42....................................            0.63           42.98  Designated Person........  Establishment...........  Annual.
44-45.................................            0.63           26.81  Designated Person........  Establishment...........  Annual.
48-49.................................            0.63           37.87  Designated Person........  Establishment...........  Annual.
51....................................            0.63           55.49  Designated Person........  Establishment...........  Annual.
52....................................            0.63           50.61  Designated Person........  Establishment...........  Annual.
53....................................            0.63           37.44  Designated Person........  Establishment...........  Annual.
54....................................            0.63           59.79  Designated Person........  Establishment...........  Annual.
55....................................            0.63           61.64  Designated Person........  Establishment...........  Annual.
56....................................            0.63           34.98  Designated Person........  Establishment...........  Annual.
61....................................            0.63           37.18  Designated Person........  Establishment...........  Annual.
62....................................            0.63           34.95  Designated Person........  Establishment...........  Annual.
71....................................            0.63           29.22  Designated Person........  Establishment...........  Annual.
72....................................            0.63           20.78  Designated Person........  Establishment...........  Annual.
81....................................            0.63           34.03  Designated Person........  Establishment...........  Annual.
92....................................            0.63           45.69  Designated Person........  Establishment...........  Annual.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                 Annual Supervisor Refresher Training--Designated Person
--------------------------------------------------------------------------------------------------------------------------------------------------------
11....................................             0.5           24.92  Designated Person........  Establishment...........  Annual.
21....................................             0.5           41.16  Designated Person........  Establishment...........  Annual.
22....................................             0.5           46.97  Designated Person........  Establishment...........  Annual.
23....................................             0.5           34.26  Designated Person........  Establishment...........  Annual.
31-33.................................             0.5           34.99  Designated Person........  Establishment...........  Annual.

[[Page 70856]]

 
42....................................             0.5           34.39  Designated Person........  Establishment...........  Annual.
44-45.................................             0.5           21.45  Designated Person........  Establishment...........  Annual.
48-49.................................             0.5           30.30  Designated Person........  Establishment...........  Annual.
51....................................             0.5           44.39  Designated Person........  Establishment...........  Annual.
52....................................             0.5           40.49  Designated Person........  Establishment...........  Annual.
53....................................             0.5           29.95  Designated Person........  Establishment...........  Annual.
54....................................             0.5           47.83  Designated Person........  Establishment...........  Annual.
55....................................             0.5           49.31  Designated Person........  Establishment...........  Annual.
56....................................             0.5           27.98  Designated Person........  Establishment...........  Annual.
61....................................             0.5           29.74  Designated Person........  Establishment...........  Annual.
62....................................             0.5           27.96  Designated Person........  Establishment...........  Annual.
71....................................             0.5           23.37  Designated Person........  Establishment...........  Annual.
72....................................             0.5           16.62  Designated Person........  Establishment...........  Annual.
81....................................             0.5           27.23  Designated Person........  Establishment...........  Annual.
92....................................             0.5           36.55  Designated Person........  Establishment...........  Annual.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                               Supplemental Employee Refresher Training--Designated Person
--------------------------------------------------------------------------------------------------------------------------------------------------------
11....................................            0.75           37.37  Designated Person........  Establishment...........  Annual.
21....................................            0.75           61.74  Designated Person........  Establishment...........  Annual.
22....................................            0.75           70.46  Designated Person........  Establishment...........  Annual.
23....................................            0.75           51.39  Designated Person........  Establishment...........  Annual.
31-33.................................            0.75           52.48  Designated Person........  Establishment...........  Annual.
42....................................            0.75           51.58  Designated Person........  Establishment...........  Annual.
44-45.................................            0.75           32.17  Designated Person........  Establishment...........  Annual.
48-49.................................            0.75           45.44  Designated Person........  Establishment...........  Annual.
51....................................            0.75           66.58  Designated Person........  Establishment...........  Annual.
52....................................            0.75           60.73  Designated Person........  Establishment...........  Annual.
53....................................            0.75           44.93  Designated Person........  Establishment...........  Annual.
54....................................            0.75           71.75  Designated Person........  Establishment...........  Annual.
55....................................            0.75           73.96  Designated Person........  Establishment...........  Annual.
56....................................            0.75           41.97  Designated Person........  Establishment...........  Annual.
61....................................            0.75           44.61  Designated Person........  Establishment...........  Annual.
62....................................            0.75           41.94  Designated Person........  Establishment...........  Annual.
71....................................            0.75           35.06  Designated Person........  Establishment...........  Annual.
72....................................            0.75           24.93  Designated Person........  Establishment...........  Annual.
81....................................            0.75           40.84  Designated Person........  Establishment...........  Annual.
92....................................            0.75           54.83  Designated Person........  Establishment...........  Annual.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                Supplemental Employee Refresher Training--At-Risk Worker
--------------------------------------------------------------------------------------------------------------------------------------------------------
11....................................            0.50           13.40  At-Risk Worker...........  Employee................  Annual.
21....................................            0.50           23.23  At-Risk Worker...........  Employee................  Annual.
22....................................            0.50           37.77  At-Risk Worker...........  Employee................  Annual.
23....................................            0.50           21.97  At-Risk Worker...........  Employee................  Annual.
31-33.................................            0.50           18.34  At-Risk Worker...........  Employee................  Annual.
42....................................            0.50           21.17  At-Risk Worker...........  Employee................  Annual.
44-45.................................            0.50           13.14  At-Risk Worker...........  Employee................  Annual.
48-49.................................            0.50           16.64  At-Risk Worker...........  Employee................  Annual.
51....................................            0.50           28.77  At-Risk Worker...........  Employee................  Annual.
52....................................            0.50           29.12  At-Risk Worker...........  Employee................  Annual.
53....................................            0.50           18.72  At-Risk Worker...........  Employee................  Annual.
54....................................            0.50           38.17  At-Risk Worker...........  Employee................  Annual.
55....................................            0.50           44.01  At-Risk Worker...........  Employee................  Annual.
56....................................            0.50           13.78  At-Risk Worker...........  Employee................  Annual.
61....................................            0.50           16.34  At-Risk Worker...........  Employee................  Annual.
62....................................            0.50           14.24  At-Risk Worker...........  Employee................  Annual.
71....................................            0.50           12.61  At-Risk Worker...........  Employee................  Annual.
72....................................            0.50           12.06  At-Risk Worker...........  Employee................  Annual.
81....................................            0.50           17.16  At-Risk Worker...........  Employee................  Annual.
92....................................            0.50           25.36  At-Risk Worker...........  Employee................  Annual.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source: OSHA estimate derived from BLS, 2023c; BLS, 2024b; O*NET, 2023; EPA, 2002; and Rice, 2002.

H. Recordkeeping
    The proposed standard would require that indoor work area 
measurements be retained for 6 months. OSHA assumes that employers 
would purchase a wireless temperature and humidity data logger 
described in section VIII.C.IV.C. (with the costs accounted for there) 
to meet this requirement. Since employers would purchase data loggers 
that can automatically record the heat index measurements in and around 
a work site, OSHA assumes employers would

[[Page 70857]]

incur no additional cost to comply with this recordkeeping requirement.
V. Estimated Total Costs of Compliance
    This section summarizes the estimated total costs of compliance 
with the proposed standard. The total costs are generally calculated by 
multiplying the basis for each cost (the number of affected 
establishments or affected employees as shown in Section VIII.B. 
Profile of Affected Industries) by the unit costs shown in section 
VIII.C.IV. Each of these costs are then multiplied by their 
corresponding non-compliance rates (as shown in section VIII.C.II.A.) 
to determine total compliance-adjusted costs.
    Many costs in this analysis are incurred one time, and most others 
are either annual or can be annualized based on days of exposure or 
events that happen multiple times per year. For the purposes of this 
cost analysis, total costs are annualized based on several assumptions, 
such as estimates of the number of hours at or above both heat triggers 
and incidence rates for HRIs and heat-related fatalities (see Section 
VIII.C.II., Cost Assumptions for additional detail). The exceptions are 
the identification and evaluation of heat-exposed work areas for indoor 
work sites and the corresponding employee involvement in that work area 
evaluation, which are assumed to impact 20 percent of establishments 
each year. Based on that assumption, OSHA estimates that these costs 
are both incurred every five years. In order to present compliance 
costs and benefits estimates on a consistent basis across proposed 
standard provisions, they are presented as annualized costs.
    For each provision described below, this analysis annualizes one-
time costs using a 2 percent discount rate over a 10-year period. For 
the two costs incurred every five years, OSHA calculated the present 
value of these costs assuming that they would be incurred in the first 
year and the sixth year after adoption of the proposed standard using a 
2 percent discount rate. Using the present value of these costs, OSHA 
then annualized using a 2 percent discount rate. Annualized one-time 
and annual costs, plus the annualized period costs, are then summed to 
estimate total annualized costs.
    For each provision in the proposed standard, OSHA also calculated 
the estimated total annualized undiscounted costs, using the same 
method as above but assuming a 0 percent discount rate over a 10-year 
period.
A. Rule Familiarization
    All affected establishments would incur rule familiarization costs. 
To calculate the total cost of rule familiarization, OSHA multiplies 
the number of affected establishments from table VIII.B.12. in Section 
VIII.B., Profile of Affected Industries, by the unit costs presented in 
table VIII.C.8. As all affected employers incur this cost, no 
compliance adjustment is necessary. Table VIII.C.21. shows the 
annualized one-time, annual, and total annualized costs for each of 
these requirements by industry category, discounted (2 percent over a 
10-year period) and undiscounted.

                                                   Table VIII.C.21--Total Costs--Rule Familiarization
                                                                         [2023$]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                          One-time annualized                                 Total annualized
                       Industry category                        --------------------------------------    Annual   -------------------------------------
                                                                         0%                 2%                              0%                 2%
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing.............................           $527,603           $587,362           $0           $527,603           $587,362
Building Materials and Equipment Suppliers.....................            104,224            116,029            0            104,224            116,029
Commercial Kitchens............................................            846,038            941,865            0            846,038            941,865
Construction...................................................          5,074,534          5,649,302            0          5,074,534          5,649,302
Drycleaning and Commercial Laundries...........................             83,921             93,426            0             83,921             93,426
Landscaping and Facilities Support.............................            342,744            381,565            0            342,744            381,565
Maintenance and Repair.........................................            510,799            568,655            0            510,799            568,655
Manufacturing..................................................            922,558          1,027,052            0            922,558          1,027,052
Oil and Gas....................................................            180,543            200,992            0            180,543            200,992
Postal and Delivery Services...................................            227,857            253,665            0            227,857            253,665
Recreation and Amusement.......................................            215,821            240,265            0            215,821            240,265
Sanitation and Waste Removal...................................             19,362             21,555            0             19,362             21,555
Telecommunications.............................................             73,042             81,316            0             73,042             81,316
Temporary Help Services........................................             40,721             45,333            0             40,721             45,333
Transportation.................................................            836,631            931,392            0            836,631            931,392
Utilities......................................................            173,581            193,241            0            173,581            193,241
Warehousing....................................................             86,490             96,286            0             86,490             96,286
Non-Core.......................................................          5,076,915          5,651,954            0          5,076,915          5,651,954
                                                                ----------------------------------------------------------------------------------------
    Total......................................................         15,343,382         17,081,254            0         15,343,382         17,081,254
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source: OSHA estimate.
Note: Due to rounding, figures in the columns and rows may not sum to the totals shown.

B. Heat Injury and Illness Prevention Plan (HIIPP)
    All affected establishments would incur costs for developing a 
HIIPP. For those establishments that already have a HIIPP, they are 
expected to review their HIIPP and make any modifications necessary to 
match the requirements outlined in this proposed standard. Section 
VIII.C.II.A. discusses the percentages of establishments with HIIPPs 
already in place in certain industries and States.
    The proposed standard does not require establishments with ten or 
less employees to develop their HIIPP in writing. For the purpose of 
this analysis, OSHA assumed that all affected establishments with ten 
or less employees would choose to use OSHA's template to guide their 
development of an unwritten HIIPP. Of the remaining establishments that 
do not have an existing HIIPP and have more than ten employees, OSHA 
assumes that, as discussed in section VIII.C.IV.B., 90 percent of these 
establishments without an existing plan would choose the less 
burdensome option of using OSHA's

[[Page 70858]]

template, while the other 10 percent would write their HIIPP from 
scratch.\77\
---------------------------------------------------------------------------

    \77\ The percentage of establishments overall that will choose 
to write a HIIPP from scratch as reported in section VIII.C.IV.B. is 
estimated using these assumptions. The percentage of establishments 
choosing to write the HIIPP from scratch is equal to the estimated 
percentage of establishments without an existing HIIPP (50 percent) 
multiplied by the percentage of establishments without a HIIPP that 
will write from scratch (10 percent), resulting in an estimate of 5 
percent.
---------------------------------------------------------------------------

    Affected establishments would have to review and update their 
HIIPPs annually. The time to perform this requirement (one hour) does 
not depend on the option that establishments choose when initially 
developing their HIIPP.
    The proposed standard would also require that non-managerial 
employees be involved in the development, review, and update of the 
HIIPP. As discussed in section VIII.C.IV.B., OSHA assumed that four 
employees per establishment would spend one hour providing input on the 
development of the HIIPP and 20 minutes on the review and update of 
their establishments' HIIPP. These time estimates are assumed to be the 
same regardless of the option that the establishment chooses when 
developing, reviewing, and updating their HIIPP. Table VIII.C.22. shows 
the annualized one-time, annual, and total annualized costs for each of 
these requirements by industry category, discounted (2 percent over a 
10-year period) and undiscounted.

                                          Table VIII.C.22--Total Costs--Heat Injury and Illness Prevention Plan
                                                                         [2023$]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                          One-time annualized                                 Total annualized
                       Industry category                        --------------------------------------    Annual   -------------------------------------
                                                                         0%                 2%                              0%                 2%
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                Write HIIPP from Scratch
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing.............................           $571,516           $636,249           $0           $571,516           $636,249
Building Materials and Equipment Suppliers.....................             79,076             88,032            0             79,076             88,032
Commercial Kitchens............................................            687,870            765,782            0            687,870            765,782
Construction...................................................            736,175            819,558            0            736,175            819,558
Drycleaning and Commercial Laundries...........................             34,901             38,854            0             34,901             38,854
Landscaping and Facilities Support.............................            147,130            163,795            0            147,130            163,795
Maintenance and Repair.........................................            149,423            166,347            0            149,423            166,347
Manufacturing..................................................            316,372            352,206            0            316,372            352,206
Oil and Gas....................................................            123,156            137,105            0            123,156            137,105
Postal and Delivery Services...................................            287,792            320,388            0            287,792            320,388
Recreation and Amusement.......................................            123,726            137,740            0            123,726            137,740
Sanitation and Waste Removal...................................             13,733             15,288            0             13,733             15,288
Telecommunications.............................................             90,704            100,978            0             90,704            100,978
Temporary Help Services........................................             41,207             45,874            0             41,207             45,874
Transportation.................................................            336,424            374,530            0            336,424            374,530
Utilities......................................................            196,764            219,050            0            196,764            219,050
Warehousing....................................................             99,757            111,055            0             99,757            111,055
Non-Core.......................................................          4,758,864          5,297,878            0          4,758,864          5,297,878
                                                                ----------------------------------------------------------------------------------------
    Subtotal...................................................          8,794,588          9,790,710            0          8,794,588          9,790,710
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                     Review and Modify HIIPP--Existing Plan in Place
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing.............................            602,197            670,405            0            602,197            670,405
Building Materials and Equipment Suppliers.....................             71,235             79,303            0             71,235             79,303
Commercial Kitchens............................................            640,861            713,448            0            640,861            713,448
Construction...................................................          1,869,454          2,081,199            0          1,869,454          2,081,199
Drycleaning and Commercial Laundries...........................             30,363             33,802            0             30,363             33,802
Landscaping and Facilities Support.............................            127,030            141,418            0            127,030            141,418
Maintenance and Repair.........................................            134,784            150,051            0            134,784            150,051
Manufacturing..................................................            862,318            959,989            0            862,318            959,989
Oil and Gas....................................................            104,531            116,371            0            104,531            116,371
Postal and Delivery Services...................................            256,231            285,253            0            256,231            285,253
Recreation and Amusement.......................................            111,630            124,274            0            111,630            124,274
Sanitation and Waste Removal...................................             12,418             13,825            0             12,418             13,825
Telecommunications.............................................             81,702             90,956            0             81,702             90,956
Temporary Help Services........................................             36,857             41,032            0             36,857             41,032
Transportation.................................................            348,769            388,272            0            348,769            388,272
Utilities......................................................            172,636            192,190            0            172,636            192,190
Warehousing....................................................             89,576             99,722            0             89,576             99,722
Non-Core.......................................................            645,831            718,981            0            645,831            718,981
                                                                ----------------------------------------------------------------------------------------
    Subtotal...................................................          6,198,424          6,900,490            0          6,198,424          6,900,490
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                   Use HIIPP Template
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing.............................          1,028,729          1,145,248            0          1,028,729          1,145,248
Building Materials and Equipment Suppliers.....................            142,336            158,458            0            142,336            158,458
Commercial Kitchens............................................          1,238,166          1,378,407            0          1,238,166          1,378,407
Construction...................................................          1,325,114          1,475,204            0          1,325,114          1,475,204
Drycleaning and Commercial Laundries...........................             62,822             69,938            0             62,822             69,938
Landscaping and Facilities Support.............................            264,834            294,830            0            264,834            294,830
Maintenance and Repair.........................................            268,961            299,425            0            268,961            299,425
Manufacturing..................................................            569,469            633,971            0            569,469            633,971
Oil and Gas....................................................            221,681            246,789            0            221,681            246,789
Postal and Delivery Services...................................            518,025            576,699            0            518,025            576,699
Recreation and Amusement.......................................            222,707            247,932            0            222,707            247,932
Sanitation and Waste Removal...................................             24,719             27,519            0             24,719             27,519

[[Page 70859]]

 
Telecommunications.............................................            163,268            181,761            0            163,268            181,761
Temporary Help Services........................................             74,172             82,574            0             74,172             82,574
Transportation.................................................            605,564            674,153            0            605,564            674,153
Utilities......................................................            354,175            394,291            0            354,175            394,291
Warehousing....................................................            179,562            199,900            0            179,562            199,900
Non-Core.......................................................          8,565,954          9,536,180            0          8,565,954          9,536,180
                                                                ----------------------------------------------------------------------------------------
    Subtotal...................................................         15,830,259         17,623,278            0         15,830,259         17,623,278
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                    No Written HIIPP
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing.............................            384,875            428,468            0            384,875            428,468
Building Materials and Equipment Suppliers.....................            197,485            219,853            0            197,485            219,853
Commercial Kitchens............................................          1,441,614          1,604,899            0          1,441,614          1,604,899
Construction...................................................         16,325,441         18,174,547            0         16,325,441         18,174,547
Drycleaning and Commercial Laundries...........................            240,566            267,814            0            240,566            267,814
Landscaping and Facilities Support.............................            971,555          1,081,599            0            971,555          1,081,599
Maintenance and Repair.........................................          1,628,310          1,812,741            0          1,628,310          1,812,741
Manufacturing..................................................          1,888,694          2,102,618            0          1,888,694          2,102,618
Oil and Gas....................................................            390,715            434,970            0            390,715            434,970
Postal and Delivery Services...................................            117,737            131,073            0            117,737            131,073
Recreation and Amusement.......................................            519,705            578,570            0            519,705            578,570
Sanitation and Waste Removal...................................             39,269             43,717            0             39,269             43,717
Telecommunications.............................................             40,508             45,096            0             40,508             45,096
Temporary Help Services........................................             48,969             54,515            0             48,969             54,515
Transportation.................................................          2,339,927          2,604,960            0          2,339,927          2,604,960
Utilities......................................................            155,752            173,394            0            155,752            173,394
Warehousing....................................................             69,627             77,514            0             69,627             77,514
Non-Core.......................................................         12,929,181         14,393,608            0         12,929,181         14,393,608
                                                                ----------------------------------------------------------------------------------------
    Subtotal...................................................         39,729,931         44,229,952            0         39,729,931         44,229,952
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                         HIIPP Development Involvement--Employee
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing.............................            851,195            947,606            0            851,195            947,606
Building Materials and Equipment Suppliers.....................            192,469            214,269            0            192,469            214,269
Commercial Kitchens............................................          1,817,682          2,023,562            0          1,817,682          2,023,562
Construction...................................................          9,833,544         10,947,344            0          9,833,544         10,947,344
Drycleaning and Commercial Laundries...........................            158,699            176,674            0            158,699            176,674
Landscaping and Facilities Support.............................            576,337            641,616            0            576,337            641,616
Maintenance and Repair.........................................            965,955          1,075,364            0            965,955          1,075,364
Manufacturing..................................................          1,450,926          1,615,265            0          1,450,926          1,615,265
Oil and Gas....................................................            304,839            339,367            0            304,839            339,367
Postal and Delivery Services...................................            375,365            417,881            0            375,365            417,881
Recreation and Amusement.......................................            354,289            394,418            0            354,289            394,418
Sanitation and Waste Removal...................................             28,608             31,849            0             28,608             31,849
Telecommunications.............................................            142,022            158,108            0            142,022            158,108
Temporary Help Services........................................             60,166             66,981            0             60,166             66,981
Transportation.................................................          1,378,241          1,534,347            0          1,378,241          1,534,347
Utilities......................................................            418,672            466,093            0            418,672            466,093
Warehousing....................................................            142,480            158,618            0            142,480            158,618
Non-Core.......................................................         10,068,354         11,208,749            0         10,068,354         11,208,749
                                                                ----------------------------------------------------------------------------------------
    Subtotal...................................................         29,119,844         32,418,111            0         29,119,844         32,418,111
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                 Review and Update HIIPP
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing.............................                  0                  0    2,638,013          2,638,013          2,638,013
Building Materials and Equipment Suppliers.....................                  0                  0      521,118            521,118            521,118
Commercial Kitchens............................................                  0                  0    4,230,189          4,230,189          4,230,189
Construction...................................................                  0                  0   25,372,668         25,372,668         25,372,668
Drycleaning and Commercial Laundries...........................                  0                  0      419,603            419,603            419,603
Landscaping and Facilities Support.............................                  0                  0    1,713,720          1,713,720          1,713,720
Maintenance and Repair.........................................                  0                  0    2,553,994          2,553,994          2,553,994
Manufacturing..................................................                  0                  0    4,612,791          4,612,791          4,612,791
Oil and Gas....................................................                  0                  0      902,716            902,716            902,716
Postal and Delivery Services...................................                  0                  0    1,139,285          1,139,285          1,139,285
Recreation and Amusement.......................................                  0                  0    1,079,103          1,079,103          1,079,103
Sanitation and Waste Removal...................................                  0                  0       96,811             96,811             96,811
Telecommunications.............................................                  0                  0      365,212            365,212            365,212
Temporary Help Services........................................                  0                  0      203,603            203,603            203,603
Transportation.................................................                  0                  0    4,183,154          4,183,154          4,183,154
Utilities......................................................                  0                  0      867,903            867,903            867,903
Warehousing....................................................                  0                  0      432,448            432,448            432,448
Non-Core.......................................................                  0                  0   25,384,577         25,384,577         25,384,577
                                                                ----------------------------------------------------------------------------------------
    Subtotal...................................................                  0                  0   76,716,909         76,716,909         76,716,909
--------------------------------------------------------------------------------------------------------------------------------------------------------

[[Page 70860]]

 
                                                      HIIPP Review and Update Involvement--Employee
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing.............................                  0                  0    2,837,318          2,837,318          2,837,318
Building Materials and Equipment Suppliers.....................                  0                  0      641,563            641,563            641,563
Commercial Kitchens............................................                  0                  0    6,058,940          6,058,940          6,058,940
Construction...................................................                  0                  0   32,778,482         32,778,482         32,778,482
Drycleaning and Commercial Laundries...........................                  0                  0      528,998            528,998            528,998
Landscaping and Facilities Support.............................                  0                  0    1,921,123          1,921,123          1,921,123
Maintenance and Repair.........................................                  0                  0    3,219,849          3,219,849          3,219,849
Manufacturing..................................................                  0                  0    4,836,419          4,836,419          4,836,419
Oil and Gas....................................................                  0                  0    1,016,130          1,016,130          1,016,130
Postal and Delivery Services...................................                  0                  0    1,251,217          1,251,217          1,251,217
Recreation and Amusement.......................................                  0                  0    1,180,963          1,180,963          1,180,963
Sanitation and Waste Removal...................................                  0                  0       95,362             95,362             95,362
Telecommunications.............................................                  0                  0      473,407            473,407            473,407
Temporary Help Services........................................                  0                  0      200,554            200,554            200,554
Transportation.................................................                  0                  0    4,594,136          4,594,136          4,594,136
Utilities......................................................                  0                  0    1,395,573          1,395,573          1,395,573
Warehousing....................................................                  0                  0      474,934            474,934            474,934
Non-Core.......................................................                  0                  0   33,561,180         33,561,180         33,561,180
                                                                ----------------------------------------------------------------------------------------
    Subtotal...................................................                  0                  0   97,066,147         97,066,147         97,066,147
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                          Total
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing.............................          3,438,511          3,827,975    5,475,331          8,913,842          9,303,306
Building Materials and Equipment Suppliers.....................            682,600            759,915    1,162,682          1,845,282          1,922,597
Commercial Kitchens............................................          5,826,193          6,486,098   10,289,129         16,115,322         16,775,228
Construction...................................................         30,089,729         33,497,850   58,151,149         88,240,878         91,649,000
Drycleaning and Commercial Laundries...........................            527,352            587,083      948,600          1,475,952          1,535,683
Landscaping and Facilities Support.............................          2,086,886          2,323,258    3,634,843          5,721,729          5,958,101
Maintenance and Repair.........................................          3,147,433          3,503,928    5,773,844          8,921,277          9,277,772
Manufacturing..................................................          5,087,780          5,664,048    9,449,210         14,536,989         15,113,258
Oil and Gas....................................................          1,144,922          1,274,601    1,918,846          3,063,767          3,193,447
Postal and Delivery Services...................................          1,555,149          1,731,294    2,390,502          3,945,651          4,121,796
Recreation and Amusement.......................................          1,332,058          1,482,934    2,260,066          3,592,124          3,743,000
Sanitation and Waste Removal...................................            118,748            132,198      192,173            310,921            324,371
Telecommunications.............................................            518,204            576,898      838,619          1,356,823          1,415,518
Temporary Help Services........................................            261,372            290,976      404,158            665,530            695,134
Transportation.................................................          5,008,925          5,576,262    8,777,289         13,786,214         14,353,551
Utilities......................................................          1,297,999          1,445,017    2,263,476          3,561,475          3,708,493
Warehousing....................................................            581,002            646,809      907,382          1,488,384          1,554,191
Non-Core.......................................................         36,968,184         41,155,395   58,945,757         95,913,940        100,101,152
                                                                ----------------------------------------------------------------------------------------
    Total......................................................         99,673,046        110,962,542  173,783,056        273,456,102        284,745,597
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source: OSHA estimate.
Note: Due to rounding, figures in the columns and rows may not sum to the totals shown.

C. Identifying Heat Hazards
    Establishments would be expected to monitor environmental 
conditions in and around work areas under the proposed standard for 
both indoor and outdoor work sites. As outlined in section 
VIII.C.IV.C., establishments with outdoor work sites could track local 
forecasts to meet this requirement, while establishments with indoor 
work sites are assumed to use temperature and data loggers to monitor 
environmental conditions. For this analysis, OSHA assumes one work area 
per establishment. OSHA estimates the number of establishments with 
outdoor and indoor work areas by estimating the percentage of employees 
in each industry that are estimated as indoor and outdoor employees 
affected by the proposed standard. OSHA multiplies the total number of 
affected establishments by the percentages of indoor and outdoor 
employees to determine the number of indoor and outdoor establishments 
and then multiplies these counts of indoor and outdoor establishments 
by their respective unit costs for indoor and outdoor environmental 
monitoring (with the unit costs for outdoor establishments being lower 
than for indoor establishments).
    Indoor establishments would also need to identify work areas that 
pose heat-related risks to employees. OSHA assumes that 20 percent of 
establishments will need to reevaluate work areas due to changes to 
work processes that may result in increased heat-related exposure for 
employees every year. OSHA therefore has estimated that this indoor 
work area evaluation would be incurred every five years at each 
establishment. Similar to the development and review of the HIIPP, the 
proposed standard would require employee involvement in these work-area 
evaluations. OSHA again assumes that four employees per establishment 
would make up a representative sample of employees that could provide 
input. Since these work-area evaluations are expected to occur every 
five years, OSHA assumed that the cost for these work-area evaluations 
would occur in the first and sixth years after the proposed standard's 
implementation. OSHA determined the present value of these costs using 
a 2 percent discount rate. Once adjusted for compliance, OSHA 
annualized the present value of these costs for inclusion in the total 
annualized costs for this provision.
    Table VIII.C.23. shows the annualized costs for each of these 
requirements by industry category, discounted (2 percent

[[Page 70861]]

over a 10-year period) and undiscounted.

                                                 Table VIII.C.23--Total Costs--Identifying Heat Hazards
                                                                         [2023$]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                One-time annualized          Periodic costs annualized                           Total annualized
            Industry category            ----------------------------------------------------------------     Annual     -------------------------------
                                                0%              2%              0%              2%                              0%              2%
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                            Outdoor Environmental Monitoring
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing......              $0              $0              $0              $0      $1,375,617      $1,375,617      $1,375,617
Building Materials and Equipment                       0               0               0               0         158,176         158,176         158,176
 Suppliers..............................
Commercial Kitchens.....................               0               0               0               0         281,211         281,211         281,211
Construction............................               0               0               0               0      10,052,936      10,052,936      10,052,936
Drycleaning and Commercial Laundries....               0               0               0               0          80,978          80,978          80,978
Landscaping and Facilities Support......               0               0               0               0       1,064,766       1,064,766       1,064,766
Maintenance and Repair..................               0               0               0               0         899,249         899,249         899,249
Manufacturing...........................               0               0               0               0         531,117         531,117         531,117
Oil and Gas.............................               0               0               0               0         496,105         496,105         496,105
Postal and Delivery Services............               0               0               0               0         437,122         437,122         437,122
Recreation and Amusement................               0               0               0               0         485,898         485,898         485,898
Sanitation and Waste Removal............               0               0               0               0          40,070          40,070          40,070
Telecommunications......................               0               0               0               0         156,702         156,702         156,702
Temporary Help Services.................               0               0               0               0          53,412          53,412          53,412
Transportation..........................               0               0               0               0       1,701,945       1,701,945       1,701,945
Utilities...............................               0               0               0               0         404,225         404,225         404,225
Warehousing.............................               0               0               0               0          99,663          99,663          99,663
Non-Core................................               0               0               0               0       8,653,930       8,653,930       8,653,930
                                         ---------------------------------------------------------------------------------------------------------------
    Subtotal............................               0               0               0               0      26,973,121      26,973,121      26,973,121
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                             Indoor Environmental Monitoring
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing......               0               0               0               0       5,185,108       5,185,108       5,185,108
Building Materials and Equipment                       0               0               0               0       2,683,488       2,683,488       2,683,488
 Suppliers..............................
Commercial Kitchens.....................               0               0               0               0      30,781,175      30,781,175      30,781,175
Construction............................               0               0               0               0      22,515,231      22,515,231      22,515,231
Drycleaning and Commercial Laundries....               0               0               0               0       2,699,251       2,699,251       2,699,251
Landscaping and Facilities Support......               0               0               0               0       4,713,180       4,713,180       4,713,180
Maintenance and Repair..................               0               0               0               0      11,923,927      11,923,927      11,923,927
Manufacturing...........................               0               0               0               0      10,319,923      10,319,923      10,319,923
Oil and Gas.............................               0               0               0               0       2,870,853       2,870,853       2,870,853
Postal and Delivery Services............               0               0               0               0       4,943,180       4,943,180       4,943,180
Recreation and Amusement................               0               0               0               0       3,895,764       3,895,764       3,895,764
Sanitation and Waste Removal............               0               0               0               0         386,155         386,155         386,155
Telecommunications......................               0               0               0               0       1,423,714       1,423,714       1,423,714
Temporary Help Services.................               0               0               0               0       1,134,702       1,134,702       1,134,702
Transportation..........................               0               0               0               0      14,040,680      14,040,680      14,040,680
Utilities...............................               0               0               0               0       3,101,788       3,101,788       3,101,788
Warehousing.............................               0               0               0               0       2,565,146       2,565,146       2,565,146
Non-Core................................               0               0               0               0     215,676,858     215,676,858     215,676,858
                                         ---------------------------------------------------------------------------------------------------------------
    Subtotal............................               0               0               0               0     340,860,123     340,860,123     340,860,123
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                    Indoor Identification of Heat-Exposed Work Areas
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing......               0               0         434,176         451,540               0         434,176         451,540
Building Materials and Equipment                       0               0         196,825         204,696               0         196,825         204,696
 Suppliers..............................
Commercial Kitchens.....................               0               0       2,237,077       2,326,542               0       2,237,077       2,326,542
Construction............................               0               0         969,517       1,008,290               0         969,517       1,008,290
Drycleaning and Commercial Laundries....               0               0         193,662         201,407               0         193,662         201,407
Landscaping and Facilities Support......               0               0         339,167         352,731               0         339,167         352,731
Maintenance and Repair..................               0               0         873,563         908,498               0         873,563         908,498
Manufacturing...........................               0               0         352,835         366,946               0         352,835         366,946
Oil and Gas.............................               0               0         201,310         209,361               0         201,310         209,361
Postal and Delivery Services............               0               0         362,718         377,224               0         362,718         377,224
Recreation and Amusement................               0               0         288,093         299,614               0         288,093         299,614
Sanitation and Waste Removal............               0               0          28,493          29,633               0          28,493          29,633
Telecommunications......................               0               0         104,314         108,485               0         104,314         108,485
Temporary Help Services.................               0               0          83,063          86,385               0          83,063          86,385
Transportation..........................               0               0       1,134,479       1,179,850               0       1,134,479       1,179,850
Utilities...............................               0               0         167,121         173,804               0         167,121         173,804
Warehousing.............................               0               0         186,866         194,339               0         186,866         194,339
Non-Core................................               0               0      15,801,702      16,433,646               0      15,801,702      16,433,646
                                         ---------------------------------------------------------------------------------------------------------------
    Subtotal............................               0               0      23,954,982      24,912,993               0      23,954,982      24,912,993
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                             Work Area Evaluation--Employee
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing......               0               0         116,745         121,414               0         116,745         121,414
Building Materials and Equipment                       0               0          60,542          62,963               0          60,542          62,963
 Suppliers..............................
Commercial Kitchens.....................               0               0         834,492         867,865               0         834,492         867,865
Construction............................               0               0       1,674,440       1,741,404               0       1,674,440       1,741,404
Drycleaning and Commercial Laundries....               0               0          61,038          63,479               0          61,038          63,479

[[Page 70862]]

 
Landscaping and Facilities Support......               0               0          95,514          99,334               0          95,514          99,334
Maintenance and Repair..................               0               0         275,328         286,338               0         275,328         286,338
Manufacturing...........................               0               0         601,334         625,383               0         601,334         625,383
Oil and Gas.............................               0               0          56,627          58,892               0          56,627          58,892
Postal and Delivery Services............               0               0          99,588         103,571               0          99,588         103,571
Recreation and Amusement................               0               0          78,775          81,925               0          78,775          81,925
Sanitation and Waste Removal............               0               0           7,017           7,297               0           7,017           7,297
Telecommunications......................               0               0          33,804          35,156               0          33,804          35,156
Temporary Help Services.................               0               0          20,455          21,273               0          20,455          21,273
Transportation..........................               0               0         311,485         323,942               0         311,485         323,942
Utilities...............................               0               0          90,893          94,528               0          90,893          94,528
Warehousing.............................               0               0          51,306          53,358               0          51,306          53,358
Non-Core................................               0               0       2,926,926       3,043,980               0       2,926,926       3,043,980
                                         ---------------------------------------------------------------------------------------------------------------
    Subtotal............................               0               0       7,396,309       7,692,103               0       7,396,309       7,692,103
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                              Monitoring Equipment--Indoor
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing......         118,862         132,325               0               0               0         118,862         132,325
Building Materials and Equipment                  57,453          63,961               0               0               0          57,453          63,961
 Suppliers..............................
Commercial Kitchens.....................       1,048,813       1,167,608               0               0               0       1,048,813       1,167,608
Construction............................         362,081         403,092               0               0               0         362,081         403,092
Drycleaning and Commercial Laundries....          56,623          63,037               0               0               0          56,623          63,037
Landscaping and Facilities Support......          97,542         108,590               0               0               0          97,542         108,590
Maintenance and Repair..................         250,133         278,465               0               0               0         250,133         278,465
Manufacturing...........................         168,477         187,560               0               0               0         168,477         187,560
Oil and Gas.............................          41,489          46,189               0               0               0          41,489          46,189
Postal and Delivery Services............          93,192         103,747               0               0               0          93,192         103,747
Recreation and Amusement................          96,716         107,670               0               0               0          96,716         107,670
Sanitation and Waste Removal............           7,882           8,774               0               0               0           7,882           8,774
Telecommunications......................          18,319          20,394               0               0               0          18,319          20,394
Temporary Help Services.................          23,160          25,783               0               0               0          23,160          25,783
Transportation..........................         264,703         294,685               0               0               0         264,703         294,685
Utilities...............................          37,716          41,988               0               0               0          37,716          41,988
Warehousing.............................          48,360          53,837               0               0               0          48,360          53,837
Non-Core................................       4,048,215       4,506,737               0               0               0       4,048,215       4,506,737
                                         ---------------------------------------------------------------------------------------------------------------
    Subtotal............................       6,839,737       7,614,442               0               0               0       6,839,737       7,614,442
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                     Review Monitoring Equipment User Manual--Indoor
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing......           5,992           6,671               0               0               0           5,992           6,671
Building Materials and Equipment                   3,096           3,447               0               0               0           3,096           3,447
 Suppliers..............................
Commercial Kitchens.....................          36,379          40,499               0               0               0          36,379          40,499
Construction............................          60,102          66,909               0               0               0          60,102          66,909
Drycleaning and Commercial Laundries....           3,115           3,467               0               0               0           3,115           3,467
Landscaping and Facilities Support......           5,921           6,592               0               0               0           5,921           6,592
Maintenance and Repair..................          13,758          15,317               0               0               0          13,758          15,317
Manufacturing...........................          29,769          33,141               0               0               0          29,769          33,141
Oil and Gas.............................           3,383           3,766               0               0               0           3,383           3,766
Postal and Delivery Services............           5,704           6,350               0               0               0           5,704           6,350
Recreation and Amusement................           4,495           5,004               0               0               0           4,495           5,004
Sanitation and Waste Removal............             446             496               0               0               0             446             496
Telecommunications......................           1,643           1,829               0               0               0           1,643           1,829
Temporary Help Services.................           1,309           1,458               0               0               0           1,309           1,458
Transportation..........................          16,201          18,036               0               0               0          16,201          18,036
Utilities...............................           3,579           3,984               0               0               0           3,579           3,984
Warehousing.............................           2,960           3,295               0               0               0           2,960           3,295
Non-Core................................         139,235         155,005               0               0               0         139,235         155,005
                                         ---------------------------------------------------------------------------------------------------------------
    Subtotal............................         337,086         375,266               0               0               0         337,086         375,266
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                          Total
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing......         124,854         138,996         550,921         572,954       6,560,724       7,236,500       7,272,674
Building Materials and Equipment                  60,550          67,408         257,367         267,659       2,841,664       3,159,581       3,176,732
 Suppliers..............................
Commercial Kitchens.....................       1,085,192       1,208,107       3,071,569       3,194,407      31,062,385      35,219,146      35,464,900
Construction............................         422,183         470,002       2,643,957       2,749,695      32,568,167      35,634,308      35,787,864
Drycleaning and Commercial Laundries....          59,738          66,504         254,700         264,886       2,780,229       3,094,667       3,111,620
Landscaping and Facilities Support......         103,463         115,182         434,682         452,065       5,777,946       6,316,091       6,345,193
Maintenance and Repair..................         263,892         293,782       1,148,890       1,194,837      12,823,176      14,235,958      14,311,794
Manufacturing...........................         198,246         220,701         954,170         992,329      10,851,040      12,003,456      12,064,070
Oil and Gas.............................          44,873          49,955         257,938         268,253       3,366,958       3,669,768       3,685,166
Postal and Delivery Services............          98,895         110,097         462,306         480,795       5,380,302       5,941,504       5,971,194
Recreation and Amusement................         101,211         112,674         366,868         381,540       4,381,662       4,849,741       4,875,876
Sanitation and Waste Removal............           8,327           9,270          35,510          36,930         426,225         470,062         472,425
Telecommunications......................          19,962          22,223         138,118         143,641       1,580,416       1,738,495       1,746,280
Temporary Help Services.................          24,469          27,241         103,518         107,658       1,188,114       1,316,102       1,323,013
Transportation..........................         280,904         312,721       1,445,964       1,503,791      15,742,625      17,469,493      17,559,137

[[Page 70863]]

 
Utilities...............................          41,295          45,972         258,014         268,332       3,506,013       3,805,322       3,820,318
Warehousing.............................          51,319          57,132         238,172         247,697       2,664,809       2,954,301       2,969,638
Non-Core................................       4,187,450       4,661,742      18,728,628      19,477,626     224,330,788     247,246,865     248,470,156
                                         ---------------------------------------------------------------------------------------------------------------
    Total...............................       7,176,823       7,989,707      31,351,291      32,605,096     367,833,244     406,361,358     408,428,047
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source: OSHA estimate.
Note: Due to rounding, figures in the columns and rows may not sum to the totals shown.

D. Requirements at or Above the Initial Heat Trigger
I. Drinking Water
    All affected establishments would be required to provide 
sufficiently cool water to their affected employees. In order to meet 
this requirement, OSHA assumes that establishments would purchase one 
40-quart cooler for every 40 employees. These establishments would also 
purchase reusable water bottles for each affected employee.
II. Break Area(s) at Outdoor Work Sites
    All affected establishments would also have to provide break areas 
for affected employees. At establishments with outdoor work sites, OSHA 
assumes that each establishment would purchase a twelve-by-twelve-foot 
tent as a means of providing artificial shade. OSHA assumes that 
establishments would incur this cost one time.
III. Break Area(s) and Work Area(s) at Indoor Work Sites
    Establishments with indoor work sites would purchase one industrial 
pedestal fan and one dehumidifier that provide sufficient air movement 
and humidity control in break areas for every 10 employees. 
Establishments with indoor work sites would also have to purchase these 
same control measures for work areas for every 10 employees. However, 
OSHA does not capture a cost for dehumidifiers for establishments with 
indoor work sites in the four least humid States in the U.S. (Arizona, 
Nevada, New Mexico, and Utah).
IV. Acclimatization
    Both new and returning employees would undergo acclimatization 
during their first week of work when the initial heat trigger is met or 
exceeded during that first week. To calculate acclimatization costs, 
OSHA multiplied the unit costs for acclimatization shown in section 
VIII.C.IV.D.IV., by the number of new employees and by the number of 
returning employees. OSHA calculates the number of new employees using 
BLS' Job Openings and Labor Turnover Survey (JOLTS) (BLS JOLTS, 2024). 
OSHA used the JOLTS hire rates from June through August for 2023 by 
sector to represent the percentage of employees that are new and join 
their respective employers when the initial heat trigger is met or 
exceeded. OSHA lacks data that would allow further refinement of this 
estimate. Calculating the number of new employees based on those hired 
in June through August may not accurately represent the universe of 
employees who will need acclimatization. This assumption may 
underestimate the number of newly hired employees in areas where the 
heat season is longer but might overestimate the number in areas where 
the weather is cooler for more of the year. OSHA also heard from Small 
Entity Representatives during the SBAR Panel process that they 
purposefully avoid hiring new employees during times when temperatures 
are high in order to avoid the difficulties and costs of 
acclimatization. Therefore, again, using the JOLTS data for this 
timeframe may overstate the number of employees who will need 
acclimatization. OSHA also applies this assumption to employees working 
indoors in settings without adequate climate control but, as discussed 
above in section VIII.C.II.C., acknowledges that this assumption that 
outdoor heat translates to indoor heat may over- or understate the 
temperatures indoors. The agency welcomes comment on this estimate as 
well as data that would allow this parameter to be better estimated.
    To calculate the number of returning employees, OSHA assumed that 
two percent of all employees not newly hired would qualify as returning 
employees (i.e., those returning to work from an absence of more than 
14 days during a time when the initial or high heat trigger are met). 
OSHA welcomes comment on this estimate and information or data sources 
that might better allow the agency to identify employees returning from 
absences of more than 14 days. Next, OSHA multiplied the two percent by 
one minus the annual hire rate according to the JOLTS data by sector. 
OSHA then multiplied this product by the ratio of the summer hire rate 
to annual hire rate to arrive at the percentage of employees returning 
to work when the initial heat trigger is met or exceeded during their 
first week back.
V. Rest Breaks if Needed
    To calculate the cost for if-needed rest breaks when the initial 
heat trigger is met or exceeded, OSHA first calculated the number of 
rest breaks that affected employees would be expected to take annually. 
OSHA used the number of work hours in a given State for each work shift 
type (daytime, evening, and overnight) that met or exceeded the initial 
heat trigger but did not meet or exceed the high heat trigger. The 
estimated number of hours was then normalized to 8-hour work shift 
equivalents by dividing the number of hours meeting or exceeding the 
initial heat trigger (but not meeting the high heat trigger) by 
eight.\78\ OSHA then multiplied these 8-hour work shift equivalents, 
the number of affected employees, and the corresponding unit costs for 
rest breaks for indoor and outdoor employees as shown in section 
VIII.C.IV.D.V. to determine total costs for rest breaks at the initial 
heat trigger.
---------------------------------------------------------------------------

    \78\ By assuming full, 8-hour work shifts at or above the heat 
trigger(s), this methodology may overstate the number of breaks 
employers need to provide since there may be some days where the 
heat triggers are met or exceeded but for shorter periods of time. 
For example, if the high heat trigger is met or exceeded for less 
than two hours, the requirement to provide a scheduled rest break 
would not be triggered. Additionally, employees exposed to heat at 
or above the initial heat trigger for shorter periods of time are 
likely to need fewer if-needed rest breaks. A scheduled lunch break 
in the middle of the day may also be sufficient to satisfy the break 
requirement on days when the high heat trigger is met for only a 
portion of the day. OSHA welcomes comment on this methodology and 
recommendations on alternative approaches.
---------------------------------------------------------------------------

    As discussed in section VIII.C.IV.D.V. and detailed further in 
appendix A at the end of this section, OSHA estimates that under the 
proposed standard, the reduction in time spent on pacing (i.e., the 
increase in worker efficiency) will partially offset the added cost of 
time

[[Page 70864]]

spent on if-needed rest breaks when the initial heat trigger is met or 
exceeded for employees in Group 1 (i.e., currently noncompliant with 
if-needed rest breaks as well as scheduled rest breaks), by 20 percent 
and 23.33 percent for outdoor and indoor employees, respectively. 
Combining this estimated partial offset of the unit cost of if-needed 
rest breaks as required by the proposed standard with data on the 
industry-level and/or State-level number of in-scope employees 
(discussed in Section VIII.B., Profile of Affected Industries), 
baseline non-compliance rates (discussed in section VIII.C.II.A.), and 
State-level exposure to heat at or above the initial heat trigger 
(discussed in section VIII.C.II.C.), OSHA estimates that approximately 
21.78 percent of the total cost of compliance with if-needed rest 
breaks when the initial heat trigger is met or exceeded (approximately 
$0.0875 billion out of $0.402 billion) could be offset by avoided labor 
productivity losses due to pacing (i.e., avoided losses in worker 
efficiency).
VI. Effective Communication
    Employers would also be required to effectively communicate with 
affected employees when the initial heat trigger is met or exceeded. 
OSHA first calculated the number of times a designated person would 
have to perform this duty by estimating the number of hours annually 
that meet or exceed the initial heat trigger for each State. OSHA then 
normalized these estimates to reflect 8-hour work shift equivalents. 
These 8-hour work shift equivalents are then multiplied by the number 
of affected employees and the unit costs as shown in Section 
VIII.C.IV.D.VI., Effective Communication, of 15 seconds every two hours 
of both a designated person's and at-risk employee's time.
    Table VIII.C.24. shows the annualized one-time, annual, and total 
annualized costs for each of these requirements by industry category 
and region, discounted (2 percent over a 10-year period) and 
undiscounted.

                                     Table VIII.C.24--Total Costs--Requirements at or Above the Initial Heat Trigger
                                                                         [2023$]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                           One-time annualized                                                  Total annualized
                 Industry category                 ----------------------------------      Annual        Annual cost   ---------------------------------
                                                           0%               2%                             savings             0%               2%
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                   Coolers with Spigot
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing:
    Alaskan.......................................              $15              $16               $0               $0              $15              $16
    Central.......................................            1,822            2,028                0                0            1,822            2,028
    Eastern.......................................            1,294            1,441                0                0            1,294            1,441
    Pacific.......................................               13               15                0                0               13               15
    Southern......................................            1,941            2,161                0                0            1,941            2,161
    Western.......................................              447              498                0                0              447              498
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................            5,532            6,158                0                0            5,532            6,158
Building Materials and Equipment Suppliers:
    Alaskan.......................................               23               25                0                0               23               25
    Central.......................................            2,115            2,355                0                0            2,115            2,355
    Eastern.......................................            2,627            2,925                0                0            2,627            2,925
    Pacific.......................................               41               45                0                0               41               45
    Southern......................................            2,456            2,734                0                0            2,456            2,734
    Western.......................................            1,497            1,667                0                0            1,497            1,667
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................            8,759            9,751                0                0            8,759            9,751
Commercial Kitchens:
    Alaskan.......................................              125              140                0                0              125              140
    Central.......................................           14,789           16,465                0                0           14,789           16,465
    Eastern.......................................           22,011           24,504                0                0           22,011           24,504
    Pacific.......................................              476              530                0                0              476              530
    Southern......................................           19,755           21,993                0                0           19,755           21,993
    Western.......................................           12,343           13,741                0                0           12,343           13,741
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0           77,372                0                0           69,500           77,372
Construction:
    Alaskan.......................................              235              262                0                0              235              262
    Central.......................................           17,355           19,321                0                0           17,355           19,321
    Eastern.......................................           25,296           28,161                0                0           25,296           28,161
    Pacific.......................................              499              556                0                0              499              556
    Southern......................................           65,874           73,335                0                0           65,874           73,335
    Western.......................................           18,599           20,706                0                0           18,599           20,706
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................          127,859          142,341                0                0          127,859          142,341
Drycleaning and Commercial Laundries:
    Alaskan.......................................                2                3                0                0                2                3
    Central.......................................              277              309                0                0              277              309
    Eastern.......................................              508              566                0                0              508              566
    Pacific.......................................               11               12                0                0               11               12
    Southern......................................              401              446                0                0              401              446
    Western.......................................              249              277                0                0              249              277
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................            1,448            1,612                0                0            1,448            1,612
Landscaping and Facilities Support:
    Alaskan.......................................               87               96                0                0               87               96
    Central.......................................            5,475            6,095                0                0            5,475            6,095
    Eastern.......................................            8,862            9,865                0                0            8,862            9,865
    Pacific.......................................              171              191                0                0              171              191
    Southern......................................            7,341            8,173                0                0            7,341            8,173
    Western.......................................           20,404           22,716                0                0           20,404           22,716
                                                   -----------------------------------------------------------------------------------------------------

[[Page 70865]]

 
        Subtotal..................................           42,340           47,136                0                0           42,340           47,136
Maintenance and Repair:
    Alaskan.......................................               26               29                0                0               26               29
    Central.......................................            2,866            3,190                0                0            2,866            3,190
    Eastern.......................................            3,702            4,121                0                0            3,702            4,121
    Pacific.......................................               45               50                0                0               45               50
    Southern......................................            3,449            3,839                0                0            3,449            3,839
    Western.......................................            2,148            2,391                0                0            2,148            2,391
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................           12,235           13,621                0                0           12,235           13,621
Manufacturing:
    Alaskan.......................................               70               78                0                0               70               78
    Central.......................................           22,988           25,592                0                0           22,988           25,592
    Eastern.......................................           21,278           23,688                0                0           21,278           23,688
    Pacific.......................................               65               72                0                0               65               72
    Southern......................................           17,040           18,970                0                0           17,040           18,970
    Western.......................................           11,035           12,284                0                0           11,035           12,284
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................           72,475           80,684                0                0           72,475           80,684
Oil and Gas:
    Alaskan.......................................               76               85                0                0               76               85
    Central.......................................              554              617                0                0              554              617
    Eastern.......................................              362              403                0                0              362              403
    Southern......................................            3,468            3,861                0                0            3,468            3,861
    Western.......................................              725              807                0                0              725              807
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................            5,185            5,772                0                0            5,185            5,772
Postal and Delivery Services:
    Alaskan.......................................                5                6                0                0                5                6
    Central.......................................              974            1,084                0                0              974            1,084
    Eastern.......................................            1,556            1,732                0                0            1,556            1,732
    Pacific.......................................               16               17                0                0               16               17
    Southern......................................            1,104            1,229                0                0            1,104            1,229
    Western.......................................              776              864                0                0              776              864
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................            4,431            4,933                0                0            4,431            4,933
Recreation and Amusement:
    Alaskan.......................................               23               26                0                0               23               26
    Central.......................................            2,358            2,625                0                0            2,358            2,625
    Eastern.......................................            3,928            4,373                0                0            3,928            4,373
    Pacific.......................................               51               57                0                0               51               57
    Southern......................................            3,076            3,425                0                0            3,076            3,425
    Western.......................................            2,314            2,576                0                0            2,314            2,576
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................           11,750           13,081                0                0           11,750           13,081
Sanitation and Waste Removal:
    Alaskan.......................................               14               15                0                0               14               15
    Central.......................................              427              476                0                0              427              476
    Eastern.......................................              723              805                0                0              723              805
    Pacific.......................................               13               14                0                0               13               14
    Southern......................................              577              642                0                0              577              642
    Western.......................................              347              386                0                0              347              386
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................            2,101            2,339                0                0            2,101            2,339
Telecommunications:
    Alaskan.......................................               12               14                0                0               12               14
    Central.......................................              641              713                0                0              641              713
    Eastern.......................................              973            1,083                0                0              973            1,083
    Pacific.......................................               12               13                0                0               12               13
    Southern......................................              884              984                0                0              884              984
    Western.......................................              453              505                0                0              453              505
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................            2,975            3,312                0                0            2,975            3,312
Temporary Help Services:
    Alaskan.......................................                7                8                0                0                7                8
    Central.......................................            6,812            7,583                0                0            6,812            7,583
    Eastern.......................................            8,706            9,692                0                0            8,706            9,692
    Pacific.......................................              204              228                0                0              204              228
    Southern......................................           14,093           15,689                0                0           14,093           15,689
    Western.......................................            7,054            7,853                0                0            7,054            7,853
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................           36,877           41,053                0                0           36,877           41,053
Transportation:
    Alaskan.......................................               99              110                0                0               99              110
    Central.......................................            4,282            4,768                0                0            4,282            4,768
    Eastern.......................................            4,364            4,859                0                0            4,364            4,859
    Pacific.......................................              147              163                0                0              147              163
    Southern......................................            5,809            6,467                0                0            5,809            6,467
    Western.......................................            1,895            2,110                0                0            1,895            2,110
                                                   -----------------------------------------------------------------------------------------------------

[[Page 70866]]

 
        Subtotal..................................           16,597           18,477                0                0           16,597           18,477
Utilities:
    Alaskan.......................................               16               18                0                0               16               18
    Central.......................................            1,233            1,373                0                0            1,233            1,373
    Eastern.......................................            1,725            1,921                0                0            1,725            1,921
    Pacific.......................................                7                7                0                0                7                7
    Southern......................................            1,477            1,644                0                0            1,477            1,644
    Western.......................................              683              760                0                0              683              760
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................            5,141            5,723                0                0            5,141            5,723
Warehousing:
    Alaskan.......................................                3                3                0                0                3                3
    Central.......................................            1,489            1,658                0                0            1,489            1,658
    Eastern.......................................            2,181            2,428                0                0            2,181            2,428
    Pacific.......................................                9               10                0                0                9               10
    Southern......................................            1,846            2,055                0                0            1,846            2,055
    Western.......................................            1,211            1,348                0                0            1,211            1,348
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................            6,738            7,502                0                0            6,738            7,502
Non-Core:
    Alaskan.......................................              837              932                0                0              837              932
    Central.......................................           68,086           75,798                0                0           68,086           75,798
    Eastern.......................................          112,634          125,392                0                0          112,634          125,392
    Pacific.......................................            1,673            1,862                0                0            1,673            1,862
    Southern......................................           62,705           69,807                0                0           62,705           69,807
    Western.......................................           61,070           67,987                0                0           61,070           67,987
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................          307,005          341,778                0                0          307,005          341,778
Total Costs for Coolers with Spigot:
    Alaskan.......................................            1,676            1,866                0                0            1,676            1,866
    Central.......................................          154,543          172,047                0                0          154,543          172,047
    Eastern.......................................          222,731          247,959                0                0          222,731          247,959
    Pacific.......................................            3,453            3,844                0                0            3,453            3,844
    Southern......................................          213,294          237,453                0                0          213,294          237,453
    Western.......................................          143,251          159,476                0                0          143,251          159,476
                                                   -----------------------------------------------------------------------------------------------------
        Total.....................................          738,948          822,646                0                0          738,948          822,646
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                  Reusable Water Bottle
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing:
    Alaskan.......................................                4                5                0                0                4                5
    Central.......................................              537              598                0                0              537              598
    Eastern.......................................              382              425                0                0              382              425
    Pacific.......................................                4                4                0                0                4                4
    Southern......................................              573              637                0                0              573              637
    Western.......................................              132              147                0                0              132              147
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................            1,632            1,817                0                0            1,632            1,817
Building Materials and Equipment Suppliers:
    Alaskan.......................................                7                7                0                0                7                7
    Central.......................................              624              695                0                0              624              695
    Eastern.......................................              775              863                0                0              775              863
    Pacific.......................................               12               13                0                0               12               13
    Southern......................................              725              807                0                0              725              807
    Western.......................................              442              492                0                0              442              492
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................            2,584            2,877                0                0            2,584            2,877
Commercial Kitchens:
    Alaskan.......................................               37               41                0                0               37               41
    Central.......................................            4,363            4,858                0                0            4,363            4,858
    Eastern.......................................            6,494            7,229                0                0            6,494            7,229
    Pacific.......................................              141              156                0                0              141              156
    Southern......................................            5,829            6,489                0                0            5,829            6,489
    Western.......................................            3,642            4,054                0                0            3,642            4,054
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................           20,505           22,828                0                0           20,505           22,828
Construction:
    Alaskan.......................................               69               77                0                0               69               77
    Central.......................................            5,120            5,700                0                0            5,120            5,700
    Eastern.......................................            7,463            8,309                0                0            7,463            8,309
    Pacific.......................................              147              164                0                0              147              164
    Southern......................................           19,435           21,636                0                0           19,435           21,636
    Western.......................................            5,487            6,109                0                0            5,487            6,109
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................           37,723           41,996                0                0           37,723           41,996
Drycleaning and Commercial Laundries:
    Alaskan.......................................                1                1                0                0                1                1
    Central.......................................               82               91                0                0               82               91

[[Page 70867]]

 
    Eastern.......................................              150              167                0                0              150              167
    Pacific.......................................                3                4                0                0                3                4
    Southern......................................              118              132                0                0              118              132
    Western.......................................               73               82                0                0               73               82
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................              427              476                0                0              427              476
Landscaping and Facilities Support:
    Alaskan.......................................               26               28                0                0               26               28
    Central.......................................            1,615            1,798                0                0            1,615            1,798
    Eastern.......................................            2,615            2,911                0                0            2,615            2,911
    Pacific.......................................               51               56                0                0               51               56
    Southern......................................            2,166            2,411                0                0            2,166            2,411
    Western.......................................            6,020            6,702                0                0            6,020            6,702
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................           12,492           13,907                0                0           12,492           13,907
Maintenance and Repair:
    Alaskan.......................................                8                8                0                0                8                8
    Central.......................................              846              941                0                0              846              941
    Eastern.......................................            1,092            1,216                0                0            1,092            1,216
    Pacific.......................................               13               15                0                0               13               15
    Southern......................................            1,017            1,133                0                0            1,017            1,133
    Western.......................................              634              705                0                0              634              705
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................            3,610            4,019                0                0            3,610            4,019
Manufacturing:
    Alaskan.......................................               21               23                0                0               21               23
    Central.......................................            6,782            7,550                0                0            6,782            7,550
    Eastern.......................................            6,278            6,989                0                0            6,278            6,989
    Pacific.......................................               19               21                0                0               19               21
    Southern......................................            5,027            5,597                0                0            5,027            5,597
    Western.......................................            3,256            3,624                0                0            3,256            3,624
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................           21,383           23,805                0                0           21,383           23,805
Oil and Gas:
    Alaskan.......................................               22               25                0                0               22               25
    Central.......................................              163              182                0                0              163              182
    Eastern.......................................              107              119                0                0              107              119
    Southern......................................            1,023            1,139                0                0            1,023            1,139
    Western.......................................              214              238                0                0              214              238
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................            1,530            1,703                0                0            1,530            1,703
Postal and Delivery Services:
    Alaskan.......................................                2                2                0                0                2                2
    Central.......................................              287              320                0                0              287              320
    Eastern.......................................              459              511                0                0              459              511
    Pacific.......................................                5                5                0                0                5                5
    Southern......................................              326              363                0                0              326              363
    Western.......................................              229              255                0                0              229              255
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................            1,307            1,455                0                0            1,307            1,455
Recreation and Amusement:
    Alaskan.......................................                7                8                0                0                7                8
    Central.......................................              696              774                0                0              696              774
    Eastern.......................................            1,159            1,290                0                0            1,159            1,290
    Pacific.......................................               15               17                0                0               15               17
    Southern......................................              908            1,010                0                0              908            1,010
    Western.......................................              683              760                0                0              683              760
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................            3,467            3,859                0                0            3,467            3,859
Sanitation and Waste Removal:
    Alaskan.......................................                4                5                0                0                4                5
    Central.......................................              126              140                0                0              126              140
    Eastern.......................................              213              238                0                0              213              238
    Pacific.......................................                4                4                0                0                4                4
    Southern......................................              170              189                0                0              170              189
    Western.......................................              102              114                0                0              102              114
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................              620              690                0                0              620              690
Telecommunications:
    Alaskan.......................................                4                4                0                0                4                4
    Central.......................................              189              210                0                0              189              210
    Eastern.......................................              287              320                0                0              287              320
    Pacific.......................................                3                4                0                0                3                4
    Southern......................................              261              290                0                0              261              290
    Western.......................................              134              149                0                0              134              149
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................              878              977                0                0              878              977
Temporary Help Services:
    Alaskan.......................................                2                2                0                0                2                2

[[Page 70868]]

 
    Central.......................................            2,010            2,237                0                0            2,010            2,237
    Eastern.......................................            2,568            2,859                0                0            2,568            2,859
    Pacific.......................................               60               67                0                0               60               67
    Southern......................................            4,158            4,629                0                0            4,158            4,629
    Western.......................................            2,081            2,317                0                0            2,081            2,317
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................           10,880           12,112                0                0           10,880           12,112
Transportation:
    Alaskan.......................................               29               33                0                0               29               33
    Central.......................................            1,263            1,407                0                0            1,263            1,407
    Eastern.......................................            1,288            1,434                0                0            1,288            1,434
    Pacific.......................................               43               48                0                0               43               48
    Southern......................................            1,714            1,908                0                0            1,714            1,908
    Western.......................................              559              622                0                0              559              622
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................            4,897            5,451                0                0            4,897            5,451
Utilities:
    Alaskan.......................................                5                5                0                0                5                5
    Central.......................................              364              405                0                0              364              405
    Eastern.......................................              509              567                0                0              509              567
    Pacific.......................................                2                2                0                0                2                2
    Southern......................................              436              485                0                0              436              485
    Western.......................................              202              224                0                0              202              224
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................            1,517            1,689                0                0            1,517            1,689
Warehousing:
    Alaskan.......................................                1                1                0                0                1                1
    Central.......................................              439              489                0                0              439              489
    Eastern.......................................              643              716                0                0              643              716
    Pacific.......................................                3                3                0                0                3                3
    Southern......................................              545              606                0                0              545              606
    Western.......................................              357              398                0                0              357              398
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................            1,988            2,213                0                0            1,988            2,213
Non-Core:
    Alaskan.......................................              247              275                0                0              247              275
    Central.......................................           20,088           22,363                0                0           20,088           22,363
    Eastern.......................................           33,231           36,995                0                0           33,231           36,995
    Pacific.......................................              494              549                0                0              494              549
    Southern......................................           18,500           20,596                0                0           18,500           20,596
    Western.......................................           18,018           20,059                0                0           18,018           20,059
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................           90,578          100,837                0                0           90,578          100,837
Total Costs for Reusable Water Bottle:
    Alaskan.......................................              494              550                0                0              494              550
    Central.......................................           45,596           50,760                0                0           45,596           50,760
    Eastern.......................................           65,714           73,157                0                0           65,714           73,157
    Pacific.......................................            1,019            1,134                0                0            1,019            1,134
    Southern......................................           62,930           70,057                0                0           62,930           70,057
    Western.......................................           42,264           47,051                0                0           42,264           47,051
                                                   -----------------------------------------------------------------------------------------------------
        Total.....................................          218,017          242,711                0                0          218,017          242,711
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                         Outdoor Break Area Engineering Control
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing:
    Alaskan.......................................            2,139            2,381                0                0            2,139            2,381
    Central.......................................          148,614          165,447                0                0          148,614          165,447
    Eastern.......................................           82,148           91,452                0                0           82,148           91,452
    Pacific.......................................            1,094            1,218                0                0            1,094            1,218
    Southern......................................          141,834          157,899                0                0          141,834          157,899
    Western.......................................           34,464           38,367                0                0           34,464           38,367
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................          410,292          456,764                0                0          410,292          456,764
Building Materials and Equipment Suppliers:
    Alaskan.......................................              113              126                0                0              113              126
    Central.......................................            8,748            9,738                0                0            8,748            9,738
    Eastern.......................................           12,576           14,001                0                0           12,576           14,001
    Pacific.......................................              209              233                0                0              209              233
    Southern......................................           11,796           13,133                0                0           11,796           13,133
    Western.......................................            7,958            8,859                0                0            7,958            8,859
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................           41,401           46,090                0                0           41,401           46,090
Commercial Kitchens:
    Alaskan.......................................              319              355                0                0              319              355
    Central.......................................           24,910           27,731                0                0           24,910           27,731
    Eastern.......................................           39,778           44,284                0                0           39,778           44,284
    Pacific.......................................              766              853                0                0              766              853
    Southern......................................           28,473           31,698                0                0           28,473           31,698

[[Page 70869]]

 
    Western.......................................           22,781           25,361                0                0           22,781           25,361
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................          117,026          130,281                0                0          117,026          130,281
Construction:
    Alaskan.......................................            4,131            4,599                0                0            4,131            4,599
    Central.......................................          265,524          295,599                0                0          265,524          295,599
    Eastern.......................................          385,284          428,923                0                0          385,284          428,923
    Pacific.......................................            5,698            6,343                0                0            5,698            6,343
    Southern......................................          278,496          310,040                0                0          278,496          310,040
    Western.......................................          116,376          129,557                0                0          116,376          129,557
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................        1,055,509        1,175,062                0                0        1,055,509        1,175,062
Drycleaning and Commercial Laundries:
    Alaskan.......................................               28               31                0                0               28               31
    Central.......................................            3,440            3,830                0                0            3,440            3,830
    Eastern.......................................            8,838            9,839                0                0            8,838            9,839
    Pacific.......................................               70               77                0                0               70               77
    Southern......................................            5,216            5,806                0                0            5,216            5,806
    Western.......................................            3,579            3,984                0                0            3,579            3,984
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................           21,170           23,567                0                0           21,170           23,567
Landscaping and Facilities Support:
    Alaskan.......................................              500              556                0                0              500              556
    Central.......................................           53,460           59,515                0                0           53,460           59,515
    Eastern.......................................           86,844           96,680                0                0           86,844           96,680
    Pacific.......................................            1,227            1,366                0                0            1,227            1,366
    Southern......................................           60,819           67,707                0                0           60,819           67,707
    Western.......................................           49,560           55,173                0                0           49,560           55,173
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................          252,409          280,998                0                0          252,409          280,998
Maintenance and Repair:
    Alaskan.......................................              553              616                0                0              553              616
    Central.......................................           56,502           62,902                0                0           56,502           62,902
    Eastern.......................................           75,259           83,783                0                0           75,259           83,783
    Pacific.......................................              903            1,005                0                0              903            1,005
    Southern......................................           60,866           67,760                0                0           60,866           67,760
    Western.......................................           44,596           49,647                0                0           44,596           49,647
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................          238,677          265,711                0                0          238,677          265,711
Manufacturing:
    Alaskan.......................................              109              121                0                0              109              121
    Central.......................................           13,706           15,258                0                0           13,706           15,258
    Eastern.......................................           16,157           17,987                0                0           16,157           17,987
    Pacific.......................................              138              153                0                0              138              153
    Southern......................................           12,473           13,886                0                0           12,473           13,886
    Western.......................................           10,469           11,655                0                0           10,469           11,655
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................           53,053           59,062                0                0           53,053           59,062
Oil and Gas:
    Alaskan.......................................              371              413                0                0              371              413
    Central.......................................           14,887           16,573                0                0           14,887           16,573
    Eastern.......................................            7,969            8,871                0                0            7,969            8,871
    Southern......................................           54,268           60,415                0                0           54,268           60,415
    Western.......................................            7,404            8,243                0                0            7,404            8,243
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................           84,899           94,515                0                0           84,899           94,515
Postal and Delivery Services:
    Alaskan.......................................              660              735                0                0              660              735
    Central.......................................           28,109           31,293                0                0           28,109           31,293
    Eastern.......................................           35,229           39,219                0                0           35,229           39,219
    Pacific.......................................              367              409                0                0              367              409
    Southern......................................           25,444           28,325                0                0           25,444           28,325
    Western.......................................           14,637           16,294                0                0           14,637           16,294
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................          104,446          116,276                0                0          104,446          116,276
Recreation and Amusement:
    Alaskan.......................................              911            1,014                0                0              911            1,014
    Central.......................................           35,982           40,057                0                0           35,982           40,057
    Eastern.......................................           53,826           59,922                0                0           53,826           59,922
    Pacific.......................................              666              741                0                0              666              741
    Southern......................................           35,056           39,027                0                0           35,056           39,027
    Western.......................................           27,649           30,780                0                0           27,649           30,780
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................          154,089          171,542                0                0          154,089          171,542
Sanitation and Waste Removal:
    Alaskan.......................................               75               83                0                0               75               83
    Central.......................................            2,469            2,749                0                0            2,469            2,749
    Eastern.......................................            3,594            4,001                0                0            3,594            4,001
    Pacific.......................................               56               62                0                0               56               62

[[Page 70870]]

 
    Southern......................................            2,609            2,905                0                0            2,609            2,905
    Western.......................................            1,605            1,787                0                0            1,605            1,787
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................           10,408           11,587                0                0           10,408           11,587
Telecommunications:
    Alaskan.......................................               96              107                0                0               96              107
    Central.......................................            5,824            6,483                0                0            5,824            6,483
    Eastern.......................................            7,971            8,874                0                0            7,971            8,874
    Pacific.......................................               87               97                0                0               87               97
    Southern......................................            7,002            7,795                0                0            7,002            7,795
    Western.......................................            4,503            5,013                0                0            4,503            5,013
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................           25,482           28,368                0                0           25,482           28,368
Temporary Help Services:
    Alaskan.......................................               16               18                0                0               16               18
    Central.......................................            3,116            3,469                0                0            3,116            3,469
    Eastern.......................................            4,390            4,888                0                0            4,390            4,888
    Pacific.......................................               42               47                0                0               42               47
    Southern......................................            3,728            4,150                0                0            3,728            4,150
    Western.......................................            2,499            2,782                0                0            2,499            2,782
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................           13,791           15,353                0                0           13,791           15,353
Transportation:
    Alaskan.......................................            2,163            2,408                0                0            2,163            2,408
    Central.......................................          130,909          145,737                0                0          130,909          145,737
    Eastern.......................................          116,569          129,772                0                0          116,569          129,772
    Pacific.......................................            1,448            1,612                0                0            1,448            1,612
    Southern......................................          118,579          132,010                0                0          118,579          132,010
    Western.......................................           40,067           44,605                0                0           40,067           44,605
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................          409,735          456,144                0                0          409,735          456,144
Utilities:
    Alaskan.......................................              333              370                0                0              333              370
    Central.......................................           14,246           15,860                0                0           14,246           15,860
    Eastern.......................................           17,850           19,872                0                0           17,850           19,872
    Pacific.......................................              121              135                0                0              121              135
    Southern......................................           19,989           22,253                0                0           19,989           22,253
    Western.......................................            9,235           10,281                0                0            9,235           10,281
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................           61,775           68,772                0                0           61,775           68,772
Warehousing:
    Alaskan.......................................               37               41                0                0               37               41
    Central.......................................            5,364            5,971                0                0            5,364            5,971
    Eastern.......................................            6,782            7,550                0                0            6,782            7,550
    Pacific.......................................               86               96                0                0               86               96
    Southern......................................            6,658            7,412                0                0            6,658            7,412
    Western.......................................            4,713            5,247                0                0            4,713            5,247
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................           23,639           26,317                0                0           23,639           26,317
Non-Core:
    Alaskan.......................................           10,666           11,875                0                0           10,666           11,875
    Central.......................................          771,392          858,764                0                0          771,392          858,764
    Eastern.......................................        1,203,522        1,339,839                0                0        1,203,522        1,339,839
    Pacific.......................................           19,907           22,161                0                0           19,907           22,161
    Southern......................................          938,300        1,044,577                0                0          938,300        1,044,577
    Western.......................................          697,582          776,594                0                0          697,582          776,594
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................        3,641,370        4,053,811                0                0        3,641,370        4,053,811
Total Costs for Outdoor Break Area Engineering
 Control:
    Alaskan.......................................           23,219           25,849                0                0           23,219           25,849
    Central.......................................        1,587,201        1,766,975                0                0        1,587,201        1,766,975
    Eastern.......................................        2,164,586        2,409,758                0                0        2,164,586        2,409,758
    Pacific.......................................           32,884           36,608                0                0           32,884           36,608
    Southern......................................        1,811,607        2,016,799                0                0        1,811,607        2,016,799
    Western.......................................        1,099,676        1,224,231                0                0        1,099,676        1,224,231
                                                   -----------------------------------------------------------------------------------------------------
        Total.....................................        6,719,171        7,480,220                0                0        6,719,171        7,480,220
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                      Air Movement
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing:
    Alaskan.......................................              329              366                0                0              329              366
    Central.......................................          108,158          120,408                0                0          108,158          120,408
    Eastern.......................................           60,978           67,885                0                0           60,978           67,885
    Pacific.......................................              639              711                0                0              639              711
    Southern......................................           90,405          100,644                0                0           90,405          100,644
    Western.......................................          154,877          172,419                0                0          154,877          172,419
                                                   -----------------------------------------------------------------------------------------------------

[[Page 70871]]

 
        Subtotal..................................          415,385          462,433                0                0          415,385          462,433
Building Materials and Equipment Suppliers:
    Alaskan.......................................            1,021            1,137                0                0            1,021            1,137
    Central.......................................           95,087          105,857                0                0           95,087          105,857
    Eastern.......................................          117,705          131,037                0                0          117,705          131,037
    Pacific.......................................            1,817            2,022                0                0            1,817            2,022
    Southern......................................          108,302          120,569                0                0          108,302          120,569
    Western.......................................           76,760           85,455                0                0           76,760           85,455
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................          400,693          446,078                0                0          400,693          446,078
Commercial Kitchens:
    Alaskan.......................................            7,767            8,647                0                0            7,767            8,647
    Central.......................................          920,349        1,024,593                0                0          920,349        1,024,593
    Eastern.......................................        1,369,741        1,524,885                0                0        1,369,741        1,524,885
    Pacific.......................................           29,672           33,033                0                0           29,672           33,033
    Southern......................................        1,231,959        1,371,497                0                0        1,231,959        1,371,497
    Western.......................................          855,252          952,122                0                0          855,252          952,122
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................        4,414,740        4,914,777                0                0        4,414,740        4,914,777
Construction:
    Alaskan.......................................            6,033            6,716                0                0            6,033            6,716
    Central.......................................          434,847          484,100                0                0          434,847          484,100
    Eastern.......................................          636,158          708,213                0                0          636,158          708,213
    Pacific.......................................           12,280           13,670                0                0           12,280           13,670
    Southern......................................          613,504          682,993                0                0          613,504          682,993
    Western.......................................          440,836          490,768                0                0          440,836          490,768
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................        2,143,659        2,386,461                0                0        2,143,659        2,386,461
Drycleaning and Commercial Laundries:
    Alaskan.......................................              120              133                0                0              120              133
    Central.......................................           14,557           16,206                0                0           14,557           16,206
    Eastern.......................................           26,699           29,723                0                0           26,699           29,723
    Pacific.......................................              581              647                0                0              581              647
    Southern......................................           21,042           23,425                0                0           21,042           23,425
    Western.......................................           14,307           15,927                0                0           14,307           15,927
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................           77,306           86,062                0                0           77,306           86,062
Landscaping and Facilities Support:
    Alaskan.......................................            2,383            2,653                0                0            2,383            2,653
    Central.......................................          125,165          139,342                0                0          125,165          139,342
    Eastern.......................................          202,660          225,615                0                0          202,660          225,615
    Pacific.......................................            3,766            4,193                0                0            3,766            4,193
    Southern......................................          168,079          187,117                0                0          168,079          187,117
    Western.......................................          113,917          126,820                0                0          113,917          126,820
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................          615,970          685,738                0                0          615,970          685,738
Maintenance and Repair:
    Alaskan.......................................            1,009            1,124                0                0            1,009            1,124
    Central.......................................          112,682          125,445                0                0          112,682          125,445
    Eastern.......................................          145,140          161,579                0                0          145,140          161,579
    Pacific.......................................            1,762            1,961                0                0            1,762            1,961
    Southern......................................          136,568          152,036                0                0          136,568          152,036
    Western.......................................           94,222          104,894                0                0           94,222          104,894
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................          491,382          547,039                0                0          491,382          547,039
Manufacturing:
    Alaskan.......................................            3,604            4,012                0                0            3,604            4,012
    Central.......................................        1,299,063        1,446,201                0                0        1,299,063        1,446,201
    Eastern.......................................        1,193,136        1,328,277                0                0        1,193,136        1,328,277
    Pacific.......................................            3,459            3,851                0                0            3,459            3,851
    Southern......................................          941,420        1,048,050                0                0          941,420        1,048,050
    Western.......................................          556,173          619,168                0                0          556,173          619,168
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................        3,996,855        4,449,560                0                0        3,996,855        4,449,560
Oil and Gas:
    Alaskan.......................................            1,954            2,175                0                0            1,954            2,175
    Central.......................................           14,641           16,299                0                0           14,641           16,299
    Eastern.......................................            9,558           10,641                0                0            9,558           10,641
    Southern......................................           90,159          100,371                0                0           90,159          100,371
    Western.......................................            9,362           10,422                0                0            9,362           10,422
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................          125,674          139,908                0                0          125,674          139,908
Postal and Delivery Services:
    Alaskan.......................................              195              217                0                0              195              217
    Central.......................................           38,356           42,701                0                0           38,356           42,701
    Eastern.......................................           61,466           68,428                0                0           61,466           68,428
    Pacific.......................................              601              670                0                0              601              670
    Southern......................................           43,628           48,570                0                0           43,628           48,570
    Western.......................................           34,742           38,677                0                0           34,742           38,677
                                                   -----------------------------------------------------------------------------------------------------

[[Page 70872]]

 
        Subtotal..................................          178,989          199,262                0                0          178,989          199,262
Recreation and Amusement:
    Alaskan.......................................              711              792                0                0              711              792
    Central.......................................           72,605           80,828                0                0           72,605           80,828
    Eastern.......................................          120,964          134,665                0                0          120,964          134,665
    Pacific.......................................            1,579            1,757                0                0            1,579            1,757
    Southern......................................           94,989          105,748                0                0           94,989          105,748
    Western.......................................           80,440           89,551                0                0           80,440           89,551
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................          371,287          413,341                0                0          371,287          413,341
Sanitation and Waste Removal:
    Alaskan.......................................              402              448                0                0              402              448
    Central.......................................           14,210           15,819                0                0           14,210           15,819
    Eastern.......................................           23,287           25,925                0                0           23,287           25,925
    Pacific.......................................              405              451                0                0              405              451
    Southern......................................           18,720           20,840                0                0           18,720           20,840
    Western.......................................           13,505           15,035                0                0           13,505           15,035
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................           70,529           78,518                0                0           70,529           78,518
Telecommunications:
    Alaskan.......................................              484              539                0                0              484              539
    Central.......................................           25,066           27,905                0                0           25,066           27,905
    Eastern.......................................           38,069           42,381                0                0           38,069           42,381
    Pacific.......................................              454              505                0                0              454              505
    Southern......................................           34,579           38,496                0                0           34,579           38,496
    Western.......................................           21,013           23,393                0                0           21,013           23,393
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................          119,665          133,218                0                0          119,665          133,218
Temporary Help Services:
    Alaskan.......................................              339              377                0                0              339              377
    Central.......................................          318,045          354,068                0                0          318,045          354,068
    Eastern.......................................          406,486          452,527                0                0          406,486          452,527
    Pacific.......................................            9,548           10,629                0                0            9,548           10,629
    Southern......................................          658,041          732,574                0                0          658,041          732,574
    Western.......................................          343,674          382,600                0                0          343,674          382,600
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................        1,736,132        1,932,776                0                0        1,736,132        1,932,776
Transportation:
    Alaskan.......................................            2,987            3,325                0                0            2,987            3,325
    Central.......................................          134,943          150,227                0                0          134,943          150,227
    Eastern.......................................          138,796          154,516                0                0          138,796          154,516
    Pacific.......................................            4,572            5,089                0                0            4,572            5,089
    Southern......................................          183,350          204,117                0                0          183,350          204,117
    Western.......................................          101,601          113,109                0                0          101,601          113,109
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................          566,248          630,384                0                0          566,248          630,384
Utilities:
    Alaskan.......................................              499              556                0                0              499              556
    Central.......................................           37,661           41,927                0                0           37,661           41,927
    Eastern.......................................           52,688           58,655                0                0           52,688           58,655
    Pacific.......................................              206              229                0                0              206              229
    Southern......................................           45,122           50,233                0                0           45,122           50,233
    Western.......................................           22,843           25,430                0                0           22,843           25,430
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................          159,019          177,031                0                0          159,019          177,031
Warehousing:
    Alaskan.......................................              125              139                0                0              125              139
    Central.......................................           73,616           81,954                0                0           73,616           81,954
    Eastern.......................................          107,817          120,029                0                0          107,817          120,029
    Pacific.......................................              446              497                0                0              446              497
    Southern......................................           91,232          101,565                0                0           91,232          101,565
    Western.......................................           65,675           73,114                0                0           65,675           73,114
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................          338,911          377,297                0                0          338,911          377,297
Non-Core:
    Alaskan.......................................           53,752           59,840                0                0           53,752           59,840
    Central.......................................        4,747,729        5,285,482                0                0        4,747,729        5,285,482
    Eastern.......................................        7,725,828        8,600,896                0                0        7,725,828        8,600,896
    Pacific.......................................          112,841          125,622                0                0          112,841          125,622
    Southern......................................        4,614,342        5,136,987                0                0        4,614,342        5,136,987
    Western.......................................        4,639,061        5,164,506                0                0        4,639,061        5,164,506
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................       21,893,554       24,373,334                0                0       21,893,554       24,373,334
Total Costs for Air Movement:
    Alaskan.......................................           83,713           93,195                0                0           83,713           93,195
    Central.......................................        8,586,779        9,559,363                0                0        8,586,779        9,559,363
    Eastern.......................................       12,437,176       13,845,877                0                0       12,437,176       13,845,877
    Pacific.......................................          184,628          205,540                0                0          184,628          205,540
    Southern......................................        9,185,441       10,225,833                0                0        9,185,441       10,225,833

[[Page 70873]]

 
    Western.......................................        7,638,260        8,503,410                0                0        7,638,260        8,503,410
                                                   -----------------------------------------------------------------------------------------------------
        Total.....................................       38,115,998       42,433,217                0                0       38,115,998       42,433,217
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                    Humidity Control
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing:
    Alaskan.......................................               95              106                0                0               95              106
    Central.......................................           31,400           34,957                0                0           31,400           34,957
    Eastern.......................................           17,703           19,708                0                0           17,703           19,708
    Pacific.......................................              185              206                0                0              185              206
    Southern......................................           25,671           28,578                0                0           25,671           28,578
    Western.......................................           42,556           47,376                0                0           42,556           47,376
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................          117,611          130,932                0                0          117,611          130,932
Building Materials and Equipment Suppliers:
    Alaskan.......................................              297              330                0                0              297              330
    Central.......................................           27,606           30,732                0                0           27,606           30,732
    Eastern.......................................           34,172           38,042                0                0           34,172           38,042
    Pacific.......................................              527              587                0                0              527              587
    Southern......................................           30,778           34,264                0                0           30,778           34,264
    Western.......................................           18,585           20,690                0                0           18,585           20,690
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................          111,964          124,646                0                0          111,964          124,646
Commercial Kitchens:
    Alaskan.......................................            2,255            2,510                0                0            2,255            2,510
    Central.......................................          267,194          297,458                0                0          267,194          297,458
    Eastern.......................................          397,660          442,701                0                0          397,660          442,701
    Pacific.......................................            8,614            9,590                0                0            8,614            9,590
    Southern......................................          349,840          389,465                0                0          349,840          389,465
    Western.......................................          198,024          220,453                0                0          198,024          220,453
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................        1,223,587        1,362,177                0                0        1,223,587        1,362,177
Construction:
    Alaskan.......................................            1,751            1,950                0                0            1,751            1,950
    Central.......................................          126,244          140,543                0                0          126,244          140,543
    Eastern.......................................          184,688          205,607                0                0          184,688          205,607
    Pacific.......................................            3,565            3,969                0                0            3,565            3,969
    Southern......................................          174,434          194,191                0                0          174,434          194,191
    Western.......................................           99,311          110,559                0                0           99,311          110,559
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................          589,993          656,819                0                0          589,993          656,819
Drycleaning and Commercial Laundries:
    Alaskan.......................................               35               39                0                0               35               39
    Central.......................................            4,226            4,705                0                0            4,226            4,705
    Eastern.......................................            7,751            8,629                0                0            7,751            8,629
    Pacific.......................................              169              188                0                0              169              188
    Southern......................................            5,975            6,651                0                0            5,975            6,651
    Western.......................................            3,210            3,573                0                0            3,210            3,573
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................           21,365           23,785                0                0           21,365           23,785
Landscaping and Facilities Support:
    Alaskan.......................................              692              770                0                0              692              770
    Central.......................................           36,338           40,453                0                0           36,338           40,453
    Eastern.......................................           58,836           65,500                0                0           58,836           65,500
    Pacific.......................................            1,093            1,217                0                0            1,093            1,217
    Southern......................................           48,013           53,451                0                0           48,013           53,451
    Western.......................................           25,082           27,923                0                0           25,082           27,923
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................          170,054          189,315                0                0          170,054          189,315
Maintenance and Repair:
    Alaskan.......................................              293              326                0                0              293              326
    Central.......................................           32,714           36,419                0                0           32,714           36,419
    Eastern.......................................           42,137           46,909                0                0           42,137           46,909
    Pacific.......................................              511              569                0                0              511              569
    Southern......................................           38,727           43,113                0                0           38,727           43,113
    Western.......................................           21,788           24,255                0                0           21,788           24,255
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................          136,169          151,592                0                0          136,169          151,592
Manufacturing:
    Alaskan.......................................            1,046            1,165                0                0            1,046            1,165
    Central.......................................          377,141          419,858                0                0          377,141          419,858
    Eastern.......................................          346,389          385,622                0                0          346,389          385,622
    Pacific.......................................            1,004            1,118                0                0            1,004            1,118
    Southern......................................          271,764          302,545                0                0          271,764          302,545
    Western.......................................          136,507          151,968                0                0          136,507          151,968
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................        1,133,851        1,262,277                0                0        1,133,851        1,262,277
Oil and Gas:

[[Page 70874]]

 
    Alaskan.......................................              567              631                0                0              567              631
    Central.......................................            4,250            4,732                0                0            4,250            4,732
    Eastern.......................................            2,775            3,089                0                0            2,775            3,089
    Southern......................................           24,984           27,813                0                0           24,984           27,813
    Western.......................................            2,148            2,392                0                0            2,148            2,392
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................           34,724           38,657                0                0           34,724           38,657
Postal and Delivery Services:
    Alaskan.......................................               56               63                0                0               56               63
    Central.......................................           11,136           12,397                0                0           11,136           12,397
    Eastern.......................................           17,845           19,866                0                0           17,845           19,866
    Pacific.......................................              175              194                0                0              175              194
    Southern......................................           12,429           13,836                0                0           12,429           13,836
    Western.......................................            8,172            9,097                0                0            8,172            9,097
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................           49,812           55,453                0                0           49,812           55,453
Recreation and Amusement:
    Alaskan.......................................              207              230                0                0              207              230
    Central.......................................           21,078           23,466                0                0           21,078           23,466
    Eastern.......................................           35,118           39,096                0                0           35,118           39,096
    Pacific.......................................              458              510                0                0              458              510
    Southern......................................           27,043           30,106                0                0           27,043           30,106
    Western.......................................           19,011           21,164                0                0           19,011           21,164
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................          102,915          114,572                0                0          102,915          114,572
Sanitation and Waste Removal:
    Alaskan.......................................              117              130                0                0              117              130
    Central.......................................            4,125            4,593                0                0            4,125            4,593
    Eastern.......................................            6,761            7,527                0                0            6,761            7,527
    Pacific.......................................              118              131                0                0              118              131
    Southern......................................            5,329            5,933                0                0            5,329            5,933
    Western.......................................            3,191            3,553                0                0            3,191            3,553
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................           19,641           21,866                0                0           19,641           21,866
Telecommunications:
    Alaskan.......................................              141              157                0                0              141              157
    Central.......................................            7,277            8,101                0                0            7,277            8,101
    Eastern.......................................           11,052           12,304                0                0           11,052           12,304
    Pacific.......................................              132              147                0                0              132              147
    Southern......................................            9,825           10,938                0                0            9,825           10,938
    Western.......................................            4,802            5,346                0                0            4,802            5,346
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................           33,228           36,991                0                0           33,228           36,991
Temporary Help Services:
    Alaskan.......................................               98              110                0                0               98              110
    Central.......................................           92,334          102,792                0                0           92,334          102,792
    Eastern.......................................          118,010          131,377                0                0          118,010          131,377
    Pacific.......................................            2,772            3,086                0                0            2,772            3,086
    Southern......................................          190,450          212,021                0                0          190,450          212,021
    Western.......................................           78,264           87,129                0                0           78,264           87,129
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................          481,928          536,514                0                0          481,928          536,514
Transportation:
    Alaskan.......................................              867              965                0                0              867              965
    Central.......................................           39,176           43,614                0                0           39,176           43,614
    Eastern.......................................           40,295           44,859                0                0           40,295           44,859
    Pacific.......................................            1,327            1,478                0                0            1,327            1,478
    Southern......................................           52,599           58,556                0                0           52,599           58,556
    Western.......................................           22,771           25,350                0                0           22,771           25,350
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................          157,035          174,822                0                0          157,035          174,822
Utilities:
    Alaskan.......................................              145              161                0                0              145              161
    Central.......................................           10,934           12,172                0                0           10,934           12,172
    Eastern.......................................           15,296           17,029                0                0           15,296           17,029
    Pacific.......................................               60               67                0                0               60               67
    Southern......................................           12,788           14,236                0                0           12,788           14,236
    Western.......................................            5,328            5,931                0                0            5,328            5,931
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................           44,550           49,596                0                0           44,550           49,596
Warehousing:
    Alaskan.......................................               36               40                0                0               36               40
    Central.......................................           21,372           23,793                0                0           21,372           23,793
    Eastern.......................................           31,301           34,846                0                0           31,301           34,846
    Pacific.......................................              130              144                0                0              130              144
    Southern......................................           26,358           29,343                0                0           26,358           29,343
    Western.......................................           15,033           16,735                0                0           15,033           16,735
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................           94,230          104,902                0                0           94,230          104,902

[[Page 70875]]

 
Non-Core:
    Alaskan.......................................           15,605           17,373                0                0           15,605           17,373
    Central.......................................        1,378,350        1,534,470                0                0        1,378,350        1,534,470
    Eastern.......................................        2,242,945        2,496,993                0                0        2,242,945        2,496,993
    Pacific.......................................           32,760           36,470                0                0           32,760           36,470
    Southern......................................        1,298,373        1,445,433                0                0        1,298,373        1,445,433
    Western.......................................        1,074,393        1,196,084                0                0        1,074,393        1,196,084
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................        6,042,426        6,726,823                0                0        6,042,426        6,726,823
Total Costs for Humidity Control:
    Alaskan.......................................           24,304           27,056                0                0           24,304           27,056
    Central.......................................        2,492,895        2,775,253                0                0        2,492,895        2,775,253
    Eastern.......................................        3,610,734        4,019,704                0                0        3,610,734        4,019,704
    Pacific.......................................           53,601           59,672                0                0           53,601           59,672
    Southern......................................        2,605,377        2,900,476                0                0        2,605,377        2,900,476
    Western.......................................        1,778,174        1,979,579                0                0        1,778,174        1,979,579
                                                   -----------------------------------------------------------------------------------------------------
        Total.....................................       10,565,084       11,761,741                0                0       10,565,084       11,761,741
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                     New Employee Acclimatization--Designated Person
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0           22,683                0           22,683           22,683
    Eastern.......................................                0                0           14,046                0           14,046           14,046
    Pacific.......................................                0                0              658                0              658              658
    Southern......................................                0                0           34,594                0           34,594           34,594
    Western.......................................                0                0           10,637                0           10,637           10,637
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0           82,618                0           82,618           82,618
Building Materials and Equipment Suppliers:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0            8,839                0            8,839            8,839
    Eastern.......................................                0                0           10,086                0           10,086           10,086
    Pacific.......................................                0                0              756                0              756              756
    Southern......................................                0                0           17,336                0           17,336           17,336
    Western.......................................                0                0            7,440                0            7,440            7,440
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0           44,458                0           44,458           44,458
Commercial Kitchens:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0           66,528                0           66,528           66,528
    Eastern.......................................                0                0           93,907                0           93,907           93,907
    Pacific.......................................                0                0            9,308                0            9,308            9,308
    Southern......................................                0                0          159,557                0          159,557          159,557
    Western.......................................                0                0           66,267                0           66,267           66,267
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0          395,566                0          395,566          395,566
Construction:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0          129,541                0          129,541          129,541
    Eastern.......................................                0                0          177,518                0          177,518          177,518
    Pacific.......................................                0                0           16,312                0           16,312           16,312
    Southern......................................                0                0          294,027                0          294,027          294,027
    Western.......................................                0                0           66,918                0           66,918           66,918
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0          684,317                0          684,317          684,317
Drycleaning and Commercial Laundries:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0            1,288                0            1,288            1,288
    Eastern.......................................                0                0            2,184                0            2,184            2,184
    Pacific.......................................                0                0              228                0              228              228
    Southern......................................                0                0            3,057                0            3,057            3,057
    Western.......................................                0                0            1,351                0            1,351            1,351
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0            8,108                0            8,108            8,108
Landscaping and Facilities Support:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0           23,521                0           23,521           23,521
    Eastern.......................................                0                0           35,839                0           35,839           35,839
    Pacific.......................................                0                0            3,250                0            3,250            3,250
    Southern......................................                0                0           52,232                0           52,232           52,232
    Western.......................................                0                0           28,306                0           28,306           28,306
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0          143,148                0          143,148          143,148
Maintenance and Repair:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0           13,304                0           13,304           13,304
    Eastern.......................................                0                0           16,305                0           16,305           16,305

[[Page 70876]]

 
    Pacific.......................................                0                0              931                0              931              931
    Southern......................................                0                0           26,401                0           26,401           26,401
    Western.......................................                0                0           11,705                0           11,705           11,705
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0           68,645                0           68,645           68,645
Manufacturing:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0           96,792                0           96,792           96,792
    Eastern.......................................                0                0           91,190                0           91,190           91,190
    Pacific.......................................                0                0            1,258                0            1,258            1,258
    Southern......................................                0                0          117,159                0          117,159          117,159
    Western.......................................                0                0           44,603                0           44,603           44,603
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0          351,003                0          351,003          351,003
Oil and Gas:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0            4,390                0            4,390            4,390
    Eastern.......................................                0                0            2,615                0            2,615            2,615
    Southern......................................                0                0           40,324                0           40,324           40,324
    Western.......................................                0                0            2,640                0            2,640            2,640
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0           49,968                0           49,968           49,968
Postal and Delivery Services:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0            5,530                0            5,530            5,530
    Eastern.......................................                0                0            8,245                0            8,245            8,245
    Pacific.......................................                0                0              390                0              390              390
    Southern......................................                0                0           10,789                0           10,789           10,789
    Western.......................................                0                0            5,187                0            5,187            5,187
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0           30,140                0           30,140           30,140
Recreation and Amusement:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0           15,389                0           15,389           15,389
    Eastern.......................................                0                0           24,238                0           24,238           24,238
    Pacific.......................................                0                0            1,474                0            1,474            1,474
    Southern......................................                0                0           39,175                0           39,175           39,175
    Western.......................................                0                0           18,246                0           18,246           18,246
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0           98,522                0           98,522           98,522
Sanitation and Waste Removal:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0            1,782                0            1,782            1,782
    Eastern.......................................                0                0            2,781                0            2,781            2,781
    Pacific.......................................                0                0              237                0              237              237
    Southern......................................                0                0            3,921                0            3,921            3,921
    Western.......................................                0                0            1,742                0            1,742            1,742
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0           10,462                0           10,462           10,462
Telecommunications:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0            3,528                0            3,528            3,528
    Eastern.......................................                0                0            4,889                0            4,889            4,889
    Pacific.......................................                0                0              274                0              274              274
    Southern......................................                0                0            7,485                0            7,485            7,485
    Western.......................................                0                0            2,908                0            2,908            2,908
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0           19,083                0           19,083           19,083
Temporary Help Services:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0           28,772                0           28,772           28,772
    Eastern.......................................                0                0           35,627                0           35,627           35,627
    Pacific.......................................                0                0            3,810                0            3,810            3,810
    Southern......................................                0                0          107,950                0          107,950          107,950
    Western.......................................                0                0           33,490                0           33,490           33,490
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0          209,649                0          209,649          209,649
Transportation:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0           24,480                0           24,480           24,480
    Eastern.......................................                0                0           23,617                0           23,617           23,617
    Pacific.......................................                0                0            3,687                0            3,687            3,687
    Southern......................................                0                0           55,722                0           55,722           55,722
    Western.......................................                0                0           13,832                0           13,832           13,832
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0          121,339                0          121,339          121,339
Utilities:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0            9,201                0            9,201            9,201

[[Page 70877]]

 
    Eastern.......................................                0                0           12,379                0           12,379           12,379
    Pacific.......................................                0                0              229                0              229              229
    Southern......................................                0                0           18,581                0           18,581           18,581
    Western.......................................                0                0            6,092                0            6,092            6,092
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0           46,483                0           46,483           46,483
Warehousing:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0            8,709                0            8,709            8,709
    Eastern.......................................                0                0           12,191                0           12,191           12,191
    Pacific.......................................                0                0              227                0              227              227
    Southern......................................                0                0           16,982                0           16,982           16,982
    Western.......................................                0                0            8,107                0            8,107            8,107
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0           46,217                0           46,217           46,217
Non-Core:
    Alaskan.......................................                0                0                2                0                2                2
    Central.......................................                0                0          525,443                0          525,443          525,443
    Eastern.......................................                0                0          818,290                0          818,290          818,290
    Pacific.......................................                0                0           56,311                0           56,311           56,311
    Southern......................................                0                0          902,582                0          902,582          902,582
    Western.......................................                0                0          549,837                0          549,837          549,837
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        2,852,465                0        2,852,465        2,852,465
Total Costs for New Employee Acclimatization--
 Designated Person:
    Alaskan.......................................                0                0                3                0                3                3
    Central.......................................                0                0          989,721                0          989,721          989,721
    Eastern.......................................                0                0        1,385,945                0        1,385,945        1,385,945
    Pacific.......................................                0                0           99,338                0           99,338           99,338
    Southern......................................                0                0        1,907,875                0        1,907,875        1,907,875
    Western.......................................                0                0          879,308                0          879,308          879,308
                                                   -----------------------------------------------------------------------------------------------------
        Total.....................................                0                0        5,262,190                0        5,262,190        5,262,190
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                  Returning Employee Acclimatization--Designated Person
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0              550                0              550              550
    Eastern.......................................                0                0              341                0              341              341
    Pacific.......................................                0                0               16                0               16               16
    Southern......................................                0                0              839                0              839              839
    Western.......................................                0                0              258                0              258              258
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0            2,003                0            2,003            2,003
Building Materials and Equipment Suppliers:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0              252                0              252              252
    Eastern.......................................                0                0              308                0              308              308
    Pacific.......................................                0                0               21                0               21               21
    Southern......................................                0                0              523                0              523              523
    Western.......................................                0                0              226                0              226              226
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0            1,329                0            1,329            1,329
Commercial Kitchens:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0              429                0              429              429
    Eastern.......................................                0                0              606                0              606              606
    Pacific.......................................                0                0               63                0               63               63
    Southern......................................                0                0              996                0              996              996
    Western.......................................                0                0              429                0              429              429
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0            2,524                0            2,524            2,524
Construction:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0            2,049                0            2,049            2,049
    Eastern.......................................                0                0            2,806                0            2,806            2,806
    Pacific.......................................                0                0              258                0              258              258
    Southern......................................                0                0            4,652                0            4,652            4,652
    Western.......................................                0                0            1,053                0            1,053            1,053
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0           10,819                0           10,819           10,819
Drycleaning and Commercial Laundries:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0               33                0               33               33
    Eastern.......................................                0                0               56                0               56               56
    Pacific.......................................                0                0                6                0                6                6
    Southern......................................                0                0               79                0               79               79

[[Page 70878]]

 
    Western.......................................                0                0               35                0               35               35
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0              209                0              209              209
Landscaping and Facilities Support:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0              779                0              779              779
    Eastern.......................................                0                0            1,186                0            1,186            1,186
    Pacific.......................................                0                0              107                0              107              107
    Southern......................................                0                0            1,731                0            1,731            1,731
    Western.......................................                0                0              946                0              946              946
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0            4,748                0            4,748            4,748
Maintenance and Repair:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0              343                0              343              343
    Eastern.......................................                0                0              420                0              420              420
    Pacific.......................................                0                0               24                0               24               24
    Southern......................................                0                0              680                0              680              680
    Western.......................................                0                0              302                0              302              302
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0            1,769                0            1,769            1,769
Manufacturing:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0            3,339                0            3,339            3,339
    Eastern.......................................                0                0            3,146                0            3,146            3,146
    Pacific.......................................                0                0               43                0               43               43
    Southern......................................                0                0            4,042                0            4,042            4,042
    Western.......................................                0                0            1,539                0            1,539            1,539
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0           12,108                0           12,108           12,108
Oil and Gas:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0              103                0              103              103
    Eastern.......................................                0                0               61                0               61               61
    Southern......................................                0                0              958                0              958              958
    Western.......................................                0                0               62                0               62               62
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0            1,184                0            1,184            1,184
Postal and Delivery Services:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0              102                0              102              102
    Eastern.......................................                0                0              152                0              152              152
    Pacific.......................................                0                0                7                0                7                7
    Southern......................................                0                0              199                0              199              199
    Western.......................................                0                0               96                0               96               96
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0              556                0              556              556
Recreation and Amusement:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0               68                0               68               68
    Eastern.......................................                0                0              108                0              108              108
    Pacific.......................................                0                0                7                0                7                7
    Southern......................................                0                0              174                0              174              174
    Western.......................................                0                0               81                0               81               81
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0              437                0              437              437
Sanitation and Waste Removal:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0               61                0               61               61
    Eastern.......................................                0                0               96                0               96               96
    Pacific.......................................                0                0                8                0                8                8
    Southern......................................                0                0              135                0              135              135
    Western.......................................                0                0               60                0               60               60
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0              359                0              359              359
Telecommunications:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0              167                0              167              167
    Eastern.......................................                0                0              231                0              231              231
    Pacific.......................................                0                0               13                0               13               13
    Southern......................................                0                0              354                0              354              354
    Western.......................................                0                0              138                0              138              138
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0              903                0              903              903
Temporary Help Services:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0              988                0              988              988
    Eastern.......................................                0                0            1,224                0            1,224            1,224
    Pacific.......................................                0                0              131                0              131              131

[[Page 70879]]

 
    Southern......................................                0                0            3,708                0            3,708            3,708
    Western.......................................                0                0            1,150                0            1,150            1,150
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0            7,201                0            7,201            7,201
Transportation:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0              452                0              452              452
    Eastern.......................................                0                0              436                0              436              436
    Pacific.......................................                0                0               68                0               68               68
    Southern......................................                0                0            1,029                0            1,029            1,029
    Western.......................................                0                0              255                0              255              255
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0            2,240                0            2,240            2,240
Utilities:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0              221                0              221              221
    Eastern.......................................                0                0              298                0              298              298
    Pacific.......................................                0                0                6                0                6                6
    Southern......................................                0                0              447                0              447              447
    Western.......................................                0                0              147                0              147              147
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0            1,118                0            1,118            1,118
Warehousing:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0              161                0              161              161
    Eastern.......................................                0                0              225                0              225              225
    Pacific.......................................                0                0                4                0                4                4
    Southern......................................                0                0              314                0              314              314
    Western.......................................                0                0              150                0              150              150
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0              853                0              853              853
Non-Core:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0           18,283                0           18,283           18,283
    Eastern.......................................                0                0           28,957                0           28,957           28,957
    Pacific.......................................                0                0            1,869                0            1,869            1,869
    Southern......................................                0                0           25,241                0           25,241           25,241
    Western.......................................                0                0           20,730                0           20,730           20,730
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0           95,080                0           95,080           95,080
Total Costs for Returning Employee
 Acclimatization--Designated Person:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0           28,381                0           28,381           28,381
    Eastern.......................................                0                0           40,657                0           40,657           40,657
    Pacific.......................................                0                0            2,651                0            2,651            2,651
    Southern......................................                0                0           46,100                0           46,100           46,100
    Western.......................................                0                0           27,656                0           27,656           27,656
                                                   -----------------------------------------------------------------------------------------------------
        Total.....................................                0                0          145,444                0          145,444          145,444
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                           New Indoor Employee Acclimatization
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0          193,345                0          193,345          193,345
    Eastern.......................................                0                0          118,157                0          118,157          118,157
    Pacific.......................................                0                0            5,594                0            5,594            5,594
    Southern......................................                0                0          292,499                0          292,499          292,499
    Western.......................................                0                0           90,313                0           90,313           90,313
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0          699,909                0          699,909          699,909
Building Materials and Equipment Suppliers:
    Alaskan.......................................                0                0                1                0                1                1
    Central.......................................                0                0          200,995                0          200,995          200,995
    Eastern.......................................                0                0          228,631                0          228,631          228,631
    Pacific.......................................                0                0           17,117                0           17,117           17,117
    Southern......................................                0                0          387,695                0          387,695          387,695
    Western.......................................                0                0          167,006                0          167,006          167,006
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        1,001,445                0        1,001,445        1,001,445
Commercial Kitchens:
    Alaskan.......................................                0                0                6                0                6                6
    Central.......................................                0                0        2,459,217                0        2,459,217        2,459,217
    Eastern.......................................                0                0        3,471,889                0        3,471,889        3,471,889
    Pacific.......................................                0                0          343,188                0          343,188          343,188
    Southern......................................                0                0        5,921,221                0        5,921,221        5,921,221
    Western.......................................                0                0        2,451,199                0        2,451,199        2,451,199
                                                   -----------------------------------------------------------------------------------------------------

[[Page 70880]]

 
        Subtotal..................................                0                0       14,646,720                0       14,646,720       14,646,720
Construction:
    Alaskan.......................................                0                0                7                0                7                7
    Central.......................................                0                0        1,828,198                0        1,828,198        1,828,198
    Eastern.......................................                0                0        2,533,833                0        2,533,833        2,533,833
    Pacific.......................................                0                0          222,954                0          222,954          222,954
    Southern......................................                0                0        4,123,445                0        4,123,445        4,123,445
    Western.......................................                0                0        1,027,254                0        1,027,254        1,027,254
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        9,735,691                0        9,735,691        9,735,691
Drycleaning and Commercial Laundries:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0           35,160                0           35,160           35,160
    Eastern.......................................                0                0           59,609                0           59,609           59,609
    Pacific.......................................                0                0            6,222                0            6,222            6,222
    Southern......................................                0                0           83,456                0           83,456           83,456
    Western.......................................                0                0           36,894                0           36,894           36,894
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0          221,342                0          221,342          221,342
Landscaping and Facilities Support:
    Alaskan.......................................                0                0                1                0                1                1
    Central.......................................                0                0          227,016                0          227,016          227,016
    Eastern.......................................                0                0          346,329                0          346,329          346,329
    Pacific.......................................                0                0           30,706                0           30,706           30,706
    Southern......................................                0                0          504,064                0          504,064          504,064
    Western.......................................                0                0          266,057                0          266,057          266,057
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        1,374,173                0        1,374,173        1,374,173
Maintenance and Repair:
    Alaskan.......................................                0                0                1                0                1                1
    Central.......................................                0                0          271,890                0          271,890          271,890
    Eastern.......................................                0                0          332,610                0          332,610          332,610
    Pacific.......................................                0                0           18,859                0           18,859           18,859
    Southern......................................                0                0          542,961                0          542,961          542,961
    Western.......................................                0                0          237,715                0          237,715          237,715
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        1,404,036                0        1,404,036        1,404,036
Manufacturing:
    Alaskan.......................................                0                0                2                0                2                2
    Central.......................................                0                0        2,361,334                0        2,361,334        2,361,334
    Eastern.......................................                0                0        2,209,292                0        2,209,292        2,209,292
    Pacific.......................................                0                0           29,010                0           29,010           29,010
    Southern......................................                0                0        2,797,246                0        2,797,246        2,797,246
    Western.......................................                0                0        1,073,345                0        1,073,345        1,073,345
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        8,470,228                0        8,470,228        8,470,228
Oil and Gas:
    Alaskan.......................................                0                0                2                0                2                2
    Central.......................................                0                0           53,570                0           53,570           53,570
    Eastern.......................................                0                0           31,858                0           31,858           31,858
    Southern......................................                0                0          486,559                0          486,559          486,559
    Western.......................................                0                0           31,794                0           31,794           31,794
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0          603,784                0          603,784          603,784
Postal and Delivery Services:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0           98,673                0           98,673           98,673
    Eastern.......................................                0                0          147,574                0          147,574          147,574
    Pacific.......................................                0                0            6,848                0            6,848            6,848
    Southern......................................                0                0          193,367                0          193,367          193,367
    Western.......................................                0                0           94,004                0           94,004           94,004
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0          540,465                0          540,465          540,465
Recreation and Amusement:
    Alaskan.......................................                0                0                1                0                1                1
    Central.......................................                0                0          211,899                0          211,899          211,899
    Eastern.......................................                0                0          333,853                0          333,853          333,853
    Pacific.......................................                0                0           20,233                0           20,233           20,233
    Southern......................................                0                0          540,964                0          540,964          540,964
    Western.......................................                0                0          252,184                0          252,184          252,184
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        1,359,134                0        1,359,134        1,359,134
Sanitation and Waste Removal:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0           24,083                0           24,083           24,083
    Eastern.......................................                0                0           36,457                0           36,457           36,457
    Pacific.......................................                0                0            3,068                0            3,068            3,068
    Southern......................................                0                0           51,809                0           51,809           51,809
    Western.......................................                0                0           23,188                0           23,188           23,188
                                                   -----------------------------------------------------------------------------------------------------

[[Page 70881]]

 
        Subtotal..................................                0                0          138,605                0          138,605          138,605
Telecommunications:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0           73,774                0           73,774           73,774
    Eastern.......................................                0                0          102,236                0          102,236          102,236
    Pacific.......................................                0                0            5,728                0            5,728            5,728
    Southern......................................                0                0          156,530                0          156,530          156,530
    Western.......................................                0                0           60,813                0           60,813           60,813
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0          399,081                0          399,081          399,081
Temporary Help Services:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0          545,638                0          545,638          545,638
    Eastern.......................................                0                0          675,623                0          675,623          675,623
    Pacific.......................................                0                0           72,247                0           72,247           72,247
    Southern......................................                0                0        2,047,160                0        2,047,160        2,047,160
    Western.......................................                0                0          635,109                0          635,109          635,109
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        3,975,776                0        3,975,776        3,975,776
Transportation:
    Alaskan.......................................                0                0                2                0                2                2
    Central.......................................                0                0          349,275                0          349,275          349,275
    Eastern.......................................                0                0          340,221                0          340,221          340,221
    Pacific.......................................                0                0           52,048                0           52,048           52,048
    Southern......................................                0                0          797,648                0          797,648          797,648
    Western.......................................                0                0          198,447                0          198,447          198,447
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        1,737,639                0        1,737,639        1,737,639
Utilities:
    Alaskan.......................................                0                0                1                0                1                1
    Central.......................................                0                0          186,352                0          186,352          186,352
    Eastern.......................................                0                0          250,671                0          250,671          250,671
    Pacific.......................................                0                0            4,646                0            4,646            4,646
    Southern......................................                0                0          376,360                0          376,360          376,360
    Western.......................................                0                0          123,487                0          123,487          123,487
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0          941,515                0          941,515          941,515
Warehousing:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0          194,963                0          194,963          194,963
    Eastern.......................................                0                0          272,889                0          272,889          272,889
    Pacific.......................................                0                0            5,083                0            5,083            5,083
    Southern......................................                0                0          380,156                0          380,156          380,156
    Western.......................................                0                0          181,486                0          181,486          181,486
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        1,034,577                0        1,034,577        1,034,577
Non-Core:
    Alaskan.......................................                0                0               32                0               32               32
    Central.......................................                0                0       11,211,606                0       11,211,606       11,211,606
    Eastern.......................................                0                0       17,218,995                0       17,218,995       17,218,995
    Pacific.......................................                0                0        1,136,938                0        1,136,938        1,136,938
    Southern......................................                0                0       19,641,718                0       19,641,718       19,641,718
    Western.......................................                0                0       11,524,405                0       11,524,405       11,524,405
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0       60,733,695                0       60,733,695       60,733,695
Total Costs for New Indoor Employee
 Acclimatization:
    Alaskan.......................................                0                0               56                0               56               56
    Central.......................................                0                0       20,526,989                0       20,526,989       20,526,989
    Eastern.......................................                0                0       28,710,726                0       28,710,726       28,710,726
    Pacific.......................................                0                0        1,980,487                0        1,980,487        1,980,487
    Southern......................................                0                0       39,324,858                0       39,324,858       39,324,858
    Western.......................................                0                0       18,474,699                0       18,474,699       18,474,699
                                                   -----------------------------------------------------------------------------------------------------
        Total.....................................                0                0      109,017,815                0      109,017,815      109,017,815
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                          New Outdoor Employee Acclimatization
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing:
    Alaskan.......................................                0                0                1                0                1                1
    Central.......................................                0                0          555,498                0          555,498          555,498
    Eastern.......................................                0                0          345,783                0          345,783          345,783
    Pacific.......................................                0                0           16,128                0           16,128           16,128
    Southern......................................                0                0          849,910                0          849,910          849,910
    Western.......................................                0                0          260,886                0          260,886          260,886
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        2,028,206                0        2,028,206        2,028,206
Building Materials and Equipment Suppliers:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0          116,270                0          116,270          116,270

[[Page 70882]]

 
    Eastern.......................................                0                0          133,667                0          133,667          133,667
    Pacific.......................................                0                0           10,037                0           10,037           10,037
    Southern......................................                0                0          236,477                0          236,477          236,477
    Western.......................................                0                0          100,700                0          100,700          100,700
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0          597,153                0          597,153          597,153
Commercial Kitchens:
    Alaskan.......................................                0                0                1                0                1                1
    Central.......................................                0                0          237,085                0          237,085          237,085
    Eastern.......................................                0                0          333,855                0          333,855          333,855
    Pacific.......................................                0                0           32,738                0           32,738           32,738
    Southern......................................                0                0          556,756                0          556,756          556,756
    Western.......................................                0                0          233,410                0          233,410          233,410
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        1,393,844                0        1,393,844        1,393,844
Construction:
    Alaskan.......................................                0                0               12                0               12               12
    Central.......................................                0                0        3,377,743                0        3,377,743        3,377,743
    Eastern.......................................                0                0        4,623,309                0        4,623,309        4,623,309
    Pacific.......................................                0                0          427,668                0          427,668          427,668
    Southern......................................                0                0        7,682,911                0        7,682,911        7,682,911
    Western.......................................                0                0        1,736,798                0        1,736,798        1,736,798
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0       17,848,441                0       17,848,441       17,848,441
Drycleaning and Commercial Laundries:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0           11,476                0           11,476           11,476
    Eastern.......................................                0                0           19,456                0           19,456           19,456
    Pacific.......................................                0                0            2,031                0            2,031            2,031
    Southern......................................                0                0           27,240                0           27,240           27,240
    Western.......................................                0                0           12,042                0           12,042           12,042
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0           72,246                0           72,246           72,246
Landscaping and Facilities Support:
    Alaskan.......................................                0                0                2                0                2                2
    Central.......................................                0                0          507,726                0          507,726          507,726
    Eastern.......................................                0                0          773,553                0          773,553          773,553
    Pacific.......................................                0                0           71,873                0           71,873           71,873
    Southern......................................                0                0        1,125,493                0        1,125,493        1,125,493
    Western.......................................                0                0          610,538                0          610,538          610,538
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        3,089,185                0        3,089,185        3,089,185
Maintenance and Repair:
    Alaskan.......................................                0                0                1                0                1                1
    Central.......................................                0                0          222,942                0          222,942          222,942
    Eastern.......................................                0                0          273,945                0          273,945          273,945
    Pacific.......................................                0                0           15,795                0           15,795           15,795
    Southern......................................                0                0          438,537                0          438,537          438,537
    Western.......................................                0                0          197,862                0          197,862          197,862
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        1,149,081                0        1,149,081        1,149,081
Manufacturing:
    Alaskan.......................................                0                0                1                0                1                1
    Central.......................................                0                0          529,914                0          529,914          529,914
    Eastern.......................................                0                0          516,810                0          516,810          516,810
    Pacific.......................................                0                0            8,812                0            8,812            8,812
    Southern......................................                0                0          711,140                0          711,140          711,140
    Western.......................................                0                0          261,112                0          261,112          261,112
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        2,027,789                0        2,027,789        2,027,789
Oil and Gas:
    Alaskan.......................................                0                0                4                0                4                4
    Central.......................................                0                0           95,998                0           95,998           95,998
    Eastern.......................................                0                0           57,257                0           57,257           57,257
    Southern......................................                0                0          890,293                0          890,293          890,293
    Western.......................................                0                0           58,298                0           58,298           58,298
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        1,101,849                0        1,101,849        1,101,849
Postal and Delivery Services:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0           80,470                0           80,470           80,470
    Eastern.......................................                0                0          119,456                0          119,456          119,456
    Pacific.......................................                0                0            5,817                0            5,817            5,817
    Southern......................................                0                0          156,028                0          156,028          156,028
    Western.......................................                0                0           73,827                0           73,827           73,827
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0          435,598                0          435,598          435,598
Recreation and Amusement:
    Alaskan.......................................                0                0                1                0                1                1

[[Page 70883]]

 
    Central.......................................                0                0          288,790                0          288,790          288,790
    Eastern.......................................                0                0          455,142                0          455,142          455,142
    Pacific.......................................                0                0           27,480                0           27,480           27,480
    Southern......................................                0                0          733,313                0          733,313          733,313
    Western.......................................                0                0          342,375                0          342,375          342,375
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        1,847,101                0        1,847,101        1,847,101
Sanitation and Waste Removal:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0           28,326                0           28,326           28,326
    Eastern.......................................                0                0           45,492                0           45,492           45,492
    Pacific.......................................                0                0            3,910                0            3,910            3,910
    Southern......................................                0                0           63,700                0           63,700           63,700
    Western.......................................                0                0           28,103                0           28,103           28,103
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0          169,531                0          169,531          169,531
Telecommunications:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0           61,192                0           61,192           61,192
    Eastern.......................................                0                0           84,800                0           84,800           84,800
    Pacific.......................................                0                0            4,751                0            4,751            4,751
    Southern......................................                0                0          129,833                0          129,833          129,833
    Western.......................................                0                0           50,442                0           50,442           50,442
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0          331,018                0          331,018          331,018
Temporary Help Services:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0          278,149                0          278,149          278,149
    Eastern.......................................                0                0          344,411                0          344,411          344,411
    Pacific.......................................                0                0           36,829                0           36,829           36,829
    Southern......................................                0                0        1,043,577                0        1,043,577        1,043,577
    Western.......................................                0                0          323,758                0          323,758          323,758
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        2,026,725                0        2,026,725        2,026,725
Transportation:
    Alaskan.......................................                0                0                3                0                3                3
    Central.......................................                0                0          456,381                0          456,381          456,381
    Eastern.......................................                0                0          436,573                0          436,573          436,573
    Pacific.......................................                0                0           69,357                0           69,357           69,357
    Southern......................................                0                0        1,035,820                0        1,035,820        1,035,820
    Western.......................................                0                0          256,606                0          256,606          256,606
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        2,254,740                0        2,254,740        2,254,740
Utilities:
    Alaskan.......................................                0                0                1                0                1                1
    Central.......................................                0                0          257,850                0          257,850          257,850
    Eastern.......................................                0                0          346,941                0          346,941          346,941
    Pacific.......................................                0                0            6,406                0            6,406            6,406
    Southern......................................                0                0          520,692                0          520,692          520,692
    Western.......................................                0                0          170,610                0          170,610          170,610
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        1,302,500                0        1,302,500        1,302,500
Warehousing:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0           81,507                0           81,507           81,507
    Eastern.......................................                0                0          114,085                0          114,085          114,085
    Pacific.......................................                0                0            2,125                0            2,125            2,125
    Southern......................................                0                0          158,929                0          158,929          158,929
    Western.......................................                0                0           75,873                0           75,873           75,873
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0          432,519                0          432,519          432,519
Non-Core:
    Alaskan.......................................                0                0               30                0               30               30
    Central.......................................                0                0        8,624,746                0        8,624,746        8,624,746
    Eastern.......................................                0                0       13,666,774                0       13,666,774       13,666,774
    Pacific.......................................                0                0          981,519                0          981,519          981,519
    Southern......................................                0                0       13,733,045                0       13,733,045       13,733,045
    Western.......................................                0                0        9,513,647                0        9,513,647        9,513,647
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0       46,519,760                0       46,519,760       46,519,760
Total Costs for New Outdoor Employee
 Acclimatization:
    Alaskan.......................................                0                0               56                0               56               56
    Central.......................................                0                0       15,812,062                0       15,812,062       15,812,062
    Eastern.......................................                0                0       22,691,309                0       22,691,309       22,691,309
    Pacific.......................................                0                0        1,723,276                0        1,723,276        1,723,276
    Southern......................................                0                0       30,093,696                0       30,093,696       30,093,696
    Western.......................................                0                0       14,306,888                0       14,306,888       14,306,888
                                                   -----------------------------------------------------------------------------------------------------

[[Page 70884]]

 
        Total.....................................                0                0       84,627,286                0       84,627,286       84,627,286
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                        Returning Indoor Employee Acclimatization
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0            4,688                0            4,688            4,688
    Eastern.......................................                0                0            2,865                0            2,865            2,865
    Pacific.......................................                0                0              136                0              136              136
    Southern......................................                0                0            7,092                0            7,092            7,092
    Western.......................................                0                0            6,503                0            6,503            6,503
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0           21,284                0           21,284           21,284
Building Materials and Equipment Suppliers:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0            5,665                0            5,665            5,665
    Eastern.......................................                0                0            6,911                0            6,911            6,911
    Pacific.......................................                0                0              461                0              461              461
    Southern......................................                0                0           11,569                0           11,569           11,569
    Western.......................................                0                0            5,026                0            5,026            5,026
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0           29,632                0           29,632           29,632
Commercial Kitchens:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0           16,124                0           16,124           16,124
    Eastern.......................................                0                0           22,774                0           22,774           22,774
    Pacific.......................................                0                0            2,386                0            2,386            2,386
    Southern......................................                0                0           37,431                0           37,431           37,431
    Western.......................................                0                0           16,151                0           16,151           16,151
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0           94,866                0           94,866           94,866
Construction:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0           40,091                0           40,091           40,091
    Eastern.......................................                0                0           55,085                0           55,085           55,085
    Pacific.......................................                0                0            4,992                0            4,992            4,992
    Southern......................................                0                0           90,641                0           90,641           90,641
    Western.......................................                0                0           41,364                0           41,364           41,364
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0          232,173                0          232,173          232,173
Drycleaning and Commercial Laundries:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0              906                0              906              906
    Eastern.......................................                0                0            1,536                0            1,536            1,536
    Pacific.......................................                0                0              160                0              160              160
    Southern......................................                0                0            2,150                0            2,150            2,150
    Western.......................................                0                0              951                0              951              951
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0            5,703                0            5,703            5,703
Landscaping and Facilities Support:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0            7,457                0            7,457            7,457
    Eastern.......................................                0                0           11,364                0           11,364           11,364
    Pacific.......................................                0                0              990                0              990              990
    Southern......................................                0                0           16,560                0           16,560           16,560
    Western.......................................                0                0            7,104                0            7,104            7,104
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0           43,475                0           43,475           43,475
Maintenance and Repair:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0            7,006                0            7,006            7,006
    Eastern.......................................                0                0            8,570                0            8,570            8,570
    Pacific.......................................                0                0              486                0              486              486
    Southern......................................                0                0           13,990                0           13,990           13,990
    Western.......................................                0                0            6,125                0            6,125            6,125
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0           36,177                0           36,177           36,177
Manufacturing:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0          122,175                0          122,175          122,175
    Eastern.......................................                0                0          114,309                0          114,309          114,309
    Pacific.......................................                0                0            1,501                0            1,501            1,501
    Southern......................................                0                0          144,730                0          144,730          144,730
    Western.......................................                0                0           55,535                0           55,535           55,535
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0          438,250                0          438,250          438,250
Oil and Gas:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0            1,123                0            1,123            1,123

[[Page 70885]]

 
    Eastern.......................................                0                0              674                0              674              674
    Southern......................................                0                0           10,578                0           10,578           10,578
    Western.......................................                0                0              781                0              781              781
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0           13,157                0           13,157           13,157
Postal and Delivery Services:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0            1,822                0            1,822            1,822
    Eastern.......................................                0                0            2,724                0            2,724            2,724
    Pacific.......................................                0                0              126                0              126              126
    Southern......................................                0                0            3,570                0            3,570            3,570
    Western.......................................                0                0            1,735                0            1,735            1,735
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0            9,978                0            9,978            9,978
Recreation and Amusement:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0              942                0              942              942
    Eastern.......................................                0                0            1,484                0            1,484            1,484
    Pacific.......................................                0                0               89                0               89               89
    Southern......................................                0                0            2,404                0            2,404            2,404
    Western.......................................                0                0            1,122                0            1,122            1,122
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0            6,041                0            6,041            6,041
Sanitation and Waste Removal:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0              827                0              827              827
    Eastern.......................................                0                0            1,252                0            1,252            1,252
    Pacific.......................................                0                0              105                0              105              105
    Southern......................................                0                0            1,780                0            1,780            1,780
    Western.......................................                0                0              796                0              796              796
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0            4,761                0            4,761            4,761
Telecommunications:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0            3,492                0            3,492            3,492
    Eastern.......................................                0                0            4,840                0            4,840            4,840
    Pacific.......................................                0                0              271                0              271              271
    Southern......................................                0                0            7,410                0            7,410            7,410
    Western.......................................                0                0            2,879                0            2,879            2,879
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0           18,893                0           18,893           18,893
Temporary Help Services:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0           18,741                0           18,741           18,741
    Eastern.......................................                0                0           23,206                0           23,206           23,206
    Pacific.......................................                0                0            2,482                0            2,482            2,482
    Southern......................................                0                0           70,315                0           70,315           70,315
    Western.......................................                0                0           21,815                0           21,815           21,815
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0          136,559                0          136,559          136,559
Transportation:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0            6,448                0            6,448            6,448
    Eastern.......................................                0                0            6,281                0            6,281            6,281
    Pacific.......................................                0                0              961                0              961              961
    Southern......................................                0                0           14,726                0           14,726           14,726
    Western.......................................                0                0            5,045                0            5,045            5,045
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0           33,461                0           33,461           33,461
Utilities:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0            4,482                0            4,482            4,482
    Eastern.......................................                0                0            6,029                0            6,029            6,029
    Pacific.......................................                0                0              112                0              112              112
    Southern......................................                0                0            9,053                0            9,053            9,053
    Western.......................................                0                0            2,970                0            2,970            2,970
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0           22,646                0           22,646           22,646
Warehousing:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0            3,599                0            3,599            3,599
    Eastern.......................................                0                0            5,038                0            5,038            5,038
    Pacific.......................................                0                0               94                0               94               94
    Southern......................................                0                0            7,018                0            7,018            7,018
    Western.......................................                0                0            3,351                0            3,351            3,351
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0           19,100                0           19,100           19,100
Non-Core:
    Alaskan.......................................                0                0                1                0                1                1

[[Page 70886]]

 
    Central.......................................                0                0          374,077                0          374,077          374,077
    Eastern.......................................                0                0          578,128                0          578,128          578,128
    Pacific.......................................                0                0           35,713                0           35,713           35,713
    Southern......................................                0                0          545,004                0          545,004          545,004
    Western.......................................                0                0          407,593                0          407,593          407,593
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        1,940,516                0        1,940,516        1,940,516
Total Costs for Returning Indoor Employee
 Acclimatization:
    Alaskan.......................................                0                0                2                0                2                2
    Central.......................................                0                0          619,667                0          619,667          619,667
    Eastern.......................................                0                0          853,071                0          853,071          853,071
    Pacific.......................................                0                0           51,065                0           51,065           51,065
    Southern......................................                0                0          996,021                0          996,021          996,021
    Western.......................................                0                0          586,847                0          586,847          586,847
                                                   -----------------------------------------------------------------------------------------------------
        Total.....................................                0                0        3,106,673                0        3,106,673        3,106,673
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                       Returning Outdoor Employee Acclimatization
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0           13,470                0           13,470           13,470
    Eastern.......................................                0                0            8,384                0            8,384            8,384
    Pacific.......................................                0                0              391                0              391              391
    Southern......................................                0                0           20,608                0           20,608           20,608
    Western.......................................                0                0           18,563                0           18,563           18,563
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0           61,417                0           61,417           61,417
Building Materials and Equipment Suppliers:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0            3,401                0            3,401            3,401
    Eastern.......................................                0                0            4,165                0            4,165            4,165
    Pacific.......................................                0                0              282                0              282              282
    Southern......................................                0                0            7,291                0            7,291            7,291
    Western.......................................                0                0            3,127                0            3,127            3,127
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0           18,266                0           18,266           18,266
Commercial Kitchens:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0            1,652                0            1,652            1,652
    Eastern.......................................                0                0            2,329                0            2,329            2,329
    Pacific.......................................                0                0              247                0              247              247
    Southern......................................                0                0            3,706                0            3,706            3,706
    Western.......................................                0                0            1,641                0            1,641            1,641
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0            9,576                0            9,576            9,576
Construction:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0           76,776                0           76,776           76,776
    Eastern.......................................                0                0          104,503                0          104,503          104,503
    Pacific.......................................                0                0            9,850                0            9,850            9,850
    Southern......................................                0                0          174,940                0          174,940          174,940
    Western.......................................                0                0           80,015                0           80,015           80,015
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0          446,085                0          446,085          446,085
Drycleaning and Commercial Laundries:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0              296                0              296              296
    Eastern.......................................                0                0              501                0              501              501
    Pacific.......................................                0                0               52                0               52               52
    Southern......................................                0                0              702                0              702              702
    Western.......................................                0                0              310                0              310              310
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0            1,862                0            1,862            1,862
Landscaping and Facilities Support:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0           16,658                0           16,658           16,658
    Eastern.......................................                0                0           25,377                0           25,377           25,377
    Pacific.......................................                0                0            2,343                0            2,343            2,343
    Southern......................................                0                0           37,002                0           37,002           37,002
    Western.......................................                0                0           15,747                0           15,747           15,747
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0           97,128                0           97,128           97,128
Maintenance and Repair:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0            5,744                0            5,744            5,744
    Eastern.......................................                0                0            7,059                0            7,059            7,059
    Pacific.......................................                0                0              407                0              407              407

[[Page 70887]]

 
    Southern......................................                0                0           11,300                0           11,300           11,300
    Western.......................................                0                0            5,098                0            5,098            5,098
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0           29,608                0           29,608           29,608
Manufacturing:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0           27,418                0           27,418           27,418
    Eastern.......................................                0                0           26,740                0           26,740           26,740
    Pacific.......................................                0                0              456                0              456              456
    Southern......................................                0                0           36,794                0           36,794           36,794
    Western.......................................                0                0           13,510                0           13,510           13,510
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0          104,918                0          104,918          104,918
Oil and Gas:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0            2,029                0            2,029            2,029
    Eastern.......................................                0                0            1,221                0            1,221            1,221
    Southern......................................                0                0           19,469                0           19,469           19,469
    Western.......................................                0                0            1,434                0            1,434            1,434
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0           24,153                0           24,153           24,153
Postal and Delivery Services:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0            1,486                0            1,486            1,486
    Eastern.......................................                0                0            2,205                0            2,205            2,205
    Pacific.......................................                0                0              107                0              107              107
    Southern......................................                0                0            2,881                0            2,881            2,881
    Western.......................................                0                0            1,363                0            1,363            1,363
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0            8,042                0            8,042            8,042
Recreation and Amusement:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0            1,284                0            1,284            1,284
    Eastern.......................................                0                0            2,024                0            2,024            2,024
    Pacific.......................................                0                0              121                0              121              121
    Southern......................................                0                0            3,259                0            3,259            3,259
    Western.......................................                0                0            1,524                0            1,524            1,524
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0            8,213                0            8,213            8,213
Sanitation and Waste Removal:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0              973                0              973              973
    Eastern.......................................                0                0            1,563                0            1,563            1,563
    Pacific.......................................                0                0              134                0              134              134
    Southern......................................                0                0            2,188                0            2,188            2,188
    Western.......................................                0                0              965                0              965              965
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0            5,823                0            5,823            5,823
Telecommunications:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0            2,897                0            2,897            2,897
    Eastern.......................................                0                0            4,014                0            4,014            4,014
    Pacific.......................................                0                0              225                0              225              225
    Southern......................................                0                0            6,146                0            6,146            6,146
    Western.......................................                0                0            2,388                0            2,388            2,388
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0           15,670                0           15,670           15,670
Temporary Help Services:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0            9,554                0            9,554            9,554
    Eastern.......................................                0                0           11,830                0           11,830           11,830
    Pacific.......................................                0                0            1,265                0            1,265            1,265
    Southern......................................                0                0           35,845                0           35,845           35,845
    Western.......................................                0                0           11,120                0           11,120           11,120
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0           69,614                0           69,614           69,614
Transportation:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0            8,425                0            8,425            8,425
    Eastern.......................................                0                0            8,060                0            8,060            8,060
    Pacific.......................................                0                0            1,280                0            1,280            1,280
    Southern......................................                0                0           19,123                0           19,123           19,123
    Western.......................................                0                0            6,496                0            6,496            6,496
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0           43,384                0           43,384           43,384
Utilities:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0            6,202                0            6,202            6,202
    Eastern.......................................                0                0            8,345                0            8,345            8,345

[[Page 70888]]

 
    Pacific.......................................                0                0              154                0              154              154
    Southern......................................                0                0           12,524                0           12,524           12,524
    Western.......................................                0                0            4,104                0            4,104            4,104
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0           31,329                0           31,329           31,329
Warehousing:
    Alaskan.......................................                0                0                0                0                0                0
    Central.......................................                0                0            1,505                0            1,505            1,505
    Eastern.......................................                0                0            2,106                0            2,106            2,106
    Pacific.......................................                0                0               39                0               39               39
    Southern......................................                0                0            2,934                0            2,934            2,934
    Western.......................................                0                0            1,401                0            1,401            1,401
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0            7,985                0            7,985            7,985
Non-Core:
    Alaskan.......................................                0                0                1                0                1                1
    Central.......................................                0                0          333,854                0          333,854          333,854
    Eastern.......................................                0                0          542,408                0          542,408          542,408
    Pacific.......................................                0                0           35,984                0           35,984           35,984
    Southern......................................                0                0          394,771                0          394,771          394,771
    Western.......................................                0                0          406,653                0          406,653          406,653
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        1,713,672                0        1,713,672        1,713,672
Total Costs for Returning Outdoor Employee
 Acclimatization:
    Alaskan.......................................                0                0                2                0                2                2
    Central.......................................                0                0          513,623                0          513,623          513,623
    Eastern.......................................                0                0          762,835                0          762,835          762,835
    Pacific.......................................                0                0           53,340                0           53,340           53,340
    Southern......................................                0                0          791,484                0          791,484          791,484
    Western.......................................                0                0          575,460                0          575,460          575,460
                                                   -----------------------------------------------------------------------------------------------------
        Total.....................................                0                0        2,696,744                0        2,696,744        2,696,744
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                       Rest Breaks at Initial Heat Trigger--Indoor
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing:
    Alaskan.......................................                0                0                8                2                6                6
    Central.......................................                0                0          494,281          115,332          378,949          378,949
    Eastern.......................................                0                0          285,957           66,723          219,234          219,234
    Pacific.......................................                0                0           15,605            3,641           11,964           11,964
    Southern......................................                0                0          795,586          185,637          609,949          609,949
    Western.......................................                0                0          661,911          154,446          507,465          507,465
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        2,253,348          525,781        1,727,567        1,727,567
Building Materials and Equipment Suppliers:
    Alaskan.......................................                0                0               30                7               23               23
    Central.......................................                0                0          542,090          126,488          415,602          415,602
    Eastern.......................................                0                0          654,987          152,830          502,157          502,157
    Pacific.......................................                0                0           48,716           11,367           37,349           37,349
    Southern......................................                0                0        1,259,531          293,891          965,641          965,641
    Western.......................................                0                0          489,137          114,132          375,005          375,005
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        2,994,491          698,714        2,295,776        2,295,776
Commercial Kitchens:
    Alaskan.......................................                0                0               73               17               56               56
    Central.......................................                0                0        1,857,283          433,366        1,423,917        1,423,917
    Eastern.......................................                0                0        2,613,642          609,850        2,003,792        2,003,792
    Pacific.......................................                0                0          436,216          101,784          334,433          334,433
    Southern......................................                0                0        5,793,449        1,351,805        4,441,644        4,441,644
    Western.......................................                0                0        1,917,574          447,434        1,470,140        1,470,140
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0       12,618,237        2,944,255        9,673,982        9,673,982
Construction:
    Alaskan.......................................                0                0              246               57              189              189
    Central.......................................                0                0        3,219,194          751,145        2,468,049        2,468,049
    Eastern.......................................                0                0        4,443,035        1,036,708        3,406,327        3,406,327
    Pacific.......................................                0                0          502,541          117,260          385,282          385,282
    Southern......................................                0                0        8,615,101        2,010,190        6,604,911        6,604,911
    Western.......................................                0                0        3,402,628          793,947        2,608,682        2,608,682
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0       20,182,745        4,709,307       15,473,438       15,473,438
Drycleaning and Commercial Laundries:
    Alaskan.......................................                0                0                4                1                3                3
    Central.......................................                0                0           87,222           20,352           66,870           66,870
    Eastern.......................................                0                0          147,275           34,364          112,911          112,911
    Pacific.......................................                0                0           17,020            3,971           13,048           13,048
    Southern......................................                0                0          239,057           55,780          183,277          183,277
    Western.......................................                0                0           92,951           21,689           71,263           71,263
                                                   -----------------------------------------------------------------------------------------------------

[[Page 70889]]

 
        Subtotal..................................                0                0          583,529          136,157          447,372          447,372
Landscaping and Facilities Support:
    Alaskan.......................................                0                0               75               17               57               57
    Central.......................................                0                0          705,904          164,711          541,193          541,193
    Eastern.......................................                0                0        1,087,767          253,812          833,955          833,955
    Pacific.......................................                0                0           99,076           23,118           75,959           75,959
    Southern......................................                0                0        1,798,521          419,655        1,378,866        1,378,866
    Western.......................................                0                0          685,161          159,871          525,290          525,290
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        4,376,505        1,021,184        3,355,320        3,355,320
Maintenance and Repair:
    Alaskan.......................................                0                0               34                8               26               26
    Central.......................................                0                0          675,747          157,674          518,072          518,072
    Eastern.......................................                0                0          834,797          194,786          640,011          640,011
    Pacific.......................................                0                0           52,772           12,313           40,458           40,458
    Southern......................................                0                0        1,556,716          363,234        1,193,482        1,193,482
    Western.......................................                0                0          608,916          142,080          466,836          466,836
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        3,728,982          870,096        2,858,886        2,858,886
Manufacturing:
    Alaskan.......................................                0                0              143               33              110              110
    Central.......................................                0                0        8,513,706        1,986,531        6,527,175        6,527,175
    Eastern.......................................                0                0        8,181,403        1,908,994        6,272,409        6,272,409
    Pacific.......................................                0                0          107,956           25,190           82,766           82,766
    Southern......................................                0                0       11,413,732        2,663,204        8,750,528        8,750,528
    Western.......................................                0                0        4,062,091          947,821        3,114,270        3,114,270
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0       32,279,030        7,531,774       24,747,257       24,747,257
Oil and Gas:
    Alaskan.......................................                0                0               86               20               66               66
    Central.......................................                0                0          113,630           26,514           87,116           87,116
    Eastern.......................................                0                0           64,273           14,997           49,276           49,276
    Southern......................................                0                0        1,170,506          273,118          897,388          897,388
    Western.......................................                0                0           77,990           18,198           59,792           59,792
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        1,426,485          332,846        1,093,638        1,093,638
Postal and Delivery Services:
    Alaskan.......................................                0                0                5                1                4                4
    Central.......................................                0                0          181,573           42,367          139,206          139,206
    Eastern.......................................                0                0          269,273           62,830          206,442          206,442
    Pacific.......................................                0                0           14,502            3,384           11,118           11,118
    Southern......................................                0                0          418,102           97,557          320,545          320,545
    Western.......................................                0                0          177,024           41,306          135,719          135,719
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        1,060,480          247,445          813,034          813,034
Recreation and Amusement:
    Alaskan.......................................                0                0                6                1                4                4
    Central.......................................                0                0          125,999           29,400           96,599           96,599
    Eastern.......................................                0                0          194,885           45,473          149,412          149,412
    Pacific.......................................                0                0           22,307            5,205           17,102           17,102
    Southern......................................                0                0          456,939          106,619          350,320          350,320
    Western.......................................                0                0          153,737           35,872          117,865          117,865
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0          953,872          222,570          731,302          731,302
Sanitation and Waste Removal:
    Alaskan.......................................                0                0               13                3               10               10
    Central.......................................                0                0           78,193           18,245           59,948           59,948
    Eastern.......................................                0                0          117,476           27,411           90,065           90,065
    Pacific.......................................                0                0           10,513            2,453            8,060            8,060
    Southern......................................                0                0          191,472           44,677          146,795          146,795
    Western.......................................                0                0           77,662           18,121           59,541           59,541
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0          475,329          110,910          364,419          364,419
Telecommunications:
    Alaskan.......................................                0                0               35                8               27               27
    Central.......................................                0                0          326,875           76,271          250,604          250,604
    Eastern.......................................                0                0          451,879          105,439          346,441          346,441
    Pacific.......................................                0                0           24,069            5,616           18,453           18,453
    Southern......................................                0                0          773,027          180,373          592,654          592,654
    Western.......................................                0                0          274,288           64,001          210,288          210,288
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        1,850,175          431,707        1,418,467        1,418,467
Temporary Help Services:
    Alaskan.......................................                0                0               11                2                8                8
    Central.......................................                0                0        1,764,509          411,719        1,352,790        1,352,790
    Eastern.......................................                0                0        2,223,951          518,922        1,705,029        1,705,029
    Pacific.......................................                0                0          237,694           55,462          182,232          182,232
    Southern......................................                0                0        7,717,829        1,800,827        5,917,003        5,917,003
    Western.......................................                0                0        2,078,922          485,082        1,593,840        1,593,840
                                                   -----------------------------------------------------------------------------------------------------

[[Page 70890]]

 
        Subtotal..................................                0                0       14,022,916        3,272,014       10,750,903       10,750,903
Transportation:
    Alaskan.......................................                0                0               78               18               60               60
    Central.......................................                0                0          644,184          150,310          493,874          493,874
    Eastern.......................................                0                0          626,041          146,076          479,965          479,965
    Pacific.......................................                0                0          114,259           26,660           87,598           87,598
    Southern......................................                0                0        1,718,290          400,934        1,317,356        1,317,356
    Western.......................................                0                0          519,628          121,246          398,381          398,381
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        3,622,479          845,245        2,777,234        2,777,234
Utilities:
    Alaskan.......................................                0                0               34                8               26               26
    Central.......................................                0                0          433,621          101,178          332,443          332,443
    Eastern.......................................                0                0          581,993          135,798          446,195          446,195
    Pacific.......................................                0                0           13,832            3,228           10,605           10,605
    Southern......................................                0                0        1,004,639          234,416          770,223          770,223
    Western.......................................                0                0          303,370           70,786          232,584          232,584
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        2,337,489          545,414        1,792,075        1,792,075
Warehousing:
    Alaskan.......................................                0                0                3                1                2                2
    Central.......................................                0                0          359,090           83,788          275,302          275,302
    Eastern.......................................                0                0          508,162          118,571          389,591          389,591
    Pacific.......................................                0                0           11,186            2,610            8,576            8,576
    Southern......................................                0                0          810,689          189,161          621,528          621,528
    Western.......................................                0                0          338,273           78,930          259,343          259,343
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        2,027,404          473,061        1,554,343        1,554,343
Non-Core:
    Alaskan.......................................                0                0            1,385              323            1,062            1,062
    Central.......................................                0                0       19,589,073        4,570,784       15,018,289       15,018,289
    Eastern.......................................                0                0       30,377,960        7,088,191       23,289,770       23,289,770
    Pacific.......................................                0                0        1,959,466          457,209        1,502,257        1,502,257
    Southern......................................                0                0       33,508,390        7,818,624       25,689,765       25,689,765
    Western.......................................                0                0       21,969,623        5,126,245       16,843,378       16,843,378
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0      107,405,896       25,061,376       82,344,521       82,344,521
Total Costs for Rest Breaks at Initial Heat
 Trigger--Indoor:
    Alaskan.......................................                0                0            2,268              529            1,739            1,739
    Central.......................................                0                0       39,712,173        9,266,174       30,445,999       30,445,999
    Eastern.......................................                0                0       53,664,756       12,521,777       41,142,980       41,142,980
    Pacific.......................................                0                0        3,687,730          860,470        2,827,260        2,827,260
    Southern......................................                0                0       79,241,576       18,489,701       60,751,875       60,751,875
    Western.......................................                0                0       37,890,887        8,841,207       29,049,680       29,049,680
                                                   -----------------------------------------------------------------------------------------------------
        Total.....................................                0                0      214,199,392       49,979,858      164,219,534      164,219,534
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                      Rest Breaks at Initial Heat Trigger--Outdoor
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing:
    Alaskan.......................................                0                0               26                5               21               21
    Central.......................................                0                0        1,447,844          289,569        1,158,275        1,158,275
    Eastern.......................................                0                0          854,788          170,958          683,830          683,830
    Pacific.......................................                0                0           45,903            9,181           36,722           36,722
    Southern......................................                0                0        2,356,557          471,311        1,885,246        1,885,246
    Western.......................................                0                0        1,932,124          386,425        1,545,700        1,545,700
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        6,637,243        1,327,449        5,309,794        5,309,794
Building Materials and Equipment Suppliers:
    Alaskan.......................................                0                0               19                4               15               15
    Central.......................................                0                0          331,125           66,225          264,900          264,900
    Eastern.......................................                0                0          402,033           80,407          321,626          321,626
    Pacific.......................................                0                0           30,235            6,047           24,188           24,188
    Southern......................................                0                0          807,047          161,409          645,638          645,638
    Western.......................................                0                0          309,009           61,802          247,207          247,207
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        1,879,467          375,893        1,503,574        1,503,574
Commercial Kitchens:
    Alaskan.......................................                0                0                8                2                6                6
    Central.......................................                0                0          188,883           37,777          151,106          151,106
    Eastern.......................................                0                0          264,517           52,903          211,613          211,613
    Pacific.......................................                0                0           43,628            8,726           34,903           34,903
    Southern......................................                0                0          568,982          113,796          455,186          455,186
    Western.......................................                0                0          193,195           38,639          154,556          154,556
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        1,259,213          251,843        1,007,371        1,007,371
Construction:
    Alaskan.......................................                0                0              441               88              353              353

[[Page 70891]]

 
    Central.......................................                0                0        6,152,988        1,230,598        4,922,390        4,922,390
    Eastern.......................................                0                0        8,382,560        1,676,512        6,706,048        6,706,048
    Pacific.......................................                0                0          995,358          199,072          796,286          796,286
    Southern......................................                0                0       16,580,548        3,316,110       13,264,438       13,264,438
    Western.......................................                0                0        6,576,720        1,315,344        5,261,376        5,261,376
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0       38,688,614        7,737,723       30,950,891       30,950,891
Drycleaning and Commercial Laundries:
    Alaskan.......................................                0                0                1                0                1                1
    Central.......................................                0                0           29,041            5,808           23,232           23,232
    Eastern.......................................                0                0           49,035            9,807           39,228           39,228
    Pacific.......................................                0                0            5,667            1,133            4,533            4,533
    Southern......................................                0                0           79,594           15,919           63,675           63,675
    Western.......................................                0                0           30,948            6,190           24,759           24,759
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0          194,286           38,857          155,429          155,429
Landscaping and Facilities Support:
    Alaskan.......................................                0                0              127               25              102              102
    Central.......................................                0                0        1,609,058          321,812        1,287,246        1,287,246
    Eastern.......................................                0                0        2,479,858          495,972        1,983,886        1,983,886
    Pacific.......................................                0                0          239,411           47,882          191,529          191,529
    Southern......................................                0                0        4,100,068          820,014        3,280,054        3,280,054
    Western.......................................                0                0        1,553,009          310,602        1,242,407        1,242,407
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        9,981,530        1,996,306        7,985,224        7,985,224
Maintenance and Repair:
    Alaskan.......................................                0                0               29                6               23               23
    Central.......................................                0                0          565,344          113,069          452,275          452,275
    Eastern.......................................                0                0          700,860          140,172          560,688          560,688
    Pacific.......................................                0                0           45,008            9,002           36,006           36,006
    Southern......................................                0                0        1,283,101          256,620        1,026,481        1,026,481
    Western.......................................                0                0          516,573          103,315          413,258          413,258
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        3,110,915          622,183        2,488,732        2,488,732
Manufacturing:
    Alaskan.......................................                0                0               51               10               41               41
    Central.......................................                0                0        1,954,406          390,881        1,563,525        1,563,525
    Eastern.......................................                0                0        1,956,554          391,311        1,565,244        1,565,244
    Pacific.......................................                0                0           33,381            6,676           26,705           26,705
    Southern......................................                0                0        2,961,164          592,233        2,368,931        2,368,931
    Western.......................................                0                0        1,008,707          201,741          806,965          806,965
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        7,914,264        1,582,853        6,331,411        6,331,411
Oil and Gas:
    Alaskan.......................................                0                0              164               33              131              131
    Central.......................................                0                0          209,271           41,854          167,417          167,417
    Eastern.......................................                0                0          118,661           23,732           94,929           94,929
    Southern......................................                0                0        2,196,724          439,345        1,757,379        1,757,379
    Western.......................................                0                0          145,839           29,168          116,671          116,671
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        2,670,659          534,132        2,136,527        2,136,527
Postal and Delivery Services:
    Alaskan.......................................                0                0                5                1                4                4
    Central.......................................                0                0          150,995           30,199          120,796          120,796
    Eastern.......................................                0                0          222,509           44,502          178,007          178,007
    Pacific.......................................                0                0           12,567            2,513           10,053           10,053
    Southern......................................                0                0          343,861           68,772          275,089          275,089
    Western.......................................                0                0          141,847           28,369          113,478          113,478
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0          871,785          174,357          697,428          697,428
Recreation and Amusement:
    Alaskan.......................................                0                0                8                2                6                6
    Central.......................................                0                0          175,190           35,038          140,152          140,152
    Eastern.......................................                0                0          271,067           54,213          216,853          216,853
    Pacific.......................................                0                0           30,901            6,180           24,721           24,721
    Southern......................................                0                0          631,736          126,347          505,389          505,389
    Western.......................................                0                0          213,035           42,607          170,428          170,428
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        1,321,937          264,387        1,057,550        1,057,550
Sanitation and Waste Removal:
    Alaskan.......................................                0                0               19                4               15               15
    Central.......................................                0                0           93,862           18,772           75,090           75,090
    Eastern.......................................                0                0          149,142           29,828          119,314          119,314
    Pacific.......................................                0                0           13,534            2,707           10,827           10,827
    Southern......................................                0                0          239,950           47,990          191,960          191,960
    Western.......................................                0                0           95,962           19,192           76,770           76,770
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0          592,470          118,494          473,976          473,976
Telecommunications:

[[Page 70892]]

 
    Alaskan.......................................                0                0               30                6               24               24
    Central.......................................                0                0          276,569           55,314          221,255          221,255
    Eastern.......................................                0                0          382,333           76,467          305,867          305,867
    Pacific.......................................                0                0           20,365            4,073           16,292           16,292
    Southern......................................                0                0          654,055          130,811          523,244          523,244
    Western.......................................                0                0          232,075           46,415          185,660          185,660
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        1,565,427          313,085        1,252,342        1,252,342
Temporary Help Services:
    Alaskan.......................................                0                0                6                1                4                4
    Central.......................................                0                0          917,544          183,509          734,035          734,035
    Eastern.......................................                0                0        1,156,453          231,291          925,162          925,162
    Pacific.......................................                0                0          123,601           24,720           98,881           98,881
    Southern......................................                0                0        4,013,267          802,653        3,210,613        3,210,613
    Western.......................................                0                0        1,081,038          216,208          864,831          864,831
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        7,291,908        1,458,382        5,833,527        5,833,527
Transportation:
    Alaskan.......................................                0                0              112               22               90               90
    Central.......................................                0                0          858,719          171,744          686,975          686,975
    Eastern.......................................                0                0          818,869          163,774          655,096          655,096
    Pacific.......................................                0                0          154,829           30,966          123,863          123,863
    Southern......................................                0                0        2,274,433          454,887        1,819,546        1,819,546
    Western.......................................                0                0          683,172          136,634          546,538          546,538
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        4,790,135          958,027        3,832,108        3,832,108
Utilities:
    Alaskan.......................................                0                0               47                9               38               38
    Central.......................................                0                0          612,027          122,405          489,621          489,621
    Eastern.......................................                0                0          821,643          164,329          657,315          657,315
    Pacific.......................................                0                0           19,465            3,893           15,572           15,572
    Southern......................................                0                0        1,417,789          283,558        1,134,231        1,134,231
    Western.......................................                0                0          427,591           85,518          342,073          342,073
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        3,298,562          659,712        2,638,849        2,638,849
Warehousing:
    Alaskan.......................................                0                0                1                0                1                1
    Central.......................................                0                0          153,135           30,627          122,508          122,508
    Eastern.......................................                0                0          216,708           43,342          173,366          173,366
    Pacific.......................................                0                0            4,770              954            3,816            3,816
    Southern......................................                0                0          345,721           69,144          276,577          276,577
    Western.......................................                0                0          144,258           28,852          115,406          115,406
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0          864,594          172,919          691,675          691,675
Non-Core:
    Alaskan.......................................                0                0            1,602              320            1,282            1,282
    Central.......................................                0                0       17,577,924        3,515,585       14,062,339       14,062,339
    Eastern.......................................                0                0       28,801,093        5,760,219       23,040,875       23,040,875
    Pacific.......................................                0                0        1,933,219          386,644        1,546,575        1,546,575
    Southern......................................                0                0       24,553,870        4,910,774       19,643,096       19,643,096
    Western.......................................                0                0       22,012,012        4,402,402       17,609,610       17,609,610
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0       94,879,721       18,975,944       75,903,777       75,903,777
Total Costs for Rest Breaks at Initial Heat
 Trigger--Outdoor:
    Alaskan.......................................                0                0            2,698              540            2,158            2,158
    Central.......................................                0                0       33,303,923        6,660,785       26,643,138       26,643,138
    Eastern.......................................                0                0       48,048,684        9,609,737       38,438,947       38,438,947
    Pacific.......................................                0                0        3,751,841          750,368        3,001,473        3,001,473
    Southern......................................                0                0       65,408,469       13,081,694       52,326,776       52,326,776
    Western.......................................                0                0       37,297,115        7,459,423       29,837,692       29,837,692
                                                   -----------------------------------------------------------------------------------------------------
        Total.....................................                0                0      187,812,730       37,562,546      150,250,184      150,250,184
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                           Effective Communication--Supervisor
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing:
    Alaskan.......................................                0                0               28                0               28               28
    Central.......................................                0                0        1,964,364                0        1,964,364        1,964,364
    Eastern.......................................                0                0        1,215,238                0        1,215,238        1,215,238
    Pacific.......................................                0                0           44,631                0           44,631           44,631
    Southern......................................                0                0        4,074,345                0        4,074,345        4,074,345
    Western.......................................                0                0        2,888,709                0        2,888,709        2,888,709
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0       10,187,315                0       10,187,315       10,187,315
Building Materials and Equipment Suppliers:
    Alaskan.......................................                0                0               36                0               36               36
    Central.......................................                0                0          765,503                0          765,503          765,503
    Eastern.......................................                0                0          961,428                0          961,428          961,428

[[Page 70893]]

 
    Pacific.......................................                0                0           54,471                0           54,471           54,471
    Southern......................................                0                0        2,264,317                0        2,264,317        2,264,317
    Western.......................................                0                0          764,695                0          764,695          764,695
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        4,810,451                0        4,810,451        4,810,451
Commercial Kitchens:
    Alaskan.......................................                0                0              131                0              131              131
    Central.......................................                0                0        3,143,911                0        3,143,911        3,143,911
    Eastern.......................................                0                0        4,732,451                0        4,732,451        4,732,451
    Pacific.......................................                0                0          380,104                0          380,104          380,104
    Southern......................................                0                0       10,585,830                0       10,585,830       10,585,830
    Western.......................................                0                0        3,623,278                0        3,623,278        3,623,278
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0       22,465,706                0       22,465,706       22,465,706
Construction:
    Alaskan.......................................                0                0              559                0              559              559
    Central.......................................                0                0        9,137,347                0        9,137,347        9,137,347
    Eastern.......................................                0                0       13,712,035                0       13,712,035       13,712,035
    Pacific.......................................                0                0          992,545                0          992,545          992,545
    Southern......................................                0                0       31,427,215                0       31,427,215       31,427,215
    Western.......................................                0                0       10,961,509                0       10,961,509       10,961,509
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0       66,231,210                0       66,231,210       66,231,210
Drycleaning and Commercial Laundries:
    Alaskan.......................................                0                0                4                0                4                4
    Central.......................................                0                0          105,390                0          105,390          105,390
    Eastern.......................................                0                0          192,692                0          192,692          192,692
    Pacific.......................................                0                0           15,964                0           15,964           15,964
    Southern......................................                0                0          369,774                0          369,774          369,774
    Western.......................................                0                0          127,300                0          127,300          127,300
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0          811,123                0          811,123          811,123
Landscaping and Facilities Support:
    Alaskan.......................................                0                0              156                0              156              156
    Central.......................................                0                0        2,235,263                0        2,235,263        2,235,263
    Eastern.......................................                0                0        3,759,687                0        3,759,687        3,759,687
    Pacific.......................................                0                0          263,459                0          263,459          263,459
    Southern......................................                0                0        7,391,500                0        7,391,500        7,391,500
    Western.......................................                0                0        2,457,942                0        2,457,942        2,457,942
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0       16,108,008                0       16,108,008       16,108,008
Maintenance and Repair:
    Alaskan.......................................                0                0               45                0               45               45
    Central.......................................                0                0        1,088,876                0        1,088,876        1,088,876
    Eastern.......................................                0                0        1,448,306                0        1,448,306        1,448,306
    Pacific.......................................                0                0           65,204                0           65,204           65,204
    Southern......................................                0                0        3,198,265                0        3,198,265        3,198,265
    Western.......................................                0                0        1,106,431                0        1,106,431        1,106,431
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        6,907,125                0        6,907,125        6,907,125
Manufacturing:
    Alaskan.......................................                0                0              151                0              151              151
    Central.......................................                0                0       10,477,364                0       10,477,364       10,477,364
    Eastern.......................................                0                0       10,527,247                0       10,527,247       10,527,247
    Pacific.......................................                0                0          116,915                0          116,915          116,915
    Southern......................................                0                0       18,442,859                0       18,442,859       18,442,859
    Western.......................................                0                0        5,656,280                0        5,656,280        5,656,280
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0       45,220,816                0       45,220,816       45,220,816
Oil and Gas:
    Alaskan.......................................                0                0              197                0              197              197
    Central.......................................                0                0          294,598                0          294,598          294,598
    Eastern.......................................                0                0          178,004                0          178,004          178,004
    Southern......................................                0                0        4,394,986                0        4,394,986        4,394,986
    Western.......................................                0                0          213,864                0          213,864          213,864
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        5,081,648                0        5,081,648        5,081,648
Postal and Delivery Services:
    Alaskan.......................................                0                0               10                0               10               10
    Central.......................................                0                0          380,967                0          380,967          380,967
    Eastern.......................................                0                0          605,787                0          605,787          605,787
    Pacific.......................................                0                0           22,894                0           22,894           22,894
    Southern......................................                0                0        1,074,645                0        1,074,645        1,074,645
    Western.......................................                0                0          409,080                0          409,080          409,080
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        2,493,383                0        2,493,383        2,493,383
Recreation and Amusement:
    Alaskan.......................................                0                0               33                0               33               33
    Central.......................................                0                0          660,935                0          660,935          660,935

[[Page 70894]]

 
    Eastern.......................................                0                0        1,121,133                0        1,121,133        1,121,133
    Pacific.......................................                0                0           54,251                0           54,251           54,251
    Southern......................................                0                0        2,414,130                0        2,414,130        2,414,130
    Western.......................................                0                0          906,381                0          906,381          906,381
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        5,156,864                0        5,156,864        5,156,864
Sanitation and Waste Removal:
    Alaskan.......................................                0                0               25                0               25               25
    Central.......................................                0                0          171,785                0          171,785          171,785
    Eastern.......................................                0                0          288,897                0          288,897          288,897
    Pacific.......................................                0                0           19,746                0           19,746           19,746
    Southern......................................                0                0          573,019                0          573,019          573,019
    Western.......................................                0                0          196,550                0          196,550          196,550
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        1,250,023                0        1,250,023        1,250,023
Telecommunications:
    Alaskan.......................................                0                0               36                0               36               36
    Central.......................................                0                0          425,813                0          425,813          425,813
    Eastern.......................................                0                0          643,399                0          643,399          643,399
    Pacific.......................................                0                0           28,284                0           28,284           28,284
    Southern......................................                0                0        1,330,181                0        1,330,181        1,330,181
    Western.......................................                0                0          403,641                0          403,641          403,641
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        2,831,354                0        2,831,354        2,831,354
Temporary Help Services:
    Alaskan.......................................                0                0               13                0               13               13
    Central.......................................                0                0        2,758,017                0        2,758,017        2,758,017
    Eastern.......................................                0                0        3,814,255                0        3,814,255        3,814,255
    Pacific.......................................                0                0          317,980                0          317,980          317,980
    Southern......................................                0                0       15,855,219                0       15,855,219       15,855,219
    Western.......................................                0                0        3,754,041                0        3,754,041        3,754,041
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0       26,499,525                0       26,499,525       26,499,525
Transportation:
    Alaskan.......................................                0                0              176                0              176              176
    Central.......................................                0                0        1,693,569                0        1,693,569        1,693,569
    Eastern.......................................                0                0        1,739,047                0        1,739,047        1,739,047
    Pacific.......................................                0                0          216,193                0          216,193          216,193
    Southern......................................                0                0        5,538,578                0        5,538,578        5,538,578
    Western.......................................                0                0        1,501,275                0        1,501,275        1,501,275
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0       10,688,839                0       10,688,839       10,688,839
Utilities:
    Alaskan.......................................                0                0               45                0               45               45
    Central.......................................                0                0          721,516                0          721,516          721,516
    Eastern.......................................                0                0        1,032,539                0        1,032,539        1,032,539
    Pacific.......................................                0                0           15,379                0           15,379           15,379
    Southern......................................                0                0        2,119,922                0        2,119,922        2,119,922
    Western.......................................                0                0          557,975                0          557,975          557,975
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        4,447,375                0        4,447,375        4,447,375
Warehousing:
    Alaskan.......................................                0                0                4                0                4                4
    Central.......................................                0                0          611,486                0          611,486          611,486
    Eastern.......................................                0                0          901,301                0          901,301          901,301
    Pacific.......................................                0                0           13,316                0           13,316           13,316
    Southern......................................                0                0        1,668,522                0        1,668,522        1,668,522
    Western.......................................                0                0          636,547                0          636,547          636,547
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        3,831,178                0        3,831,178        3,831,178
Non-Core:
    Alaskan.......................................                0                0            1,664                0            1,664            1,664
    Central.......................................                0                0       28,533,033                0       28,533,033       28,533,033
    Eastern.......................................                0                0       49,053,020                0       49,053,020       49,053,020
    Pacific.......................................                0                0        2,542,930                0        2,542,930        2,542,930
    Southern......................................                0                0       62,702,524                0       62,702,524       62,702,524
    Western.......................................                0                0       36,703,176                0       36,703,176       36,703,176
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0      179,536,346                0      179,536,346      179,536,346
Total Costs for Effective Communication--
 Supervisor:
    Alaskan.......................................                0                0            3,312                0            3,312            3,312
    Central.......................................                0                0       65,169,736                0       65,169,736       65,169,736
    Eastern.......................................                0                0       95,926,466                0       95,926,466       95,926,466
    Pacific.......................................                0                0        5,164,266                0        5,164,266        5,164,266
    Southern......................................                0                0      175,425,832                0      175,425,832      175,425,832
    Western.......................................                0                0       72,868,675                0       72,868,675       72,868,675
                                                   -----------------------------------------------------------------------------------------------------
        Total.....................................                0                0      414,558,288                0      414,558,288      414,558,288
--------------------------------------------------------------------------------------------------------------------------------------------------------

[[Page 70895]]

 
                                                            Effective Communication--Employee
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing:
    Alaskan.......................................                0                0               30                0               30               30
    Central.......................................                0                0        2,112,774                0        2,112,774        2,112,774
    Eastern.......................................                0                0        1,307,050                0        1,307,050        1,307,050
    Pacific.......................................                0                0           48,003                0           48,003           48,003
    Southern......................................                0                0        4,382,165                0        4,382,165        4,382,165
    Western.......................................                0                0        3,106,954                0        3,106,954        3,106,954
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0       10,956,976                0       10,956,976       10,956,976
Building Materials and Equipment Suppliers:
    Alaskan.......................................                0                0               44                0               44               44
    Central.......................................                0                0          942,412                0          942,412          942,412
    Eastern.......................................                0                0        1,184,054                0        1,184,054        1,184,054
    Pacific.......................................                0                0           67,085                0           67,085           67,085
    Southern......................................                0                0        2,791,746                0        2,791,746        2,791,746
    Western.......................................                0                0          942,394                0          942,394          942,394
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        5,927,736                0        5,927,736        5,927,736
Commercial Kitchens:
    Alaskan.......................................                0                0              189                0              189              189
    Central.......................................                0                0        4,479,892                0        4,479,892        4,479,892
    Eastern.......................................                0                0        6,743,062                0        6,743,062        6,743,062
    Pacific.......................................                0                0          537,452                0          537,452          537,452
    Southern......................................                0                0       15,142,940                0       15,142,940       15,142,940
    Western.......................................                0                0        5,158,261                0        5,158,261        5,158,261
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0       32,061,796                0       32,061,796       32,061,796
Construction:
    Alaskan.......................................                0                0              757                0              757              757
    Central.......................................                0                0       12,067,609                0       12,067,609       12,067,609
    Eastern.......................................                0                0       18,192,171                0       18,192,171       18,192,171
    Pacific.......................................                0                0        1,301,390                0        1,301,390        1,301,390
    Southern......................................                0                0       41,487,043                0       41,487,043       41,487,043
    Western.......................................                0                0       14,467,580                0       14,467,580       14,467,580
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0       87,516,549                0       87,516,549       87,516,549
Drycleaning and Commercial Laundries:
    Alaskan.......................................                0                0                5                0                5                5
    Central.......................................                0                0          132,867                0          132,867          132,867
    Eastern.......................................                0                0          242,929                0          242,929          242,929
    Pacific.......................................                0                0           20,126                0           20,126           20,126
    Southern......................................                0                0          466,178                0          466,178          466,178
    Western.......................................                0                0          160,489                0          160,489          160,489
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        1,022,592                0        1,022,592        1,022,592
Landscaping and Facilities Support:
    Alaskan.......................................                0                0              156                0              156              156
    Central.......................................                0                0        2,278,317                0        2,278,317        2,278,317
    Eastern.......................................                0                0        3,829,915                0        3,829,915        3,829,915
    Pacific.......................................                0                0          270,710                0          270,710          270,710
    Southern......................................                0                0        7,523,810                0        7,523,810        7,523,810
    Western.......................................                0                0        2,501,833                0        2,501,833        2,501,833
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0       16,404,742                0       16,404,742       16,404,742
Maintenance and Repair:
    Alaskan.......................................                0                0               56                0               56               56
    Central.......................................                0                0        1,372,758                0        1,372,758        1,372,758
    Eastern.......................................                0                0        1,825,895                0        1,825,895        1,825,895
    Pacific.......................................                0                0           82,203                0           82,203           82,203
    Southern......................................                0                0        4,032,088                0        4,032,088        4,032,088
    Western.......................................                0                0        1,394,890                0        1,394,890        1,394,890
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        8,707,890                0        8,707,890        8,707,890
Manufacturing:
    Alaskan.......................................                0                0              158                0              158              158
    Central.......................................                0                0       10,985,306                0       10,985,306       10,985,306
    Eastern.......................................                0                0       11,037,608                0       11,037,608       11,037,608
    Pacific.......................................                0                0          122,583                0          122,583          122,583
    Southern......................................                0                0       19,336,968                0       19,336,968       19,336,968
    Western.......................................                0                0        5,930,496                0        5,930,496        5,930,496
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0       47,413,118                0       47,413,118       47,413,118
Oil and Gas:
    Alaskan.......................................                0                0              222                0              222              222
    Central.......................................                0                0          331,463                0          331,463          331,463
    Eastern.......................................                0                0          200,341                0          200,341          200,341
    Southern......................................                0                0        4,954,004                0        4,954,004        4,954,004

[[Page 70896]]

 
    Western.......................................                0                0          240,985                0          240,985          240,985
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        5,727,015                0        5,727,015        5,727,015
Postal and Delivery Services:
    Alaskan.......................................                0                0               11                0               11               11
    Central.......................................                0                0          418,395                0          418,395          418,395
    Eastern.......................................                0                0          665,304                0          665,304          665,304
    Pacific.......................................                0                0           25,144                0           25,144           25,144
    Southern......................................                0                0        1,180,225                0        1,180,225        1,180,225
    Western.......................................                0                0          449,271                0          449,271          449,271
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        2,738,350                0        2,738,350        2,738,350
Recreation and Amusement:
    Alaskan.......................................                0                0               36                0               36               36
    Central.......................................                0                0          716,707                0          716,707          716,707
    Eastern.......................................                0                0        1,216,575                0        1,216,575        1,216,575
    Pacific.......................................                0                0           58,528                0           58,528           58,528
    Southern......................................                0                0        2,617,835                0        2,617,835        2,617,835
    Western.......................................                0                0          984,819                0          984,819          984,819
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        5,594,500                0        5,594,500        5,594,500
Sanitation and Waste Removal:
    Alaskan.......................................                0                0               25                0               25               25
    Central.......................................                0                0          169,213                0          169,213          169,213
    Eastern.......................................                0                0          284,571                0          284,571          284,571
    Pacific.......................................                0                0           19,451                0           19,451           19,451
    Southern......................................                0                0          564,437                0          564,437          564,437
    Western.......................................                0                0          193,607                0          193,607          193,607
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        1,231,303                0        1,231,303        1,231,303
Telecommunications:
    Alaskan.......................................                0                0               46                0               46               46
    Central.......................................                0                0          551,961                0          551,961          551,961
    Eastern.......................................                0                0          834,009                0          834,009          834,009
    Pacific.......................................                0                0           36,663                0           36,663           36,663
    Southern......................................                0                0        1,724,252                0        1,724,252        1,724,252
    Western.......................................                0                0          523,221                0          523,221          523,221
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        3,670,153                0        3,670,153        3,670,153
Temporary Help Services:
    Alaskan.......................................                0                0               13                0               13               13
    Central.......................................                0                0        2,716,714                0        2,716,714        2,716,714
    Eastern.......................................                0                0        3,757,134                0        3,757,134        3,757,134
    Pacific.......................................                0                0          313,218                0          313,218          313,218
    Southern......................................                0                0       15,617,778                0       15,617,778       15,617,778
    Western.......................................                0                0        3,697,822                0        3,697,822        3,697,822
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0       26,102,678                0       26,102,678       26,102,678
Transportation:
    Alaskan.......................................                0                0              194                0              194              194
    Central.......................................                0                0        1,859,957                0        1,859,957        1,859,957
    Eastern.......................................                0                0        1,909,903                0        1,909,903        1,909,903
    Pacific.......................................                0                0          237,434                0          237,434          237,434
    Southern......................................                0                0        6,082,726                0        6,082,726        6,082,726
    Western.......................................                0                0        1,648,771                0        1,648,771        1,648,771
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0       11,738,984                0       11,738,984       11,738,984
Utilities:
    Alaskan.......................................                0                0               73                0               73               73
    Central.......................................                0                0        1,160,185                0        1,160,185        1,160,185
    Eastern.......................................                0                0        1,660,306                0        1,660,306        1,660,306
    Pacific.......................................                0                0           24,729                0           24,729           24,729
    Southern......................................                0                0        3,408,801                0        3,408,801        3,408,801
    Western.......................................                0                0          897,215                0          897,215          897,215
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        7,151,308                0        7,151,308        7,151,308
Warehousing:
    Alaskan.......................................                0                0                5                0                5                5
    Central.......................................                0                0          671,562                0          671,562          671,562
    Eastern.......................................                0                0          989,851                0          989,851          989,851
    Pacific.......................................                0                0           14,625                0           14,625           14,625
    Southern......................................                0                0        1,832,450                0        1,832,450        1,832,450
    Western.......................................                0                0          699,086                0          699,086          699,086
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0        4,207,579                0        4,207,579        4,207,579
Non-Core:
    Alaskan.......................................                0                0            2,181                0            2,181            2,181
    Central.......................................                0                0       36,970,389                0       36,970,389       36,970,389
    Eastern.......................................                0                0       63,618,726                0       63,618,726       63,618,726

[[Page 70897]]

 
    Pacific.......................................                0                0        3,266,173                0        3,266,173        3,266,173
    Southern......................................                0                0       78,991,981                0       78,991,981       78,991,981
    Western.......................................                0                0       48,034,871                0       48,034,871       48,034,871
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................                0                0      230,884,322                0      230,884,322      230,884,322
Total Costs for Effective Communication--Employee:
    Alaskan.......................................                0                0            4,201                0            4,201            4,201
    Central.......................................                0                0       79,938,482                0       79,938,482       79,938,482
    Eastern.......................................                0                0      119,499,404                0      119,499,404      119,499,404
    Pacific.......................................                0                0        6,445,514                0        6,445,514        6,445,514
    Southern......................................                0                0      212,137,427                0      212,137,427      212,137,427
    Western.......................................                0                0       91,032,564                0       91,032,564       91,032,564
                                                   -----------------------------------------------------------------------------------------------------
        Total.....................................                0                0      509,057,592                0      509,057,592      509,057,592
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                            Total Costs for Requirements at or Above the Initial Heat Trigger
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing:
    Alaskan.......................................            2,582            2,874               94                7            2,668            2,961
    Central.......................................          290,531          323,438        6,809,497          404,901        6,695,127        6,728,034
    Eastern.......................................          162,505          180,911        4,152,610          237,681        4,077,434        4,095,840
    Pacific.......................................            1,935            2,155          177,064           12,822          166,177          166,397
    Southern......................................          260,422          289,919       12,814,196          656,948       12,417,670       12,447,167
    Western.......................................          232,476          258,807        8,976,858          540,871        8,668,463        8,694,794
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................          950,451        1,058,104       32,930,319        1,853,230       32,027,540       32,135,193
Building Materials and Equipment Suppliers:
    Alaskan.......................................            1,461            1,626              130               11            1,580            1,745
    Central.......................................          134,180          149,378        2,916,552          192,713        2,858,020        2,873,218
    Eastern.......................................          167,855          186,868        3,586,270          233,237        3,520,888        3,539,901
    Pacific.......................................            2,606            2,901          229,181           17,414          214,373          214,668
    Southern......................................          154,057          171,507        7,783,534          455,300        7,482,291        7,499,741
    Western.......................................          105,242          117,162        2,788,761          175,934        2,718,069        2,729,990
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................          565,401          629,442       17,304,428        1,074,608       16,795,222       16,859,262
Commercial Kitchens:
    Alaskan.......................................           10,503           11,693              408               19           10,892           12,082
    Central.......................................        1,231,606        1,371,104       12,451,003          471,143       13,211,467       13,350,965
    Eastern.......................................        1,835,684        2,043,603       18,279,032          662,753       19,451,963       19,659,882
    Pacific.......................................           39,669           44,162        1,785,332          110,509        1,714,492        1,718,985
    Southern......................................        1,635,856        1,821,141       38,770,869        1,465,601       38,941,123       39,126,409
    Western.......................................        1,092,042        1,215,732       13,661,407          486,073       14,267,375       14,391,066
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................        5,845,359        6,507,436       84,948,051        3,196,098       87,597,312       88,259,388
Construction:
    Alaskan.......................................           12,220           13,604            2,022              146           14,097           15,481
    Central.......................................          849,091          945,263       36,031,537        1,981,743       34,898,885       34,995,057
    Eastern.......................................        1,238,890        1,379,213       52,226,855        2,713,220       50,752,525       50,892,848
    Pacific.......................................           22,189           24,702        4,473,869          316,331        4,179,726        4,182,239
    Southern......................................        1,151,743        1,282,196      110,480,523        5,326,300      106,305,966      106,436,419
    Western.......................................          680,610          757,700       38,361,839        2,109,291       36,933,159       37,010,248
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................        3,954,742        4,402,677      241,576,645       12,447,030      233,084,357      233,532,292
Drycleaning and Commercial Laundries:
    Alaskan.......................................              185              206               14                1              198              219
    Central.......................................           22,582           25,140          403,678           26,160          400,100          402,658
    Eastern.......................................           43,947           48,924          715,273           44,171          715,048          720,026
    Pacific.......................................              834              928           67,476            5,105           63,205           63,299
    Southern......................................           32,751           36,461        1,271,287           71,699        1,232,339        1,236,049
    Western.......................................           21,418           23,843          463,272           27,878          456,811          459,237
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................          121,717          135,503        2,921,000          175,014        2,867,703        2,881,489
Landscaping and Facilities Support:
    Alaskan.......................................            3,686            4,104              517               43            4,161            4,578
    Central.......................................          222,053          247,204        7,611,700          486,523        7,347,230        7,372,381
    Eastern.......................................          359,816          400,571       12,350,876          749,784       11,960,908       12,001,663
    Pacific.......................................            6,309            7,023          981,924           71,000          917,233          917,948
    Southern......................................          286,418          318,859       22,550,982        1,239,668       21,597,731       21,630,172
    Western.......................................          214,983          239,333        8,126,642          470,473        7,871,153        7,895,503
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................        1,093,265        1,217,094       51,622,642        3,017,490       49,698,416       49,822,245
Maintenance and Repair:
    Alaskan.......................................            1,889            2,103              166               14            2,041            2,255
    Central.......................................          205,609          228,897        4,223,953          270,743        4,158,818        4,182,107
    Eastern.......................................          267,329          297,609        5,448,766          334,958        5,381,138        5,411,417
    Pacific.......................................            3,235            3,601          281,687           21,315          263,607          263,973
    Southern......................................          240,626          267,880       11,104,039          619,854       10,724,811       10,752,066
    Western.......................................          163,386          181,892        4,085,617          245,395        4,003,608        4,022,114
                                                   -----------------------------------------------------------------------------------------------------

[[Page 70898]]

 
        Subtotal..................................          882,074          981,982       25,144,229        1,492,279       24,534,023       24,633,932
Manufacturing:
    Alaskan.......................................            4,850            5,399              505               44            5,311            5,861
    Central.......................................        1,719,680        1,914,460       35,071,755        2,377,413       34,414,022       34,608,802
    Eastern.......................................        1,583,237        1,762,563       34,664,298        2,300,305       33,947,231       34,126,557
    Pacific.......................................            4,686            5,216          421,914           31,866          394,734          395,264
    Southern......................................        1,247,724        1,389,048       55,965,834        3,255,437       53,958,122       54,099,446
    Western.......................................          717,440          798,701       18,107,217        1,149,563       17,675,095       17,756,356
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................        5,277,616        5,875,387      144,231,525        9,114,627      140,394,515      140,992,285
Oil and Gas:
    Alaskan.......................................            2,991            3,329              675               53            3,612            3,951
    Central.......................................           34,495           38,402        1,106,175           68,368        1,072,303        1,076,210
    Eastern.......................................           20,770           23,123          654,966           38,729          637,008          639,360
    Southern......................................          173,902          193,599       14,164,399          712,463       13,625,838       13,645,535
    Western.......................................           19,853           22,102          773,687           47,365          746,174          748,423
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................          252,011          280,555       16,699,902          866,978       16,084,935       16,113,480
Postal and Delivery Services:
    Alaskan.......................................              918            1,022               31                2              947            1,051
    Central.......................................           78,862           87,795        1,320,012           72,566        1,326,308        1,335,240
    Eastern.......................................          116,555          129,757        2,043,229          107,332        2,052,452        2,065,653
    Pacific.......................................            1,164            1,295           88,403            5,897           83,669           83,801
    Southern......................................           82,930           92,323        3,383,667          166,330        3,300,268        3,309,661
    Western.......................................           58,555           65,188        1,353,434           69,675        1,342,314        1,348,946
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................          338,985          377,380        8,188,776          421,802        8,105,958        8,144,354
Recreation and Amusement:
    Alaskan.......................................            1,859            2,069               84                3            1,940            2,150
    Central.......................................          132,718          147,751        2,197,203           64,438        2,265,483        2,280,515
    Eastern.......................................          214,995          239,347        3,620,509           99,687        3,735,818        3,760,169
    Pacific.......................................            2,769            3,082          215,391           11,385          206,774          207,088
    Southern......................................          161,072          179,315        7,439,929          232,966        7,368,035        7,386,279
    Western.......................................          130,096          144,831        2,873,505           78,479        2,925,122        2,939,857
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................          643,508          716,396       16,346,621          486,958       16,503,172       16,576,059
Sanitation and Waste Removal:
    Alaskan.......................................              611              680               82                7              686              756
    Central.......................................           21,357           23,776          569,105           37,017          553,445          555,864
    Eastern.......................................           34,579           38,496          927,727           57,240          905,066          908,983
    Pacific.......................................              595              663           70,706            5,160           66,142           66,209
    Southern......................................           27,406           30,510        1,692,411           92,667        1,627,150        1,630,254
    Western.......................................           18,751           20,874          618,635           37,314          600,072          602,196
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................          103,299          115,000        3,878,665          229,404        3,752,560        3,764,261
Telecommunications:
    Alaskan.......................................              737              820              148               14              871              954
    Central.......................................           38,996           43,413        1,726,267          131,585        1,633,679        1,638,096
    Eastern.......................................           58,352           64,961        2,512,631          181,905        2,389,078        2,395,687
    Pacific.......................................              687              765          120,644            9,689          111,641          111,719
    Southern......................................           52,550           58,502        4,789,275          311,184        4,530,641        4,536,593
    Western.......................................           30,905           34,405        1,552,793          110,416        1,473,282        1,476,783
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................          182,227          202,867       10,701,758          744,793       10,139,192       10,159,832
Temporary Help Services:
    Alaskan.......................................              463              516               42                4              502              555
    Central.......................................          422,316          470,150        9,038,626          595,228        8,865,714        8,913,548
    Eastern.......................................          540,161          601,342       12,043,713          750,212       11,833,661       11,894,842
    Pacific.......................................           12,627           14,057        1,109,256           80,182        1,041,701        1,043,131
    Southern......................................          870,470          969,064       46,512,648        2,603,480       44,779,638       44,878,232
    Western.......................................          433,572          482,681       11,638,266          701,290       11,370,549       11,419,658
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................        2,279,609        2,537,809       80,342,552        4,730,396       77,891,765       78,149,965
Transportation:
    Alaskan.......................................            6,145            6,841              566               41            6,670            7,366
    Central.......................................          310,575          345,752        5,901,892          322,053        5,890,413        5,925,590
    Eastern.......................................          301,312          335,440        5,909,047          309,850        5,900,509        5,934,637
    Pacific.......................................            7,536            8,390          850,115           57,626          800,025          800,879
    Southern......................................          362,051          403,059       17,538,094          855,821       17,044,323       17,085,331
    Western.......................................          166,893          185,797        4,833,527          257,881        4,742,540        4,761,443
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................        1,154,512        1,285,278       35,033,240        1,803,272       34,384,480       34,515,247
Utilities:
    Alaskan.......................................              998            1,111              200               17            1,181            1,294
    Central.......................................           64,438           71,736        3,391,657          223,584        3,232,511        3,239,809
    Eastern.......................................           88,068           98,044        4,721,144          300,127        4,509,085        4,519,060
    Pacific.......................................              396              441           84,957            7,120           78,232           78,277
    Southern......................................           79,812           88,852        8,888,807          517,973        8,450,646        8,459,686
    Western.......................................           38,290           42,627        2,493,560          156,305        2,375,546        2,379,883
                                                   -----------------------------------------------------------------------------------------------------

[[Page 70899]]

 
        Subtotal..................................          272,003          302,811       19,580,325        1,205,126       18,647,201       18,678,009
Warehousing:
    Alaskan.......................................              201              224               14                1              214              237
    Central.......................................          102,280          113,864        2,085,718          114,415        2,073,583        2,085,167
    Eastern.......................................          148,725          165,570        3,022,555          161,913        3,009,367        3,026,212
    Pacific.......................................              674              750           51,470            3,564           48,580           48,656
    Southern......................................          126,638          140,981        5,223,716          258,305        5,092,049        5,106,393
    Western.......................................           86,989           96,842        2,088,531          107,782        2,067,739        2,077,591
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................          465,506          518,232       12,472,005          645,980       12,291,531       12,344,257
Non-Core:
    Alaskan.......................................           81,107           90,294            6,898              644           87,362           96,548
    Central.......................................        6,985,646        7,776,877      123,758,429        8,086,368      122,657,706      123,448,937
    Eastern.......................................       11,318,161       12,600,116      204,704,352       12,848,409      203,174,104      204,456,059
    Pacific.......................................          167,674          186,666       11,950,120          843,852       11,273,942       11,292,933
    Southern......................................        6,932,221        7,717,400      234,999,127       12,729,398      229,201,949      229,987,129
    Western.......................................        6,490,124        7,225,230      151,142,547        9,528,648      148,104,024      148,839,129
                                                   -----------------------------------------------------------------------------------------------------
        Subtotal..................................       31,974,933       35,596,583      726,561,474       44,037,320      714,499,087      718,120,736
Total:
    Alaskan.......................................          133,406          148,516           12,598            1,069          144,935          160,045
    Central.......................................       12,867,014       14,324,399      256,614,758       15,926,958      253,554,813      255,012,199
    Eastern.......................................       18,500,941       20,596,455      371,583,854       22,131,513      367,953,282      370,048,796
    Pacific.......................................          275,584          306,798       22,959,508        1,610,839       21,624,253       21,655,467
    Southern......................................       13,878,649       15,450,618      605,373,338       31,571,395      587,680,592      589,252,561
    Western.......................................       10,701,625       11,913,748      273,940,099       16,300,630      268,341,094      269,553,217
                                                   -----------------------------------------------------------------------------------------------------
        Total.....................................       56,357,219       62,740,535    1,530,484,155       87,542,404    1,499,298,970    1,505,682,286
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source: OSHA estimate.
Note: Due to rounding, figures in the columns and rows may not sum to the totals shown.

E. Requirements at or Above the High Heat Trigger
I. Rest Breaks
    All affected establishments would need to provide affected 
employees with rest breaks when the high heat trigger is met or 
exceeded. These rest breaks are different from those at the initial 
heat trigger in that they are scheduled, reoccurring at least every two 
hours. Employees would still be allowed rest breaks if needed as 
outlined under the initial heat trigger requirements, although OSHA 
estimates that these if-needed rest breaks would be shorter when the 
high heat trigger is met or exceeded because affected employees would 
also receive scheduled rest breaks (refer to section VIII.C.IV.E.I. for 
more details on the time estimated for high heat trigger rest breaks).
    Similar to the initial heat trigger rest breaks, OSHA calculated 
total high heat trigger rest break costs by estimating the number of 
hours by work shift type (daytime, evening, and overnight) in a given 
State that meets or exceeds the high heat trigger and normalizing these 
estimates to 8-hour work shift equivalents. These 8-hour work shift 
equivalents are then multiplied by the number of affected employees and 
the unit costs for both indoor and outdoor work conditions.
    As discussed in section VIII.C.IV.E.I., and detailed further in 
appendix A at the end of this section, OSHA estimates that under the 
proposed standard, the reduction in time spent on pacing (i.e., the 
increase in worker efficiency) will partially offset the added cost of 
time spent on if-needed rest breaks as well as scheduled rest breaks 
when the high heat trigger is met or exceeded for employees in Group 1 
(i.e., currently noncompliant with if-needed rest breaks as well as 
scheduled rest breaks). OSHA also estimates that reduced pacing (i.e., 
increase in worker efficiency) will partially offset the added cost of 
scheduled rest breaks when the high heat trigger is met or exceeded for 
employees in Group 2 (i.e., that are currently noncompliant with only 
scheduled rest breaks and currently compliant with if-needed rest 
breaks). Combining this estimated partial offset of the unit costs of 
rest breaks required when the high heat trigger is met or exceeded with 
data on the industry-level and/or State-level number of in-scope 
employees (discussed in section VIII.B.), baseline non-compliance rates 
(discussed in section VIII.C.II.A.), and State-level exposure to 
temperatures at or above the high heat trigger (discussed in section 
VIII.C.II.C.), OSHA estimates that approximately 71.72 percent of the 
total cost of compliance with rest breaks when the high heat trigger is 
met or exceeded (approximately $9.92 billion out of $13.83 billion) 
could be offset by avoided labor productivity losses due to pacing 
(i.e., avoided losses in worker efficiency).
II. Observation for Signs and Symptoms
    OSHA calculates the total costs for observing signs and symptoms 
when the high heat trigger is met or exceeded by multiplying the unit 
costs for both the designated person and at-risk worker by the number 
of affected employees and the number of 8-hour work shift equivalents. 
The method to calculate the number of work-shift equivalents is the 
same approach used in the calculation of total costs for rest breaks.
III. Hazard Alert
    OSHA also calculates the total costs for notifying employees of 
high heat conditions using 8-hour work shift equivalents. OSHA 
multiplies these 8-hour work shift equivalents by the number of 
affected establishments and the corresponding unit cost for a 
designated person to perform this requirement.
IV. Warning Signs for Excessively High Heat Areas
    OSHA assumed that the cost of placing warning signs for excessively 
high heat areas is only applicable to industries assumed to have 
radiant heat sources (as outlined in OSHA, 2024c and discussed in 
section VIII.C.IV.E.IV.). To calculate total costs of this provision,

[[Page 70900]]

OSHA multiplies the number of affected establishments with radiant heat 
sources by the unit cost for a warning sign. Similarly, OSHA multiplies 
the number of affected establishments by the unit cost for a designated 
person to place that warning sign in an excessively high heat area.
    Table VIII.C.25. shows the annualized one-time, annual, and total 
annualized costs for each of these requirements by industry category 
and region, discounted (2 percent over a 10-year period) and 
undiscounted. Note that the best available evidence OSHA employed in 
this analysis showed no days exceeding the high heat trigger in Alaska 
and therefore, the agency estimated that most industries in Alaska will 
not have costs of compliance for requirements at or above the high heat 
trigger. This may understate the effects in establishments where 
employees are exposed to process heat. However, OSHA identified no data 
that would allow an adjustment for this consideration but welcomes 
comment on the issue.

                                      Table VIII.C.25--Total Costs--Requirements at or Above the High Heat Trigger
                                                                         [2023$]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                          One-time annualized                                                   Total annualized
                Industry category                 ----------------------------------      Annual         Annual cost   ---------------------------------
                                                          0%               2%                              savings             0%               2%
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                        Rest Breaks at High Heat Trigger--Indoor
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing:
    Central......................................               $0               $0       $10,576,482       $8,053,295       $2,523,187       $2,523,187
    Eastern......................................                0                0         8,784,224        6,685,916        2,098,307        2,098,307
    Pacific......................................                0                0           138,806          105,610           33,196           33,196
    Southern.....................................                0                0        47,848,109       36,415,246       11,432,863       11,432,863
    Western......................................                0                0         6,577,885        5,037,349        1,540,536        1,540,536
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0        73,925,505       56,297,416       17,628,090       17,628,090
Building Materials and Equipment Suppliers:
    Central......................................                0                0         9,303,121        7,086,386        2,216,735        2,216,735
    Eastern......................................                0                0        16,643,764       12,668,300        3,975,464        3,975,464
    Pacific......................................                0                0           420,880          320,205          100,675          100,675
    Southern.....................................                0                0        68,319,209       51,995,293       16,323,916       16,323,916
    Western......................................                0                0         6,134,338        4,688,454        1,445,885        1,445,885
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0       100,821,312       76,758,637       24,062,675       24,062,675
Commercial Kitchens:
    Central......................................                0                0        60,520,663       46,100,638       14,420,026       14,420,026
    Eastern......................................                0                0       134,221,171      102,165,211       32,055,959       32,055,959
    Pacific......................................                0                0         4,437,895        3,376,261        1,061,634        1,061,634
    Southern.....................................                0                0       511,271,461      389,110,577      122,160,884      122,160,884
    Western......................................                0                0        52,350,165       39,989,637       12,360,528       12,360,528
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0       762,801,355      580,742,324      182,059,030      182,059,030
Construction:
    Central......................................                0                0        70,052,483       53,357,614       16,694,869       16,694,869
    Eastern......................................                0                0       159,083,213      121,101,655       37,981,559       37,981,559
    Pacific......................................                0                0         4,895,384        3,724,409        1,170,975        1,170,975
    Southern.....................................                0                0       618,272,678      470,546,413      147,726,264      147,726,264
    Western......................................                0                0        63,400,197       48,418,585       14,981,612       14,981,612
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0       915,703,956      697,148,676      218,555,280      218,555,280
Drycleaning and Commercial Laundries:
    Central......................................                0                0         1,543,453        1,175,718          367,735          367,735
    Eastern......................................                0                0         4,226,300        3,216,917        1,009,383        1,009,383
    Pacific......................................                0                0           152,778          116,231           36,547           36,547
    Southern.....................................                0                0        13,967,752       10,630,371        3,337,381        3,337,381
    Western......................................                0                0         1,365,680        1,043,429          322,251          322,251
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0        21,255,963       16,182,666        5,073,297        5,073,297
Landscaping and Facilities Support:
    Central......................................                0                0        11,258,311        8,576,633        2,681,678        2,681,678
    Eastern......................................                0                0        29,789,561       22,677,209        7,112,351        7,112,351
    Pacific......................................                0                0           877,456          667,554          209,902          209,902
    Southern.....................................                0                0        98,622,223       75,057,866       23,564,358       23,564,358
    Western......................................                0                0         9,857,882        7,529,435        2,328,447        2,328,447
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0       150,405,433      114,508,696       35,896,737       35,896,737
Maintenance and Repair:
    Central......................................                0                0        12,180,429        9,277,696        2,902,733        2,902,733
    Eastern......................................                0                0        24,027,523       18,289,697        5,737,826        5,737,826
    Pacific......................................                0                0           468,728          356,611          112,117          112,117
    Southern.....................................                0                0        91,248,519       69,446,128       21,802,391       21,802,391
    Western......................................                0                0         9,080,801        6,936,248        2,144,553        2,144,553
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0       137,006,001      104,306,380       32,699,620       32,699,620
Manufacturing:
    Central......................................                0                0       144,486,598      110,031,414       34,455,184       34,455,184
    Eastern......................................                0                0       208,190,782      158,448,947       49,741,835       49,741,835
    Pacific......................................                0                0           935,094          711,392          223,702          223,702
    Southern.....................................                0                0       593,557,344      451,731,773      141,825,572      141,825,572
    Western......................................                0                0        47,373,376       36,217,813       11,155,562       11,155,562
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0       994,543,195      757,141,340      237,401,855      237,401,855

[[Page 70901]]

 
Oil and Gas:
    Central......................................                0                0         1,667,275        1,270,325          396,950          396,950
    Eastern......................................                0                0         1,374,956        1,046,323          328,634          328,634
    Southern.....................................                0                0        75,216,238       57,244,908       17,971,330       17,971,330
    Western......................................                0                0           939,050          716,692          222,358          222,358
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0        79,197,520       60,278,247       18,919,272       18,919,272
Postal and Delivery Services:
    Central......................................                0                0         3,723,031        2,835,752          887,279          887,279
    Eastern......................................                0                0         8,437,591        6,422,458        2,015,134        2,015,134
    Pacific......................................                0                0           135,720          103,249           32,471           32,471
    Southern.....................................                0                0        26,176,215       19,921,838        6,254,377        6,254,377
    Western......................................                0                0         2,784,618        2,127,847          656,770          656,770
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0        41,257,175       31,411,144        9,846,030        9,846,030
Recreation and Amusement:
    Central......................................                0                0         4,665,130        3,553,632        1,111,498        1,111,498
    Eastern......................................                0                0        11,919,186        9,072,587        2,846,599        2,846,599
    Pacific......................................                0                0           237,458          180,652           56,806           56,806
    Southern.....................................                0                0        44,104,195       33,566,359       10,537,836       10,537,836
    Western......................................                0                0         4,864,366        3,716,150        1,148,216        1,148,216
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0        65,790,335       50,089,379       15,700,955       15,700,955
Sanitation and Waste Removal:
    Central......................................                0                0         1,230,874          937,606          293,268          293,268
    Eastern......................................                0                0         2,949,063        2,244,815          704,248          704,248
    Pacific......................................                0                0            92,266           70,195           22,070           22,070
    Southern.....................................                0                0        10,641,076        8,098,531        2,542,545        2,542,545
    Western......................................                0                0           997,007          761,835          235,171          235,171
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0        15,910,286       12,112,982        3,797,303        3,797,303
Telecommunications:
    Central......................................                0                0         4,853,408        3,697,024        1,156,384        1,156,384
    Eastern......................................                0                0        11,279,180        8,585,138        2,694,041        2,694,041
    Pacific......................................                0                0           206,445          157,053           49,392           49,392
    Southern.....................................                0                0        38,488,372       29,292,248        9,196,124        9,196,124
    Western......................................                0                0         3,629,760        2,771,557          858,203          858,203
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0        58,457,165       44,503,020       13,954,145       13,954,145
Temporary Help Services:
    Central......................................                0                0        25,313,302       19,287,681        6,025,621        6,025,621
    Eastern......................................                0                0        62,178,214       47,326,395       14,851,819       14,851,819
    Pacific......................................                0                0         2,126,287        1,617,581          508,707          508,707
    Southern.....................................                0                0       426,178,792      324,351,948      101,826,844      101,826,844
    Western......................................                0                0        29,005,005       22,159,171        6,845,833        6,845,833
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0       544,801,600      414,742,776      130,058,824      130,058,824
Transportation:
    Central......................................                0                0        13,351,018       10,169,447        3,181,571        3,181,571
    Eastern......................................                0                0        20,126,557       15,318,830        4,807,727        4,807,727
    Pacific......................................                0                0         1,051,426          799,912          251,514          251,514
    Southern.....................................                0                0       107,284,179       81,650,279       25,633,900       25,633,900
    Western......................................                0                0         9,283,022        7,087,575        2,195,447        2,195,447
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0       151,096,202      115,026,042       36,070,160       36,070,160
Utilities:
    Central......................................                0                0         7,982,072        6,079,447        1,902,625        1,902,625
    Eastern......................................                0                0        16,193,659       12,325,758        3,867,901        3,867,901
    Pacific......................................                0                0           115,621           87,979           27,642           27,642
    Southern.....................................                0                0        58,183,741       44,281,543       13,902,198       13,902,198
    Western......................................                0                0         4,643,754        3,546,260        1,097,494        1,097,494
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0        87,118,847       66,320,986       20,797,860       20,797,860
Warehousing:
    Central......................................                0                0         7,749,473        5,903,019        1,846,455        1,846,455
    Eastern......................................                0                0        16,298,484       12,405,449        3,893,035        3,893,035
    Pacific......................................                0                0           102,820           78,225           24,596           24,596
    Southern.....................................                0                0        49,918,912       37,991,496       11,927,417       11,927,417
    Western......................................                0                0         5,276,312        4,032,474        1,243,838        1,243,838
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0        79,346,001       60,410,661       18,935,340       18,935,340
Non-Core:
    Central......................................                0                0       303,342,032      231,097,706       72,244,327       72,244,327
    Eastern......................................                0                0       803,385,621      611,525,275      191,860,345      191,860,345
    Pacific......................................                0                0        17,129,327       13,031,481        4,097,846        4,097,846
    Southern.....................................                0                0     1,850,916,061    1,408,664,889      442,251,172      442,251,172
    Western......................................                0                0       283,757,707      216,816,012       66,941,695       66,941,695
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0     3,258,530,748    2,481,135,363      777,395,385      777,395,385

[[Page 70902]]

 
Total Costs for Rest Breaks at High Heat Trigger--
 Indoor:
    Central......................................                0                0       693,799,156      528,491,032      165,308,125      165,308,125
    Eastern......................................                0                0     1,539,109,050    1,171,526,881      367,582,169      367,582,169
    Pacific......................................                0                0        33,524,391       25,504,598        8,019,793        8,019,793
    Southern.....................................                0                0     4,730,215,075    3,599,997,704    1,130,217,372    1,130,217,372
    Western......................................                0                0       541,320,924      413,596,523      127,724,401      127,724,401
        Total....................................                0                0     7,537,968,597    5,739,116,737    1,798,851,859    1,798,851,859
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                        Rest Breaks at High Heat Trigger--Outdoor
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing:
    Central......................................                0                0        30,421,837       20,207,084       10,214,753       10,214,753
    Eastern......................................                0                0        25,905,352       17,200,149        8,705,204        8,705,204
    Pacific......................................                0                0           401,164          266,259          134,906          134,906
    Southern.....................................                0                0       139,227,176       92,433,271       46,793,905       46,793,905
    Western......................................                0                0        18,824,524       12,575,462        6,249,063        6,249,063
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0       214,780,053      142,682,223       72,097,830       72,097,830
Building Materials and Equipment Suppliers:
    Central......................................                0                0         5,468,916        3,634,104        1,834,811        1,834,811
    Eastern......................................                0                0        10,027,967        6,658,390        3,369,577        3,369,577
    Pacific......................................                0                0           255,772          169,751           86,021           86,021
    Southern.....................................                0                0        43,109,868       28,620,964       14,488,903       14,488,903
    Western......................................                0                0         3,801,057        2,534,221        1,266,836        1,266,836
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0        62,663,579       41,617,431       21,046,149       21,046,149
Commercial Kitchens:
    Central......................................                0                0         5,882,754        3,909,101        1,973,653        1,973,653
    Eastern......................................                0                0        13,027,811        8,650,431        4,377,380        4,377,380
    Pacific......................................                0                0           433,257          287,536          145,722          145,722
    Southern.....................................                0                0        48,771,686       32,379,881       16,391,805       16,391,805
    Western......................................                0                0         5,042,717        3,360,397        1,682,319        1,682,319
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0        73,158,225       48,587,346       24,570,879       24,570,879
Construction:
    Central......................................                0                0       132,944,386       88,332,828       44,611,559       44,611,559
    Eastern......................................                0                0       293,649,877      195,001,930       98,647,947       98,647,947
    Pacific......................................                0                0         9,517,395        6,316,496        3,200,899        3,200,899
    Southern.....................................                0                0     1,169,092,863      776,171,055      392,921,808      392,921,808
    Western......................................                0                0       121,291,239       80,799,556       40,491,683       40,491,683
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0     1,726,495,760    1,146,621,865      579,873,896      579,873,896
Drycleaning and Commercial Laundries:
    Central......................................                0                0           504,941          335,534          169,407          169,407
    Eastern......................................                0                0         1,382,635          918,064          464,571          464,571
    Pacific......................................                0                0            49,982           33,171           16,811           16,811
    Southern.....................................                0                0         4,569,552        3,033,762        1,535,790        1,535,790
    Western......................................                0                0           446,782          297,780          149,002          149,002
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0         6,953,891        4,618,311        2,335,580        2,335,580
Landscaping and Facilities Support:
    Central......................................                0                0        25,722,284       17,093,146        8,629,138        8,629,138
    Eastern......................................                0                0        66,910,496       44,432,777       22,477,719       22,477,719
    Pacific......................................                0                0         2,078,513        1,379,437          699,076          699,076
    Southern.....................................                0                0       221,198,874      146,855,494       74,343,380       74,343,380
    Western......................................                0                0        22,088,210       14,716,664        7,371,546        7,371,546
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0       337,998,378      224,477,518      113,520,859      113,520,859
Maintenance and Repair:
    Central......................................                0                0        10,028,628        6,663,497        3,365,131        3,365,131
    Eastern......................................                0                0        19,822,596       13,162,703        6,659,893        6,659,893
    Pacific......................................                0                0           393,120          260,906          132,214          132,214
    Southern.....................................                0                0        73,735,754       48,953,791       24,781,963       24,781,963
    Western......................................                0                0         7,565,618        5,041,201        2,524,416        2,524,416
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0       111,545,715       74,082,098       37,463,618       37,463,618
Manufacturing:
    Central......................................                0                0        33,375,481       22,171,602       11,203,879       11,203,879
    Eastern......................................                0                0        50,014,418       33,205,559       16,808,859       16,808,859
    Pacific......................................                0                0           284,377          188,727           95,651           95,651
    Southern.....................................                0                0       152,996,536      101,574,747       51,421,789       51,421,789
    Western......................................                0                0        11,220,859        7,484,528        3,736,331        3,736,331
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0       247,891,671      164,625,163       83,266,508       83,266,508
Oil and Gas:
    Central......................................                0                0         2,987,040        1,985,344        1,001,697        1,001,697
    Eastern......................................                0                0         2,472,347        1,641,236          831,110          831,110
    Southern.....................................                0                0       138,600,039       92,018,389       46,581,650       46,581,650

[[Page 70903]]

 
    Western......................................                0                0         1,710,867        1,139,088          571,779          571,779
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0       145,770,293       96,784,057       48,986,237       48,986,237
Postal and Delivery Services:
    Central......................................                0                0         3,054,541        2,029,561        1,024,980        1,024,980
    Eastern......................................                0                0         6,863,635        4,557,461        2,306,173        2,306,173
    Pacific......................................                0                0           115,557           76,687           38,870           38,870
    Southern.....................................                0                0        21,099,271       14,007,996        7,091,276        7,091,276
    Western......................................                0                0         2,207,011        1,471,109          735,902          735,902
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0        33,340,014       22,142,814       11,197,200       11,197,200
Recreation and Amusement:
    Central......................................                0                0         6,372,352        4,234,424        2,137,928        2,137,928
    Eastern......................................                0                0        16,280,661       10,810,418        5,470,244        5,470,244
    Pacific......................................                0                0           323,230          214,513          108,717          108,717
    Southern.....................................                0                0        59,913,596       39,777,337       20,136,259       20,136,259
    Western......................................                0                0         6,637,770        4,423,522        2,214,248        2,214,248
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0        89,527,609       59,460,214       30,067,395       30,067,395
Sanitation and Waste Removal:
    Central......................................                0                0         1,445,654          960,612          485,042          485,042
    Eastern......................................                0                0         3,664,148        2,433,075        1,231,073        1,231,073
    Pacific......................................                0                0           117,244           77,811           39,433           39,433
    Southern.....................................                0                0        13,100,478        8,697,486        4,402,992        4,402,992
    Western......................................                0                0         1,172,994          781,984          391,010          391,010
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0        19,500,518       12,950,968        6,549,550        6,549,550
Telecommunications:
    Central......................................                0                0         4,034,928        2,681,188        1,353,740        1,353,740
    Eastern......................................                0                0         9,377,005        6,226,155        3,150,850        3,150,850
    Pacific......................................                0                0           171,635          113,903           57,732           57,732
    Southern.....................................                0                0        31,997,519       21,243,470       10,754,049       10,754,049
    Western......................................                0                0         3,017,642        2,010,016        1,007,626        1,007,626
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0        48,598,728       32,274,732       16,323,997       16,323,997
Temporary Help Services:
    Central......................................                0                0        12,933,584        8,596,785        4,336,798        4,336,798
    Eastern......................................                0                0        31,769,349       21,094,027       10,675,322       10,675,322
    Pacific......................................                0                0         1,086,406          720,978          365,428          365,428
    Southern.....................................                0                0       217,751,879      144,568,138       73,183,741       73,183,741
    Western......................................                0                0        14,819,823        9,876,648        4,943,175        4,943,175
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0       278,361,040      184,856,576       93,504,464       93,504,464
Transportation:
    Central......................................                0                0        17,389,771       11,555,006        5,834,765        5,834,765
    Eastern......................................                0                0        25,857,112       17,168,009        8,689,103        8,689,103
    Pacific......................................                0                0         1,401,978          930,441          471,537          471,537
    Southern.....................................                0                0       139,702,133       92,749,396       46,952,737       46,952,737
    Western......................................                0                0        12,071,618        8,039,763        4,031,855        4,031,855
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0       196,422,612      130,442,615       65,979,997       65,979,997
Utilities:
    Central......................................                0                0        11,068,721        7,354,144        3,714,577        3,714,577
    Eastern......................................                0                0        22,460,044       14,913,008        7,547,036        7,547,036
    Pacific......................................                0                0           159,839          106,099           53,740           53,740
    Southern.....................................                0                0        80,684,859       53,567,225       27,117,634       27,117,634
    Western......................................                0                0         6,429,129        4,282,922        2,146,208        2,146,208
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0       120,802,593       80,223,398       40,579,195       40,579,195
Warehousing:
    Central......................................                0                0         3,247,215        2,157,740        1,089,476        1,089,476
    Eastern......................................                0                0         6,829,456        4,534,583        2,294,873        2,294,873
    Pacific......................................                0                0            43,084           28,594           14,491           14,491
    Southern.....................................                0                0        20,917,223       13,887,092        7,030,131        7,030,131
    Western......................................                0                0         2,210,901        1,473,997          736,905          736,905
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0        33,247,880       22,082,005       11,165,875       11,165,875
Non-Core:
    Central......................................                0                0       246,952,116      164,137,970       82,814,146       82,814,146
    Eastern......................................                0                0       727,561,870      483,115,960      244,445,911      244,445,911
    Pacific......................................                0                0        16,378,766       10,869,733        5,509,033        5,509,033
    Southern.....................................                0                0     1,291,042,547      857,129,196      433,913,351      433,913,351
    Western......................................                0                0       262,677,028      175,094,081       87,582,947       87,582,947
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0     2,544,612,328    1,690,346,939      854,265,389      854,265,389
Total Costs for Rest Breaks at High Heat Trigger--
 Outdoor:
    Central......................................                0                0       553,835,149      368,039,670      185,795,480      185,795,480
    Eastern......................................                0                0     1,333,876,779      885,723,935      448,152,844      448,152,844

[[Page 70904]]

 
    Pacific......................................                0                0        33,211,320       22,041,040       11,170,280       11,170,280
    Southern.....................................                0                0     3,867,511,852    2,567,668,689    1,299,843,163    1,299,843,163
    Western......................................                0                0       503,235,789      335,402,938      167,832,851      167,832,851
--------------------------------------------------------------------------------------------------------------------------------------------------------
        Total....................................                0                0     6,291,670,889    4,178,876,272    2,112,794,617    2,112,794,617
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                  Observation for Signs and Symptoms--Designated Person
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing:
    Central......................................                0                0           559,511                0          559,511          559,511
    Eastern......................................                0                0           406,548                0          406,548          406,548
    Pacific......................................                0                0             6,788                0            6,788            6,788
    Southern.....................................                0                0         2,084,391                0        2,084,391        2,084,391
    Western......................................                0                0           909,503                0          909,503          909,503
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0         3,966,740                0        3,966,740        3,966,740
Building Materials and Equipment Suppliers:
    Central......................................                0                0           207,109                0          207,109          207,109
    Eastern......................................                0                0           297,661                0          297,661          297,661
    Pacific......................................                0                0             7,987                0            7,987            7,987
    Southern.....................................                0                0         1,133,972                0        1,133,972        1,133,972
    Western......................................                0                0           255,007                0          255,007          255,007
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0         1,901,736                0        1,901,736        1,901,736
Commercial Kitchens:
    Central......................................                0                0           836,294                0          836,294          836,294
    Eastern......................................                0                0         1,474,289                0        1,474,289        1,474,289
    Pacific......................................                0                0            52,685                0           52,685           52,685
    Southern.....................................                0                0         5,113,140                0        5,113,140        5,113,140
    Western......................................                0                0         1,225,216                0        1,225,216        1,225,216
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0         8,701,625                0        8,701,625        8,701,625
Construction:
    Central......................................                0                0         2,502,225                0        2,502,225        2,502,225
    Eastern......................................                0                0         4,636,411                0        4,636,411        4,636,411
    Pacific......................................                0                0           153,665                0          153,665          153,665
    Southern.....................................                0                0        16,364,447                0       16,364,447       16,364,447
    Western......................................                0                0         3,765,603                0        3,765,603        3,765,603
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0        27,422,352                0       27,422,352       27,422,352
Drycleaning and Commercial Laundries:
    Central......................................                0                0            28,691                0           28,691           28,691
    Eastern......................................                0                0            62,646                0           62,646           62,646
    Pacific......................................                0                0             2,402                0            2,402            2,402
    Southern.....................................                0                0           187,883                0          187,883          187,883
    Western......................................                0                0            44,171                0           44,171           44,171
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0           325,794                0          325,794          325,794
Landscaping and Facilities Support:
    Central......................................                0                0           610,504                0          610,504          610,504
    Eastern......................................                0                0         1,284,623                0        1,284,623        1,284,623
    Pacific......................................                0                0            40,324                0           40,324           40,324
    Southern.....................................                0                0         3,782,727                0        3,782,727        3,782,727
    Western......................................                0                0           861,380                0          861,380          861,380
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0         6,579,558                0        6,579,558        6,579,558
Maintenance and Repair:
    Central......................................                0                0           296,626                0          296,626          296,626
    Eastern......................................                0                0           477,300                0          477,300          477,300
    Pacific......................................                0                0             9,812                0            9,812            9,812
    Southern.....................................                0                0         1,627,494                0        1,627,494        1,627,494
    Western......................................                0                0           378,264                0          378,264          378,264
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0         2,789,495                0        2,789,495        2,789,495
Manufacturing:
    Central......................................                0                0         2,815,756                0        2,815,756        2,815,756
    Eastern......................................                0                0         3,309,944                0        3,309,944        3,309,944
    Pacific......................................                0                0            17,507                0           17,507           17,507
    Southern.....................................                0                0         9,185,471                0        9,185,471        9,185,471
    Western......................................                0                0         1,892,238                0        1,892,238        1,892,238
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0        17,220,917                0       17,220,917       17,220,917
Oil and Gas:
    Central......................................                0                0            71,167                0           71,167           71,167
    Eastern......................................                0                0            43,763                0           43,763           43,763
    Southern.....................................                0                0         2,287,363                0        2,287,363        2,287,363
    Western......................................                0                0            57,779                0           57,779           57,779
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0         2,460,073                0        2,460,073        2,460,073

[[Page 70905]]

 
Postal and Delivery Services:
    Central......................................                0                0           103,744                0          103,744          103,744
    Eastern......................................                0                0           192,372                0          192,372          192,372
    Pacific......................................                0                0             3,375                0            3,375            3,375
    Southern.....................................                0                0           535,190                0          535,190          535,190
    Western......................................                0                0           138,225                0          138,225          138,225
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0           972,907                0          972,907          972,907
Recreation and Amusement:
    Central......................................                0                0           171,128                0          171,128          171,128
    Eastern......................................                0                0           349,544                0          349,544          349,544
    Pacific......................................                0                0             7,457                0            7,457            7,457
    Southern.....................................                0                0         1,169,540                0        1,169,540        1,169,540
    Western......................................                0                0           304,739                0          304,739          304,739
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0         2,002,408                0        2,002,408        2,002,408
Sanitation and Waste Removal:
    Central......................................                0                0            45,838                0           45,838           45,838
    Eastern......................................                0                0            92,339                0           92,339           92,339
    Pacific......................................                0                0             3,032                0            3,032            3,032
    Southern.....................................                0                0           295,978                0          295,978          295,978
    Western......................................                0                0            66,648                0           66,648           66,648
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0           503,834                0          503,834          503,834
Telecommunications:
    Central......................................                0                0           116,889                0          116,889          116,889
    Eastern......................................                0                0           215,275                0          215,275          215,275
    Pacific......................................                0                0             4,305                0            4,305            4,305
    Southern.....................................                0                0           674,933                0          674,933          674,933
    Western......................................                0                0           138,645                0          138,645          138,645
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0         1,150,047                0        1,150,047        1,150,047
Temporary Help Services:
    Central......................................                0                0           724,251                0          724,251          724,251
    Eastern......................................                0                0         1,296,067                0        1,296,067        1,296,067
    Pacific......................................                0                0            48,819                0           48,819           48,819
    Southern.....................................                0                0         8,228,325                0        8,228,325        8,228,325
    Western......................................                0                0         1,330,859                0        1,330,859        1,330,859
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0        11,628,319                0       11,628,319       11,628,319
Transportation:
    Central......................................                0                0           466,232                0          466,232          466,232
    Eastern......................................                0                0           554,960                0          554,960          554,960
    Pacific......................................                0                0            31,866                0           31,866           31,866
    Southern.....................................                0                0         2,752,408                0        2,752,408        2,752,408
    Western......................................                0                0           508,720                0          508,720          508,720
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0         4,314,186                0        4,314,186        4,314,186
Utilities:
    Central......................................                0                0           193,162                0          193,162          193,162
    Eastern......................................                0                0           321,518                0          321,518          321,518
    Pacific......................................                0                0             2,267                0            2,267            2,267
    Southern.....................................                0                0         1,055,740                0        1,055,740        1,055,740
    Western......................................                0                0           186,661                0          186,661          186,661
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0         1,759,348                0        1,759,348        1,759,348
Warehousing:
    Central......................................                0                0           174,882                0          174,882          174,882
    Eastern......................................                0                0           290,194                0          290,194          290,194
    Pacific......................................                0                0             1,963                0            1,963            1,963
    Southern.....................................                0                0           819,396                0          819,396          819,396
    Western......................................                0                0           217,114                0          217,114          217,114
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0         1,503,548                0        1,503,548        1,503,548
Non-Core:
    Central......................................                0                0         7,619,024                0        7,619,024        7,619,024
    Eastern......................................                0                0        16,120,110                0       16,120,110       16,120,110
    Pacific......................................                0                0           379,699                0          379,699          379,699
    Southern.....................................                0                0        31,249,924                0       31,249,924       31,249,924
    Western......................................                0                0        12,562,661                0       12,562,661       12,562,661
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0        67,931,418                0       67,931,418       67,931,418
Total Costs for Observation for Signs and
 Symptoms--Designated Person:
    Central......................................                0                0        17,543,033                0       17,543,033       17,543,033
    Eastern......................................                0                0        31,425,564                0       31,425,564       31,425,564
    Pacific......................................                0                0           773,951                0          773,951          773,951
    Southern.....................................                0                0        88,548,322                0       88,548,322       88,548,322
    Western......................................                0                0        24,843,433                0       24,843,433       24,843,433
--------------------------------------------------------------------------------------------------------------------------------------------------------

[[Page 70906]]

 
        Total....................................                0                0       163,134,305                0      163,134,305      163,134,305
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                   Observation for Signs and Symptoms--At-Risk Worker
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing:
    Central......................................                0                0           601,783                0          601,783          601,783
    Eastern......................................                0                0           437,263                0          437,263          437,263
    Pacific......................................                0                0             7,300                0            7,300            7,300
    Southern.....................................                0                0         2,241,869                0        2,241,869        2,241,869
    Western......................................                0                0           978,217                0          978,217          978,217
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0         4,266,431                0        4,266,431        4,266,431
Building Materials and Equipment Suppliers:
    Central......................................                0                0           254,972                0          254,972          254,972
    Eastern......................................                0                0           366,669                0          366,669          366,669
    Pacific......................................                0                0             9,837                0            9,837            9,837
    Southern.....................................                0                0         1,398,311                0        1,398,311        1,398,311
    Western......................................                0                0           314,304                0          314,304          314,304
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0         2,344,092                0        2,344,092        2,344,092
Commercial Kitchens:
    Central......................................                0                0         1,191,647                0        1,191,647        1,191,647
    Eastern......................................                0                0         2,100,615                0        2,100,615        2,100,615
    Pacific......................................                0                0            74,334                0           74,334           74,334
    Southern.....................................                0                0         7,309,702                0        7,309,702        7,309,702
    Western......................................                0                0         1,744,049                0        1,744,049        1,744,049
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0        12,420,346                0       12,420,346       12,420,346
Construction:
    Central......................................                0                0         3,298,568                0        3,298,568        3,298,568
    Eastern......................................                0                0         6,157,847                0        6,157,847        6,157,847
    Pacific......................................                0                0           201,444                0          201,444          201,444
    Southern.....................................                0                0        21,599,905                0       21,599,905       21,599,905
    Western......................................                0                0         4,969,725                0        4,969,725        4,969,725
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0        36,227,490                0       36,227,490       36,227,490
Drycleaning and Commercial Laundries:
    Central......................................                0                0            36,171                0           36,171           36,171
    Eastern......................................                0                0            78,978                0           78,978           78,978
    Pacific......................................                0                0             3,028                0            3,028            3,028
    Southern.....................................                0                0           236,867                0          236,867          236,867
    Western......................................                0                0            55,687                0           55,687           55,687
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0           410,732                0          410,732          410,732
Landscaping and Facilities Support:
    Central......................................                0                0           622,110                0          622,110          622,110
    Eastern......................................                0                0         1,306,100                0        1,306,100        1,306,100
    Pacific......................................                0                0            41,405                0           41,405           41,405
    Southern.....................................                0                0         3,849,145                0        3,849,145        3,849,145
    Western......................................                0                0           876,430                0          876,430          876,430
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0         6,695,191                0        6,695,191        6,695,191
Maintenance and Repair:
    Central......................................                0                0           373,959                0          373,959          373,959
    Eastern......................................                0                0           601,737                0          601,737          601,737
    Pacific......................................                0                0            12,370                0           12,370           12,370
    Southern.....................................                0                0         2,051,800                0        2,051,800        2,051,800
    Western......................................                0                0           476,882                0          476,882          476,882
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0         3,516,748                0        3,516,748        3,516,748
Manufacturing:
    Central......................................                0                0         2,952,264                0        2,952,264        2,952,264
    Eastern......................................                0                0         3,470,410                0        3,470,410        3,470,410
    Pacific......................................                0                0            18,356                0           18,356           18,356
    Southern.....................................                0                0         9,630,782                0        9,630,782        9,630,782
    Western......................................                0                0         1,983,974                0        1,983,974        1,983,974
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0        18,055,786                0       18,055,786       18,055,786
Oil and Gas:
    Central......................................                0                0            80,025                0           80,025           80,025
    Eastern......................................                0                0            49,232                0           49,232           49,232
    Southern.....................................                0                0         2,578,365                0        2,578,365        2,578,365
    Western......................................                0                0            65,098                0           65,098           65,098
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0         2,772,721                0        2,772,721        2,772,721
Postal and Delivery Services:
    Central......................................                0                0           113,937                0          113,937          113,937
    Eastern......................................                0                0           211,272                0          211,272          211,272
    Pacific......................................                0                0             3,706                0            3,706            3,706

[[Page 70907]]

 
    Southern.....................................                0                0           587,771                0          587,771          587,771
    Western......................................                0                0           151,805                0          151,805          151,805
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0         1,068,492                0        1,068,492        1,068,492
Recreation and Amusement:
    Central......................................                0                0           185,509                0          185,509          185,509
    Eastern......................................                0                0           379,348                0          379,348          379,348
    Pacific......................................                0                0             8,045                0            8,045            8,045
    Southern.....................................                0                0         1,268,180                0        1,268,180        1,268,180
    Western......................................                0                0           331,134                0          331,134          331,134
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0         2,172,216                0        2,172,216        2,172,216
Sanitation and Waste Removal:
    Central......................................                0                0            45,151                0           45,151           45,151
    Eastern......................................                0                0            90,957                0           90,957           90,957
    Pacific......................................                0                0             2,986                0            2,986            2,986
    Southern.....................................                0                0           291,545                0          291,545          291,545
    Western......................................                0                0            65,650                0           65,650           65,650
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0           496,289                0          496,289          496,289
Telecommunications:
    Central......................................                0                0           151,517                0          151,517          151,517
    Eastern......................................                0                0           279,051                0          279,051          279,051
    Pacific......................................                0                0             5,581                0            5,581            5,581
    Southern.....................................                0                0           874,884                0          874,884          874,884
    Western......................................                0                0           179,719                0          179,719          179,719
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0         1,490,753                0        1,490,753        1,490,753
Temporary Help Services:
    Central......................................                0                0           713,404                0          713,404          713,404
    Eastern......................................                0                0         1,276,657                0        1,276,657        1,276,657
    Pacific......................................                0                0            48,088                0           48,088           48,088
    Southern.....................................                0                0         8,105,101                0        8,105,101        8,105,101
    Western......................................                0                0         1,310,928                0        1,310,928        1,310,928
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0        11,454,178                0       11,454,178       11,454,178
Transportation:
    Central......................................                0                0           512,038                0          512,038          512,038
    Eastern......................................                0                0           609,483                0          609,483          609,483
    Pacific......................................                0                0            34,996                0           34,996           34,996
    Southern.....................................                0                0         3,022,823                0        3,022,823        3,022,823
    Western......................................                0                0           558,700                0          558,700          558,700
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0         4,738,041                0        4,738,041        4,738,041
Utilities:
    Central......................................                0                0           310,601                0          310,601          310,601
    Eastern......................................                0                0           516,996                0          516,996          516,996
    Pacific......................................                0                0             3,645                0            3,645            3,645
    Southern.....................................                0                0         1,697,613                0        1,697,613        1,697,613
    Western......................................                0                0           300,148                0          300,148          300,148
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0         2,829,003                0        2,829,003        2,829,003
Warehousing:
    Central......................................                0                0           192,063                0          192,063          192,063
    Eastern......................................                0                0           318,704                0          318,704          318,704
    Pacific......................................                0                0             2,156                0            2,156            2,156
    Southern.....................................                0                0           899,899                0          899,899          899,899
    Western......................................                0                0           238,445                0          238,445          238,445
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0         1,651,267                0        1,651,267        1,651,267
Non-Core:
    Central......................................                0                0         9,855,541                0        9,855,541        9,855,541
    Eastern......................................                0                0        21,006,382                0       21,006,382       21,006,382
    Pacific......................................                0                0           487,706                0          487,706          487,706
    Southern.....................................                0                0        39,335,004                0       39,335,004       39,335,004
    Western......................................                0                0        16,443,906                0       16,443,906       16,443,906
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0        87,128,538                0       87,128,538       87,128,538
Total Costs for Observation for Signs and
 Symptoms--At-Risk Worker:
    Central......................................                0                0        21,491,261                0       21,491,261       21,491,261
    Eastern......................................                0                0        39,257,702                0       39,257,702       39,257,702
    Pacific......................................                0                0           964,984                0          964,984          964,984
    Southern.....................................                0                0       106,979,565                0      106,979,565      106,979,565
    Western......................................                0                0        31,044,802                0       31,044,802       31,044,802
                                                  ------------------------------------------------------------------------------------------------------
        Total....................................                0                0       199,738,313                0      199,738,313      199,738,313
--------------------------------------------------------------------------------------------------------------------------------------------------------

[[Page 70908]]

 
                                                            Initial Hazard Alert--Supervisor
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing:
    Central......................................                0                0            71,187                0           71,187           71,187
    Eastern......................................                0                0            38,887                0           38,887           38,887
    Pacific......................................                0                0               525                0              525              525
    Southern.....................................                0                0            67,550                0           67,550           67,550
    Western......................................                0                0            23,579                0           23,579           23,579
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0           201,728                0          201,728          201,728
Building Materials and Equipment Suppliers:
    Central......................................                0                0             8,975                0            8,975            8,975
    Eastern......................................                0                0            13,148                0           13,148           13,148
    Pacific......................................                0                0               215                0              215              215
    Southern.....................................                0                0            12,095                0           12,095           12,095
    Western......................................                0                0             8,884                0            8,884            8,884
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0            43,316                0           43,316           43,316
Commercial Kitchens:
    Central......................................                0                0            67,932                0           67,932           67,932
    Eastern......................................                0                0           113,247                0          113,247          113,247
    Pacific......................................                0                0             2,165                0            2,165            2,165
    Southern.....................................                0                0            83,089                0           83,089           83,089
    Western......................................                0                0            71,282                0           71,282           71,282
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0           337,715                0          337,715          337,715
Construction:
    Central......................................                0                0            94,901                0           94,901           94,901
    Eastern......................................                0                0           139,158                0          139,158          139,158
    Pacific......................................                0                0             2,136                0            2,136            2,136
    Southern.....................................                0                0           103,318                0          103,318          103,318
    Western......................................                0                0            55,542                0           55,542           55,542
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0           395,055                0          395,055          395,055
Drycleaning and Commercial Laundries:
    Central......................................                0                0             5,638                0            5,638            5,638
    Eastern......................................                0                0            14,483                0           14,483           14,483
    Pacific......................................                0                0               114                0              114              114
    Southern.....................................                0                0             8,547                0            8,547            8,547
    Western......................................                0                0             6,139                0            6,139            6,139
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0            34,922                0           34,922           34,922
Landscaping and Facilities Support:
    Central......................................                0                0            30,364                0           30,364           30,364
    Eastern......................................                0                0            49,428                0           49,428           49,428
    Pacific......................................                0                0               719                0              719              719
    Southern.....................................                0                0            34,796                0           34,796           34,796
    Western......................................                0                0            30,665                0           30,665           30,665
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0           145,973                0          145,973          145,973
Maintenance and Repair:
    Central......................................                0                0            49,834                0           49,834           49,834
    Eastern......................................                0                0            66,053                0           66,053           66,053
    Pacific......................................                0                0               794                0              794              794
    Southern.....................................                0                0            53,651                0           53,651           53,651
    Western......................................                0                0            42,009                0           42,009           42,009
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0           212,341                0          212,341          212,341
Manufacturing:
    Central......................................                0                0            18,064                0           18,064           18,064
    Eastern......................................                0                0            20,957                0           20,957           20,957
    Pacific......................................                0                0               167                0              167              167
    Southern.....................................                0                0            15,718                0           15,718           15,718
    Western......................................                0                0            14,869                0           14,869           14,869
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0            69,774                0           69,774           69,774
Oil and Gas:
    Central......................................                0                0            12,981                0           12,981           12,981
    Eastern......................................                0                0             6,913                0            6,913            6,913
    Southern.....................................                0                0                 0                0                0                0
    Western......................................                0                0            47,995                0           47,995           47,995
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0             6,619                0            6,619            6,619
Postal and Delivery Services:
    Central......................................                0                0            24,791                0           24,791           24,791
    Eastern......................................                0                0            31,359                0           31,359           31,359
    Pacific......................................                0                0               331                0              331              331
    Southern.....................................                0                0            23,087                0           23,087           23,087
    Western......................................                0                0            14,795                0           14,795           14,795
                                                  ------------------------------------------------------------------------------------------------------

[[Page 70909]]

 
        Subtotal.................................                0                0            94,363                0           94,363           94,363
Recreation and Amusement:
    Central......................................                0                0            20,673                0           20,673           20,673
    Eastern......................................                0                0            31,001                0           31,001           31,001
    Pacific......................................                0                0               389                0              389              389
    Southern.....................................                0                0            20,185                0           20,185           20,185
    Western......................................                0                0            17,180                0           17,180           17,180
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0            89,428                0           89,428           89,428
Sanitation and Waste Removal:
    Central......................................                0                0             1,900                0            1,900            1,900
    Eastern......................................                0                0             2,742                0            2,742            2,742
    Pacific......................................                0                0                42                0               42               42
    Southern.....................................                0                0             1,990                0            1,990            1,990
    Western......................................                0                0             1,343                0            1,343            1,343
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0             8,016                0            8,016            8,016
Telecommunications:
    Central......................................                0                0             6,853                0            6,853            6,853
    Eastern......................................                0                0             9,379                0            9,379            9,379
    Pacific......................................                0                0               102                0              102              102
    Southern.....................................                0                0             8,239                0            8,239            8,239
    Western......................................                0                0             5,748                0            5,748            5,748
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0            30,322                0           30,322           30,322
Temporary Help Services:
    Central......................................                0                0             3,784                0            3,784            3,784
    Eastern......................................                0                0             5,332                0            5,332            5,332
    Pacific......................................                0                0                51                0               51               51
    Southern.....................................                0                0             4,527                0            4,527            4,527
    Western......................................                0                0             3,253                0            3,253            3,253
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0            16,947                0           16,947           16,947
Transportation:
    Central......................................                0                0            99,748                0           99,748           99,748
    Eastern......................................                0                0            89,795                0           89,795           89,795
    Pacific......................................                0                0             1,119                0            1,119            1,119
    Southern.....................................                0                0            91,342                0           91,342           91,342
    Western......................................                0                0            35,838                0           35,838           35,838
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0           317,842                0          317,842          317,842
Utilities:
    Central......................................                0                0            16,409                0           16,409           16,409
    Eastern......................................                0                0            20,570                0           20,570           20,570
    Pacific......................................                0                0               141                0              141              141
    Southern.....................................                0                0            23,071                0           23,071           23,071
    Western......................................                0                0            11,751                0           11,751           11,751
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0            71,942                0           71,942           71,942
Warehousing:
    Central......................................                0                0             8,066                0            8,066            8,066
    Eastern......................................                0                0            10,200                0           10,200           10,200
    Pacific......................................                0                0               129                0              129              129
    Southern.....................................                0                0            10,013                0           10,013           10,013
    Western......................................                0                0             7,574                0            7,574            7,574
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0            35,982                0           35,982           35,982
Non-Core:
    Central......................................                0                0           781,190                0          781,190          781,190
    Eastern......................................                0                0         1,221,415                0        1,221,415        1,221,415
    Pacific......................................                0                0            18,719                0           18,719           18,719
    Southern.....................................                0                0           969,956                0          969,956          969,956
    Western......................................                0                0           778,728                0          778,728          778,728
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0         3,770,009                0        3,770,009        3,770,009
Total Costs for Initial Hazard Alert--Supervisor:
    Central......................................                0                0         1,323,291                0        1,323,291        1,323,291
    Eastern......................................                0                0         1,884,066                0        1,884,066        1,884,066
    Pacific......................................                0                0            27,858                0           27,858           27,858
    Southern.....................................                0                0         1,579,170                0        1,579,170        1,579,170
    Western......................................                0                0         1,135,797                0        1,135,797        1,135,797
                                                  ------------------------------------------------------------------------------------------------------
        Total....................................                0                0         5,950,182                0        5,950,182        5,950,182
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                           Subsequent Hazard Alert--Supervisor
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing:
    Central......................................                0                0           149,209                0          149,209          149,209
    Eastern......................................                0                0            88,960                0           88,960           88,960

[[Page 70910]]

 
    Pacific......................................                0                0             1,530                0            1,530            1,530
    Southern.....................................                0                0           568,001                0          568,001          568,001
    Western......................................                0                0            38,555                0           38,555           38,555
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0           846,254                0          846,254          846,254
Building Materials and Equipment Suppliers:
    Central......................................                0                0            16,253                0           16,253           16,253
    Eastern......................................                0                0            25,292                0           25,292           25,292
    Pacific......................................                0                0               626                0              626              626
    Southern.....................................                0                0           115,252                0          115,252          115,252
    Western......................................                0                0            24,002                0           24,002           24,002
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0           181,424                0          181,424          181,424
Commercial Kitchens:
    Central......................................                0                0           120,142                0          120,142          120,142
    Eastern......................................                0                0           218,769                0          218,769          218,769
    Pacific......................................                0                0             6,307                0            6,307            6,307
    Southern.....................................                0                0           781,907                0          781,907          781,907
    Western......................................                0                0           195,280                0          195,280          195,280
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0         1,322,405                0        1,322,405        1,322,405
Construction:
    Central......................................                0                0           164,418                0          164,418          164,418
    Eastern......................................                0                0           279,925                0          279,925          279,925
    Pacific......................................                0                0             6,223                0            6,223            6,223
    Southern.....................................                0                0           990,737                0          990,737          990,737
    Western......................................                0                0           131,620                0          131,620          131,620
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0         1,572,922                0        1,572,922        1,572,922
Drycleaning and Commercial Laundries:
    Central......................................                0                0            10,046                0           10,046           10,046
    Eastern......................................                0                0            26,309                0           26,309           26,309
    Pacific......................................                0                0               332                0              332              332
    Southern.....................................                0                0            80,016                0           80,016           80,016
    Western......................................                0                0            17,282                0           17,282           17,282
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0           133,985                0          133,985          133,985
Landscaping and Facilities Support:
    Central......................................                0                0            54,037                0           54,037           54,037
    Eastern......................................                0                0            98,530                0           98,530           98,530
    Pacific......................................                0                0             2,096                0            2,096            2,096
    Southern.....................................                0                0           336,231                0          336,231          336,231
    Western......................................                0                0            84,009                0           84,009           84,009
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0           574,904                0          574,904          574,904
Maintenance and Repair:
    Central......................................                0                0            88,347                0           88,347           88,347
    Eastern......................................                0                0           132,539                0          132,539          132,539
    Pacific......................................                0                0             2,313                0            2,313            2,313
    Southern.....................................                0                0           506,615                0          506,615          506,615
    Western......................................                0                0           115,861                0          115,861          115,861
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0           845,675                0          845,675          845,675
Manufacturing:
    Central......................................                0                0            30,252                0           30,252           30,252
    Eastern......................................                0                0            39,098                0           39,098           39,098
    Pacific......................................                0                0               487                0              487              487
    Southern.....................................                0                0           141,837                0          141,837          141,837
    Western......................................                0                0            39,037                0           39,037           39,037
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0           250,711                0          250,711          250,711
Oil and Gas:
    Central......................................                0                0            26,387                0           26,387           26,387
    Eastern......................................                0                0            10,013                0           10,013           10,013
    Southern.....................................                0                0           420,050                0          420,050          420,050
    Western......................................                0                0            11,239                0           11,239           11,239
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0           467,689                0          467,689          467,689
Postal and Delivery Services:
    Central......................................                0                0            47,695                0           47,695           47,695
    Eastern......................................                0                0            58,857                0           58,857           58,857
    Pacific......................................                0                0               965                0              965              965
    Southern.....................................                0                0           194,296                0          194,296          194,296
    Western......................................                0                0            37,304                0           37,304           37,304
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0           339,116                0          339,116          339,116
Recreation and Amusement:
    Central......................................                0                0            35,170                0           35,170           35,170
    Eastern......................................                0                0            60,614                0           60,614           60,614

[[Page 70911]]

 
    Pacific......................................                0                0             1,133                0            1,133            1,133
    Southern.....................................                0                0           188,542                0          188,542          188,542
    Western......................................                0                0            44,903                0           44,903           44,903
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0           330,363                0          330,363          330,363
Sanitation and Waste Removal:
    Central......................................                0                0             3,271                0            3,271            3,271
    Eastern......................................                0                0             5,309                0            5,309            5,309
    Pacific......................................                0                0               121                0              121              121
    Southern.....................................                0                0            18,021                0           18,021           18,021
    Western......................................                0                0             3,586                0            3,586            3,586
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0            30,308                0           30,308           30,308
Telecommunications:
    Central......................................                0                0            12,587                0           12,587           12,587
    Eastern......................................                0                0            19,110                0           19,110           19,110
    Pacific......................................                0                0               298                0              298              298
    Southern.....................................                0                0            73,609                0           73,609           73,609
    Western......................................                0                0            15,550                0           15,550           15,550
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0           121,154                0          121,154          121,154
Temporary Help Services:
    Central......................................                0                0             6,407                0            6,407            6,407
    Eastern......................................                0                0            11,059                0           11,059           11,059
    Pacific......................................                0                0               149                0              149              149
    Southern.....................................                0                0            41,583                0           41,583           41,583
    Western......................................                0                0             9,367                0            9,367            9,367
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0            68,566                0           68,566           68,566
Transportation:
    Central......................................                0                0           184,544                0          184,544          184,544
    Eastern......................................                0                0           184,968                0          184,968          184,968
    Pacific......................................                0                0             3,259                0            3,259            3,259
    Southern.....................................                0                0           842,960                0          842,960          842,960
    Western......................................                0                0            83,587                0           83,587           83,587
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0         1,299,318                0        1,299,318        1,299,318
Utilities:
    Central......................................                0                0            30,683                0           30,683           30,683
    Eastern......................................                0                0            44,025                0           44,025           44,025
    Pacific......................................                0                0               411                0              411              411
    Southern.....................................                0                0           201,775                0          201,775          201,775
    Western......................................                0                0            29,334                0           29,334           29,334
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0           306,228                0          306,228          306,228
Warehousing:
    Central......................................                0                0            15,139                0           15,139           15,139
    Eastern......................................                0                0            22,380                0           22,380           22,380
    Pacific......................................                0                0               377                0              377              377
    Southern.....................................                0                0            87,373                0           87,373           87,373
    Western......................................                0                0            21,292                0           21,292           21,292
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0           146,561                0          146,561          146,561
Non-Core:
    Central......................................                0                0         1,389,956                0        1,389,956        1,389,956
    Eastern......................................                0                0         2,433,884                0        2,433,884        2,433,884
    Pacific......................................                0                0            54,538                0           54,538           54,538
    Southern.....................................                0                0         9,127,069                0        9,127,069        9,127,069
    Western......................................                0                0         2,149,829                0        2,149,829        2,149,829
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0        15,155,276                0       15,155,276       15,155,276
Total Costs for Subsequent Hazard Alert--
 Supervisor:
    Central......................................                0                0         2,384,543                0        2,384,543        2,384,543
    Eastern......................................                0                0         3,759,640                0        3,759,640        3,759,640
    Pacific......................................                0                0            81,165                0           81,165           81,165
    Southern.....................................                0                0        14,715,873                0       14,715,873       14,715,873
    Western......................................                0                0         3,051,637                0        3,051,637        3,051,637
                                                  ------------------------------------------------------------------------------------------------------
        Total....................................                0                0        23,992,858                0       23,992,858       23,992,858
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                      Warning Signs
--------------------------------------------------------------------------------------------------------------------------------------------------------
Commercial Kitchens:
    Alaskan......................................              564              627                 0                0              564              627
    Central......................................           44,703           49,766                 0                0           44,703           49,766
    Eastern......................................           77,765           86,573                 0                0           77,765           86,573
    Pacific......................................            1,463            1,629                 0                0            1,463            1,629
    Southern.....................................           57,794           64,340                 0                0           57,794           64,340

[[Page 70912]]

 
    Western......................................           49,059           54,616                 0                0           49,059           54,616
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................          231,347          257,551                 0                0          231,347          257,551
Construction:
    Alaskan......................................              151              168                 0                0              151              168
    Central......................................           10,082           11,224                 0                0           10,082           11,224
    Eastern......................................           16,073           17,893                 0                0           16,073           17,893
    Pacific......................................              257              286                 0                0              257              286
    Southern.....................................           12,900           14,361                 0                0           12,900           14,361
    Western......................................            6,793            7,563                 0                0            6,793            7,563
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................           46,255           51,494                 0                0           46,255           51,494
Drycleaning and Commercial Laundries:
    Alaskan......................................               20               22                 0                0               20               22
    Central......................................            2,516            2,801                 0                0            2,516            2,801
    Eastern......................................            6,463            7,195                 0                0            6,463            7,195
    Pacific......................................               51               57                 0                0               51               57
    Southern.....................................            3,814            4,246                 0                0            3,814            4,246
    Western......................................            2,740            3,050                 0                0            2,740            3,050
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................           15,604           17,371                 0                0           15,604           17,371
Landscaping and Facilities Support:
    Alaskan......................................               11               12                 0                0               11               12
    Central......................................            2,626            2,924                 0                0            2,626            2,924
    Eastern......................................            3,808            4,239                 0                0            3,808            4,239
    Pacific......................................               18               20                 0                0               18               20
    Southern.....................................            2,320            2,583                 0                0            2,320            2,583
    Western......................................              939            1,046                 0                0              939            1,046
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................            9,722           10,824                 0                0            9,722           10,824
Maintenance and Repair:
    Alaskan......................................               40               44                 0                0               40               44
    Central......................................            2,629            2,927                 0                0            2,629            2,927
    Eastern......................................            2,729            3,038                 0                0            2,729            3,038
    Pacific......................................               39               44                 0                0               39               44
    Southern.....................................            2,972            3,309                 0                0            2,972            3,309
    Western......................................            1,688            1,879                 0                0            1,688            1,879
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................           10,097           11,240                 0                0           10,097           11,240
Manufacturing:
    Alaskan......................................               13               14                 0                0               13               14
    Central......................................            3,739            4,162                 0                0            3,739            4,162
    Eastern......................................            4,182            4,656                 0                0            4,182            4,656
    Pacific......................................               28               32                 0                0               28               32
    Southern.....................................            3,298            3,672                 0                0            3,298            3,672
    Western......................................            2,854            3,177                 0                0            2,854            3,177
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................           14,114           15,713                 0                0           14,114           15,713
Oil and Gas:
    Alaskan......................................               10               11                 0                0               10               11
    Central......................................              736              819                 0                0              736              819
    Eastern......................................              499              555                 0                0              499              555
    Southern.....................................            1,582            1,761                 0                0            1,582            1,761
    Western......................................              253              281                 0                0              253              281
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................            3,079            3,428                 0                0            3,079            3,428
Transportation:
    Alaskan......................................               20               23                 0                0               20               23
    Central......................................               56               63                 0                0               56               63
    Eastern......................................              137              153                 0                0              137              153
    Pacific......................................                5                6                 0                0                5                6
    Southern.....................................              208              231                 0                0              208              231
    Western......................................               55               62                 0                0               55               62
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................              482              536                 0                0              482              536
Utilities:
    Alaskan......................................               79               88                 0                0               79               88
    Central......................................            2,710            3,017                 0                0            2,710            3,017
    Eastern......................................            3,593            4,000                 0                0            3,593            4,000
    Pacific......................................                3                3                 0                0                3                3
    Southern.....................................            3,300            3,673                 0                0            3,300            3,673
    Western......................................            1,554            1,730                 0                0            1,554            1,730
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................           11,240           12,513                 0                0           11,240           12,513
Non-Core:
    Alaskan......................................                8                9                 0                0                8                9
    Central......................................              681              758                 0                0              681              758
    Eastern......................................            1,759            1,958                 0                0            1,759            1,958
    Pacific......................................               19               22                 0                0               19               22

[[Page 70913]]

 
    Southern.....................................              804              895                 0                0              804              895
    Western......................................            1,388            1,546                 0                0            1,388            1,546
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................            4,659            5,187                 0                0            4,659            5,187
Total Costs for Warning Signs:
    Alaskan......................................              915            1,019                 0                0              915            1,019
    Central......................................           70,478           78,460                 0                0           70,478           78,460
    Eastern......................................          117,007          130,260                 0                0          117,007          130,260
    Pacific......................................            1,884            2,098                 0                0            1,884            2,098
    Southern.....................................           88,991           99,071                 0                0           88,991           99,071
    Western......................................           67,324           74,949                 0                0           67,324           74,949
        Total....................................          346,599          385,857                 0                0          346,599          385,857
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                    Signage Placement
--------------------------------------------------------------------------------------------------------------------------------------------------------
Commercial Kitchens:
    Alaskan......................................              116              129                 0                0              116              129
    Central......................................            9,215           10,259                 0                0            9,215           10,259
    Eastern......................................           16,044           17,862                 0                0           16,044           17,862
    Pacific......................................              303              337                 0                0              303              337
    Southern.....................................           11,913           13,262                 0                0           11,913           13,262
    Western......................................           10,122           11,268                 0                0           10,122           11,268
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................           47,714           53,118                 0                0           47,714           53,118
Construction:
    Alaskan......................................               73               82                 0                0               73               82
    Central......................................            4,761            5,301                 0                0            4,761            5,301
    Eastern......................................            7,589            8,449                 0                0            7,589            8,449
    Pacific......................................              125              139                 0                0              125              139
    Southern.....................................            6,167            6,866                 0                0            6,167            6,866
    Western......................................            3,500            3,896                 0                0            3,500            3,896
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................           22,216           24,732                 0                0           22,216           24,732
Drycleaning and Commercial Laundries:
    Alaskan......................................                7                8                 0                0                7                8
    Central......................................              846              941                 0                0              846              941
    Eastern......................................            2,172            2,419                 0                0            2,172            2,419
    Pacific......................................               17               19                 0                0               17               19
    Southern.....................................            1,282            1,427                 0                0            1,282            1,427
    Western......................................              921            1,025                 0                0              921            1,025
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................            5,245            5,839                 0                0            5,245            5,839
Landscaping and Facilities Support:
    Alaskan......................................                4                4                 0                0                4                4
    Central......................................              883              983                 0                0              883              983
    Eastern......................................            1,280            1,425                 0                0            1,280            1,425
    Pacific......................................                6                7                 0                0                6                7
    Southern.....................................              780              868                 0                0              780              868
    Western......................................              316              352                 0                0              316              352
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................            3,268            3,638                 0                0            3,268            3,638
Maintenance and Repair:
    Alaskan......................................               13               15                 0                0               13               15
    Central......................................              884              984                 0                0              884              984
    Eastern......................................              917            1,021                 0                0              917            1,021
    Pacific......................................               13               15                 0                0               13               15
    Southern.....................................              999            1,112                 0                0              999            1,112
    Western......................................              567              632                 0                0              567              632
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................            3,394            3,778                 0                0            3,394            3,778
Manufacturing:
    Alaskan......................................                6                6                 0                0                6                6
    Central......................................            1,615            1,798                 0                0            1,615            1,798
    Eastern......................................            1,806            2,011                 0                0            1,806            2,011
    Pacific......................................               12               14                 0                0               12               14
    Southern.....................................            1,425            1,586                 0                0            1,425            1,586
    Western......................................            1,233            1,372                 0                0            1,233            1,372
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................            6,096            6,787                 0                0            6,096            6,787
Oil and Gas:
    Alaskan......................................                4                4                 0                0                4                4
    Central......................................              275              306                 0                0              275              306
    Eastern......................................              187              208                 0                0              187              208
    Southern.....................................              592              659                 0                0              592              659
    Western......................................               95              105                 0                0               95              105
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................            1,152            1,282                 0                0            1,152            1,282
Transportation:
    Alaskan......................................                8                9                 0                0                8                9

[[Page 70914]]

 
    Central......................................               21               23                 0                0               21               23
    Eastern......................................               51               57                 0                0               51               57
    Pacific......................................                2                2                 0                0                2                2
    Southern.....................................               78               86                 0                0               78               86
    Western......................................               21               23                 0                0               21               23
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................              180              201                 0                0              180              201
Utilities:
    Alaskan......................................               46               51                 0                0               46               51
    Central......................................            1,572            1,750                 0                0            1,572            1,750
    Eastern......................................            2,084            2,320                 0                0            2,084            2,320
    Pacific......................................                2                2                 0                0                2                2
    Southern.....................................            1,914            2,130                 0                0            1,914            2,130
    Western......................................              901            1,003                 0                0              901            1,003
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................            6,518            7,256                 0                0            6,518            7,256
Non-Core:
    Alaskan......................................                5                5                 0                0                5                5
    Central......................................              402              448                 0                0              402              448
    Eastern......................................            1,039            1,156                 0                0            1,039            1,156
    Pacific......................................               11               13                 0                0               11               13
    Southern.....................................              475              528                 0                0              475              528
    Western......................................              820              913                 0                0              820              913
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................            2,751            3,063                 0                0            2,751            3,063
Total Costs for Signage Placement:
    Alaskan......................................              281              312                 0                0              281              312
    Central......................................           20,474           22,793                 0                0           20,474           22,793
    Eastern......................................           33,170           36,927                 0                0           33,170           36,927
    Pacific......................................              492              547                 0                0              492              547
    Southern.....................................           25,623           28,525                 0                0           25,623           28,525
    Western......................................           18,495           20,590                 0                0           18,495           20,590
        Total....................................           98,534          109,694                 0                0           98,534          109,694
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                             Total Costs for Requirements at or above the High Heat Trigger
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing:
    Central......................................                0                0        42,380,008       28,260,379       14,119,630       14,119,630
    Eastern......................................                0                0        35,661,233       23,886,065       11,775,168       11,775,168
    Pacific......................................                0                0           556,114          371,868          184,245          184,245
    Southern.....................................                0                0       192,037,096      128,848,517       63,188,579       63,188,579
    Western......................................                0                0        27,352,262       17,612,811        9,739,451        9,739,451
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0       297,986,712      198,979,639       99,007,073       99,007,073
Building Materials and Equipment Suppliers:
    Central......................................                0                0        15,259,345       10,720,490        4,538,855        4,538,855
    Eastern......................................                0                0        27,374,501       19,326,690        8,047,810        8,047,810
    Pacific......................................                0                0           695,315          489,955          205,360          205,360
    Southern.....................................                0                0       114,088,707       80,616,258       33,472,449       33,472,449
    Western......................................                0                0        10,537,593        7,222,675        3,314,918        3,314,918
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0       167,955,460      118,376,068       49,579,392       49,579,392
Commercial Kitchens:
    Alaskan......................................              680              757                 0                0              680              757
    Central......................................           53,918           60,025        68,619,433       50,009,739       18,663,611       18,669,718
    Eastern......................................           93,809          104,434       151,155,901      110,815,642       40,434,069       40,444,694
    Pacific......................................            1,767            1,967         5,006,642        3,663,797        1,344,612        1,344,812
    Southern.....................................           69,707           77,602       573,330,985      421,490,458      151,910,234      151,918,129
    Western......................................           59,181           65,884        60,628,710       43,350,035       17,337,856       17,344,559
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................          279,061          310,669       858,741,671      629,329,670      229,691,061      229,722,669
Construction:
    Alaskan......................................              224              249                 0                0              224              249
    Central......................................           14,843           16,524       209,056,982      141,690,442       67,381,383       67,383,064
    Eastern......................................           23,662           26,342       463,946,432      316,103,585      147,866,509      147,869,189
    Pacific......................................              382              425        14,776,247       10,040,905        4,735,724        4,735,767
    Southern.....................................           19,067           21,226     1,826,423,948    1,246,717,469      579,725,546      579,727,706
    Western......................................           10,293           11,459       193,613,925      129,218,140       64,406,078       64,407,244
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................           68,470           76,226     2,707,817,534    1,843,770,540      864,115,464      864,123,220
Drycleaning and Commercial Laundries:
    Alaskan......................................               27               30                 0                0               27               30
    Central......................................            3,362            3,742         2,128,940        1,511,252          621,050          621,431
    Eastern......................................            8,636            9,614         5,791,351        4,134,982        1,665,005        1,665,983
    Pacific......................................               68               76           208,637          149,402           59,303           59,311
    Southern.....................................            5,096            5,674        19,050,617       13,664,133        5,391,581        5,392,158
    Western......................................            3,660            4,075         1,935,742        1,341,209          598,194          598,608
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................           20,849           23,210        29,115,287       20,800,977        8,335,159        8,337,520

[[Page 70915]]

 
Landscaping and Facilities Support:
    Alaskan......................................               14               16                 0                0               14               16
    Central......................................            3,509            3,907        38,297,610       25,669,779       12,631,341       12,631,739
    Eastern......................................            5,088            5,664        99,438,739       67,109,986       32,333,840       32,334,416
    Pacific......................................               24               27         3,040,514        2,046,991          993,547          993,550
    Southern.....................................            3,100            3,451       327,823,997      221,913,360      105,913,738      105,914,089
    Western......................................            1,255            1,397        33,798,576       22,246,099       11,553,732       11,553,874
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................           12,990           14,462       502,399,436      338,986,214      163,426,212      163,427,683
Maintenance and Repair:
    Alaskan......................................               53               59                 0                0               53               59
    Central......................................            3,513            3,911        23,017,823       15,941,193        7,080,143        7,080,541
    Eastern......................................            3,646            4,059        45,127,748       31,452,400       13,678,994       13,679,407
    Pacific......................................               53               59           887,136          617,516          269,672          269,678
    Southern.....................................            3,971            4,421       169,223,833      118,399,919       50,827,885       50,828,335
    Western......................................            2,255            2,511        17,659,435       11,977,449        5,684,241        5,684,496
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................           13,491           15,019       255,915,975      178,388,478       77,540,988       77,542,516
Manufacturing:
    Alaskan......................................               18               20                 0                0               18               20
    Central......................................            5,353            5,960       183,678,416      132,203,016       51,480,754       51,481,360
    Eastern......................................            5,989            6,667       265,045,610      191,654,507       73,397,092       73,397,770
    Pacific......................................               41               45         1,255,989          900,119          355,911          355,916
    Southern.....................................            4,723            5,258       765,527,687      553,306,520      212,225,890      212,226,425
    Western......................................            4,087            4,550        62,524,352       43,702,341       18,826,098       18,826,561
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................           20,211           22,500     1,278,032,055      921,766,502      356,285,763      356,288,052
Oil and Gas:
    Alaskan......................................               14               16                 0                0               14               16
    Central......................................            1,011            1,125         4,844,875        3,255,669        1,590,217        1,590,331
    Eastern......................................              685              763         3,957,224        2,687,559        1,270,351        1,270,429
    Southern.....................................            2,173            2,419       219,150,051      149,263,297       69,888,927       69,889,173
    Western......................................              347              387         2,790,653        1,855,780          935,221          935,260
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................            4,231            4,710       230,742,803      157,062,304       73,684,730       73,685,209
Postal and Delivery Services:
    Central......................................                0                0         7,067,739        4,865,313        2,202,426        2,202,426
    Eastern......................................                0                0        15,795,086       10,979,919        4,815,167        4,815,167
    Pacific......................................                0                0           259,654          179,937           79,717           79,717
    Southern.....................................                0                0        48,615,830       33,929,834       14,685,996       14,685,996
    Western......................................                0                0         5,333,758        3,598,956        1,734,802        1,734,802
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0        77,072,067       53,553,958       23,518,109       23,518,109
Recreation and Amusement:
    Central......................................                0                0        11,449,963        7,788,056        3,661,907        3,661,907
    Eastern......................................                0                0        29,020,353       19,883,004        9,137,349        9,137,349
    Pacific......................................                0                0           577,712          395,164          182,548          182,548
    Southern.....................................                0                0       106,664,237       73,343,696       33,320,541       33,320,541
    Western......................................                0                0        12,200,093        8,139,672        4,060,421        4,060,421
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0       159,912,358      109,549,593       50,362,765       50,362,765
Sanitation and Waste Removal:
    Central......................................                0                0         2,772,688        1,898,218          874,470          874,470
    Eastern......................................                0                0         6,804,557        4,677,890        2,126,667        2,126,667
    Pacific......................................                0                0           215,690          148,006           67,684           67,684
    Southern.....................................                0                0        24,349,088       16,796,017        7,553,071        7,553,071
    Western......................................                0                0         2,307,226        1,543,819          763,407          763,407
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0        36,449,250       25,063,950       11,385,300       11,385,300
Telecommunications:
    Central......................................                0                0         9,176,182        6,378,212        2,797,971        2,797,971
    Eastern......................................                0                0        21,179,000       14,811,293        6,367,707        6,367,707
    Pacific......................................                0                0           388,366          270,956          117,410          117,410
    Southern.....................................                0                0        72,117,556       50,535,718       21,581,839       21,581,839
    Western......................................                0                0         6,987,064        4,781,573        2,205,491        2,205,491
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0       109,848,169       76,777,752       33,070,417       33,070,417
Temporary Help Services:
    Central......................................                0                0        39,694,731       27,884,466       11,810,265       11,810,265
    Eastern......................................                0                0        96,536,678       68,420,422       28,116,256       28,116,256
    Pacific......................................                0                0         3,309,799        2,338,558          971,241          971,241
    Southern.....................................                0                0       660,310,207      468,920,086      191,390,121      191,390,121
    Western......................................                0                0        46,479,235       32,035,820       14,443,415       14,443,415
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0       846,330,650      599,599,352      246,731,298      246,731,298
Transportation:
    Alaskan......................................               28               31                 0                0               28               31
    Central......................................               77               86        32,003,351       21,724,453       10,278,975       10,278,984
    Eastern......................................              188              210        47,422,875       32,486,839       14,936,225       14,936,247

[[Page 70916]]

 
    Pacific......................................                7                8         2,524,644        1,730,353          794,298          794,299
    Southern.....................................              285              318       253,695,845      174,399,675       79,296,456       79,296,488
    Western......................................               76               85        22,541,484       15,127,338        7,414,223        7,414,231
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................              662              737       358,188,201      245,468,657      112,720,205      112,720,280
Utilities:
    Alaskan......................................              125              139                 0                0              125              139
    Central......................................            4,282            4,767        19,601,649       13,433,591        6,172,340        6,172,825
    Eastern......................................            5,677            6,320        39,556,812       27,238,766       12,323,724       12,324,367
    Pacific......................................                5                5           281,923          194,078           87,850           87,850
    Southern.....................................            5,213            5,804       141,846,798       97,848,768       44,003,243       44,003,834
    Western......................................            2,455            2,734        11,600,777        7,829,182        3,774,051        3,774,329
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................           17,758           19,769       212,887,959      146,544,384       66,361,333       66,363,344
Warehousing:
    Central......................................                0                0        11,386,839        8,060,758        3,326,081        3,326,081
    Eastern......................................                0                0        23,769,417       16,940,032        6,829,384        6,829,384
    Pacific......................................                0                0           150,530          106,818           43,711           43,711
    Southern.....................................                0                0        72,652,817       51,878,587       20,774,229       20,774,229
    Western......................................                0                0         7,971,638        5,506,470        2,465,168        2,465,168
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................                0                0       115,931,240       82,492,666       33,438,574       33,438,574
Non-Core:
    Alaskan......................................               13               14                 0                0               13               14
    Central......................................            1,083            1,206       569,939,859      395,235,676      174,705,267      174,705,390
    Eastern......................................            2,798            3,114     1,571,729,282    1,094,641,235      477,090,844      477,091,161
    Pacific......................................               31               34        34,448,756       23,901,214       10,547,573       10,547,576
    Southern.....................................            1,278            1,423     3,222,640,561    2,265,794,085      956,847,754      956,847,899
    Western......................................            2,208            2,458       578,369,859      391,910,093      186,461,974      186,462,224
                                                  ------------------------------------------------------------------------------------------------------
        Subtotal.................................            7,410            8,250     5,977,128,316    4,171,482,302    1,805,653,424    1,805,654,264
Total:
    Alaskan......................................            1,196            1,331                 0                0            1,196            1,331
    Central......................................           90,952          101,253     1,290,376,435      896,530,702      393,936,685      393,946,986
    Eastern......................................          150,177          167,187     2,949,312,800    2,057,250,816      892,212,161      892,229,171
    Pacific......................................            2,376            2,645        68,583,668       47,545,638       21,040,406       21,040,676
    Southern.....................................          114,614          127,596     8,809,549,859    6,167,666,393    2,641,998,079    2,642,011,061
    Western......................................           85,819           95,539     1,104,632,382      748,999,461      355,718,740      355,728,460
                                                  ------------------------------------------------------------------------------------------------------
        Total....................................          445,133          495,551    14,222,455,144    9,917,993,009    4,304,907,268    4,304,957,686
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source: OSHA estimate.
Note: Due to rounding, figures in the columns and rows may not sum to the totals shown.

F. Heat Illness and Emergency Response and Planning
    All covered employers would be required to respond when employees 
are experiencing signs and symptoms of heat-related illness or when 
there is a heat-related emergency at their work sites.
    OSHA calculates the total costs associated with responding to heat-
related illnesses by multiplying the labor-based unit cost by the 
number of affected establishments and the number of heat-related 
illnesses per establishment (shown in table VIII.C.6.).
    OSHA calculates the total costs associated with responding to heat-
related emergencies as a sum of total labor-based costs and capital-
based costs. Total labor-based costs are calculated by multiplying the 
labor-based unit costs by the number of affected establishments and the 
number of heat-related emergencies per establishment (also shown in 
table VIII.C.6.). As discussed in section VIII.C.IV.F., labor-based 
unit costs incurred during heat-related emergencies consist of reducing 
an employee's body temperature before emergency medical services arrive 
as well as contacting emergency medical services and transporting 
employees to a place where they can be reached by an emergency medical 
provider. Total capital-based costs are calculated by multiplying the 
capital-based unit costs by the number of affected establishments. As 
discussed in section VIII.C.IV.F., capital-based unit costs consist of 
ice, ice sheets, and ice coolers. Cost frequency is assumed to be one-
time for purchases of ice sheets and ice coolers and the costs of 
purchasing ice when the initial heat trigger is met or exceeded are 
calculated on an annual basis. OSHA assumes that ice costs are incurred 
only when the initial heat trigger is met or exceeded. Using this 
assumption, OSHA multiplied the number of 8-hour work shift equivalents 
by the number of affected establishments and the unit cost for ice to 
determine the total annual costs associated with ice purchases.
    Table VIII.C.26. shows the annualized one-time, annual, and total 
annualized costs for each of these requirements by industry category 
and region, discounted (2 percent over a 10-year period) and 
undiscounted.

[[Page 70917]]



                 Table VIII.C.26--Total Costs--Heat Illness and Emergency Response and Planning
                                                     [2023$]
----------------------------------------------------------------------------------------------------------------
                                        One-time annualized                              Total annualized
        Industry category        --------------------------------     Annual     -------------------------------
                                        0%              2%                              0%              2%
----------------------------------------------------------------------------------------------------------------
                                         Medical Response--Non-Emergency
----------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and
 Fishing:
    Alaskan.....................              $0              $0             $22             $22             $22
    Central.....................               0               0           1,561           1,561           1,561
    Eastern.....................               0               0             822             822             822
    Pacific.....................               0               0              11              11              11
    Southern....................               0               0           1,427           1,427           1,427
    Western.....................               0               0             212             212             212
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0           4,055           4,055           4,055
Building Materials and Equipment
 Suppliers:
    Alaskan.....................               0               0               4               4               4
    Central.....................               0               0             390             390             390
    Eastern.....................               0               0             608             608             608
    Pacific.....................               0               0              10              10              10
    Southern....................               0               0             543             543             543
    Western.....................               0               0             342             342             342
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0           1,897           1,897           1,897
Commercial Kitchens:
    Alaskan.....................               0               0               8               8               8
    Central.....................               0               0             656             656             656
    Eastern.....................               0               0           1,098           1,098           1,098
    Pacific.....................               0               0              23              23              23
    Southern....................               0               0             791             791             791
    Western.....................               0               0             561             561             561
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0           3,136           3,136           3,136
Construction:
    Alaskan.....................               0               0              39              39              39
    Central.....................               0               0           3,014           3,014           3,014
    Eastern.....................               0               0           3,653           3,653           3,653
    Pacific.....................               0               0              54              54              54
    Southern....................               0               0           2,649           2,649           2,649
    Western.....................               0               0             726             726             726
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0          10,134          10,134          10,134
Drycleaning and Commercial
 Laundries:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0              38              38              38
    Eastern.....................               0               0              97              97              97
    Pacific.....................               0               0               1               1               1
    Southern....................               0               0              57              57              57
    Western.....................               0               0              35              35              35
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0             228             228             228
Landscaping and Facilities
 Support:
    Alaskan.....................               0               0              22              22              22
    Central.....................               0               0           1,829           1,829           1,829
    Eastern.....................               0               0           3,022           3,022           3,022
    Pacific.....................               0               0              40              40              40
    Southern....................               0               0           2,154           2,154           2,154
    Western.....................               0               0           1,699           1,699           1,699
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0           8,766           8,766           8,766
Maintenance and Repair:
    Alaskan.....................               0               0               3               3               3
    Central.....................               0               0             334             334             334
    Eastern.....................               0               0             442             442             442
    Pacific.....................               0               0               5               5               5
    Southern....................               0               0             359             359             359
    Western.....................               0               0             231             231             231
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0           1,376           1,376           1,376
Manufacturing:
    Alaskan.....................               0               0              13              13              13
    Central.....................               0               0           2,617           2,617           2,617
    Eastern.....................               0               0           2,545           2,545           2,545
    Pacific.....................               0               0              20              20              20
    Southern....................               0               0           1,908           1,908           1,908
    Western.....................               0               0           1,440           1,440           1,440
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0           8,544           8,544           8,544
Oil and Gas:
    Alaskan.....................               0               0              17              17              17
    Central.....................               0               0             671             671             671
    Eastern.....................               0               0             351             351             351
    Southern....................               0               0           2,546           2,546           2,546

[[Page 70918]]

 
    Western.....................               0               0             335             335             335
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0           3,921           3,921           3,921
Postal and Delivery Services:
    Alaskan.....................               0               0              19              19              19
    Central.....................               0               0             799             799             799
    Eastern.....................               0               0           1,011           1,011           1,011
    Pacific.....................               0               0              11              11              11
    Southern....................               0               0             744             744             744
    Western.....................               0               0             375             375             375
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0           2,958           2,958           2,958
Recreation and Amusement:
    Alaskan.....................               0               0               6               6               6
    Central.....................               0               0             267             267             267
    Eastern.....................               0               0             401             401             401
    Pacific.....................               0               0               5               5               5
    Southern....................               0               0             261             261             261
    Western.....................               0               0             175             175             175
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0           1,116           1,116           1,116
Sanitation and Waste Removal:
    Alaskan.....................               0               0               6               6               6
    Central.....................               0               0             217             217             217
    Eastern.....................               0               0             313             313             313
    Pacific.....................               0               0               5               5               5
    Southern....................               0               0             227             227             227
    Western.....................               0               0             119             119             119
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0             887             887             887
Telecommunications:
    Alaskan.....................               0               0              11              11              11
    Central.....................               0               0             696             696             696
    Eastern.....................               0               0             952             952             952
    Pacific.....................               0               0              10              10              10
    Southern....................               0               0             837             837             837
    Western.....................               0               0             467             467             467
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0           2,974           2,974           2,974
Temporary Help Services:
    Alaskan.....................               0               0               2               2               2
    Central.....................               0               0             432             432             432
    Eastern.....................               0               0             609             609             609
    Pacific.....................               0               0               6               6               6
    Southern....................               0               0             517             517             517
    Western.....................               0               0             306             306             306
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0           1,873           1,873           1,873
Transportation:
    Alaskan.....................               0               0              52              52              52
    Central.....................               0               0           3,215           3,215           3,215
    Eastern.....................               0               0           2,894           2,894           2,894
    Pacific.....................               0               0              36              36              36
    Southern....................               0               0           2,944           2,944           2,944
    Western.....................               0               0             726             726             726
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0           9,867           9,867           9,867
Utilities:
    Alaskan.....................               0               0              13              13              13
    Central.....................               0               0             546             546             546
    Eastern.....................               0               0             685             685             685
    Pacific.....................               0               0               5               5               5
    Southern....................               0               0             768             768             768
    Western.....................               0               0             315             315             315
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0           2,332           2,332           2,332
Warehousing:
    Alaskan.....................               0               0               2               2               2
    Central.....................               0               0             260             260             260
    Eastern.....................               0               0             329             329             329
    Pacific.....................               0               0               4               4               4
    Southern....................               0               0             323             323             323
    Western.....................               0               0             203             203             203
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0           1,120           1,120           1,120
Non-Core:
    Alaskan.....................               0               0             953             953             953
    Central.....................               0               0          57,371          57,371          57,371
    Eastern.....................               0               0          47,165          47,165          47,165

[[Page 70919]]

 
    Pacific.....................               0               0             435             435             435
    Southern....................               0               0          22,835          22,835          22,835
    Western.....................               0               0          19,411          19,411          19,411
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0         148,169         148,169         148,169
Total Costs for Medical
 Response--Non-Emergency:
    Alaskan.....................               0               0           1,193           1,193           1,193
    Central.....................               0               0          74,912          74,912          74,912
    Eastern.....................               0               0          66,997          66,997          66,997
    Pacific.....................               0               0             681             681             681
    Southern....................               0               0          41,890          41,890          41,890
    Western.....................               0               0          27,678          27,678          27,678
                                 -------------------------------------------------------------------------------
            Total...............               0               0         213,352         213,352         213,352
----------------------------------------------------------------------------------------------------------------
                                           Medical Response--Emergency
----------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and
 Fishing:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0              28              28              28
    Eastern.....................               0               0              15              15              15
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0              25              25              25
    Western.....................               0               0               4               4               4
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0              72              72              72
Building Materials and Equipment
 Suppliers:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0               6               6               6
    Eastern.....................               0               0              10              10              10
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0               9               9               9
    Western.....................               0               0               5               5               5
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0              30              30              30
Commercial Kitchens:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0              11              11              11
    Eastern.....................               0               0              18              18              18
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0              13              13              13
    Western.....................               0               0               9               9               9
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0              51              51              51
Construction:
    Alaskan.....................               0               0               1               1               1
    Central.....................               0               0              53              53              53
    Eastern.....................               0               0              64              64              64
    Pacific.....................               0               0               1               1               1
    Southern....................               0               0              47              47              47
    Western.....................               0               0              13              13              13
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0             178             178             178
Drycleaning and Commercial
 Laundries:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0               1               1               1
    Eastern.....................               0               0               2               2               2
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0               1               1               1
    Western.....................               0               0               1               1               1
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0               4               4               4
Landscaping and Facilities
 Support:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0              31              31              31
    Eastern.....................               0               0              51              51              51
    Pacific.....................               0               0               1               1               1
    Southern....................               0               0              36              36              36
    Western.....................               0               0              29              29              29
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0             147             147             147
Maintenance and Repair:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0               5               5               5
    Eastern.....................               0               0               7               7               7
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0               6               6               6
    Western.....................               0               0               4               4               4
                                 -------------------------------------------------------------------------------

[[Page 70920]]

 
        Subtotal................               0               0              22              22              22
Manufacturing:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0              43              43              43
    Eastern.....................               0               0              41              41              41
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0              31              31              31
    Western.....................               0               0              23              23              23
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0             139             139             139
Oil and Gas:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0              12              12              12
    Eastern.....................               0               0               6               6               6
    Southern....................               0               0              45              45              45
    Western.....................               0               0               6               6               6
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0              69              69              69
Postal and Delivery Services:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0              13              13              13
    Eastern.....................               0               0              16              16              16
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0              12              12              12
    Western.....................               0               0               6               6               6
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0              47              47              47
Recreation and Amusement:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0               4               4               4
    Eastern.....................               0               0               7               7               7
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0               4               4               4
    Western.....................               0               0               3               3               3
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0              18              18              18
Sanitation and Waste Removal:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0               4               4               4
    Eastern.....................               0               0               5               5               5
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0               4               4               4
    Western.....................               0               0               2               2               2
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0              15              15              15
Telecommunications:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0              11              11              11
    Eastern.....................               0               0              15              15              15
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0              13              13              13
    Western.....................               0               0               7               7               7
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0              48              48              48
Temporary Help Services:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0               7               7               7
    Eastern.....................               0               0              10              10              10
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0               9               9               9
    Western.....................               0               0               5               5               5
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0              32              32              32
Transportation:
    Alaskan.....................               0               0               1               1               1
    Central.....................               0               0              51              51              51
    Eastern.....................               0               0              46              46              46
    Pacific.....................               0               0               1               1               1
    Southern....................               0               0              47              47              47
    Western.....................               0               0              12              12              12
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0             158             158             158
Utilities:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0               9               9               9
    Eastern.....................               0               0              11              11              11
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0              12              12              12
    Western.....................               0               0               5               5               5
                                 -------------------------------------------------------------------------------

[[Page 70921]]

 
        Subtotal................               0               0              37              37              37
Warehousing:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0               4               4               4
    Eastern.....................               0               0               5               5               5
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0               5               5               5
    Western.....................               0               0               3               3               3
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0              18              18              18
Non-Core:
    Alaskan.....................               0               0              15              15              15
    Central.....................               0               0             914             914             914
    Eastern.....................               0               0             756             756             756
    Pacific.....................               0               0               7               7               7
    Southern....................               0               0             369             369             369
    Western.....................               0               0             313             313             313
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0           2,375           2,375           2,375
Total Costs for Medical
 Response--Emergency:
    Alaskan.....................               0               0              19              19              19
    Central.....................               0               0           1,207           1,207           1,207
    Eastern.....................               0               0           1,086           1,086           1,086
    Pacific.....................               0               0              11              11              11
    Southern....................               0               0             688             688             688
    Western.....................               0               0             449             449             449
                                 -------------------------------------------------------------------------------
            Total...............               0               0           3,460           3,460           3,460
----------------------------------------------------------------------------------------------------------------
                                       Contact Emergency Medical Services
----------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and
 Fishing:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0               4               4               4
    Eastern.....................               0               0               2               2               2
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0               4               4               4
    Western.....................               0               0               1               1               1
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0              12              12              12
Building Materials and Equipment
 Suppliers:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0               1               1               1
    Eastern.....................               0               0               2               2               2
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0               1               1               1
    Western.....................               0               0               1               1               1
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0               5               5               5
Commercial Kitchens:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0               2               2               2
    Eastern.....................               0               0               3               3               3
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0               2               2               2
    Western.....................               0               0               1               1               1
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0               8               8               8
Construction:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0               8               8               8
    Eastern.....................               0               0              10              10              10
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0               7               7               7
    Western.....................               0               0               2               2               2
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0              28              28              28
Drycleaning and Commercial
 Laundries:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0               0               0               0
    Eastern.....................               0               0               0               0               0
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0               0               0               0
    Western.....................               0               0               0               0               0
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0               1               1               1
Landscaping and Facilities
 Support:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0               5               5               5

[[Page 70922]]

 
    Eastern.....................               0               0               8               8               8
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0               6               6               6
    Western.....................               0               0               5               5               5
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0              24              24              24
Maintenance and Repair:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0               1               1               1
    Eastern.....................               0               0               1               1               1
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0               1               1               1
    Western.....................               0               0               1               1               1
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0               4               4               4
Manufacturing:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0               2               2               2
    Eastern.....................               0               0               1               1               1
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0               5               5               5
    Western.....................               0               0               4               4               4
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0              22              22              22
Oil and Gas:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0               2               2               2
    Eastern.....................               0               0               1               1               1
    Southern....................               0               0               7               7               7
    Western.....................               0               0               1               1               1
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0              11              11              11
Postal and Delivery Services:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0               2               2               2
    Eastern.....................               0               0               3               3               3
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0               2               2               2
    Western.....................               0               0               1               1               1
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0               8               8               8
Recreation and Amusement:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0               1               1               1
    Eastern.....................               0               0               1               1               1
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0               1               1               1
    Western.....................               0               0               0               0               0
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0               3               3               3
Sanitation and Waste Removal:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0               1               1               1
    Eastern.....................               0               0               1               1               1
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0               1               1               1
    Western.....................               0               0               0               0               0
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0               2               2               2
Telecommunications:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0               2               2               2
    Eastern.....................               0               0               2               2               2
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0               2               2               2
    Western.....................               0               0               1               1               1
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0               8               8               8
Temporary Help Services:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0               1               1               1
    Eastern.....................               0               0               2               2               2
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0               1               1               1
    Western.....................               0               0               1               1               1
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0               5               5               5
Transportation:
    Alaskan.....................               0               0               0               0               0

[[Page 70923]]

 
    Central.....................               0               0               8               8               8
    Eastern.....................               0               0               7               7               7
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0               8               8               8
    Western.....................               0               0               2               2               2
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0              25              25              25
Utilities:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0               1               1               1
    Eastern.....................               0               0               2               2               2
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0               2               2               2
    Western.....................               0               0               1               1               1
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0               6               6               6
Warehousing:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0               1               1               1
    Eastern.....................               0               0               1               1               1
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0               1               1               1
    Western.....................               0               0               1               1               1
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0               3               3               3
Non-Core:
    Alaskan.....................               0               0               2               2               2
    Central.....................               0               0             146             146             146
    Eastern.....................               0               0             121             121             121
    Pacific.....................               0               0               1               1               1
    Southern....................               0               0              59              59              59
    Western.....................               0               0              50              50              50
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0             380             380             380
Total Costs for Contact
 Emergency Medical Services:
    Alaskan.....................               0               0               3               3               3
    Central.....................               0               0             193             193             193
    Eastern.....................               0               0             174             174             174
    Pacific.....................               0               0               2               2               2
    Southern....................               0               0             110             110             110
    Western.....................               0               0              72              72              72
                                 -------------------------------------------------------------------------------
            Total...............               0               0             554             554             554
----------------------------------------------------------------------------------------------------------------
                                       Agriculture, Forestry, and Fishing
----------------------------------------------------------------------------------------------------------------
Transport Worker:
    Alaskan.....................               0               0               1               1               1
    Central.....................               0               0              67              67              67
    Eastern.....................               0               0              35              35              35
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0              61              61              61
    Western.....................               0               0               9               9               9
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0             173             173             173
Building Materials and Equipment
 Suppliers:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0              15              15              15
    Eastern.....................               0               0              23              23              23
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0              21              21              21
    Western.....................               0               0              13              13              13
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0              73              73              73
Commercial Kitchens:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0              26              26              26
    Eastern.....................               0               0              43              43              43
    Pacific.....................               0               0               1               1               1
    Southern....................               0               0              31              31              31
    Western.....................               0               0              22              22              22
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0             122             122             122
Construction:
    Alaskan.....................               0               0               2               2               2
    Central.....................               0               0             127             127             127
    Eastern.....................               0               0             154             154             154
    Pacific.....................               0               0               2               2               2
    Southern....................               0               0             112             112             112

[[Page 70924]]

 
    Western.....................               0               0              31              31              31
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0             427             427             427
Drycleaning and Commercial
 Laundries:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0               1               1               1
    Eastern.....................               0               0               4               4               4
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0               2               2               2
    Western.....................               0               0               1               1               1
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0               9               9               9
Landscaping and Facilities
 Support:
    Alaskan.....................               0               0               1               1               1
    Central.....................               0               0              74              74              74
    Eastern.....................               0               0             122             122             122
    Pacific.....................               0               0               2               2               2
    Southern....................               0               0              87              87              87
    Western.....................               0               0              69              69              69
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0             354             354             354
Maintenance and Repair:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0              13              13              13
    Eastern.....................               0               0              17              17              17
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0              14              14              14
    Western.....................               0               0               9               9               9
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0              53              53              53
Manufacturing:
    Alaskan.....................               0               0               1               1               1
    Central.....................               0               0             102             102             102
    Eastern.....................               0               0             100             100             100
    Pacific.....................               0               0               1               1               1
    Southern....................               0               0              75              75              75
    Western.....................               0               0              56              56              56
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0             334             334             334
Oil and Gas:
    Alaskan.....................               0               0               1               1               1
    Central.....................               0               0              28              28              28
    Eastern.....................               0               0              15              15              15
    Southern....................               0               0             108             108             108
    Western.....................               0               0              14              14              14
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0             166             166             166
Postal and Delivery Services:
    Alaskan.....................               0               0               1               1               1
    Central.....................               0               0              31              31              31
    Eastern.....................               0               0              39              39              39
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0              29              29              29
    Western.....................               0               0              14              14              14
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0             113             113             113
Recreation and Amusement:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0              10              10              10
    Eastern.....................               0               0              16              16              16
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0              10              10              10
    Western.....................               0               0               7               7               7
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0              43              43              43
Sanitation and Waste Removal:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0               9               9               9
    Eastern.....................               0               0              13              13              13
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0               9               9               9
    Western.....................               0               0               5               5               5
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0              36              36              36
Telecommunications:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0              27              27              27
    Eastern.....................               0               0              37              37              37
    Pacific.....................               0               0               0               0               0

[[Page 70925]]

 
    Southern....................               0               0              32              32              32
    Western.....................               0               0              18              18              18
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0             114             114             114
Temporary Help Services:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0              17              17              17
    Eastern.....................               0               0              25              25              25
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0              21              21              21
    Western.....................               0               0              12              12              12
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0              76              76              76
Transportation:
    Alaskan.....................               0               0               2               2               2
    Central.....................               0               0             123             123             123
    Eastern.....................               0               0             111             111             111
    Pacific.....................               0               0               1               1               1
    Southern....................               0               0             113             113             113
    Western.....................               0               0              28              28              28
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0             379             379             379
Utilities:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0              21              21              21
    Eastern.....................               0               0              26              26              26
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0              29              29              29
    Western.....................               0               0              12              12              12
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0              89              89              89
Warehousing:
    Alaskan.....................               0               0               0               0               0
    Central.....................               0               0              10              10              10
    Eastern.....................               0               0              13              13              13
    Pacific.....................               0               0               0               0               0
    Southern....................               0               0              12              12              12
    Western.....................               0               0               8               8               8
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0              43              43              43
Non-Core:
    Alaskan.....................               0               0              36              36              36
    Central.....................               0               0           2,194           2,194           2,194
    Eastern.....................               0               0           1,815           1,815           1,815
    Pacific.....................               0               0              17              17              17
    Southern....................               0               0             886             886             886
    Western.....................               0               0             751             751             751
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0           5,699           5,699           5,699
Total Costs for Transport
 Worker:
    Alaskan.....................               0               0              46              46              46
    Central.....................               0               0           2,896           2,896           2,896
    Eastern.....................               0               0           2,606           2,606           2,606
    Pacific.....................               0               0              27              27              27
    Southern....................               0               0           1,652           1,652           1,652
    Western.....................               0               0           1,079           1,079           1,079
                                 -------------------------------------------------------------------------------
            Total...............               0               0           8,305           8,305           8,305
    Ice Sheets..................
    Agriculture, Forestry, and
     Fishing....................
    Alaskan.....................           3,919           4,363               0           3,919           4,363
    Central.....................         284,403         316,616               0         284,403         316,616
    Eastern.....................         149,682         166,636               0         149,682         166,636
    Pacific.....................           2,022           2,251               0           2,022           2,251
    Southern....................         260,013         289,464               0         260,013         289,464
    Western.....................          38,559          42,926               0          38,559          42,926
                                 -------------------------------------------------------------------------------
        Subtotal................         738,598         822,255               0         738,598         822,255
Building Materials and Equipment
 Suppliers:
    Alaskan.....................             409             455               0             409             455
    Central.....................          32,691          36,393               0          32,691          36,393
    Eastern.....................          46,817          52,120               0          46,817          52,120
    Pacific.....................             741             825               0             741             825
    Southern....................          42,659          47,491               0          42,659          47,491
    Western.....................          25,237          28,096               0          25,237          28,096
                                 -------------------------------------------------------------------------------
        Subtotal................         148,554         165,380               0         148,554         165,380
Commercial Kitchens:
    Alaskan.....................           4,919           5,477               0           4,919           5,477

[[Page 70926]]

 
    Central.....................         392,047         436,452               0         392,047         436,452
    Eastern.....................         652,643         726,565               0         652,643         726,565
    Pacific.....................          12,463          13,875               0          12,463          13,875
    Southern....................         478,939         533,186               0         478,939         533,186
    Western.....................         333,020         370,740               0         333,020         370,740
                                 -------------------------------------------------------------------------------
        Subtotal................       1,874,032       2,086,295               0       1,874,032       2,086,295
Construction:
    Alaskan.....................           7,015           7,810               0           7,015           7,810
    Central.....................         538,801         599,828               0         538,801         599,828
    Eastern.....................         656,231         730,559               0         656,231         730,559
    Pacific.....................           9,774          10,881               0           9,774          10,881
    Southern....................         478,099         532,251               0         478,099         532,251
    Western.....................         136,369         151,815               0         136,369         151,815
                                 -------------------------------------------------------------------------------
        Subtotal................       1,826,289       2,033,145               0       1,826,289       2,033,145
Drycleaning and Commercial
 Laundries:
    Alaskan.....................             159             177               0             159             177
    Central.....................          19,859          22,109               0          19,859          22,109
    Eastern.....................          51,015          56,794               0          51,015          56,794
    Pacific.....................             402             447               0             402             447
    Southern....................          30,107          33,517               0          30,107          33,517
    Western.....................          18,521          20,619               0          18,521          20,619
                                 -------------------------------------------------------------------------------
        Subtotal................         120,063         133,662               0         120,063         133,662
Landscaping and Facilities
 Support:
    Alaskan.....................           1,015           1,130               0           1,015           1,130
    Central.....................         105,516         117,467               0         105,516         117,467
    Eastern.....................         171,723         191,173               0         171,723         191,173
    Pacific.....................           2,503           2,786               0           2,503           2,786
    Southern....................         120,865         134,555               0         120,865         134,555
    Western.....................          86,959          96,809               0          86,959          96,809
                                 -------------------------------------------------------------------------------
        Subtotal................         488,581         543,921               0         488,581         543,921
Maintenance and Repair:
    Alaskan.....................           1,733           1,929               0           1,733           1,929
    Central.....................         175,535         195,417               0         175,535         195,417
    Eastern.....................         232,663         259,016               0         232,663         259,016
    Pacific.....................           2,796           3,113               0           2,796           3,113
    Southern....................         188,980         210,385               0         188,980         210,385
    Western.....................         121,702         135,486               0         121,702         135,486
                                 -------------------------------------------------------------------------------
        Subtotal................         723,409         805,346               0         723,409         805,346
Manufacturing:
    Alaskan.....................             550             613               0             550             613
    Central.....................         108,365         120,639               0         108,365         120,639
    Eastern.....................         105,352         117,284               0         105,352         117,284
    Pacific.....................             841             936               0             841             936
    Southern....................          79,014          87,964               0          79,014          87,964
    Western.....................          59,634          66,388               0          59,634          66,388
                                 -------------------------------------------------------------------------------
        Subtotal................         353,755         393,824               0         353,755         393,824
Oil and Gas:
    Alaskan.....................             784             873               0             784             873
    Central.....................          31,780          35,379               0          31,780          35,379
    Eastern.....................          17,148          19,091               0          17,148          19,091
    Southern....................         115,134         128,175               0         115,134         128,175
    Western.....................          15,218          16,941               0          15,218          16,941
                                 -------------------------------------------------------------------------------
        Subtotal................         180,064         200,459               0         180,064         200,459
Postal and Delivery Services:
    Alaskan.....................           1,828           2,035               0           1,828           2,035
    Central.....................          78,479          87,368               0          78,479          87,368
    Eastern.....................          99,269         110,513               0          99,269         110,513
    Pacific.....................           1,048           1,167               0           1,048           1,167
    Southern....................          73,083          81,361               0          73,083          81,361
    Western.....................          36,803          40,972               0          36,803          40,972
                                 -------------------------------------------------------------------------------
        Subtotal................         290,510         323,415               0         290,510         323,415
Recreation and Amusement:
    Alaskan.....................           2,173           2,419               0           2,173           2,419
    Central.....................          86,303          96,078               0          86,303          96,078
    Eastern.....................         129,160         143,789               0         129,160         143,789
    Pacific.....................           1,602           1,783               0           1,602           1,783
    Southern....................          84,110          93,637               0          84,110          93,637
    Western.....................          56,791          63,223               0          56,791          63,223
                                 -------------------------------------------------------------------------------
        Subtotal................         360,139         400,930               0         360,139         400,930
Sanitation and Waste Removal:

[[Page 70927]]

 
    Alaskan.....................             177             197               0             177             197
    Central.....................           6,511           7,249               0           6,511           7,249
    Eastern.....................           9,397          10,461               0           9,397          10,461
    Pacific.....................             142             159               0             142             159
    Southern....................           6,819           7,591               0           6,819           7,591
    Western.....................           3,557           3,960               0           3,557           3,960
                                 -------------------------------------------------------------------------------
        Subtotal................          26,604          29,617               0          26,604          29,617
Telecommunications:
    Alaskan.....................             244             271               0             244             271
    Central.....................          14,806          16,483               0          14,806          16,483
    Eastern.....................          20,265          22,560               0          20,265          22,560
    Pacific.....................             221             246               0             221             246
    Southern....................          17,801          19,818               0          17,801          19,818
    Western.....................           9,937          11,063               0           9,937          11,063
                                 -------------------------------------------------------------------------------
        Subtotal................          63,274          70,441               0          63,274          70,441
Temporary Help Services:
    Alaskan.....................              69              76               0              69              76
    Central.....................          12,968          14,437               0          12,968          14,437
    Eastern.....................          18,273          20,343               0          18,273          20,343
    Pacific.....................             175             195               0             175             195
    Southern....................          15,516          17,274               0          15,516          17,274
    Western.....................           9,194          10,236               0           9,194          10,236
                                 -------------------------------------------------------------------------------
        Subtotal................          56,196          62,561               0          56,196          62,561
Transportation:
    Alaskan.....................           5,154           5,738               0           5,154           5,738
    Central.....................         315,763         351,528               0         315,763         351,528
    Eastern.....................         284,254         316,450               0         284,254         316,450
    Pacific.....................           3,541           3,942               0           3,541           3,942
    Southern....................         289,153         321,904               0         289,153         321,904
    Western.....................          71,295          79,371               0          71,295          79,371
                                 -------------------------------------------------------------------------------
        Subtotal................         969,160       1,078,933               0         969,160       1,078,933
Utilities:
    Alaskan.....................             783             872               0             783             872
    Central.....................          33,502          37,297               0          33,502          37,297
    Eastern.....................          41,998          46,755               0          41,998          46,755
    Pacific.....................             288             320               0             288             320
    Southern....................          47,105          52,440               0          47,105          52,440
    Western.....................          19,317          21,505               0          19,317          21,505
                                 -------------------------------------------------------------------------------
        Subtotal................         142,993         159,189               0         142,993         159,189
Warehousing:
    Alaskan.....................             175             194               0             175             194
    Central.....................          25,535          28,427               0          25,535          28,427
    Eastern.....................          32,288          35,945               0          32,288          35,945
    Pacific.....................             410             456               0             410             456
    Southern....................          31,697          35,287               0          31,697          35,287
    Western.....................          19,910          22,165               0          19,910          22,165
                                 -------------------------------------------------------------------------------
        Subtotal................         110,014         122,475               0         110,014         122,475
Non-Core:
    Alaskan.....................          31,903          35,517               0          31,903          35,517
    Central.....................       2,345,882       2,611,589               0       2,345,882       2,611,589
    Eastern.....................       3,852,103       4,288,412               0       3,852,103       4,288,412
    Pacific.....................          60,769          67,652               0          60,769          67,652
    Southern....................       3,037,027       3,381,017               0       3,037,027       3,381,017
    Western.....................       1,978,080       2,202,128               0       1,978,080       2,202,128
                                 -------------------------------------------------------------------------------
        Subtotal................      11,305,765      12,586,315               0      11,305,765      12,586,315
Total Costs for Ice Sheets:
    Alaskan.....................          63,010          70,146               0          63,010          70,146
    Central.....................       4,608,745       5,130,756               0       4,608,745       5,130,756
    Eastern.....................       6,570,282       7,314,467               0       6,570,282       7,314,467
    Pacific.....................          99,738         111,034               0          99,738         111,034
    Southern....................       5,396,123       6,007,317               0       5,396,123       6,007,317
    Western.....................       3,040,103       3,384,441               0       3,040,103       3,384,441
                                 -------------------------------------------------------------------------------
            Total...............      19,778,001      22,018,161               0      19,778,001      22,018,161
    Ice.........................
    Agriculture, Forestry, and
     Fishing....................
    Alaskan.....................               0               0             446             446             446
    Central.....................               0               0       5,904,480       5,904,480       5,904,480
    Eastern.....................               0               0       3,256,910       3,256,910       3,256,910
    Pacific.....................               0               0         145,592         145,592         145,592
    Southern....................               0               0      13,828,413      13,828,413      13,828,413
    Western.....................               0               0         984,176         984,176         984,176
                                 -------------------------------------------------------------------------------

[[Page 70928]]

 
        Subtotal................               0               0      24,120,016      24,120,016      24,120,016
Building Materials and Equipment
 Suppliers:
    Alaskan.....................               0               0              46              46              46
    Central.....................               0               0         647,575         647,575         647,575
    Eastern.....................               0               0         912,708         912,708         912,708
    Pacific.....................               0               0          53,375          53,375          53,375
    Southern....................               0               0       2,568,554       2,568,554       2,568,554
    Western.....................               0               0         670,491         670,491         670,491
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0       4,852,749       4,852,749       4,852,749
Commercial Kitchens:
    Alaskan.....................               0               0             559             559             559
    Central.....................               0               0       7,717,626       7,717,626       7,717,626
    Eastern.....................               0               0      12,712,137      12,712,137      12,712,137
    Pacific.....................               0               0         897,553         897,553         897,553
    Southern....................               0               0      28,462,002      28,462,002      28,462,002
    Western.....................               0               0       8,930,719       8,930,719       8,930,719
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0      58,720,595      58,720,595      58,720,595
Construction:
    Alaskan.....................               0               0             797             797             797
    Central.....................               0               0       9,565,873       9,565,873       9,565,873
    Eastern.....................               0               0      12,957,020      12,957,020      12,957,020
    Pacific.....................               0               0         703,866         703,866         703,866
    Southern....................               0               0      28,772,465      28,772,465      28,772,465
    Western.....................               0               0       4,062,547       4,062,547       4,062,547
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0      56,062,569      56,062,569      56,062,569
Drycleaning and Commercial
 Laundries:
    Alaskan.....................               0               0              18              18              18
    Central.....................               0               0         396,549         396,549         396,549
    Eastern.....................               0               0         954,226         954,226         954,226
    Pacific.....................               0               0          28,916          28,916          28,916
    Southern....................               0               0       1,772,663       1,772,663       1,772,663
    Western.....................               0               0         490,895         490,895         490,895
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0       3,643,268       3,643,268       3,643,268
Landscaping and Facilities
 Support:
    Alaskan.....................               0               0             115             115             115
    Central.....................               0               0       2,084,690       2,084,690       2,084,690
    Eastern.....................               0               0       3,394,782       3,394,782       3,394,782
    Pacific.....................               0               0         180,238         180,238         180,238
    Southern....................               0               0       7,349,405       7,349,405       7,349,405
    Western.....................               0               0       2,327,639       2,327,639       2,327,639
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0      15,336,869      15,336,869      15,336,869
Maintenance and Repair:
    Alaskan.....................               0               0             197             197             197
    Central.....................               0               0       3,446,620       3,446,620       3,446,620
    Eastern.....................               0               0       4,631,181       4,631,181       4,631,181
    Pacific.....................               0               0         201,369         201,369         201,369
    Southern....................               0               0      11,236,731      11,236,731      11,236,731
    Western.....................               0               0       3,270,460       3,270,460       3,270,460
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0      22,786,559      22,786,559      22,786,559
Manufacturing:
    Alaskan.....................               0               0              63              63              63
    Central.....................               0               0       1,878,565       1,878,565       1,878,565
    Eastern.....................               0               0       2,043,899       2,043,899       2,043,899
    Pacific.....................               0               0          60,540          60,540          60,540
    Southern....................               0               0       4,507,111       4,507,111       4,507,111
    Western.....................               0               0       1,570,311       1,570,311       1,570,311
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0      10,060,489      10,060,489      10,060,489
Oil and Gas:
    Alaskan.....................               0               0              89              89              89
    Central.....................               0               0         679,900         679,900         679,900
    Eastern.....................               0               0         310,644         310,644         310,644
    Southern....................               0               0       6,186,305       6,186,305       6,186,305
    Western.....................               0               0         322,752         322,752         322,752
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0       7,499,690       7,499,690       7,499,690
Postal and Delivery Services:
    Alaskan.....................               0               0             208             208             208
    Central.....................               0               0       1,592,194       1,592,194       1,592,194
    Eastern.....................               0               0       1,908,549       1,908,549       1,908,549
    Pacific.....................               0               0          75,491          75,491          75,491
    Southern....................               0               0       3,900,095       3,900,095       3,900,095
    Western.....................               0               0         957,348         957,348         957,348
                                 -------------------------------------------------------------------------------

[[Page 70929]]

 
        Subtotal................               0               0       8,433,885       8,433,885       8,433,885
Recreation and Amusement:
    Alaskan.....................               0               0             247             247             247
    Central.....................               0               0       1,656,570       1,656,570       1,656,570
    Eastern.....................               0               0       2,519,069       2,519,069       2,519,069
    Pacific.....................               0               0         115,370         115,370         115,370
    Southern....................               0               0       4,946,955       4,946,955       4,946,955
    Western.....................               0               0       1,503,157       1,503,157       1,503,157
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0      10,741,370      10,741,370      10,741,370
Sanitation and Waste Removal:
    Alaskan.....................               0               0              20              20              20
    Central.....................               0               0         125,786         125,786         125,786
    Eastern.....................               0               0         183,236         183,236         183,236
    Pacific.....................               0               0          10,260          10,260          10,260
    Southern....................               0               0         390,745         390,745         390,745
    Western.....................               0               0          96,609          96,609          96,609
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0         806,655         806,655         806,655
Telecommunications:
    Alaskan.....................               0               0              28              28              28
    Central.....................               0               0         296,733         296,733         296,733
    Eastern.....................               0               0         407,173         407,173         407,173
    Pacific.....................               0               0          15,899          15,899          15,899
    Southern....................               0               0         997,075         997,075         997,075
    Western.....................               0               0         267,246         267,246         267,246
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0       1,984,154       1,984,154       1,984,154
Temporary Help Services:
    Alaskan.....................               0               0               8               8               8
    Central.....................               0               0         249,978         249,978         249,978
    Eastern.....................               0               0         371,092         371,092         371,092
    Pacific.....................               0               0          12,610          12,610          12,610
    Southern....................               0               0         896,743         896,743         896,743
    Western.....................               0               0         253,049         253,049         253,049
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0       1,783,480       1,783,480       1,783,480
Transportation:
    Alaskan.....................               0               0             586             586             586
    Central.....................               0               0       6,347,834       6,347,834       6,347,834
    Eastern.....................               0               0       5,777,439       5,777,439       5,777,439
    Pacific.....................               0               0         255,024         255,024         255,024
    Southern....................               0               0      16,735,409      16,735,409      16,735,409
    Western.....................               0               0       2,032,671       2,032,671       2,032,671
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0      31,148,963      31,148,963      31,148,963
Utilities:
    Alaskan.....................               0               0              89              89              89
    Central.....................               0               0         676,799         676,799         676,799
    Eastern.....................               0               0         880,610         880,610         880,610
    Pacific.....................               0               0          20,720          20,720          20,720
    Southern....................               0               0       2,564,705       2,564,705       2,564,705
    Western.....................               0               0         498,202         498,202         498,202
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0       4,641,124       4,641,124       4,641,124
Warehousing:
    Alaskan.....................               0               0              20              20              20
    Central.....................               0               0         517,417         517,417         517,417
    Eastern.....................               0               0         684,456         684,456         684,456
    Pacific.....................               0               0          29,519          29,519          29,519
    Southern....................               0               0       1,745,873       1,745,873       1,745,873
    Western.....................               0               0         539,749         539,749         539,749
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0       3,517,034       3,517,034       3,517,034
Non-Core:
    Alaskan.....................               0               0           3,627           3,627           3,627
    Central.....................               0               0      47,433,999      47,433,999      47,433,999
    Eastern.....................               0               0      76,037,869      76,037,869      76,037,869
    Pacific.....................               0               0       4,376,294       4,376,294       4,376,294
    Southern....................               0               0     178,850,258     178,850,258     178,850,258
    Western.....................               0               0      52,965,329      52,965,329      52,965,329
                                 -------------------------------------------------------------------------------
        Subtotal................               0               0     359,667,375     359,667,375     359,667,375
Total Costs for Ice:
    Alaskan.....................               0               0           7,163           7,163           7,163
    Central.....................               0               0      91,219,187      91,219,187      91,219,187
    Eastern.....................               0               0     129,943,000     129,943,000     129,943,000
    Pacific.....................               0               0       7,182,636       7,182,636       7,182,636
    Southern....................               0               0     315,711,506     315,711,506     315,711,506

[[Page 70930]]

 
    Western.....................               0               0      81,743,351      81,743,351      81,743,351
                                 -------------------------------------------------------------------------------
            Total...............               0               0     625,806,844     625,806,844     625,806,844
    Ice Cooler..................
    Agriculture, Forestry, and
     Fishing....................
    Alaskan.....................           1,555           1,731               0           1,555           1,731
    Central.....................         112,807         125,585               0         112,807         125,585
    Eastern.....................          59,371          66,096               0          59,371          66,096
    Pacific.....................             802             893               0             802             893
    Southern....................         103,133         114,815               0         103,133         114,815
    Western.....................          15,294          17,027               0          15,294          17,027
                                 -------------------------------------------------------------------------------
        Subtotal................         292,962         326,145               0         292,962         326,145
Building Materials and Equipment
 Suppliers:
    Alaskan.....................             162             180               0             162             180
    Central.....................          12,967          14,435               0          12,967          14,435
    Eastern.....................          18,570          20,673               0          18,570          20,673
    Pacific.....................             294             327               0             294             327
    Southern....................          16,921          18,837               0          16,921          18,837
    Western.....................          10,010          11,144               0          10,010          11,144
                                 -------------------------------------------------------------------------------
        Subtotal................          58,923          65,597               0          58,923          65,597
Commercial Kitchens:
    Alaskan.....................           1,951           2,172               0           1,951           2,172
    Central.....................         155,504         173,117               0         155,504         173,117
    Eastern.....................         258,869         288,189               0         258,869         288,189
    Pacific.....................           4,944           5,503               0           4,944           5,503
    Southern....................         189,970         211,487               0         189,970         211,487
    Western.....................         132,091         147,053               0         132,091         147,053
                                 -------------------------------------------------------------------------------
        Subtotal................         743,329         827,522               0         743,329         827,522
Construction:
    Alaskan.....................           2,783           3,098               0           2,783           3,098
    Central.....................         213,714         237,920               0         213,714         237,920
    Eastern.....................         260,292         289,774               0         260,292         289,774
    Pacific.....................           3,877           4,316               0           3,877           4,316
    Southern....................         189,636         211,116               0         189,636         211,116
    Western.....................          54,090          60,217               0          54,090          60,217
                                 -------------------------------------------------------------------------------
        Subtotal................         724,392         806,440               0         724,392         806,440
Drycleaning and Commercial
 Laundries:
    Alaskan.....................              63              70               0              63              70
    Central.....................           7,877           8,769               0           7,877           8,769
    Eastern.....................          20,235          22,527               0          20,235          22,527
    Pacific.....................             159             177               0             159             177
    Southern....................          11,942          13,294               0          11,942          13,294
    Western.....................           7,346           8,178               0           7,346           8,178
                                 -------------------------------------------------------------------------------
        Subtotal................          47,623          53,017               0          47,623          53,017
Landscaping and Facilities
 Support:
    Alaskan.....................             403             448               0             403             448
    Central.....................          41,853          46,593               0          41,853          46,593
    Eastern.....................          68,113          75,828               0          68,113          75,828
    Pacific.....................             993           1,105               0             993           1,105
    Southern....................          47,941          53,371               0          47,941          53,371
    Western.....................          34,492          38,399               0          34,492          38,399
                                 -------------------------------------------------------------------------------
        Subtotal................         193,794         215,744               0         193,794         215,744
Maintenance and Repair:
    Alaskan.....................             687             765               0             687             765
    Central.....................          69,625          77,511               0          69,625          77,511
    Eastern.....................          92,285         102,738               0          92,285         102,738
    Pacific.....................           1,109           1,235               0           1,109           1,235
    Southern....................          74,958          83,449               0          74,958          83,449
    Western.....................          48,273          53,740               0          48,273          53,740
                                 -------------------------------------------------------------------------------
        Subtotal................         286,938         319,438               0         286,938         319,438
Manufacturing:
    Alaskan.....................             218             243               0             218             243
    Central.....................          42,983          47,851               0          42,983          47,851
    Eastern.....................          41,787          46,520               0          41,787          46,520
    Pacific.....................             333             371               0             333             371
    Southern....................          31,341          34,890               0          31,341          34,890
    Western.....................          23,653          26,333               0          23,653          26,333
                                 -------------------------------------------------------------------------------
        Subtotal................         140,316         156,209               0         140,316         156,209
Oil and Gas:
    Alaskan.....................             311             346               0             311             346
    Central.....................          12,605          14,033               0          12,605          14,033

[[Page 70931]]

 
    Eastern.....................           6,802           7,572               0           6,802           7,572
    Southern....................          45,668          50,840               0          45,668          50,840
    Western.....................           6,036           6,720               0           6,036           6,720
                                 -------------------------------------------------------------------------------
        Subtotal................          71,422          79,512               0          71,422          79,512
Postal and Delivery Services:
    Alaskan.....................             725             807               0             725             807
    Central.....................          31,128          34,654               0          31,128          34,654
    Eastern.....................          39,375          43,835               0          39,375          43,835
    Pacific.....................             416             463               0             416             463
    Southern....................          28,988          32,271               0          28,988          32,271
    Western.....................          14,598          16,251               0          14,598          16,251
                                 -------------------------------------------------------------------------------
        Subtotal................         115,230         128,281               0         115,230         128,281
Recreation and Amusement:
    Alaskan.....................             862             960               0             862             960
    Central.....................          34,232          38,109               0          34,232          38,109
    Eastern.....................          51,231          57,034               0          51,231          57,034
    Pacific.....................             635             707               0             635             707
    Southern....................          33,362          37,141               0          33,362          37,141
    Western.....................          22,526          25,077               0          22,526          25,077
                                 -------------------------------------------------------------------------------
        Subtotal................         142,848         159,027               0         142,848         159,027
Sanitation and Waste Removal:
    Alaskan.....................              70              78               0              70              78
    Central.....................           2,583           2,875               0           2,583           2,875
    Eastern.....................           3,727           4,149               0           3,727           4,149
    Pacific.....................              57              63               0              57              63
    Southern....................           2,705           3,011               0           2,705           3,011
    Western.....................           1,411           1,571               0           1,411           1,571
                                 -------------------------------------------------------------------------------
        Subtotal................          10,552          11,748               0          10,552          11,748
Telecommunications:
    Alaskan.....................              97             108               0              97             108
    Central.....................           5,873           6,538               0           5,873           6,538
    Eastern.....................           8,038           8,948               0           8,038           8,948
    Pacific.....................              88              97               0              88              97
    Southern....................           7,061           7,861               0           7,061           7,861
    Western.....................           3,942           4,388               0           3,942           4,388
                                 -------------------------------------------------------------------------------
        Subtotal................          25,097          27,940               0          25,097          27,940
Temporary Help Services:
    Alaskan.....................              27              30               0              27              30
    Central.....................           5,144           5,726               0           5,144           5,726
    Eastern.....................           7,248           8,069               0           7,248           8,069
    Pacific.....................              69              77               0              69              77
    Southern....................           6,155           6,852               0           6,155           6,852
    Western.....................           3,647           4,060               0           3,647           4,060
                                 -------------------------------------------------------------------------------
        Subtotal................          22,290          24,815               0          22,290          24,815
Transportation:
    Alaskan.....................           2,044           2,276               0           2,044           2,276
    Central.....................         125,246         139,432               0         125,246         139,432
    Eastern.....................         112,749         125,519               0         112,749         125,519
    Pacific.....................           1,405           1,564               0           1,405           1,564
    Southern....................         114,692         127,682               0         114,692         127,682
    Western.....................          28,279          31,482               0          28,279          31,482
                                 -------------------------------------------------------------------------------
        Subtotal................         384,414         427,955               0         384,414         427,955
Utilities:
    Alaskan.....................             311             346               0             311             346
    Central.....................          13,289          14,794               0          13,289          14,794
    Eastern.....................          16,658          18,545               0          16,658          18,545
    Pacific.....................             114             127               0             114             127
    Southern....................          18,684          20,800               0          18,684          20,800
    Western.....................           7,662           8,530               0           7,662           8,530
                                 -------------------------------------------------------------------------------
        Subtotal................          56,718          63,142               0          56,718          63,142
Warehousing:
    Alaskan.....................              69              77               0              69              77
    Central.....................          10,128          11,275               0          10,128          11,275
    Eastern.....................          12,807          14,257               0          12,807          14,257
    Pacific.....................             163             181               0             163             181
    Southern....................          12,572          13,996               0          12,572          13,996
    Western.....................           7,897           8,792               0           7,897           8,792
                                 -------------------------------------------------------------------------------
        Subtotal................          43,637          48,579               0          43,637          48,579
Non-Core:
    Alaskan.....................          12,654          14,088               0          12,654          14,088

[[Page 70932]]

 
    Central.....................         930,486       1,035,878               0         930,486       1,035,878
    Eastern.....................       1,527,924       1,700,984               0       1,527,924       1,700,984
    Pacific.....................          24,104          26,834               0          24,104          26,834
    Southern....................       1,204,627       1,341,069               0       1,204,627       1,341,069
    Western.....................         784,599         873,467               0         784,599         873,467
                                 -------------------------------------------------------------------------------
        Subtotal................       4,484,394       4,992,320               0       4,484,394       4,992,320
Total Costs for Ice Cooler:
    Alaskan.....................          24,993          27,823               0          24,993          27,823
    Central.....................       1,828,043       2,035,097               0       1,828,043       2,035,097
    Eastern.....................       2,606,080       2,901,259               0       2,606,080       2,901,259
    Pacific.....................          39,561          44,041               0          39,561          44,041
    Southern....................       2,140,354       2,382,782               0       2,140,354       2,382,782
    Western.....................       1,205,847       1,342,427               0       1,205,847       1,342,427
                                 -------------------------------------------------------------------------------
            Total...............       7,844,878       8,733,430               0       7,844,878       8,733,430
    Total Costs for Heat Illness
     and Emergency Response and
     Planning...................
    Agriculture, Forestry, and
     Fishing....................
    Alaskan.....................           5,474           6,094             468           5,942           6,562
    Central.....................         397,210         442,200       5,906,140       6,303,350       6,348,340
    Eastern.....................         209,053         232,732       3,257,783       3,466,836       3,490,515
    Pacific.....................           2,824           3,143         145,604         148,427         148,747
    Southern....................         363,147         404,279      13,829,931      14,193,078      14,234,210
    Western.....................          53,853          59,953         984,402       1,038,255       1,044,354
                                 -------------------------------------------------------------------------------
        Subtotal................       1,031,560       1,148,400      24,124,328      25,155,888      25,272,728
Building Materials and Equipment
 Suppliers:
    Alaskan.....................             571             635              51             622             686
    Central.....................          45,657          50,828         647,987         693,644         698,815
    Eastern.....................          65,387          72,793         913,350         978,737         986,143
    Pacific.....................           1,035           1,152          53,385          54,421          54,538
    Southern....................          59,579          66,328       2,569,128       2,628,707       2,635,456
    Western.....................          35,248          39,240         670,853         706,100         710,093
                                 -------------------------------------------------------------------------------
        Subtotal................         207,477         230,977       4,854,754       5,062,231       5,085,731
Commercial Kitchens:
    Alaskan.....................           6,871           7,649             568           7,438           8,216
    Central.....................         547,551         609,570       7,718,320       8,265,871       8,327,889
    Eastern.....................         911,512       1,014,754      12,713,298      13,624,809      13,728,052
    Pacific.....................          17,407          19,379         897,577         914,984         916,955
    Southern....................         668,909         744,673      28,462,838      29,131,747      29,207,511
    Western.....................         465,111         517,792       8,931,312       9,396,424       9,449,105
                                 -------------------------------------------------------------------------------
        Subtotal................       2,617,361       2,913,817      58,723,912      61,341,273      61,637,729
Construction:
    Alaskan.....................           9,798          10,908             839          10,637          11,746
    Central.....................         752,515         837,748       9,569,076      10,321,590      10,406,824
    Eastern.....................         916,523       1,020,333      12,960,902      13,877,425      13,981,235
    Pacific.....................          13,651          15,197         703,923         717,574         719,120
    Southern....................         667,736         743,367      28,775,279      29,443,015      29,518,646
    Western.....................         190,459         212,032       4,063,319       4,253,778       4,275,350
                                 -------------------------------------------------------------------------------
        Subtotal................       2,550,681       2,839,585      56,073,337      58,624,018      58,912,922
Drycleaning and Commercial
 Laundries:
    Alaskan.....................             222             247              18             241             266
    Central.....................          27,736          30,878         396,589         424,325         427,467
    Eastern.....................          71,250          79,320         954,328       1,025,579       1,033,649
    Pacific.....................             561             624          28,917          29,477          29,541
    Southern....................          42,049          46,812       1,772,724       1,814,773       1,819,536
    Western.....................          25,867          28,797         490,932         516,799         519,729
                                 -------------------------------------------------------------------------------
        Subtotal................         167,685         186,678       3,643,509       3,811,195       3,830,188
Landscaping and Facilities
 Support:
    Alaskan.....................           1,418           1,579             139           1,557           1,718
    Central.....................         147,368         164,060       2,086,628       2,233,996       2,250,688
    Eastern.....................         239,837         267,002       3,397,985       3,637,822       3,664,987
    Pacific.....................           3,495           3,891         180,281         183,777         184,172
    Southern....................         168,806         187,926       7,351,688       7,520,494       7,539,613
    Western.....................         121,451         135,207       2,329,439       2,450,890       2,464,646
                                 -------------------------------------------------------------------------------
        Subtotal................         682,376         759,665      15,346,160      16,028,535      16,105,825
Maintenance and Repair:
    Alaskan.....................           2,420           2,694             200           2,620           2,895
    Central.....................         245,160         272,928       3,446,973       3,692,133       3,719,902
    Eastern.....................         324,948         361,754       4,631,648       4,956,597       4,993,402
    Pacific.....................           3,905           4,348         201,375         205,280         205,722
    Southern....................         263,939         293,834      11,237,111      11,501,050      11,530,945
    Western.....................         169,974         189,226       3,270,705       3,440,679       3,459,931
                                 -------------------------------------------------------------------------------

[[Page 70933]]

 
        Subtotal................       1,010,347       1,124,784      22,788,013      23,798,360      23,912,797
Manufacturing:
    Alaskan.....................             768             856              77             845             932
    Central.....................         151,348         168,490       1,881,334       2,032,682       2,049,825
    Eastern.....................         147,139         163,805       2,046,592       2,193,731       2,210,396
    Pacific.....................           1,174           1,307          60,562          61,736          61,869
    Southern....................         110,355         122,854       4,509,130       4,619,485       4,631,984
    Western.....................          83,287          92,721       1,571,835       1,655,122       1,664,556
                                 -------------------------------------------------------------------------------
        Subtotal................         494,071         550,032      10,069,529      10,563,601      10,619,562
Oil and Gas:
    Alaskan.....................           1,095           1,219             108           1,202           1,326
    Central.....................          44,385          49,412         680,613         724,998         730,025
    Eastern.....................          23,950          26,663         311,017         334,968         337,681
    Southern....................         160,802         179,015       6,189,011       6,349,813       6,368,027
    Western.....................          21,254          23,661         323,109         344,363         346,770
                                 -------------------------------------------------------------------------------
        Subtotal................         251,486         279,971       7,503,858       7,755,344       7,783,829
Postal and Delivery Services:
    Alaskan.....................           2,553           2,842             227           2,780           3,069
    Central.....................         109,607         122,022       1,593,038       1,702,645       1,715,060
    Eastern.....................         138,644         154,348       1,909,617       2,048,261       2,063,965
    Pacific.....................           1,464           1,630          75,502          76,966          77,132
    Southern....................         102,071         113,632       3,900,882       4,002,953       4,014,514
    Western.....................          51,401          57,223         957,744       1,009,145       1,014,967
                                 -------------------------------------------------------------------------------
        Subtotal................         405,740         451,696       8,437,011       8,842,751       8,888,707
Recreation and Amusement:
    Alaskan.....................           3,035           3,379             254           3,289           3,632
    Central.....................         120,534         134,187       1,656,853       1,777,387       1,791,040
    Eastern.....................         180,391         200,823       2,519,494       2,699,885       2,720,317
    Pacific.....................           2,237           2,491         115,376         117,613         117,866
    Southern....................         117,472         130,778       4,947,232       5,064,704       5,078,010
    Western.....................          79,316          88,300       1,503,343       1,582,659       1,591,643
                                 -------------------------------------------------------------------------------
        Subtotal................         502,986         559,957      10,742,550      11,245,537      11,302,508
Sanitation and Waste Removal:
    Alaskan.....................             248             276              26             274             302
    Central.....................           9,094          10,124         126,016         135,110         136,140
    Eastern.....................          13,124          14,610         183,568         196,691         198,178
    Pacific.....................             199             222          10,265          10,464          10,487
    Southern....................           9,524          10,603         390,986         400,510         401,588
    Western.....................           4,968           5,531          96,734         101,703         102,266
                                 -------------------------------------------------------------------------------
        Subtotal................          37,157          41,365         807,595         844,752         848,960
Telecommunications:
    Alaskan.....................             340             379              40             380             419
    Central.....................          20,679          23,021         297,469         318,148         320,490
    Eastern.....................          28,303          31,508         408,180         436,483         439,688
    Pacific.....................             308             343          15,910          16,219          16,254
    Southern....................          24,862          27,678         997,959       1,022,821       1,025,637
    Western.....................          13,879          15,451         267,740         281,618         283,190
                                 -------------------------------------------------------------------------------
        Subtotal................          88,371          98,381       1,987,297       2,075,668       2,085,678
Temporary Help Services:
    Alaskan.....................              96             107              10             106             117
    Central.....................          18,112          20,163         250,436         268,548         270,600
    Eastern.....................          25,521          28,412         371,738         397,259         400,150
    Pacific.....................             245             272          12,616          12,861          12,888
    Southern....................          21,671          24,125         897,291         918,962         921,417
    Western.....................          12,841          14,296         253,374         266,215         267,669
                                 -------------------------------------------------------------------------------
        Subtotal................          78,486          87,376       1,785,465       1,863,951       1,872,841
Transportation:
    Alaskan.....................           7,198           8,014             641           7,840           8,655
    Central.....................         441,009         490,960       6,351,231       6,792,240       6,842,191
    Eastern.....................         397,003         441,969       5,780,498       6,177,501       6,222,468
    Pacific.....................           4,946           5,506         255,062         260,008         260,568
    Southern....................         403,844         449,586      16,738,520      17,142,365      17,188,106
    Western.....................          99,574         110,853       2,033,438       2,133,012       2,144,291
                                 -------------------------------------------------------------------------------
        Subtotal................       1,353,575       1,506,888      31,159,391      32,512,966      32,666,279
Utilities:
    Alaskan.....................           1,094           1,218             103           1,196           1,320
    Central.....................          46,791          52,091         677,376         724,167         729,467
    Eastern.....................          58,656          65,300         881,334         939,991         946,634
    Pacific.....................             402             447          20,725          21,126          21,172
    Southern....................          65,789          73,240       2,565,516       2,631,305       2,638,757
    Western.....................          26,979          30,034         498,535         525,513         528,569
                                 -------------------------------------------------------------------------------

[[Page 70934]]

 
        Subtotal................         199,711         222,331       4,643,589       4,843,299       4,865,920
Warehousing:
    Alaskan.....................             244             272              22             266             293
    Central.....................          35,663          39,702         517,691         553,354         557,394
    Eastern.....................          45,095          50,202         684,804         729,898         735,006
    Pacific.....................             572             637          29,523          30,096          30,161
    Southern....................          44,269          49,283       1,746,214       1,790,483       1,795,497
    Western.....................          27,808          30,957         539,964         567,771         570,921
                                 -------------------------------------------------------------------------------
        Subtotal................         153,651         171,054       3,518,218       3,671,869       3,689,272
Non-Core:
    Alaskan.....................          44,558          49,605           4,634          49,191          54,238
    Central.....................       3,276,369       3,647,467      47,494,625      50,770,993      51,142,092
    Eastern.....................       5,380,026       5,989,397      76,087,725      81,467,752      82,077,122
    Pacific.....................          84,873          94,486       4,376,753       4,461,626       4,471,239
    Southern....................       4,241,654       4,722,086     178,874,407     183,116,060     183,596,492
    Western.....................       2,762,679       3,075,595      52,985,853      55,748,532      56,061,448
                                 -------------------------------------------------------------------------------
        Subtotal................      15,790,158      17,578,635     359,823,997     375,614,155     377,402,632
            Total...............
    Alaskan.....................          88,002          97,970           8,424          96,426         106,394
    Central.....................       6,436,788       7,165,853      91,298,395      97,735,184      98,464,248
    Eastern.....................       9,176,362      10,215,726     130,013,862     139,190,225     140,229,588
    Pacific.....................         139,298         155,076       7,183,357       7,322,655       7,338,433
    Southern....................       7,536,477       8,390,099     315,755,847     323,292,325     324,145,946
    Western.....................       4,245,950       4,726,869      81,772,629      86,018,579      86,499,498
                                 -------------------------------------------------------------------------------
            Total...............      27,622,878      30,751,591     626,032,515     653,655,393     656,784,106
----------------------------------------------------------------------------------------------------------------
Source: OSHA estimate.
Note: Due to rounding, figures in the columns and rows may not sum to the totals shown.

G. Training
    All affected establishments would be required to provide training 
on heat-related hazards to at-risk workers and designated persons both 
upon promulgation and periodically thereafter.\79\ OSHA calculates the 
total costs of each training requirement by either multiplying the 
number of affected establishments by the corresponding unit costs or 
multiplying the number of affected employees by the corresponding unit 
costs. The unit costs to undergo employee trainings (initial, annual 
refresher, and supplemental) are employee-based and are combined with 
the number of affected employees. All other training-related unit costs 
are establishment-based (developing, preparing, conducting employee 
training (initial, annual refresher, supplemental) and supervisor 
training (initial, annual refresher)) and are combined with the number 
of affected establishments. OSHA assumes that one percent of affected 
establishments would incur the establishment-based cost of supplemental 
trainings annually. Additionally, OSHA assumes employers would incur 
the cost of providing supplemental training to one percent of employees 
annually.
---------------------------------------------------------------------------

    \79\ Employers would be required to conduct refresher trainings 
annually for both at-risk workers and designated persons. 
Supplemental trainings would also be required for at-risk workers 
when either (1) worker(s) heat exposure changes, (2) policies and 
procedures change, (3) worker(s) does not retain information, or (4) 
a heat-related injury or illness occurs that results in death, days 
away from work, medical treatment beyond first aid, or loss of 
consciousness.
---------------------------------------------------------------------------

    Table VIII.C.27. shows the annualized one-time, annual, and total 
annualized costs for each of these requirements by industry category, 
discounted (2 percent over a 10-year period) and undiscounted.

                                     Table VIII.C.27--Total Costs--Training
                                                     [2023]
----------------------------------------------------------------------------------------------------------------
                                        One-time annualized                              Total annualized
        Industry category        --------------------------------     Annual     -------------------------------
                                        0%              2%                              0%              2%
----------------------------------------------------------------------------------------------------------------
                                      Initial Employee Training Development
----------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and              $874,213        $973,231              $0        $874,213        $973,231
 Fishing........................
Building Materials and Equipment         196,858         219,155               0         196,858         219,155
 Suppliers......................
Commercial Kitchens.............       1,551,304       1,727,013               0       1,551,304       1,727,013
Construction....................       3,520,999       3,919,806               0       3,520,999       3,919,806
Drycleaning and Commercial               161,955         180,299               0         161,955         180,299
 Laundries......................
Landscaping and Facilities               661,920         736,893               0         661,920         736,893
 Support........................
Maintenance and Repair..........         965,373       1,074,716               0         965,373       1,074,716
Manufacturing...................         687,852         765,762               0         687,852         765,762
Oil and Gas.....................         356,567         396,953               0         356,567         396,953
Postal and Delivery Services....         429,895         478,587               0         429,895         478,587
Recreation and Amusement........         404,065         449,832               0         404,065         449,832
Sanitation and Waste Removal....          36,316          40,430               0          36,316          40,430
Telecommunications..............         138,034         153,668               0         138,034         153,668

[[Page 70935]]

 
Temporary Help Services.........          77,023          85,747               0          77,023          85,747
Transportation..................       1,433,544       1,595,915               0       1,433,544       1,595,915
Utilities.......................         234,921         261,529               0         234,921         261,529
Warehousing.....................         164,390         183,009               0         164,390         183,009
Non-Core........................      17,129,902      19,070,125               0      17,129,902      19,070,125
                                 -------------------------------------------------------------------------------
    Subtotal....................      29,025,131      32,312,671               0      29,025,131      32,312,671
----------------------------------------------------------------------------------------------------------------
                                  Initial Employee Training--Designated Person
----------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and               327,830         364,961               0         327,830         364,961
 Fishing........................
Building Materials and Equipment          73,822          82,183               0          73,822          82,183
 Suppliers......................
Commercial Kitchens.............         581,739         647,630               0         581,739         647,630
Construction....................       1,320,375       1,469,927               0       1,320,375       1,469,927
Drycleaning and Commercial                60,733          67,612               0          60,733          67,612
 Laundries......................
Landscaping and Facilities               248,220         276,335               0         248,220         276,335
 Support........................
Maintenance and Repair..........         362,015         403,019               0         362,015         403,019
Manufacturing...................         257,945         287,161               0         257,945         287,161
Oil and Gas.....................         133,712         148,857               0         133,712         148,857
Postal and Delivery Services....         161,211         179,470               0         161,211         179,470
Recreation and Amusement........         151,524         168,687               0         151,524         168,687
Sanitation and Waste Removal....          13,619          15,161               0          13,619          15,161
Telecommunications..............          51,763          57,626               0          51,763          57,626
Temporary Help Services.........          28,883          32,155               0          28,883          32,155
Transportation..................         537,579         598,468               0         537,579         598,468
Utilities.......................          88,095          98,074               0          88,095          98,074
Warehousing.....................          61,646          68,628               0          61,646          68,628
Non-Core........................       6,423,713       7,151,297               0       6,423,713       7,151,297
                                 -------------------------------------------------------------------------------
    Subtotal....................      10,884,424      12,117,251               0      10,884,424      12,117,251
----------------------------------------------------------------------------------------------------------------
                                    Initial Employee Training--At-Risk Worker
----------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and               934,279       1,040,101               0         934,279       1,040,101
 Fishing........................
Building Materials and Equipment         746,591         831,153               0         746,591         831,153
 Suppliers......................
Commercial Kitchens.............       4,066,902       4,527,541               0       4,066,902       4,527,541
Construction....................       4,331,381       4,821,976               0       4,331,381       4,821,976
Drycleaning and Commercial               122,360         136,219               0         122,360         136,219
 Laundries......................
Landscaping and Facilities             1,942,964       2,163,034               0       1,942,964       2,163,034
 Support........................
Maintenance and Repair..........       1,029,589       1,146,206               0       1,029,589       1,146,206
Manufacturing...................       2,507,091       2,791,058               0       2,507,091       2,791,058
Oil and Gas.....................         541,637         602,986               0         541,637         602,986
Postal and Delivery Services....         361,448         402,388               0         361,448         402,388
Recreation and Amusement........         724,272         806,307               0         724,272         806,307
Sanitation and Waste Removal....         142,218         158,326               0         142,218         158,326
Telecommunications..............         420,884         468,556               0         420,884         468,556
Temporary Help Services.........       2,505,173       2,788,922               0       2,505,173       2,788,922
Transportation..................       1,356,516       1,510,162               0       1,356,516       1,510,162
Utilities.......................         582,011         647,932               0         582,011         647,932
Warehousing.....................         553,790         616,515               0         553,790         616,515
Non-Core........................      53,834,831      59,932,448               0      53,834,831      59,932,448
                                 -------------------------------------------------------------------------------
    Subtotal....................      76,703,936      85,391,828               0      76,703,936      85,391,828
----------------------------------------------------------------------------------------------------------------
                                     Initial Supervisor Training Development
----------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and               437,106         486,615               0         437,106         486,615
 Fishing........................
Building Materials and Equipment          98,429         109,577               0          98,429         109,577
 Suppliers......................
Commercial Kitchens.............         775,652         863,507               0         775,652         863,507
Construction....................       1,760,499       1,959,903               0       1,760,499       1,959,903
Drycleaning and Commercial                80,978          90,150               0          80,978          90,150
 Laundries......................
Landscaping and Facilities               330,960         368,446               0         330,960         368,446
 Support........................
Maintenance and Repair..........         482,687         537,358               0         482,687         537,358
Manufacturing...................         343,926         382,881               0         343,926         382,881
Oil and Gas.....................         178,283         198,477               0         178,283         198,477
Postal and Delivery Services....         214,948         239,294               0         214,948         239,294
Recreation and Amusement........         202,033         224,916               0         202,033         224,916
Sanitation and Waste Removal....          18,158          20,215               0          18,158          20,215
Telecommunications..............          69,017          76,834               0          69,017          76,834
Temporary Help Services.........          38,511          42,873               0          38,511          42,873
Transportation..................         716,772         797,958               0         716,772         797,958
Utilities.......................         117,460         130,765               0         117,460         130,765
Warehousing.....................          82,195          91,505               0          82,195          91,505
Non-Core........................       8,564,951       9,535,063               0       8,564,951       9,535,063
                                 -------------------------------------------------------------------------------
    Subtotal....................      14,512,566      16,156,335               0      14,512,566      16,156,335
----------------------------------------------------------------------------------------------------------------
                                     Initial Supervisor Training--Supervisor
----------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and               273,191         304,135               0         273,191         304,135
 Fishing........................

[[Page 70936]]

 
Building Materials and Equipment          61,518          68,486               0          61,518          68,486
 Suppliers......................
Commercial Kitchens.............         484,783         539,692               0         484,783         539,692
Construction....................       1,100,312       1,224,939               0       1,100,312       1,224,939
Drycleaning and Commercial                50,611          56,344               0          50,611          56,344
 Laundries......................
Landscaping and Facilities               206,850         230,279               0         206,850         230,279
 Support........................
Maintenance and Repair..........         301,679         335,849               0         301,679         335,849
Manufacturing...................         214,954         239,301               0         214,954         239,301
Oil and Gas.....................         111,427         124,048               0         111,427         124,048
Postal and Delivery Services....         134,342         149,559               0         134,342         149,559
Recreation and Amusement........         126,270         140,572               0         126,270         140,572
Sanitation and Waste Removal....          11,349          12,634               0          11,349          12,634
Telecommunications..............          43,136          48,021               0          43,136          48,021
Temporary Help Services.........          24,070          26,796               0          24,070          26,796
Transportation..................         447,983         498,723               0         447,983         498,723
Utilities.......................          73,413          81,728               0          73,413          81,728
Warehousing.....................          51,372          57,190               0          51,372          57,190
Non-Core........................       5,353,094       5,959,414               0       5,353,094       5,959,414
                                 -------------------------------------------------------------------------------
    Subtotal....................       9,070,353      10,097,710               0       9,070,353      10,097,710
----------------------------------------------------------------------------------------------------------------
                                 Initial Supervisor Training--Designated Person
----------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and               218,553         243,308               0         218,553         243,308
 Fishing........................
Building Materials and Equipment          49,214          54,789               0          49,214          54,789
 Suppliers......................
Commercial Kitchens.............         387,826         431,753               0         387,826         431,753
Construction....................         880,250         979,951               0         880,250         979,951
Drycleaning and Commercial                40,489          45,075               0          40,489          45,075
 Laundries......................
Landscaping and Facilities               165,480         184,223               0         165,480         184,223
 Support........................
Maintenance and Repair..........         241,343         268,679               0         241,343         268,679
Manufacturing...................         171,963         191,440               0         171,963         191,440
Oil and Gas.....................          89,142          99,238               0          89,142          99,238
Postal and Delivery Services....         107,474         119,647               0         107,474         119,647
Recreation and Amusement........         101,016         112,458               0         101,016         112,458
Sanitation and Waste Removal....           9,079          10,107               0           9,079          10,107
Telecommunications..............          34,508          38,417               0          34,508          38,417
Temporary Help Services.........          19,256          21,437               0          19,256          21,437
Transportation..................         358,386         398,979               0         358,386         398,979
Utilities.......................          58,730          65,382               0          58,730          65,382
Warehousing.....................          41,097          45,752               0          41,097          45,752
Non-Core........................       4,282,475       4,767,531               0       4,282,475       4,767,531
                                 -------------------------------------------------------------------------------
    Subtotal....................       7,256,283       8,078,168               0       7,256,283       8,078,168
----------------------------------------------------------------------------------------------------------------
                              Annual Employee Refresher Training--Designated Person
----------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and                     0               0       1,768,652       1,768,652       1,768,652
 Fishing........................
Building Materials and Equipment               0               0         369,108         369,108         369,108
 Suppliers......................
Commercial Kitchens.............               0               0       2,850,713       2,850,713       2,850,713
Construction....................               0               0         527,929         527,929         527,929
Drycleaning and Commercial                     0               0         303,666         303,666         303,666
 Laundries......................
Landscaping and Facilities                     0               0       1,209,995       1,209,995       1,209,995
 Support........................
Maintenance and Repair..........               0               0       1,810,074       1,810,074       1,810,074
Oil and Gas.....................               0               0         672,075         672,075         672,075
Postal and Delivery Services....               0               0         806,053         806,053         806,053
Recreation and Amusement........               0               0         757,622         757,622         757,622
Sanitation and Waste Removal....               0               0          68,093          68,093          68,093
Telecommunications..............               0               0         258,814         258,814         258,814
Temporary Help Services.........               0               0         144,417         144,417         144,417
Transportation..................               0               0       2,950,027       2,950,027       2,950,027
Utilities.......................               0               0         618,234         618,234         618,234
Warehousing.....................               0               0         308,231         308,231         308,231
Non-Core........................               0               0      32,061,160      32,061,160      32,061,160
                                 -------------------------------------------------------------------------------
    Subtotal....................               0               0      47,484,865      47,484,865      47,484,865
----------------------------------------------------------------------------------------------------------------
                               Annual Employee Refresher Training--At-Risk Worker
----------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and                     0               0       6,150,895       6,150,895       6,150,895
 Fishing........................
Building Materials and Equipment               0               0       3,732,953       3,732,953       3,732,953
 Suppliers......................
Commercial Kitchens.............               0               0      19,973,908      19,973,908      19,973,908
Construction....................               0               0       7,431,366       7,431,366       7,431,366
Drycleaning and Commercial                     0               0         611,800         611,800         611,800
 Laundries......................
Landscaping and Facilities                     0               0       9,244,018       9,244,018       9,244,018
 Support........................
Maintenance and Repair..........               0               0       5,147,944       5,147,944       5,147,944
Oil and Gas.....................               0               0       2,725,803       2,725,803       2,725,803
Postal and Delivery Services....               0               0       1,807,242       1,807,242       1,807,242
Recreation and Amusement........               0               0       3,621,359       3,621,359       3,621,359
Sanitation and Waste Removal....               0               0         711,089         711,089         711,089
Telecommunications..............               0               0       2,104,420       2,104,420       2,104,420

[[Page 70937]]

 
Temporary Help Services.........               0               0      12,525,865      12,525,865      12,525,865
Transportation..................               0               0       7,140,067       7,140,067       7,140,067
Utilities.......................               0               0       4,739,454       4,739,454       4,739,454
Warehousing.....................               0               0       2,768,949       2,768,949       2,768,949
Non-Core........................               0               0     268,614,044     268,614,044     268,614,044
                                 -------------------------------------------------------------------------------
    Subtotal....................               0               0     359,051,175     359,051,175     359,051,175
----------------------------------------------------------------------------------------------------------------
                                Annual Supervisor Refresher Training--Supervisor
----------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and                     0               0       1,473,877       1,473,877       1,473,877
 Fishing........................
Building Materials and Equipment               0               0         307,590         307,590         307,590
 Suppliers......................
Commercial Kitchens.............               0               0       2,375,594       2,375,594       2,375,594
Construction....................               0               0         439,941         439,941         439,941
Drycleaning and Commercial                     0               0         253,055         253,055         253,055
 Laundries......................
Landscaping and Facilities                     0               0       1,008,329       1,008,329       1,008,329
 Support........................
Maintenance and Repair..........               0               0       1,508,395       1,508,395       1,508,395
Oil and Gas.....................               0               0         560,062         560,062         560,062
Postal and Delivery Services....               0               0         671,711         671,711         671,711
Recreation and Amusement........               0               0         631,352         631,352         631,352
Sanitation and Waste Removal....               0               0          56,744          56,744          56,744
Telecommunications..............               0               0         215,678         215,678         215,678
Temporary Help Services.........               0               0         120,348         120,348         120,348
Transportation..................               0               0       2,458,356       2,458,356       2,458,356
Utilities.......................               0               0         515,195         515,195         515,195
Warehousing.....................               0               0         256,859         256,859         256,859
Non-Core........................               0               0      26,717,633      26,717,633      26,717,633
                                 -------------------------------------------------------------------------------
    Subtotal....................               0               0      39,570,721      39,570,721      39,570,721
----------------------------------------------------------------------------------------------------------------
                             Annual Supervisor Refresher Training--Designated Person
----------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and                     0               0       1,179,102       1,179,102       1,179,102
 Fishing........................
Building Materials and Equipment               0               0         246,072         246,072         246,072
 Suppliers......................
Commercial Kitchens.............               0               0       1,900,475       1,900,475       1,900,475
Construction....................               0               0         351,953         351,953         351,953
Drycleaning and Commercial                     0               0         202,444         202,444         202,444
 Laundries......................
Landscaping and Facilities                     0               0         806,663         806,663         806,663
 Support........................
Maintenance and Repair..........               0               0       1,206,716       1,206,716       1,206,716
Oil and Gas.....................               0               0         448,050         448,050         448,050
Postal and Delivery Services....               0               0         537,369         537,369         537,369
Recreation and Amusement........               0               0         505,082         505,082         505,082
Sanitation and Waste Removal....               0               0          45,395          45,395          45,395
Telecommunications..............               0               0         172,542         172,542         172,542
Temporary Help Services.........               0               0          96,278          96,278          96,278
Transportation..................               0               0       1,966,685       1,966,685       1,966,685
Utilities.......................               0               0         412,156         412,156         412,156
Warehousing.....................               0               0         205,487         205,487         205,487
Non-Core........................               0               0      21,374,107      21,374,107      21,374,107
                                 -------------------------------------------------------------------------------
    Subtotal....................               0               0      31,656,577      31,656,577      31,656,577
----------------------------------------------------------------------------------------------------------------
                           Supplemental Employee Refresher Training--Designated Person
----------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and                     0               0          17,687          17,687          17,687
 Fishing........................
Building Materials and Equipment               0               0           3,691           3,691           3,691
 Suppliers......................
Commercial Kitchens.............               0               0          28,507          28,507          28,507
Construction....................               0               0           5,279           5,279           5,279
Drycleaning and Commercial                     0               0           3,037           3,037           3,037
 Laundries......................
Landscaping and Facilities                     0               0          12,100          12,100          12,100
 Support........................
Maintenance and Repair..........               0               0          18,101          18,101          18,101
Oil and Gas.....................               0               0           6,721           6,721           6,721
Postal and Delivery Services....               0               0           8,061           8,061           8,061
Recreation and Amusement........               0               0           7,576           7,576           7,576
Sanitation and Waste Removal....               0               0             681             681             681
Telecommunications..............               0               0           2,588           2,588           2,588
Temporary Help Services.........               0               0           1,444           1,444           1,444
Transportation..................               0               0          29,500          29,500          29,500
Utilities.......................               0               0           6,182           6,182           6,182
Warehousing.....................               0               0           3,082           3,082           3,082
Non-Core........................               0               0         320,612         320,612         320,612
                                 -------------------------------------------------------------------------------
    Subtotal....................               0               0         474,849         474,849         474,849
----------------------------------------------------------------------------------------------------------------
                            Supplemental Employee Refresher Training--At-Risk Worker
----------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and                     0               0          61,509          61,509          61,509
 Fishing........................
Building Materials and Equipment               0               0          37,330          37,330          37,330
 Suppliers......................
Commercial Kitchens.............               0               0         199,739         199,739         199,739

[[Page 70938]]

 
Construction....................               0               0          74,314          74,314          74,314
Drycleaning and Commercial                     0               0           6,118           6,118           6,118
 Laundries......................
Landscaping and Facilities                     0               0          92,440          92,440          92,440
 Support........................
Maintenance and Repair..........               0               0          51,479          51,479          51,479
Oil and Gas.....................               0               0          27,258          27,258          27,258
Postal and Delivery Services....               0               0          18,072          18,072          18,072
Recreation and Amusement........               0               0          36,214          36,214          36,214
Sanitation and Waste Removal....               0               0           7,111           7,111           7,111
Telecommunications..............               0               0          21,044          21,044          21,044
Temporary Help Services.........               0               0         125,259         125,259         125,259
Transportation..................               0               0          71,401          71,401          71,401
Utilities.......................               0               0          47,395          47,395          47,395
Warehousing.....................               0               0          27,689          27,689          27,689
Non-Core........................               0               0       2,686,140       2,686,140       2,686,140
                                 -------------------------------------------------------------------------------
    Subtotal....................               0               0       3,590,512       3,590,512       3,590,512
----------------------------------------------------------------------------------------------------------------
                                                      Total
----------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and             3,065,172       3,412,350      10,651,721      13,716,894      14,064,071
 Fishing........................
Building Materials and Equipment       1,226,431       1,365,343       4,696,744       5,923,175       6,062,087
 Suppliers......................
Commercial Kitchens.............       7,848,207       8,737,136      27,328,936      35,177,143      36,066,072
Construction....................      12,913,815      14,376,502       8,830,781      21,744,597      23,207,283
Drycleaning and Commercial               517,126         575,699       1,380,121       1,897,247       1,955,819
 Laundries......................
Landscaping and Facilities             3,556,395       3,959,211      12,373,546      15,929,940      16,332,756
 Support........................
Maintenance and Repair..........       3,382,686       3,765,827       9,742,711      13,125,396      13,508,537
Manufacturing...................       4,183,731       4,657,602               0       4,183,731       4,657,602
Oil and Gas.....................       1,410,768       1,570,559       4,439,969       5,850,737       6,010,528
Postal and Delivery Services....       1,409,318       1,568,945       3,848,509       5,257,827       5,417,453
Recreation and Amusement........       1,709,181       1,902,772       5,559,205       7,268,385       7,461,976
Sanitation and Waste Removal....         230,739         256,874         889,114       1,119,853       1,145,988
Telecommunications..............         757,342         843,122       2,775,086       3,532,428       3,618,208
Temporary Help Services.........       2,692,916       2,997,929      13,013,611      15,706,527      16,011,540
Transportation..................       4,850,780       5,400,205      14,616,036      19,466,817      20,016,242
Utilities.......................       1,154,630       1,285,410       6,338,616       7,493,247       7,624,026
Warehousing.....................         954,490       1,062,600       3,570,298       4,524,787       4,632,898
Non-Core........................      95,588,967     106,415,877     351,773,696     447,362,662     458,189,573
                                 -------------------------------------------------------------------------------
    Total.......................     147,452,693     164,153,963     481,828,698     629,281,391     645,982,661
----------------------------------------------------------------------------------------------------------------
Source: OSHA.
Note: Due to rounding, figures in the columns and rows may not sum to the totals shown.

H. Recordkeeping
    The proposed standard would require affected indoor establishments 
to maintain environmental measurements for six months. Certain models 
of environmental monitoring equipment can automatically upload 
measurements taken to a recordkeeping database. OSHA assumes that 
establishments required to maintain these records would purchase a 
wireless temperature and humidity data logger with this capability 
(cost captured under the Identifying Heat Hazards provision in section 
VIII.C.V.C.). For this reason, OSHA assumes that establishments would 
not incur an additional cost to maintain these records beyond the time 
required to take the measurements themselves (also captured in section 
VIII.C.V.C.).
I. Total Costs of the Proposed Standard
    Accounting for the costs associated with all provisions, OSHA 
estimates that annualized costs, using a 2 percent discount rate over a 
ten-year period, would equal 7.8 billion. Table VIII.C.28. shows the 
total costs of the proposed standard by industry category and region. 
Table VIII.C.29. shows the total costs of the proposed standard by 
provision.

                                    Table VIII.C.28--Total Costs of Proposed Standard by Industry Category and Region
                                                                         [2023]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                       Periodic costs annualized                                              Total annualized \a\
                                       One-time    --------------------------------      Annual         Cost savings   ---------------------------------
                                                          0%              2%                                                   0%               2%
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                           Agriculture, Forestry, and Fishing
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan..........................         $382,520         $25,400         $23,728           $91,573                $7         $132,358         $136,792
Central..........................       32,095,286       1,874,386       1,751,017        62,352,975        28,665,280       37,084,663       37,455,687
Eastern..........................       17,835,946         955,385         892,504        47,389,145        24,123,746       25,144,533       25,350,373
Pacific..........................          234,288          13,394          12,512           934,183           384,690          574,262          576,969
Southern.........................       30,484,939       1,686,951       1,575,919       225,927,630       129,505,465       99,639,354       99,991,389
Western..........................       10,348,543         953,696         890,925        41,033,629        18,153,681       24,010,171       24,131,198
                                  ----------------------------------------------------------------------------------------------------------------------
    Subtotal.....................       91,381,522       5,509,211       5,146,605       377,729,135       200,832,869      186,585,339      187,642,407
--------------------------------------------------------------------------------------------------------------------------------------------------------

[[Page 70939]]

 
                                                       Building Materials and Equipment Suppliers
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan..........................           73,244           6,454           6,029            22,293                11           30,252           31,108
Central..........................        6,164,179         536,834         501,500        20,645,717        10,913,203       10,402,615       10,474,581
Eastern..........................        8,768,769         785,209         733,528        34,605,315        19,559,927       16,000,785       16,103,245
Pacific..........................          137,453          12,450          11,631         1,020,163           507,369          527,784          529,391
Southern.........................        8,097,617         709,966         663,237       126,957,154        81,071,558       46,766,355       46,860,912
Western..........................        5,225,565         522,755         488,349        15,565,091         7,398,609        8,741,314        8,802,592
                                  ----------------------------------------------------------------------------------------------------------------------
    Subtotal.....................       28,466,828       2,573,667       2,404,273       198,815,733       119,450,676       82,469,106       82,801,829
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                   Commercial Kitchens
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan..........................          549,495          76,847          71,789           165,987                19          228,602          235,133
Central..........................       49,420,733       6,134,657       5,730,885       102,302,796        50,480,882       57,377,453       57,961,753
Eastern..........................       81,115,976      10,278,954       9,602,411       205,636,428       111,478,395      103,297,526      104,257,396
Pacific..........................        1,643,878         197,251         184,268         8,155,868         3,774,306        4,565,675        4,585,083
Southern.........................       64,789,002       7,549,866       7,052,947       658,904,303       422,956,059      243,182,131      243,946,159
Western..........................       45,955,018       6,478,114       6,051,736        95,928,702        43,836,108       57,335,907       57,882,325
                                  ----------------------------------------------------------------------------------------------------------------------
    Subtotal.....................      243,474,102      30,715,689      28,694,036     1,071,094,084       632,525,768      465,987,295      468,867,850
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                      Construction
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan..........................        1,970,414          90,248          84,308           381,506               146          587,427          610,106
Central..........................      124,809,723       5,773,126       5,393,149       276,994,643       143,672,185      146,380,743      147,817,492
Eastern..........................      185,264,838       8,472,733       7,915,072       563,370,759       318,816,805      263,927,711      266,060,003
Pacific..........................        2,828,279         128,458         120,003        20,460,443        10,357,236       10,398,881       10,431,429
Southern.........................      140,183,098       6,281,225       5,867,806     1,990,987,667     1,252,043,769      753,590,330      755,203,238
Western..........................       95,685,192       5,693,786       5,319,031       252,822,597       131,327,431      131,633,064      132,739,616
                                  ----------------------------------------------------------------------------------------------------------------------
    Subtotal.....................      550,741,543      26,439,574      24,699,368     3,105,017,615     1,856,217,570    1,306,518,156    1,312,861,883
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                          Drycleaning and Commercial Laundries
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan..........................           20,363           3,291           3,075             6,992                 1            9,356            9,600
Central..........................        2,472,950         410,674         383,645         3,748,206         1,537,412        2,499,157        2,528,809
Eastern..........................        6,132,138       1,054,962         985,526         9,594,795         4,179,153        6,134,352        6,208,027
Pacific..........................           60,013           8,303           7,757           324,887           154,506          177,212          177,925
Southern.........................        3,813,305         622,595         581,616        23,397,552        13,735,831       10,105,311       10,150,992
Western..........................        2,485,111         447,179         417,746         3,716,313         1,369,087        2,640,455        2,670,391
                                  ----------------------------------------------------------------------------------------------------------------------
    Subtotal.....................       14,983,879       2,547,005       2,379,365        40,788,745        20,975,991       21,565,843       21,745,744
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                           Landscaping and Facilities Support
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan..........................          197,905           9,247           8,639            57,613                43           78,285           80,564
Central..........................       15,928,220         910,565         850,633        52,336,359        26,156,301       27,863,936       28,047,989
Eastern..........................       26,916,385       1,487,495       1,389,590       122,773,476        67,859,770       57,754,094       58,064,912
Pacific..........................          437,568          23,090          21,570         4,330,295         2,117,991        2,258,370        2,263,419
Southern.........................       20,065,797       1,057,656         988,043       363,466,916       223,153,028      142,426,233      142,657,739
Western..........................       15,235,305         858,763         802,240        48,189,915        22,716,571       27,082,750       27,258,747
                                  ----------------------------------------------------------------------------------------------------------------------
    Subtotal.....................       78,781,181       4,346,816       4,060,716       591,154,573       342,003,705      257,463,668      258,373,369
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                 Maintenance and Repair
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan..........................          215,858          26,776          25,014            67,597                14           91,847           94,399
Central..........................       21,311,213       2,695,519       2,518,105        37,119,880        16,211,936       23,308,617       23,560,779
Eastern..........................       29,094,622       3,559,615       3,325,327        64,302,224        31,787,358       35,780,290       36,124,066
Pacific..........................          351,104          42,847          40,027         1,479,871           638,831          880,434          884,582
Southern.........................       24,302,282       2,900,712       2,709,792       199,152,349       119,019,773       82,852,875       83,139,736
Western..........................       16,832,123       2,263,433       2,114,457        30,066,027        12,222,844       19,752,738       19,952,439
                                  ----------------------------------------------------------------------------------------------------------------------
    Subtotal.....................       92,107,202      11,488,901      10,732,722       332,187,947       179,880,757      162,666,801      163,756,002
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                      Manufacturing
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan..........................          208,090          14,066          13,141            32,847                44           55,019           57,432
Central..........................       46,722,857       2,476,921       2,313,895       225,799,894       134,580,429       96,139,443       96,678,557
Eastern..........................       49,352,278       2,864,175       2,675,660       308,082,858       193,954,812      119,349,692      119,920,136
Pacific..........................          275,775          22,532          21,049         1,788,665           931,985          886,512          889,725
Southern.........................       38,013,636       2,135,219       1,994,682       830,736,198       556,561,957      278,189,127      278,628,229
Western..........................       27,269,499       2,028,785       1,895,254        86,192,896        44,851,904       44,270,821       44,587,803
                                  ----------------------------------------------------------------------------------------------------------------------
    Subtotal.....................      161,842,134       9,541,698       8,913,680     1,452,633,359       930,881,129      538,890,613      540,761,882
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                       Oil and Gas
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan..........................          230,784          11,136          10,403            75,868                53          100,007          102,665

[[Page 70940]]

 
Central..........................        5,254,963         447,260         417,823         8,133,964         3,324,037        5,380,150        5,441,459
Eastern..........................        2,946,199         240,700         224,857         5,775,743         2,726,288        3,368,145        3,402,478
Southern.........................       21,685,085       1,640,611       1,532,629       245,969,418       149,975,760       98,326,228       98,578,405
Western..........................        2,771,305         239,669         223,894         4,717,343         1,903,145        3,115,295        3,147,643
                                  ----------------------------------------------------------------------------------------------------------------------
    Subtotal.....................       32,888,335       2,579,376       2,409,606       264,672,336       157,929,282      110,289,825      110,672,651
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                              Postal and Delivery Services
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan..........................          223,989          27,487          25,678            64,174                 2           89,319           91,966
Central..........................       10,250,664       1,189,567       1,111,272        12,828,157         4,937,878        9,034,302        9,155,164
Eastern..........................       13,819,885       1,517,304       1,417,437        23,773,311        11,087,251       14,219,778       14,382,377
Pacific..........................          144,635          16,201          15,134           465,869           185,834          296,118          297,821
Southern.........................       10,090,918       1,136,067       1,061,293        58,865,833        34,096,163       25,892,369       26,011,207
Western..........................        5,829,356         736,437         687,966         9,319,823         3,668,631        6,307,770        6,376,742
                                  ----------------------------------------------------------------------------------------------------------------------
    Subtotal.....................       40,359,447       4,623,062       4,318,780       105,317,166        53,975,760       55,839,656       56,315,277
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                Recreation and Amusement
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan..........................          210,864          20,358          19,018            57,466                 3           80,585           83,055
Central..........................        9,811,950         843,376         787,866        17,877,387         7,852,494       11,090,426       11,204,934
Eastern..........................       15,803,455       1,264,869       1,181,617        39,502,426        19,982,691       21,226,567       21,410,624
Pacific..........................          200,532          15,892          14,846           963,577           406,550          578,670          581,005
Southern.........................       10,826,402         823,464         769,265       122,043,421        73,576,662       49,631,746       49,757,665
Western..........................        8,194,447         700,718         654,598        18,758,186         8,218,151       11,429,552       11,525,169
                                  ----------------------------------------------------------------------------------------------------------------------
    Subtotal.....................       45,047,650       3,668,678       3,427,212       199,202,463       110,036,551       94,037,545       94,562,450
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                              Sanitation and Waste Removal
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan..........................           33,469           2,039           1,905             9,981                 7           13,525           13,912
Central..........................        1,117,336          84,368          78,815         3,783,722         1,935,236        1,968,656        1,981,649
Eastern..........................        1,797,476         120,671         112,729         8,449,281         4,735,129        3,905,966        3,926,808
Pacific..........................           29,262           1,783           1,666           305,303           153,166          155,241          155,580
Southern.........................        1,367,533          87,530          81,769        26,837,577        16,888,684       10,094,399       10,110,239
Western..........................          831,250          58,708          54,844         3,257,159         1,581,133        1,765,022        1,774,672
                                  ----------------------------------------------------------------------------------------------------------------------
    Subtotal.....................        5,176,326         355,099         331,727        42,643,022        25,293,354       17,902,810       17,962,860
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                   Telecommunications
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan..........................           64,849           5,117           4,780            21,032                14           28,014           28,769
Central..........................        3,579,895         311,005         290,535        12,308,820         6,509,796        6,188,114        6,229,906
Eastern..........................        5,274,999         425,661         397,645        25,792,488        14,993,199       11,369,355       11,430,805
Pacific..........................           59,652           4,637           4,332           544,081           280,645          269,865          270,559
Southern.........................        4,687,346         373,919         349,308        79,412,836        50,846,902       29,072,061       29,126,648
Western..........................        2,724,734         260,838         243,670         9,652,087         4,891,989        5,058,656        5,090,561
                                  ----------------------------------------------------------------------------------------------------------------------
    Subtotal.....................       16,391,476       1,381,178       1,290,271       127,731,345        77,522,545       51,986,066       52,177,248
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                 Temporary Help Services
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan..........................           16,876           1,220           1,139             4,988                 4            6,794            6,990
Central..........................        9,875,319         230,862         215,667        51,592,972        28,479,694       24,123,896       24,236,673
Eastern..........................       13,317,760         325,305         303,894       112,624,291        69,170,634       44,817,963       44,970,108
Pacific..........................          285,783           3,117           2,912         4,508,995         2,418,741        2,119,144        2,122,393
Southern.........................       20,047,132         276,225         258,044       713,170,489       471,523,566      243,679,259      243,907,428
Western..........................       10,232,846         198,451         185,389        61,162,815        32,737,109       29,468,836       29,585,532
                                  ----------------------------------------------------------------------------------------------------------------------
    Subtotal.....................       53,775,715       1,035,180         967,046       943,064,551       604,329,748      344,215,893      344,829,125
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                     Transportation
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan..........................          705,899          65,875          61,539           204,688                41          281,825          290,083
Central..........................       39,276,702       4,098,420       3,828,669        55,353,625        22,046,506       37,644,631       38,105,890
Eastern..........................       37,285,875       3,738,797       3,492,716        69,982,708        32,796,689       41,288,487       41,725,758
Pacific..........................          586,991          46,755          43,678         3,804,184         1,787,980        2,079,579        2,086,415
Southern.........................       39,677,412       3,803,184       3,552,865       299,605,425       175,255,496      128,697,989      129,162,606
Western..........................       17,327,009       2,706,608       2,528,464        34,566,152        15,385,219       21,184,295       21,391,375
                                  ----------------------------------------------------------------------------------------------------------------------
    Subtotal.....................      134,859,888      14,459,640      13,507,932       463,516,783       247,271,929      231,176,806      232,762,128
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                        Utilities
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan..........................          148,444          12,671          11,837            56,132                17           72,227           73,959
Central..........................        7,146,656         575,888         537,984        26,352,196        13,657,174       13,467,276       13,550,526
Eastern..........................        9,587,651         712,199         665,323        48,962,091        27,538,893       22,453,183       22,564,626
Pacific..........................           62,534           6,067           5,668           408,852           201,198          214,514          215,247
Southern.........................       10,044,588         839,241         784,004       157,131,720        98,366,742       59,853,362       59,970,488

[[Page 70941]]

 
Western..........................        4,579,887         434,070         405,500        16,308,986         7,985,486        8,824,896        8,878,506
                                  ----------------------------------------------------------------------------------------------------------------------
    Subtotal.....................       31,569,760       2,580,136       2,410,316       249,219,978       147,749,511      104,885,457      105,253,352
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                       Warehousing
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan..........................           23,861           3,648           3,407             8,026                 1           10,776           11,060
Central..........................        5,061,913         533,106         498,018        15,543,866         8,175,173        7,928,195        7,987,661
Eastern..........................        7,009,792         674,099         629,731        29,673,913        17,101,945       13,340,358       13,422,450
Pacific..........................           61,662           8,558           7,994           251,578           110,383          148,218          148,950
Southern.........................        6,441,787         661,753         618,198        81,655,479        52,136,892       30,228,941       30,304,551
Western..........................        4,325,559         500,559         467,613        11,931,088         5,614,252        6,799,447        6,850,443
                                  ----------------------------------------------------------------------------------------------------------------------
    Subtotal.....................       22,924,573       2,381,722       2,224,961       139,063,951        83,138,646       58,455,935       58,725,115
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                        Non-Core
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan..........................        5,182,429         456,951         426,875         1,764,690               644        2,327,985        2,388,511
Central..........................      391,224,691      38,434,798      35,905,088       868,489,307       403,322,044      508,133,212      512,718,138
Eastern..........................      667,495,610      60,452,354      56,473,487     2,079,644,665     1,107,489,644    1,044,949,817    1,052,751,986
Pacific..........................        9,892,196         891,014         832,369        54,062,267        24,745,067       30,395,521       30,511,129
Southern.........................      450,564,899      48,351,398      45,168,995     3,787,838,223     2,278,523,483    1,559,206,369    1,564,503,073
Western..........................      371,580,343      38,699,763      36,152,613       906,764,875       401,438,741      546,354,145      550,717,629
                                  ----------------------------------------------------------------------------------------------------------------------
    Subtotal.....................    1,895,940,169     187,286,279     174,959,427     7,698,564,027     4,215,519,623    3,691,367,049    3,713,590,466
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                          Total
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan..........................       10,459,352         858,832         802,306         3,093,451             1,069        4,224,201        4,346,103
Central..........................      781,525,250      67,561,332      63,114,565     1,853,564,488       912,457,660    1,026,015,486    1,035,137,646
Eastern..........................    1,178,819,653      98,930,485      92,419,056     3,799,935,917     2,079,382,329    1,848,328,601    1,862,076,179
Pacific..........................       17,291,605       1,442,349       1,347,416       103,809,082        49,156,476       56,526,001       56,727,623
Southern.........................      905,182,777      80,937,580      75,610,412     9,992,060,191     6,199,237,788    3,891,434,439    3,902,010,703
Western..........................      647,433,093      63,782,331      59,584,291     1,649,953,684       765,300,091      955,775,136      963,363,384
                                  ----------------------------------------------------------------------------------------------------------------------
        Total....................    3,540,711,730     313,512,910     292,878,045    17,402,416,812    10,005,535,413    7,782,303,863    7,823,661,638
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source: OSHA estimate.
\a\ The total costs with cost savings accounts for the potential labor productivity loss avoided by having more efficient and effective rest breaks
  required by the proposed standard than are currently taken.


                                           Table VIII.C.29--Total Costs of the Proposed Standard by Provision
                                                                         [2023$]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                       Periodic costs annualized                                              Total annualized \a\
            Provision                  One-time    --------------------------------      Annual         Costs savings  ---------------------------------
                                                          0%              2%                                                   0%               2%
--------------------------------------------------------------------------------------------------------------------------------------------------------
Rule Familiarization.............     $153,433,817              $0              $0                $0                $0      $15,343,382      $17,081,254
Heat Injury and Illness                996,730,462               0               0       173,783,056                 0      273,456,102      284,745,597
 Prevention Plan.................
Identifying Heat Hazards.........       71,768,226     313,512,910     292,878,045       367,833,244                 0      406,361,358      408,428,047
Requirements at or above the           563,572,187               0               0     1,530,484,155        87,542,404    1,499,298,970    1,505,682,286
 Initial Heat Trigger............
Requirements at or above the High        4,451,329               0               0    14,222,455,144     9,917,993,009    4,304,907,268    4,304,957,686
 Heat Trigger....................
Heat Illness and Emergency             276,228,782               0               0       626,032,515                 0      653,655,393      656,784,106
 Response and Planning...........
Training.........................    1,474,526,928               0               0       481,828,698                 0      629,281,391      645,982,661
                                  ----------------------------------------------------------------------------------------------------------------------
    Total........................    3,540,711,730     313,512,910     292,878,045    17,402,416,812    10,005,535,413    7,782,303,863    7,823,661,638
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source: OSHA estimate.
\a\ The total costs with cost savings accounts for the potential labor productivity loss avoided by having more effective rest breaks required by the
  proposed standard than are currently taken.

VI. Sensitivity Analysis
    In this section, OSHA presents the results of five sensitivity 
analyses where isolated changes were made to the parameter (cost model 
inputs) assumptions that were used to estimate the total costs of the 
proposed standard. The methodology and calculations underlying the 
estimates of the costs are generally linear and additive in nature. 
Thus, the sensitivity of the results and conclusions of this analysis 
will generally be proportional to isolated variations of a particular 
input parameter. For example, if the estimated time that an employee 
spends in annual training was doubled, the corresponding labor costs 
would double as well.
    OSHA evaluated a series of five such changes in cost input 
parameters to illustrate how these adjustments would impact the 
estimated total costs of the proposed standard. The requirements of the 
proposed standard work collectively to produce the benefit of avoided 
HRIs and heat-related fatalities. The agency is unable to directly 
attribute avoided

[[Page 70942]]

HRIs and heat-related fatalities to any specific provision so is unable 
to analyze the impact that these isolated changes to parameters might 
have on benefits.
    In the first of five sensitivity tests, OSHA decreased the 
estimated percentage of buildings with adequate cooling, which is an 
input into calculating the number of indoor in-scope firms and 
establishments. For this analysis, OSHA reduced the number of buildings 
that are cooled under an assumption that all employees work in areas 
that are adequately cooled only if at least 70 percent of their 
floorspace cooled (versus the assumption that this condition is met 
when at least 50 percent of the floorspace is cooled). OSHA used 60 
percent of the percentage of buildings with 51 to 99 percent of 
floorspace cooled according to CBECS data for 2018 plus the percentage 
of buildings with 100 percent of floorspace cooled to estimate the 
percentage of establishments that are adequately cooled under this 
sensitivity analysis. For example, if the percentage of buildings with 
51 to 99 percent of floorspace cooled is 25 percent and the percentage 
of buildings with 100 percent of floorspace cooled is 50 percent, the 
estimate used in the primary cost analysis is 75 percent of buildings 
where all employees work in spaces that are adequately cooled, while 
the sensitivity analysis assumes that the percentage is 65 percent. 
Table VIII.C.30. shows that the estimated costs of compliance would 
increase costs by $585 million annually, or by about 7.5 percent.
    In the second sensitivity test, OSHA decreased the estimated non-
compliance rates (i.e., assumed higher baseline compliance) for rest 
breaks at both heat triggers by half. OSHA included this sensitivity 
test due to uncertainty surrounding the assumptions regarding the 
current provision of rest breaks by employers for non-heat related 
reasons (e.g., union contracts, existing State laws) that may result in 
an underestimate of baseline compliance. As a result of this 
adjustment, estimated annualized total costs decreased by nearly $2.1 
billion annually, or approximately 27.0 percent (see table VIII.C.30.).
    In the third sensitivity test, OSHA assumed that all employers 
without an existing HIIPP will opt to use the OSHA provided template to 
develop their HIIPP, rather than a portion of establishments opting to 
write a HIIPP from scratch. Table VIII.C.30. shows that this assumption 
would lower the estimate annualized costs by $7.8 million, or about 0.1 
percent.
    For the fourth sensitivity analysis, OSHA increased the estimated 
travel time to rest breaks by one minute for employees working indoors 
and two minutes for employees working outdoors, thus increasing travel 
time to 3 minutes for indoor employees and 6 minutes for outdoor 
employees. As shown in table VIII.C.30., the increase in travel time to 
rest breaks would increase estimated annualized costs by approximately 
$1.4 billion, or by about 18.1 percent.
    The final sensitivity test looks at the percent of productivity 
recovered as a result of rest breaks. OSHA has incorporated the 
potential cost reduction from decreased worker pacing--offsetting about 
70 percent of the labor cost of rest breaks.\80\ However, this analysis 
rests on specific assumptions and is dependent on the extent of the 
available literature, in which heat and productivity were assessed in 
different settings with different break policies, but break policies 
did not vary within the same setting. An alternative calculation, 
provided in appendix A, suggests that this offset may be even greater--
up to 100 percent of the time spent for rest breaks being recovered 
through improved labor productivity.\81\ Assuming that scheduled rest 
breaks offset pacing 100 percent for workers above the high heat 
trigger, the cost of this proposed standard would decrease by about 
$2.5 billion making the total costs around $7.8-$2.5 = $5.3 billion.
---------------------------------------------------------------------------

    \80\ See Section VIII.C.VI., Sensitivity Analysis for a 
discussion of potential underestimation of levels of current 
compliance with the rest break requirements of the proposed standard 
and the impacts alternative noncompliance rates might have on the 
estimated costs of the proposed standard.
    \81\ As described in the discussion of additional unquantified 
potential benefits, a reduction of pacing from increased rest breaks 
could potentially increase production and revenue.
---------------------------------------------------------------------------

    OSHA welcomes input from the public regarding all aspects of this 
sensitivity analysis, including any data or information regarding the 
accuracy of the preliminary estimates of compliance costs and benefits 
and how the estimates of costs may be affected by varying assumptions 
and methodological approaches.

         Table VIII.C.30--Results From Sensitivity Analyses of Isolated Changes to Cost Model Parameters
----------------------------------------------------------------------------------------------------------------
                                                                                     Percentage      Adjusted
       Impact variable          OSHA's primary    Sensitivity        Impact to       impact to      annualized
                                   estimate     test assumption   annualized costs     costs          costs
----------------------------------------------------------------------------------------------------------------
Percentage of buildings        Using CBECS      Using CBECS           $585,344,087         7.48   $8,409,005,725
 cooled by industry.            data,            data,
                                considered all   considered
                                buildings with   buildings with
                                at least 51      70 percent of
                                percent of       floorspace
                                floorspace       cooled as
                                cooled as        adequately
                                adequately       cooled.
                                cooled.
Rest break non-compliance      As detailed in   Reduce the          -2,113,058,097       -27.01    5,710,603,541
 rates.                         table            rates in table
                                VIII.C.3. Rest   VIII.C.3. Rest
                                Break Non-       Break Non-
                                Compliance       Compliance
                                Rates by State   Rates by State
                                and Territory.   and Territory
                                                 by 50 percent
                                                 (i.e., assume
                                                 higher
                                                 baseline
                                                 compliance).
Percentage of establishments   90 percent of    100% of all             -7,832,568        -0.10    7,815,829,070
 without existing HIIPP that    all employers    employers.
 will use OSHA template.        with more than
                                10 employees,
                                all employers
                                with 10 or
                                less employees.
Travel time to/from rest       2 minutes for    3 minutes for        1,418,460,548        18.13    9,242,122,186
 break area.                    indoor and 4     indoor and 6
                                minutes for      minutes for
                                outdoor.         outdoor.
Recovered break time through   ~70% of break    100% of break        2,500,000,000  ...........    5,300,000,000
 improved productivity.         time offset by   time offset by
                                increased        increased
                                productivity.    productivity.
----------------------------------------------------------------------------------------------------------------
Source: OSHA estimate.


[[Page 70943]]

D. Economic Feasibility

I. Introduction
    As explained in Section II., Pertinent Legal Authority, to 
demonstrate that a standard is economically feasible, ``OSHA must 
construct a reasonable estimate of compliance costs and demonstrate a 
reasonable likelihood that these costs will not threaten the existence 
or competitive structure of an industry, even if it does portend 
disaster for some marginal firms.'' Lead I, 647 F.2d at 1272. OSHA 
standards therefore satisfy the economic feasibility criterion so long 
as they do not cause massive economic dislocations within a particular 
industry or imperil the very existence of the industry. Lead II, 939 
F.2d at 980; see also Asbestos I, 499 F.2d. at 478.
    In this feasibility analysis, when OSHA speaks of the costs of 
complying with the proposed standard as a percent of revenues, it is 
referring to the costs of complying with 29 CFR 1910.148 for the subset 
of those establishments that will incur obligations under the proposed 
standard, as opposed to the costs as a percent of all establishments in 
an industry, whether they are directly affected or not. This avoids 
underestimating the average per-establishment cost used in the 
feasibility analysis, even while it may overstate the impact on the 
industry as a whole. Based on the analysis below, OSHA preliminarily 
concludes that the proposed standard is economically feasible.
II. OSHA's Screening Test for Economic Feasibility
    To determine whether a standard is economically feasible, OSHA 
typically begins by using a screening test to determine whether the 
costs of the standard are beneath the threshold level at which the 
economic viability of an affected industry might be threatened. The 
screening test is a revenue test. While there is no firm rule on which 
to base the threshold, OSHA generally considers a standard to be 
economically feasible for an affected industry when the annualized 
costs of compliance are less than one percent of annual revenues for 
the average establishment in an industry that incurs an obligation. The 
one-percent revenue threshold is intentionally set at a low level so 
that OSHA can confidently assert that the standard is economically 
feasible for industries that are below the threshold (i.e., industries 
for which the costs of compliance are less than one percent of annual 
revenues). To put the one percent threshold into perspective, across 
the wide swath of affected industries, prices (and therefore revenues), 
particularly in the recent past, are generally observed to change by 
considerably more than one percent per year.82 83
---------------------------------------------------------------------------

    \82\ For data on Consumer Price Index (CPI) changes over time, 
see BLS's CPI website at https://www.bls.gov/cpi/.
    \83\ For data on Producer Price Index (PPI) changes over time, 
see BLS's PPI website at https://www.bls.gov/ppi/.
---------------------------------------------------------------------------

    Another and less reliable screening test that OSHA traditionally 
used to consider whether a standard is economically feasible for an 
affected industry is whether the costs of compliance are less than ten 
percent of annual profits for the average establishment (see, e.g., 
OSHA's economic analysis of its 2016 Occupational Exposure to 
Respirable Crystalline Silica (Silica) rulemaking, 81 FR 16286, 16533 
(Mar. 25, 2016); upheld in N. Am.'s Bldg. Trades Unions v. OSHA, 878 
F.3d 271, 300 (D.C. Cir., 2017)). The ten-percent profit test was 
intended to be at a sufficiently low level to allow OSHA to identify 
industries that might require further examination. Specifically, the 
profit screening was primarily used to alert OSHA to potential impacts 
on industries where demand does not allow for ready absorption of new 
costs (e.g., industries with foreign competition where the American 
firms would incur costs that their foreign competitors would not 
because they are not subject to OSHA requirements). In addition, 
setting the threshold for the profit test low provided an additional 
basis for concluding that the standard would be economically feasible 
for industries below that threshold, without further evaluation. OSHA 
notes that this profit screen relied on accounting profit (revenues 
minus explicit costs) versus the superior profit measurement of 
economic profit (revenues minus explicit costs minus implicit costs).
    For this proposed standard, OSHA has discontinued the use of its 
profit screening test for the following reasons. First, OSHA has been 
virtually alone among Federal agencies in consistently using a 
profitability test (comparing costs to profits) as part of its 
regulatory impact analyses. The agency could find no evidence that 
other Federal regulatory agencies are being asked to examine 
feasibility based on profits. OSHA infers that the silence on the use 
of the profitability test among all other Federal regulatory bodies 
implies that the revenue test is sufficient. Even OSHA's sister agency, 
the Mine Safety and Health Administration (MSHA), does not rely on a 
profitability test despite very similar statutory language that also 
requires an economic feasibility determination for its regulations.\84\
---------------------------------------------------------------------------

    \84\ The Mine Act instructs the Secretary to ``set standards 
which most adequately assure on the basis of the best available 
evidence that no miner will suffer material impairment of health or 
functional capacity.'' 30 U.S.C. 811(a)(6)(A). It goes on to say 
that ``[i]n addition to the attainment of the highest degree of 
health and safety protection for the miner, other considerations 
shall be . . . the feasibility of the standards.''
---------------------------------------------------------------------------

    Secondly, eliminating the profit test avoids OSHA's reliance on 
published IRS corporate net income data that lack transparency, 
comprehensive coverage within industries, and statistical reliability 
for industries where sample sizes may be statistically inadequate. 
Furthermore, because firms typically have an incentive to minimize 
their tax burden, it is reasonable to expect that some of the reported 
accounting data may have been strategically adjusted to reduce reported 
profits and their associated tax implications. Business profits are 
much more likely to reflect such strategic accounting than business 
revenues. It is therefore unsurprising that OSHA is the lone outlier by 
including profit screens in its economic analysis. As the Environmental 
Protection Agency (EPA) noted in its economic impact analysis 
supporting the National Air Emission Standards for Hazardous Air 
Pollutants: Halogenated Solvent Cleaning (72 FR 25138 (May 3, 2007)) 
\85\, when explaining its reliance on a ``sales test'' (revenue) and 
rejecting the use of industry profits as part of its determination of 
the impact of its regulation on small businesses, ``revenues or sales 
data is commonly available data for entities normally impacted by EPA 
regulations and profits data normally made available is often not the 
true profits earned by firms due to accounting and tax 
considerations.'' EPA also noted that ``firms and entities often have 
ways available in the tax code to reduce their reported profits; thus, 
using reported profits may lead to an overestimate of the economic 
impact of a regulation to an affected firm or entity and their 
consumers.'' OSHA is aware of no other publicly available source of 
business income data.
---------------------------------------------------------------------------

    \85\ Available at https://www.epa.gov/sites/default/files/2020-07/documents/halogenated-solvent_eia_neshap_final_05-2007.pdf.
---------------------------------------------------------------------------

    Even to the extent that firms are not manipulating profit data for 
tax purposes, profit data are often not accurately aligned with a 
firm's financial status for purposes of evaluating the economic impact 
of an OSHA standard. For example, a firm that had already invested a 
significant amount of capital to voluntarily adopt all of the controls 
proposed by OSHA's

[[Page 70944]]

standard could show only marginal profit after accounting for those 
expenses, suggesting that it would be economically infeasible for that 
firm to comply with OSHA's standard. Yet, in reality, its ability to 
comply with OSHA's standard could not be questioned because compliance 
had already been accomplished.
    OSHA is required to make its determinations on the best available 
evidence, and OSHA's experience has been that the profit screen has 
amounted to little more than a distraction that unhelpfully flags 
industries for time-consuming analyses, while not actually aiding the 
agency in identifying industries for which standards would be 
economically infeasible. For example, the profit screen can produce the 
unhelpful result of flagging industries with significant numbers of 
nonprofit or not-for-profit organizations, as well as failing (at least 
for tax purposes) enterprises reporting negative profits. The revenue 
screen is obviously more useful for evaluating the economic impact of 
the standard on such entities.
    Another example of the inefficiency of the profit screen is that it 
often requires OSHA to manipulate data to adjust for the underlying 
limitations of the profit data sources to perform the screening 
analysis at all. If significant adjustments are necessary, the result 
becomes less meaningful. As a case in point, this proposed standard 
would affect nineteen 4-digit NAICS industries in the Agriculture, 
Forestry, Fishing and Hunting sector (NAICS 11). No profit data are 
available at the 4-digit level for any of the 19 industries, and, since 
2013, about half of the profit data at the 3-digit level are missing. 
OSHA's traditional process for adjusting data to perform the profit 
screen is to substitute data from the next highest level of NAICS codes 
(focusing on a broader swath of industries). In order for OSHA to 
include these industries in a profit screen for this rulemaking, OSHA 
would have had to apply the 2-digit profit rate to all 19 industries, 
which are as different as logging and aquaculture with the result 
potentially flagging economic distress for one industry that is 
actually the result of more drastic economic problems in an entirely 
different industry (e.g., flagging impacts on aquaculture that would 
actually result from a decrease in logging profits).
    OSHA also notes that it gathers additional information about 
potential economic impacts directly from small not-for-profit entities 
and small businesses as part of its compliance with the Small Business 
Regulatory Enforcement Fairness Act (SBREFA), discussed in more detail 
later in this analysis. OSHA is one of only a handful of agencies 
required to engage in this process, which along with the opportunity 
for public comment on proposed standards and the accompanying economic 
analysis, provides an additional avenue for the agency to identify 
potential significant economic impact not flagged via the revenue 
screen. Avoiding the red herrings produced by the profit screen allows 
the agency to focus its resources on areas where the best evidence 
indicates that a standard may truly pose economic feasibility issues 
for an industry.
    Third, compounding underlying issues with profit reporting is the 
reality that current IRS data are measurably different and inferior to 
pre-2013 IRS profit data because the more recent data are presented at 
a more aggregated level (e.g., at the 2-digit rather than 6-digit NAICS 
level). These changes to the IRS data make them incompatible with 
performing this type of screening analysis. Up to this point, where 
OSHA presented a profit screening analysis, the agency was relying on 
data from 2003 through 2013. At this point, it is difficult to assume 
that profit data from those years are meaningfully representative of 
current industry activity. Accordingly, revenues are a more accurate 
measure than profits for evaluating economic feasibility and those data 
are regularly collected and reported by agencies such as the Census 
Bureau. Therefore, the appropriate economic feasibility test will be 
the revenue test for most or all covered industries.
    OSHA judges that the revenue test can stand alone in playing the 
signaling role that it has long served in tandem with the profit 
screen, given the latter's increasing unreliability. That is, a 
standard is not necessarily judged economically infeasible for the 
industries that do not pass the initial revenue screening test (i.e., 
those for which the costs of compliance with the standard are one 
percent or more of annual revenues) nor did previous OSHA analyses 
declare a standard infeasible based on one or more industries failing 
the profit screening test. Instead, OSHA normally views industries 
failing one or both tests as requiring additional examination as to 
whether the standard would be economically feasible (see N. Am.'s Bldg. 
Trades Unions v. OSHA, 878 F.3d at 297). OSHA therefore conducts 
further analysis of the industries that ``fail'' the screening tests to 
evaluate whether the standard would threaten the existence or 
competitive structure of those industries (see United Steelworkers of 
Am., AFL-CIO-CLC v. Marshall, 647 F.2d 1189, 1272 (D.C. Cir. 1980)) and 
the agency will continue to do so for industries that fail the revenue 
screening test. There are fluctuations of prices over time with a 
general inflationary long-term trend upward, and they include effects 
such as the pass-through of costs and modifications in tax accounting 
procedures. Using the cost-to-profit test has never led to the 
conclusion that a standard will eliminate an industry or significantly 
alter its competitive structure, and as described above, that test is 
increasingly limited given the lack of data available. Instead, the 
revenue test is sufficient to signal to OSHA where it should look more 
carefully at one or more industries to assess feasibility.
III. Time Parameters for Analysis
    OSHA's economic analyses almost always measure the costs of a 
standard on an annual basis, conducting the screening tests by 
measuring the cost of the standard against the annual revenues for a 
given industry. One year is typically the minimum period for evaluating 
the status of a business; for example, most business filings for tax or 
financial purposes are annual in nature.
    Some compliance costs are up-front costs and others are spread over 
the duration of compliance with the standard; regardless, the costs of 
the standard overall will not typically be incurred or absorbed by 
businesses all at once. For example, the initial capital costs for 
equipment that will be used over many years are typically addressed 
through installments over a year or more to leverage loans or payment 
options to allow more time to marshal revenue and minimize impacts on 
reserves.
    This proposed standard would include permanent requirements to 
protect employees from hazards of heat stress in the workplace. Thus, 
for this proposed standard, OSHA has based its analysis of economic 
feasibility on annual costs and revenues. As noted earlier in this 
feasibility analysis, this is consistent with OSHA's typical 
methodology for analyzing economic feasibility (e.g., OSHA's final 
Silica rule, 81 FR 16533).
IV. Data Used for the Feasibility Screening Test
    OSHA presents the estimated costs of complying with this proposed 
standard in Costs of Compliance (Section VIII.C., Costs of Compliance) 
and table VIII.D.1. in this section presents a summary of those costs, 
including average cost per establishment and total annual costs, by

[[Page 70945]]

4-digit NAICS code. OSHA relies on these estimated costs in its 
examination of feasibility, using the test described above.
    Most revenue numbers used to determine cost-to-revenue ratios were 
obtained from the 2017 SUSB (Census Bureau, 2021a). This is the most 
current information available from this source, which OSHA considers to 
be the best available source of revenue data for U.S. businesses. OSHA 
adjusted these figures to 2023 dollars using the Bureau of Economic 
Analysis's GDP deflator (BEA, n.d.), which is OSHA's standard source 
for inflation and deflation analysis (See Section VIII.C., Costs of 
Compliance for a full discussion of data sources and methodology). For 
industries that are unavailable in the SUSB dataset, OSHA sourced 
revenue data from a variety of other sources. These industries are 
listed below, along with the alternative sources and methods for 
estimating annual revenues.
    Agriculture: As most agricultural industries are not included in 
the SUSB dataset,\86\ OSHA used the Department of Agriculture's 2017 
Census of Agriculture (USDA, 2017) to derive estimates of annual 
revenues. Specifically, OSHA used industry-level estimates of ``total 
sales'' from chapter 1, table 75 ``Summary by North American Industry 
Classification System'' to represent annual revenues. Since these 
``total sales'' data are combined for Aquaculture (NAICS 1125) and 
Other Animal Production (NAICS 1129), OSHA based NAICS 1125 revenues on 
NOAA Fisheries' Aquaculture website, which estimated U.S. aquaculture 
production at $1.5 billion (NOAA, 2023a). For NAICS 1129, OSHA 
subtracted this $1.5 billion from the Agriculture Census ``total 
sales'' estimate for NAICS 1125 and 1129. OSHA adjusted these figures 
to 2023 dollars using the BEA's GDP deflator.
---------------------------------------------------------------------------

    \86\ The NAICS industries that were estimated using this method 
are Oilseed and Grain Farming (111100), Vegetable and Melon Farming 
(111200), Fruit and Nut Tree Farming (111300), Greenhouse, Nursery, 
and Floriculture (111400), Other Crop Farming (111900), Cattle Ranch 
and Farming (112100), Hog and Pig Farming (112200), Poultry and Egg 
Production (112300), Sheep and Goat Farming (112400), Aquaculture 
(112500), and Other Animal Production (112900).
---------------------------------------------------------------------------

    Local Government: OSHA relied on data from three alternative 
sources for local government estimates. To estimate total receipts for 
local government entities, OSHA first estimated the average annual 
receipts per resident by State. The estimate was equal to the ratio of 
total local government receipts in the datasets found in the Census 
Bureau's 2021 Annual Survey of State and Local Government Finances 
(Census Bureau, 2023a) to the total population served in the GUS 
dataset. OSHA then multiplied the population associated with each 
government entity captured in the GUS with the ratio from step one to 
arrive at an estimate of total annual receipts per government entity.
    State Government: OSHA used the State government revenues estimated 
in the Census Bureau's 2021 Annual Survey of State and Local Government 
Finances (Census Bureau, 2023a) to estimate annual receipts for State 
governments. For U.S. territories, OSHA used point estimates from other 
sources (American Samoa Department of Commerce, 2021; Guam Governor's 
Office, 2024; CNMI Department of Commerce, 2017; Financial Oversight 
and Management Board for Puerto Rico, 2023; USVI's Governor's Office, 
2024). OSHA adjusted these figures to 2023 dollars using the BEA's GDP 
deflator.
    Rail Transportation,\87\  Postal Service, and Insurance and 
Employee Benefit Funds: A small subset of non-agricultural industries 
are also unavailable in the SUSB dataset. These industries are Rail 
Transportation (NAICS 4821), Postal and Delivery Services (NAICS 4911), 
and Insurance and Employment Benefit Funds (NAICS 5251). The economic 
data estimates for these three industries were derived from the 
Quarterly Census of Employment and Wages (QCEW) collected by the Bureau 
of Labor Statistics (BLS). While the QCEW does not present revenue 
data, it does include total annual wages by industry and State. OSHA 
used the ratio of receipts to wages from the SUSB dataset for 
corresponding sector-level data (e.g., the ratio applied to wage data 
for NAICS 5251 is based on receipts and wage data for sector 52 in the 
SUSB dataset) to convert the 2022 QCEW wage data (BLS, 2023f) into 
annual receipts by industry and State.
---------------------------------------------------------------------------

    \87\ The FRA has promulgated regulations requiring the use of 
environmental controls to address heat hazards in three specific, 
limited contexts: non-steam-powered locomotives purchased or 
remanufactured after June 8, 2012 (49 CFR 229.119(g)), camp cars (49 
CFR 228.313(c)), and certain on-track roadway maintenance machines 
(49 CFR 214.505(a)). OSHA's standard would apply to the working 
conditions of railroad employees in all other contexts, including 
within trains and machinery not covered by these regulations and 
during all outdoor work.
---------------------------------------------------------------------------

    A large percentage of the costs of this proposed standard are 
variable costs because they depend primarily on the number and types of 
employees at an establishment. While fixed cost can be more limiting in 
terms of options for businesses, most of the costs of this standard are 
not fixed. Instead, most of the compliance costs vary with the level 
and type of output and employment at an establishment.
    In general, ``[w]hen an industry is subjected to a higher cost, it 
does not simply swallow it; it raises its price and reduces its output, 
and in this way shifts a part of the cost to its consumers and a part 
to its suppliers.'' Am. Dental Ass'n v. Sec'y of Labor, 984 F.2d 823, 
829 (7th Cir., 1993). Increases in prices in industries with elastic 
demand typically result in reduced quantity demanded, but rarely 
eliminate all demand for the product. Increases in costs can also be 
passed along, but with a likely reduction in output.
    A reduction in output could happen in a variety of ways: individual 
establishments could reduce their level of service or production, both 
of which take the form of a reduction of employee hours; some marginal 
establishments could close; or in the case of an industry with high 
turnover of establishments, new entry could be delayed until demand 
equals supply. In many cases, a decrease in overall output for an 
industry will be a combination of all three kinds of reductions. The 
primary means of achieving the reduction in output most likely depends 
on the rate of turnover of establishments in the industry and on the 
form that the costs of the regulation take.
    There are two situations typically mentioned when an industry 
subject to regulatory costs might be unable to pass those costs on: (1) 
foreign competition not subject to the regulation; or (2) domestic 
competition from other firms or other industries, not subject to the 
regulation, that produce goods or services that are close substitutes. 
Otherwise, when all affected domestic industries are covered by a 
standard and foreign businesses must also comply with the standard or 
are unable to compete effectively, the ability of a competing industry 
to offer a substitute product at a lower price is greatly diminished.
V. Factors That Indicate the Ability To Absorb or Pass on the Costs of 
the Proposed Standard
    As discussed above, when all establishments in an affected industry 
are covered by and required to comply with a standard, none of the 
competitors gain any economic advantage from the standard and the 
ability of a competitor to offer a substitute product or service at a 
lower price is greatly diminished. OSHA believes this is the case for 
the industries covered by the proposed standard. The scope of proposed 
29 CFR 1910.148 is broad. The proposed standard applies, with certain 
exceptions, to each setting where any

[[Page 70946]]

employee is exposed to heat above a specified threshold, with the 
result that if an employer enters such a setting, it must comply with 
the standard. Hence, given the proposed standard's broad applicability, 
any employer in a particular industry, including domestic competitors 
providing similar services or goods, would equally be subject to the 
proposed standard. This negates the potential for substitution by an 
industry not subject to the standard.
    In addition, and as discussed below, OSHA has concluded that many 
employers that provide services affected by the proposed standard are 
generally not subject to international competition (e.g., personal 
services, such as child care, healthcare services and healthcare 
support services, and building support services like landscaping and 
maintenance) because they must be performed domestically. Thus, for 
those industries, competition from foreign entities that would not also 
be subject to this proposed standard and its related costs is not a 
factor.
    Finally, while OSHA has attempted to quantify the more obvious cost 
savings associated with compliance with the proposed standard, in terms 
of a wage cost offset from increased labor productivity, there are more 
subtle benefits to reducing heat stress, which suggests that the actual 
net costs of the proposed standard will be lower than the cost 
estimates in Section VIII.C., Costs of Compliance used to demonstrate 
economic feasibility. These cost savings are difficult to quantify and 
include increased labor supply and decreased disutility to employees. 
For additional discussion of this issue, see Section VIII.D., Benefits. 
The economic advantages of increasing the retention of employees by 
reducing peak heat stressors has been noted in numerous articles, and 
while difficult to quantify, would tend to counteract the relatively 
more obvious costs of intervention (e.g., Glaser et al., 2022).
VI. Economic Feasibility Screening Analysis
    This section summarizes OSHA's economic feasibility findings for 
specific industries covered by the proposed standard. As stated 
previously, the agency has historically used the two screening tests 
(costs less than one percent of revenue and costs less than ten percent 
of profit) as an initial indicator of economic feasibility; however, as 
discussed earlier, OSHA has discontinued use of the profit screening 
test because of its serious flaws. In this section, OSHA identifies and 
discusses the industries that fall above the threshold level for the 
revenue screening test. OSHA also identifies and discusses industries 
where small and very small industries fall above the threshold.
A. Economic Feasibility Screening Analysis: All Establishments
    Table VIII.D.1. shows that for the majority of industries, as 
defined by covered NAICS codes, the cost-to-revenue ratios are below 
OSHA's screening threshold of one percent, with an average cost for all 
298 affected industries of 0.04 percent of revenues. This means that if 
the average firm needed to absorb the costs of the standard (rather 
than passing the costs through to other parties), this would amount to 
an additional four cent burden on $100 of revenue and suggests that 
compliance with this proposed standard would be feasible for all of 
these industries.
    Five of the 298 industries are estimated to have costs equal to or 
greater than one percent of revenues. They are all in either 
agriculture or in-person health care or social assistance services. Two 
agricultural industries, Sheep and Goat Farming (NAICS 1124) and Other 
Animal Production (NAICS 1129) were found to have costs above one 
percent of revenues among affected establishments. Three health care 
and social assistance industries, Individual and Family Services (NAICS 
6241), Vocational Rehabilitation Services (NAICS 6243), and Child Care 
Services (NAICS 6244) were also found to have costs above one percent 
of revenues.
    Some industries, such as agriculture, would be expected to have 
relatively large impacts under the proposed standard, due to the 
prevalence of outdoor work. Nonetheless, the costs of their compliance 
with the proposed standard would not generally be expected to exceed 
one percent of revenues when all cost offsets (e.g., current practices 
to address heat hazards, productivity gains outside of rest breaks) are 
considered, based on available empirical evidence. For example, the 
Fair Food Program in Florida (Rivero and Uzcategui, 2024), which 
encompassed a number of labor benefits (e.g., wage bonuses) in addition 
to heat stress protection, resulted in price increases of only one 
extra cent per pound of tomatoes,\88\ for a total average price of 
about $2 per pound,\89\ to cover the cost of the protections and 
benefits to employees. This suggests that the net cost of robust heat 
illness protections may be less than 0.5 percent of revenues in an 
industry and geographic region that would be most significantly 
affected by the proposed standard. Sheep and Goat Farming (NAICS 1124) 
and Other Animal Production (NAICS 1129), which both have costs greater 
than one percent of revenues, are both heavily weighted to very small 
family-owned farms (USDA, 2019). Due to a Congressional budget rider, 
OSHA is not able to expend funds on enforcement activities for small 
farms. Only about 5 percent of sheep and goat farms are something other 
than family-owned farms (i.e., partnerships or corporations). The data 
for other animal production and aquaculture farms are combined and 
reported as a single industry. For those two industries combined, 10 
percent of farms are something other than family-owned farms. Given the 
economies of scale necessary for aquaculture, it's likely that these 
account for more of the corporate farms in the combined Other Animal 
Production and Aquaculture data, meaning more farms in NAICS 1129 may 
be family-owned farms than appear to be in the combined data. Based on 
the 2017 Census of Agriculture (USDA, 2019), about 12,000 of about 
93,000 total sheep and goat farms have hired labor and those have on 
average 2 hired laborers. For other animal production and aquaculture 
combined, about 41,000 farms out of about 222,000 total farms report 
having hired labor and have on average 3 hired laborers. Based on the 
size and organization of these farms, and because a longstanding 
appropriations rider generally prevents OSHA from enforcing its 
standards against most small farm operations with 10 or fewer 
employees, it is unlikely OSHA would enforce the proposed standard in 
those industries.
---------------------------------------------------------------------------

    \88\ This measure is an increase in price, not costs. The pass 
through of costs could be less than 100 percent due to competition. 
However, since a portion of the one-cent premium is used to pay a 
worker bonus, one can infer that the increase in cost of compliance 
is likely less than one-cent and that pass-through of costs to firms 
is greater than 100 percent.
    \89\ As of December 2023, https://fred.stlouisfed.org/series/APU0000712311).
---------------------------------------------------------------------------

    Aside from the issues discussed previously, the agency believes 
some of these industries are unlikely to have as large of a cost as a 
percentage of revenue as presented, in part due to inflexibility in the 
cost analysis regarding the amount of time spent outside in heat in a 
nondiscretionary manner. For example, even if the assumption that 
employees in healthcare or child care services spend a large percentage 
of their time outside is realistic under normal circumstances, these 
employees would likely limit their time outside in high heat situations 
if only to protect

[[Page 70947]]

those in their care. This is also true in livestock industries that 
have existing recommendations for shade and shelter for livestock under 
extreme heat conditions.\90\ If the costs of complying with this 
proposed standard were onerous, limiting employee exposure to the 
outdoors during times of extreme heat would be a costless method to 
comply with the standard and could possibly result in these employers 
being fully exempt from the standard (e.g., if the employer limited 
employee's outdoor exposure to meet the exemption for short duration 
employee exposure). OSHA believes that these five industries have 
estimated costs that exceed one percent of revenue as a result of data 
limitations, rather than a real finding of infeasibility. Therefore, 
OSHA has preliminarily determined that the proposed rule is 
economically feasible.
---------------------------------------------------------------------------

    \90\ USDA guidance for the livestock industry identifies 
provision of shelter, increased shade, and altering plans based on 
heat exposure (https://www.climatehubs.usda.gov/approach/manage-livestock-cope-warmer-and-drier-conditions). Similarly, South Dakota 
State University Extension recommends provision of shade during the 
day, minimization, or avoidance of unnecessary animal work during 
hot time periods, and adequate ventilation and air movement for 
indoor animal housing (https://extension.sdstate.edu/heat-stress-small-ruminants).
---------------------------------------------------------------------------

    The agency welcomes public comment on what the likely practical 
effects of the proposed standard would be in these various industries. 
To the extent commenters believe the proposed standard poses an issue 
of economic feasibility, the agency welcomes comment on how the 
proposed standard should be modified to achieve greater feasibility.

           Table VIII.D.1--Economic Impacts on Establishments Affected by the Proposed Standard With Costs Calculated Using a 2% Discount Rate
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                        Average
                                                                                        Total         annualized     Average revenue     Costs as % of
              NAICS                           Industry             Establishments     annualized       cost per     per establishment       revenue
                                                                                        costs        establishment
--------------------------------------------------------------------------------------------------------------------------------------------------------
1111.............................  Oilseed and Grain Farming....           19,259      $22,566,188          $1,172         $1,039,788               0.11
1112.............................  Vegetable and Melon Farming..            2,635       13,812,142           5,242          1,435,990               0.37
1113.............................  Fruit and Tree Nut Farming...            7,247       20,428,950           2,819            887,377               0.32
1114.............................  Greenhouse, Nursery, and                 3,362       17,437,825           5,186            922,741               0.56
                                    Floriculture Production.
1119.............................  Other Crop Farming...........           12,848       22,027,652           1,714            334,120               0.51
1121.............................  Cattle Ranching and Farming..           24,349       41,972,826           1,724            884,209               0.19
1122.............................  Hog and Pig Farming..........            1,491        3,582,128           2,402          3,692,579               0.07
1123.............................  Poultry and Egg Production...            2,904        6,619,341           2,279          3,595,687               0.06
1124.............................  Sheep and Goat Farming.......            1,995        3,420,215           1,714            109,499               1.57
1125.............................  Aquaculture..................              208          895,579           4,301          1,415,210               0.30
1129.............................  Other Animal Production......            6,404       11,346,005           1,772            143,632               1.23
1131.............................  Timber Tract Operations......              498          726,511           1,459          2,701,023               0.05
1132.............................  Forest Nurseries and                       168          179,247           1,067          1,164,036               0.09
                                    Gathering of Forest Products.
1133.............................  Logging......................            8,084        7,860,331             972          1,692,869               0.06
1141.............................  Fishing......................            2,473        1,185,393             479          1,188,497               0.04
1142.............................  Hunting and Trapping.........              351          374,292           1,066            799,221               0.13
1151.............................  Support Activities for Crop              5,049        7,698,282           1,525          3,457,291               0.04
                                    Production.
1152.............................  Support Activities for Animal            4,765        3,734,295             784            724,524               0.11
                                    Production.
1153.............................  Support Activities for                   1,788        1,775,204             993          1,311,774               0.08
                                    Forestry.
2111.............................  Oil and Gas Extraction.......            6,382       23,921,221           3,748         43,886,186               0.01
2131.............................  Support Activities for Mining           13,313       79,841,646           5,997          7,972,536               0.08
2211.............................  Electric Power Generation,              11,101       80,690,106           7,269         45,828,657               0.02
                                    Transmission and
                                    Distribution.
2212.............................  Natural Gas Distribution.....            2,497       12,578,004           5,037         40,786,387               0.01
2213.............................  Water, Sewage and Other                  4,879       11,985,242           2,456          3,542,449               0.07
                                    Systems.
2361.............................  Residential Building                   173,182      124,444,236             719          2,401,784               0.03
                                    Construction.
2362.............................  Nonresidential Building                 43,061       97,309,378           2,260         13,006,470               0.02
                                    Construction.
2371.............................  Utility System Construction..           19,159      112,079,119           5,850          9,895,873               0.06
2372.............................  Land Subdivision.............            4,943        3,549,637             718          2,247,710               0.03
2373.............................  Highway, Street, and Bridge              9,752       43,581,038           4,469         15,724,180               0.03
                                    Construction.
2379.............................  Other Heavy and Civil                    4,324       11,738,493           2,715          6,787,322               0.04
                                    Engineering Construction.
2381.............................  Foundation, Structure, and              93,258      168,622,817           1,808          2,354,331               0.08
                                    Building Exterior
                                    Contractors.
2382.............................  Building Equipment                     184,768      342,792,872           1,855          2,724,810               0.07
                                    Contractors.
2383.............................  Building Finishing                     116,519      136,463,298           1,171          1,425,684               0.08
                                    Contractors.
2389.............................  Other Specialty Trade                   69,751       97,414,741           1,397          2,689,361               0.05
                                    Contractors.
3111.............................  Animal Food Manufacturing....              895        2,550,666           2,850         35,255,690               0.01
3112.............................  Grain and Oilseed Milling....              369        2,281,901           6,192        106,536,918               0.01
3113.............................  Sugar and Confectionery                    941        3,360,910           3,574         17,901,036               0.02
                                    Product Manufacturing.
3114.............................  Fruit and Vegetable                        916        6,966,483           7,605         43,442,236               0.02
                                    Preserving and Specialty
                                    Food Manufacturing.
3115.............................  Dairy Product Manufacturing..              801        5,315,596           6,640         76,548,651               0.01
3116.............................  Animal Slaughtering and                  1,742       28,278,302          16,233         72,789,500               0.02
                                    Processing.
3117.............................  Seafood Product Preparation                270        1,229,069           4,561         29,356,549               0.02
                                    and Packaging.
3118.............................  Bakeries and Tortilla                    5,847       16,243,920           2,778          6,816,984               0.04
                                    Manufacturing.
3119.............................  Other Food Manufacturing.....            1,887        9,779,813           5,183         33,613,908               0.02
3121.............................  Beverage Manufacturing.......            4,528        9,124,037           2,015         14,142,707               0.01
3122.............................  Tobacco Manufacturing........               69          773,005          11,285        262,563,987               0.00
3131.............................  Fiber, Yarn, and Thread Mills              136        2,067,055          15,199         31,396,792               0.05
3132.............................  Fabric Mills.................              386        2,777,269           7,204         18,720,390               0.04
3133.............................  Textile and Fabric Finishing               402        1,843,098           4,591         10,606,110               0.04
                                    and Fabric Coating Mills.
3141.............................  Textile Furnishings Mills....              818        3,870,400           4,734          9,794,328               0.05
3149.............................  Other Textile Product Mills..            2,022        3,442,371           1,702          2,702,841               0.06
3151.............................  Apparel Knitting Mills.......               89          523,876           5,920          6,382,954               0.09

[[Page 70948]]

 
3152.............................  Cut and Sew Apparel                      2,480        4,006,111           1,616          2,064,640               0.08
                                    Manufacturing.
3159.............................  Apparel Accessories and Other              286          574,129           2,011          2,548,686               0.08
                                    Apparel Manufacturing.
3161.............................  Leather and Hide Tanning and                78          101,034           1,304          7,624,471               0.02
                                    Finishing.
3162.............................  Footwear Manufacturing.......              112          773,050           6,902          8,295,065               0.08
3169.............................  Other Leather and Allied                   364          444,901           1,222          2,105,457               0.06
                                    Product Manufacturing.
3211.............................  Sawmills and Wood                        1,634        7,765,268           4,752         12,001,150               0.04
                                    Preservation.
3212.............................  Veneer, Plywood, and                       670        5,091,443           7,605         19,759,596               0.04
                                    Engineered Wood Product
                                    Manufacturing.
3219.............................  Other Wood Product                       4,904       16,287,680           3,321          5,998,996               0.06
                                    Manufacturing.
3221.............................  Pulp, Paper, and Paperboard                173        6,568,365          37,967        235,901,294               0.02
                                    Mills.
3222.............................  Converted Paper Product                  1,787       12,244,762           6,854         34,990,870               0.02
                                    Manufacturing.
3231.............................  Printing and Related Support            12,693       14,738,174           1,161          3,996,639               0.03
                                    Activities.
3241.............................  Petroleum and Coal Products              1,022        8,724,306           8,541        267,378,536               0.00
                                    Manufacturing.
3251.............................  Basic Chemical Manufacturing.            1,144       11,393,676           9,964        108,368,479               0.01
3252.............................  Resin, Synthetic Rubber, and               681        8,148,929          11,966         91,947,879               0.01
                                    Artificial and Synthetic
                                    Fibers and Filaments
                                    Manufacturing.
3253.............................  Pesticide, Fertilizer, and                 440        1,670,914           3,798         28,466,636               0.01
                                    Other Agricultural Chemical
                                    Manufacturing.
3254.............................  Pharmaceutical and Medicine              1,166       12,270,203          10,528        109,652,940               0.01
                                    Manufacturing.
3255.............................  Paint, Coating, and Adhesive               873        4,187,636           4,800         29,510,337               0.02
                                    Manufacturing.
3256.............................  Soap, Cleaning Compound, and             1,102        5,589,291           5,072         37,391,152               0.01
                                    Toilet Preparation
                                    Manufacturing.
3259.............................  Other Chemical Product and               1,093        4,806,806           4,398         23,897,452               0.02
                                    Preparation Manufacturing.
3261.............................  Plastics Product                         5,149       35,819,947           6,957         22,658,441               0.03
                                    Manufacturing.
3262.............................  Rubber Product Manufacturing.              880        6,058,076           6,888         21,611,316               0.03
3271.............................  Clay Product and Refractory                550        2,002,058           3,640          8,078,807               0.05
                                    Manufacturing.
3272.............................  Glass and Glass Product                    815        4,007,533           4,917         15,793,703               0.03
                                    Manufacturing.
3273.............................  Cement and Concrete Product              4,404       13,765,912           3,126          7,785,632               0.04
                                    Manufacturing.
3274.............................  Lime and Gypsum Product                    118          725,364           6,173         26,805,595               0.02
                                    Manufacturing.
3279.............................  Other Nonmetallic Mineral                1,585        4,779,209           3,016          8,864,633               0.03
                                    Product Manufacturing.
3311.............................  Iron and Steel Mills and                   268        5,962,845          22,291        201,642,290               0.01
                                    Ferroalloy Manufacturing.
3312.............................  Steel Product Manufacturing                318        3,034,850           9,559         38,589,534               0.02
                                    from Purchased Steel.
3313.............................  Alumina and Aluminum                       210        2,605,926          12,409         61,726,946               0.02
                                    Production and Processing.
3314.............................  Nonferrous Metal (except                   389        3,035,679           7,804         61,261,580               0.01
                                    Aluminum) Production and
                                    Processing.
3315.............................  Foundries....................              796        5,296,856           6,654         20,840,709               0.03
3321.............................  Forging and Stamping.........            1,141        4,199,802           3,682         14,958,369               0.02
3322.............................  Cutlery and Handtool                       558        1,274,207           2,286          9,193,550               0.02
                                    Manufacturing.
3323.............................  Architectural and Structural             6,472       23,411,603           3,618          8,360,234               0.04
                                    Metals Manufacturing.
3324.............................  Boiler, Tank, and Shipping                 740        4,557,414           6,163         24,162,652               0.03
                                    Container Manufacturing.
3325.............................  Hardware Manufacturing.......              304        1,285,814           4,230         16,750,859               0.03
3326.............................  Spring and Wire Product                    555        1,725,936           3,110          9,533,258               0.03
                                    Manufacturing.
3327.............................  Machine Shops; Turned                   11,346       16,998,778           1,498          3,557,493               0.04
                                    Product; and Screw, Nut, and
                                    Bolt Manufacturing.
3328.............................  Coating, Engraving, Heat                 2,761        7,251,052           2,626          5,616,834               0.05
                                    Treating, and Allied
                                    Activities.
3329.............................  Other Fabricated Metal                   3,063       12,570,102           4,104         12,315,179               0.03
                                    Product Manufacturing.
3331.............................  Agriculture, Construction,               1,422       10,297,500           7,242         32,127,400               0.02
                                    and Mining Machinery
                                    Manufacturing.
3332.............................  Industrial Machinery                     1,534        4,564,312           2,976         12,175,393               0.02
                                    Manufacturing.
3333.............................  Commercial and Service                     939        3,136,561           3,340         15,121,049               0.02
                                    Industry Machinery
                                    Manufacturing.
3334.............................  Ventilation, Heating, Air-                 842        7,964,382           9,459         29,965,620               0.03
                                    Conditioning, and Commercial
                                    Refrigeration Equipment
                                    Manufacturing.
3335.............................  Metalworking Machinery                   3,159        5,185,713           1,642          6,125,519               0.03
                                    Manufacturing.
3336.............................  Engine, Turbine, and Power                 441        3,614,996           8,197         51,409,099               0.02
                                    Transmission Equipment
                                    Manufacturing.
3339.............................  Other General Purpose                    2,903       13,233,407           4,559         19,613,189               0.02
                                    Machinery Manufacturing.
3341.............................  Computer and Peripheral                    449          841,625           1,877         19,085,845               0.01
                                    Equipment Manufacturing.
3342.............................  Communications Equipment                   614        2,801,459           4,563         31,095,928               0.01
                                    Manufacturing.
3343.............................  Audio and Video Equipment                  227          293,740           1,294          6,807,492               0.02
                                    Manufacturing.
3344.............................  Semiconductor and Other                  1,900        8,118,846           4,273         27,994,372               0.02
                                    Electronic Component
                                    Manufacturing.
3345.............................  Navigational, Measuring,                 2,520       10,704,689           4,248         31,086,340               0.01
                                    Electromedical, and Control
                                    Instruments Manufacturing.
3346.............................  Manufacturing and Reproducing              204          198,879             977          4,335,534               0.02
                                    Magnetic and Optical Media.
3351.............................  Electric Lighting Equipment                501        1,444,609           2,886         13,083,478               0.02
                                    Manufacturing.
3352.............................  Household Appliance                        125        1,066,209           8,530         45,138,353               0.02
                                    Manufacturing.
3353.............................  Electrical Equipment                       995        5,832,098           5,861         21,618,940               0.03
                                    Manufacturing.
3359.............................  Other Electrical Equipment                 977        4,726,132           4,840         22,536,250               0.02
                                    and Component Manufacturing.

[[Page 70949]]

 
3361.............................  Motor Vehicle Manufacturing..              122        1,085,733           8,899        454,487,339               0.00
3362.............................  Motor Vehicle Body and                     944        8,246,263           8,740         29,205,076               0.03
                                    Trailer Manufacturing.
3363.............................  Motor Vehicle Parts                      2,425       27,059,128          11,161         61,631,308               0.02
                                    Manufacturing.
3364.............................  Aerospace Product and Parts                826       12,167,578          14,731         93,792,988               0.02
                                    Manufacturing.
3365.............................  Railroad Rolling Stock                     104        1,429,522          13,812         63,611,383               0.02
                                    Manufacturing.
3366.............................  Ship and Boat Building.......              721       11,788,451          16,361         21,809,920               0.08
3369.............................  Other Transportation                       408        1,037,801           2,547         15,117,084               0.02
                                    Equipment Manufacturing.
3371.............................  Household and Institutional              5,083       13,274,090           2,611          4,297,730               0.06
                                    Furniture and Kitchen
                                    Cabinet Manufacturing.
3372.............................  Office Furniture (including              1,767        5,200,805           2,943          7,971,335               0.04
                                    Fixtures) Manufacturing.
3379.............................  Other Furniture Related                    366        1,792,138           4,903         15,572,532               0.03
                                    Product Manufacturing.
3391.............................  Medical Equipment and                    5,090       13,095,541           2,573         10,884,255               0.02
                                    Supplies Manufacturing.
3399.............................  Other Miscellaneous                      8,780       13,579,420           1,547          4,017,213               0.04
                                    Manufacturing.
4231.............................  Motor Vehicle and Motor                  2,351       26,489,257          11,269         45,407,480               0.02
                                    Vehicle Parts and Supplies
                                    Merchant Wholesalers.
4232.............................  Furniture and Home Furnishing            1,298        9,523,083           7,336         10,625,767               0.07
                                    Merchant Wholesalers.
4233.............................  Lumber and Other Construction            1,736       13,456,090           7,749         13,371,930               0.06
                                    Materials Merchant
                                    Wholesalers.
4234.............................  Professional and Commercial              3,513       25,485,899           7,255         20,295,064               0.04
                                    Equipment and Supplies
                                    Merchant Wholesalers.
4235.............................  Metal and Mineral (except                  958        8,692,950           9,072         27,671,464               0.03
                                    Petroleum) Merchant
                                    Wholesalers.
4236.............................  Household Appliances and                 2,879       28,074,222           9,752         27,451,825               0.04
                                    Electrical and Electronic
                                    Goods Merchant Wholesalers.
4237.............................  Hardware, and Plumbing and               1,951       13,236,652           6,783         11,557,780               0.06
                                    Heating Equipment and
                                    Supplies Merchant
                                    Wholesalers.
4238.............................  Machinery, Equipment, and                5,776       58,234,641          10,082         11,596,411               0.09
                                    Supplies Merchant
                                    Wholesalers.
4239.............................  Miscellaneous Durable Goods              3,188       16,166,409           5,071          9,310,978               0.05
                                    Merchant Wholesalers.
4241.............................  Paper and Paper Product                    967        8,226,081           8,507         19,885,243               0.04
                                    Merchant Wholesalers.
4242.............................  Drugs and Druggists' Sundries            1,019       14,966,530          14,683        110,821,278               0.01
                                    Merchant Wholesalers.
4243.............................  Apparel, Piece Goods, and                1,534        8,083,432           5,269         13,145,411               0.04
                                    Notions Merchant Wholesalers.
4244.............................  Grocery and Related Product              3,517       45,101,982          12,823         34,945,484               0.04
                                    Merchant Wholesalers.
4245.............................  Farm Product Raw Material                  613        4,961,179           8,089         41,951,216               0.02
                                    Merchant Wholesalers.
4246.............................  Chemical and Allied Products             1,223        9,926,609           8,115         23,780,447               0.03
                                    Merchant Wholesalers.
4247.............................  Petroleum and Petroleum                    638        6,705,416          10,506        203,610,923               0.01
                                    Products Merchant
                                    Wholesalers.
4248.............................  Beer, Wine, and Distilled                  451       11,640,093          25,813         43,026,015               0.06
                                    Alcoholic Beverage Merchant
                                    Wholesalers.
4249.............................  Miscellaneous Nondurable                 2,852       20,258,440           7,103         15,167,514               0.05
                                    Goods Merchant Wholesalers.
4251.............................  Wholesale Trade Agents and               3,957       15,142,900           3,827         21,159,691               0.02
                                    Brokers.
4411.............................  Automobile Dealers...........            7,943       70,381,781           8,860         26,031,796               0.03
4412.............................  Other Motor Vehicle Dealers..            2,484       10,727,937           4,319          6,684,856               0.06
4413.............................  Automotive Parts,                       10,382       38,063,251           3,666          2,310,332               0.16
                                    Accessories, and Tire
                                    Retailers.
4441.............................  Building Material and                   10,300       26,774,594           2,599          5,880,598               0.04
                                    Supplies Dealers.
4442.............................  Lawn and Garden Equipment and            3,493       10,491,710           3,003          3,918,834               0.08
                                    Supplies Retailers.
4451.............................  Grocery and Convenience                 16,712      111,429,709           6,668          8,142,684               0.08
                                    Retailers.
4452.............................  Specialty Food Retailers.....            4,575       10,190,815           2,227          2,565,311               0.09
4453.............................  Beer, Wine, and Liquor                   6,050        7,676,768           1,269          2,103,423               0.06
                                    Retailers.
4491.............................  Furniture and Home                       9,532       20,849,798           2,187          3,437,969               0.06
                                    Furnishings Retailers.
4492.............................  Electronics and Appliance                5,359       13,310,629           2,484          3,870,143               0.06
                                    Retailers.
4551.............................  Department Stores............              892       11,243,234          12,610         17,685,253               0.07
4552.............................  Warehouse Clubs,                         9,875       55,995,417           5,670         12,141,433               0.05
                                    Supercenters, and Other
                                    General Merchandise
                                    Retailers.
4561.............................  Health and Personal Care                17,607       26,342,201           1,496          4,568,247               0.03
                                    Retailers.
4571.............................  Gasoline Stations............           18,856       34,130,245           1,810          5,062,894               0.04
4572.............................  Fuel Dealers.................            1,393        2,870,053           2,061          4,568,306               0.05
4581.............................  Clothing and Clothing                   16,339       44,247,522           2,708          2,473,681               0.11
                                    Accessories Retailers.
4582.............................  Shoe Retailers...............            4,397        9,190,469           2,090          2,227,506               0.09
4583.............................  Jewelry, Luggage, and Leather            4,259        6,611,743           1,552          2,704,423               0.06
                                    Goods Retailers.
4591.............................  Sporting Goods, Hobby, and               7,353       16,879,497           2,296          3,294,022               0.07
                                    Musical Instrument Retailers.
4592.............................  Book Retailers and News                  1,515        3,229,542           2,131          2,950,989               0.07
                                    Dealers.
4593.............................  Florists.....................            2,383        4,426,367           1,857          1,442,716               0.13
4594.............................  Office Supplies, Stationery,             5,104       10,013,108           1,962          2,084,249               0.09
                                    and Gift Retailers.
4595.............................  Used Merchandise Retailers...            3,668        7,796,516           2,126          1,521,114               0.14

[[Page 70950]]

 
4599.............................  Other Miscellaneous Retailers            8,050       15,263,208           1,896          2,640,719               0.07
4811.............................  Scheduled Air Transportation.            1,901       25,658,803          13,497         89,545,214               0.02
4812.............................  Nonscheduled Air                         1,825        4,628,067           2,535         11,544,951               0.02
                                    Transportation.
4821.............................  Rail Transportation..........              119          124,334           1,041          2,215,217               0.05
4831.............................  Deep Sea, Coastal, and Great               877        5,042,806           5,750         36,316,671               0.02
                                    Lakes Water Transportation.
4832.............................  Inland Water Transportation..              476        3,118,127           6,552         11,566,749               0.06
4841.............................  General Freight Trucking.....           64,907       89,062,119           1,372          3,024,850               0.05
4842.............................  Specialized Freight Trucking.           42,255       50,978,497           1,206          2,422,016               0.05
4851.............................  Urban Transit Systems........              782        1,541,702           1,972          5,727,178               0.03
4852.............................  Interurban and Rural Bus                   670        1,142,712           1,705          3,183,166               0.05
                                    Transportation.
4853.............................  Taxi and Limousine Service...            6,647        7,550,221           1,136          2,114,168               0.05
4854.............................  School and Employee Bus                  3,712        6,449,362           1,737          2,931,452               0.06
                                    Transportation.
4855.............................  Charter Bus Industry.........            1,069        1,792,372           1,677          3,278,126               0.05
4859.............................  Other Transit and Ground                 4,351        3,709,249             852          1,757,646               0.05
                                    Passenger Transportation.
4861.............................  Pipeline Transportation of                 649        1,410,922           2,174         13,170,788               0.02
                                    Crude Oil.
4862.............................  Pipeline Transportation of               1,812        4,248,289           2,345         15,487,431               0.02
                                    Natural Gas.
4869.............................  Other Pipeline Transportation              580        1,250,571           2,156         14,063,673               0.02
4871.............................  Scenic and Sightseeing                     617        1,320,235           2,139          2,100,659               0.10
                                    Transportation, Land.
4872.............................  Scenic and Sightseeing                   1,554        3,274,995           2,108          1,392,280               0.15
                                    Transportation, Water.
4879.............................  Scenic and Sightseeing                     268          510,004           1,901          2,851,407               0.07
                                    Transportation, Other.
4881.............................  Support Activities for Air               5,046       22,255,588           4,410          5,491,720               0.08
                                    Transportation.
4882.............................  Support Activities for Rail              1,293        4,921,648           3,806          4,754,766               0.08
                                    Transportation.
4883.............................  Support Activities for Water             2,258       11,495,850           5,092          8,269,227               0.06
                                    Transportation.
4884.............................  Support Activities for Road             10,553        8,555,879             811          1,051,046               0.08
                                    Transportation.
4885.............................  Freight Transportation                  18,079       29,423,164           1,627          3,691,452               0.04
                                    Arrangement.
4889.............................  Other Support Activities for             1,434        1,669,460           1,165          1,708,634               0.07
                                    Transportation.
4911.............................  Postal Service...............           25,465       28,299,988           1,111          5,242,980               0.02
4921.............................  Couriers and Express Delivery            8,360       24,629,329           2,946          9,114,393               0.03
                                    Services.
4922.............................  Local Messengers and Local               3,780        3,385,960             896          1,707,066               0.05
                                    Delivery.
4931.............................  Warehousing and Storage......           14,274       58,725,115           4,114          2,766,853               0.15
5121.............................  Motion Picture and Video                 3,012       16,428,008           5,454          5,083,819               0.11
                                    Industries.
5122.............................  Sound Recording Industries...              489        1,147,515           2,346          4,484,294               0.05
5131.............................  Newspaper, Periodical, Book,             3,052       20,020,700           6,559         11,229,220               0.06
                                    and Directory Publishers.
5132.............................  Software Publishers..........            1,821       13,284,155           7,296         25,213,904               0.03
5161.............................  Radio and Television                       778        9,163,332          11,786          8,807,054               0.13
                                    Broadcasting Stations.
5162.............................  Media Streaming Distribution               533        6,637,578          12,460         44,140,119               0.03
                                    Services, Social Networks,
                                    and Other Media Networks and
                                    Content Providers.
5171.............................  Wired and Wireless                       7,811       49,672,322           6,360         12,522,782               0.05
                                    Telecommunications (except
                                    Satellite).
5174.............................  Satellite Telecommunications.               59          491,286           8,376         14,838,437               0.06
5178.............................  All Other Telecommunications.              358        2,013,640           5,620          9,959,665               0.06
5182.............................  Computing Infrastructure                 2,409       13,757,855           5,712         11,018,831               0.05
                                    Providers, Data Processing,
                                    Web Hosting, and Related
                                    Services.
5192.............................  Web Search Portals,                        611        1,902,061           3,111          6,745,774               0.05
                                    Libraries, Archives, and
                                    Other Information Services.
5221.............................  Depository Credit                       16,260       66,680,457           4,101          5,815,480               0.07
                                    Intermediation.
5222.............................  Nondepository Credit                     6,274       23,451,028           3,738         10,353,450               0.04
                                    Intermediation.
5223.............................  Activities Related to Credit             3,968       13,782,701           3,473          5,998,640               0.06
                                    Intermediation.
5231.............................  Securities and Commodity                 3,942       12,199,622           3,095         10,423,406               0.03
                                    Contracts Intermediation and
                                    Brokerage.
5232.............................  Securities and Commodity                     4           62,437          13,904        411,532,288               0.00
                                    Exchanges.
5239.............................  Other Financial Investment              10,124       23,123,395           2,284          5,472,042               0.04
                                    Activities.
5241.............................  Insurance Carriers...........            4,350       35,116,961           8,073         74,913,679               0.01
5242.............................  Agencies, Brokerages, and               20,264       50,123,045           2,474          2,715,515               0.09
                                    Other Insurance Related
                                    Activities.
5251.............................  Insurance and Employee                     236          527,154           2,237          3,562,001               0.06
                                    Benefit Funds.
5259.............................  Other Investment Pools and                 123          255,212           2,079          2,004,745               0.10
                                    Funds.
5311.............................  Lessors of Real Estate.......           17,809       50,853,115           2,855          2,394,282               0.12
5312.............................  Offices of Real Estate Agents           16,673       36,947,635           2,216          1,136,243               0.20
                                    and Brokers.
5313.............................  Activities Related to Real              13,274       53,336,543           4,018          1,215,258               0.33
                                    Estate.
5321.............................  Automotive Equipment Rental              2,256       15,749,238           6,981          4,088,904               0.17
                                    and Leasing.
5322.............................  Consumer Goods Rental........            2,693       10,999,021           4,085          1,173,984               0.35
5323.............................  General Rental Centers.......              420        1,665,083           3,969          1,486,508               0.27
5324.............................  Commercial and Industrial                2,130       13,168,084           6,182          5,500,482               0.11
                                    Machinery and Equipment
                                    Rental and Leasing.
5331.............................  Lessors of Nonfinancial                    377        1,245,184           3,303         19,386,258               0.02
                                    Intangible Assets (except
                                    Copyrighted Works).
5411.............................  Legal Services...............           25,571       52,480,381           2,052          1,941,967               0.11
5412.............................  Accounting, Tax Preparation,            18,287       48,179,649           2,635          1,396,296               0.19
                                    Bookkeeping, and Payroll
                                    Services.
5413.............................  Architectural, Engineering,             15,623      174,866,256          11,193          3,312,024               0.34
                                    and Related Services.
5414.............................  Specialized Design Services..            4,494       13,137,406           2,923            931,984               0.31
5415.............................  Computer Systems Design and             19,606       79,048,499           4,032          3,773,095               0.11
                                    Related Services.

[[Page 70951]]

 
5416.............................  Management, Scientific, and             24,060      100,628,588           4,182          1,787,507               0.23
                                    Technical Consulting
                                    Services.
5417.............................  Scientific Research and                  2,556       33,102,069          12,948         10,398,760               0.12
                                    Development Services.
5418.............................  Advertising, Public                      5,218       30,433,443           5,833          3,373,336               0.17
                                    Relations, and Related
                                    Services.
5419.............................  Other Professional,                      9,861       64,294,316           6,520          1,535,518               0.42
                                    Scientific, and Technical
                                    Services.
5511.............................  Management of Companies and              7,687      181,889,901          23,662          2,601,094               0.91
                                    Enterprises.
5611.............................  Office Administrative                    4,694       13,289,558           2,831          2,192,216               0.13
                                    Services.
5612.............................  Facilities Support Services..              928       17,834,897          19,228          5,252,912               0.37
5613.............................  Employment Services..........            7,276      344,829,125          47,393          8,776,960               0.54
5614.............................  Business Support Services....            4,372       13,798,527           3,156          2,727,986               0.12
5615.............................  Travel Arrangement and                   3,108        6,673,364           2,147          2,592,365               0.08
                                    Reservation Services.
5616.............................  Investigation and Security               3,513       73,921,446          21,042          2,971,429               0.71
                                    Services.
5617.............................  Services to Buildings and               27,351      173,828,441           6,355            922,181               0.69
                                    Dwellings.
5619.............................  Other Support Services.......            2,751       17,358,050           6,309          2,809,043               0.22
5621.............................  Waste Collection.............            1,605        5,725,756           3,567          5,516,059               0.06
5622.............................  Waste Treatment and Disposal.              358        2,044,381           5,704          6,960,982               0.08
5629.............................  Remediation and Other Waste              1,496       10,192,723           6,814          3,165,201               0.22
                                    Management Services.
6111.............................  Elementary and Secondary                 3,291       40,472,071          12,297          4,413,940               0.28
                                    Schools.
6112.............................  Junior Colleges..............              120        1,194,543           9,970          8,501,343               0.12
6113.............................  Colleges, Universities, and                661       32,001,201          48,400         69,334,614               0.07
                                    Professional Schools.
6114.............................  Business Schools and Computer            1,248        2,668,673           2,138          1,826,775               0.12
                                    and Management Training.
6115.............................  Technical and Trade Schools..            1,228        4,444,652           3,619          1,991,961               0.18
6116.............................  Other Schools and Instruction            7,639       17,939,335           2,348            592,020               0.40
6117.............................  Educational Support Services.            1,310        3,196,265           2,439          2,241,261               0.11
6211.............................  Offices of Physicians........            9,917       25,952,877           2,617          2,598,098               0.10
6212.............................  Offices of Dentists..........            6,017       16,631,978           2,764          1,123,388               0.25
6213.............................  Offices of Other Health                  6,967       15,574,576           2,235            650,896               0.34
                                    Practitioners.
6214.............................  Outpatient Care Centers......            2,008       14,460,890           7,201          4,256,944               0.17
6215.............................  Medical and Diagnostic                     767        4,775,293           6,226          3,788,420               0.16
                                    Laboratories.
6216.............................  Home Health Care Services....            1,474       39,821,728          27,010          3,024,173               0.89
6219.............................  Other Ambulatory Health Care               507        6,057,721          11,957          4,132,554               0.29
                                    Services.
6221.............................  General Medical and Surgical               245       65,020,765         265,020        218,034,685               0.12
                                    Hospitals.
6222.............................  Psychiatric and Substance                   27        5,602,159         207,993         45,105,867               0.46
                                    Abuse Hospitals.
6223.............................  Specialty (except Psychiatric               37        3,694,704          99,601         61,909,640               0.16
                                    and Substance Abuse)
                                    Hospitals.
6231.............................  Nursing Care Facilities                    752       35,736,039          47,496          8,679,090               0.55
                                    (Skilled Nursing Facilities).
6232.............................  Residential Intellectual and             1,863       22,918,890          12,302          1,273,215               0.97
                                    Developmental Disability,
                                    Mental Health, and Substance
                                    Abuse Facilities.
6233.............................  Continuing Care Retirement               1,120       26,868,839          23,984          3,060,931               0.78
                                    Communities and Assisted
                                    Living Facilities for the
                                    Elderly.
6239.............................  Other Residential Care                     227        4,128,616          18,174          1,856,976               0.98
                                    Facilities.
6241.............................  Individual and Family                    3,329       57,309,240          17,218          1,658,588               1.04
                                    Services.
6242.............................  Community Food and Housing,                650        6,458,493           9,929          2,982,906               0.33
                                    and Emergency and Other
                                    Relief Services.
6243.............................  Vocational Rehabilitation                  328        7,785,986          23,739          2,100,542               1.13
                                    Services.
6244.............................  Child Care Services..........            3,406       61,315,616          18,003            652,479               2.76
7111.............................  Performing Arts Companies....            4,832        6,157,218           1,274          2,085,725               0.06
7112.............................  Spectator Sports.............            2,206        5,962,390           2,703         12,928,871               0.02
7113.............................  Promoters of Performing Arts,            4,362        8,735,781           2,003          4,539,819               0.04
                                    Sports, and Similar Events.
7114.............................  Agents and Managers for                  2,223        2,215,936             997          2,365,997               0.04
                                    Artists, Athletes,
                                    Entertainers, and Other
                                    Public Figures.
7115.............................  Independent Artists, Writers,           15,379       14,540,701             945            848,451               0.11
                                    and Performers.
7121.............................  Museums, Historical Sites,               4,091        7,846,087           1,918          3,102,080               0.06
                                    and Similar Institutions.
7131.............................  Amusement Parks and Arcades..            2,347       15,577,978           6,639          5,344,729               0.12
7132.............................  Gambling Industries..........            1,638        3,926,485           2,398          9,343,172               0.03
7139.............................  Other Amusement and                     39,654       70,323,368           1,773          1,310,750               0.14
                                    Recreation Industries.
7211.............................  Traveler Accommodation.......           21,598       63,177,043           2,925          5,123,987               0.06
7212.............................  RV (Recreational Vehicle)                2,754        2,698,715             980          1,029,528               0.10
                                    Parks and Recreational Camps.
7213.............................  Rooming and Boarding Houses,               746          791,148           1,061            994,545               0.11
                                    Dormitories, and Workers'
                                    Camps.
7223.............................  Special Food Services........           16,532       29,428,448           1,780          1,586,703               0.11
7224.............................  Drinking Places (Alcoholic              14,785       14,060,549             951            739,078               0.13
                                    Beverages).
7225.............................  Restaurants and Other Eating           210,896      409,134,932           1,940          1,274,637               0.15
                                    Places.
8111.............................  Automotive Repair and                   74,001      126,236,663           1,706            873,479               0.20
                                    Maintenance.
8112.............................  Electronic and Precision                 5,811       11,875,534           2,044          1,945,895               0.11
                                    Equipment Repair and
                                    Maintenance.
8113.............................  Commercial and Industrial                9,972       25,065,047           2,514          2,202,353               0.11
                                    Machinery and Equipment
                                    (except Automotive and
                                    Electronic) Repair and
                                    Maintenance.

[[Page 70952]]

 
8114.............................  Personal and Household Goods             9,830       12,454,292           1,267            559,118               0.23
                                    Repair and Maintenance.
8121.............................  Personal Care Services.......           60,820       71,616,377           1,178            360,641               0.33
8122.............................  Death Care Services..........            9,602       18,086,417           1,884          1,109,180               0.17
8123.............................  Drycleaning and Laundry                 15,411       21,745,744           1,411            916,522               0.15
                                    Services.
8129.............................  Other Personal Services......           21,448       31,265,564           1,458            691,008               0.21
8131.............................  Religious Organizations......           84,819      139,934,279           1,650            975,827               0.17
8132.............................  Grantmaking and Giving                   9,147       11,510,923           1,258          7,324,606               0.02
                                    Services.
8133.............................  Social Advocacy Organizations            8,168       11,803,888           1,445          2,343,993               0.06
8134.............................  Civic and Social                        12,043       18,907,950           1,570            859,416               0.18
                                    Organizations.
8139.............................  Business, Professional,                 26,876       37,917,962           1,411          2,057,484               0.07
                                    Labor, Political, and
                                    Similar Organizations.
9992.............................  State Government.............                8      169,386,525      20,359,760     80,797,224,446               0.03
9993.............................  Local Government.............            5,172      504,582,765          97,561         64,081,034               0.15
                                                                 ---------------------------------------------------------------------------------------
    Total........................  .............................        2,535,774    7,823,661,638           3,085          7,392,091               0.04
--------------------------------------------------------------------------------------------------------------------------------------------------------

B. Economic Feasibility Screening Analysis: Small and Very Small 
Entities
    The preceding discussion focused on the economic viability of each 
affected industry in its entirety, including entities of all sizes. 
Even though OSHA has found that the proposed standard does not threaten 
the economic viability of these industries, the agency also examines 
whether there is still a possibility that the competitive structure of 
these industries could be significantly altered. For instance, in some 
industries, if most or all small firms in that industry would have to 
close, it could reasonably be concluded that the competitive structure 
of the industry had been affected by the proposed standard.
    To address this possibility, OSHA examines the average compliance 
costs per affected small entity and very small entity for each industry 
covered under the final standard. See Section VIII.B., Profile of 
Affected Industries for a discussion of OSHA's methodology for 
estimating the number of small and very small entities.
    As with its analysis of all establishments, the agency relies on a 
screening test--costs less than one percent of revenue--to evaluate the 
impacts on small and very small entities.\91\ As with the screening 
tests for establishments of all sizes, in cases where the small and 
very small entities in particular industries are above the threshold 
level for the primary screening test, OSHA will investigate further.
---------------------------------------------------------------------------

    \91\ The agency calculates the average per-entity revenues for 
small and very small entities in each NAICS industry in the same 
manner that it calculated the average per-establishment revenues for 
its analysis of all establishments, above.
---------------------------------------------------------------------------

    OSHA notes that cost impacts for affected small or very small 
entities will generally tend to be somewhat higher, on average, than 
the cost impacts for the average business in those affected industries. 
That is to be expected. After all, smaller businesses typically suffer 
from diseconomies of scale in many aspects of their business, leading 
to lower revenue per dollar of cost and higher average costs. Small 
businesses are able to overcome these obstacles by providing 
specialized products and services, offering local service and better 
service, or otherwise creating a market niche for themselves. In a 
dynamic environment, they also tend to benefit from less institutional 
inertia. The higher cost impacts for smaller businesses estimated for 
this standard generally fall within the range observed in other OSHA 
standards, and OSHA is not aware of any record of major industry 
failures resulting from those standards.\92\ For industries that are 
below the thresholds for the cost-to-revenue test, the agency concludes 
that the costs of complying with the proposed standard are unlikely to 
threaten the survival of small entities or very small entities and are, 
consequently, unlikely to alter the competitive structure of the 
affected industries.
---------------------------------------------------------------------------

    \92\ For example, OSHA's economic analysis for the agency's 2016 
Silica rule showed cost-to-revenue ratios as high as 1.29 percent 
for small entities and 2.09 percent for very small entities (see 
OSHA's Final Economic and Regulatory Flexibility Analysis for its 
Silica rule, chapter VI, tables VI-7 and VI-8, pp. VI-87-VI-94, 
Document ID OSHA-2010-0034-4247, attachment 6).
---------------------------------------------------------------------------

    As discussed further in Section VIII.F., Initial Regulatory 
Flexibility Analysis, the agency is required by the Regulatory 
Flexibility Act to determine whether a proposed standard would likely 
have a significant economic impact on a substantial number of small 
entities. As an extension of the feasibility screening analysis, the 
agency also performed a screening analysis of costs as a percentage of 
revenues of small entities. Table VIII.D.2. and table VIII.D.3. show 
that parallel to the previous analysis of costs as percent of average 
revenues for all establishments, for all but seven (out of 298) of the 
covered NAICS industries, the cost-to-revenue ratios are generally well 
below OSHA's screening threshold of one percent, suggesting that 
compliance with this standard would be feasible for small and very 
small entities in all of these industries. Since the impact is somewhat 
higher on average to small entities, two industries, Home Health Care 
Services (NAICS 6216) and Other Residential Care Facilities (NAICS 
6239), had costs marginally above one percent, in addition to the five 
listed previously for the feasibility screening test for all 
establishments. A slightly different mix (four of 298) presents for 
Very Small Entities, the two agriculture industries listed previously 
and two of the four health care and social service industries, Other 
Residential Care Facilities (NAICS 6239) and Child Care Services (NAICS 
6244) having costs of more than one percent as a percent of revenues.
    While the impacts are marginally greater for small entities, the 
general profile does not differ significantly from the issues with 
larger entities, suggesting that the proposed standard does not pose 
unique challenges for small entities. (This result is consistent with 
the costs being overwhelmingly employee based, as opposed to 
establishment based (see Section VIII.C., Costs of Compliance)).

[[Page 70953]]

    Table VIII.D.2. shows that the estimated average cost of complying 
with the proposed standard for the average small entity in all 
industries covered by the standard is $1,946 annually, and table 
VIII.D.3. shows that the estimated average cost of the standard for the 
average very small entity is $1,178 annually.
    The tables further show that for all small entities in covered 
NAICS industries, the cost-to-revenue ratios are below OSHA's one 
percent screening threshold, except for the seven industries previously 
discussed, suggesting that compliance with this proposed standard would 
be feasible for small entities in these industries.
    As is typical with new requirements, the costs will be borne 
primarily by those businesses that have lagged in implementing safety 
measures. See Lead I, 647 F.2d at 1265 (`` `It would appear to be 
consistent with the purposes of the [OSH] Act to envisage the economic 
demise of an employer who has lagged behind the rest of the industry in 
protecting the health and safety of employees and is consequently 
financially unable to comply with new standards as quickly as other 
employers.' '') (quoting Indus. Union Dep't, AFL-CIO v. Hodgson, 499 
F.2d 467, 478 (D.C. Cir. 1974)). Indeed, one of the main 
differentiations between businesses similarly situated in the same 
industry, where one would be exempt from this proposed standard while 
the other would not, would be in situations where one employer has 
invested in air conditioning that keeps their facility below the heat 
trigger while the other has forgone those investments. The businesses 
that have already incurred many of the costs of compliance will 
presumably be at low risk of going out of business as a result of the 
standard. Even when small or very small entities in particular 
industries are above the revenue screening threshold, it would be very 
unlikely that this proposed standard would result in the alteration of 
the economic structure of these industries based on the failure of most 
or all of the small or very small entities in those industries.
    Moreover, OSHA has considered input from SBA-defined small entities 
who participated in the SBREFA process, with regard to the potential 
provisions of a regulatory framework for a heat standard. OSHA's 
adjustments to the regulatory framework presented during the panel, 
along with a set of regulatory alternatives and options drafted and 
analyzed in response to recommendations from the SBAR Panel, are also 
discussed in Section VIII.F., Initial Regulatory Flexibility Analysis.

           Table VIII.D.2--Economic Impacts on Small Entities Affected by the Proposed Standard With Costs Calculated Using a 2% Discount Rate
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                              Average
                                                                                              Total         annualized        Average      Costs as % of
                NAICS                              Industry                 Entities        annualized       cost per       revenue per       revenue
                                                                                              costs           entity          entity
--------------------------------------------------------------------------------------------------------------------------------------------------------
1111................................  Oilseed and Grain Farming........          12,511      $13,585,428          $1,086        $759,359            0.14
1112................................  Vegetable and Melon Farming......           2,127        9,980,549           4,693       1,153,664            0.41
1113................................  Fruit and Tree Nut Farming.......           6,121       14,284,547           2,334         682,745            0.34
1114................................  Greenhouse, Nursery, and                    2,720       12,359,299           4,544         741,146            0.61
                                       Floriculture Production.
1119................................  Other Crop Farming...............           9,564       15,497,239           1,620         282,465            0.57
1121................................  Cattle Ranching and Farming......          18,428       28,781,484           1,562         700,078            0.22
1122................................  Hog and Pig Farming..............           1,048        2,182,612           2,082       2,601,611            0.08
1123................................  Poultry and Egg Production.......           2,278        4,700,946           2,064       2,939,009            0.07
1124................................  Sheep and Goat Farming...........           1,548        2,393,222           1,546          88,910            1.74
1125................................  Aquaculture......................             160          616,482           3,859       1,133,734            0.34
1129................................  Other Animal Production..........           4,913        7,999,112           1,628         115,067            1.41
1131................................  Timber Tract Operations..........             442          439,946             996       1,501,147            0.07
1132................................  Forest Nurseries and Gathering of             150          152,566           1,017         790,399            0.13
                                       Forest Products.
1133................................  Logging..........................           7,980        7,648,751             958       1,563,286            0.06
1141................................  Fishing..........................           2,432        1,113,045             458         853,204            0.05
1142................................  Hunting and Trapping.............             351          374,292           1,066         799,221            0.13
1151................................  Support Activities for Crop                 4,648        5,853,520           1,259       2,707,767            0.05
                                       Production.
1152................................  Support Activities for Animal               4,640        3,376,198             728         506,802            0.14
                                       Production.
1153................................  Support Activities for Forestry..           1,658        1,398,749             844       1,111,045            0.08
2111................................  Oil and Gas Extraction...........           5,307       16,476,736           3,105      26,579,145            0.01
2131................................  Support Activities for Mining....          10,921       43,981,568           4,027       3,821,423            0.11
2211................................  Electric Power Generation,                  2,058       28,171,559          13,690      76,221,412            0.02
                                       Transmission and Distribution.
2212................................  Natural Gas Distribution.........             418        3,527,573           8,436      70,106,856            0.01
2213................................  Water, Sewage and Other Systems..           3,668        7,573,926           2,065       1,410,992            0.15
2361................................  Residential Building Construction         171,099      106,947,179             625       1,421,852            0.04
2362................................  Nonresidential Building                    40,735       62,520,995           1,535       6,719,320            0.02
                                       Construction.
2371................................  Utility System Construction......          16,774       34,191,049           2,038       3,633,655            0.06
2372................................  Land Subdivision.................           4,805        3,170,977             660       1,877,172            0.04
2373................................  Highway, Street, and Bridge                 8,285       17,087,777           2,062       6,724,608            0.03
                                       Construction.
2379................................  Other Heavy and Civil Engineering           4,056        6,569,839           1,620       3,024,764            0.05
                                       Construction.
2381................................  Foundation, Structure, and                 91,279      125,277,109           1,372       1,699,487            0.08
                                       Building Exterior Contractors.
2382................................  Building Equipment Contractors...         177,612      233,824,679           1,316       1,621,258            0.08
2383................................  Building Finishing Contractors...         114,496      106,453,318             930       1,078,107            0.09
2389................................  Other Specialty Trade Contractors          68,126       72,672,079           1,067       1,929,027            0.06
3111................................  Animal Food Manufacturing........             636        1,601,425           2,520      24,357,224            0.01
3112................................  Grain and Oilseed Milling........             250        1,211,561           4,854      62,037,403            0.01
3113................................  Sugar and Confectionery Product               868        2,204,453           2,539       9,556,299            0.03
                                       Manufacturing.
3114................................  Fruit and Vegetable Preserving                743        3,725,663           5,016      25,690,434            0.02
                                       and Specialty Food Manufacturing.
3115................................  Dairy Product Manufacturing......             588        2,637,411           4,484      49,929,979            0.01
3116................................  Animal Slaughtering and                     1,456       12,280,924           8,438      38,292,294            0.02
                                       Processing.
3117................................  Seafood Product Preparation and               221          902,567           4,087      22,008,470            0.02
                                       Packaging.
3118................................  Bakeries and Tortilla                       5,471       11,517,147           2,105       3,818,211            0.06
                                       Manufacturing.
3119................................  Other Food Manufacturing.........           1,655        5,268,917           3,183      16,374,321            0.02
3121................................  Beverage Manufacturing...........           4,226        6,542,557           1,548       8,758,819            0.02
3122................................  Tobacco Manufacturing............              58          515,881           8,848     182,294,825            0.00
3131................................  Fiber, Yarn, and Thread Mills....             102        1,037,014          10,139      19,374,286            0.05

[[Page 70954]]

 
3132................................  Fabric Mills.....................             345        1,937,288           5,609      12,945,642            0.04
3133................................  Textile and Fabric Finishing and              378        1,346,267           3,565       7,871,921            0.05
                                       Fabric Coating Mills.
3141................................  Textile Furnishings Mills........             769        2,410,151           3,134       5,547,861            0.06
3149................................  Other Textile Product Mills......           1,981        2,870,758           1,449       2,012,712            0.07
3152................................  Cut and Sew Apparel Manufacturing           1,485        1,708,817           1,151         907,132            0.13
3159................................  Apparel Accessories and Other                 279          488,329           1,750       1,772,440            0.10
                                       Apparel Manufacturing.
3161................................  Leather and Hide Tanning and                   75           78,767           1,048       6,384,614            0.02
                                       Finishing.
3162................................  Footwear Manufacturing...........             102          410,499           4,029       5,074,485            0.08
3211................................  Sawmills and Wood Preservation...           1,425        5,001,937           3,510       7,582,835            0.05
3212................................  Veneer, Plywood, and Engineered               169        1,273,144           7,533      21,682,868            0.03
                                       Wood Product Manufacturing.
3219................................  Other Wood Product Manufacturing.           4,412       11,586,726           2,626       4,072,371            0.06
3221................................  Pulp, Paper, and Paperboard Mills              35          855,082          24,193     136,863,576            0.02
3222................................  Converted Paper Product                     1,264        6,774,484           5,360      24,890,031            0.02
                                       Manufacturing.
3231................................  Printing and Related Support               12,027       11,573,349             962       2,522,782            0.04
                                       Activities.
3241................................  Petroleum and Coal Products                   464        3,199,326           6,895     177,980,216            0.00
                                       Manufacturing.
3251................................  Basic Chemical Manufacturing.....             642        4,655,288           7,251      78,530,261            0.01
3252................................  Resin, Synthetic Rubber, and                  530        4,077,855           7,695      52,682,176            0.01
                                       Artificial and Synthetic Fibers
                                       and Filaments Manufacturing.
3253................................  Pesticide, Fertilizer, and Other              355        1,140,904           3,217      18,940,264            0.02
                                       Agricultural Chemical
                                       Manufacturing.
3254................................  Pharmaceutical and Medicine                   925        5,779,821           6,251      51,766,648            0.01
                                       Manufacturing.
3255................................  Paint, Coating, and Adhesive                  705        2,479,397           3,516      16,249,794            0.02
                                       Manufacturing.
3256................................  Soap, Cleaning Compound, and                1,002        3,477,371           3,470      17,908,986            0.02
                                       Toilet Preparation Manufacturing.
3259................................  Other Chemical Product and                    872        2,542,871           2,916      12,165,378            0.02
                                       Preparation Manufacturing.
3261................................  Plastics Product Manufacturing...           4,134       19,980,060           4,833      13,921,131            0.03
3262................................  Rubber Product Manufacturing.....             699        3,192,709           4,565      12,772,546            0.04
3271................................  Clay Product and Refractory                   463        1,199,726           2,590       5,587,274            0.05
                                       Manufacturing.
3272................................  Glass and Glass Product                       706        1,989,379           2,819       6,976,531            0.04
                                       Manufacturing.
3273................................  Cement and Concrete Product                 2,173        8,394,899           3,863       8,676,117            0.04
                                       Manufacturing.
3274................................  Lime and Gypsum Product                        74          303,318           4,126      15,209,592            0.03
                                       Manufacturing.
3279................................  Other Nonmetallic Mineral Product           1,369        3,198,469           2,336       5,186,460            0.05
                                       Manufacturing.
3311................................  Iron and Steel Mills and                      191        2,633,059          13,753     115,596,140            0.01
                                       Ferroalloy Manufacturing.
3312................................  Steel Product Manufacturing from              246        1,720,852           6,991      28,374,263            0.02
                                       Purchased Steel.
3313................................  Alumina and Aluminum Production               155        1,282,335           8,290      35,439,130            0.02
                                       and Processing.
3314................................  Nonferrous Metal (except                      309        1,616,110           5,227      39,316,152            0.01
                                       Aluminum) Production and
                                       Processing.
3315................................  Foundries........................             691        2,989,596           4,329      11,281,321            0.04
3321................................  Forging and Stamping.............             991        2,784,200           2,810      10,193,180            0.03
3322................................  Cutlery and Handtool                          529          928,777           1,755       5,517,119            0.03
                                       Manufacturing.
3323................................  Architectural and Structural                5,974       16,517,707           2,765       5,735,883            0.05
                                       Metals Manufacturing.
3324................................  Boiler, Tank, and Shipping                    589        2,689,023           4,567      12,577,513            0.04
                                       Container Manufacturing.
3325................................  Hardware Manufacturing...........             272          770,518           2,836       8,866,155            0.03
3326................................  Spring and Wire Product                       492        1,152,112           2,340       6,269,990            0.04
                                       Manufacturing.
3327................................  Machine Shops; Turned Product;             11,032       15,208,419           1,379       2,901,748            0.05
                                       and Screw, Nut, and Bolt
                                       Manufacturing.
3328................................  Coating, Engraving, Heat                    2,521        5,835,961           2,315       4,178,955            0.06
                                       Treating, and Allied Activities.
3329................................  Other Fabricated Metal Product              2,806        7,766,243           2,767       7,493,462            0.04
                                       Manufacturing.
3331................................  Agriculture, Construction, and              1,247        5,944,680           4,766      18,417,556            0.03
                                       Mining Machinery Manufacturing.
3332................................  Industrial Machinery                          425        1,030,865           2,425      10,195,646            0.02
                                       Manufacturing.
3334................................  Ventilation, Heating, Air-                    699        3,921,041           5,609      15,601,508            0.04
                                       Conditioning, and Commercial
                                       Refrigeration Equipment
                                       Manufacturing.
3335................................  Metalworking Machinery                      3,010        4,202,594           1,396       4,357,322            0.03
                                       Manufacturing.
3336................................  Engine, Turbine, and Power                    337        1,582,741           4,698      25,365,617            0.02
                                       Transmission Equipment
                                       Manufacturing.
3339................................  Other General Purpose Machinery             1,762        5,979,770           3,394      12,034,903            0.03
                                       Manufacturing.
3341................................  Computer and Peripheral Equipment             415          490,089           1,182       8,911,705            0.01
                                       Manufacturing.
3342................................  Communications Equipment                      547        1,256,142           2,294      13,522,113            0.02
                                       Manufacturing.
3343................................  Audio and Video Equipment                     219          262,564           1,198       5,604,208            0.02
                                       Manufacturing.
3344................................  Semiconductor and Other                     1,680        4,552,187           2,709      13,079,398            0.02
                                       Electronic Component
                                       Manufacturing.
3345................................  Navigational, Measuring,                    2,157        4,626,878           2,145      12,820,769            0.02
                                       Electromedical, and Control
                                       Instruments Manufacturing.
3352................................  Household Appliance Manufacturing             101          332,021           3,290      14,304,913            0.02
3353................................  Electrical Equipment                          852        2,906,501           3,411      10,715,020            0.03
                                       Manufacturing.
3359................................  Other Electrical Equipment and                752        2,497,573           3,319      12,404,672            0.03
                                       Component Manufacturing.
3361................................  Motor Vehicle Manufacturing......              23           51,856           2,260      58,221,416            0.00
3362................................  Motor Vehicle Body and Trailer                803        4,874,596           6,071      15,741,094            0.04
                                       Manufacturing.
3363................................  Motor Vehicle Parts Manufacturing           1,978       13,487,337           6,817      32,394,740            0.02
3364................................  Aerospace Product and Parts                   646        3,977,519           6,160      29,941,829            0.02
                                       Manufacturing.
3365................................  Railroad Rolling Stock                         74          567,108           7,707      33,655,605            0.02
                                       Manufacturing.
3366................................  Ship and Boat Building...........             658        7,118,392          10,818      14,164,896            0.08
3369................................  Other Transportation Equipment                392          641,075           1,635       6,718,062            0.02
                                       Manufacturing.
3371................................  Household and Institutional                 4,766        9,401,064           1,972       2,859,010            0.07
                                       Furniture and Kitchen Cabinet
                                       Manufacturing.

[[Page 70955]]

 
3372................................  Office Furniture (including                 1,690        3,989,090           2,360       5,125,287            0.05
                                       Fixtures) Manufacturing.
3379................................  Other Furniture Related Product               326        1,166,170           3,581       8,591,445            0.04
                                       Manufacturing.
3391................................  Medical Equipment and Supplies              4,621        7,495,312           1,622       4,733,183            0.03
                                       Manufacturing.
3399................................  Other Miscellaneous Manufacturing           8,582       11,161,673           1,301       2,660,648            0.05
4231................................  Motor Vehicle and Motor Vehicle             1,544       11,511,623           7,456       8,053,146            0.09
                                       Parts and Supplies Merchant
                                       Wholesalers.
4232................................  Furniture and Home Furnishing               1,077        5,781,729           5,367       5,828,655            0.09
                                       Merchant Wholesalers.
4233................................  Lumber and Other Construction                 993        5,631,821           5,671       6,885,143            0.08
                                       Materials Merchant Wholesalers.
4234................................  Professional and Commercial                 2,259       10,168,859           4,501       5,929,082            0.08
                                       Equipment and Supplies Merchant
                                       Wholesalers.
4235................................  Metal and Mineral (except                     709        4,763,004           6,715      13,288,617            0.05
                                       Petroleum) Merchant Wholesalers.
4236................................  Household Appliances and                    1,907       11,364,290           5,960       8,540,329            0.07
                                       Electrical and Electronic Goods
                                       Merchant Wholesalers.
4237................................  Hardware, and Plumbing and                  1,026        5,820,745           5,674       6,361,789            0.09
                                       Heating Equipment and Supplies
                                       Merchant Wholesalers.
4238................................  Machinery, Equipment, and                   4,033       29,834,160           7,398       5,737,517            0.13
                                       Supplies Merchant Wholesalers.
4239................................  Miscellaneous Durable Goods                 2,831       10,561,663           3,731       5,222,434            0.07
                                       Merchant Wholesalers.
4241................................  Paper and Paper Product Merchant              717        3,784,639           5,277       5,821,550            0.09
                                       Wholesalers.
4242................................  Drugs and Druggists' Sundries                 662        4,340,575           6,561      10,574,055            0.06
                                       Merchant Wholesalers.
4243................................  Apparel, Piece Goods, and Notions             386        1,344,807           3,483       5,167,182            0.07
                                       Merchant Wholesalers.
4244................................  Grocery and Related Product                 2,662       15,934,090           5,986      10,630,078            0.06
                                       Merchant Wholesalers.
4245................................  Farm Product Raw Material                     325        2,641,457           8,119      23,756,996            0.03
                                       Merchant Wholesalers.
4246................................  Chemical and Allied Products                  809        4,315,458           5,336       8,980,738            0.06
                                       Merchant Wholesalers.
4247................................  Petroleum and Petroleum Products              376        3,206,820           8,522      61,864,570            0.01
                                       Merchant Wholesalers.
4248................................  Beer, Wine, and Distilled                     326        3,172,050           9,724      13,306,719            0.07
                                       Alcoholic Beverage Merchant
                                       Wholesalers.
4249................................  Miscellaneous Nondurable Goods              2,124       10,353,521           4,876       5,895,079            0.08
                                       Merchant Wholesalers.
4251................................  Wholesale Trade Agents and                  3,749        9,368,912           2,499      12,764,272            0.02
                                       Brokers.
4411................................  Automobile Dealers...............           6,500       37,276,607           5,735      15,961,277            0.04
4412................................  Other Motor Vehicle Dealers......             955        3,490,111           3,656       5,414,403            0.07
4441................................  Building Material and Supplies                544        1,021,683           1,877       2,831,193            0.07
                                       Dealers.
4451................................  Grocery and Convenience Retailers           6,886       22,913,996           3,328       3,311,379            0.10
4452................................  Specialty Food Retailers.........           1,180        2,429,585           2,059       1,053,778            0.20
4811................................  Scheduled Air Transportation.....             727       10,339,037          14,225      97,899,634            0.01
4812................................  Nonscheduled Air Transportation..           1,637        3,179,136           1,942       6,496,273            0.03
4821................................  Rail Transportation..............             113           78,448             697       1,132,927            0.06
4831................................  Deep Sea, Coastal, and Great                  606        2,154,113           3,553      16,994,169            0.02
                                       Lakes Water Transportation.
4832................................  Inland Water Transportation......             410        1,791,814           4,371       6,386,189            0.07
4841................................  General Freight Trucking.........          55,843       50,365,637             902       1,458,914            0.06
4842................................  Specialized Freight Trucking.....          39,386       41,886,506           1,063       1,812,364            0.06
4851................................  Urban Transit Systems............             513          590,618           1,151       2,151,325            0.05
4852................................  Interurban and Rural Bus                      488          896,937           1,837       2,488,321            0.07
                                       Transportation.
4853................................  Taxi and Limousine Service.......           6,453        7,243,177           1,122         862,937            0.13
4854................................  School and Employee Bus                     2,232        3,191,204           1,430       2,019,525            0.07
                                       Transportation.
4855................................  Charter Bus Industry.............             978        1,507,466           1,541       2,813,587            0.05
4859................................  Other Transit and Ground                    3,856        3,185,344             826       1,343,491            0.06
                                       Passenger Transportation.
4861................................  Pipeline Transportation of Crude               70          347,281           4,984      28,045,336            0.02
                                       Oil.
4862................................  Pipeline Transportation of                     59           90,847           1,528      15,269,599            0.01
                                       Natural Gas.
4869................................  Other Pipeline Transportation....              71          269,120           3,788      22,870,110            0.02
4871................................  Scenic and Sightseeing                        572        1,034,717           1,808       1,542,634            0.12
                                       Transportation, Land.
4872................................  Scenic and Sightseeing                      1,479        2,781,692           1,881         961,471            0.20
                                       Transportation, Water.
4879................................  Scenic and Sightseeing                        229          354,470           1,551       1,442,518            0.11
                                       Transportation, Other.
4881................................  Support Activities for Air                  3,639        7,427,615           2,041       2,726,627            0.07
                                       Transportation.
4882................................  Support Activities for Rail                   494        1,414,555           2,861       3,694,856            0.08
                                       Transportation.
4883................................  Support Activities for Water                1,852        6,207,901           3,353       4,619,864            0.07
                                       Transportation.
4884................................  Support Activities for Road                 9,012        6,993,625             776       1,019,225            0.08
                                       Transportation.
4885................................  Freight Transportation                     12,925       18,974,056           1,468       2,467,206            0.06
                                       Arrangement.
4889................................  Other Support Activities for                1,387        1,669,460           1,203       1,765,588            0.07
                                       Transportation.
4921................................  Couriers and Express Delivery               3,724       12,926,412           3,471       9,170,589            0.04
                                       Services.
4922................................  Local Messengers and Local                  3,431        3,012,249             878       1,312,866            0.07
                                       Delivery.
4931................................  Warehousing and Storage..........           9,681       56,004,514           5,785       3,692,460            0.16
5121................................  Motion Picture and Video                    2,568        7,638,794           2,975       1,544,741            0.19
                                       Industries.
5122................................  Sound Recording Industries.......             466          946,190           2,032       1,914,032            0.11
5174................................  Satellite Telecommunications.....              46          165,892           3,602       3,473,723            0.10
5182................................  Computing Infrastructure                    1,352        3,731,170           2,759       2,821,642            0.10
                                       Providers, Data Processing, Web
                                       Hosting, and Related Services.
5221................................  Depository Credit Intermediation.           1,562       21,857,409          13,995      15,334,364            0.09
5222................................  Nondepository Credit                        1,085        3,521,500           3,245       2,825,317            0.11
                                       Intermediation.
5223................................  Activities Related to Credit                1,822        4,068,120           2,232       1,274,881            0.18
                                       Intermediation.
5232................................  Securities and Commodity                        1           26,178          39,745     753,808,884            0.01
                                       Exchanges.
5239................................  Other Financial Investment                  1,542        3,322,810           2,154       3,014,962            0.07
                                       Activities.
5241................................  Insurance Carriers...............             724        7,767,572          10,729      64,751,762            0.02
5242................................  Agencies, Brokerages, and Other            18,002       37,871,610           2,104         884,543            0.24
                                       Insurance Related Activities.

[[Page 70956]]

 
5251................................  Insurance and Employee Benefit                161          187,816           1,164         860,458            0.14
                                       Funds.
5259................................  Other Investment Pools and Funds.             122          253,899           2,075       1,915,830            0.11
5311................................  Lessors of Real Estate...........          13,445       32,370,835           2,408       1,498,519            0.16
5312................................  Offices of Real Estate Agents and          14,553       27,775,521           1,909         848,299            0.22
                                       Brokers.
5313................................  Activities Related to Real Estate          10,787       33,316,314           3,088         865,500            0.36
5321................................  Automotive Equipment Rental and               567        2,987,344           5,267       2,647,455            0.20
                                       Leasing.
5322................................  Consumer Goods Rental............           1,185        5,301,598           4,475       1,093,599            0.41
5323................................  General Rental Centers...........             318        1,344,257           4,222       1,436,198            0.29
5324................................  Commercial and Industrial                   1,171        5,466,318           4,667       3,114,198            0.15
                                       Machinery and Equipment Rental
                                       and Leasing.
5331................................  Lessors of Nonfinancial                       315          671,532           2,130       3,900,891            0.05
                                       Intangible Assets (except
                                       Copyrighted Works).
5411................................  Legal Services...................          23,897       49,298,948           2,063       1,105,731            0.19
5412................................  Accounting, Tax Preparation,               15,652       36,586,403           2,338         715,353            0.33
                                       Bookkeeping, and Payroll
                                       Services.
5413................................  Architectural, Engineering, and            12,833       75,874,312           5,913       1,482,804            0.40
                                       Related Services.
5414................................  Specialized Design Services......           4,402       11,949,232           2,715         783,080            0.35
5415................................  Computer Systems Design and                16,220       39,798,676           2,454       1,363,070            0.18
                                       Related Services.
5416................................  Management, Scientific, and                22,491       62,683,511           2,787         917,797            0.30
                                       Technical Consulting Services.
5417................................  Scientific Research and                     2,115       15,224,604           7,199       5,734,418            0.13
                                       Development Services.
5418................................  Advertising, Public Relations,              4,587       16,632,694           3,626       1,610,062            0.23
                                       and Related Services.
5419................................  Other Professional, Scientific,             8,774       45,327,608           5,166       1,037,261            0.50
                                       and Technical Services.
5511................................  Management of Companies and                   932        7,466,268           8,009       7,794,296            0.10
                                       Enterprises.
5611................................  Office Administrative Services...           4,204       10,143,593           2,413       1,807,749            0.13
5612................................  Facilities Support Services......             296        3,898,123          13,148       4,474,249            0.29
5613................................  Employment Services..............           3,752       42,559,048          11,344       2,963,924            0.38
5614................................  Business Support Services........           3,342        5,943,802           1,778       1,306,752            0.14
5615................................  Travel Arrangement and                      1,972        3,129,421           1,587       1,663,607            0.10
                                       Reservation Services.
5616................................  Investigation and Security                  2,773       25,002,454           9,018       1,245,244            0.72
                                       Services.
5617................................  Services to Buildings and                  26,019      112,901,810           4,339         671,194            0.65
                                       Dwellings.
5619................................  Other Support Services...........           2,399        7,136,600           2,975       1,533,830            0.19
5621................................  Waste Collection.................           1,078        2,523,921           2,342       3,245,312            0.07
5622................................  Waste Treatment and Disposal.....             181          743,227           4,112       3,879,488            0.11
5629................................  Remediation and Other Waste                 1,259        6,361,525           5,055       2,114,365            0.24
                                       Management Services.
6111................................  Elementary and Secondary Schools.           2,856       34,194,636          11,975       4,338,191            0.28
6112................................  Junior Colleges..................              61          567,155           9,272       7,096,235            0.13
6113................................  Colleges, Universities, and                   178          641,408           3,603       3,148,365            0.11
                                       Professional Schools.
6114................................  Business Schools and Computer and           1,150        2,051,773           1,785       1,184,543            0.15
                                       Management Training.
6115................................  Technical and Trade Schools......           1,020        3,125,752           3,063       1,475,233            0.21
6116................................  Other Schools and Instruction....           7,124       15,777,099           2,215         471,098            0.47
6117................................  Educational Support Services.....           1,184        2,055,225           1,736         994,278            0.17
6211................................  Offices of Physicians............           7,538       16,396,965           2,175       1,557,548            0.14
6212................................  Offices of Dentists..............           5,517       15,448,753           2,800       1,107,348            0.25
6213................................  Offices of Other Health                     5,985       13,236,859           2,212         610,067            0.36
                                       Practitioners.
6214................................  Outpatient Care Centers..........             799        6,631,683           8,303       3,531,393            0.24
6215................................  Medical and Diagnostic                        326        1,639,918           5,023       2,880,366            0.17
                                       Laboratories.
6216................................  Home Health Care Services........           1,021       21,196,909          20,756       1,947,504            1.07
6219................................  Other Ambulatory Health Care                  290        2,399,519           8,280       2,122,696            0.39
                                       Services.
6221................................  General Medical and Surgical                   58        3,146,213          54,588      31,988,544            0.17
                                       Hospitals.
6222................................  Psychiatric and Substance Abuse                10        1,136,474         118,967      26,840,059            0.44
                                       Hospitals.
6223................................  Specialty (except Psychiatric and               6          408,435          64,547      24,345,151            0.27
                                       Substance Abuse) Hospitals.
6231................................  Nursing Care Facilities (Skilled              377       15,692,040          41,623       7,737,051            0.54
                                       Nursing Facilities).
6232................................  Residential Intellectual and                  454       12,424,041          27,345       2,746,969            1.00
                                       Developmental Disability, Mental
                                       Health, and Substance Abuse
                                       Facilities.
6233................................  Continuing Care Retirement                    779       13,425,442          17,232       2,104,725            0.82
                                       Communities and Assisted Living
                                       Facilities for the Elderly.
6239................................  Other Residential Care Facilities             136        3,155,732          23,216       2,165,006            1.07
6241................................  Individual and Family Services...           2,496       39,826,256          15,956       1,571,030            1.02
6242................................  Community Food and Housing, and               480        5,254,947          10,949       2,633,784            0.42
                                       Emergency and Other Relief
                                       Services.
6243................................  Vocational Rehabilitation                     172        4,469,310          25,964       2,335,393            1.11
                                       Services.
6244................................  Child Care Services..............           2,687       51,565,482          19,189         676,561            2.84
7111................................  Performing Arts Companies........           4,679        5,483,031           1,172       1,560,279            0.08
7112................................  Spectator Sports.................           2,011        2,409,683           1,198       2,328,568            0.05
7113................................  Promoters of Performing Arts,               4,046        5,398,753           1,334       2,099,056            0.06
                                       Sports, and Similar Events.
7114................................  Agents and Managers for Artists,            2,119        2,111,109             996       1,445,877            0.07
                                       Athletes, Entertainers, and
                                       Other Public Figures.
7115................................  Independent Artists, Writers, and          15,342       14,460,165             942         835,413            0.11
                                       Performers.
7121................................  Museums, Historical Sites, and              3,845        6,836,964           1,778       2,394,793            0.07
                                       Similar Institutions.
7131................................  Amusement Parks and Arcades......           1,742        3,288,557           1,888       1,040,189            0.18
7132................................  Gambling Industries..............           1,000        2,273,300           2,272       5,012,918            0.05
7139................................  Other Amusement and Recreation             34,659       51,264,046           1,479       1,051,729            0.14
                                       Industries.
7211................................  Traveler Accommodation...........          17,375       32,853,003           1,891       2,184,689            0.09
7212................................  RV (Recreational Vehicle) Parks             2,543        2,405,045             946         991,813            0.10
                                       and Recreational Camps.

[[Page 70957]]

 
7213................................  Rooming and Boarding Houses,                  687          741,076           1,079         930,215            0.12
                                       Dormitories, and Workers' Camps.
7223................................  Special Food Services............           7,295        8,312,585           1,139         857,031            0.13
7224................................  Drinking Places (Alcoholic                 14,383       13,061,680             908         663,521            0.14
                                       Beverages).
7225................................  Restaurants and Other Eating              157,253      276,972,590           1,761       1,144,923            0.15
                                       Places.
8111................................  Automotive Repair and Maintenance          62,789      100,273,474           1,597         798,630            0.20
8113................................  Commercial and Industrial                   8,982       14,997,313           1,670       1,261,858            0.13
                                       Machinery and Equipment (except
                                       Automotive and Electronic)
                                       Repair and Maintenance.
8114................................  Personal and Household Goods                9,417       11,449,589           1,216         455,661            0.27
                                       Repair and Maintenance.
8121................................  Personal Care Services...........          52,932       64,529,881           1,219         346,123            0.35
8122................................  Death Care Services..............           6,955       13,214,986           1,900       1,130,650            0.17
8123................................  Drycleaning and Laundry Services.          13,051       16,733,433           1,282         564,862            0.23
8129................................  Other Personal Services..........          16,792       22,209,398           1,323         509,230            0.26
8131................................  Religious Organizations..........          83,837      126,171,312           1,505         722,894            0.21
8132................................  Grantmaking and Giving Services..           7,839        8,889,289           1,134       3,473,007            0.03
8133................................  Social Advocacy Organizations....           6,903        8,993,435           1,303       1,442,084            0.09
8134................................  Civic and Social Organizations...          11,030       15,706,906           1,424         697,379            0.20
8139................................  Business, Professional, Labor,             25,710       33,664,444           1,309       1,384,987            0.09
                                       Political, and Similar
                                       Organizations.
9993................................  Local Government.................           4,846      132,114,558          27,261      17,292,921            0.16
                                                                        --------------------------------------------------------------------------------
    Total...........................  .................................       1,985,235    3,863,384,856           1,946       2,403,819            0.08
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source: OSHA estimate.


        Table VIII.D.3--Economic Impacts on Very Small Entities Affected by the Proposed Standard With Costs Calculated Using a 2% Discount Rate
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                              Average
                                                                                              Total         annualized        Average      Costs as % of
                NAICS                              Industry                 Entities        annualized       cost per       revenue per       revenue
                                                                                              costs           entity          entity
--------------------------------------------------------------------------------------------------------------------------------------------------------
1111................................  Oilseed and Grain Farming........           7,184       $6,027,437            $839        $609,184            0.14
1112................................  Vegetable and Melon Farming......           1,227        3,233,900           2,636         705,291            0.37
1113................................  Fruit and Tree Nut Farming.......           3,060        4,119,361           1,346         384,931            0.35
1114................................  Greenhouse, Nursery, and                    1,545        4,149,308           2,686         513,448            0.52
                                       Floriculture Production.
1119................................  Other Crop Farming...............           5,537        6,434,964           1,162         198,860            0.58
1121................................  Cattle Ranching and Farming......          10,474       11,742,592           1,121         523,461            0.21
1122................................  Hog and Pig Farming..............             585          921,175           1,575       2,022,974            0.08
1123................................  Poultry and Egg Production.......           1,356        2,018,022           1,488       2,264,037            0.07
1124................................  Sheep and Goat Farming...........             856          968,612           1,131          59,994            1.89
1125................................  Aquaculture......................              91          239,911           2,630         875,290            0.30
1129................................  Other Animal Production..........           2,806        3,272,814           1,166          88,841            1.31
1131................................  Timber Tract Operations..........             429          403,940             942       1,293,445            0.07
1132................................  Forest Nurseries and Gathering of             144          104,419             725         679,386            0.11
                                       Forest Products.
1133................................  Logging..........................           7,530        6,292,246             836       1,170,494            0.07
1141................................  Fishing..........................           2,416        1,100,212             455         667,346            0.07
1142................................  Hunting and Trapping.............             331          292,626             885         619,029            0.14
1151................................  Support Activities for Crop                 4,102        3,213,003             783       1,530,220            0.05
                                       Production.
1152................................  Support Activities for Animal               4,531        2,962,939             654         405,439            0.16
                                       Production.
1153................................  Support Activities for Forestry..           1,534        1,037,673             676         765,904            0.09
2111................................  Oil and Gas Extraction...........           4,571        6,341,178           1,387       2,574,156            0.05
2131................................  Support Activities for Mining....           8,845       14,462,495           1,635         937,066            0.17
2211................................  Electric Power Generation,                    832        2,254,730           2,709      13,316,386            0.02
                                       Transmission and Distribution.
2212................................  Natural Gas Distribution.........             267          546,792           2,049      10,690,728            0.02
2213................................  Water, Sewage and Other Systems..           3,468        5,937,995           1,712         850,747            0.20
2361................................  Residential Building Construction         167,394       90,561,837             541       1,043,976            0.05
2362................................  Nonresidential Building                    34,810       32,498,908             934       2,948,013            0.03
                                       Construction.
2371................................  Utility System Construction......          13,929       14,564,718           1,046       1,657,874            0.06
2372................................  Land Subdivision.................           4,615        2,626,758             569       1,167,179            0.05
2373................................  Highway, Street, and Bridge                 6,251        5,486,633             878       2,619,746            0.03
                                       Construction.
2379................................  Other Heavy and Civil Engineering           3,581        3,418,173             954       1,444,677            0.07
                                       Construction.
2381................................  Foundation, Structure, and                 83,470       72,226,262             865         936,942            0.09
                                       Building Exterior Contractors.
2382................................  Building Equipment Contractors...         161,684      141,354,524             874         847,521            0.10
2383................................  Building Finishing Contractors...         108,028       74,449,281             689         653,438            0.11
2389................................  Other Specialty Trade Contractors          62,342       43,480,559             697       1,039,609            0.07
3111................................  Animal Food Manufacturing........             377          349,776             928       5,316,620            0.02
3112................................  Grain and Oilseed Milling........             130          273,983           2,115      22,940,721            0.01
3113................................  Sugar and Confectionery Product               652          541,708             831       1,163,232            0.07
                                       Manufacturing.
3114................................  Fruit and Vegetable Preserving                441          532,718           1,207       3,760,308            0.03
                                       and Specialty Food Manufacturing.
3115................................  Dairy Product Manufacturing......             337          456,581           1,353       9,285,097            0.01
3116................................  Animal Slaughtering and                       996          872,620             876       2,401,951            0.04
                                       Processing.
3117................................  Seafood Product Preparation and               129          107,828             838       3,136,053            0.03
                                       Packaging.
3118................................  Bakeries and Tortilla                       4,379        4,017,779             918         635,675            0.14
                                       Manufacturing.

[[Page 70958]]

 
3119................................  Other Food Manufacturing.........           1,111        1,075,034             968       2,724,529            0.04
3121................................  Beverage Manufacturing...........           3,429        2,263,370             660       1,398,536            0.05
3122................................  Tobacco Manufacturing............              32           42,411           1,311       6,587,893            0.02
3131................................  Fiber, Yarn, and Thread Mills....              60           75,096           1,254       2,191,371            0.06
3132................................  Fabric Mills.....................             192          233,984           1,217       3,435,732            0.04
3133................................  Textile and Fabric Finishing and              263          271,517           1,031       1,915,018            0.05
                                       Fabric Coating Mills.
3141................................  Textile Furnishings Mills........             630          573,335             910         780,741            0.12
3149................................  Other Textile Product Mills......           1,705        1,270,778             745         614,109            0.12
3151................................  Apparel Knitting Mills...........              54           66,320           1,228       1,443,320            0.09
3152................................  Cut and Sew Apparel Manufacturing           2,095        1,429,596             682         637,842            0.11
3159................................  Apparel Accessories and Other                 236          188,102             796         619,537            0.13
                                       Apparel Manufacturing.
3161................................  Leather and Hide Tanning and                   61           42,671             698       2,839,687            0.02
                                       Finishing.
3162................................  Footwear Manufacturing...........              75          123,351           1,655       2,193,374            0.08
3169................................  Other Leather and Allied Product              302          187,558             621         626,299            0.10
                                       Manufacturing.
3211................................  Sawmills and Wood Preservation...           1,006        1,185,132           1,179       1,727,380            0.07
3212................................  Veneer, Plywood, and Engineered               264          633,617           2,400       4,044,768            0.06
                                       Wood Product Manufacturing.
3219................................  Other Wood Product Manufacturing.           3,327        3,257,167             979       1,053,722            0.09
3221................................  Pulp, Paper, and Paperboard Mills              27          376,078          13,794      93,208,301            0.01
3222................................  Converted Paper Product                       559          893,086           1,597       4,579,693            0.03
                                       Manufacturing.
3231................................  Printing and Related Support               10,124        5,790,603             572         693,094            0.08
                                       Activities.
3241................................  Petroleum and Coal Products                   244          494,702           2,027      28,484,143            0.01
                                       Manufacturing.
3251................................  Basic Chemical Manufacturing.....             277          556,651           2,011      21,892,698            0.01
3252................................  Resin, Synthetic Rubber, and                  226          335,765           1,485       6,835,167            0.02
                                       Artificial and Synthetic Fibers
                                       and Filaments Manufacturing.
3253................................  Pesticide, Fertilizer, and Other              229          350,781           1,534       7,269,726            0.02
                                       Agricultural Chemical
                                       Manufacturing.
3254................................  Pharmaceutical and Medicine                   546          603,519           1,106       3,960,913            0.03
                                       Manufacturing.
3255................................  Paint, Coating, and Adhesive                  448          542,317           1,211       3,140,147            0.04
                                       Manufacturing.
3256................................  Soap, Cleaning Compound, and                  704          655,288             931       2,390,628            0.04
                                       Toilet Preparation Manufacturing.
3259................................  Other Chemical Product and                    579          723,101           1,250       3,072,599            0.04
                                       Preparation Manufacturing.
3261................................  Plastics Product Manufacturing...           2,192        2,911,100           1,328       2,782,966            0.05
3262................................  Rubber Product Manufacturing.....             382          557,177           1,459       2,487,702            0.06
3271................................  Clay Product and Refractory                   328          323,850             989       1,473,179            0.07
                                       Manufacturing.
3272................................  Glass and Glass Product                       539          546,405           1,014       1,791,588            0.06
                                       Manufacturing.
3273................................  Cement and Concrete Product                 1,336        1,655,935           1,240       2,456,404            0.05
                                       Manufacturing.
3274................................  Lime and Gypsum Product                        51          122,726           2,409       7,351,270            0.03
                                       Manufacturing.
3279................................  Other Nonmetallic Mineral Product           1,006        1,149,905           1,143       1,653,776            0.07
                                       Manufacturing.
3311................................  Iron and Steel Mills and                      103          218,406           2,121       6,567,240            0.03
                                       Ferroalloy Manufacturing.
3312................................  Steel Product Manufacturing from              121          265,350           2,191       7,339,261            0.03
                                       Purchased Steel.
3313................................  Alumina and Aluminum Production                82          262,328           3,197      12,497,676            0.03
                                       and Processing.
3314................................  Nonferrous Metal (except                      178          278,430           1,566       8,757,990            0.02
                                       Aluminum) Production and
                                       Processing.
3315................................  Foundries........................             391          547,296           1,398       2,192,210            0.06
3321................................  Forging and Stamping.............             556          557,664           1,003       2,020,339            0.05
3322................................  Cutlery and Handtool                          373          259,248             695       1,107,327            0.06
                                       Manufacturing.
3323................................  Architectural and Structural                4,125        4,085,887             991       1,456,833            0.07
                                       Metals Manufacturing.
3324................................  Boiler, Tank, and Shipping                    300          423,339           1,409       3,917,337            0.04
                                       Container Manufacturing.
3325................................  Hardware Manufacturing...........             186          153,954             828       1,511,537            0.05
3326................................  Spring and Wire Product                       298          292,858             983       1,589,842            0.06
                                       Manufacturing.
3327................................  Machine Shops; Turned Product;              8,812        6,785,989             770         910,823            0.08
                                       and Screw, Nut, and Bolt
                                       Manufacturing.
3328................................  Coating, Engraving, Heat                    1,740        1,753,611           1,008         985,271            0.10
                                       Treating, and Allied Activities.
3329................................  Other Fabricated Metal Product              1,998        2,026,136           1,014       1,910,855            0.05
                                       Manufacturing.
3331................................  Agriculture, Construction, and                776          880,986           1,135       2,303,225            0.05
                                       Mining Machinery Manufacturing.
3332................................  Industrial Machinery                          951          827,287             870       1,790,885            0.05
                                       Manufacturing.
3333................................  Commercial and Service Industry               602          467,902             777       1,741,883            0.04
                                       Machinery Manufacturing.
3334................................  Ventilation, Heating, Air-                    409          485,787           1,186       2,390,594            0.05
                                       Conditioning, and Commercial
                                       Refrigeration Equipment
                                       Manufacturing.
3335................................  Metalworking Machinery                      2,174        1,503,816             692       1,172,111            0.06
                                       Manufacturing.
3336................................  Engine, Turbine, and Power                    186          279,911           1,504       4,514,698            0.03
                                       Transmission Equipment
                                       Manufacturing.
3339................................  Other General Purpose Machinery             1,576        1,782,884           1,131       2,828,012            0.04
                                       Manufacturing.
3341................................  Computer and Peripheral Equipment             317          181,009             570       2,040,422            0.03
                                       Manufacturing.
3342................................  Communications Equipment                      374          275,245             735       2,213,015            0.03
                                       Manufacturing.
3343................................  Audio and Video Equipment                     180           98,831             548       1,509,740            0.04
                                       Manufacturing.
3344................................  Semiconductor and Other                       991          740,401             747       1,810,399            0.04
                                       Electronic Component
                                       Manufacturing.
3345................................  Navigational, Measuring,                    1,411          961,637             682       2,280,952            0.03
                                       Electromedical, and Control
                                       Instruments Manufacturing.
3346................................  Manufacturing and Reproducing                 158           80,247             509         869,333            0.06
                                       Magnetic and Optical Media.
3351................................  Electric Lighting Equipment                   321          290,904             906       2,228,223            0.04
                                       Manufacturing.
3352................................  Household Appliance Manufacturing              73           67,216             915       1,907,392            0.05

[[Page 70959]]

 
3353................................  Electrical Equipment                          543          585,477           1,078       2,265,967            0.05
                                       Manufacturing.
3359................................  Other Electrical Equipment and                530          775,438           1,462       4,923,782            0.03
                                       Component Manufacturing.
3361................................  Motor Vehicle Manufacturing......              72           42,019             586       8,079,095            0.01
3362................................  Motor Vehicle Body and Trailer                462          571,401           1,237       2,128,388            0.06
                                       Manufacturing.
3363................................  Motor Vehicle Parts Manufacturing           1,140        1,248,555           1,096       2,450,442            0.04
3364................................  Aerospace Product and Parts                   368          569,759           1,550       4,750,992            0.03
                                       Manufacturing.
3365................................  Railroad Rolling Stock                         32          104,712           3,303      12,137,746            0.03
                                       Manufacturing.
3366................................  Ship and Boat Building...........             446          605,519           1,357       1,347,324            0.10
3369................................  Other Transportation Equipment                321          258,348             804       1,487,253            0.05
                                       Manufacturing.
3371................................  Household and Institutional                 4,244        3,437,887             810         718,130            0.11
                                       Furniture and Kitchen Cabinet
                                       Manufacturing.
3372................................  Office Furniture (including                 1,162        1,046,524             901       1,149,394            0.08
                                       Fixtures) Manufacturing.
3379................................  Other Furniture Related Product               216          288,388           1,337       2,340,433            0.06
                                       Manufacturing.
3391................................  Medical Equipment and Supplies              3,950        2,735,349             693         758,887            0.09
                                       Manufacturing.
3399................................  Other Miscellaneous Manufacturing           7,399        5,215,239             705         801,390            0.09
4231................................  Motor Vehicle and Motor Vehicle             1,257        4,993,354           3,973       3,303,747            0.12
                                       Parts and Supplies Merchant
                                       Wholesalers.
4232................................  Furniture and Home Furnishing                 910        3,110,498           3,417       2,854,446            0.12
                                       Merchant Wholesalers.
4233................................  Lumber and Other Construction                 785        2,505,110           3,193       3,557,039            0.09
                                       Materials Merchant Wholesalers.
4234................................  Professional and Commercial                 1,916        5,577,568           2,912       2,405,983            0.12
                                       Equipment and Supplies Merchant
                                       Wholesalers.
4235................................  Metal and Mineral (except                     556        2,106,984           3,790       6,228,340            0.06
                                       Petroleum) Merchant Wholesalers.
4236................................  Household Appliances and                    1,576        5,580,492           3,542       3,369,434            0.11
                                       Electrical and Electronic Goods
                                       Merchant Wholesalers.
4237................................  Hardware, and Plumbing and                    816        2,636,524           3,230       2,796,763            0.12
                                       Heating Equipment and Supplies
                                       Merchant Wholesalers.
4238................................  Machinery, Equipment, and                   3,312       15,267,247           4,610       2,896,468            0.16
                                       Supplies Merchant Wholesalers.
4239................................  Miscellaneous Durable Goods                 2,551        6,358,104           2,492       2,832,277            0.09
                                       Merchant Wholesalers.
4241................................  Paper and Paper Product Merchant              610        2,004,758           3,287       2,995,604            0.11
                                       Wholesalers.
4242................................  Drugs and Druggists' Sundries                 563        1,888,913           3,356       4,020,123            0.08
                                       Merchant Wholesalers.
4243................................  Apparel, Piece Goods, and Notions           1,248        3,098,845           2,483       2,808,295            0.09
                                       Merchant Wholesalers.
4244................................  Grocery and Related Product                 2,242        7,359,247           3,283       4,893,717            0.07
                                       Merchant Wholesalers.
4245................................  Farm Product Raw Material                     266        1,240,969           4,671      11,316,686            0.04
                                       Merchant Wholesalers.
4246................................  Chemical and Allied Products                  676        2,375,082           3,516       5,030,093            0.07
                                       Merchant Wholesalers.
4247................................  Petroleum and Petroleum Products              263        1,242,062           4,718      20,772,751            0.02
                                       Merchant Wholesalers.
4248................................  Beer, Wine, and Distilled                     243          763,626           3,147       3,176,806            0.10
                                       Alcoholic Beverage Merchant
                                       Wholesalers.
4249................................  Miscellaneous Nondurable Goods              1,870        6,010,140           3,215       2,900,974            0.11
                                       Merchant Wholesalers.
4251................................  Wholesale Trade Agents and                  3,577        7,395,194           2,068       8,758,811            0.02
                                       Brokers.
4411................................  Automobile Dealers...............           4,702        9,420,631           2,004       3,255,236            0.06
4412................................  Other Motor Vehicle Dealers......           1,853        4,518,777           2,439       2,697,277            0.09
4413................................  Automotive Parts, Accessories,              4,859       11,159,040           2,297       1,134,410            0.20
                                       and Tire Retailers.
4441................................  Building Material and Supplies              5,693        7,059,545           1,240       1,614,974            0.08
                                       Dealers.
4442................................  Lawn and Garden Equipment and               2,502        5,016,485           2,005       1,498,082            0.13
                                       Supplies Retailers.
4451................................  Grocery and Convenience Retailers          10,521       16,794,972           1,596       1,054,320            0.15
4452................................  Specialty Food Retailers.........           3,551        5,729,397           1,613         900,891            0.18
4453................................  Beer, Wine, and Liquor Retailers.           5,163        5,975,343           1,157       1,325,671            0.09
4491................................  Furniture and Home Furnishings              6,010        8,962,736           1,491       1,223,523            0.12
                                       Retailers.
4492................................  Electronics and Appliance                   3,217        4,908,069           1,525       1,030,417            0.15
                                       Retailers.
4551................................  Department Stores................             148          190,770           1,287       1,621,586            0.08
4552................................  Warehouse Clubs, Supercenters,              2,556        3,419,681           1,338         842,471            0.16
                                       and Other General Merchandise
                                       Retailers.
4561................................  Health and Personal Care                    7,776        9,533,570           1,226       1,791,759            0.07
                                       Retailers.
4571................................  Gasoline Stations................          10,327       15,498,593           1,501       2,804,858            0.05
4572................................  Fuel Dealers.....................             649        1,060,755           1,635       2,693,189            0.06
4581................................  Clothing and Clothing Accessories           5,967        8,712,135           1,460         698,207            0.21
                                       Retailers.
4582................................  Shoe Retailers...................           1,010        1,421,801           1,408       1,020,151            0.14
4583................................  Jewelry, Luggage, and Leather               2,976        3,898,966           1,310       1,079,268            0.12
                                       Goods Retailers.
4591................................  Sporting Goods, Hobby, and                  5,150        7,074,290           1,374         864,136            0.16
                                       Musical Instrument Retailers.
4592................................  Book Retailers and News Dealers..             774          988,633           1,278         744,295            0.17
4593................................  Florists.........................           2,213        3,540,277           1,600         494,498            0.32
4594................................  Office Supplies, Stationery, and            3,317        4,621,207           1,393         627,443            0.22
                                       Gift Retailers.
4595................................  Used Merchandise Retailers.......           2,352        3,240,613           1,378         608,402            0.23
4599................................  Other Miscellaneous Retailers....           5,911        8,732,908           1,477       1,042,423            0.14
4811................................  Scheduled Air Transportation.....             278          293,355           1,054       3,080,504            0.03
4812................................  Nonscheduled Air Transportation..           1,285        1,286,819           1,001       2,040,509            0.05
4821................................  Rail Transportation..............              96           51,361             536         399,619            0.13
4831................................  Deep Sea, Coastal, and Great                  455          544,184           1,196       2,200,414            0.05
                                       Lakes Water Transportation.
4832................................  Inland Water Transportation......             323          453,643           1,403       1,350,810            0.10
4841................................  General Freight Trucking.........          51,643       37,499,799             726         861,013            0.08
4842................................  Specialized Freight Trucking.....          35,020       26,650,522             761         892,912            0.09
4851................................  Urban Transit Systems............             373          312,637             839         839,880            0.10
4852................................  Interurban and Rural Bus                      332          422,567           1,274         833,268            0.15
                                       Transportation.

[[Page 70960]]

 
4853................................  Taxi and Limousine Service.......           5,931        6,596,898           1,112         473,725            0.23
4854................................  School and Employee Bus                     1,444        1,578,496           1,093         381,438            0.29
                                       Transportation.
4855................................  Charter Bus Industry.............             663          764,143           1,152         976,121            0.12
4859................................  Other Transit and Ground                    3,097        2,381,262             769         514,988            0.15
                                       Passenger Transportation.
4861................................  Pipeline Transportation of Crude               27           34,499           1,282       5,687,521            0.02
                                       Oil.
4862................................  Pipeline Transportation of                     59           90,847           1,528      15,269,599            0.01
                                       Natural Gas.
4869................................  Other Pipeline Transportation....              29           37,586           1,288       4,867,763            0.03
4871................................  Scenic and Sightseeing                        474          570,363           1,203         670,486            0.18
                                       Transportation, Land.
4872................................  Scenic and Sightseeing                      1,385        2,109,958           1,524         589,761            0.26
                                       Transportation, Water.
4879................................  Scenic and Sightseeing                        208          272,900           1,311         812,572            0.16
                                       Transportation, Other.
4881................................  Support Activities for Air                  2,961        3,481,748           1,176       1,058,641            0.11
                                       Transportation.
4882................................  Support Activities for Rail                   315          430,553           1,366       1,603,240            0.09
                                       Transportation.
4883................................  Support Activities for Water                1,396        1,914,888           1,372       1,256,551            0.11
                                       Transportation.
4884................................  Support Activities for Road                 8,222        6,121,945             745         687,092            0.11
                                       Transportation.
4885................................  Freight Transportation                     11,283       15,674,157           1,389       1,583,872            0.09
                                       Arrangement.
4889................................  Other Support Activities for                1,202        1,095,829             912         799,155            0.11
                                       Transportation.
4921................................  Couriers and Express Delivery               3,125        2,811,195             900         843,986            0.11
                                       Services.
4922................................  Local Messengers and Local                  2,990        2,455,403             821         741,162            0.11
                                       Delivery.
4931................................  Warehousing and Storage..........           3,555        3,599,514           1,012       1,301,304            0.08
5121................................  Motion Picture and Video                    2,383        4,673,631           1,962         903,851            0.22
                                       Industries.
5122................................  Sound Recording Industries.......             445          780,716           1,754         660,025            0.27
5131................................  Newspaper, Periodical, Book, and            1,936        4,503,697           2,326         816,692            0.28
                                       Directory Publishers.
5132................................  Software Publishers..............           1,057        2,023,518           1,915       1,268,517            0.15
5161................................  Radio and Television Broadcasting             370        1,470,235           3,969         662,207            0.60
                                       Stations.
5162................................  Media Streaming Distribution                  235          560,991           2,388       1,346,479            0.18
                                       Services, Social Networks, and
                                       Other Media Networks and Content
                                       Providers.
5171................................  Wired and Wireless                            942        1,900,994           2,018       1,249,302            0.16
                                       Telecommunications (except
                                       Satellite).
5174................................  Satellite Telecommunications.....              40           86,847           2,157       1,745,466            0.12
5178................................  All Other Telecommunications.....             287          502,736           1,753       1,126,736            0.16
5182................................  Computing Infrastructure                    1,112        2,196,650           1,976       1,171,961            0.17
                                       Providers, Data Processing, Web
                                       Hosting, and Related Services.
5192................................  Web Search Portals, Libraries,                468          867,704           1,853         507,510            0.37
                                       Archives, and Other Information
                                       Services.
5221................................  Depository Credit Intermediation.             637        1,709,643           2,682       1,711,700            0.16
5222................................  Nondepository Credit                        1,654        3,919,691           2,369       1,191,143            0.20
                                       Intermediation.
5223................................  Activities Related to Credit                1,718        3,212,716           1,870         758,941            0.25
                                       Intermediation.
5231................................  Securities and Commodity                    1,349        2,298,865           1,704       1,235,568            0.14
                                       Contracts Intermediation and
                                       Brokerage.
5232................................  Securities and Commodity                        0           19,633          39,745     753,808,884            0.01
                                       Exchanges.
5239................................  Other Financial Investment                  6,852       11,878,438           1,734       1,247,480            0.14
                                       Activities.
5241................................  Insurance Carriers...............             499        1,011,256           2,025       3,600,269            0.06
5242................................  Agencies, Brokerages, and Other            17,366       34,184,872           1,968         575,155            0.34
                                       Insurance Related Activities.
5251................................  Insurance and Employee Benefit                197          166,858             849         198,788            0.43
                                       Funds.
5259................................  Other Investment Pools and Funds.             112          200,679           1,786       1,085,641            0.16
5311................................  Lessors of Real Estate...........          12,961       26,616,095           2,054       1,090,656            0.19
5312................................  Offices of Real Estate Agents and          14,379       25,261,103           1,757         700,221            0.25
                                       Brokers.
5313................................  Activities Related to Real Estate          10,077       22,407,861           2,224         584,901            0.38
5321................................  Automotive Equipment Rental and               482        1,447,641           3,004       1,018,247            0.29
                                       Leasing.
5322................................  Consumer Goods Rental............           1,039        3,003,692           2,891         609,218            0.47
5323................................  General Rental Centers...........             284          865,973           3,049         969,539            0.31
5324................................  Commercial and Industrial                     949        2,282,588           2,404       1,447,107            0.17
                                       Machinery and Equipment Rental
                                       and Leasing.
5331................................  Lessors of Nonfinancial                       285          476,238           1,669       3,054,162            0.05
                                       Intangible Assets (except
                                       Copyrighted Works).
5411................................  Legal Services...................          22,852       45,807,442           2,005         747,237            0.27
5412................................  Accounting, Tax Preparation,               14,754       29,735,652           2,015         425,212            0.47
                                       Bookkeeping, and Payroll
                                       Services.
5413................................  Architectural, Engineering, and            11,568       42,680,149           3,690         796,165            0.46
                                       Related Services.
5414................................  Specialized Design Services......           4,322       10,844,535           2,509         651,156            0.39
5415................................  Computer Systems Design and                15,074       30,869,789           2,048         699,158            0.29
                                       Related Services.
5416................................  Management, Scientific, and                21,484       48,439,074           2,255         605,529            0.37
                                       Technical Consulting Services.
5417................................  Scientific Research and                     1,662        4,503,806           2,709       1,184,901            0.23
                                       Development Services.
5418................................  Advertising, Public Relations,              4,240       11,597,282           2,735         972,915            0.28
                                       and Related Services.
5419................................  Other Professional, Scientific,             8,042       31,055,715           3,862         718,191            0.54
                                       and Technical Services.
5511................................  Management of Companies and                   622        1,694,619           2,724       2,000,475            0.14
                                       Enterprises.
5611................................  Office Administrative Services...           3,518        5,423,804           1,542         785,494            0.20
5612................................  Facilities Support Services......             157          441,128           2,817       1,344,810            0.21
5613................................  Employment Services..............           2,522        4,435,122           1,758         862,254            0.20
5614................................  Business Support Services........           2,939        3,932,901           1,338         637,724            0.21
5615................................  Travel Arrangement and                      1,846        2,452,247           1,328       1,145,290            0.12
                                       Reservation Services.
5616................................  Investigation and Security                  2,305        7,402,537           3,212         568,222            0.57
                                       Services.
5617................................  Services to Buildings and                  24,202       62,022,534           2,563         441,221            0.58
                                       Dwellings.
5619................................  Other Support Services...........           2,194        4,403,819           2,007         960,942            0.21
5621................................  Waste Collection.................             893        1,162,660           1,301       1,262,504            0.10
5622................................  Waste Treatment and Disposal.....             140          316,092           2,251       1,725,940            0.13

[[Page 70961]]

 
5629................................  Remediation and Other Waste                 1,086        3,133,580           2,885       1,098,195            0.26
                                       Management Services.
6111................................  Elementary and Secondary Schools.           1,169        3,475,761           2,973         637,302            0.47
6112................................  Junior Colleges..................              29          111,992           3,817       2,336,262            0.16
6113................................  Colleges, Universities, and                   119          231,971           1,952       1,512,355            0.13
                                       Professional Schools.
6114................................  Business Schools and Computer and           1,062        1,591,435           1,498         755,854            0.20
                                       Management Training.
6115................................  Technical and Trade Schools......             841        1,646,426           1,959         687,422            0.28
6116................................  Other Schools and Instruction....           6,476       11,488,813           1,774         332,175            0.53
6117................................  Educational Support Services.....           1,096        1,574,151           1,437         604,768            0.24
6211................................  Offices of Physicians............           6,908       12,269,746           1,776         960,870            0.18
6212................................  Offices of Dentists..............           5,290       13,513,854           2,555         948,924            0.27
6213................................  Offices of Other Health                     5,695       10,110,019           1,775         447,256            0.40
                                       Practitioners.
6214................................  Outpatient Care Centers..........             536        1,544,461           2,879         989,325            0.29
6215................................  Medical and Diagnostic                        265          717,035           2,703       1,182,302            0.23
                                       Laboratories.
6216................................  Home Health Care Services........             653        2,917,046           4,468         518,702            0.86
6219................................  Other Ambulatory Health Care                  209          655,184           3,137         797,038            0.39
                                       Services.
6221................................  General Medical and Surgical                    4           20,164           5,297      10,704,238            0.05
                                       Hospitals.
6222................................  Psychiatric and Substance Abuse                 1           60,072          40,967      15,140,669            0.27
                                       Hospitals.
6223................................  Specialty (except Psychiatric and               2           89,129          45,058      23,112,360            0.19
                                       Substance Abuse) Hospitals.
6231................................  Nursing Care Facilities (Skilled               97          299,181           3,092       1,138,055            0.27
                                       Nursing Facilities).
6232................................  Residential Intellectual and                  246        1,184,615           4,820         495,389            0.97
                                       Developmental Disability, Mental
                                       Health, and Substance Abuse
                                       Facilities.
6233................................  Continuing Care Retirement                    523        2,224,552           4,252         439,078            0.97
                                       Communities and Assisted Living
                                       Facilities for the Elderly.
6239................................  Other Residential Care Facilities              83          513,007           6,216         469,247            1.32
6241................................  Individual and Family Services...           1,805        7,386,994           4,092         424,361            0.96
6242................................  Community Food and Housing, and               334        1,555,480           4,659         990,632            0.47
                                       Emergency and Other Relief
                                       Services.
6243................................  Vocational Rehabilitation                      81          345,131           4,262         566,673            0.75
                                       Services.
6244................................  Child Care Services..............           2,132       20,144,880           9,448         290,434            3.25
7111................................  Performing Arts Companies........           4,171        4,129,821             990         787,860            0.13
7112................................  Spectator Sports.................           1,794        1,430,879             797       1,258,295            0.06
7113................................  Promoters of Performing Arts,               3,604        3,665,186           1,017       1,122,492            0.09
                                       Sports, and Similar Events.
7114................................  Agents and Managers for Artists,            2,047        2,033,576             993       1,093,566            0.09
                                       Athletes, Entertainers, and
                                       Other Public Figures.
7115................................  Independent Artists, Writers, and          15,202       14,251,524             937         787,943            0.12
                                       Performers.
7121................................  Museums, Historical Sites, and              3,149        3,311,160           1,051         608,424            0.17
                                       Similar Institutions.
7131................................  Amusement Parks and Arcades......           1,354        1,316,414             972         516,918            0.19
7132................................  Gambling Industries..............             744          922,020           1,239       1,354,532            0.09
7139................................  Other Amusement and Recreation             28,297       22,821,999             807         483,584            0.17
                                       Industries.
7211................................  Traveler Accommodation...........          12,993       15,574,139           1,199         877,297            0.14
7212................................  RV (Recreational Vehicle) Parks             2,293        1,620,981             707         721,900            0.10
                                       and Recreational Camps.
7213................................  Rooming and Boarding Houses,                  654          651,616             996         650,782            0.15
                                       Dormitories, and Workers' Camps.
7223................................  Special Food Services............           6,293        4,826,527             767         453,753            0.17
7224................................  Drinking Places (Alcoholic                 12,801        9,231,321             721         450,393            0.16
                                       Beverages).
7225................................  Restaurants and Other Eating              117,267      109,738,307             936         537,890            0.17
                                       Places.
8111................................  Automotive Repair and Maintenance          64,015       85,582,777           1,337         646,006            0.21
8112................................  Electronic and Precision                    4,843        7,081,340           1,462         555,490            0.26
                                       Equipment Repair and Maintenance.
8113................................  Commercial and Industrial                   8,375       11,158,572           1,332         842,857            0.16
                                       Machinery and Equipment (except
                                       Automotive and Electronic)
                                       Repair and Maintenance.
8114................................  Personal and Household Goods                9,205       10,159,719           1,104         380,439            0.29
                                       Repair and Maintenance.
8121................................  Personal Care Services...........          50,363       59,103,771           1,174         267,441            0.44
8122................................  Death Care Services..............           6,418        9,445,610           1,472         854,725            0.17
8123................................  Drycleaning and Laundry Services.          12,190       12,520,561           1,027         353,835            0.29
8129................................  Other Personal Services..........          15,818       15,920,372           1,006         339,338            0.30
8131................................  Religious Organizations..........          76,718       98,017,873           1,278         417,227            0.31
8132................................  Grantmaking and Giving Services..           7,573        8,483,782           1,120       2,705,446            0.04
8133................................  Social Advocacy Organizations....           6,199        6,958,994           1,123         816,788            0.14
8134................................  Civic and Social Organizations...          10,249       12,512,391           1,221         479,271            0.25
8139................................  Business, Professional, Labor,             23,841       28,061,383           1,177         819,457            0.14
                                       Political, and Similar
                                       Organizations.
9993................................  Local Government.................           1,922        4,052,837           2,109       1,111,959            0.19
                                                                        --------------------------------------------------------------------------------
    Total...........................  .................................       1,847,745    2,177,399,776           1,178         987,455            0.12
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source: OSHA estimate.


[[Page 70962]]

E. Benefits

I. Introduction
    OSHA's proposed standard for Heat Injury and Illness Prevention in 
Outdoor and Indoor Work Settings is a crucial step towards ensuring the 
health, safety, and well-being of employees with occupational exposure 
to hazardous heat. Compliance with this standard is projected to yield 
substantial health and safety benefits, primarily through the reduction 
of occupational non-fatal heat-related injuries and illnesses (HRIs) 
and heat-related fatalities. These include severe conditions such as 
heat stroke, which can be fatal if not promptly treated, and heat 
exhaustion, which can lead to more serious complications if ignored. To 
estimate the health and safety benefits of this standard, OSHA has 
conducted an analysis of data on workplace incidents involving exposure 
to heat. In this section, OSHA will first present the available BLS 
data on HRIs and heat-related fatalities. After that, there is a 
discussion of underreporting issues surrounding these data which leads 
to a presentation of OSHA's underreporting adjusted count of HRIs and 
heat-related fatalities. Even with this adjustment, there remains a 
great deal of uncertainty surrounding the extent of underreporting, 
other parameters used in this estimation of health and safety benefits, 
as well as additional potential benefits, all of which the agency 
discusses next in an uncertainty analysis. Finally, this section 
includes a sensitivity analysis that calculates the potential benefits 
of this standard assuming different parameters to demonstrate the range 
of potential quantifiable benefits.
II. Fatal and Non-Fatal Heat-Related Injuries and Illnesses
    OSHA estimated the potential benefits of the proposed standard by 
determining the number of HRIs and heat-related fatalities that could 
be prevented through its provisions. This estimation was based on data 
regarding occupational fatalities and HRIs resulting from exposure to 
environmental heat. OSHA conducted this analysis using data from the 
BLS Injuries, Illnesses, and Fatalities (IIF) program. The IIF program 
collects data annually through two major surveys: the Census of Fatal 
Occupational Injuries (CFOI) and the Survey of Occupational Injuries 
and Illnesses (SOII). OSHA identified the number of heat-related 
fatalities and HRIs by searching BLS' CFOI and SOII databases for 
incidents captured under BLS event or exposure classification code 
531--Exposure to Environmental Heat.
A. Heat-Related Fatalities
    The CFOI, a Federal/State cooperative program, aims to provide 
accurate, comprehensive, and timely information on occupational 
fatalities. According to the CFOI data, between 1992 and 2022, there 
were 1,042 fatal cases due to employee exposure to environmental heat 
(BLS, 2024c). As depicted in table VIII.E.1., while the annual number 
of heat-related fatalities has fluctuated over this 31-year period, a 
gradual increasing trend in the annual average is evident.

Table VIII.E.1--Occupational Fatalities: Exposure to Environmental Heat,
                          All Ownerships, U.S.
                               [1992-2022]
------------------------------------------------------------------------
                                                             Number of
                          Year                              fatalities
------------------------------------------------------------------------
1992....................................................              12
1993....................................................              22
1994....................................................              28
1995....................................................              35
1996....................................................              18
1997....................................................              22
1998....................................................              34
1999....................................................              35
2000....................................................              21
2001....................................................              24
2002....................................................              40
2003....................................................              29
2004....................................................              18
2005....................................................              47
2006....................................................              44
2007....................................................              32
2008....................................................              27
2009....................................................              35
2010....................................................              40
2011....................................................              61
2012....................................................              31
2013....................................................              34
2014....................................................              18
2015....................................................              37
2016....................................................              39
2017....................................................              32
2018....................................................              49
2019....................................................              43
2020....................................................              56
2021....................................................              36
2022....................................................              43
                                                         ---------------
    Total Fatalities....................................           1,042
------------------------------------------------------------------------
Source: BLS, 2024c.

    To assess recent trends, OSHA focused its analysis on heat-related 
fatalities between 2011 and 2022. Over this 12-year timeframe, BLS CFOI 
data reported a total of 479 work-related fatalities from exposure to 
environmental heat, an average of 40 fatalities per year. OSHA also 
evaluated the fatality counts by industry. Due to BLS publication 
guidelines, some industry-level estimates were not publishable, denoted 
by dashes in the BLS tables. OSHA used the BLS data to estimate the 
number of fatalities by industry for those cases. OSHA used four steps 
to estimate the number of industry fatalities in years with undisclosed 
BLS data.
    First, OSHA reviewed the total annual number of heat-related 
fatalities in all industries, comparing this total to the sum of annual 
total fatalities in private industry and government. In all cases where 
the sum of the fatalities in the two categories did not match the total 
annual fatalities, one of the categories had an undisclosed annual 
fatality count. Therefore, OSHA assumed that the fatality count for the 
undisclosed estimate was equal to the difference between total annual 
fatalities and the fatalities in the published estimate (total for 
private industry or government). For example, in 2020, the total number 
of fatalities in all industries was 56, the total number of fatalities 
in private industry was 52, and the total in government was 
undisclosed. OSHA estimated that the number of heat-related fatalities 
in government was equal to the difference, four.
    Second, OSHA reviewed the total heat-related deaths in all private 
industry and compared to the sum of heat-related fatalities in private 
goods-producing industries and private service-producing industries 
combined. Since these two groups cover all private industry, the 
numbers are expected to be equal. In 2019-2022, the data for both 
categories (goods-producing and service-providing) was undisclosed. 
OSHA estimated the number of fatalities for both categories for 2019-
2022. Using the data from 2011-2018, OSHA divided the average 
percentage of heat-related private industry fatalities that were 
attributable to each group, estimating that 63 percent of private 
industry fatalities were in goods-producing industries and the 
remaining 37 percent were in service-producing industries. In each of 
the four years with undisclosed data, OSHA estimated the total 
fatalities in goods-producing and service-providing industries by 
multiplying each percentage by the total number of private industry 
annual heat-related fatalities. For example, in 2019, OSHA estimates 
that 63 percent of the private industry fatalities, 25.3 fatalities, 
are in goods-producing industries.
    Next, OSHA reviewed the super-sectors within private goods-
producing and private service-providing industries, comparing the total 
annual fatalities in each category to the sum of the annual fatalities 
of the lower, more

[[Page 70963]]

detailed underlying super-sectors.\93\ In years where the comparison 
showed a mismatch due to undisclosed data, OSHA estimated the data for 
the undisclosed super-sectors by distributing the difference between 
the total annual fatalities and the sum of fatalities in the underlying 
super-sectors across the super-sectors with undisclosed data. More 
specifically, the estimate for these undisclosed super-sectors was set 
equal to the difference described above multiplied by the percentage of 
non-fatal heat-related incidents \94\ by super-sector. This percentage 
is calculated by the estimate of average annual heat-related non-fatal 
injuries and illnesses within the super-sector divided by the average 
total number of heat-related incidents in the category in which it 
belongs (i.e., goods-producing or service-providing).
---------------------------------------------------------------------------

    \93\ The underlying super-sectors of Goods-Producing Industries 
are Natural Resources and Mining (includes agriculture), 
Construction, and Manufacturing. The underlying super-sectors within 
Service-Providing industries are Trade, Transportation, and 
Utilities; Information; Financial Activities; Professional and 
Business Services; Education and Health Services; Leisure and 
Hospitality; and Other Services.
    \94\ The percentage of total domain-level non-fatal heat-related 
incidents by super-sector was calculated using the SOII data from 
2011-2022, described in more detail in section VIII.E.II.B., below.
---------------------------------------------------------------------------

    Finally, OSHA examined the annual fatality counts for government 
and used a different method to estimate fatalities due to the 
differences in scope between SOII and CFOI.\95\ For each year, OSHA 
calculated the difference between the total annual heat-related 
fatalities in government and the sum of annual fatality counts by all 
government ownership types (Federal, State, and local). OSHA assumed 
this difference represents the number of fatalities for ownership types 
with undisclosed yearly estimates. OSHA evenly distributed the 
difference across all government ownerships with undisclosed estimates 
for that year. For example, in 2020 there were four total heat-related 
fatalities in all government. Since none of the government ownership 
types had disclosed estimates, OSHA estimated that local, State, and 
Federal Government had 1.3 (4/3) fatalities each. Table VIII.E.2. 
presents the total estimated fatality counts for 2011 to 2022 by 
industry groups.
---------------------------------------------------------------------------

    \95\ SOII excludes Federal Government ownership and CFOI does 
not.
---------------------------------------------------------------------------

    Further analysis of the data revealed that an estimated 88.1 
percent or 422 of these fatalities occurred within private industry, 
while 11.9 percent or 57 fatalities were recorded in Federal, State, 
and local governments. Within the private industry, the Goods Producing 
industries accounted for 262 of these estimated fatalities, with 
Construction accounting for 162 of the incidents within that sector. 
Natural Resources and Mining (which includes agriculture) and 
Manufacturing accounted for 52 and 49 of the estimated fatalities 
within the Goods-Producing industries respectively. Additionally, 160 
of the 422 fatalities in private industry occurred in the Service-
Providing industries, which includes super-sectors such as Trade, 
Transportation and Utilities, Leisure and Hospitality, and Professional 
and Business Services. Professional and Business Services (this NAICS 
super-sector can include disparate occupations, including janitors, 
material movers, groundskeeping workers, office clerks, security 
guards, architects, accountants, engineers, general managers, waste 
collectors, and lawyers) made up nearly 45 percent of all fatalities 
within the Service Providing industries, accounting for 71 of the 160 
fatalities within this group. These findings are detailed below in 
table VIII.E.2., illustrating the distribution of fatalities across 
different sectors and industries.

 Table VIII.E.2--Estimated Occupational Fatalities by Industry: Exposure
     to Environmental Heat, Number and Percent, All Ownerships, U.S.
                               [2011-2022]
------------------------------------------------------------------------
                                 Estimated total      Percent of total
          Industry            number of fatalities       fatalities
------------------------------------------------------------------------
Total Injuries Fatalities...                   479  ....................
Private Industry \a\........                   422                  88.1
Goods Producing Industries                     262                  54.8
 \b\ \c\....................
Natural Resources and Mining                    52                  10.8
Construction................                   162                  33.7
Manufacturing...............                    49                  10.3
Service Providing Industries                   160                  33.3
 \b\ \c\....................
Trade, Transportation and                       45                   9.4
 Utilities..................
Information.................                     7                   1.4
Financial Activities........                     5                   1.0
Professional and Business                       71                  14.8
 Services...................
Education and Health                             7                   1.4
 Services...................
Leisure and Hospitality.....                    15                   3.2
Other Services..............                    10                   2.0
Government \a\ \d\..........                    57                  11.9
    Federal Government......                    26                   5.5
    State Government........                    10                   2.1
    Local Government........                    21                   4.3
------------------------------------------------------------------------
Source: OSHA derived estimates based on BLS, 2024c.
 \a\ OSHA estimated years with undisclosed data using the difference
  between total annual fatalities and the sum of private industry and
  government fatalities.
 \b\ OSHA estimated years with undisclosed estimates for goods-producing
  industry totals and service-providing industry totals by comparing the
  annual sum of both categories to the total annual private industry
  fatalities and adjusting for the average percentage of private
  industries that fall within each category.
 \c\ For years with undisclosed data in the underlying super-sectors
  within these categories, OSHA estimated the number of fatalities by
  multiplying the number of fatalities unaccounted for in the published
  data by a ratio of the non-fatal heat-related injuries and illnesses
  for the super-sector.

[[Page 70964]]

 
 \d\ Estimates for the three different government ownership codes with
  annual undisclosed data were estimated by distributing the residual
  between the total annual government fatalities and the sum of
  published fatalities at the more detailed government ownership level,
  evenly across all government ownership types with undisclosed
  estimates.

B. Non-Fatal Heat-Related Injuries and Illnesses (HRIs)
    The BLS SOII is a Federal/State cooperative program that publishes 
estimates on non-fatal occupational injuries and illnesses, including 
HRIs. From 2011 to 2022, SOII recorded a total of 39,450 HRIs that 
required days away from work, averaging 3,288 HRIs per year (BLS, 
2023b; BLS, 2023g; and BLS, 2023h). As detailed in table VIII.E.3., 
35.8 percent of these HRIs required only one day away from work to 
recover after the incident, 21.5 percent required two days, and 23.9 
percent needed three to five days. The remaining 18.8 percent of cases 
needed six or more days away from work for recovery from injuries and 
illnesses caused by exposure to environmental heat.

 Table VIII.E.3--Non-Fatal Occupational Injuries and Illnesses Requiring
Days Away From Work: Exposure to Environmental Heat, Number and Percent,
                          All Ownerships, U.S.
                               [2011-2022]
------------------------------------------------------------------------
                               Number of non-fatal  Percent of total non-
                                  injuries and       fatal injuries and
                                    illnesses             illnesses
------------------------------------------------------------------------
Total Non-Fatal Injuries and                39,450  ....................
 Illnesses..................
Number of days away from
 work:
    Cases involving 1 day...                14,130                  35.8
    Cases involving 2 days..                 8,500                  21.5
    Cases involving 3-5 days                 9,440                  23.9
    Cases involving 6-10                     3,660                   9.3
     days...................
    Cases involving 11-20                    1,760                   4.5
     days...................
    Cases involving 21-30                      480                   1.2
     days...................
    Cases involving 31 or                    1,500                   3.8
     more days..............
Median days away from work                       2  ....................
 \a\........................
------------------------------------------------------------------------
Source: OSHA calculations based on BLS, 2023b; BLS, 2023g; and BLS,
  2023h.
Note: Because of rounding and data exclusion of nonclassifiable
  responses, data may not sum to the totals. Days away from work include
  those that result in days away from work with or without job transfer
  or restriction.
\a\ Median days away from work is the measure used to summarize the
  varying lengths of absences from work among the cases with days away
  from work. Half the cases involved more days and half involved less
  days than a specified median. Median days away from work are
  represented in actual values.

    Table VIII.E.4. details the BLS' SOII estimates of annual incidence 
rates of HRIs between 2011 and 2022. Over this period, the average 
estimated annual incidence rate is 3 cases per 100,000 full-time 
workers for HRIs. This incidence rate indicates the annual frequency of 
injuries and illnesses due to heat exposure.

 Table VIII.E.4--Non-Fatal Occupational Injuries or Illnesses: Exposure
  to Environmental Heat, Number and Annual Incidence Rates per 100,000
                      Workers, All Ownerships, U.S.
                               [2011-2022]
------------------------------------------------------------------------
                               Number of non-fatal   Incidence rate per
            Year                   injuries or        100,000 full-time
                                    illnesses              workers
------------------------------------------------------------------------
2011........................                 4,420                     4
2012........................                 4,170                     4
2013........................                 3,160                     3
2014........................                 2,660                     2
2015........................                 2,830                     3
2016........................                 4,110                     4
2017........................                 3,180                     3
2018........................                 3,950                     3
2019........................                 3,080                     3
2020........................                 2,330                     2
2021 & 2022.................                 5,560                     2
                             -------------------------------------------
    Total Non-Fatal Injuries                39,450  ....................
     and Illnesses, All
     Ownerships.............
    Average Non-Fatal                        3,288                     3
     Injuries and Illnesses
     Per Year...............
------------------------------------------------------------------------
Source: BLS, 2023b; BLS, 2023g; and BLS, 2023h.
Note: Starting with 2021, BLS published data biennially. The number of
  HRIs reported for 2021 and 2022, is a biennial estimate.

    Table VIII.E.5. presents the number of HRIs by industry from 2011 
to 2022. Similar to the findings illustrated in table VIII.E.2., table 
VIII.E.5. demonstrates that the majority of HRIs also occur 
predominantly within private industry, accounting for 79.9 percent or 
31,510 of the 39,450 non-fatal injuries and illnesses. Twenty-one 
percent of HRIs occurred within State and local governments, accounting 
for 7,930 of all HRIs. Within private industry, more

[[Page 70965]]

than half of all recorded HRIs occurred in the Service Providing 
sector, which accounted for 18,460 of the total 31,510 HRIs recorded. 
The Trade, Transportation, and Utilities industry (which includes 
Wholesale Trade, Retail Trade, Transportation and Warehousing, and 
Utilities) made up 8,010 of HRIs within the Service Providing sector, 
followed by Professional and Business Services, and Leisure and 
Hospitality with 4,260, and 1,790 HRIs, respectively. The Goods 
Producing sector accounted for 13,050 of the total HRIs within private 
industry, most of which occurred within the Construction and 
Manufacturing industries, with 6,130 and 5,100 non-fatal cases 
respectively.

    Table VIII.E.5--Non-Fatal Occupational Injuries and Illnesses by
    Industry: Exposure to Environmental Heat, Number and Percent, All
                            Ownerships, U.S.
                               [2011-2022]
------------------------------------------------------------------------
                                                      Percent of total
          Industry             Number of injuries       injuries and
                                  and illnesses           illnesses
------------------------------------------------------------------------
Total Injuries and Illnesses                39,450  ....................
------------------------------------------------------------------------
Private Industry............                31,510                  79.9
------------------------------------------------------------------------
Goods Producing Industries..                13,050                  33.1
------------------------------------------------------------------------
Natural Resources and Mining                 1,790                   4.5
Agriculture, Forestry,                       1,200                   3.0
 Fishing and Hunting........
Mining......................                   580                   1.5
Construction................                 6,130                  15.5
Manufacturing...............                 5,100                  12.9
------------------------------------------------------------------------
Service Providing Industries                18,460                  46.8
------------------------------------------------------------------------
Trade, Transportation and                    8,010                  20.3
 Utilities..................
Wholesale Trade.............                 1,570                   4.0
Retail Trade................                 2,200                   5.6
Transportation and                           3,900                   9.9
 Warehousing................
Utilities...................                   330                   0.8
Information.................                 1,140                   2.9
Financial Activities........                   810                   2.1
Finance and Insurance.......  ....................  ....................
Real Estate and Rental and                     680                   1.7
 Leasing....................
Professional and Business                    4,260                  10.8
 Services...................
Professional, Scientific,                      120                   0.3
 and Technical Services.....
Management of Companies and                     60                   0.2
 Enterprises................
Administrative and support                   3,520                   8.9
 and waste management and
 remediation services.......
Education and Health                         1,140                   2.9
 Services...................
Educational Services........                   110                   0.3
Healthcare and Social                        1,000                   2.5
 Assistance.................
Leisure and Hospitality.....                 1,790                   4.5
Arts, Entertainment, and                       540                   1.4
 Recreation.................
Accommodation and Food                       1,230                   3.1
 Services...................
Other Services..............                 1,250                   3.2
Other Services, Except                       1,250                   3.2
 Public Administration......
Public Administration.......  ....................  ....................
------------------------------------------------------------------------
State Government............                 1,490                   3.8
Local Government............                 6,440                  16.3
------------------------------------------------------------------------
Source: OSHA calculation from BLS, 2023b; BLS, 2023g; and BLS, 2023h.
Note: Because of rounding and data exclusion for detailed categories
  that did not meet the BLS publication guidelines, data may not sum to
  the totals. The SOII excludes all work-related fatalities as well as
  non-fatal work injuries and illnesses to the self-employed, to workers
  on farms with 10 or fewer employees, to private household workers; to
  volunteers, and to Federal Government workers.

C. Underreporting
    Based on an analysis of relevant academic literature (discussed in 
detail in Section V.A., Risk Assessment), OSHA has determined that 
heat-related occupational fatalities and HRIs are underreported due to 
(1) employers not being fully compliant with recordkeeping rules, (2) 
employees not reporting cases to their employers, (3) a lack of 
identifying heat as the cause of a heat-related injury or illness, and 
(4) the scope and inclusion criteria of the various surveillance data.
I. Underreporting of Heat-Related Fatalities
    BLS CFOI is well-regarded as the most complete and authoritative 
source on fatal workplace injuries and estimates of its magnitude of 
underreporting of occupational fatalities do not exist. However, there 
may be factors specific to heat-related fatalities that make CFOI 
particularly likely to misclassify the cause of death as being due to 
some other cause. This could mean that heat-related fatalities may be 
historically excluded from CFOI (e.g., cause of death is listed as 
cardiac arrest) or listed under another, not heat-specific Occupational 
Injury and Illness Classification System (OIICS) category (e.g., a 
worker faints due to heat exposure, falls from a height, and 
subsequently suffers a fatal traumatic injury). Additionally, as

[[Page 70966]]

discussed in Section V.A., Risk Assessment, the documentation upon 
which BLS relies to code occupational fatalities (e.g., death 
certificates, coroner reports) may have limitations for heat-related 
fatalities due to the lack of expertise or experience of the individual 
determining the cause of death and whether the individual witnessed the 
events preceding the fatality. Therefore, OSHA has preliminarily 
determined that there is reason to believe that the number of heat-
related fatalities in CFOI are undercounted, but precise estimates of 
this quantification do not exist.
II. OSHA's Underreporting Adjustment--Heat-Related Fatalities
    Heat-related fatalities are often identified in public health 
surveillance through review of International Classification of Diseases 
(ICD) codes listed in death certificates, which are known to be limited 
in their capture of heat as a cause-of-death (Shen et al., 1998). 
However, epidemiologists have increasingly used statistical techniques 
to identify excess deaths attributable to heat, both globally and in 
the United States, regardless of the cause-of-death listed on the death 
certificate. A recent study from 2020 estimated that, on average, 5,608 
excess deaths were the result of heat each year between 1997 and 2006 
in the 297 counties examined (representing approximately 62 percent of 
the U.S. population) or 9,045 excess deaths per year when extrapolated 
to the full nation (Weinberger et al., 2020). Estimates for similar 
time periods using the death certificate approach ranged from 618 to 
658 heat-related deaths per year across the U.S. (Xu, 2012; Fowler et 
al., 2013). This would suggest that nationally heat-related deaths may 
be 13.7-to-14.6 fold undercounted. However, it is unclear if this ratio 
could be applied to CFOI estimates of occupational heat-related 
fatalities, as it is not clear what proportion of these excess deaths 
occurred among workers. Recent evidence from Mexico indicates that 
heat-related excess deaths are concentrated among working-age 
individuals and children (preprint by Wilson et al., 2024). If the same 
pattern holds in the U.S., then the undercounting estimates above 
(13.7-14.6) might be understating the magnitude of the undercount for 
workers. However, another recent study that examined heat-related 
excess deaths in Europe found that these deaths were predominantly 
concentrated among individuals over the age of 65 (Ballester et al., 
2023). If this pattern were true for the U.S., the undercounting 
estimates above might be overstating the magnitude of undercounting for 
workers. These two studies had important differences in methodology 
(e.g., use of exposure metric, use of observational weather data, and 
age groups analyzed) and underlying population (e.g., age 
distribution), and the researchers were not able to characterize work-
related deaths. Given that the proportion of work-related deaths among 
the total estimated excess heat-related deaths in the U.S. is unknown, 
OSHA did not adjust the ratio derived from comparing Weinberger et 
al.'s estimates to Xu and Fowler et al.'s counts. Therefore, for this 
analysis, OSHA estimates that occupational fatalities due to heat are 
undercounted by a factor of 14. Additional values of the undercount--
both higher and lower--are presented later in this section in a 
sensitivity analysis. OSHA welcomes comment on the estimates of avoided 
fatalities, the underreporting adjustment, data sources, and 
methodologies employed here. The agency welcomes additional studies 
that OSHA should consider and comment on whether there are more 
appropriate underreporting factors that should be used to adjust 
reported fatalities in the final economic analysis.
III. Underreporting of Non-Fatal HRIs
    As discussed in Section V.A., Risk Assessment, researchers and 
government agencies have long acknowledged the shortcomings of BLS's 
SOII in accurately estimating all non-fatal occupational injuries and 
illnesses. One limitation is the scope of cases for which BLS has 
historically reported enough information to identify HRIs--only those 
cases involving days away from work.\96\ Another limitation of SOII is 
the reliance on employer-reported data, as research has demonstrated 
that employers are not always fully compliant with recordkeeping rules. 
Quantifying the magnitude of the undercounting of SOII is difficult, 
but comparisons to workers' compensation and other databases provide 
some context for the potential magnitude of undercounting.
---------------------------------------------------------------------------

    \96\ BLS expanded their publication of case and demographic data 
for injury and illness cases involving days of job transfer or 
restriction (DJTR) with the introduction of biennial estimates in 
2021-2022. (https://www.bls.gov/iif/notices/2022/biennial-estimates.htm).
---------------------------------------------------------------------------

IV. OSHA's Underreporting Adjustment--Non-Fatal HRIs
    The best available estimates of the magnitude of the underreporting 
of injuries and illnesses comes from a 2014 study funded by BLS that 
compared State-based surveillance data from California (specifically 
the Workers' Compensation Information System, data from healthcare 
facilities across the State, and Doctors' First Reports of Occupational 
Illness or Injury) to BLS SOII microdata for both carpal tunnel 
syndrome and amputations from 2007-2008 (Joe et al., 2014). In this 
study, researchers linked individual cases in each dataset to the 
corresponding case in other datasets to obtain a better estimate of the 
total number of cases for each outcome occurring in California during 
this time. They found that the State-based data sources contained 5 
times more amputations and 10 times more carpal tunnel syndrome cases 
than were reported in the BLS SOII data. Joe et al. (2014) also found 
that about 30 percent of SOII cases were not captured in the State 
database which suggests that both sources are failing to capture some 
injuries.
    While Joe et al. (2014) was not specific to heat, a more recent 
study from California compared the number of HRI claims in the State's 
Workers' Compensation Information System to the estimated number of 
HRIs reported in BLS SOII for the same years (2009-2017) (Heinzerling 
et al., 2020). Heinzerling et al. found 3-6 times the number of HRI 
cases estimated by SOII in the State's workers' compensation database 
each year. While this study did not match individual cases as was done 
in Joe et al. (2014), it is reasonable to assume that similar to the 
findings in that study, some HRIs that were captured by the SOII data 
were not captured by the State's workers' compensation data. This would 
mean that there are even more cases in the State database that are not 
captured in SOII (which would mean the undercount estimate of 3-6 times 
is an underestimate). It is also possible that the workers' 
compensation database examined by Heinzerling et al. (2020) is missing 
HRIs. In Joe et al., 2014, approximately 54-74 percent of cases 
identified in the healthcare facility data were only found in that 
dataset and 46 percent of cases identified in the Doctors' First 
Reports data were found only in that dataset. This suggests that the 
number of cases Heinzerling et al. (2020) identified in the workers' 
compensation data that they compared to BLS SOII may itself have been 
an undercount.
    Finally, simply comparing the total number of recorded occupational 
fatalities annually to the total number of annual recorded non-fatal 
injuries and illnesses suggests potentially significant underreporting 
of HRIs. For each occupational death in 2022, there were about 965 
medically consulted work-related injuries (4,695 fatalities to

[[Page 70967]]

4,530,000 medically consulted injuries based on data from the National 
Safety Council (NSC, n.d.)). In 2022, for each occupational fatality, 
there were about 639 recordable injuries and illnesses (5,486 
fatalities to 3.5046 million recordable cases (BLS, 2024c; BLS, 
2023b)). This ratio is generally consistent across a number of specific 
causes or types of occupational fatalities and non-fatal injuries and 
illnesses. Similarly, for heat-specific cases, a ratio of 1,000 
emergency department visits and hospitalizations per 1.4 fatalities was 
reported in a 2011 analysis by the Florida Department of Health 
(Florida DOH, 2011; also discussed in Section V.A., Risk Assessment). 
As such, the ratio of heat-related fatalities to HRIs (about 82 HRIs 
for every one fatality) from the data that OSHA is relying on for its 
estimate of benefits indicates an unusually low number of HRIs. Based 
on the reported number of occupational heat-related fatalities (which 
OSHA believes, and research supports, is an underestimate) of 40 per 
year, the expected number of HRIs would be around 38,000 per year 
versus the 3,288 reported annual HRIs (assuming the relationship 
between fatalities and non-fatal injuries and illnesses is similar for 
heat-related fatalities and injuries and illnesses and the all-cause 
mortality and injury and illness numbers).
    Based on these studies, OSHA has preliminary determined that the 
range of estimates reported in Joe et al. (2014) (i.e., 5-10 times more 
cases than in the SOII data) are the best available estimates on the 
magnitude of undercounting of occupational injuries and illnesses by 
BLS SOII. These values are supported by Heinzerling et al. (2020) which 
found 3-6 times the number of HRI cases but which had limitations 
likely leading to an underestimation of the magnitude. OSHA welcomes 
comment on this adjustment, submission of additional data or studies 
that would help the agency refine this estimate, and suggestions on 
alternative methodologies.
V. Underreporting-Adjusted HRIs and Heat-Related Fatalities
    Based on this analysis, OSHA estimates that HRIs are undercounted 
by a factor of 7.5 (mid-point of 5 and 10) and heat-related fatalities 
are undercounted by a factor of 14. Applying these factors to BLS' 
reported 39,450 HRIs and 479 fatalities, OSHA estimates an 
underreporting adjusted total of 295,875 HRIs and a total of 6,706 
heat-related fatalities from 2011 to 2022, an annual average of 24,656 
and 559 per year respectively. Additional values of the undercount--
both higher and lower--are presented later in this section in a 
sensitivity analysis.
III. Monetized Health and Safety Benefits
    As explained in Section V.C., Risk Reduction, OSHA has 
preliminarily determined, based on a review of academic literature on 
the effectiveness of heat injury and illness prevention methods, that 
full compliance with this proposed standard would reduce heat-related 
fatalities by 99.8-100 percent and HRIs by 37-96 percent. For this 
benefits analysis, OSHA is assuming an effectiveness of 95 percent for 
fatalities and 65 percent of HRIs. The effect of different assumptions 
on the outcome of this benefits analysis are discussed below in the 
sensitivity analysis.
    Applying the undercount adjustment to BLS-reported heat-related 
fatalities and HRIs discussed above by factors of 14 and 7.5 
respectively, OSHA estimates that the proposed standard will prevent 
531 heat-related fatalities per year (of the estimated 559 fatalities) 
and 16,027 HRIs per year (of the estimated 24,656 HRIs) under the 
assumptions of 95 percent effectiveness for heat-related fatalities and 
65 percent effectiveness for HRIs.\97\ Using the 2022 estimate of the 
value of a statistical life (VSL) developed by the Department of 
Transportation (DOT) \98\ and converting to 2023 dollars using the GDP 
deflator (BEA, 2024), $13.77 million, OSHA estimates the monetized 
benefits from avoided fatal heat-related incidents in the first year 
would be $7.310 billion. OSHA monetized benefits of avoided HRIs using 
the midpoint of the range of the value of a statistical injury (VSI) 
cited in Viscusi and Gentry (2015), converted to 2023 dollars using the 
GDP deflator, $116,588 per injury.\99\ The estimated monetized benefits 
from avoided HRIs are $1.869 billion per year. Total benefits each year 
for avoided heat-related fatalities and HRIs are $9.179 billion.
---------------------------------------------------------------------------

    \97\ OSHA assumes that the proposed standard is equally 
effective at preventing fatalities and HRIs that are currently 
reported in the economic data and those that are currently 
unreported. The agency welcomes comment on this assumption.
    \98\ Available at https://www.transportation.gov/office-policy/transportation-policy/revised-departmental-guidance-on-valuation-of-a-statistical-life-in-economic-analysis (DOT, 2024). The 2022 
estimate was based on a comprehensive 2021 Department of 
Transportation guidance update, available at https://www.transportation.gov/sites/dot.gov/files/2021-03/DOT%20VSL%20Guidance%20-%202021%20Update.pdf (DOT, 2021).
    \99\ OSHA welcomes comment regarding this VSI estimate and 
whether it is an appropriate value given that HRIs may be less 
severe than other injuries and illnesses typically considered in the 
VSI derivation. The agency welcomes suggestions on alternative VSI 
estimates for HRIs as well as supporting data, methodologies, or 
studies that would help the agency refine this estimate.
---------------------------------------------------------------------------

IV. Additional Unquantified Potential Benefits
    OSHA believes the proposed standard may provide several additional 
potential benefits beyond the avoided direct heat-related fatalities 
and HRIs captured in the monetized health and safety benefits. These 
potential benefits include avoided indirect fatal and non-fatal 
injuries related to heat exposure, increased labor supply, and 
increased utility for employees. The agency's estimate of monetized 
health and safety benefits has not incorporated benefits for these 
factors. The values presented here are shown to demonstrate the 
potential magnitude of these benefits but are highly uncertain and, 
therefore, not incorporated into the main quantified estimate of the 
benefits of this proposed standard.
A. Indirect Fatalities and Non-Fatal Injuries
    As discussed in detail in Section V.A., Risk Assessment, and 
Section IV., Health Effects, workers face additional risks from working 
in hot environments other than the direct physical effects of heat on 
the employee's body. Indirect injuries that are caused by the 
physiological effects of heat stress, but are not themselves, heat 
exhaustion or heat stroke (i.e., falling, motor vehicle accidents, 
etc.). Direct HRIs and fatalities are those caused by the effects of 
heat on the body without the involvement of other factors. The 
underreporting adjustments in the benefits analysis may not capture or 
only capture some of the underreporting of indirect HRIs and heat-
related fatalities. Researchers have used the natural fluctuations in 
temperatures to conduct quasi-experimental studies examining the 
relationship between heat and workers' compensation claims for 
traumatic injuries (Spector et al., 2016; Calkins et al., 2019; 
Dillender, 2019; Park et al., 2021; Negrusa et al., 2024). These 
papers' findings suggest that there may be many workers' compensation 
claims that are heat-related but not coded as such. For instance, Park 
et al. (2021) estimated that approximately 20,000 injuries per year in 
California between 2001 and 2018 were caused by hotter temperatures 
(relative to ``optimal'' temperature). For comparison, for a similar 
time period (2000-2017), Heinzerling et al. (2020) only identified an 
average of 889 HRI workers' compensation claims per year in California 
(a 22-fold difference),

[[Page 70968]]

suggesting that relying on workers' compensation claims for HRIs alone 
does not capture the higher incidence of injuries of other kinds where 
heat may have played a role. OSHA has not included a quantified value 
of potentially avoided indirect heat-related fatalities and non-fatal 
occupational injuries, but these studies suggest that heat may 
contribute to additional impacts on employees and that these impacts 
may be significant. Because of this, the benefits of this proposed 
standard may be greater than what OSHA estimates in the primary 
estimate.
    If the relationship between directly- and indirectly-caused heat-
related non-fatal injuries found in Park et al. (2021) was 
representative of the true relationship, the number of occupational 
direct and indirect heat-related non-fatal injuries may be as high as 
72,000 annually (based on the BLS-reported annual non-fatal injuries of 
3,288 and an estimate of 22 indirect heat-related injuries per 1 direct 
heat-related injury). Assuming the proposed standard prevented 65 
percent of these indirect non-fatal injuries, it might prevent a total 
of 47,000 indirect non-fatal injuries each year. Monetizing those 
avoided injuries would represent about an additional $5.5 billion in 
benefits (using a VSI of $116,588 per avoided injury). If the 
relationship between non-fatal injuries and fatalities seen for 
occupational injuries and fatalities in general of one fatality for 
every 1,000 injuries holds for these accidents, this means that there 
might be 72 indirect heat-related fatalities annually.\100\ Given that 
these are caused by different factors besides heat and so may be 
preventable at lower rates than direct heat-related fatalities, 
assuming preventability equal to the preventability of non-fatal 
injuries, this proposed standard might prevent an additional 46 
indirect heat-related fatalities annually. Monetized, this would mean 
additional benefits of $644 million.
---------------------------------------------------------------------------

    \100\ This calculation uses a more generalized ratio of 
occupational injuries to fatalities than those discussed previously 
based on NSC and BLS data (NSC, n.d.; BLS, 2023b; BLS, 2024c). If 
the NSC-derived ratio of 965 injuries to one fatality were more 
accurate, there could be about 75 indirect heat-related fatalities 
annually. If the BLS-derived ratio of 639 injuries to one fatality 
were correct, the indirect heat-related fatalities could be around 
113 annually.
---------------------------------------------------------------------------

B. Worker Disutility and Decreased Labor Supply
    There is a lengthy economic literature that suggests that humans 
have strong preferences for not being exposed to extreme temperatures. 
Roback (1982) and Sinha et al. (2018) used revealed preference 
techniques and found that most people experience non-trivial direct 
disutility \101\ from exposure to extreme temperatures and that they 
are willing to pay non-trivial amounts to mitigate those exposures 
where they can. Studies of real world responses to extreme temperatures 
including Graff Zivin and Neidell (2014) and Rode et al. (2022) found 
that workers decrease the amount of labor they are willing to supply 
(i.e., for workers who are able to do so, they will shorten their work 
day or choose to not work on a certain day) when temperatures are 
extreme (with a greater decrease in labor supplied when temperatures 
are extremely hot versus when they are extremely cold) suggesting that 
workers prefer to forgo wages rather than be exposed to extreme 
temperatures. In cases where labor markets are imperfectly competitive, 
workers might benefit from this proposed standard because they do not 
have the option to avoid exposure to extreme temperatures, even if they 
were willing to forgo wages (for more on the implications of imperfect 
labor market competition for compensating differentials, see, e.g., 
Burdett and Mortensen, 1998; Sorkin, 2018). While the interventions in 
this proposed standard will not eliminate the need for work to be 
performed in hot environments, to the extent that these interventions 
mitigate some of the physical discomfort caused by heat, employees may 
experience a decrease in the disutility they face due to working in hot 
environments.
---------------------------------------------------------------------------

    \101\ In economic terms, disutility is the negative or harmful 
effects of some activity or economic transaction. In economics, 
individuals are assumed to try to maximize their utility (and 
conversely minimize their disutility).
---------------------------------------------------------------------------

    While an individual's utility or disutility is difficult to 
measure, Li et al. (2020) found that people expressed a willingness to 
pay (WTP) between $2.60 and $4.60 per day to avoid a hot day. WTP may 
not already be satisfied in the labor market as a result of imperfect 
competition, imperfect information, binding minimum wages, or other 
features of the market. This is not perfectly analogous to utility but 
gives a range for the value that individuals place on avoiding 
excessive heat. Assuming a point estimate of a WTP of $3 per day \102\ 
to mitigate the physical discomfort of working in hot environments, all 
employees in the scope of this proposed standard receiving heat 
protections for 30 days on average would equal benefits of $3.236 
billion. Employees in many parts of the country work in hot conditions 
for many more than 30 days, meaning that, if benefits to workers to 
mitigate the negative physical effects of heat that do not rise to the 
level of a heat injury or illness were captured and monetized, the 
benefits of this proposed standard may be even greater than those shown 
by the monetized safety and health benefits.
---------------------------------------------------------------------------

    \102\ This assumes a value on the lower end of what Li et al. 
(2020) estimated since this proposed standard will not entirely 
remove most employees from hot environments. There are arguments to 
be made that this might be an underestimate for a few reasons. 
First, people have a higher WTP to avoid very high temperatures so 
where this proposed standard improves conditions for employees 
exposed to very high temperatures, their WTP might be higher. 
Second, those surveyed by Li et al. (2020) were not necessarily 
workers who were working in high heat. Employee's WTP for heat 
mitigating measures might be higher than a general individual's WTP 
to avoid hot days in general since employees have to perform 
physical labor in those hot environments and because employees have 
less control over workplace factors like resting, clothing choices, 
or the ability to stay inside or to relocate somewhere with air 
conditioning. Finally, those surveyed by Li et al. (2020) may have 
included nonworking individuals who may have a lower income and 
therefore a lower WTP than individuals who are working for wages.
---------------------------------------------------------------------------

    Graff Zivin and Neidell (2014) found that workers with high 
exposure to heat reduced their labor supply by as much as one hour per 
day when the temperatures were above 85[deg]F.\103\ Based on an average 
loaded hourly wage of $43.60 (the average for all at-risk workers in 
the scope of the proposed standard), if employees working in the 
hottest environments (assumed here to be the sum of workers exposed to 
process heat and outdoor workers) supply 5 additional hours of labor 
each over the course of a year, they would cumulatively receive 
additional wages of $3.877 billion. Measures that improve the comfort 
of employees and reduce the negative physical effects of heat could 
easily result in the small increase in labor supply discussed here. As 
mentioned previously, employers benefit when employees produce more so 
the benefits of increased labor supply would be more than just the 
increased wages paid to employees--employers' revenue would increase 
because of increased employee output as well.
---------------------------------------------------------------------------

    \103\ Note that this change in labor supply refers to real world 
effects seen where workers choose to work fewer hours when 
temperatures are excessively hot or cold (e.g., ending their workday 
early, choosing to not work on certain days) and is different from 
the productivity effects of rest breaks discussed elsewhere.
---------------------------------------------------------------------------

V. Uncertainty
    A few factors contribute to uncertainty in the estimates of the 
benefits of this proposed standard including potential underreporting 
of heat-related fatalities and HRIs, uncertainty of the effectiveness 
of the

[[Page 70969]]

interventions required by the proposed standard, and potential benefits 
of improved labor productivity.
A. Underreporting
    As discussed earlier, OSHA believes the number of HRIs and heat-
related fatalities estimated from the BLS data is likely underestimated 
compared to the true number of HRIs and heat-related fatalities in the 
United States. Research suggests that HRIs and heat-related fatalities 
are underreported in multiple datasets (e.g., BLS CFOI, BLS SOII, 
workers' compensation claims data, and hospital discharge data). The 
general underreporting and undercounting of occupational injuries and 
illnesses has been a topic of multiple government reports (e.g., Ruser, 
2008; Miller, 2008; GAO, 2009; Wiatrowski, 2014). While there is a good 
deal of agreement that some level of underreporting exists for 
occupational injuries and illnesses in general and HRIs specifically, 
there is uncertainty regarding the magnitude of underreporting. OSHA 
has adjusted for underreporting of HRIs and heat-related fatalities but 
there remains a wide range of estimates of underreporting in the 
research. There still remains a high level of uncertainty in these 
estimates and the magnitude of underreporting is potentially 
considerably higher than what OSHA has estimated. If the HRIs were 
underreported by a factor of 10 rather than 7.5 (which is plausible 
based on the available evidence) and this proposed standard has the 
same effectiveness, it could prevent about an additional 11,500 HRIs 
which could account for an additional $1.342 billion in benefits.
B. Program Effectiveness
    As explained above, for this benefits analysis, OSHA assumes that 
the proposed standard will be 65 percent effective in curbing HRIs. 
This topic, the relevant literature, and how the agency arrived at its 
estimates of the standard's effectiveness are discussed in-depth in 
Section V.C., Risk Reduction. As discussed previously, OSHA found that 
the literature on this issue lacks certainty. Few studies included a 
concurrent control group, rather most studies looked at rates of HRI 
before and after an intervention in the same group. Studies were 
generally performed on specific industries, or in specific settings, 
and the effectiveness of the intervention might be higher or lower than 
the study average across the firms and employees covered by this 
rulemaking. Additionally, no study tested an intervention that would 
exactly match the controls required by the proposed standard. For 
example, McCarthy et al. (2019) report a 60-90 percent decrease in the 
odds of HRI among municipal outdoor workers in Texas after a Heat 
Stress Awareness Program (HSAP) intervention was implemented in 2011. 
However, this study lacked a control group that received no 
intervention making it difficult to determine if the reported 
effectiveness could be attributed to the intervention. While OSHA 
assumed the effectiveness of the proposed standard in preventing HRIs 
to be on the lower end of what McCarthy et al. (2019) found, there is 
evidence that the effectiveness of heat interventions may be much 
higher than that (See Section V.C., Risk Reduction, for additional 
discussion).
    If the proposed standard were more effective at preventing heat-
related fatalities and HRIs than OSHA estimates in this analysis (and 
based on available evidence this is plausible, see Section V.C., Risk 
Reduction) and prevented all fatalities (100 percent versus 95 percent) 
and 10 percent more HRIs (75 percent versus 65 percent), the proposed 
standard might prevent 28 more fatalities and about 2,500 more non-
fatal injuries and illnesses annually. Monetized, this represents 
approximately an additional $672 million in benefits.
C. Labor Productivity Losses
    As discussed above in section VIII.E.IV.A., OSHA has preliminarily 
determined, based on numerous studies, that there are labor 
productivity losses from working in the heat that can be partially 
recovered through the provision of rest breaks. However, precisely 
defining the magnitude of labor productivity losses that could be 
recuperated under the proposed standard is difficult with the current 
research available. This analysis rests on specific assumptions and is 
dependent on the extent of the available literature, in which heat and 
productivity were assessed in different settings with different break 
policies, but break policies did not vary within the same setting. OSHA 
mentions those impacts here, as well, to acknowledge the uncertainty 
associated with those estimates. This factor is examined in the 
sensitivity analysis in Section VIII.C. Costs of Compliance (section 
VIII.C.VI).
VI. Sensitivity Analysis
    OSHA considers the rate of effectiveness of the various measures of 
this proposed standard a major source of uncertainty in the calculation 
of benefits. OSHA has compiled a sensitivity analysis to illustrate the 
range that could depict the benefits estimate. As shown below in table 
VIII.E.6. for the low estimate, OSHA estimated program effectiveness to 
be 50 percent for HRIs and 90 percent for heat-related fatalities (as 
opposed to the primary estimate of 65 percent effectiveness for HRI 
prevention and 95 percent effectiveness for fatality prevention). For 
the high estimate, OSHA estimated 100 percent effectiveness for the 
prevention of both heat-related fatalities and HRIs by the proposed 
standard (as opposed to the primary estimate of 65 percent 
effectiveness for HRI prevention and 95 percent effectiveness for 
fatality prevention).
    At the 50 percent level of effectiveness, OSHA calculated monetized 
benefits of avoided HRIs of $1.437 billion. At the 90 percent level of 
effectiveness, OSHA calculated monetized benefits of avoided heat-
related fatalities of $6.926 billion. Both estimates use the same VSI 
and VSL discussed above. Total monetized benefits at the 50 and 90 
percent level of effectiveness are $8.363 billion per year.
    At the 100 percent level of effectiveness, the monetized benefits 
of avoided HRIs are $2.875 billion per year. The monetized benefits of 
avoided heat-related fatalities at the same level of effectiveness are 
$7.696 billion. Both estimates use the same VSI and VSL discussed 
above. Total monetized benefits per year for the 100 percent level of 
effectiveness are $10.570 billion.
    The sensitivity analysis also looked at the impact on the estimated 
number of avoided HRIs and heat-related fatalities under different 
assumptions of underreporting, specifically (1) alternative assumptions 
for the underreporting related to HRIs, assuming factors of 2 or 10 or 
no underreporting and (2) alternative assumptions regarding the 
underreporting of heat-related fatalities, assuming that heat-related 
fatalities were underreported by factors of 3 or 15 or not 
underreported at all. The estimated number of avoided HRIs and avoided 
heat-related fatalities under these alternative assumptions of 
underreporting are presented in tables VIII.E.6. and VIII.E.7. with 
OSHA's primary estimate of effectiveness as well as under the low and 
high levels of effectiveness discussed above.
    Total monetized benefits per year from avoided heat-related 
fatalities and HRIs under different assumptions of program 
effectiveness and underreporting are presented in Table VIII.E.8.

[[Page 70970]]



                                   Table VIII.E.6--Sensitivity Analysis--HRIs
----------------------------------------------------------------------------------------------------------------
                                                     Primary estimate
                                                           (65%          Low estimate (50%   High estimate (100%
                                                      effectiveness)      effectiveness)       effectiveness)
----------------------------------------------------------------------------------------------------------------
Cases--No underreporting adjustment...............               2,137               1,644                 3,288
Cases--Low underreporting (2X)....................               4,274               3,288                 6,575
Cases--High underreporting (10X)..................              21,369              16,438                32,875
Cases--Primary estimate underreporting (7.5X).....              16,027              12,328                24,656
Monetized benefits, no underreporting adjustment..        $249,133,988        $191,641,529          $383,283,058
Monetized benefits, low underreporting (2X).......        $498,267,975        $383,283,058          $766,566,116
Monetized benefits, high underreporting (10X).....      $2,491,339,876      $1,916,415,290        $3,832,830,579
Monetized benefits, OSHA primary estimate               $1,868,504,907      $1,437,311,467        $2,874,622,934
 underreporting (7.5X)............................
----------------------------------------------------------------------------------------------------------------
Source: OSHA estimate.


                          Table VIII.E.7--Sensitivity Analysis--Heat-Related Fatalities
----------------------------------------------------------------------------------------------------------------
                                                     Primary estimate
                                                           (95%          Low estimate (90%   High estimate (100%
                                                      effectiveness)      effectiveness)       effectiveness)
----------------------------------------------------------------------------------------------------------------
Cases--No underreporting adjustment...............                37.9                35.9                  39.9
Cases--Low underreporting (3X)....................               113.8               107.8                 119.8
Cases--High underreporting (15X)..................              568.86              538.92                 598.8
Cases--Primary estimate underreporting (14X)......             530.936             502.992                558.88
Monetized benefits, no underreporting adjustment          $522,213,480        $494,728,560          $549,698,400
 underreporting...................................
Monetized benefits, low underreporting (3X).......      $1,566,640,440      $1,484,185,680        $1,649,095,200
Monetized benefits, high underreporting (15X).....      $7,833,202,200      $7,420,928,400        $8,245,476,000
Monetized benefits, primary estimate                    $7,310,988,720      $6,926,199,840        $7,695,777,600
 underreporting (14X).............................
----------------------------------------------------------------------------------------------------------------
Source: OSHA estimate.


                         Table VIII.E.8--Sensitivity Analysis--Total Estimated Benefits
----------------------------------------------------------------------------------------------------------------
                                        Primary
                                    underreporting     No underreporting  Low underreporting         High
                                       estimate                                                 underreporting
----------------------------------------------------------------------------------------------------------------
                                      Monetized Health and Safety Benefits
----------------------------------------------------------------------------------------------------------------
Low Effectiveness...............      $8,363,511,307        $686,370,089      $1,867,468,738      $9,337,343,690
High Effectiveness..............      10,570,400,534         932,981,458       2,415,661,316      12,078,306,579
OSHA Primary Estimate                  9,179,493,627         771,347,468       2,064,908,415      10,324,542,076
 Effectiveness..................
----------------------------------------------------------------------------------------------------------------
Source: OSHA estimate.

VII. Conclusion
    Uncertainty as to the magnitude of underreporting and uncertainty 
as to the effectiveness of the interventions prescribed by this 
proposed standard create substantial uncertainty in the calculation of 
monetized benefits. Additional uncertainty is added by the magnitude of 
labor productivity benefits from the required rest breaks. With the 
caveat of multiple areas of uncertainty, OSHA preliminarily concludes 
that this proposed standard would have an estimated $9.179 billion in 
total annualized benefits.

F. Initial Regulatory Flexibility Analysis, Small Business Regulatory 
Enforcement Fairness Act, and Executive Order 13272 (Proper 
Consideration of Small Entities in Agency Rulemaking)

I. Introduction
    The RFA, 5 U.S.C. 601 et seq., as amended by the Small Business 
Regulatory Enforcement Fairness Act of 1996, Public Law 104-121 (Mar. 
29, 1996), hereafter jointly referred to as the RFA, requires Federal 
agencies to consider the economic impact of a proposed rulemaking on 
small entities. The RFA states that whenever a Federal agency is 
required to publish a general notice of proposed rulemaking, the agency 
must prepare and make available for public comment an initial 
regulatory flexibility analysis (IRFA) (5 U.S.C. 603(a)). Pursuant to 
section 605(b), instead of an IRFA, the head of an agency may certify 
that the proposed rule will not have a significant economic impact on a 
substantial number of small entities. A factual basis must support a 
certification. If the head of an agency makes a certification, the 
agency shall publish such certification in the Federal Register at the 
time of publication of a general notice of proposed rulemaking or at 
the time of publication of the final rule (5 U.S.C. 605(b)).
    To determine whether OSHA can certify that the proposed standard 
for Heat Injury and Illness Prevention in Outdoor and Indoor Work 
Settings will not have a significant economic impact on a substantial 
number of small entities, OSHA has developed a screening test to 
consider the minimum threshold effects of the proposed rule on small 
entities. This screening test is similar in concept to the revenue test 
used in Section VIII.D., Economic Feasibility, to identify minimum 
threshold effects to demonstrate economic feasibility. However, for 
this IRFA the screening test is applied not to all establishments but 
to small entities (called ``small business concerns'' by SBA).
    OSHA is not able to certify that the proposed rule will not result 
in a significant economic impact on a substantial number of small 
entities, thus triggering the need for an IRFA. Under the provisions of 
the RFA, as amended in 1996, each such analysis shall contain:

[[Page 70971]]

    1. A description of the reasons why action by the agency is being 
considered;
    2. A succinct statement of the objectives of, and legal basis for, 
the proposed rule;
    3. A description of and, where feasible, an estimate of the number 
of small entities to which the proposed rule will apply;
    4. A description of the projected reporting, recordkeeping, and 
other compliance requirements of the proposed rule, including an 
estimate of the classes of small entities that will be subject to the 
requirements and the type of professional skills necessary for the 
preparation of the report or record;
    5. An identification, to the extent practicable, of all relevant 
Federal rules which may duplicate, overlap, or conflict with the 
proposed rule; and
    6. A description and discussion of any significant alternatives to 
the proposed rule which accomplish the stated objectives of applicable 
statutes and which minimize any significant economic impact of the 
proposed rule on small entities, such as:
    (a) The establishment of differing compliance or reporting 
requirements or timetables that take into account the resources 
available to small entities;
    (b) The clarification, consolidation, or simplification of 
compliance and reporting requirements under the rule for such small 
entities;
    (c) The use of performance rather than design standards; and
    (d) An exemption from coverage of the rule, or any part thereof, 
for such small entities (5 U.S.C. 603, 607). The RFA further states 
that the required elements of the IRFA may be performed in conjunction 
with or as part of any other agenda or analysis required by any other 
law if such other analysis satisfies the provisions of the IRFA (5 
U.S.C. 605). The remaining sections of this chapter address each of the 
components listed above.
II. Initial Regulatory Flexibility Analysis
A. Description of the Reasons Why Action by the Agency Is Being 
Considered
    Heat is the leading cause of death among all weather-related 
phenomena in the United States. Excessive heat exacerbates existing 
health conditions (e.g., asthma and heart disease) and can cause heat 
stroke and even death if not treated properly and promptly. Heat-
related illnesses are adverse clinical health outcomes that occur due 
to exposure to heat (e.g., heat exhaustion or heat stroke). A heat-
related injury is an injury linked to heat exposure (e.g., a fall that 
occurred while a person was experiencing dizziness related to heat 
exposure).
    Employees in both outdoor and indoor work settings without adequate 
climate controls are at risk of hazardous heat exposure, which may lead 
to heat-related illnesses and injuries (HRIs). Certain heat-generating 
processes, machinery, and equipment (e.g., hot tar ovens, furnaces) can 
also cause HRIs when effective cooling measures are not in place. Some 
groups, such as pregnant employees, may be more likely to experience 
adverse health effects from heat. In contrast, others are 
disproportionately employed in work settings with a higher risk of HRI, 
such as workers of color in essential jobs.
    The BLS SOII estimates that there have been 39,450 work-related 
HRIs involving days away from work between 2011 and 2022, for an 
average of 3,288 HRIs of this severity occurring per year during this 
period. Additionally, according to the BLS CFOI, exposure to 
environmental heat has killed 479 U.S. workers from 2011-2022, with an 
average of 40 fatalities per year during that period. As explained in 
Section V.A., Risk Assessment, these statistics likely do not capture 
the true magnitude and prevalence of heat-related injuries, illnesses, 
and fatalities. OSHA's estimates of the annual incidents of heat-
related fatalities and HRIs and the number the agency expects will be 
avoided by this proposed standard can be found in Section VIII.E., 
Benefits.
    OSHA has developed and published recommendations for heat injury 
and illness prevention. However, in the absence of a Federal standard, 
multiple States have issued regulations to address heat hazards in the 
workplace. Five States have enacted laws that aim to protect employees 
exposed to heat: Minnesota (Minn. R. 5205.0110); California (Cal. Code 
of Regs. title 8, section 3395); Washington (Wash. Admin. Code sections 
296-62-095 through 296-62-09560; 296307-097 through 296-307-09760); 
Oregon (Or. Admin. R. 437-002-0156; Or. Admin. R. 437004-1131); and 
Colorado (7 Colo. Code Regs section 1103-15:3).
    OSHA has received multiple petitions to promulgate a heat injury 
and illness prevention standard in recent years, including in 2018 from 
Public Citizen, on behalf of approximately 130 organizations. Members 
of Congress have also urged OSHA to initiate rulemaking for a Federal 
heat standard.
    In the Federal Register, OSHA published an advance notice of 
proposed rulemaking (ANPRM) for Heat Injury and Illness Prevention in 
Outdoor and Indoor Work Settings on October 27, 2021 (86 FR 59309). 
From the ANPRM, OSHA initiated the rulemaking process to consider a 
heat-related injury and illness prevention standard. The standard would 
set forth the employer's obligations and the measures necessary to 
protect employees to reduce the number of HRIs and fatalities more 
effectively among workers. The goal is to prevent or reduce the number 
of occupational HRIs and fatalities caused by exposure to hazardous 
heat.
    OSHA has developed potential options for various elements of a 
heat-specific standard using: stakeholder comments from the ANPRM; 
academic literature; best practices from State heat-specific standards; 
recommendations from the National Institute for Occupational Safety and 
Health (NIOSH) and the National Advisory Committee on Occupational 
Safety and Health (NACOSH); and other input from experts, stakeholders, 
and the public.
    As described in the benefits analysis in Section VIII.E., Benefits, 
OSHA estimates that approximately 559 heat-related fatalities and 
approximately 24,656 HRIs among employees occur annually. However, as 
explained in that section, OSHA also believes there remains a great 
deal of uncertainty surrounding the extent of underreporting and other 
parameters used in this estimate.
B. Statement of the Objectives of and Legal Basis for the Proposed Rule
    The objective of the proposed standard is to reduce the number of 
HRIs and fatalities due to exposure to hazardous heat occurring among 
employees in the course of their work. This objective would be achieved 
by requiring employers to establish heat injury and illness prevention 
plans (HIIPPs); identify and monitor heat hazards, provide rest breaks, 
adequate water, and training; plan for, and be ready to respond to, 
heat emergencies; and take other steps to ensure that employees can 
perform their duties safely.
    The legal basis for the rulemaking is discussed in depth in Section 
II., Pertinent Legal Authority. In short, Congress enacted the 
Occupational Safety and Health (OSH) Act of 1970 (29 U.S.C. 651 et 
seq.), ``to assure so far as possible every working man and woman in 
the Nation safe and healthful working conditions and to preserve our 
human resources'' (29 U.S.C. 651(b)). To that end, Congress authorized 
the Secretary of Labor ``to set mandatory occupational safety and 
health standards applicable to businesses affecting interstate 
commerce'' (29 U.S.C. 651(b)(3); see also 29 U.S.C. 655(b)).

[[Page 70972]]

    The OSH Act imposes several requirements OSHA must satisfy before 
adopting a safety standard. Among other things, the standard must 
provide a high degree of employee protection, substantially reduce a 
significant risk to workers, be technologically feasible, and be 
economically feasible (see 58 FR 16612, 16614-16 (Mar. 30, 1993); Int'l 
Union, United Auto., Aerospace & Agric. Implement Workers of Am. v. 
OSHA, 37 F.3d 665, 668-69 (D.C. Cir. 1994)). A standard is 
technologically feasible if the protective measures it requires already 
exist, can be brought into existence with available technology, or can 
be created with technology that is reasonably expected to be developed 
(see Am. Iron and Steel Inst. v. OSHA, 939 F.2d 975, 980 (D.C. Cir. 
1991)). In determining economic feasibility, OSHA must consider the 
cost of compliance in an industry rather than on individual employers. 
In its economic analyses, OSHA ``must construct a reasonable estimate 
of compliance costs and demonstrate a reasonable likelihood that these 
costs will not threaten the existence or competitive structure of an 
industry, even if it does portend disaster for some marginal firms'' 
(Am. Iron and Steel Inst., 939 F.2d at 980, quoting United Steelworkers 
of Am. v. Marshall, 647 F.2d 1189, 1272 (D.C. Cir. 1980)).
C. Description and Estimate of the Number of Small Entities to Which 
the Proposed Rule Will Apply
    Section VIII.B., Profile of Affected Industries, of this PEA 
presents OSHA's preliminary analysis of the type and number of small 
entities to which the proposed rule would apply. To estimate the number 
of small entities potentially affected by this rulemaking, OSHA used 
definitions developed by SBA for each sector as well as the definition 
of a small government and small non-profit entity according to the RFA. 
OSHA estimates the proposed rule would affect approximately 2.0 million 
small entities. Across these small entities, roughly 16.2 million 
employees would be protected by the proposed rule. Table VIII.F.1. 
presents counts of small and very small entities, establishments, and 
employees by industry and region.

              Table VIII.F.1--Profile of Small and Very Small Affected Entities, Establishments, and Employees, by Core Industry and Region
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                        Small (SBA/RFA)                                  Very small (<20)
                        Region                         -------------------------------------------------------------------------------------------------
                                                           Entities      Establishments     Employees       Entities      Establishments     Employees
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                           Agriculture, Forestry, and Fishing
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................             475              478             831             466              466             544
Central...............................................          24,294           24,322         149,091          15,065           15,065          55,208
Eastern...............................................          16,193           16,208         115,421          12,736           12,738          53,826
Pacific...............................................             199              199           1,399             138              138           1,082
Southern..............................................          26,346           26,377         169,979          17,326           17,331          62,951
Western...............................................          16,211           16,268         314,889          10,009           10,012          58,338
                                                       -------------------------------------------------------------------------------------------------
    Subtotal..........................................          83,717           83,853         751,608          55,739           55,750         231,950
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                       Building Materials and Equipment Suppliers
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................              14               15             216              27               27             202
Central...............................................           1,192            1,282          25,975           2,192            2,231          18,113
Eastern...............................................           1,999            2,128          40,838           3,358            3,409          27,914
Pacific...............................................              38               41             679              52               52             395
Southern..............................................           1,814            1,946          34,426           2,855            2,898          23,385
Western...............................................           1,509            1,596          28,722           2,311            2,345          18,858
                                                       -------------------------------------------------------------------------------------------------
    Subtotal..........................................           6,566            7,009         130,856          10,795           10,962          88,866
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                   Commercial Kitchens
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................             509              579           4,603             430              432           1,745
Central...............................................          36,119           40,201         472,283          26,822           26,939         130,727
Eastern...............................................          65,298           69,963         724,441          51,676           51,830         233,251
Pacific...............................................           1,282            1,388          16,812             946              949           4,411
Southern..............................................          42,239           47,058         571,817          31,027           31,159         145,802
Western...............................................          38,954           43,511         487,920          29,838           30,051         149,486
                                                       -------------------------------------------------------------------------------------------------
    Subtotal..........................................         184,402          202,700       2,277,876         140,740          141,361         665,422
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                      Construction
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................           2,383            2,400           6,784           2,277            2,279           4,532
Central...............................................         158,425          158,752         562,118         147,997          148,028         315,449
Eastern...............................................         230,158          230,528         840,221         214,268          214,313         467,181
Pacific...............................................           3,308            3,317          15,761           2,986            2,986           8,179
Southern..............................................         163,896          164,295         695,987         149,782          149,827         359,212
Western...............................................         151,930          152,258         602,318         140,362          140,392         322,939
                                                       -------------------------------------------------------------------------------------------------
    Subtotal..........................................         710,101          711,550       2,723,189         657,671          657,825       1,477,491
--------------------------------------------------------------------------------------------------------------------------------------------------------

[[Page 70973]]

 
                                                          Drycleaning and Commercial Laundries
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................              17               19              95              16               17              69
Central...............................................           1,929            2,171           8,814           1,754            1,797           4,391
Eastern...............................................           5,626            5,994          17,624           5,330            5,438          10,761
Pacific...............................................              39               41             313              32               34              83
Southern..............................................           3,087            3,449          12,989           2,843            2,951           7,977
Western...............................................           2,352            2,501           8,319           2,214            2,268           5,138
                                                       -------------------------------------------------------------------------------------------------
    Subtotal..........................................          13,051           14,174          48,155          12,190           12,506          28,419
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                           Landscaping and Facilities Support
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................             105              109           1,938              98               99             860
Central...............................................          11,364           11,974         165,112          10,565           10,796          82,930
Eastern...............................................          18,330           19,096         270,325          17,103           17,308         131,677
Pacific...............................................             223              250           5,027             202              203           2,067
Southern..............................................          12,805           13,271         200,425          11,867           11,974         101,006
Western...............................................           9,634            9,974         152,217           8,953            9,030          77,219
                                                       -------------------------------------------------------------------------------------------------
    Subtotal..........................................          52,461           54,673         795,043          48,789           49,410         395,758
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                 Maintenance and Repair
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................             174              186           1,055             174              176             821
Central...............................................          19,068           19,653         108,461          19,174           19,344          84,101
Eastern...............................................          25,688           26,211         144,821          25,704           25,857         113,180
Pacific...............................................             304              318           1,926             304              306           1,384
Southern..............................................          20,023           20,552         117,782          20,239           20,395          87,092
Western...............................................          15,931           16,477         100,556          16,000           16,166          72,908
                                                       -------------------------------------------------------------------------------------------------
    Subtotal..........................................          81,188           83,397         474,600          81,595           82,245         359,487
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                      Manufacturing
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................             161              180           1,703             141              147             430
Central...............................................          28,332           29,454         617,095          20,447           20,529          95,353
Eastern...............................................          33,582           34,481         611,009          25,312           25,388         112,950
Pacific...............................................             282              288           2,422             248              248             818
Southern..............................................          24,499           25,279         450,901          18,822           18,884          83,417
Western...............................................          24,347           24,818         337,592          19,945           19,989          76,876
                                                       -------------------------------------------------------------------------------------------------
    Subtotal..........................................         111,203          114,500       2,020,722          84,915           85,185         369,844
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                       Oil and Gas
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................              53               61             692              29               29              70
Central...............................................           2,861            3,003          15,645           2,423            2,443           4,948
Eastern...............................................           1,391            1,458           9,518           1,116            1,125           2,497
Pacific...............................................               0                0               0               0                0               0
Southern..............................................          10,562           11,375          87,027           8,658            8,691          17,744
Western...............................................           1,561            1,631           9,034           1,306            1,308           2,807
                                                       -------------------------------------------------------------------------------------------------
    Subtotal..........................................          16,428           17,527         121,915          13,532           13,596          28,065
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                              Postal and Delivery Services
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................              21               33              34              18               18              26
Central...............................................           1,374            1,951          11,199           1,168            1,171           1,544
Eastern...............................................           2,238            3,001          18,998           1,899            1,900           2,351
Pacific...............................................              25               36              56              20               20              27
Southern..............................................           1,965            2,731          17,147           1,709            1,720           2,104
Western...............................................           1,533            2,081          17,285           1,302            1,309           1,733
                                                       -------------------------------------------------------------------------------------------------
    Subtotal..........................................           7,155            9,832          64,719           6,115            6,139           7,785
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                Recreation and Amusement
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................             258              262             836             243              244             407
Central...............................................           9,660            9,978          76,652           8,093            8,131          23,284

[[Page 70974]]

 
Eastern...............................................          14,184           14,593         126,221          11,535           11,573          34,163
Pacific...............................................             176              182           1,996             131              131             387
Southern..............................................           9,058            9,335          79,313           7,510            7,547          22,207
Western...............................................           7,620            7,976          68,703           6,226            6,251          18,228
                                                       -------------------------------------------------------------------------------------------------
    Subtotal..........................................          40,956           42,326         353,720          33,738           33,877          98,674
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                              Sanitation and Waste Removal
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................              17               17             260              16               16             144
Central...............................................             598              613          11,803             519              519           5,716
Eastern...............................................             908              925          21,423             763              765           8,892
Pacific...............................................              13               16             510              10               10             186
Southern..............................................             579              600          13,810             481              482           5,650
Western...............................................             403              416          10,566             333              334           4,111
                                                       -------------------------------------------------------------------------------------------------
    Subtotal..........................................           2,517            2,586          58,372           2,120            2,125          24,699
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                   Telecommunications
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................               0                0               0               4                4              18
Central...............................................               6                6              28             281              303           1,237
Eastern...............................................              11               12             108             370              388           1,356
Pacific...............................................               0                0               0               2                3              13
Southern..............................................              14               16             124             341              361           1,341
Western...............................................              14               14              71             271              286           1,089
                                                       -------------------------------------------------------------------------------------------------
    Subtotal..........................................              46               48             332           1,269            1,344           5,054
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                 Temporary Help Services
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................               3                3             111               2                2              24
Central...............................................             746              785          58,271             487              490           4,506
Eastern...............................................           1,258            1,305          92,651             845              847           7,409
Pacific...............................................               9               10           1,444               5                5              43
Southern..............................................           1,001            1,064          81,872             663              666           5,193
Western...............................................             734              765          47,601             520              525           3,995
                                                       -------------------------------------------------------------------------------------------------
    Subtotal..........................................           3,752            3,933         281,950           2,522            2,537          21,170
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                     Transportation
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................             472              551           2,648             402              407             779
Central...............................................          35,362           35,967         100,567          32,172           32,196          40,920
Eastern...............................................          30,938           31,687         109,558          27,247           27,290          38,381
Pacific...............................................             336              378           3,401             248              252             513
Southern..............................................          30,063           31,185         121,185          26,656           26,726          38,318
Western...............................................          22,303           23,056          77,739          19,941           20,008          26,654
                                                       -------------------------------------------------------------------------------------------------
    Subtotal..........................................         119,474          122,823         415,098         106,667          106,879         145,566
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                        Utilities
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................              56               86             742              34               37             110
Central...............................................           1,169            2,078          18,326             711              760           2,076
Eastern...............................................           1,235            2,285          22,667             835              957           2,177
Pacific...............................................              12               25             105               9                9              28
Southern..............................................           2,393            3,494          28,343           1,911            1,960           4,049
Western...............................................           1,279            1,717          11,810           1,067            1,103           3,123
                                                       -------------------------------------------------------------------------------------------------
    Subtotal..........................................           6,144            9,686          81,995           4,568            4,826          11,564
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                       Warehousing
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................              21               22             126              10               10              17
Central...............................................           2,193            3,078          70,279             732              753           1,639
Eastern...............................................           2,820            3,920         105,756           1,034            1,051           2,412
Pacific...............................................              42               51             449               8                8              34
Southern..............................................           2,570            3,800          87,420             965              975           2,066

[[Page 70975]]

 
Western...............................................           2,035            2,888          67,352             806              820           1,817
                                                       -------------------------------------------------------------------------------------------------
    Subtotal..........................................           9,681           13,759         331,382           3,555            3,618           7,985
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                        Non-Core
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................           1,503            1,582          14,497           1,594            1,620           5,729
Central...............................................         109,785          114,774       1,251,037         117,012          117,910         428,271
Eastern...............................................         175,885          181,593       1,867,095         189,755          190,941         648,153
Pacific...............................................           2,738            2,857          22,687           2,818            2,851           9,578
Southern..............................................         133,234          138,262       1,099,714         147,342          148,376         508,465
Western...............................................         113,249          117,242       1,000,087         122,703          123,582         423,075
                                                       -------------------------------------------------------------------------------------------------
    Subtotal..........................................         536,394          556,310       5,255,118         581,225          585,280       2,023,270
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                          Total
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alaskan...............................................           6,241            6,582          37,172           5,982            6,031          16,526
Central...............................................         444,478          460,042       3,722,756         407,614          409,405       1,300,411
Eastern...............................................         627,742          645,388       5,138,694         590,884          593,119       1,898,531
Pacific...............................................           9,027            9,397          74,988           8,161            8,205          29,227
Southern..............................................         486,148          504,089       3,870,261         450,999          452,925       1,477,979
Western...............................................         411,599          425,189       3,342,781         384,105          385,778       1,268,393
                                                       -------------------------------------------------------------------------------------------------
    Total.............................................       1,985,235        2,050,685      16,186,651       1,847,745        1,855,463       5,991,068
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source: OSHA, based on BLS 2023c; Census Bureau, 2021a; Census Bureau, 2023a; Census Bureau, 2023d; SBA, 2023; USDA, 2019; and USFA, 2023.
Note: Due to rounding, figures in the columns and rows may not sum to the totals shown.

E. Description of the Projected Reporting, Recordkeeping, and Other 
Compliance Requirements of the Proposed Rule
    OSHA calculates costs for small entities, as defined by SBA (SBA, 
2023) and the RFA, and for ``very small'' entities, defined by OSHA as 
those with fewer than 20 employees, in each industry. To estimate costs 
for these small and very small entities, OSHA first calculates for each 
4-digit NAICS industry and State combination, the average one-time cost 
per establishment, average annual cost per establishment, average one-
time cost per employee, and average annual cost per employee for each 
provision. Since OSHA assumes the indoor work area hazard evaluation is 
completed every five years, average per-establishment and average per-
employee costs are taken for the corresponding cost items. OSHA then 
multiplies these estimates by the number of small, affected 
establishments or affected employees at small establishments to derive 
one-time and annual costs for each provision of the proposed standard. 
One-time costs are annualized to determine total annualized costs by 
provision of the proposed standard. This same methodology is applied to 
the very small business analysis.
    Table VIII.F.2. below shows across all provisions of the proposed 
rule, that small entities are estimated to incur annualized costs of 
approximately $3.9 billion for 2.0 million entities while 1.8 million 
very small entities are estimated to incur annualized costs of about 
$2.2 billion. The costs by provision are shown below while the detailed 
discussion of the unit costs, other parameters, and methodology are 
included in Section VIII.C., Costs of Compliance. Requirements at or 
above the high heat trigger (which includes requirements for rest 
breaks) are the most expensive provision for small entities, accounting 
for almost half of overall costs. The second most expensive provision 
of this proposed rule for small entities is the requirements at or 
above the initial heat trigger provision, which accounts for about 12.5 
percent of costs overall.

                 Table VIII.F.2--Total Costs of the Proposed Heat Injury and Illness Prevention Standard by Provision for Small Entities
                                                                         [2023$]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                        Periodic costs annualized                                             Total annualized \a\
            Provision                  One-time    ----------------------------------      Annual       Costs savings  ---------------------------------
                                                           0%               2%                                                 0%               2%
--------------------------------------------------------------------------------------------------------------------------------------------------------
Rule Familiarization.............     $126,197,841               $0               $0               $0               $0      $12,619,784      $14,049,167
Heat Injury and Illness                797,869,328                0                0      142,832,518                0      222,619,451      231,656,540
 Prevention Plan.................
Identifying Heat Hazards.........       51,433,925      216,486,243      202,237,502      270,810,603                0      297,602,620      299,050,963
Requirements at or above the           257,883,589                0                0      651,324,232       35,815,071      641,297,520      644,218,446
 Initial Heat Trigger............
Requirements at or above the High        3,616,156                0                0    6,173,098,461    4,288,986,520    1,884,473,557    1,884,514,515
 Heat Trigger....................
Heat Illness and Emergency             203,967,646                0                0      459,558,305                0      479,955,069      482,265,315
 Response and Planning...........

[[Page 70976]]

 
Training.........................      822,601,053                0                0      216,052,591                0      298,312,696      307,629,910
                                  ----------------------------------------------------------------------------------------------------------------------
    Total........................    2,263,569,538      216,486,243      202,237,502    7,913,676,711    4,324,801,590    3,836,880,698    3,863,384,856
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source: OSHA.
\a\ The total costs with cost savings accounts for the potential labor productivity loss avoided by having more efficient and effective rest breaks
  required by the proposed standard than are currently taken.


              Table VIII.F.3--Total Costs of the Proposed Heat Injury and Illness Prevention Standard by Provision for Very Small Entities
                                                                         [2023$]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                        Periodic costs annualized                                             Total annualized \a\
            Provision                  One-time    ----------------------------------      Annual       Costs savings  ---------------------------------
                                                           0%               2%                                                 0%               2%
--------------------------------------------------------------------------------------------------------------------------------------------------------
Rule Familiarization.............     $114,091,454               $0               $0               $0               $0      $11,409,145      $12,701,405
Heat Injury and Illness                722,235,085                0                0      129,326,342                0      201,549,851      209,730,267
 Prevention Plan.................
Identifying Heat Hazards.........       48,640,027      188,281,796      175,889,421      254,469,418                0      278,161,601      279,465,502
Requirements at or above the           123,616,262                0                0      252,006,494       13,475,322      250,892,798      252,292,941
 Initial Heat Trigger............
Requirements at or above the High        2,654,923                0                0    2,476,140,705    1,705,554,474      770,851,723      770,881,794
 Heat Trigger....................
Heat Illness and Emergency             192,369,277                0                0      433,352,739                0      452,589,667      454,768,543
 Response and Planning...........
Training.........................      609,255,824                0                0      129,732,988                0      190,658,570      197,559,323
                                  ----------------------------------------------------------------------------------------------------------------------
    Total........................    1,812,663,317      188,281,796      175,889,421    3,682,138,934    1,719,029,797    2,163,203,649    2,184,487,809
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source: OSHA.
\a\ The total costs with cost savings accounts for the potential labor productivity loss avoided by having more efficient and effective rest breaks
  required by the proposed standard than are currently taken.

    Table VIII.F.4. presents the average costs per small entity, while 
table VIII.F.5. presents the average costs per very small entity. On 
average, nearly 2.0 million small entities are estimated to incur costs 
of $1,950 annually to comply with the proposed standard. Fishing (NAICS 
1141) are estimated to have the lowest costs of compliance of the 
covered small entities--$461 on average annually to comply with the 
proposed rule. The small entities with the largest costs, Psychiatric 
and Substance Abuse Hospitals (NAICS 6222), would spend an estimated 
$118,974 annually to comply with the proposed standard.
    On average, about 1.8 million very small entities are estimated to 
incur costs of $1,182 annually to comply with the proposed standard. 
The smallest average costs per very small entity are incurred by 
Fishing (NAICS 1141)--estimated to be $459 on average annually to 
comply with the proposed standard. The highest average costs for very 
small establishments are incurred by Specialty (except Psychiatric and 
Substance Abuse) Hospitals (NAICS 6223) and are estimated to be about 
$45,066 annually.
    The potential small entity impacts of the proposed rule were 
derived based on the methodology detailed in Section VIII.D., Economic 
Feasibility. Table VIII.F.5. shows that, while small entities in most 
industries are estimated to have costs that are well below one percent 
of revenue, a few are estimated to experience costs that exceed one 
percent of revenues. Costs as a percentage of revenues for these 
entities vary from less than 0.01 percent for Tobacco Manufacturing 
(NAICS 3122) and Petroleum and Coal Products Manufacturing (NAICS 3241) 
to 2.84 percent for Child Care Services (NAICS 6244). Note that the 
costs in these tables were annualized using a 2 percent discount rate. 
The impacts for very small entities can be seen in table VIII.F.6.
    As with the small entity impact analysis, the very small entity 
impact analysis shows that, in the majority of industries, the average 
impacts per entity are well below the one percent threshold. Impacts 
range from 0.01 percent for a few industries such as Petroleum and Coal 
Products Manufacturing (NAICS 3241), and Motor Vehicle.
    As discussed in depth in Section VIII.D., Economic Feasibility, the 
agency believes some of the estimated impact in some of these 
industries is likely overstated, due to inflexibility in the cost 
analysis regarding the amount of time spent outside in heat in a 
nondiscretionary manner. For example, even if the assumption that these 
employees spend a large percentage of their time outside is realistic 
under normal circumstances, childcare providers and in-person health 
care providers would likely limit their time outside in high heat 
situations if only to protect those in their care. If the costs of 
complying with this proposed standard were onerous, limiting employee 
exposure to the outdoors during times of extreme heat would be a 
costless method to comply with the standard and could possibly result 
in these employers being fully exempt from the standard (e.g., if the 
employer limited employee's outdoor exposure to meet the exemption for 
short duration employee exposure). OSHA's cost estimates did not take 
changes in employee scheduling into account and therefore may have 
overestimated costs to employers whose employees have discretion 
regarding the amount of time they spend outside.
    NAICS 1124 Sheep and Goat Farming and NAICS 1129 Other Animal 
Production are both heavily weighted to very small family-owned farms 
(USDA,

[[Page 70977]]

2019). Due to a Congressional budget rider, OSHA is not able to expend 
funds on enforcement activities for small farms. Only about 5 percent 
of sheep and goat farms and 12 percent of combined Other Animal 
Production and Aquaculture are something other than family-owned farms 
(i.e., partnerships or corporations). (Given the economies of scale 
necessary for aquaculture, it's likely that these account for more of 
the corporate farms in the combined Other Animal Production and 
Aquaculture data meaning more farms in NAICS 1129 may be family-owned 
farms than appear to be in the combined data.) Based on the Census of 
Agriculture, about 20,000 of about 79,000 total sheep and goat farms 
have hired labor and those have 2 hired laborers on average. For other 
animal production and aquaculture combined, about 35,000 farms out of 
about 190,000 total farms report having hired labor and have an average 
of 3.5 hire laborers. Based on the size and organization of these 
farms, it is unlikely OSHA would be enforcing this standard on those 
industries so they would not incur compliance costs. OSHA welcomes 
feedback on this analysis of the impact on small and very small 
entities
    The costs of this proposed standard are largely employee-based and 
the agency has not found there to be feasibility concerns for entities 
of any size. Therefore, the agency believes that including large non-
profits in the profile of SBA/RFA defined small entities would not 
alter the findings of the Initial Regulatory Flexibility Analysis. OSHA 
welcomes comment regarding the inclusion of large non-profits in the 
profile of SBA/RFA defined small entities.

           Table VIII.F.4--Economic Impacts on Small Entities Affected by the Proposed Standard With Costs Calculated Using a 2% Discount Rate
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                              Average
                                                                                              Total         annualized        Average      Costs as % of
                NAICS                              Industry                 Entities        annualized       cost per       revenue per       revenue
                                                                                              costs           entity          entity
--------------------------------------------------------------------------------------------------------------------------------------------------------
1111................................  Oilseed and Grain Farming........          12,511      $13,585,428          $1,086        $759,359            0.14
1112................................  Vegetable and Melon Farming......           2,127        9,980,549           4,693       1,153,664            0.41
1113................................  Fruit and Tree Nut Farming.......           6,121       14,284,547           2,334         682,745            0.34
1114................................  Greenhouse, Nursery, and                    2,720       12,359,299           4,544         741,146            0.61
                                       Floriculture Production.
1119................................  Other Crop Farming...............           9,564       15,497,239           1,620         282,465            0.57
1121................................  Cattle Ranching and Farming......          18,428       28,781,484           1,562         700,078            0.22
1122................................  Hog and Pig Farming..............           1,048        2,182,612           2,082       2,601,611            0.08
1123................................  Poultry and Egg Production.......           2,278        4,700,946           2,064       2,939,009            0.07
1124................................  Sheep and Goat Farming...........           1,548        2,393,222           1,546          88,910            1.74
1125................................  Aquaculture......................             160          616,482           3,859       1,133,734            0.34
1129................................  Other Animal Production..........           4,913        7,999,112           1,628         115,067            1.41
1131................................  Timber Tract Operations..........             442          439,946             996       1,501,147            0.07
1132................................  Forest Nurseries and Gathering of             150          152,566           1,017         790,399            0.13
                                       Forest Products.
1133................................  Logging..........................           7,980        7,648,751             958       1,563,286            0.06
1141................................  Fishing..........................           2,432        1,113,045             458         853,204            0.05
1142................................  Hunting and Trapping.............             351          374,292           1,066         799,221            0.13
1151................................  Support Activities for Crop                 4,648        5,853,520           1,259       2,707,767            0.05
                                       Production.
1152................................  Support Activities for Animal               4,640        3,376,198             728         506,802            0.14
                                       Production.
1153................................  Support Activities for Forestry..           1,658        1,398,749             844       1,111,045            0.08
2111................................  Oil and Gas Extraction...........           5,307       16,476,736           3,105      26,579,145            0.01
2131................................  Support Activities for Mining....          10,921       43,981,568           4,027       3,821,423            0.11
2211................................  Electric Power Generation,                  2,058       28,171,559          13,690      76,221,412            0.02
                                       Transmission and Distribution.
2212................................  Natural Gas Distribution.........             418        3,527,573           8,436      70,106,856            0.01
2213................................  Water, Sewage and Other Systems..           3,668        7,573,926           2,065       1,410,992            0.15
2361................................  Residential Building Construction         171,099      106,947,179             625       1,421,852            0.04
2362................................  Nonresidential Building                    40,735       62,520,995           1,535       6,719,320            0.02
                                       Construction.
2371................................  Utility System Construction......          16,774       34,191,049           2,038       3,633,655            0.06
2372................................  Land Subdivision.................           4,805        3,170,977             660       1,877,172            0.04
2373................................  Highway, Street, and Bridge                 8,285       17,087,777           2,062       6,724,608            0.03
                                       Construction.
2379................................  Other Heavy and Civil Engineering           4,056        6,569,839           1,620       3,024,764            0.05
                                       Construction.
2381................................  Foundation, Structure, and                 91,279      125,277,109           1,372       1,699,487            0.08
                                       Building Exterior Contractors.
2382................................  Building Equipment Contractors...         177,612      233,824,679           1,316       1,621,258            0.08
2383................................  Building Finishing Contractors...         114,496      106,453,318             930       1,078,107            0.09
2389................................  Other Specialty Trade Contractors          68,126       72,672,079           1,067       1,929,027            0.06
3111................................  Animal Food Manufacturing........             636        1,601,425           2,520      24,357,224            0.01
3112................................  Grain and Oilseed Milling........             250        1,211,561           4,854      62,037,403            0.01
3113................................  Sugar and Confectionery Product               868        2,204,453           2,539       9,556,299            0.03
                                       Manufacturing.
3114................................  Fruit and Vegetable Preserving                743        3,725,663           5,016      25,690,434            0.02
                                       and Specialty Food Manufacturing.
3115................................  Dairy Product Manufacturing......             588        2,637,411           4,484      49,929,979            0.01
3116................................  Animal Slaughtering and                     1,456       12,280,924           8,438      38,292,294            0.02
                                       Processing.
3117................................  Seafood Product Preparation and               221          902,567           4,087      22,008,470            0.02
                                       Packaging.
3118................................  Bakeries and Tortilla                       5,471       11,517,147           2,105       3,818,211            0.06
                                       Manufacturing.
3119................................  Other Food Manufacturing.........           1,655        5,268,917           3,183      16,374,321            0.02
3121................................  Beverage Manufacturing...........           4,226        6,542,557           1,548       8,758,819            0.02
3122................................  Tobacco Manufacturing............              58          515,881           8,848     182,294,825            0.00
3131................................  Fiber, Yarn, and Thread Mills....             102        1,037,014          10,139      19,374,286            0.05
3132................................  Fabric Mills.....................             345        1,937,288           5,609      12,945,642            0.04
3133................................  Textile and Fabric Finishing and              378        1,346,267           3,565       7,871,921            0.05
                                       Fabric Coating Mills.
3141................................  Textile Furnishings Mills........             769        2,410,151           3,134       5,547,861            0.06
3149................................  Other Textile Product Mills......           1,981        2,870,758           1,449       2,012,712            0.07
3152................................  Cut and Sew Apparel Manufacturing           1,485        1,708,817           1,151         907,132            0.13
3159................................  Apparel Accessories and Other                 279          488,329           1,750       1,772,440            0.10
                                       Apparel Manufacturing.
3161................................  Leather and Hide Tanning and                   75           78,767           1,048       6,384,614            0.02
                                       Finishing.
3162................................  Footwear Manufacturing...........             102          410,499           4,029       5,074,485            0.08
3211................................  Sawmills and Wood Preservation...           1,425        5,001,937           3,510       7,582,835            0.05
3212................................  Veneer, Plywood, and Engineered               169        1,273,144           7,533      21,682,868            0.03
                                       Wood Product Manufacturing.

[[Page 70978]]

 
3219................................  Other Wood Product Manufacturing.           4,412       11,586,726           2,626       4,072,371            0.06
3221................................  Pulp, Paper, and Paperboard Mills              35          855,082          24,193     136,863,576            0.02
3222................................  Converted Paper Product                     1,264        6,774,484           5,360      24,890,031            0.02
                                       Manufacturing.
3231................................  Printing and Related Support               12,027       11,573,349             962       2,522,782            0.04
                                       Activities.
3241................................  Petroleum and Coal Products                   464        3,199,326           6,895     177,980,216            0.00
                                       Manufacturing.
3251................................  Basic Chemical Manufacturing.....             642        4,655,288           7,251      78,530,261            0.01
3252................................  Resin, Synthetic Rubber, and                  530        4,077,855           7,695      52,682,176            0.01
                                       Artificial and Synthetic Fibers
                                       and Filaments Manufacturing.
3253................................  Pesticide, Fertilizer, and Other              355        1,140,904           3,217      18,940,264            0.02
                                       Agricultural Chemical
                                       Manufacturing.
3254................................  Pharmaceutical and Medicine                   925        5,779,821           6,251      51,766,648            0.01
                                       Manufacturing.
3255................................  Paint, Coating, and Adhesive                  705        2,479,397           3,516      16,249,794            0.02
                                       Manufacturing.
3256................................  Soap, Cleaning Compound, and                1,002        3,477,371           3,470      17,908,986            0.02
                                       Toilet Preparation Manufacturing.
3259................................  Other Chemical Product and                    872        2,542,871           2,916      12,165,378            0.02
                                       Preparation Manufacturing.
3261................................  Plastics Product Manufacturing...           4,134       19,980,060           4,833      13,921,131            0.03
3262................................  Rubber Product Manufacturing.....             699        3,192,709           4,565      12,772,546            0.04
3271................................  Clay Product and Refractory                   463        1,199,726           2,590       5,587,274            0.05
                                       Manufacturing.
3272................................  Glass and Glass Product                       706        1,989,379           2,819       6,976,531            0.04
                                       Manufacturing.
3273................................  Cement and Concrete Product                 2,173        8,394,899           3,863       8,676,117            0.04
                                       Manufacturing.
3274................................  Lime and Gypsum Product                        74          303,318           4,126      15,209,592            0.03
                                       Manufacturing.
3279................................  Other Nonmetallic Mineral Product           1,369        3,198,469           2,336       5,186,460            0.05
                                       Manufacturing.
3311................................  Iron and Steel Mills and                      191        2,633,059          13,753     115,596,140            0.01
                                       Ferroalloy Manufacturing.
3312................................  Steel Product Manufacturing from              246        1,720,852           6,991      28,374,263            0.02
                                       Purchased Steel.
3313................................  Alumina and Aluminum Production               155        1,282,335           8,290      35,439,130            0.02
                                       and Processing.
3314................................  Nonferrous Metal (except                      309        1,616,110           5,227      39,316,152            0.01
                                       Aluminum) Production and
                                       Processing.
3315................................  Foundries........................             691        2,989,596           4,329      11,281,321            0.04
3321................................  Forging and Stamping.............             991        2,784,200           2,810      10,193,180            0.03
3322................................  Cutlery and Handtool                          529          928,777           1,755       5,517,119            0.03
                                       Manufacturing.
3323................................  Architectural and Structural                5,974       16,517,707           2,765       5,735,883            0.05
                                       Metals Manufacturing.
3324................................  Boiler, Tank, and Shipping                    589        2,689,023           4,567      12,577,513            0.04
                                       Container Manufacturing.
3325................................  Hardware Manufacturing...........             272          770,518           2,836       8,866,155            0.03
3326................................  Spring and Wire Product                       492        1,152,112           2,340       6,269,990            0.04
                                       Manufacturing.
3327................................  Machine Shops; Turned Product;             11,032       15,208,419           1,379       2,901,748            0.05
                                       and Screw, Nut, and Bolt
                                       Manufacturing.
3328................................  Coating, Engraving, Heat                    2,521        5,835,961           2,315       4,178,955            0.06
                                       Treating, and Allied Activities.
3329................................  Other Fabricated Metal Product              2,806        7,766,243           2,767       7,493,462            0.04
                                       Manufacturing.
3331................................  Agriculture, Construction, and              1,247        5,944,680           4,766      18,417,556            0.03
                                       Mining Machinery Manufacturing.
3332................................  Industrial Machinery                          425        1,030,865           2,425      10,195,646            0.02
                                       Manufacturing.
3334................................  Ventilation, Heating, Air-                    699        3,921,041           5,609      15,601,508            0.04
                                       Conditioning, and Commercial
                                       Refrigeration Equipment
                                       Manufacturing.
3335................................  Metalworking Machinery                      3,010        4,202,594           1,396       4,357,322            0.03
                                       Manufacturing.
3336................................  Engine, Turbine, and Power                    337        1,582,741           4,698      25,365,617            0.02
                                       Transmission Equipment
                                       Manufacturing.
3339................................  Other General Purpose Machinery             1,762        5,979,770           3,394      12,034,903            0.03
                                       Manufacturing.
3341................................  Computer and Peripheral Equipment             415          490,089           1,182       8,911,705            0.01
                                       Manufacturing.
3342................................  Communications Equipment                      547        1,256,142           2,294      13,522,113            0.02
                                       Manufacturing.
3343................................  Audio and Video Equipment                     219          262,564           1,198       5,604,208            0.02
                                       Manufacturing.
3344................................  Semiconductor and Other                     1,680        4,552,187           2,709      13,079,398            0.02
                                       Electronic Component
                                       Manufacturing.
3345................................  Navigational, Measuring,                    2,157        4,626,878           2,145      12,820,769            0.02
                                       Electromedical, and Control
                                       Instruments Manufacturing.
3352................................  Household Appliance Manufacturing             101          332,021           3,290      14,304,913            0.02
3353................................  Electrical Equipment                          852        2,906,501           3,411      10,715,020            0.03
                                       Manufacturing.
3359................................  Other Electrical Equipment and                752        2,497,573           3,319      12,404,672            0.03
                                       Component Manufacturing.
3361................................  Motor Vehicle Manufacturing......              23           51,856           2,260      58,221,416            0.00
3362................................  Motor Vehicle Body and Trailer                803        4,874,596           6,071      15,741,094            0.04
                                       Manufacturing.
3363................................  Motor Vehicle Parts Manufacturing           1,978       13,487,337           6,817      32,394,740            0.02
3364................................  Aerospace Product and Parts                   646        3,977,519           6,160      29,941,829            0.02
                                       Manufacturing.
3365................................  Railroad Rolling Stock                         74          567,108           7,707      33,655,605            0.02
                                       Manufacturing.
3366................................  Ship and Boat Building...........             658        7,118,392          10,818      14,164,896            0.08
3369................................  Other Transportation Equipment                392          641,075           1,635       6,718,062            0.02
                                       Manufacturing.
3371................................  Household and Institutional                 4,766        9,401,064           1,972       2,859,010            0.07
                                       Furniture and Kitchen Cabinet
                                       Manufacturing.
3372................................  Office Furniture (including                 1,690        3,989,090           2,360       5,125,287            0.05
                                       Fixtures) Manufacturing.
3379................................  Other Furniture Related Product               326        1,166,170           3,581       8,591,445            0.04
                                       Manufacturing.
3391................................  Medical Equipment and Supplies              4,621        7,495,312           1,622       4,733,183            0.03
                                       Manufacturing.
3399................................  Other Miscellaneous Manufacturing           8,582       11,161,673           1,301       2,660,648            0.05
4231................................  Motor Vehicle and Motor Vehicle             1,544       11,511,623           7,456       8,053,146            0.09
                                       Parts and Supplies Merchant
                                       Wholesalers.
4232................................  Furniture and Home Furnishing               1,077        5,781,729           5,367       5,828,655            0.09
                                       Merchant Wholesalers.
4233................................  Lumber and Other Construction                 993        5,631,821           5,671       6,885,143            0.08
                                       Materials Merchant Wholesalers.
4234................................  Professional and Commercial                 2,259       10,168,859           4,501       5,929,082            0.08
                                       Equipment and Supplies Merchant
                                       Wholesalers.

[[Page 70979]]

 
4235................................  Metal and Mineral (except                     709        4,763,004           6,715      13,288,617            0.05
                                       Petroleum) Merchant Wholesalers.
4236................................  Household Appliances and                    1,907       11,364,290           5,960       8,540,329            0.07
                                       Electrical and Electronic Goods
                                       Merchant Wholesalers.
4237................................  Hardware, and Plumbing and                  1,026        5,820,745           5,674       6,361,789            0.09
                                       Heating Equipment and Supplies
                                       Merchant Wholesalers.
4238................................  Machinery, Equipment, and                   4,033       29,834,160           7,398       5,737,517            0.13
                                       Supplies Merchant Wholesalers.
4239................................  Miscellaneous Durable Goods                 2,831       10,561,663           3,731       5,222,434            0.07
                                       Merchant Wholesalers.
4241................................  Paper and Paper Product Merchant              717        3,784,639           5,277       5,821,550            0.09
                                       Wholesalers.
4242................................  Drugs and Druggists' Sundries                 662        4,340,575           6,561      10,574,055            0.06
                                       Merchant Wholesalers.
4243................................  Apparel, Piece Goods, and Notions             386        1,344,807           3,483       5,167,182            0.07
                                       Merchant Wholesalers.
4244................................  Grocery and Related Product                 2,662       15,934,090           5,986      10,630,078            0.06
                                       Merchant Wholesalers.
4245................................  Farm Product Raw Material                     325        2,641,457           8,119      23,756,996            0.03
                                       Merchant Wholesalers.
4246................................  Chemical and Allied Products                  809        4,315,458           5,336       8,980,738            0.06
                                       Merchant Wholesalers.
4247................................  Petroleum and Petroleum Products              376        3,206,820           8,522      61,864,570            0.01
                                       Merchant Wholesalers.
4248................................  Beer, Wine, and Distilled                     326        3,172,050           9,724      13,306,719            0.07
                                       Alcoholic Beverage Merchant
                                       Wholesalers.
4249................................  Miscellaneous Nondurable Goods              2,124       10,353,521           4,876       5,895,079            0.08
                                       Merchant Wholesalers.
4251................................  Wholesale Trade Agents and                  3,749        9,368,912           2,499      12,764,272            0.02
                                       Brokers.
4411................................  Automobile Dealers...............           6,500       37,276,607           5,735      15,961,277            0.04
4412................................  Other Motor Vehicle Dealers......             955        3,490,111           3,656       5,414,403            0.07
4441................................  Building Material and Supplies                544        1,021,683           1,877       2,831,193            0.07
                                       Dealers.
4451................................  Grocery and Convenience Retailers           6,886       22,913,996           3,328       3,311,379            0.10
4452................................  Specialty Food Retailers.........           1,180        2,429,585           2,059       1,053,778            0.20
4811................................  Scheduled Air Transportation.....             727       10,339,037          14,225      97,899,634            0.01
4812................................  Nonscheduled Air Transportation..           1,637        3,179,136           1,942       6,496,273            0.03
4821................................  Rail Transportation..............             113           78,448             697       1,132,927            0.06
4831................................  Deep Sea, Coastal, and Great                  606        2,154,113           3,553      16,994,169            0.02
                                       Lakes Water Transportation.
4832................................  Inland Water Transportation......             410        1,791,814           4,371       6,386,189            0.07
4841................................  General Freight Trucking.........          55,843       50,365,637             902       1,458,914            0.06
4842................................  Specialized Freight Trucking.....          39,386       41,886,506           1,063       1,812,364            0.06
4851................................  Urban Transit Systems............             513          590,618           1,151       2,151,325            0.05
4852................................  Interurban and Rural Bus                      488          896,937           1,837       2,488,321            0.07
                                       Transportation.
4853................................  Taxi and Limousine Service.......           6,453        7,243,177           1,122         862,937            0.13
4854................................  School and Employee Bus                     2,232        3,191,204           1,430       2,019,525            0.07
                                       Transportation.
4855................................  Charter Bus Industry.............             978        1,507,466           1,541       2,813,587            0.05
4859................................  Other Transit and Ground                    3,856        3,185,344             826       1,343,491            0.06
                                       Passenger Transportation.
4861................................  Pipeline Transportation of Crude               70          347,281           4,984      28,045,336            0.02
                                       Oil.
4862................................  Pipeline Transportation of                     59           90,847           1,528      15,269,599            0.01
                                       Natural Gas.
4869................................  Other Pipeline Transportation....              71          269,120           3,788      22,870,110            0.02
4871................................  Scenic and Sightseeing                        572        1,034,717           1,808       1,542,634            0.12
                                       Transportation, Land.
4872................................  Scenic and Sightseeing                      1,479        2,781,692           1,881         961,471            0.20
                                       Transportation, Water.
4879................................  Scenic and Sightseeing                        229          354,470           1,551       1,442,518            0.11
                                       Transportation, Other.
4881................................  Support Activities for Air                  3,639        7,427,615           2,041       2,726,627            0.07
                                       Transportation.
4882................................  Support Activities for Rail                   494        1,414,555           2,861       3,694,856            0.08
                                       Transportation.
4883................................  Support Activities for Water                1,852        6,207,901           3,353       4,619,864            0.07
                                       Transportation.
4884................................  Support Activities for Road                 9,012        6,993,625             776       1,019,225            0.08
                                       Transportation.
4885................................  Freight Transportation                     12,925       18,974,056           1,468       2,467,206            0.06
                                       Arrangement.
4889................................  Other Support Activities for                1,387        1,669,460           1,203       1,765,588            0.07
                                       Transportation.
4921................................  Couriers and Express Delivery               3,724       12,926,412           3,471       9,170,589            0.04
                                       Services.
4922................................  Local Messengers and Local                  3,431        3,012,249             878       1,312,866            0.07
                                       Delivery.
4931................................  Warehousing and Storage..........           9,681       56,004,514           5,785       3,692,460            0.16
5121................................  Motion Picture and Video                    2,568        7,638,794           2,975       1,544,741            0.19
                                       Industries.
5122................................  Sound Recording Industries.......             466          946,190           2,032       1,914,032            0.11
5174................................  Satellite Telecommunications.....              46          165,892           3,602       3,473,723            0.10
5182................................  Computing Infrastructure                    1,352        3,731,170           2,759       2,821,642            0.10
                                       Providers, Data Processing, Web
                                       Hosting, and Related Services.
5221................................  Depository Credit Intermediation.           1,562       21,857,409          13,995      15,334,364            0.09
5222................................  Nondepository Credit                        1,085        3,521,500           3,245       2,825,317            0.11
                                       Intermediation.
5223................................  Activities Related to Credit                1,822        4,068,120           2,232       1,274,881            0.18
                                       Intermediation.
5232................................  Securities and Commodity                        1           26,178          39,745     753,808,884            0.01
                                       Exchanges.
5239................................  Other Financial Investment                  1,542        3,322,810           2,154       3,014,962            0.07
                                       Activities.
5241................................  Insurance Carriers...............             724        7,767,572          10,729      64,751,762            0.02
5242................................  Agencies, Brokerages, and Other            18,002       37,871,610           2,104         884,543            0.24
                                       Insurance Related Activities.
5251................................  Insurance and Employee Benefit                161          187,816           1,164         860,458            0.14
                                       Funds.
5259................................  Other Investment Pools and Funds.             122          253,899           2,075       1,915,830            0.11
5311................................  Lessors of Real Estate...........          13,445       32,370,835           2,408       1,498,519            0.16
5312................................  Offices of Real Estate Agents and          14,553       27,775,521           1,909         848,299            0.22
                                       Brokers.
5313................................  Activities Related to Real Estate          10,787       33,316,314           3,088         865,500            0.36
5321................................  Automotive Equipment Rental and               567        2,987,344           5,267       2,647,455            0.20
                                       Leasing.
5322................................  Consumer Goods Rental............           1,185        5,301,598           4,475       1,093,599            0.41
5323................................  General Rental Centers...........             318        1,344,257           4,222       1,436,198            0.29
5324................................  Commercial and Industrial                   1,171        5,466,318           4,667       3,114,198            0.15
                                       Machinery and Equipment Rental
                                       and Leasing.

[[Page 70980]]

 
5331................................  Lessors of Nonfinancial                       315          671,532           2,130       3,900,891            0.05
                                       Intangible Assets (except
                                       Copyrighted Works).
5411................................  Legal Services...................          23,897       49,298,948           2,063       1,105,731            0.19
5412................................  Accounting, Tax Preparation,               15,652       36,586,403           2,338         715,353            0.33
                                       Bookkeeping, and Payroll
                                       Services.
5413................................  Architectural, Engineering, and            12,833       75,874,312           5,913       1,482,804            0.40
                                       Related Services.
5414................................  Specialized Design Services......           4,402       11,949,232           2,715         783,080            0.35
5415................................  Computer Systems Design and                16,220       39,798,676           2,454       1,363,070            0.18
                                       Related Services.
5416................................  Management, Scientific, and                22,491       62,683,511           2,787         917,797            0.30
                                       Technical Consulting Services.
5417................................  Scientific Research and                     2,115       15,224,604           7,199       5,734,418            0.13
                                       Development Services.
5418................................  Advertising, Public Relations,              4,587       16,632,694           3,626       1,610,062            0.23
                                       and Related Services.
5419................................  Other Professional, Scientific,             8,774       45,327,608           5,166       1,037,261            0.50
                                       and Technical Services.
5511................................  Management of Companies and                   932        7,466,268           8,009       7,794,296            0.10
                                       Enterprises.
5611................................  Office Administrative Services...           4,204       10,143,593           2,413       1,807,749            0.13
5612................................  Facilities Support Services......             296        3,898,123          13,148       4,474,249            0.29
5613................................  Employment Services..............           3,752       42,559,048          11,344       2,963,924            0.38
5614................................  Business Support Services........           3,342        5,943,802           1,778       1,306,752            0.14
5615................................  Travel Arrangement and                      1,972        3,129,421           1,587       1,663,607            0.10
                                       Reservation Services.
5616................................  Investigation and Security                  2,773       25,002,454           9,018       1,245,244            0.72
                                       Services.
5617................................  Services to Buildings and                  26,019      112,901,810           4,339         671,194            0.65
                                       Dwellings.
5619................................  Other Support Services...........           2,399        7,136,600           2,975       1,533,830            0.19
5621................................  Waste Collection.................           1,078        2,523,921           2,342       3,245,312            0.07
5622................................  Waste Treatment and Disposal.....             181          743,227           4,112       3,879,488            0.11
5629................................  Remediation and Other Waste                 1,259        6,361,525           5,055       2,114,365            0.24
                                       Management Services.
6111................................  Elementary and Secondary Schools.           2,856       34,194,636          11,975       4,338,191            0.28
6112................................  Junior Colleges..................              61          567,155           9,272       7,096,235            0.13
6113................................  Colleges, Universities, and                   178          641,408           3,603       3,148,365            0.11
                                       Professional Schools.
6114................................  Business Schools and Computer and           1,150        2,051,773           1,785       1,184,543            0.15
                                       Management Training.
6115................................  Technical and Trade Schools......           1,020        3,125,752           3,063       1,475,233            0.21
6116................................  Other Schools and Instruction....           7,124       15,777,099           2,215         471,098            0.47
6117................................  Educational Support Services.....           1,184        2,055,225           1,736         994,278            0.17
6211................................  Offices of Physicians............           7,538       16,396,965           2,175       1,557,548            0.14
6212................................  Offices of Dentists..............           5,517       15,448,753           2,800       1,107,348            0.25
6213................................  Offices of Other Health                     5,985       13,236,859           2,212         610,067            0.36
                                       Practitioners.
6214................................  Outpatient Care Centers..........             799        6,631,683           8,303       3,531,393            0.24
6215................................  Medical and Diagnostic                        326        1,639,918           5,023       2,880,366            0.17
                                       Laboratories.
6216................................  Home Health Care Services........           1,021       21,196,909          20,756       1,947,504            1.07
6219................................  Other Ambulatory Health Care                  290        2,399,519           8,280       2,122,696            0.39
                                       Services.
6221................................  General Medical and Surgical                   58        3,146,213          54,588      31,988,544            0.17
                                       Hospitals.
6222................................  Psychiatric and Substance Abuse                10        1,136,474         118,967      26,840,059            0.44
                                       Hospitals.
6223................................  Specialty (except Psychiatric and               6          408,435          64,547      24,345,151            0.27
                                       Substance Abuse) Hospitals.
6231................................  Nursing Care Facilities (Skilled              377       15,692,040          41,623       7,737,051            0.54
                                       Nursing Facilities).
6232................................  Residential Intellectual and                  454       12,424,041          27,345       2,746,969            1.00
                                       Developmental Disability, Mental
                                       Health, and Substance Abuse
                                       Facilities.
6233................................  Continuing Care Retirement                    779       13,425,442          17,232       2,104,725            0.82
                                       Communities and Assisted Living
                                       Facilities for the Elderly.
6239................................  Other Residential Care Facilities             136        3,155,732          23,216       2,165,006            1.07
6241................................  Individual and Family Services...           2,496       39,826,256          15,956       1,571,030            1.02
6242................................  Community Food and Housing, and               480        5,254,947          10,949       2,633,784            0.42
                                       Emergency and Other Relief
                                       Services.
6243................................  Vocational Rehabilitation                     172        4,469,310          25,964       2,335,393            1.11
                                       Services.
6244................................  Child Care Services..............           2,687       51,565,482          19,189         676,561            2.84
7111................................  Performing Arts Companies........           4,679        5,483,031           1,172       1,560,279            0.08
7112................................  Spectator Sports.................           2,011        2,409,683           1,198       2,328,568            0.05
7113................................  Promoters of Performing Arts,               4,046        5,398,753           1,334       2,099,056            0.06
                                       Sports, and Similar Events.
7114................................  Agents and Managers for Artists,            2,119        2,111,109             996       1,445,877            0.07
                                       Athletes, Entertainers, and
                                       Other Public Figures.
7115................................  Independent Artists, Writers, and          15,342       14,460,165             942         835,413            0.11
                                       Performers.
7121................................  Museums, Historical Sites, and              3,845        6,836,964           1,778       2,394,793            0.07
                                       Similar Institutions.
7131................................  Amusement Parks and Arcades......           1,742        3,288,557           1,888       1,040,189            0.18
7132................................  Gambling Industries..............           1,000        2,273,300           2,272       5,012,918            0.05
7139................................  Other Amusement and Recreation             34,659       51,264,046           1,479       1,051,729            0.14
                                       Industries.
7211................................  Traveler Accommodation...........          17,375       32,853,003           1,891       2,184,689            0.09
7212................................  RV (Recreational Vehicle) Parks             2,543        2,405,045             946         991,813            0.10
                                       and Recreational Camps.
7213................................  Rooming and Boarding Houses,                  687          741,076           1,079         930,215            0.12
                                       Dormitories, and Workers' Camps.
7223................................  Special Food Services............           7,295        8,312,585           1,139         857,031            0.13
7224................................  Drinking Places (Alcoholic                 14,383       13,061,680             908         663,521            0.14
                                       Beverages).
7225................................  Restaurants and Other Eating              157,253      276,972,590           1,761       1,144,923            0.15
                                       Places.
8111................................  Automotive Repair and Maintenance          62,789      100,273,474           1,597         798,630            0.20
8113................................  Commercial and Industrial                   8,982       14,997,313           1,670       1,261,858            0.13
                                       Machinery and Equipment (except
                                       Automotive and Electronic)
                                       Repair and Maintenance.
8114................................  Personal and Household Goods                9,417       11,449,589           1,216         455,661            0.27
                                       Repair and Maintenance.

[[Page 70981]]

 
8121................................  Personal Care Services...........          52,932       64,529,881           1,219         346,123            0.35
8122................................  Death Care Services..............           6,955       13,214,986           1,900       1,130,650            0.17
8123................................  Drycleaning and Laundry Services.          13,051       16,733,433           1,282         564,862            0.23
8129................................  Other Personal Services..........          16,792       22,209,398           1,323         509,230            0.26
8131................................  Religious Organizations..........          83,837      126,171,312           1,505         722,894            0.21
8132................................  Grantmaking and Giving Services..           7,839        8,889,289           1,134       3,473,007            0.03
8133................................  Social Advocacy Organizations....           6,903        8,993,435           1,303       1,442,084            0.09
8134................................  Civic and Social Organizations...          11,030       15,706,906           1,424         697,379            0.20
8139................................  Business, Professional, Labor,             25,710       33,664,444           1,309       1,384,987            0.09
                                       Political, and Similar
                                       Organizations.
9993................................  Local Government.................           4,846      132,114,558          27,261      17,292,921            0.16
                                                                        --------------------------------------------------------------------------------
    Total...........................  .................................       1,985,235    3,863,384,856           1,946       2,403,819            0.08
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source: OSHA.


        Table VIII.F.5--Economic Impacts on Very Small Entities Affected by the Proposed Standard With Costs Calculated Using a 2% Discount Rate
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                              Average
                                                                                              Total         annualized        Average     Costs as %  of
                NAICS                              Industry                 Entities        annualized       cost per       revenue per       revenue
                                                                                              costs           entity          entity
--------------------------------------------------------------------------------------------------------------------------------------------------------
1111................................  Oilseed and Grain Farming........          $7,184       $6,027,437            $839        $609,184            0.14
1112................................  Vegetable and Melon Farming......           1,227        3,233,900           2,636         705,291            0.37
1113................................  Fruit and Tree Nut Farming.......           3,060        4,119,361           1,346         384,931            0.35
1114................................  Greenhouse, Nursery, and                    1,545        4,149,308           2,686         513,448            0.52
                                       Floriculture Production.
1119................................  Other Crop Farming...............           5,537        6,434,964           1,162         198,860            0.58
1121................................  Cattle Ranching and Farming......          10,474       11,742,592           1,121         523,461            0.21
1122................................  Hog and Pig Farming..............             585          921,175           1,575       2,022,974            0.08
1123................................  Poultry and Egg Production.......           1,356        2,018,022           1,488       2,264,037            0.07
1124................................  Sheep and Goat Farming...........             856          968,612           1,131          59,994            1.89
1125................................  Aquaculture......................              91          239,911           2,630         875,290            0.30
1129................................  Other Animal Production..........           2,806        3,272,814           1,166          88,841            1.31
1131................................  Timber Tract Operations..........             429          403,940             942       1,293,445            0.07
1132................................  Forest Nurseries and Gathering of             144          104,419             725         679,386            0.11
                                       Forest Products.
1133................................  Logging..........................           7,530        6,292,246             836       1,170,494            0.07
1141................................  Fishing..........................           2,416        1,100,212             455         667,346            0.07
1142................................  Hunting and Trapping.............             331          292,626             885         619,029            0.14
1151................................  Support Activities for Crop                 4,102        3,213,003             783       1,530,220            0.05
                                       Production.
1152................................  Support Activities for Animal               4,531        2,962,939             654         405,439            0.16
                                       Production.
1153................................  Support Activities for Forestry..           1,534        1,037,673             676         765,904            0.09
2111................................  Oil and Gas Extraction...........           4,571        6,341,178           1,387       2,574,156            0.05
2131................................  Support Activities for Mining....           8,845       14,462,495           1,635         937,066            0.17
2211................................  Electric Power Generation,                    832        2,254,730           2,709      13,316,386            0.02
                                       Transmission and Distribution.
2212................................  Natural Gas Distribution.........             267          546,792           2,049      10,690,728            0.02
2213................................  Water, Sewage and Other Systems..           3,468        5,937,995           1,712         850,747            0.20
2361................................  Residential Building Construction         167,394       90,561,837             541       1,043,976            0.05
2362................................  Nonresidential Building                    34,810       32,498,908             934       2,948,013            0.03
                                       Construction.
2371................................  Utility System Construction......          13,929       14,564,718           1,046       1,657,874            0.06
2372................................  Land Subdivision.................           4,615        2,626,758             569       1,167,179            0.05
2373................................  Highway, Street, and Bridge                 6,251        5,486,633             878       2,619,746            0.03
                                       Construction.
2379................................  Other Heavy and Civil Engineering           3,581        3,418,173             954       1,444,677            0.07
                                       Construction.
2381................................  Foundation, Structure, and                 83,470       72,226,262             865         936,942            0.09
                                       Building Exterior Contractors.
2382................................  Building Equipment Contractors...         161,684      141,354,524             874         847,521            0.10
2383................................  Building Finishing Contractors...         108,028       74,449,281             689         653,438            0.11
2389................................  Other Specialty Trade Contractors          62,342       43,480,559             697       1,039,609            0.07
3111................................  Animal Food Manufacturing........             377          349,776             928       5,316,620            0.02
3112................................  Grain and Oilseed Milling........             130          273,983           2,115      22,940,721            0.01
3113................................  Sugar and Confectionery Product               652          541,708             831       1,163,232            0.07
                                       Manufacturing.
3114................................  Fruit and Vegetable Preserving                441          532,718           1,207       3,760,308            0.03
                                       and Specialty Food Manufacturing.
3115................................  Dairy Product Manufacturing......             337          456,581           1,353       9,285,097            0.01
3116................................  Animal Slaughtering and                       996          872,620             876       2,401,951            0.04
                                       Processing.
3117................................  Seafood Product Preparation and               129          107,828             838       3,136,053            0.03
                                       Packaging.
3118................................  Bakeries and Tortilla                       4,379        4,017,779             918         635,675            0.14
                                       Manufacturing.
3119................................  Other Food Manufacturing.........           1,111        1,075,034             968       2,724,529            0.04
3121................................  Beverage Manufacturing...........           3,429        2,263,370             660       1,398,536            0.05
3122................................  Tobacco Manufacturing............              32           42,411           1,311       6,587,893            0.02
3131................................  Fiber, Yarn, and Thread Mills....              60           75,096           1,254       2,191,371            0.06
3132................................  Fabric Mills.....................             192          233,984           1,217       3,435,732            0.04
3133................................  Textile and Fabric Finishing and              263          271,517           1,031       1,915,018            0.05
                                       Fabric Coating Mills.
3141................................  Textile Furnishings Mills........             630          573,335             910         780,741            0.12
3149................................  Other Textile Product Mills......           1,705        1,270,778             745         614,109            0.12
3151................................  Apparel Knitting Mills...........              54           66,320           1,228       1,443,320            0.09
3152................................  Cut and Sew Apparel Manufacturing           2,095        1,429,596             682         637,842            0.11

[[Page 70982]]

 
3159................................  Apparel Accessories and Other                 236          188,102             796         619,537            0.13
                                       Apparel Manufacturing.
3161................................  Leather and Hide Tanning and                   61           42,671             698       2,839,687            0.02
                                       Finishing.
3162................................  Footwear Manufacturing...........              75          123,351           1,655       2,193,374            0.08
3169................................  Other Leather and Allied Product              302          187,558             621         626,299            0.10
                                       Manufacturing.
3211................................  Sawmills and Wood Preservation...           1,006        1,185,132           1,179       1,727,380            0.07
3212................................  Veneer, Plywood, and Engineered               264          633,617           2,400       4,044,768            0.06
                                       Wood Product Manufacturing.
3219................................  Other Wood Product Manufacturing.           3,327        3,257,167             979       1,053,722            0.09
3221................................  Pulp, Paper, and Paperboard Mills              27          376,078          13,794      93,208,301            0.01
3222................................  Converted Paper Product                       559          893,086           1,597       4,579,693            0.03
                                       Manufacturing.
3231................................  Printing and Related Support               10,124        5,790,603             572         693,094            0.08
                                       Activities.
3241................................  Petroleum and Coal Products                   244          494,702           2,027      28,484,143            0.01
                                       Manufacturing.
3251................................  Basic Chemical Manufacturing.....             277          556,651           2,011      21,892,698            0.01
3252................................  Resin, Synthetic Rubber, and                  226          335,765           1,485       6,835,167            0.02
                                       Artificial and Synthetic Fibers
                                       and Filaments Manufacturing.
3253................................  Pesticide, Fertilizer, and Other              229          350,781           1,534       7,269,726            0.02
                                       Agricultural Chemical
                                       Manufacturing.
3254................................  Pharmaceutical and Medicine                   546          603,519           1,106       3,960,913            0.03
                                       Manufacturing.
3255................................  Paint, Coating, and Adhesive                  448          542,317           1,211       3,140,147            0.04
                                       Manufacturing.
3256................................  Soap, Cleaning Compound, and                  704          655,288             931       2,390,628            0.04
                                       Toilet Preparation Manufacturing.
3259................................  Other Chemical Product and                    579          723,101           1,250       3,072,599            0.04
                                       Preparation Manufacturing.
3261................................  Plastics Product Manufacturing...           2,192        2,911,100           1,328       2,782,966            0.05
3262................................  Rubber Product Manufacturing.....             382          557,177           1,459       2,487,702            0.06
3271................................  Clay Product and Refractory                   328          323,850             989       1,473,179            0.07
                                       Manufacturing.
3272................................  Glass and Glass Product                       539          546,405           1,014       1,791,588            0.06
                                       Manufacturing.
3273................................  Cement and Concrete Product                 1,336        1,655,935           1,240       2,456,404            0.05
                                       Manufacturing.
3274................................  Lime and Gypsum Product                        51          122,726           2,409       7,351,270            0.03
                                       Manufacturing.
3279................................  Other Nonmetallic Mineral Product           1,006        1,149,905           1,143       1,653,776            0.07
                                       Manufacturing.
3311................................  Iron and Steel Mills and                      103          218,406           2,121       6,567,240            0.03
                                       Ferroalloy Manufacturing.
3312................................  Steel Product Manufacturing from              121          265,350           2,191       7,339,261            0.03
                                       Purchased Steel.
3313................................  Alumina and Aluminum Production                82          262,328           3,197      12,497,676            0.03
                                       and Processing.
3314................................  Nonferrous Metal (except                      178          278,430           1,566       8,757,990            0.02
                                       Aluminum) Production and
                                       Processing.
3315................................  Foundries........................             391          547,296           1,398       2,192,210            0.06
3321................................  Forging and Stamping.............             556          557,664           1,003       2,020,339            0.05
3322................................  Cutlery and Handtool                          373          259,248             695       1,107,327            0.06
                                       Manufacturing.
3323................................  Architectural and Structural                4,125        4,085,887             991       1,456,833            0.07
                                       Metals Manufacturing.
3324................................  Boiler, Tank, and Shipping                    300          423,339           1,409       3,917,337            0.04
                                       Container Manufacturing.
3325................................  Hardware Manufacturing...........             186          153,954             828       1,511,537            0.05
3326................................  Spring and Wire Product                       298          292,858             983       1,589,842            0.06
                                       Manufacturing.
3327................................  Machine Shops; Turned Product;              8,812        6,785,989             770         910,823            0.08
                                       and Screw, Nut, and Bolt
                                       Manufacturing.
3328................................  Coating, Engraving, Heat                    1,740        1,753,611           1,008         985,271            0.10
                                       Treating, and Allied Activities.
3329................................  Other Fabricated Metal Product              1,998        2,026,136           1,014       1,910,855            0.05
                                       Manufacturing.
3331................................  Agriculture, Construction, and                776          880,986           1,135       2,303,225            0.05
                                       Mining Machinery Manufacturing.
3332................................  Industrial Machinery                          951          827,287             870       1,790,885            0.05
                                       Manufacturing.
3333................................  Commercial and Service Industry               602          467,902             777       1,741,883            0.04
                                       Machinery Manufacturing.
3334................................  Ventilation, Heating, Air-                    409          485,787           1,186       2,390,594            0.05
                                       Conditioning, and Commercial
                                       Refrigeration Equipment
                                       Manufacturing.
3335................................  Metalworking Machinery                      2,174        1,503,816             692       1,172,111            0.06
                                       Manufacturing.
3336................................  Engine, Turbine, and Power                    186          279,911           1,504       4,514,698            0.03
                                       Transmission Equipment
                                       Manufacturing.
3339................................  Other General Purpose Machinery             1,576        1,782,884           1,131       2,828,012            0.04
                                       Manufacturing.
3341................................  Computer and Peripheral Equipment             317          181,009             570       2,040,422            0.03
                                       Manufacturing.
3342................................  Communications Equipment                      374          275,245             735       2,213,015            0.03
                                       Manufacturing.
3343................................  Audio and Video Equipment                     180           98,831             548       1,509,740            0.04
                                       Manufacturing.
3344................................  Semiconductor and Other                       991          740,401             747       1,810,399            0.04
                                       Electronic Component
                                       Manufacturing.
3345................................  Navigational, Measuring,                    1,411          961,637             682       2,280,952            0.03
                                       Electromedical, and Control
                                       Instruments Manufacturing.
3346................................  Manufacturing and Reproducing                 158           80,247             509         869,333            0.06
                                       Magnetic and Optical Media.
3351................................  Electric Lighting Equipment                   321          290,904             906       2,228,223            0.04
                                       Manufacturing.
3352................................  Household Appliance Manufacturing              73           67,216             915       1,907,392            0.05
3353................................  Electrical Equipment                          543          585,477           1,078       2,265,967            0.05
                                       Manufacturing.
3359................................  Other Electrical Equipment and                530          775,438           1,462       4,923,782            0.03
                                       Component Manufacturing.
3361................................  Motor Vehicle Manufacturing......              72           42,019             586       8,079,095            0.01
3362................................  Motor Vehicle Body and Trailer                462          571,401           1,237       2,128,388            0.06
                                       Manufacturing.
3363................................  Motor Vehicle Parts Manufacturing           1,140        1,248,555           1,096       2,450,442            0.04
3364................................  Aerospace Product and Parts                   368          569,759           1,550       4,750,992            0.03
                                       Manufacturing.
3365................................  Railroad Rolling Stock                         32          104,712           3,303      12,137,746            0.03
                                       Manufacturing.
3366................................  Ship and Boat Building...........             446          605,519           1,357       1,347,324            0.10
3369................................  Other Transportation Equipment                321          258,348             804       1,487,253            0.05
                                       Manufacturing.
3371................................  Household and Institutional                 4,244        3,437,887             810         718,130            0.11
                                       Furniture and Kitchen Cabinet
                                       Manufacturing.

[[Page 70983]]

 
3372................................  Office Furniture (including                 1,162        1,046,524             901       1,149,394            0.08
                                       Fixtures) Manufacturing.
3379................................  Other Furniture Related Product               216          288,388           1,337       2,340,433            0.06
                                       Manufacturing.
3391................................  Medical Equipment and Supplies              3,950        2,735,349             693         758,887            0.09
                                       Manufacturing.
3399................................  Other Miscellaneous Manufacturing           7,399        5,215,239             705         801,390            0.09
4231................................  Motor Vehicle and Motor Vehicle             1,257        4,993,354           3,973       3,303,747            0.12
                                       Parts and Supplies Merchant
                                       Wholesalers.
4232................................  Furniture and Home Furnishing                 910        3,110,498           3,417       2,854,446            0.12
                                       Merchant Wholesalers.
4233................................  Lumber and Other Construction                 785        2,505,110           3,193       3,557,039            0.09
                                       Materials Merchant Wholesalers.
4234................................  Professional and Commercial                 1,916        5,577,568           2,912       2,405,983            0.12
                                       Equipment and Supplies Merchant
                                       Wholesalers.
4235................................  Metal and Mineral (except                     556        2,106,984           3,790       6,228,340            0.06
                                       Petroleum) Merchant Wholesalers.
4236................................  Household Appliances and                    1,576        5,580,492           3,542       3,369,434            0.11
                                       Electrical and Electronic Goods
                                       Merchant Wholesalers.
4237................................  Hardware, and Plumbing and                    816        2,636,524           3,230       2,796,763            0.12
                                       Heating Equipment and Supplies
                                       Merchant Wholesalers.
4238................................  Machinery, Equipment, and                   3,312       15,267,247           4,610       2,896,468            0.16
                                       Supplies Merchant Wholesalers.
4239................................  Miscellaneous Durable Goods                 2,551        6,358,104           2,492       2,832,277            0.09
                                       Merchant Wholesalers.
4241................................  Paper and Paper Product Merchant              610        2,004,758           3,287       2,995,604            0.11
                                       Wholesalers.
4242................................  Drugs and Druggists' Sundries                 563        1,888,913           3,356       4,020,123            0.08
                                       Merchant Wholesalers.
4243................................  Apparel, Piece Goods, and Notions           1,248        3,098,845           2,483       2,808,295            0.09
                                       Merchant Wholesalers.
4244................................  Grocery and Related Product                 2,242        7,359,247           3,283       4,893,717            0.07
                                       Merchant Wholesalers.
4245................................  Farm Product Raw Material                     266        1,240,969           4,671      11,316,686            0.04
                                       Merchant Wholesalers.
4246................................  Chemical and Allied Products                  676        2,375,082           3,516       5,030,093            0.07
                                       Merchant Wholesalers.
4247................................  Petroleum and Petroleum Products              263        1,242,062           4,718      20,772,751            0.02
                                       Merchant Wholesalers.
4248................................  Beer, Wine, and Distilled                     243          763,626           3,147       3,176,806            0.10
                                       Alcoholic Beverage Merchant
                                       Wholesalers.
4249................................  Miscellaneous Nondurable Goods              1,870        6,010,140           3,215       2,900,974            0.11
                                       Merchant Wholesalers.
4251................................  Wholesale Trade Agents and                  3,577        7,395,194           2,068       8,758,811            0.02
                                       Brokers.
4411................................  Automobile Dealers...............           4,702        9,420,631           2,004       3,255,236            0.06
4412................................  Other Motor Vehicle Dealers......           1,853        4,518,777           2,439       2,697,277            0.09
4413................................  Automotive Parts, Accessories,              4,859       11,159,040           2,297       1,134,410            0.20
                                       and Tire Retailers.
4441................................  Building Material and Supplies              5,693        7,059,545           1,240       1,614,974            0.08
                                       Dealers.
4442................................  Lawn and Garden Equipment and               2,502        5,016,485           2,005       1,498,082            0.13
                                       Supplies Retailers.
4451................................  Grocery and Convenience Retailers          10,521       16,794,972           1,596       1,054,320            0.15
4452................................  Specialty Food Retailers.........           3,551        5,729,397           1,613         900,891            0.18
4453................................  Beer, Wine, and Liquor Retailers.           5,163        5,975,343           1,157       1,325,671            0.09
4491................................  Furniture and Home Furnishings              6,010        8,962,736           1,491       1,223,523            0.12
                                       Retailers.
4492................................  Electronics and Appliance                   3,217        4,908,069           1,525       1,030,417            0.15
                                       Retailers.
4551................................  Department Stores................             148          190,770           1,287       1,621,586            0.08
4552................................  Warehouse Clubs, Supercenters,              2,556        3,419,681           1,338         842,471            0.16
                                       and Other General Merchandise
                                       Retailers.
4561................................  Health and Personal Care                    7,776        9,533,570           1,226       1,791,759            0.07
                                       Retailers.
4571................................  Gasoline Stations................          10,327       15,498,593           1,501       2,804,858            0.05
4572................................  Fuel Dealers.....................             649        1,060,755           1,635       2,693,189            0.06
4581................................  Clothing and Clothing Accessories           5,967        8,712,135           1,460         698,207            0.21
                                       Retailers.
4582................................  Shoe Retailers...................           1,010        1,421,801           1,408       1,020,151            0.14
4583................................  Jewelry, Luggage, and Leather               2,976        3,898,966           1,310       1,079,268            0.12
                                       Goods Retailers.
4591................................  Sporting Goods, Hobby, and                  5,150        7,074,290           1,374         864,136            0.16
                                       Musical Instrument Retailers.
4592................................  Book Retailers and News Dealers..             774          988,633           1,278         744,295            0.17
4593................................  Florists.........................           2,213        3,540,277           1,600         494,498            0.32
4594................................  Office Supplies, Stationery, and            3,317        4,621,207           1,393         627,443            0.22
                                       Gift Retailers.
4595................................  Used Merchandise Retailers.......           2,352        3,240,613           1,378         608,402            0.23
4599................................  Other Miscellaneous Retailers....           5,911        8,732,908           1,477       1,042,423            0.14
4811................................  Scheduled Air Transportation.....             278          293,355           1,054       3,080,504            0.03
4812................................  Nonscheduled Air Transportation..           1,285        1,286,819           1,001       2,040,509            0.05
4821................................  Rail Transportation..............              96           51,361             536         399,619            0.13
4831................................  Deep Sea, Coastal, and Great                  455          544,184           1,196       2,200,414            0.05
                                       Lakes Water Transportation.
4832................................  Inland Water Transportation......             323          453,643           1,403       1,350,810            0.10
4841................................  General Freight Trucking.........          51,643       37,499,799             726         861,013            0.08
4842................................  Specialized Freight Trucking.....          35,020       26,650,522             761         892,912            0.09
4851................................  Urban Transit Systems............             373          312,637             839         839,880            0.10
4852................................  Interurban and Rural Bus                      332          422,567           1,274         833,268            0.15
                                       Transportation.
4853................................  Taxi and Limousine Service.......           5,931        6,596,898           1,112         473,725            0.23
4854................................  School and Employee Bus                     1,444        1,578,496           1,093         381,438            0.29
                                       Transportation.
4855................................  Charter Bus Industry.............             663          764,143           1,152         976,121            0.12
4859................................  Other Transit and Ground                    3,097        2,381,262             769         514,988            0.15
                                       Passenger Transportation.
4861................................  Pipeline Transportation of Crude               27           34,499           1,282       5,687,521            0.02
                                       Oil.
4862................................  Pipeline Transportation of                     59           90,847           1,528      15,269,599            0.01
                                       Natural Gas.
4869................................  Other Pipeline Transportation....              29           37,586           1,288       4,867,763            0.03
4871................................  Scenic and Sightseeing                        474          570,363           1,203         670,486            0.18
                                       Transportation, Land.
4872................................  Scenic and Sightseeing                      1,385        2,109,958           1,524         589,761            0.26
                                       Transportation, Water.
4879................................  Scenic and Sightseeing                        208          272,900           1,311         812,572            0.16
                                       Transportation, Other.
4881................................  Support Activities for Air                  2,961        3,481,748           1,176       1,058,641            0.11
                                       Transportation.

[[Page 70984]]

 
4882................................  Support Activities for Rail                   315          430,553           1,366       1,603,240            0.09
                                       Transportation.
4883................................  Support Activities for Water                1,396        1,914,888           1,372       1,256,551            0.11
                                       Transportation.
4884................................  Support Activities for Road                 8,222        6,121,945             745         687,092            0.11
                                       Transportation.
4885................................  Freight Transportation                     11,283       15,674,157           1,389       1,583,872            0.09
                                       Arrangement.
4889................................  Other Support Activities for                1,202        1,095,829             912         799,155            0.11
                                       Transportation.
4921................................  Couriers and Express Delivery               3,125        2,811,195             900         843,986            0.11
                                       Services.
4922................................  Local Messengers and Local                  2,990        2,455,403             821         741,162            0.11
                                       Delivery.
4931................................  Warehousing and Storage..........           3,555        3,599,514           1,012       1,301,304            0.08
5121................................  Motion Picture and Video                    2,383        4,673,631           1,962         903,851            0.22
                                       Industries.
5122................................  Sound Recording Industries.......             445          780,716           1,754         660,025            0.27
5131................................  Newspaper, Periodical, Book, and            1,936        4,503,697           2,326         816,692            0.28
                                       Directory Publishers.
5132................................  Software Publishers..............           1,057        2,023,518           1,915       1,268,517            0.15
5161................................  Radio and Television Broadcasting             370        1,470,235           3,969         662,207            0.60
                                       Stations.
5162................................  Media Streaming Distribution                  235          560,991           2,388       1,346,479            0.18
                                       Services, Social Networks, and
                                       Other Media Networks and Content
                                       Providers.
5171................................  Wired and Wireless                            942        1,900,994           2,018       1,249,302            0.16
                                       Telecommunications (except
                                       Satellite).
5174................................  Satellite Telecommunications.....              40           86,847           2,157       1,745,466            0.12
5178................................  All Other Telecommunications.....             287          502,736           1,753       1,126,736            0.16
5182................................  Computing Infrastructure                    1,112        2,196,650           1,976       1,171,961            0.17
                                       Providers, Data Processing, Web
                                       Hosting, and Related Services.
5192................................  Web Search Portals, Libraries,                468          867,704           1,853         507,510            0.37
                                       Archives, and Other Information
                                       Services.
5221................................  Depository Credit Intermediation.             637        1,709,643           2,682       1,711,700            0.16
5222................................  Nondepository Credit                        1,654        3,919,691           2,369       1,191,143            0.20
                                       Intermediation.
5223................................  Activities Related to Credit                1,718        3,212,716           1,870         758,941            0.25
                                       Intermediation.
5231................................  Securities and Commodity                    1,349        2,298,865           1,704       1,235,568            0.14
                                       Contracts Intermediation and
                                       Brokerage.
5232................................  Securities and Commodity                        0           19,633          39,745     753,808,884            0.01
                                       Exchanges.
5239................................  Other Financial Investment                  6,852       11,878,438           1,734       1,247,480            0.14
                                       Activities.
5241................................  Insurance Carriers...............             499        1,011,256           2,025       3,600,269            0.06
5242................................  Agencies, Brokerages, and Other            17,366       34,184,872           1,968         575,155            0.34
                                       Insurance Related Activities.
5251................................  Insurance and Employee Benefit                197          166,858             849         198,788            0.43
                                       Funds.
5259................................  Other Investment Pools and Funds.             112          200,679           1,786       1,085,641            0.16
5311................................  Lessors of Real Estate...........          12,961       26,616,095           2,054       1,090,656            0.19
5312................................  Offices of Real Estate Agents and          14,379       25,261,103           1,757         700,221            0.25
                                       Brokers.
5313................................  Activities Related to Real Estate          10,077       22,407,861           2,224         584,901            0.38
5321................................  Automotive Equipment Rental and               482        1,447,641           3,004       1,018,247            0.29
                                       Leasing.
5322................................  Consumer Goods Rental............           1,039        3,003,692           2,891         609,218            0.47
5323................................  General Rental Centers...........             284          865,973           3,049         969,539            0.31
5324................................  Commercial and Industrial                     949        2,282,588           2,404       1,447,107            0.17
                                       Machinery and Equipment Rental
                                       and Leasing.
5331................................  Lessors of Nonfinancial                       285          476,238           1,669       3,054,162            0.05
                                       Intangible Assets (except
                                       Copyrighted Works).
5411................................  Legal Services...................          22,852       45,807,442           2,005         747,237            0.27
5412................................  Accounting, Tax Preparation,               14,754       29,735,652           2,015         425,212            0.47
                                       Bookkeeping, and Payroll
                                       Services.
5413................................  Architectural, Engineering, and            11,568       42,680,149           3,690         796,165            0.46
                                       Related Services.
5414................................  Specialized Design Services......           4,322       10,844,535           2,509         651,156            0.39
5415................................  Computer Systems Design and                15,074       30,869,789           2,048         699,158            0.29
                                       Related Services.
5416................................  Management, Scientific, and                21,484       48,439,074           2,255         605,529            0.37
                                       Technical Consulting Services.
5417................................  Scientific Research and                     1,662        4,503,806           2,709       1,184,901            0.23
                                       Development Services.
5418................................  Advertising, Public Relations,              4,240       11,597,282           2,735         972,915            0.28
                                       and Related Services.
5419................................  Other Professional, Scientific,             8,042       31,055,715           3,862         718,191            0.54
                                       and Technical Services.
5511................................  Management of Companies and                   622        1,694,619           2,724       2,000,475            0.14
                                       Enterprises.
5611................................  Office Administrative Services...           3,518        5,423,804           1,542         785,494            0.20
5612................................  Facilities Support Services......             157          441,128           2,817       1,344,810            0.21
5613................................  Employment Services..............           2,522        4,435,122           1,758         862,254            0.20
5614................................  Business Support Services........           2,939        3,932,901           1,338         637,724            0.21
5615................................  Travel Arrangement and                      1,846        2,452,247           1,328       1,145,290            0.12
                                       Reservation Services.
5616................................  Investigation and Security                  2,305        7,402,537           3,212         568,222            0.57
                                       Services.
5617................................  Services to Buildings and                  24,202       62,022,534           2,563         441,221            0.58
                                       Dwellings.
5619................................  Other Support Services...........           2,194        4,403,819           2,007         960,942            0.21
5621................................  Waste Collection.................             893        1,162,660           1,301       1,262,504            0.10
5622................................  Waste Treatment and Disposal.....             140          316,092           2,251       1,725,940            0.13
5629................................  Remediation and Other Waste                 1,086        3,133,580           2,885       1,098,195            0.26
                                       Management Services.
6111................................  Elementary and Secondary Schools.           1,169        3,475,761           2,973         637,302            0.47
6112................................  Junior Colleges..................              29          111,992           3,817       2,336,262            0.16
6113................................  Colleges, Universities, and                   119          231,971           1,952       1,512,355            0.13
                                       Professional Schools.
6114................................  Business Schools and Computer and           1,062        1,591,435           1,498         755,854            0.20
                                       Management Training.
6115................................  Technical and Trade Schools......             841        1,646,426           1,959         687,422            0.28
6116................................  Other Schools and Instruction....           6,476       11,488,813           1,774         332,175            0.53
6117................................  Educational Support Services.....           1,096        1,574,151           1,437         604,768            0.24
6211................................  Offices of Physicians............           6,908       12,269,746           1,776         960,870            0.18
6212................................  Offices of Dentists..............           5,290       13,513,854           2,555         948,924            0.27

[[Page 70985]]

 
6213................................  Offices of Other Health                     5,695       10,110,019           1,775         447,256            0.40
                                       Practitioners.
6214................................  Outpatient Care Centers..........             536        1,544,461           2,879         989,325            0.29
6215................................  Medical and Diagnostic                        265          717,035           2,703       1,182,302            0.23
                                       Laboratories.
6216................................  Home Health Care Services........             653        2,917,046           4,468         518,702            0.86
6219................................  Other Ambulatory Health Care                  209          655,184           3,137         797,038            0.39
                                       Services.
6221................................  General Medical and Surgical                    4           20,164           5,297      10,704,238            0.05
                                       Hospitals.
6222................................  Psychiatric and Substance Abuse                 1           60,072          40,967      15,140,669            0.27
                                       Hospitals.
6223................................  Specialty (except Psychiatric and               2           89,129          45,058      23,112,360            0.19
                                       Substance Abuse) Hospitals.
6231................................  Nursing Care Facilities (Skilled               97          299,181           3,092       1,138,055            0.27
                                       Nursing Facilities).
6232................................  Residential Intellectual and                  246        1,184,615           4,820         495,389            0.97
                                       Developmental Disability, Mental
                                       Health, and Substance Abuse
                                       Facilities.
6233................................  Continuing Care Retirement                    523        2,224,552           4,252         439,078            0.97
                                       Communities and Assisted Living
                                       Facilities for the Elderly.
6239................................  Other Residential Care Facilities              83          513,007           6,216         469,247            1.32
6241................................  Individual and Family Services...           1,805        7,386,994           4,092         424,361            0.96
6242................................  Community Food and Housing, and               334        1,555,480           4,659         990,632            0.47
                                       Emergency and Other Relief
                                       Services.
6243................................  Vocational Rehabilitation                      81          345,131           4,262         566,673            0.75
                                       Services.
6244................................  Child Care Services..............           2,132       20,144,880           9,448         290,434            3.25
7111................................  Performing Arts Companies........           4,171        4,129,821             990         787,860            0.13
7112................................  Spectator Sports.................           1,794        1,430,879             797       1,258,295            0.06
7113................................  Promoters of Performing Arts,               3,604        3,665,186           1,017       1,122,492            0.09
                                       Sports, and Similar Events.
7114................................  Agents and Managers for Artists,            2,047        2,033,576             993       1,093,566            0.09
                                       Athletes, Entertainers, and
                                       Other Public Figures.
7115................................  Independent Artists, Writers, and          15,202       14,251,524             937         787,943            0.12
                                       Performers.
7121................................  Museums, Historical Sites, and              3,149        3,311,160           1,051         608,424            0.17
                                       Similar Institutions.
7131................................  Amusement Parks and Arcades......           1,354        1,316,414             972         516,918            0.19
7132................................  Gambling Industries..............             744          922,020           1,239       1,354,532            0.09
7139................................  Other Amusement and Recreation             28,297       22,821,999             807         483,584            0.17
                                       Industries.
7211................................  Traveler Accommodation...........          12,993       15,574,139           1,199         877,297            0.14
7212................................  RV (Recreational Vehicle) Parks             2,293        1,620,981             707         721,900            0.10
                                       and Recreational Camps.
7213................................  Rooming and Boarding Houses,                  654          651,616             996         650,782            0.15
                                       Dormitories, and Workers' Camps.
7223................................  Special Food Services............           6,293        4,826,527             767         453,753            0.17
7224................................  Drinking Places (Alcoholic                 12,801        9,231,321             721         450,393            0.16
                                       Beverages).
7225................................  Restaurants and Other Eating              117,267      109,738,307             936         537,890            0.17
                                       Places.
8111................................  Automotive Repair and Maintenance          64,015       85,582,777           1,337         646,006            0.21
8112................................  Electronic and Precision                    4,843        7,081,340           1,462         555,490            0.26
                                       Equipment Repair and Maintenance.
8113................................  Commercial and Industrial                   8,375       11,158,572           1,332         842,857            0.16
                                       Machinery and Equipment (except
                                       Automotive and Electronic)
                                       Repair and Maintenance.
8114................................  Personal and Household Goods                9,205       10,159,719           1,104         380,439            0.29
                                       Repair and Maintenance.
8121................................  Personal Care Services...........          50,363       59,103,771           1,174         267,441            0.44
8122................................  Death Care Services..............           6,418        9,445,610           1,472         854,725            0.17
8123................................  Drycleaning and Laundry Services.          12,190       12,520,561           1,027         353,835            0.29
8129................................  Other Personal Services..........          15,818       15,920,372           1,006         339,338            0.30
8131................................  Religious Organizations..........          76,718       98,017,873           1,278         417,227            0.31
8132................................  Grantmaking and Giving Services..           7,573        8,483,782           1,120       2,705,446            0.04
8133................................  Social Advocacy Organizations....           6,199        6,958,994           1,123         816,788            0.14
8134................................  Civic and Social Organizations...          10,249       12,512,391           1,221         479,271            0.25
8139................................  Business, Professional, Labor,             23,841       28,061,383           1,177         819,457            0.14
                                       Political, and Similar
                                       Organizations.
9993................................  Local Government.................           1,922        4,052,837           2,109       1,111,959            0.19
                                                                        --------------------------------------------------------------------------------
    Total...........................  .................................       1,847,745    2,177,399,776           1,178         987,455            0.12
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source: OSHA.

F. Federal Rules Which May Duplicate, Overlap, or Conflict With the 
Proposed Rule
    The Regulatory Flexibility Act (RFA) requires that the agency's 
initial regulatory flexibility Analysis identify, ``to the extent 
practicable, . . . all relevant Federal rules which may duplicate, 
overlap or conflict with the proposed rule'' (5 U.S.C. 603(b)(5)). 
Below, OSHA discusses whether the rules it has identified would 
duplicate, overlap, or conflict with the options for a potential 
standard as outlined above. While some Federal rules may have 
overlapping requirements, OSHA did not identify any rules that would 
conflict with the proposed standard. The agency therefore believes that 
no Federal rules would prevent compliance with the proposed standard.
I. Other Federal Agency Rules
    The first Federal rules that OSHA identified are regulations 
promulgated by the Environmental Protection Agency (EPA) under the 
Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) (7 U.S.C. 
136 et seq.). The Worker Protection Standard (WPS) (40 CFR part 170) is 
designed to protect agricultural workers from ``unreasonable adverse 
effects of pesticides'' (80 FR 67496); however, there are some 
provisions of the WPS addressing heat hazards associated with PPE use 
required by that standard. The WPS requires that employers implement 
``appropriate'' or

[[Page 70986]]

``sufficient'' measures to prevent heat-related illness when workers 
must wear PPE (40 CFR 170.507, 170.605). The WPS also requires 
employers to ensure pesticide handlers are trained on how to recognize, 
prevent, and provide first aid treatment for heat-related illnesses (40 
CFR 170.501). Although there may be some overlap between these 
requirements and some elements of the proposed standard (e.g., 
training), OSHA is not aware of any conflicts. OSHA's proposed standard 
would be entirely consistent with EPA's requirements around PPE 
considerations and training for pesticide handlers. Additionally, the 
WPS, designed to protect workers from pesticide exposure, does not 
obviate the need for OSHA's proposed standard, designed to protect 
workers from hazardous heat. A multitude of factors, including PPE, can 
contribute to heat injury and illness.
    The second set of Federal rules that OSHA identified are Department 
of Transportation (DOT) regulations. The Federal Motor Carrier Safety 
Administration (FMCSA) requires drivers of vehicles with gross vehicle 
weight ratings of 26,001 pounds or more to be instructed about extreme 
driving conditions, including high heat, to obtain commercial driver's 
licenses (49 CFR part 380). FMCSA's regulations might overlap with 
OSHA's proposed rule to the extent they require some training for a 
limited group of individuals. However, these regulations would not 
conflict with OSHA's proposed rule, nor do they obviate the need for a 
comprehensive OSHA standard with provisions specifically designed to 
protect workers exposed to a broad range of hazardous heat conditions.
II. OSHA Standards
    OSHA does not have any standards that specifically address 
workplace exposure to hazardous heat. However, OSHA has identified some 
current standards applicable to some issues related to hazardous heat. 
These standards, described below, do not conflict with the proposed 
rule, nor do they obviate the need for an OSHA standard addressing 
occupational exposure to hazardous heat.
    The first set of standards OSHA identified are the sanitation 
standards (29 CFR 1910.141, 1926.51, 1915.88, 1917.127, 1918.95, 
1928.110). Among other things, these standards require employers to 
provide employees with readily accessible potable drinking water and 
access to toilet facilities. The field sanitation standard for 
agriculture also requires employers to notify employees of the location 
of water and the importance of drinking water frequently, especially on 
hot days (29 CFR 1928.110(c)(4)). These existing standards and the 
provisions of the proposed rule do not conflict, nor do these existing 
standards obviate the need for a heat-specific standard. While OSHA's 
sanitation standards require employers to make drinking water available 
to employees, their primary purpose is to ensure sanitary conditions in 
the workplace and they do not include the same level of specificity for 
provision of water as the proposed standard (e.g., specific quantity of 
water to be provided).
    The second set of standards OSHA has identified are specific to 
pulp and paper and textile mills. These standards require that exposed 
water pipes that carry either steam or hot water and are located close 
to working platforms be guarded to prevent contact (29 CFR 
1910.261(k)(11), 1910.262). These standards are primarily concerned 
with burn and scalding-related hazards to employees. However, when 
employers guard these pipes by using insulating material, they may also 
help protect their workplace from increases in temperatures that may, 
in some cases, induce HRIs. Thus, the existing standards and the 
proposed standard would be complementary in nature.
    The third set of standards that OSHA has identified are two broadly 
applicable standards that may apply to some heat-related hazards--the 
Recordkeeping standard (29 CFR 1904.7) and the Safety Training and 
Education standard for construction (29 CFR 1926.21). OSHA's 
Recordkeeping standard requires employers to record and report injuries 
and illnesses, including heat-related injuries and illnesses, that meet 
recording criteria. This proposed standard does not include additional 
requirements for recording and reporting injuries and illnesses and 
therefore does not duplicate or conflict with 29 CFR 1904.7. OSHA's 
Safety Training and Education standard requires employers in the 
construction industry to train employees in the recognition, avoidance, 
and prevention of unsafe conditions in their workplaces. However, the 
standard does not specifically identify hazardous heat as a hazard for 
which workers need training, nor does it establish heat-specific 
training requirements.
    These standards might, in some cases, overlap with some of the 
provisions of the proposed standard. However, they do not duplicate or 
conflict with the proposed standard. OSHA believes that a comprehensive 
standard addressing HRIs is necessary to ensure that all employers take 
all appropriate measures to protect workers from the hazards associated 
with exposure to hazardous heat. If specific requirements of any final 
heat standard were to directly overlap with more general requirements 
in other existing standards, the specific requirements would apply in 
lieu of the more general requirements, unless otherwise noted (see 29 
CFR 1910.5(c)(1)); see also the discussion of the continued 
applicability of the sanitation standards in the Explanation of 
Proposed Requirements for paragraph (e)(2), Drinking Water).
G. Alternatives and Regulatory Options to the Proposed Rule
    This section presents regulatory alternatives and options to the 
proposed OSHA Heat Injury and Illness Prevention standard and OSHA's 
responses to the findings and recommendations of the SBAR panel.
    Under the RFA, a regulatory alternative is one that would 
accomplish the stated objectives of the proposed standard and that 
would minimize or reduce economic impact of the proposed rule on small 
entities. A regulatory alternative can reduce the impact on businesses 
of all sizes, and it need not focus solely on small entities. OSHA also 
presents regulatory options. Regulatory options would increase the 
burden of compliance on affected entities and therefore do not meet the 
definition of a regulatory alternative set out in the RFA. 
Nevertheless, the agency presents them in this section to provide 
notice of potential alternate approaches and to solicit comment on 
these options. Table VIII.F.1. presents these options and alternatives. 
The assumptions and parameters for estimating the impact of these 
options and alternatives is discussed below the table.
    OMB Circular A-4 (2023) directs agencies, for purposes of complying 
with E.O. 12866, to identify key attributes or provisions of a proposed 
standard and examine options for each ``including: the proposed or 
finalized option; at least one option that achieves additional benefits 
(and presumably costs more due to, for example, greater stringency); 
and at least one option that costs less (and presumably generates fewer 
benefits due to, for example, less stringency).'' For this proposed 
standard, OSHA identified requirements for rest breaks and for written 
HIIPPs as the key provisions for purposes of its E.O. 12866 analysis. 
The requirements of the proposed standard work in concert to produce 
the benefit of avoided HRIs and fatalities. The agency is unable to 
directly attribute avoided

[[Page 70987]]

HRIs and fatalities to any specific provision so is unable to discuss 
the differences in the benefits of alternatives other than based on the 
assumption that more stringent options might increase benefits while 
less stringent alternatives might decrease benefits.
    As shown in table VIII.F.6. an option to require high heat 
triggered rest breaks every hour, is the costliest, incurring an 
additional $23.0 billion annually compared to the proposed requirement 
of rest breaks every two hours. The alternative that would reduce the 
compliance costs the most would be one that required 10-minute high 
heat triggered rest breaks (versus the 15-minute rest breaks required 
in the proposed standard), which results in approximately $3.2 billion 
less in compliance costs per year.

                                              Table VIII.F.6--Costs for Regulatory Options and Alternatives
                                                                         [2023$]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                       In-scope         In-scope        In-scope     Annualized costs
                            Description                                entities      establishments     employees           (2%)           Difference
--------------------------------------------------------------------------------------------------------------------------------------------------------
Proposed standard as written......................................       2,230,750        2,535,774      35,954,325    $7,823,661,638                 $0
Review HIIPP at least every other year instead of at least               2,230,750        2,535,774      35,954,325     7,737,630,422        -86,031,216
 annually.........................................................
No written HIIPP required for <20 employees instead of <10               2,230,750        2,535,774      35,954,325     7,821,535,276         -2,126,362
 employees........................................................
All establishments write HIIPP regardless of number of employees..       2,230,750        2,535,774      35,954,325     7,839,027,706         15,366,068
At or above the high heat trigger, 15-minute rest break at least         2,230,750        2,535,774      35,954,325    30,821,032,888     22,997,371,249
 every hour instead of at least every two hours...................
At or above the high heat trigger, 10-minute rest break at least         2,230,750        2,535,774      35,954,325     4,601,335,411     -3,222,326,227
 every two hours instead of 15-minute rest break at least every
 two hours........................................................
Refresher trainings at least every other year instead of annually.       2,230,750        2,535,774      35,954,325     7,585,132,580       -238,529,059
High heat trigger of 95[deg] heat index instead of 90[deg] heat          2,230,750        2,535,774      35,954,325     5,967,548,421     -1,856,113,217
 index............................................................
Acclimatization for employees returning after 30 days away from          2,230,750        2,535,774      35,954,325     7,822,809,795           -851,843
 work, instead of after 14 days away from work....................
Limit the sedentary work exemption to sedentary work activities at       2,230,750        2,535,774      35,954,325     7,824,928,699          1,267,060
 indoor work areas below [a heat index of 90 [deg]F]..............
Add a requirement for employers to provide medical surveillance...       2,230,750        2,535,774      35,954,325    10,301,080,493      2,477,418,855
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source: OSHA.

I. Regulatory Options
a. Regulatory Option 1--All Establishments Write HIIPPs Regardless of 
Number of Employees
    This alternative assumes that all establishments have their HIIPP 
in writing compared to the proposed standard where establishments with 
ten or fewer employees do not need to have their HIIPP in writing. All 
establishments with ten or fewer employees that do not have an existing 
HIIPP in place are modeled as either using OSHA's template (six hours 
of a designated person's labor time) or writing their HIIPP from 
scratch (30 hours) in the same proportions that were assumed for 
establishments of other sizes.
    This regulatory option would add about $15.4 million in additional 
costs. OSHA believes that having a written plan is an important tool in 
protecting employees from heat and other workplace hazards. However, 
experience has shown that for the smallest employers, employees and 
supervisors or owners are working closely enough together that the 
details of safety plans can be readily communicated between 
individuals. The agency believes that written plans are not necessary 
for employers with 10 or fewer employees and that this is a useful way 
to reduce the burden on the smallest employers (although they would 
still need to have a HIIPP as required by this proposed standard).
b. Regulatory Option 2--At or Above the High Heat Trigger 15-Minute 
Rest Break at Least Every Hour
    The proposed standard would require employers to provide a 15-
minute rest break at least every two hours when the high heat trigger 
is met. This option would require employers to instead provide a 15-
minute rest break to their at-risk employees at least every hour where 
the high heat trigger is met. As such, the cost for rest breaks would 
be incurred six times during an 8-hour work shift where the high heat 
trigger is met (excluding rest breaks before lunch and at the end of 
the workday).
    This option would add considerable costs to this proposed 
standard--nearly $23.0 billion. As discussed throughout this preamble, 
OSHA believes that rest breaks are a crucial tool to protect employees 
from heat injury and illness. As discussed in Section VII.F., Paragraph 
(f) Requirements at or above the High Heat Trigger, at the high heat 
trigger, evidence supports providing 15-minute rest breaks where 
employees are provided with shade, water, and a chance to shed PPE in 
order to reduce their body temperature every two hours.
c. Regulatory Option 3--Upper Bound Heat Index for Sedentary Work 
Exemption
    When calculating the costs of requirements under the high heat 
trigger, this alternative leaves in-scope those employees who are 
considered sedentary but who work in non-climate-controlled indoor work 
conditions where temperatures are reasonably expected to meet or exceed 
the high heat trigger (i.e., a heat index of 90 [deg]F). This scope 
change results in more employees qualifying for high heat trigger rest 
breaks and requiring more observation time from designated persons. 
This option is estimated to increase the costs of the proposed standard 
by about $1.27 million.
d. Regulatory Option 4--Medical Surveillance
    Under the medical surveillance alternative, OSHA adds a requirement 
that all at-risk employees receive and complete a medical screening 
questionnaire to determine whether an employee may be predisposed to 
heat-related health risks. This questionnaire is assumed to take 15 
minutes. All at-risk employees are assumed to take this questionnaire 
in the first year. Only new employees (as determined by using the 
annual hire rates for each sector) are modeled to take this 
questionnaire in subsequent years.
    OSHA also assumes that employees screened as having a 
predisposition to heat-related health risks (assumed to be 23 percent 
of all at-risk employees) undergo a medical examination. This medical 
examination would take one hour of an at-risk worker's labor time. The 
cost of the medical examination itself, which the employer would need 
to cover at no cost to the employee, is estimated to cost $501.28.
    Based on these assumptions, this option would increase the costs of 
the proposed standard by about $2.5 billion.

[[Page 70988]]

The proposed standard currently includes a suite of controls that OSHA 
has preliminarily determined would confer a high level of protection to 
all workers, irrespective of individual risk factors.
II. Alternatives
a. Alternative 1--Review HIIPP at Least Every Other Year
    Under this regulatory alternative, establishments would need to 
review their HIIPP at least every other year instead of at least 
annually. Therefore, OSHA assumes that costs would be incurred every 
other year including both a designated person's time and the time of 
employees involved in the plan review and update as estimated in 
Section VIII.C., Costs of Compliance.
    As shown in table VIII.F.6., this alternative would reduce the cost 
of the proposed standard by about $86 million. OSHA believes it is 
important that the written program be reviewed and updated annually to 
ensure that any deficiencies are identified and remedied promptly. This 
also maintains consistency with other OSHA standards that require 
annual program review and update.
b. Alternative 2--No Written HIIPP Required for Establishments With <20 
Employees
    This alternative adjusts the number of establishments that do not 
need to have their HIIPP in writing from establishments with ten or 
fewer employees to those with 20 or fewer employees and would reduce 
the cost of the proposed standard by about $2.1 million.
    As discussed above, OSHA believes that the smallest employers can 
effectively administer a program that is not written. However, the 
agency believes that this is less effective for a slightly larger 
employer and, given the fact that employers with between 10 and 20 
employees represents a proportionately large group of covered 
employers, OSHA believes there are benefits to requiring a written 
program for this group of employers.
c. Alternative 3--10-Minute Rest Breaks at the High Heat Trigger
    This alternative revises the rest break requirements at the high 
heat trigger to require 10-minute rest breaks every two hours rather 
than 15-minute rest breaks. The time to walk to and from rest areas are 
maintained at two minutes for indoor employees and four minutes for 
outdoor employees.
    This alternative reduces the cost of the proposed standard by about 
$3.2 billion. OSHA has proposed 15-minute rest breaks based on the 
available literature on rest break efficacy (see Section VII.F., 
Paragraph (f) Requirements at or above the High Heat Trigger).
d. Alternative 4--Refresher Trainings at Least Every Other Year
    Instead of annual refresher trainings, this alternative assumes 
refresher trainings take place every other year for both at-risk 
employees and designated persons. This alternative would reduce the 
cost of the proposed standard by about $238.5 million. Training is a 
highly effective method to protect workers from workplace hazards and 
regular refresher training is necessary to reinforce the topics of the 
training. Training must be frequent enough that employees maintain the 
knowledge necessary to recognize heat-related hazards and to understand 
and comply with the employer's HIIPP. OSHA has preliminarily determined 
that annual training is necessary for employees to maintain the 
requisite knowledge and that it is particularly important for outdoor 
workers to receive this training before the start of each heat season.
e. Alternative 5--95-Degree High Heat Trigger
    The high heat trigger is increased from 90 degrees to 95 degrees 
under this alternative. Revising the high heat trigger upward results 
in fewer hours for which establishments need to implement required 
procedures under these high heat conditions and, thus, results in lower 
costs.
    As shown in table VIII.F.6., this alternative would reduce costs by 
about $1.9 billion (although this is a highly uncertain estimate). 
However, OSHA has preliminarily determined that a high heat trigger of 
a heat index of 90 [deg]F would be highly protective and higher 
triggers may not be adequate for preventing HRIs (see Section V.B., 
Basis for Initial and High Heat Triggers).
f. Alternative 6--Acclimatization for Employees Returning After 30 Days 
Away
    The amount of time away from work that qualifies an employee as a 
returning employee is adjusted from 14 days to 30 days under this 
alternative. While OSHA assumes that two percent of all employees would 
qualify as returning employees given the 14-day qualifying period, the 
agency assumes half a percent of employees would qualify with a 30-day 
period.
    OSHA estimates that this alternative would reduce the cost of the 
proposed standard by about $850,000. Again, this is a highly uncertain 
estimate given the lack of data on the number of workers who are away 
from work for two weeks and those away for 30 days during heat season. 
This affects a small population, and OSHA has proposed the more 
protective approach of requiring acclimatization for workers who have 
been away for 14 consecutive days.
    Are there additional burden reducing alternatives that the agency 
should include that would impact costs to entities? If so, what burden 
reducing alternatives would be most useful to assess these impacts on 
entities? The agency would welcome any suggestions in this area.
H. SBAR Panel Recommendations
    Table VIII.F.7. lists the SBAR Panel recommendations and OSHA's 
responses to these recommendations.

[[Page 70989]]



                                                                                   Table VIII.F.7--OSHA's Responses to the SBAR Panel Recommendations
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                Number                                                   Finding                                                 Recommendation                                             OSHA's response
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
1....................................  SERs expressed concern that the potential standard should not be a ``one    The Panel recommends that OSHA's standard  The agency has drafted a proposed standard that ensures flexibility for
                                        size fits all'' approach and that it would be difficult for a standard to   include performance-based provisions       workplaces. By incorporating elements that can be tailored to the
                                        reasonably and effectively cover heat hazards in all settings and all       where practical to allow employers to      workplace, OSHA is effectively addressing concerns of applicability to
                                        regions of the U.S. SERs agreed that an OSHA standard should be flexible    tailor their heat injury and illness       various workplace settings while establishing minimum requirements that
                                        with a programmatic approach that allows employers to tailor their          prevention program to their setting and    are intended to ensure the heat injury and illness prevention program
                                        program to their particular workplace. SERs thought this flexibility was    situations, including the local climate    remains effective and accessible to employees. For example, the proposed
                                        necessary for employers to prevent heat-related injuries and illnesses in   and the type of work being performed,      standard does not apply to indoor workplaces where air conditioning
                                        their workplace most effectively. Some SERs thought the employer should     and also taking into consideration the     consistently keeps the ambient temperature below 80[deg]F, the proposed
                                        determine what approaches should be implemented to address heat based on    size and complexity of the employer's      standard only requires employers with 10 or more employees to have a
                                        the conditions in their work settings as long as those approaches adhere    operations. To the extent practicable,     written plan, allows employers to choose the heat metric that works best
                                        to the regulatory framework. One SER asked whether the regulatory text,     the Panel recommends that OSHA offer       for their workplace, and make other determinations based on their
                                        like the regulatory framework provided to SERs, could list multiple         multiple methods of compliance with        employee operations. OSHA requests further comment on the flexibility of
                                        options employers can choose from.                                          provisions of a heat standard.             the provisions included in the proposed heat standard.
2....................................  SERs felt that the heat triggers that OSHA had suggested in the regulatory  In light of input received from SERs, the  The agency has provided a discussion of the methodology for determining
                                        framework were too low and questioned whether the heat triggers were        Panel recommends that OSHA consider        the initial and high heat triggers in Section V.B., Basis for Initial and
                                        appropriate across different regions of the U.S. Some SERs reported         whether the heat trigger levels            High Heat Triggers, which cites both observational and experimental
                                        finding OSHA's table of heat triggers presented in the regulatory           presented in the regulatory framework--    evidence. OSHA simplified the triggers that were initially presented in
                                        framework and the use of an initial and a high heat trigger to be           both the initial and high heat triggers--  the regulatory framework; there are no longer ambient temperature
                                        confusing and stressed that OSHA should keep the requirements simple.       are too low, and also recommends that      triggers or separate, lower forecast triggers. OSHA has also provided
                                        SERs also asked how the heat triggers had been determined and whether       the agency present these heat triggers     evidence that higher triggers, including the NWS heat advisories, would
                                        they were scientifically based. However, other SERs supported having two    as simply as possible to avoid             not be protective enough.
                                        trigger levels and some reported that they had already implemented          confusion. The Panel also recommends
                                        policies based on multiple trigger points already. Some SERs suggested      that OSHA provide the methodology used
                                        using the National Weather Service heat advisory as a single measure for    to select the heat triggers, including
                                        a heat trigger tailored to local conditions.                                any scientific evidence or other
                                                                                                                    supporting data, along with
                                                                                                                    consideration of potential alternatives.
2....................................  A few SERs voiced strong concerns about the underlying data on heat         The Panel recommends that OSHA clearly     The agency has provided a discussion of the data on occupational heat-
                                        related injuries and illnesses. SERs felt that the numbers of illnesses,    present the data being used to justify a   related injuries, illnesses, and fatalities in Section V.A., Risk
                                        injuries, and fatalities reported in the BLS data are low relative to the   potential standard. The Panel recommends   Assessment, and Section VIII.E., Benefits, including the significant
                                        total number of employees nationally, suggesting that any action or         that OSHA thoroughly explore whether and   likelihood of underreporting of such data. The agency relied on publicly
                                        change is unnecessary. One SER thought that the number of heat illnesses    how the injury, illness, and fatality      available data from BLS, State health departments, and the peer-reviewed
                                        and injuries is statistically insignificant, given the millions of          data support the promulgation of a heat    literature. OSHA discusses the need for the standard in Section III.B.,
                                        workers in the labor force. SERs requested clarification on these data      standard.                                  Need for Proposal, and whether the threshold for agency action is met in
                                        including requests that the data on heat-related injury and illness be                                                 Section VI., Significance of Risk.
                                        published in the record by detailed industry.
3....................................  Many SERs questioned whether the recordkeeping requirements that OSHA had   The Panel recommends that OSHA reconsider  OSHA is proposing requirements in this section, based in part on feedback,
                                        suggested were necessary. Some SERs thought they would have to hire         or simplify recordkeeping of temperature   which will allow more flexibility for workplaces. Employers of only
                                        additional staff or take time away from other safety initiatives to         monitoring and not require documentation   indoor workplaces will be required to create written or electronic
                                        complete the paperwork outlined in the regulatory framework. SERs thought   of rest breaks unless the agency can       records of on-site temperature measurements and retain these records for
                                        that documenting rest breaks would be infeasible, and that recordkeeping    show that such a requirement is            a minimum of six months. Employers have flexibility on how they can
                                        of daily temperature monitoring was unnecessary and would be burdensome     necessary or appropriate to protect        comply with the recordkeeping requirement by using monitoring devices
                                        to comply with.                                                             workers. The Panel also recommends that    with sufficient storage capability, or employers could comply by creating
                                                                                                                    OSHA reconsider other potential            and maintaining written records based on monitoring devices that do not
                                                                                                                    recordkeeping to determine if those are    have digital recording capabilities. OSHA has determined that this
                                                                                                                    necessary or appropriate and whether       provision would have a positive impact on worker safety and health by
                                                                                                                    they positively impact worker safety and   assisting OSHA in determining conditions at the worksite, and aiding
                                                                                                                    health.                                    employers to identify trends in indoor temperatures and their effect on
                                                                                                                                                               employee health and safety. In part based on feedback, OSHA is not
                                                                                                                                                               requiring documentation of rest breaks.

[[Page 70990]]

 
4....................................  SERs raised concerns about recordkeeping of heat related injuries and       The Panel recommends that OSHA not         OSHA is not proposing to require additional injury and illness reporting
                                        illnesses requiring only first aid. Other SERs asked why OSHA is            include a requirement for recording        beyond what is required by the existing Recordkeeping standard (29 CFR
                                        considering requiring records of first-aid-only injuries and illnesses      first-aid-only heat-related illnesses or   1904.7). The only proposed recordkeeping requirement applies to
                                        that are heat-related while not requiring records of first-aid-only         injuries unless the agency can             monitoring data collected for indoor work areas.
                                        injuries and illnesses that are not heat-related. Some SERs stated it was   demonstrate some particular
                                        unclear what first aid means regarding heat illness with one SER            circumstances where such a requirement
                                        wondering whether asking workers to take a break and hydrate because they   is necessary or appropriate to protect
                                        appear to be hot would need to be captured as a first-aid incident.         workers when such records are not
                                                                                                                    required under OSHA's general injury and
                                                                                                                    illness recordkeeping regulation.
5....................................  Many SERs reported already monitoring the temperature at their facility or  The Panel recommends that OSHA allow       The agency has drafted a proposed standard that would provide flexibility
                                        job sites. SERs relied on various heat assessment methods including the     flexibility in monitoring methods and      to employers in both what heat metric they can use and how they are
                                        OSHA/NIOSH Heat Safety Tool App, local weather forecasts, the National      not mandate a single method that           required to monitor the worksite (including allowing outdoor employers to
                                        Weather Service's online calculator or measuring temperature with           employers must use to measure heat in      use the forecast instead of on-site monitoring). OSHA provides guidance
                                        standard thermometers, heat index monitors, or wet bulb globe               their workplace or on their worksite.      on how and when monitoring must occur.
                                        thermometers. Some SERs thought terms like ``wet/dry bulb temperature''     The Panel also recommends that OSHA
                                        and ``heat index'' would be confusing while other SERs thought that         clarify how and when temperature
                                        measurements with a WBGT was complicated and may be difficult for some      monitoring must occur for all employers
                                        employers to use. SERs told the Panel about some difficulties they have     but especially for those with indoor
                                        with measuring temperature at their locations. SERs with indoor worksites   settings and those with mobile
                                        said that the temperature can vary across different parts of their          workforces.
                                        facility. SERs with workers who are mobile and work at many different
                                        locations or elevations throughout the day said that temperature
                                        monitoring was a challenge for them because of various complicating
                                        factors.
6....................................  The majority of the SERs said that they allowed their employees to take     The Panel recommends that OSHA consider    The proposed standard only requires rest breaks at the initial heat
                                        rest breaks when they needed to, but many objected to OSHA including a      allowing employers some flexibility, to    trigger when they are needed to prevent overheating. Under the high heat
                                        specific frequency or duration of breaks in a rule. Some SERs said that     the extent feasible within the             trigger, a minimum of a 15-minute paid rest break would be required every
                                        shorter, more frequent breaks might be ideal sometimes, while others said   constraints of the OSH Act, in the         two hours because of increased risk of HRI at and above the high heat
                                        that the intensity of the job or other personal, physiological              frequency of any rest breaks required in   trigger, but some flexibility is provided by allowing a meal break to
                                        characteristics may make more frequent breaks necessary. Some SERs          a rule. The Panel also recommends that     count as a rest break. Proposed provisions under the initial heat trigger
                                        thought that giving 15-minute breaks every two hours would be unworkable    OSHA clarify where workers can take        specify the requirements for indoor and outdoor break areas and provide
                                        in their situation. SERs in construction and manufacturing reported that    breaks and provide the maximum             flexibility by allowing employers to choose from different options of
                                        there were times that work could not simply stop while workers took         flexibility possible to employers to       cooling methods in the break area (e.g., shade OR air conditioning for
                                        breaks (e.g., while pouring concrete, during certain industrial             determine what works best for their        outdoor break areas; air conditioning OR increased air movement and, if
                                        processes). In these cases, SERs reported that they rotated workers         employees and situation. The Panel         appropriate, de-humidification for indoor break areas). The summary and
                                        between more and less strenuous tasks. SERs with workers who wear complex   further recommends that OSHA clarify       explanation for rest breaks under the high heat triggers clarifies that
                                        PPE (e.g., construction, tree care, electric power) reported that their     what, if any, activities employees can     no work activities would be allowed during rest breaks.
                                        employees sometimes prefer to finish their work rather than stop for a      engage in during rest breaks.
                                        break which would require removing and redonning their PPE. SERs whose
                                        employees worked at heights (e.g., roofing, telecommunications towers)
                                        expressed concern that these employees could be put in more danger if
                                        they were required to climb down from their working position for a break
                                        and back up afterwards. These SERs wondered if breaks needed to occur in
                                        a certain location like a shaded area on the ground or in an air-
                                        conditioned vehicle. A number of other SERs similarly wondered whether
                                        they had to provide air-conditioned break areas and require their
                                        employees take rest breaks in those areas. Some SERs said that their
                                        workers preferred to take breaks in non-air-conditioned spaces like
                                        shaded outdoor areas. A few SERs wondered whether other activities
                                        including things like downtime while waiting for materials to be
                                        delivered, toolbox talks or job briefings, engaging in non-strenuous work
                                        tasks, or driving between jobs could be considered breaks.

[[Page 70991]]

 
7....................................  SERs universally reported supplying drinking water to their employees       The Panel recommends that OSHA consider    OSHA is including the term ``suitably cool'' in the proposed standard to
                                        generally with reusable bottles and water coolers, single use water         eliminating or better defining the term    provide flexibility to employers and maintain consistency with the field
                                        bottles, or plumbed fountains or faucets. While SERs acknowledged the       ``suitably cool'' to provide clarity and   sanitation standard (29 CFR 1928.110), which has incorporated a
                                        necessity of supplying drinking water, some objected to some of the         take employee needs and preferences into   ``suitably cool'' requirement since it was promulgated in 1987. The
                                        specified potential requirements in the regulatory framework. One SER       account. The Panel also recommends that    phrase is also used in California's heat standard for outdoor workplaces
                                        felt that the amount of water specified as required was too much. Some      OSHA provide clarity on methods for        (Cal. Code Regs. tit. 8, section 3395). As discussed in Risk Reduction,
                                        SERs thought that the phrase ``suitably cool'' was vague and did not take   complying with any potential               Section V.C., the temperature of drinking water impacts hydration levels,
                                        into account employee preferences for their water temperature.              requirements related to the provision of   as cool or cold water has been found to be more palatable than warm
                                                                                                                    water and allow for flexibility, when      water, thus leading to higher consumption of cool water and decreased
                                                                                                                    appropriate, in the amount of water        risk of dehydration. Additional evidence highlighted in Section V.C.,
                                                                                                                    required to be provided.                   Risk Reduction, shows that cool fluid ingestion has beneficial effects
                                                                                                                                                               for reducing heat strain. OSHA provides additional guidance on what it
                                                                                                                                                               considers ``suitably cool'' in the Explanation of Proposed Requirements
                                                                                                                                                               section of the proposed provision. OSHA is specifying the amount of water
                                                                                                                                                               that employers need to provide to employees, not an amount that employees
                                                                                                                                                               need to drink. OSHA provides guidance for how employers can comply with
                                                                                                                                                               the provision of 1 quart of cool water every hour.
8....................................  Many SERs objected to OSHA's option in the regulatory framework for         The Panel recommends that OSHA provide     OSHA preliminarily finds that acclimatization is an effective preventative
                                        gradual acclimatization to heat, requiring employees to gradually ramp up   multiple options for acclimatization in    measure for preventing HRI and fatalities in unacclimatized workers. The
                                        their exposure to heat over the course of a few days. Several SERs said     the rule to allow employers flexibility    proposed standard provides options for how to protect unacclimatized
                                        that if they force employees to work fewer hours due to acclimatization     in determining the best method for         workers. The proposed standard provides a gradual exposure option as well
                                        requirements, these workers might just quit and look elsewhere for work.    acclimatizing their workers.               as an option for employers to implement the requirements at the high heat
                                        Other SERs reported that they must pay their union laborers for a minimum                                              trigger during an employee's first week of work. OSHA requests further
                                        of four hours regardless of whether they worked that full time meaning                                                 comment on the proposed acclimatization provision and on a number of
                                        that the SERs would be paying for time not worked during the                                                           topics relating to acclimatization, including acclimatization during heat
                                        acclimatization period. Other SERs said it would not be possible to move                                               waves, acclimatization following illness, requests for examples of
                                        workers to light duty jobs during the acclimatization period either                                                    existing acclimatization programs and the clarity of the explanation of
                                        because they did not have enough of that type of work or because light                                                 ``similar heat conditions.''
                                        duty tasks were not available at their workplaces. Some SERs thought that
                                        strictly prescribed acclimatization requirements were unnecessary because
                                        new workers they hired were either from the area and used to the weather,
                                        were coming from jobs where they performed similar tasks in similar
                                        conditions, or only those who were fit and able to work in hot weather
                                        would ``self-select'' into the types of jobs they offered. Many SERs
                                        reported having some form of enhanced supervision or ``buddy system'' for
                                        workers who were acclimatizing to the hot working conditions. Some said
                                        that new workers worked alongside supervisors during their first weeks on
                                        the job which allowed for supervision of their heat tolerance. Others
                                        said that the training process where new employees are learning and
                                        working up to doing the jobs fully and on their own serves as an
                                        acclimatization process.
9....................................  SERs raised a number of concerns about applying a heat standard to workers  The Panel recommends that OSHA address     OSHA is proposing to establish heat triggers using a measurement of the
                                        who work alone and workers who move between job locations throughout the    the unique situations of employers whose   Heat Index which is more readily available through local forecast data or
                                        day. SERs mentioned that they were not sure how they would have to          employees work alone and/or travel to      heat monitoring apps. As discussed in this preamble, employers do not
                                        monitor the temperature when workers were working at multiple locations     many worksites each day and offer          need to monitor all work locations continuously and are only required to
                                        since employees could cover a large range with varying climate conditions   flexibility to these employers and         verify whether the temperature exceeds the triggers in order to implement
                                        throughout their workday. One SER said it was not clear what areas need     clarify the employer's responsibilities    the applicable protective measures. OSHA recognizes that employees
                                        to be routinely monitored if the work site is not fixed while others were   for employees in these circumstances.      working alone can be at a greater risk for HRI due to the lack of
                                        concerned that tracking the temperature forecasts and relevant heat                                                    immediate assistance or interventions. Therefore, OSHA has proposed that
                                        triggers for the worksite that each worker or crew is visiting that day                                                the employer maintain a form of two-way communication and regularly
                                        would be difficult. SERs said that such tracking becomes a greater                                                     communicate with employees. When the high heat trigger is met or
                                        challenge if each worker or crew visits multiple worksites within a day.                                               exceeded, the proposed standard would further require employers to stay
                                        SERs were also concerned that it would be difficult to monitor workers                                                 in contact at least every two hours with employees working alone.
                                        who work alone. SERs mentioned that it would be difficult to ensure that                                               Requirements for safety and health procedures when employees are working
                                        employees are taking required breaks with one SER saying that they                                                     alone are not unique to this rule. OSHA believes that the employer
                                        believed this would become more difficult if mandated rest break                                                       responsibilities outlined under the proposal are necessary to ensure the
                                        durations depend on whether the temperatures were at or above the initial                                              safety of workers.
                                        heat trigger or high heat trigger. Other SERs mentioned the difficulty of
                                        monitoring employees for signs and symptoms of heat injury and illness
                                        when employees are working alone. While some had equipment that monitored
                                        an employee's movement and reported to the employer if that movement
                                        stopped or procedures for regular check-ins via phone or tablet
                                        applications, other SERs said that they would not be able to implement a
                                        buddy system or close supervision of employees given the work
                                        arrangements.

[[Page 70992]]

 
10...................................  Almost all SERs agreed that training is one of the most important steps an  The Panel recommends that OSHA include a   OSHA preliminarily finds that it is necessary to train employees so they
                                        employer can take to prevent heat injury and illness in their workers.      robust training provision in a heat        can recognize heat-related hazards and understand the appropriate steps
                                        SERs mentioned that they already provide some form of training on heat      standard. The Panel also recommends that   they can take to minimize potential health effects in themselves and
                                        injury and illness prevention including recognition of signs and symptoms   OSHA continue to provide support for       coworkers. Training on the employer's policies and procedures to address
                                        and how to respond and other topics including the importance of staying     employer training efforts by providing     heat hazards would be an essential part of this proposed standard because
                                        hydrated (electrolytes or water); working at a comfortable pace;            training materials, sample curriculum,     it would help to ensure that employees understand heat hazards, the
                                        contacting a supervisor to get an extra break or water; accessing and       videos, and/or other methods.              workplace-specific control measures that would be implemented to address
                                        locations of cool down areas; sleeping well and being well rested;                                                     the hazard, and the requirements of the proposed standard. OSHA has
                                        acclimatizing; and medical treatment of heat-related illnesses and                                                     provided guidance on how employers can comply with the training provision
                                        injury. Training was reported to be provided in both formal and informal                                               and expects to provide sample training materials and other compliance
                                        settings including regular training classes and tailgate or toolbox                                                    assistance products to assist employers in implementing the requirements
                                        talks. Several SERs felt that a heat standard be centered around                                                       of the proposed standard if promulgated.
                                        training; one SER thought that a heat standard should mandate training
                                        while questioning the necessity and usefulness of other potential
                                        requirements.
11...................................  SERs reported a mix of informal and formal heat injury and illness          The Panel recommends that OSHA include a   OSHA is proposing a requirement for a heat injury and illness prevention
                                        prevention programs. Some said that they do not have a program that is in   requirement for a written heat injury      plan (HIIPP) as a provision of the standard. The proposed HIIPP
                                        written form; while others said they have a written program that is         and illness prevention program that        requirement allows employers the flexibility to tailor their plans to
                                        relatively short in length (i.e., in bullet points). SERs were largely      allows employers the flexibility to        their specific industry location and work activities. OSHA understands
                                        supportive of the idea of a written program or plan. SERs said that they    tailor their plans to their specific       that a HIIPP must be adaptable to the physical characteristics of the
                                        believe a written plan could be beneficial and one SER said that their      industry, location, and activities. The    work site and the job tasks performed by employees, as well as the
                                        heat plan reduced the number of first-aid and more serious safety           Panel also recommends that OSHA consider   hazards identified by the employer when designing their HIIPP. To
                                        incidents, reduced workers' compensation costs, and maybe improved          an exemption for very small employers      increase flexibility, in cases where employers have multiple work sites
                                        absenteeism. SERs said that employers should have flexibility to develop    from the requirement for the plan to be    that are substantially similar, the HIIPP may be developed by work site
                                        and implement such plans. Some SERs supported the potential exemption in    in writing. The Panel further recommends   type rather than by individual work sites so long as any site-specific
                                        the regulatory framework for very small employers (e.g., those with 10 or   that, unless the agency determines that    information is included in the plan (e.g., phone numbers and addresses).
                                        fewer employees) from the requirement for the plan to be in writing; one    it is appropriate to do otherwise,         The proposed HIIPP requirement is consistent with the SBAR Panel's
                                        SER stated that requiring a written plan would place significant burden     review and update of the plan be           recommendation and requires that only employers with more than 10
                                        on these employers. Most SERs agreed that, if the standard required         required annually and if updates are       employees need to have a written plan. For employers with 10 or fewer
                                        updates of a written plan, that requirement should be for annual reviews    required in additional situations that     employees, the agency does not believe that there is a high likelihood of
                                        and updates. One SER commented that they believed option to review and      those situations be clearly delineated     misunderstanding when employers communicate their HIIPPs to employees
                                        update ``whenever necessary to ensure ongoing effectiveness'' or            to reduce confusion and ambiguity.         verbally. Employers with existing plans would be required to modify and/
                                        ``whenever a heat-related illness or injury occurs'' were vague and/or                                                 or update their current HIIPP plans to incorporate any missing required
                                        unclear.                                                                                                               elements and provide training on these new updates or modifications to
                                                                                                                                                               all employees. Furthermore, to delineate requirements surrounding HIIPP
                                                                                                                                                               reviews and updates more clearly, OSHA is proposing to require the
                                                                                                                                                               employer to review and evaluate the effectiveness of the HIIPP whenever a
                                                                                                                                                               heat-related injury or illness occurs that results in death, days away
                                                                                                                                                               from work, medical treatment beyond first aid, or loss of consciousness,
                                                                                                                                                               but at least annually. Following each review, the employer would be
                                                                                                                                                               required to update the HIIPP as necessary. OSHA preliminarily finds that
                                                                                                                                                               a heat-related injury that results in death, days away from work, medical
                                                                                                                                                               treatment beyond first aid or loss of consciousness warrants an
                                                                                                                                                               evaluation of the HIIPP because it could potentially indicate a
                                                                                                                                                               deficiency of the HIIPP. OSHA provides more information in Section
                                                                                                                                                               VII.C., Explanation of Proposed Requirements, of the HIIPP requirement.
12...................................  SERs disagreed with some specific time and cost estimates that were         The Panel recommends that OSHA review      All time and cost estimates provided in the SER background document were
                                        provided in the SER background document. SERs thought that OSHA's           time and cost estimates in the economic    reviewed and revised for the NPRM where appropriate with consideration
                                        estimates for the amount of time it would take to develop the written       analysis and revise where appropriate to   for SERs feedback and experience. As a result, travel time (time spent
                                        plan and to conduct the hazard analysis were both too low as were the       take the experience and feedback of the    going to and from the break area) is added to the rest break costs. OSHA
                                        estimates related to monitoring of employees, measuring or calculating      SERs into account.                         is not proposing additional requirements for recordkeeping for heat-
                                        the heat index or temperature, and recording heat-related illnesses or                                                 related illnesses or injuries in the proposed standard, so it no longer
                                        injuries. One SER said that OSHA's estimate of breaks was too low because                                              requires a cost estimate. For some estimates, OSHA's review determined
                                        it only counted the break time but did not account for the time spent                                                  that the estimates in the SER background document were appropriate (e.g.,
                                        going to and from the break area.                                                                                      outdoor monitoring costs). In other cases, OSHA determined that the
                                                                                                                                                               estimates in the SER background document overestimated costs or did not
                                                                                                                                                               account for overlap between provisions and therefore reduces the
                                                                                                                                                               estimates (e.g., indoor hazard assessment).

[[Page 70993]]

 
13...................................  Most SERs with indoor settings reported using some form of ventilation and  The Panel recommends that OSHA offer as    OSHA has drafted the rule to allow maximum flexibility in implementing
                                        air movement to cool their facilities. However, many of these SERs said     much flexibility as possible to allow      engineering controls while still protecting workers. The agency has
                                        it would be infeasible to lower the temperature using air-conditioning      employers to implement engineering and     attempted to minimize feasibility issues by providing employers with
                                        because their buildings were too large to do this effectively. A few SERs   administrative controls that are           multiple engineering control options for compliance, allowing them to
                                        said they are limited in where they can place fans due to work processes    feasible and appropriate for their         select the controls that can be most effectively implemented. OSHA
                                        or risk of contamination of materials or the air. Some SERs also said       workplace and activities.                  believes that the proposed control options are important and needed to
                                        that they could not use some of the engineering controls discussed in the                                              adequately protect workers from HRIs as discussed in the Explanation of
                                        background documents such as misting fans (which could introduce slipping                                              Proposed Requirements.
                                        hazards or damage materials) or portable shelters (which cannot be used
                                        on work surfaces such as roofs). Other SERs discussed the difficulties of
                                        implementing engineering controls in buildings they do not own or when
                                        working on in-progress construction projects. SERs also questioned
                                        whether some administrative controls suggested in the background
                                        materials would work for their setting. While some SERs said they
                                        adjusted work start and stop times to avoid working during the hottest
                                        part of the day, some SERs said they were unable to do so, for example,
                                        because they could not work too early in residential areas or because
                                        employees preferred a later start time. Some SERs said they used text
                                        messages or other electronic communications to remind employees of or
                                        alert them to heat hazards. Some SERs whose employees spend a significant
                                        part of their day driving worried that sending their employees electronic
                                        notifications would distract them and put them at risk of motor vehicle
                                        accidents. Many SERs were, however, supportive of the idea of monitoring
                                        employees for signs and symptoms of heat illness and injury. Some SERs
                                        reported that they utilized a ``buddy system'' where employees monitored
                                        each other, or supervisors monitored employees, for signs and symptoms of
                                        heat illness or injury. Some SERs said they have found this practice very
                                        useful in reducing illnesses and injuries related to heat. Some SERs
                                        reported that they use technology like electronic monitors or check-ins
                                        via cell phone or tablet although SERs whose employees are mobile
                                        reported that that can be difficult if the employee is in a location with
                                        limited cell service. SERs suggested that biometric monitors or self-
                                        monitoring of urine color to determine hydration levels could be useful
                                        as well.
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[[Page 70994]]

G. Distributional Analysis

I. Impact of Heat on Underserved Populations
    Executive Order 13985, ``Advancing Racial Equity and Support for 
Underserved Communities through the Federal Government,'' directs 
Federal agencies to conduct an equity assessment on a subset of the 
agencies' programs and policies. OSHA has chosen to include an equity 
assessment regarding the proposed standard for Heat Injury and Illness 
Prevention in Outdoor and Indoor Work Settings and the potential impact 
on economically or historically underserved populations. The purpose of 
an equity assessment is to analyze the distribution of regulatory 
impacts across individuals, households, and businesses/industries, with 
particular attention to economically or historically underserved or 
vulnerable groups. This assessment, which is entirely separate from 
OSHA's legal findings and rationale supporting the proposed standard 
for Heat Injury and Illness Prevention in Outdoor and Indoor Work 
Settings, concludes that the proposed standard would have a positive 
impact on underserved populations (e.g., low-income and Hispanic 
workers) by providing workplace protections from extreme temperatures 
that have a disproportionate impact on occupations held by individuals 
from underserved communities.
A. Heat Exposure of Workers by Socioeconomic Status
    Extreme temperatures affect the entire economy and pose a 
significant risk to individuals employed in workplaces (see Section 
II.B., Need for Proposal and Section II.C., Events Leading to the 
Proposal). This threat is unevenly distributed across demographic and 
socioeconomic groups, exacerbating inequalities. Individuals from 
underserved populations are more likely to work in occupations with 
heat-related risks (Ndugga et al., 2023). Evidence from the American 
Community Survey covering 2018-2022 (Ruggles et al., 2024) suggests 
that workers from historically underserved groups in core industries 
(see Section VIII.B.II.A., Potentially Affected Industries) have 
greater exposure to occupational heat-related hazards, with more severe 
outcomes that impact their ability to work. That includes, for example, 
exposure to high outdoor temperatures, radiant heat sources, or 
insufficient temperature control or ventilation in indoor work 
settings. The methodology to estimate exposure by demographic group is 
outlined in detail in appendix C.
    Figure VIII.G.1 shows that workers from low-income households are 
disproportionately exposed to heat-related hazards in (1) indoor work 
settings that emit heat during the production process, (2) indoor work 
settings that have inadequate climate control, or (3) outdoor work 
settings (see exposure definitions in Section VIII.B., Profile of 
Affected Industries). This is non-trivial as occupational injuries and 
illnesses cost the average worker $35,000 with wide-reaching health 
impacts including the threat of death (Leigh, 2011; Ndugga and Artiga, 
2023; Park et al., 2021).\104\ Thus, workers from low-income households 
who are often challenged with affording in-home air conditioning (Mann 
and Schuetz, 2022) face a concurrent burden: threat of costly workplace 
heat hazards.
---------------------------------------------------------------------------

    \104\ Note that this estimated cost to workers is different from 
the Value of a Statistical Injury (VSI) used to estimate benefits in 
Section VIII.E., Benefits. The VSI is an estimate of individuals' 
desire to avoid an illness or injury and calculates the willingness 
to pay to avoid said illness or injury. The $35,000 quoted reflects 
the average social cost of a workplace injury reported to workers 
compensation in 2021$.
---------------------------------------------------------------------------

    Workers from low-income households are most vulnerable to 
occupational heat exposure across all phases of their careers. For 
example, workers aged 16 to 64 from households in the lowest income 
deciles face elevated indoor and outdoor exposure to heat-hazards (see 
Figure VIII.G.2.). The highest levels of exposure occur among workers 
aged 35-54 earning less than $60,000 (approximately 15 percent in 
indoor and outdoor workplaces). This high level of exposure occurs 
during these workers' peak earning years, posing a threat to not only 
health but also lifetime earnings which can facilitate socioeconomic 
mobility (see Figure VIII.G.2., Panels B and C).
    Figures VIII.G.3. and VIII.G.4. show that there is variation in 
exposure among low-income workers by sex, ethnicity, and race. While 
low-income individuals from some underserved backgrounds have heat 
hazard exposure levels exceeding 10 percent of the worker population 
(e.g. workers identifying as female, Black, multi-racial), male and 
Hispanic workers have the highest level of exposure to workplace heat 
hazards. Men earning less than $60,000 are nearly twice as likely to be 
exposed to workplace heat-related hazards than women, peaking at 17 
percent for men working in non-climate controlled indoor settings and 
19 percent for men working in outdoor settings.\105\ Similarly, 
respective exposure to workplace heat hazards ranges from 16 percent to 
19 percent in non-climate controlled indoor and outdoor settings among 
low-income Hispanic workers.
---------------------------------------------------------------------------

    \105\ For context, in 2022, the median annual earnings of men in 
the United States was $62,350 (Ruggles et al., 2024).
---------------------------------------------------------------------------

    Despite evidence of elevated exposure along the socioeconomic 
gradient, research finds that many of the most vulnerable workers have 
minimal to no workplace protections to manage occupational heat stress 
(Morrissey-Basler et al., 2024; Luque et al., 2019; Flocks et al., 
2013). Although workers are aware of the health consequences of 
exposure to occupational heat stress, they report a feeling of lack of 
control over the condition of their work setting (Flocks et al., 2013). 
In the absence of formal workplace protections, some vulnerable workers 
assume responsibility for and implement heat stress management 
practices to preserve their well-being rather than view the employer as 
the arbitrator for protection against occupational heat hazards (Luque 
et al., 2019). Some of these worker-initiated heat stress prevention 
strategies may not be grounded in evidence-based science. Lack of 
employer safeguards against elevated temperature can, in turn, 
reinforce disparities in occupational heat exposure that leave the most 
vulnerable workers overexposed to preventable heat-induced injuries, 
illnesses, and fatalities.
BILLING CODE 4510-26-P

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[GRAPHIC] [TIFF OMITTED] TP30AU24.003

BILLING CODE 4510-26-C
B. Productivity and Health Effects
    The figures above show the fraction of workers who are exposed to 
workplace heat-related hazards and therefore likely to be covered by 
the proposed standard. Under an assumption that benefits of the 
standard correspond 1-for-1 to coverage, this fraction can be 
translated into the fraction of workers benefiting from the standard. 
In other words, translating the results from the figures

[[Page 70999]]

into benefits from the standard in terms of increased productivity, 
improved health, or other outcomes makes the assumption that all work-
related exposure to heat is explained by industry and occupation. This 
assumption could over- or under-state the exposure to heat on the job 
that workers face. As a recent study of heat and occupational injuries 
discusses (Park et al., 2021), if there are compensating differentials 
for the risk associated with heat exposure, then workers exposed to the 
risk would be paid higher wages. This could be the case even within 
industry and occupation categories. Alternatively, if workers and 
employers negotiate over total compensation from income and amenities, 
then a worker could receive both lower wages and higher heat exposure 
(a workplace disamenity) due to imperfectly competitive labor markets 
\106\ (Burdett and Mortensen, 1998; Sorkin, 2018).
---------------------------------------------------------------------------

    \106\ The existence of jobs with different working conditions, 
in conjunction with variation in worker preferences, could in effect 
be the source of firms' power in the labor market that allows them 
to lower wages in the first place (Card et al., 2018).
---------------------------------------------------------------------------

    Existing studies on workplace-related heat exposure do not 
currently say which of these two possibilities holds within industry 
and occupation groups. A recent review summarizes research on the 
effect of temperature on labor productivity (Lai et al., 2023). The 
focus of the literature has been on educational outcomes, cross-country 
comparisons, or cross-industry effects. Recent work on intensive-margin 
labor supply (i.e., hours worked) and heat exposure in the U.S. shows 
that whether or not the industry of workers is controlled for in the 
statistical model does not largely change the estimated effect of heat 
exposure on time spent working (Neidell et al., 2021). This result 
indicates that industry-level differences in exposure to heat do not 
fully capture the effect of heat on labor supply. The study does not 
control for occupation group, so exposure within versus across 
occupations cannot be parsed.
    An analysis of workplace injuries and heat exposure in California 
examines the distribution of heat-related occupational injuries (Park 
et. al., 2021). The analysis is done using California Department of 
Workers' Compensation data, and the injuries are geocoded at the zip 
code of the worksite. In an analysis that controls for zip code-by-
month and county-by-month-by-year fixed effects (as well as 
precipitation), the authors find that for the average worker, injuries 
go up on days with temperature above 90 [deg]F. The increase in 
injuries is 36 percent larger for workers in the lowest income quintile 
compared to workers in the highest income quintile.\107\ The analysis 
also examines effects by worker age and sex. It finds that workers 
younger than 30 years of age are 3 times more likely to experience a 
workplace injury on a day about 90 [deg]F compared to a worker older 
than 60.\108\ Male workers are 2.3 times more likely to experience 
injury compared to female workers.\109\
---------------------------------------------------------------------------

    \107\ The point estimate for workers in the lowest quintile 
indicates a 0.0735 increase in injuries per day above 90 [deg]F for 
the lowest quintile and a 0.0541 increase for workers in the highest 
quintile.
    \108\ A point estimate of 0.0773 versus 0.0257.
    \109\ A point estimate of 0.0837 versus 0.0359.
---------------------------------------------------------------------------

    If the controls in the statistical model substantially account for 
differences in heat exposure due to industry and occupation (for 
instance, because industries and occupations are segmented across zip 
codes), then the effect would suggest that the distribution of exposure 
percentages could be a lower bound on the distribution of realized 
benefits from the proposed standard stemming from reduced workplace 
injuries. Further analysis that explicitly accounts for industry and 
occupation-based exposure to heat would be useful to determining the 
extent to which workers within industry and occupation groups are 
differentially affected by heat-related occupational injuries.
II. Averted Injuries, Illnesses, and Fatalities by Socioeconomic Status
    Table VIII.G.1. shows the estimated number of workplace heat-
related injuries and illnesses (HRIs) as well as heat-related 
fatalities averted by the proposed standard for Heat Injury and Illness 
Prevention in Outdoor and Indoor Work Settings.\110\ Table VIII.G.1., 
columns 1 and 3, present the pre-standard estimate of HRIs and heat-
related fatalities. HRIs and heat-related fatalities are concentrated 
among workers who are low-income, in peak earning years (aged 35--54), 
male, or Hispanic. These vulnerable populations averaged 1,066 HRIs and 
7 heat-related fatalities each year.
---------------------------------------------------------------------------

    \110\ The methodology to derive exposure is detailed in appendix 
C.
---------------------------------------------------------------------------

    The Agency provides an example of the downstream impact of these 
consequential health events on firm costs in table VIII.G.2. The 
estimated cost to the employer of an HRI, such as heat prostration (or 
exhaustion), is $79,081 assuming a 3 percent profit 
margin.111 112 Thus populations with more HRIs elevate firm 
cost (see table VIII.G.2., column 2). The extent to which the employer 
bears the full costs depends on the nature of their workers' 
compensation insurance policy. Nonetheless, the demographically 
disaggregated cost of projected HRIs suggests that concentrated efforts 
to reduce events among the most vulnerable populations can serve as a 
meaningful mechanism to reduce firm cost.
---------------------------------------------------------------------------

    \111\ Total costs include a direct cost of $37,658 and indirect 
costs of $41,423.
    \112\ The estimate is derived using OSHA's Safety Pays Program's 
``Estimated Costs of Occupational Injuries and Illnesses and 
Estimated Impact on Company's Profitability Worksheet'' https://www.osha.gov/safetypays/estimator. The tool projects and estimate of 
how injuries and illnesses may impact company's profitability. The 
above example assumes a 3 percent profit margin for heat prostration 
(or exhaustion) that cost $79,081 (i.e., includes a direct cost of 
$37,658 and indirect costs of $41,423).
---------------------------------------------------------------------------

    The Agency estimates that the proposed standard will reduce HRIs 
and heat-related fatalities among exposed workers by 65 and 95 percent, 
respectively (for more discussion, see Section VIII.E., Benefits). 
Table VIII.G.1., columns 2 and 4, present the projected average number 
of HRIs and heat-related fatalities averted by demographic group. The 
largest benefits are accrued to populations with heightened exposure: 
low-income, in peak earning years (aged 35-54), male, and Hispanic 
workers. This, in the case of heat prostration (or exhaustion), 
translates into an approximate 34 percent reduction in total firm costs 
among the respective demographic groups with heightened exposure (see 
table VIII.G.2., column 5).

[[Page 71000]]



        Table VIII.G.1--Projected Annual Average Number of HRIs & Fatalities Averted by Demographic Group
                                                    2011-2022
----------------------------------------------------------------------------------------------------------------
                                                                      Averted                         Averted
                                                       HRIs           HRIs(1)       Fatalities      fatalities
                                                             (1)             (2)             (3)             (4)
----------------------------------------------------------------------------------------------------------------
Income decile:
    Less than $29,300...........................         1002.73          651.78           28.66           27.23
    $29,301-$45,000.............................         1061.66          690.08           31.63           30.05
    $45,001-$60,000.............................         1036.34          673.62           30.60           29.07
    $60,001-$75,000.............................         1012.83          658.34           29.56           28.08
    $75,001-$90,500.............................          988.55          642.55           28.70           27.26
    $90,501-$109,200............................          959.71          623.81           27.66           26.27
    $109,201-$131,500...........................          921.58          599.03           26.16           24.86
    $131,501-$164,000...........................          884.51          574.93           24.82           23.58
    $164,001-$224,000...........................          830.46          539.80           22.68           21.54
Age:
    16-24.......................................          882.46          573.60           23.88           22.69
    25-34.......................................          931.32          605.36           26.52           25.19
    35-44.......................................          974.79          633.61           28.89           27.45
    45-54.......................................          980.33          637.21           28.52           27.09
    55-64.......................................          971.74          631.63           27.52           26.14
Sex:
    Male........................................         1191.81          774.68           38.77           36.83
    Female......................................          679.87          441.91           14.30           13.59
Ethnicity & Race:
    Hispanic....................................         1214.52          789.44           39.98           37.98
    Asian/Native American.......................          753.23          489.60           16.49           15.67
    Black/African American......................          879.14          571.44           21.89           20.79
    Other.......................................          907.34          589.77           25.26           23.99
    White (Non-Hispanic)........................          931.37          605.39           26.76           25.42
----------------------------------------------------------------------------------------------------------------


                Table VIII.G.2--Projected Costs Savings of Annual HRI Cases by Demographic Group
                                                   [2011-2022]
----------------------------------------------------------------------------------------------------------------
                                         Pre-standard                # Cases post-standard
                              ------------------------------------------------------------------     Savings
                                    HRIs         Total costs         HRIs         Total costs
                                          (1)              (2)             (3)              (4)              (5)
----------------------------------------------------------------------------------------------------------------
Income decile:
    Less than $29,300........         1002.73    79,296,891.13          350.95    27,753,476.95    51,543,414.18
    $29,301-$45,000..........         1061.66    83,957,134.46          371.58    29,384,917.98    54,572,216.48
    $45,001-$60,000..........         1036.34    81,954,803.54          362.72    28,684,260.32    53,270,543.22
    $60,001-$75,000..........         1012.83    80,095,609.23          354.49    28,033,423.69    52,062,185.54
    $75,001-$90,500..........          988.55    78,175,522.55             346    27,362,026.00    50,813,496.55
    $90,501-$109,200.........          959.71    75,894,826.51           335.9    26,563,307.90    49,331,518.61
    $109,201-$131,500........          921.58    72,879,467.98          322.55    25,507,576.55    47,371,891.43
    $131,501-$164,000........          884.51    69,947,935.31          309.58    24,481,895.98    45,466,039.33
    $164,001-$224,000........          830.46    65,673,607.26          290.66    22,985,683.46    42,687,923.80
Age:
    16-24....................          882.46    69,785,819.26          308.86    24,424,957.66    45,360,861.60
    25-34....................          931.32    73,649,716.92          325.96    25,777,242.76    47,872,474.16
    35-44....................          974.79    77,087,367.99          341.18    26,980,855.58    50,106,512.41
    45-54....................          980.33    77,525,476.73          343.12    27,134,272.72    50,391,204.01
    55-64....................          971.74    76,846,170.94          340.11    26,896,238.91    49,949,932.03
Sex:
    Male.....................         1191.81    94,249,526.61          417.13    32,987,057.53    61,262,469.08
    Female...................          679.87    53,764,799.47          237.96    18,818,114.76    34,946,684.71
Ethnicity & Race:
    Hispanic.................         1214.52    96,045,456.12          425.08    33,615,751.48    62,429,704.64
    Asian/Native American....          753.23    59,566,181.63          263.63    20,848,124.03    38,718,057.60
    Black/African American...          879.14    69,523,270.34           307.7    24,333,223.70    45,190,046.64
    Other....................          907.34    71,753,354.54          317.57    25,113,753.17    46,639,601.37
    White (Non-Hispanic).....          931.37    73,653,670.97          325.98    25,778,824.38    47,874,846.59
----------------------------------------------------------------------------------------------------------------
Source: OSHA calculations using OSHA's Safety Pays Program's ``Estimated Costs of Occupational Injuries and
  Illnesses and Estimated Impact on Company's Profitability Worksheet'' https://www.osha.gov/safetypays/estimator estimator.
Note: OSHA's Safety Pays tool projects how injuries and illnesses may impact company's profitability. The above
  example assumes a 3 percent profit margin for heat prostration (or exhaustion)that cost $79,081 (i.e.,
  includes a direct cost of $37,658 and indirect costs of $41,423). The extent to which the employer pays the
  direct costs depends on the nature of the employer's workers' compensation insurance policy. The employer
  always pays the indirect costs.


[[Page 71001]]

III. Which business owners are impacted by the proposed standard?
    Figure VIII.G.5 shows, for owner-operated firms in industries 
affected by the proposed standard, ownership by demographic group in 
2022. The analysis focuses on owner-operated firms because they are 
recorded in ACS data along with owner characteristics. As such, 
analysis of owner-operated firms cannot be generalized to the entire 
set of affected industries, but sheds light on an important subset of 
these affected industries.
    In general, the distribution of costs (see Section VIII.C., Costs 
of Compliance) are expected to have differential effects on firms in 
industries with different characteristics. In a highly competitive 
product market with many competitor suppliers of nearly identical goods 
or services, there will be limited pass-through of regulatory costs 
assessed on only a subset of firms to consumers in the form of higher 
prices, as individual firms lack the market power to shift prices. If 
firms raised prices, consumers would simply shift consumption to other 
firms not burdened by similar costs (e.g., because they operate in 
temperate climate) that do not raise prices. Were firms earning almost 
zero profits prior to the imposition of these regulatory costs, it 
would be possible that these firms would shut down (and other producers 
would likely expand operations, as demand shifted to them). However, 
evidence on firm revenues in these industries indicates that firms will 
largely be able to bear these costs without shutting down (see Section 
VIII.D., Economic Feasibility).
    However, the assumption of perfectly competitive markets is not 
realized in the actual economy. To the extent that markets are less 
competitive, costs will be passed through in some combination to both 
consumers and firm owners, depending on the price elasticity of demand 
and the price elasticity of supply. In addition, frictions in the labor 
market will dictate how much of the costs are borne by workers, e.g., 
in the form of reduced pay or benefits. The difference in VSL for 
individuals who change and those that maintain the same job can inform 
estimates of the share of costs passed through to firm owners, workers, 
and consumers across industries in scope of this standard (see for 
example, Kniesner et al.'s 2012). Kniesner et al (2012) estimates a job 
switcher-derived VSL between $6.1 million and $10 million (in 2001 
dollars) with a weighted average across job switchers and non-switchers 
is between $4.4 million and $5.5 million; the difference between these 
paired VSL estimates may approximate the average, over the first eight 
post-implementation years, of the portion of per-avoided-fatality 
benefits that accrues to workers without being offset by wage 
reductions. The benefits of the proposed standard could partially 
accrue in the form of increased productivity from workers less affected 
by heat. If firms are currently not offering the privately optimal 
level of workplace heat safety protection (e.g., due to principal-agent 
problems), these productivity gains could even theoretically exceed the 
increased costs borne by the firm. The magnitude of this effect 
determines whether firms are net better-off or worse-off, given both 
costs and increased productivity, as a result of the proposed standard 
(see sections VIII.G.I., and VIII.G.II.).
    The Census Bureau's 2022 American Business Survey (Census Bureau 
and National Center for Science and Engineering Statistics, 2023) 
covers economic and demographic characteristics for businesses and 
business owners by sex, ethnicity, race, and veteran status. Tables 
VIII.G.3. and VIII.G.4., derived from the survey, show that owners from 
historically underrepresented populations (e.g., women and racial 
minorities) tend to be less profitable and have heightened concerns 
about the financial viability of their business (see tables VIII.G.3. 
and VIII.G.4.). These firms command 30-45 percent of the market.\113\ 
Most owners were high-earning, non-Hispanic White males over the age of 
34.
---------------------------------------------------------------------------

    \113\ Tables VIII.G.3. and VIII.G.4. reflect a representative 
sample of all U.S. industries.
---------------------------------------------------------------------------

    Taken together, this evidence suggests that the net benefits of the 
proposed standard for different groups (e.g., high-income and low-
income populations) depend on how market competitiveness, elasticities 
of supply and demand, and the composition of groups affected by the 
standard's costs compare to the distribution of the standard's benefits 
for those groups (as discussed in sections VIII.G.I. and VIII.G.II.).
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IV. Conclusion
    The proposed standard for Heat Injury and Illness Prevention in 
Outdoor and Indoor Work Settings is well-positioned to protect the most 
at-risk workers, across the socioeconomic gradient. In response to the 
advance notice of proposed rulemaking (ANPRM) for Heat Injury and 
Illness Prevention in Outdoor and Indoor Work Settings, members of 
Congress emphasized that ``jobs at the highest risk of heat stress 
illness and death are disproportionately held by workers of color'' and 
occupational risk from heat is the ``greatest for low-income workers'' 
(OSHA-2021-0009-0266; 0270), a concern that was echoed by other 
commenters, including legal experts (see, e.g., OSHA-2021-0009-0524), 
employee representatives (see, e.g., OSHA-2021-0009-0661), and advocacy 
groups (see, e.g., OSHA-2021-0009-0655; 0712). Commenters also called 
for a heat standard that minimizes risks of ``. . . compounding 
language, social service access, and wealth-building barriers'' (OSHA-
2021-0009-0522). The proposed standard reinforces occupational heat 
hazard protections for all workers through the adoption of agile and 
culturally attunable provisions. For example, the provisions:
     Requiring training on occupational heat-related risks and 
protections covered by this standard (e.g., rest breaks, water) to 
employees upon hire and each year can enhance knowledge of heat safe 
work practices, reducing risk of HRIs among less experienced or 
vulnerable workers;
     Requiring the provision of training in a language and 
literacy level appropriate for staff along with the opportunities for 
questions and answers ensures heat protections (e.g., paid rest breaks, 
cool drinking water) are understood and accessible to all; and
     Requiring an acclimatization protocol along with paid rest 
breaks that include adequate drinking water, shade (or air 
conditioning), and medical attention (if necessary) at initial and high 
heat triggers foster non-exploitive treatment of non-salaried 
vulnerable workers (e.g., farmworkers).
    The provisions have economic effects extending beyond the direct 
benefits to workers in affected industries. Heat is the leading cause 
of weather-related deaths, estimated to cost the U.S. $1 billion in 
excess health care costs each year with a projection to potentially 
reach $14.5 trillion in economic damages via factors impacting the 
economic production over the next fifty years (Woolf et al., 2023; 
Deloitte, 2022). The standard is projected to reduce occupational heat-
induced deaths which can offset the estimated health costs due to 
weather. The proposed standard is primed for responsiveness to workers 
of all levels of social vulnerability while counteracting the broader 
economic costs of extreme temperatures.

H. Appendix A. Description of the Cost Savings Approach

I. Introduction
    This appendix details the underlying calculations of the potential 
cost savings from the proposed standard as a result of requiring 
employers to provide employees if-needed or scheduled rest breaks. The 
best available evidence indicates that when employees are exposed to 
heat and are not allowed to take rest breaks or adjust their work 
hours, they must pace themselves (i.e., work more slowly) to counteract 
the effects of heat exposure. OSHA has preliminarily determined that 
when employees are offered rest breaks, cost savings will accrue to 
employers currently noncompliant with the rest break requirement 
because employees will work more efficiently during the work time not 
spent on rest breaks (i.e., pace less), effectively replacing pacing 
with if-needed or scheduled rest breaks. First, for the three groups 
defined below, OSHA estimated the percentage of productivity loss at 
the initial heat trigger using the Heat Index (HI) option (i.e., (HI) 
at or above 80 [deg]F) and above the high heat trigger (i.e., HI at or 
above 90 [deg]F). These estimates were then translated to equivalent 
lost minutes of work time in an 8-hour work shift.
    When working in hot conditions, OSHA assumes that employees can 
take three different measures to avoid overheating:
    (1) Measure #1: Employees pace themselves; for example, an employee 
shovels gravel at a slower pace in hot conditions than they would in 
cooler conditions.
    (2) Measure #2: Employees take rest breaks if needed; for example, 
an employee leans on their shovel for a few minutes at a time whenever 
they feel overwhelmed by the heat, which they otherwise would not do in 
cooler conditions.
    (3) Measure #3: Employees take scheduled rest breaks; for example, 
twice a day, for 15 minutes at a time, an employee sits in a cool or 
shaded area to drink water and recover from the heat.
    Depending on what is allowed by their employers, employees can take 
multiple measures to avoid overheating (i.e., they are not mutually 
exclusive). Three groups of employees were defined based on possible 
combinations of measures:
    (1) Group #1: Employees who only use pacing (Measure #1). These 
employees do not take any rest breaks, possibly because their employer 
does not allow them to take breaks.
    (2) Group #2: Employees who take rest breaks if needed (Measure #2) 
and use pacing (Measure #1). These employees are allowed to take brief, 
unscheduled breaks by their employer. However, these rest breaks may 
not be long or frequent enough to allow for a full recovery from the 
heat exposure (return to normal body temperature of 98.6[deg]F 
(37[deg]C)). Therefore, these employees still display residual pacing 
while they work.
    (3) Group #3: Employees who take scheduled rest breaks (Measure 
#3), may take rest breaks if needed (Measure #2), and use pacing 
(Measure #1). These employees are allowed to take scheduled rest 
breaks, which may allow them to rehydrate and rest in a cool or shaded 
area, as well as rest breaks if needed. However, these rest breaks do 
not entirely eliminate productivity loss, as these employees also 
display residual pacing, though it is expected to be to a lesser extent 
than employees in Group #2.
II. Primary Approach
    This section describes the method that OSHA used to estimate labor 
productivity losses that result from pacing due to heat exposure. 
First, the general approach is summarized, next the general assumptions 
of the analysis are outlined, and then the calculations are detailed 
for Groups 1, 2, and 3.
A. Summary of Approach
    For the primary approach, OSHA searched for studies that examined 
how working in hot vs. cool conditions affect employee productivity. 
Eastern Research Group (ERG) performed several literature searches 
(ERG, 2022a; ERG, 2022b; ERG, 2022c) and identified a total of 71 
unique studies that could inform the relationship between heat and 
various outcomes (e.g., labor productivity, heat strain). OSHA also 
reviewed the reference lists of these studies and identified an 
additional 37 studies that were potentially relevant to this topic. 
This yielded a total of 108 studies considered for inclusion for the 
purposes of estimating the impact of rest breaks on labor productivity 
at the initial heat and high heat triggers. Generally, studies were 
excluded if they did not meet the inclusion criteria listed below (more 
detailed reasons for exclusion are listed in table VIII.H.A.3.).

[[Page 71007]]

     Measured labor productivity over a range of temperatures, 
so that a comparison could be made between a cool (REF) condition below 
the initial heat trigger (i.e., HI at or above 80 [deg]F), and a HOT 
condition(s) above the high heat trigger (i.e., HI at or above 90 
[deg]F).
     Provided enough information on weather conditions so that 
HI could be estimated, even if based on historical weather data.
     Collected labor productivity data.
     Reported labor productivity as output per worker, per 
hour, or per day.
     Provided information as to whether breaks were offered, 
and if so, how long and frequent the breaks were.
    Once studies were identified for inclusion, each included study was 
evaluated for four key pieces of information:
    (1) Which measure(s) employees took to avoid overheating (Measures 
#1, #2, and/or #3), allowing the assignment of employees to Groups #1, 
#2, or #3.
    (2) Weather data that describe the cool condition, or the referent 
(REF) condition. This could be when the HI was lowest, or when output 
was highest (i.e., 100% productivity). The HI was calculated based on 
the ambient or dry bulb temperature (Ta or Td, respectively) and the 
relative humidity (RH).
    (3) Weather data that describe the HOT condition(s). This could be 
when the HI was highest, or at which output was lowest (i.e., 50% lower 
output means 50% productivity). Again, HI was calculated to ensure that 
the HOT condition(s) exceeded both the initial and high heat triggers.
    (4) Labor productivity at both the REF and HOT conditions, so that 
the loss in labor productivity (%) could be divided by the difference 
in HI ([deg]F) and expressed as a rate of lost labor productivity per 
1[deg]F HI.
    After calculating the rate of labor productivity loss per 1 [deg]F 
HI, OSHA calculated the (cumulative) labor productivity loss as a 
percentage relative to the REF condition at the initial heat trigger 
(HI of 80 [deg]F) and high heat trigger (HI of 90 [deg]F). This labor 
productivity loss was then translated into equivalent minutes of lost 
work time by multiplying by an 8-hour work shift (480 minutes).

                                                             Table VIII.H.A.1--Summary Table
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                             Productivity
                                                                                              loss per 1     Productivity loss at   Productivity loss at
       Group                  Study                 HI at REF              HI at HOT           [deg]F HI     initial heat trigger    high heat  trigger
                                                                                             above REF (%)
--------------------------------------------------------------------------------------------------------------------------------------------------------
1..................  LoPalo, 2023..........  66.1 [deg]F...........  105.2 [deg]F.........            0.35  23.4 min.............  40.2 min
                                                                                                            (4.9%)...............  (8.4%)
                     Foster et al., 2021...  76.8 [deg]F...........  161.4 [deg]F.........            0.73  11.3 min.............  46.4 min
                                                                                                            (2.4%)...............  (9.7%)
                     Hanna, 2004...........  79.2 [deg]F...........  122.3 [deg]F.........            0.86  3.3 min..............  44.5 min
                                                                                                            (0.7%)...............  (9.3%)
                     Somanathan et al.,      63.4-82 [deg]F........  90-105.8 [deg]F......            0.29  18.0 min.............  31.3 min
                      2021.                                                                                 (3.8%)...............  (6.5)
                    ------------------------------------------------------------------------------------------------------------------------------------
                                                       Group Mean: 0.56%                                    14.0 min.............  40.6 min
--------------------------------------------------------------------------------------------------------------------------------------------------------
2..................  Ioannou et al., 2017..  72.1-75.6 [deg]F......  96.9-103.1 [deg]F....            0.73  22.3 min.............  57.4 min
                                                                                                            (4.6%)...............  (12.0%)
                     Sahu et al., 2013.....  85.5 [deg]F...........  116.6 [deg]F.........            1.00  0 min................  21.6 min
                                                                                                            (0%).................  (4.2%)
                    ------------------------------------------------------------------------------------------------------------------------------------
                                                       Group Mean: 0.865%                                   11.2 min.............  39.5 min
--------------------------------------------------------------------------------------------------------------------------------------------------------
3..................  Dally et al., 2018....  88.3 [deg]F...........  102.6 [deg]F.........            1.03  0 min................  8.4 min
                                                                                                            (0%).................  (1.8%)
                    ------------------------------------------------------------------------------------------------------------------------------------
                                                       Group Mean: 1.03%                                    0 min................  8.4 min
--------------------------------------------------------------------------------------------------------------------------------------------------------

B. General Assumptions
    When estimating labor productivity loss in each study, OSHA made 
the following assumptions:
    a. Unless otherwise specified, productivity at or below the REF 
condition is 100%.
    b. Above the REF condition, the relationship between HI and labor 
productivity loss is linear, i.e., the rate of loss (per 1 [deg]F HI) 
is a constant. Therefore, the productivity loss function for any firm 
can be fully characterized by two parameters: the REF condition and the 
rate of loss.
    c. Employees in Group 2 are allowed to take up to 10 minutes of 
rest breaks if needed (with 2-4 minutes of travel time to/from break 
areas).
    d. Employees in Group 3 are allowed to take 30 minutes of scheduled 
rest breaks, along with 5 minutes of rest breaks if needed (with 2-4 
minutes of travel time to/from break areas for each break).
    e. An employee's expected productivity loss from pacing, given a 
specific temperature and the employer's rest break policy, can be 
estimated by the average productivity loss measured in studies where 
that rest break policy is in effect. In other words, the set of studies 
with each group fully characterizes the productivity loss that would be 
experienced by employees at a firm that offered the associated rest 
break policy, regardless of what rest break policy it currently offers.
    f. An employee's expected productivity gains from taking new or 
newly scheduled rest breaks (versus not taking breaks or taking only 
if-needed breaks) can be estimated by differences in productivity 
losses due to pacing, as measured at the initial temperature (i.e., 
trigger) at which the rest break policy goes into effect.\114\
---------------------------------------------------------------------------

    \114\ All else equal, using the initial temperature (i.e., 
trigger) rather than the temperature inputs used elsewhere in this 
PEA will yield underestimates of the effects reported in table 
VIII.H.A.1. When subsequently performing subtraction (for expressing 
productivity differences across Groups), there is ambiguity about 
the direction of misestimation--because the difference between two 
underestimated amounts may be over- or underestimated.

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[[Page 71008]]

C. Productivity Loss Estimates by Group
I. Group 1 Studies
    LoPalo (2023) assessed the effects of temperature on the 
productivity of 9,000 Demographic and Health Surveys interviewers in 46 
countries. Interviewers were paid an hourly wage and were assumed to be 
acclimatized because they were ``recruited within a region of a country 
as much as possible so that the interviewer [did] not seem foreign to 
the respondent'' (p. 197). The author concluded that ``high 
temperatures are detrimental to productivity, with interviewers 
experiencing a 13.6 percent loss in interviews per hour on days over 85 
[deg]F wet bulb'' (pp. 208-209).
    The author clarifies, ``more specifically, I estimate the effect of 
daily average wet bulb temperature falling into a certain bin on my 
outcome variable of interest, relative to an excluded bin of 50-60 
[deg]F (50-60 [deg]F wet bulb corresponds with a median dry bulb 
temperature of 66 [deg]F in my sample)'' (p. 205). Thus, a dry bulb 
temperature (Td) of 66 [deg]F was selected for the calculation of the 
heat index (HI) for the REF condition. Per Figure 1 (p. 203), in this 
sample, a Td of 66 [deg]F yields a wet bulb temperature of 55 [deg]F 
when RH is 80%. Therefore, OSHA used 80% RH for the calculation of HI. 
A Td of 66 [deg]F and 80% RH yielded an HI of 66.1[deg]F for the REF 
condition.
    The author created bins of both Td and wet bulb temperature; the 
highest bin for Td was '>95 [deg]F''. Therefore, a Td of 95 [deg]F was 
used to calculate the HI for the HOT condition. The author states, 
``the highest daily average wet bulb temperature in my sample is 87.7 
[deg]F, while the highest daily average dry bulb temperature is 102.6 
[deg]F'' (p. 206). Per Figure 1 (p. 203), in this sample, a Td of 102.6 
[deg]F yields a wet bulb temperature of 87.7 [deg]F when RH is 50%. 
Therefore, OSHA used 50% RH for the calculation of HI. A Td of 95 
[deg]F and 50% RH yielded an HI of 105.2 [deg]F for the HOT condition.
    Finally, the productivity loss from the REF condition to the HOT 
condition was estimated. In table 2. (p. 209), the author provides a 
regression estimate for each bin of dry bulb temperature to indicate 
its effect on the number of interviews completed per hour. The estimate 
in Column 2 (-0.135, or 13.5% loss) accounted for both Td and high 
humidity and most closely matched the estimate in Column 4 for wet bulb 
temperature (-0.136, or 13.6% loss). Therefore, OSHA selected the 
estimate for Td and high humidity, which yielded a rate of productivity 
loss of 0.35% per 1 [deg]F HI.
    Relative to the REF condition (66.1 [deg]F HI), the productivity 
loss at the initial heat trigger (80 [deg]F HI) is 4.87%. For an 8-hour 
work shift (480 minutes), this translates to a loss of 23.4 minutes.
    Relative to the REF condition (66.1 [deg]F HI), the productivity 
loss at the high heat trigger (90 [deg]F HI) is 8.37%. For an 8-hour 
work shift (480 minutes), this translates to a loss of 40.2 minutes.
    Foster et al. (2021) assessed the effects of temperature on 
physical work capacity (PWC) of 40 unacclimatized young adult males at 
22 different combinations of air temperature (Ta) and relative humidity 
(RH). First, the authors measured maximal PWC (i.e., 100% productivity) 
at a Ta of 59 [deg]F and RH of 50%. Then, the authors assessed PWC 
under various conditions, with Ta ranging from 77 [deg]F to 122 [deg]F 
and RH ranging from 20% to 80%.
    To determine an appropriate REF condition, OSHA plotted the low-
clothing coverage estimates from table 2. (p. 1222) and found a 
sigmoidal curve. That is, as Ta increased from 59 [deg]F to 77 [deg]F, 
the curve was nearly flat, indicating minimal productivity decline. 
Then, at a Ta of 77 [deg]F (and 50% RH), productivity began to decline 
in a nearly perfect linear fashion (R\2\ = 0.99). Therefore, the REF 
condition was selected as a Ta of 77 [deg]F and RH of 50%. This 
combination yielded an HI of 76.8 [deg]F for the REF condition.
    The combination of temperature and humidity that corresponded the 
greatest productivity loss (66%) along the linear portion of the curve 
was a Ta of 104 [deg]F and RH of 70%. This combination yielded an HI of 
161.4 [deg]F for the HOT condition.
    The productivity loss from the REF condition to the HOT condition 
was estimated. In table 2. (p. 1222), the authors reported that at the 
REF condition (Ta 77 [deg]F, RH 50%), PWC was 96%, and at the HOT 
condition (Ta 104 [deg]F, RH 70%), PWC was 34%. This yielded a rate of 
productivity loss of 0.73% per 1 [deg]F HI.
    Relative to the REF condition (76.8 [deg]F HI), the productivity 
loss at the initial heat trigger (80 [deg]F HI) is 2.35%. For an 8-hour 
work shift (480 minutes), this translates to a loss of 11.3 minutes.
    Relative to the REF condition (76.8 [deg]F HI), the productivity 
loss at the high heat trigger (90 [deg]F HI) is 9.67%. For an 8-hour 
work shift (480 minutes), this translates to a loss of 46.4 minutes.
    Hanna (2004) assessed the effects of temperature on the 
productivity of two electrical journeymen in a climatic chamber at 
various combinations of Ta (ranging from -10 [deg]F to 110 [deg]F, in 
increments of 10 [deg]F) and RH (ranging from 40% to 80%, in increments 
of 10%). The journeymen were assessed for their performance of a 
routine work task (installing duplex receptacles) over a total of 6 
days of testing. The author stated that ``for the purpose of this 
study, the average number of receptacles installed in one hour during 
the first day of work measurement at 70 [deg]F and 60% RH is expressed 
as 100% productivity.''
    However, per Chart 2-1 (p. 15), productivity clearly only began to 
decline at a Ta of 80 [deg]F and RH of 30%. Therefore, the REF 
condition was selected as a Taof 80 [deg]F and RH of 30%. This 
combination yielded an HI of 79.2 [deg]F for the REF condition.
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[[Page 71009]]


    According to table 2.3. (p. 11), the combination of temperature and 
humidity that corresponded the greatest productivity loss (38%) was a 
Ta of 110 [deg]F and RH of 30%. This combination yielded an HI of 122.3 
[deg]F for the HOT condition.
    The productivity loss from the REF condition to the HOT condition 
was estimated. In table 2.3. (p. 11), the authors reported that at the 
REF condition (Ta 80 [deg]F, RH 30%), productivity was 99%, and at the 
HOT condition (Ta 110 [deg]F, RH 30%), productivity was 62%. This 
yielded a rate of productivity loss of 0.86% per 1 [deg]F HI.
[GRAPHIC] [TIFF OMITTED] TP30AU24.014

    Relative to the REF condition (79.2 [deg]F HI), the productivity 
loss at the initial heat trigger (80 [deg]F HI) is 0.69%. For an 8-hour 
work shift (480 minutes), this translates to a loss of 3.3 minutes.
[GRAPHIC] [TIFF OMITTED] TP30AU24.015

    Relative to the REF condition (79.2 [deg]F HI), the productivity 
loss at the high heat trigger (90 [deg]F HI) is 9.27%. For an 8-hour 
work shift (480 minutes), this translates to a loss of 44.5 minutes.
[GRAPHIC] [TIFF OMITTED] TP30AU24.016

    Somanathan et al. (2021) assessed the productivity of indoor 
workers in cloth-weaving, garment-sewing, and steel mill industries in 
India. OSHA only analyzed garment-sewing workers, who were ``paid 
monthly wages'' (p. 1803), and their productivity was assessed as 
``actual hourly output, when controlled for the target [output]'' from 
``103 sewing lines over a period of 730 days during the calendar years 
of 2012 and 2013'' (p. 1804). OSHA excluded workers from the cloth 
weaving industry because productivity was not reported for the full 
range of temperatures (Figure 1C, p. 1808). OSHA also excluded certain 
garment plants and the steel mill, as these facilities were climate-
controlled (p. 1806), and workers experienced limited variations in 
temperature.
    The authors reported productivity as a function of daily maximum 
temperature (Ta) in Figure 1 (p. 1808). Temperature data came from 
``recordings from public weather stations within the cities where . . . 
garment-sewing factories are located'' (p. 1806), i.e., the National 
Capital Region (NCR), Hyderabad, and Chhindwara. The authors created 
temperature bins for each industry, as well as the equivalent bins 
based on wet-bulb temperature (WBT), which accounts for both Ta and RH 
(appendix, p. 3).

----------------------------------------------------------------------------------------------------------------
                                      Garment-sewing (inside NCR)             Garment-sewing (outside NCR)
                                --------------------------------------------------------------------------------
                                                      Equivalent WBT
                                  Temperature bin          bin          Temperature bin     Equivalent WBT bin
----------------------------------------------------------------------------------------------------------------
REF............................  <19 [deg]C.......  <15 [deg]C.......  <27 [deg]C.......  <23 [deg]C.
HOT............................  >33 [deg]C.......  >25.5 [deg]C.....  >33 [deg]C.......  >29 [deg]C.
Max............................  >35 [deg]C.......  >27 [deg]C.......  >35 [deg]C.......  >31 [deg]C.
----------------------------------------------------------------------------------------------------------------

    To calculate the HI for the REF condition in the garment-sewing 
industry, the Ta for the lowest bin was used and RH was calculated 
using the equation below (provided by the authors). Inside the NCR, the 
Ta was 66.2 [deg]F (19 [deg]C) and RH was calculated at 18%, yielding 
an HI of 63.4 [deg]F for the REF condition. Outside the NCR, the Ta was 
80.6 [deg]F (27 [deg]C) and RH was calculated as 56%, yielding an HI of 
82 [deg]F for the REF condition.
[GRAPHIC] [TIFF OMITTED] TP30AU24.017

    To calculate the HI for the HOT condition in the garment-sewing 
industry, the Ta for the second highest bin was used because this is 
where productivity losses reached a maximum and plateaued (Figure 1A-B, 
p. 1808). RH was again calculated using the equation above. Inside the 
NCR, the Ta was 91.4 [deg]F (33 [deg]C) and RH was calculated at 31%, 
yielding an HI of 90 [deg]F for the HOT condition. Outside the NCR, the 
Ta was also 91.4 [deg]F (33 [deg]C) and

[[Page 71010]]

RH was calculated as 64%, yielding an HI of 105.8 [deg]F for the HOT 
condition.
    The productivity losses from the REF conditions to the HOT 
conditions were estimated using data from Figure A.3 (appendix, p. 6). 
For garment workers inside the NCR, the authors reported that at the 
HOT condition, there was a 12% loss in productivity, which yields a 
rate of 0.45% per 1 [deg]F HI. Outside the NCR, the authors reported 
that at the HOT condition, there was a 3% loss in productivity, which 
yields a rate of 0.13% per 1 [deg]F HI.
[GRAPHIC] [TIFF OMITTED] TP30AU24.018

    Relative to the REF condition, inside the NCR, productivity loss at 
the initial heat trigger (80 [deg]F HI) was 7.49%. For an 8-hour work 
shift (480 minutes), this translates to a loss of 35.9 minutes. Outside 
the NCR, productivity loss is assumed to be 0% because the REF (82 
[deg]F HI) was above the initial heat trigger. The mean loss is 18.0 
minutes.
[GRAPHIC] [TIFF OMITTED] TP30AU24.019

    Relative to the REF condition, inside the NCR, productivity loss at 
the high heat trigger (90 [deg]F HI) was 12.0%. For an 8-hour work 
shift (480 minutes), this translates to a loss of 57.6 minutes. Outside 
the NCR, productivity loss at the high heat trigger was 1.0%, or a loss 
of 4.8 minutes. The mean loss is 31.3 minutes.
[GRAPHIC] [TIFF OMITTED] TP30AU24.020

    Ioannou et al. (2017) assessed the effects of temperature on the 
productivity of 7 grape-picking workers in Cyprus over 4 study days: 
two in the summer (August 17-18, 2016) and two in the autumn (October 
11-12, 2016). The workers were ``healthy and heat-acclimatized'' (p. 
332), and their pay system was not specified. They were ``officially 
not provided with any breaks other than the lunch break'' (p. 338) but 
did take ``irregular work breaks . . . defined as any unprescribed work 
cessation determined by workers' own judgment, and not based on 
specific time intervals or instructions'' (p. 333). Productivity was 
assessed as ``the number of boxes full of grapes picked by the entire 
group in each hour divided by the number of workers'' (p. 333).
    The authors reported hourly productivity as a function of wet bulb 
globe temperature (WBGT). The calculation of WBGT was based on weather 
data (including Ta and RH) from the Paphos International Airport in 
Cyprus. OSHA accessed the same historical weather data 
(wunderground.com) for the 4 study days and calculated the hourly HI 
(based on Ta and RH) for each study day. On October 11 and 12, the 
highest HI was still below the high heat trigger (83.8 [deg]F and 85.6 
[deg]F, respectively) and would have required extrapolation to estimate 
the rate of productivity loss. Therefore, only weather and productivity 
data from August 17 and 18 was considered. The lowest HI for each day 
served as the REF condition for that day; the REF HI for August 17 was 
75.6 [deg]F (based on a Ta of 75 [deg]F and

[[Page 71011]]

73% RH), and the REF HI for August 18 was 72.1 [deg]F (based on a Ta of 
72 [deg]F and 69% RH).
    The highest HI for each day served as the HOT condition. The HOT HI 
for August 17 was 96.9 [deg]F (based on a Ta of 86 [deg]F and 74% RH), 
and the HOT HI for August 18 was 103.1 [deg]F (based on a Ta of 88 
[deg]F and 75% RH).
    The productivity loss from the REF condition to the HOT condition 
for the 2 study days (August 17-18) was estimated by plotting the 
hourly HI against the productivity data (boxes per hour) in Figure 6 
(p. 337). The rate of productivity loss was 0.65% per 1 [deg]F HI for 
August 17, and 0.81% per 1 [deg]F HI on August 18, which yielded a mean 
rate of 0.73% per 1 [deg]F HI.
[GRAPHIC] [TIFF OMITTED] TP30AU24.021

    Relative to the REF conditions, the productivity loss at the 
initial heat trigger (80 [deg]F HI) was 2.87% for August 17 and 6.40% 
for August 18. For an 8-hour work shift (480 minutes), this translates 
to a loss of 13.8 and 30.7 minutes, respectively, and a mean loss of 
22.3 minutes.
[GRAPHIC] [TIFF OMITTED] TP30AU24.022

    Relative to the REF conditions, the productivity loss at the high 
heat trigger (90 [deg]F HI) was 9.40% for August 17 and 14.5% for 
August 18. For an 8-hour work shift (480 minutes), this translates to a 
loss of 45.1 and 69.6 minutes, respectively, and a mean loss of 57.4 
minutes.
[GRAPHIC] [TIFF OMITTED] TP30AU24.023

    Sahu et al. (2013) assessed the effects of temperature on the 
productivity of 48 male rice harvesters in Bengal, India from April to 
June in 2011. Workers were paid on a piece-rate system, and their 
acclimatization status was not specified. They were allowed to take 
``small breaks (3-6 min) between work tasks [that] were included as 
part of the normal work time management'' (p. 426). Productivity was 
assessed as the ``hourly number of bundles divided by the number of 
workers to calculate the average hourly productivity per worker'' (p. 
426). The authors measured both Ta and WBGT in the farm fields and 
estimated the relationship between them (Figure 1, p. 427).
    The authors only reported productivity as a function of WBGT 
(Figure 4, p. 428). First, the WBGT when

[[Page 71012]]

productivity was highest (25.7 [deg]C) and lowest (30.9 [deg]C) was 
identified. Then the regression equation from Figure 1 was used to 
estimate Ta based on WBGT. Finally, to estimate RH, historical weather 
data ``from the nearby weather station at Kolkata Dum-Dum airport'' (p. 
426) was used, upon which the authors had also relied. OSHA identified 
the days from April through June 2011 that matched the Ta for highest 
productivity (80.6 [deg]F) and lowest productivity (97.4 [deg]F) at 6 
a.m. (when Ta was measured for the first hour of work), and then used 
the corresponding level of RH. This yielded an HI of 85.5 [deg]F for 
the REF condition (based on a Ta of 80.6 [deg]F and 80% RH), and an HI 
of 116.6 [deg]F for the HOT condition (based on a Ta of 97.4 [deg]F and 
56% RH).
    OSHA estimated productivity loss from the REF condition to the HOT 
condition based on the productivity data (rice bundles per hour) for 
the first hour of work in Figure 4 (p. 428). Workers harvested 92 rice 
bundles per hour at the REF condition (i.e., 100% productivity), and 
63.8 bundles per hour at the HOT condition (i.e., 69% productivity). 
This yielded a rate of productivity loss of 1.00% per 1 [deg]F HI.
[GRAPHIC] [TIFF OMITTED] TP30AU24.024

    The productivity loss at the initial heat trigger (80 [deg]F HI) is 
assumed to be 0% because the REF condition, at which productivity was 
assumed to be 100%, is higher than the initial heat trigger.
    Relative to the REF condition (85.5 [deg]F HI), the productivity 
loss at the high heat trigger (90 [deg]F HI) is 4.50%. For an 8-hour 
work shift (480 minutes), this translates to a loss of 21.6 minutes.
[GRAPHIC] [TIFF OMITTED] TP30AU24.025

III. Group 3 Studies
    Dally et al. (2018) assessed the effects of temperature on the 
productivity of 4,095 sugarcane cutters in Guatemala from November 2015 
to May 2016. Workers received ``a base wage regardless of the amount of 
sugarcane harvested'' (p. 3) and were acclimatized (i.e., they 
completed a ``one week acclimatization period in November'' (p. 3). 
They worked a ``ten-hour shift (p. 3) and were allowed to ``take three 
20-minute breaks and one 60-minute lunch break in the provided shade 
during the work shift'' (p. 4). The authors reported daily productivity 
as the ``average daily tons cut per workday'' (p. 4). The authors 
collected data on Ta, RH, and WBGT using the Cengica[ntilde]a weather 
station located close to the sugarcane fields.
    Using historical weather data (collected at 15-minute intervals) 
from the Cengica[ntilde]a weather station, Ta and RH were 
used to calculate HI for each day of the harvest season. OSHA 
identified the days with the highest and lowest HI based on the 75th 
percentile of each day, which provided the range of temperatures that 
most closely corresponded to the extreme values of daily productivity 
(as compared with mean HI or max HI). This yielded an HI of 88.3 [deg]F 
for the REF condition and an HI of 102.6 [deg]F for the HOT condition.
    The productivity loss from the REF condition to the HOT condition 
was estimated based on the productivity data (tons of sugarcane per 
day) in Figure 2 (p. 7). Workers harvested 6.0 tons per day at the REF 
condition (i.e., 100% productivity), and 5.42 tons per day at the HOT 
condition (i.e., 90.3% productivity). This yielded a rate of 
productivity loss of 0.68% per 1 [deg]F HI.
[GRAPHIC] [TIFF OMITTED] TP30AU24.026

    However, the sugarcane cutters were given a total of 60 minutes of 
rest breaks (3x20 minutes) over the course of a 9-hour work shift, 
while the proposed rule would require a total of 35 minutes of rest 
breaks (2x15-minute scheduled rest breaks and 5 minutes of rest breaks 
if needed) over the course of an 8-hour work shift at the high heat 
trigger. Therefore, OSHA assumed that the rate of productivity loss 
should be multiplied by 1.52, or the ratio of the percentages of the 
work shift spent in breaks for these two scenarios. This yielded an 
adjusted rate of productivity loss of 1.03% per 1 [deg]F HI.
[GRAPHIC] [TIFF OMITTED] TP30AU24.027


[[Page 71013]]


    Relative to the REF condition (88.3 [deg]F HI), the productivity 
loss at the high heat trigger (90 [deg]F HI) is 1.75%. For an 8-hour 
work shift (480 minutes), this translates to a loss of 8.4 minutes.
[GRAPHIC] [TIFF OMITTED] TP30AU24.028

III. Findings of Primary Approach
    This appendix presents OSHA's estimates of the labor productivity 
loss resulting from pacing (i.e., working slowly during the work time 
not spent on breaks) when the heat index is equal to the initial and 
high heat triggers. This appendix also presents OSHA's estimates of the 
decrease in pacing with the introduction of if-needed and scheduled 
breaks--the findings of the primary approach suggest that employees 
pace less (i.e., work more efficiently) with if-needed rest breaks, and 
that scheduled rest breaks further reduce pacing (i.e., employees 
become even more efficient). These estimated labor productivity losses 
from pacing were translated to and presented as equivalent lost minutes 
of work time in an 8-hour work shift.
    At the initial heat trigger, employees given if-needed rest breaks 
are estimated to pace less (i.e., work more efficiently) by an average 
of 2.8 minutes (per 8-hour shift) compared to those not given if-needed 
rest breaks. At the high heat trigger, employees given both scheduled 
and if-needed rest breaks are estimated to pace less (i.e., work more 
efficiently) by an average of 32.2 minutes (per 8-hour shift) compared 
to those not given neither if-needed nor scheduled rest breaks and by 
an average of 31.1 minutes (per 8-hour shift) compared to those given 
only if-needed rest breaks.
IV. Alternate Approaches Under Consideration
    OSHA has preliminarily determined that the assumptions made in the 
primary approach are plausible and appropriate. However, OSHA 
recognizes that the limited scope of available evidence affects the 
extent to which these key assumptions can be tested. For example, none 
of the available studies directly compared rest break policies in the 
same setting, so the estimates of cost savings are based on differences 
in productivity losses across settings. OSHA is considering alternate 
approaches with varying assumptions, such as the extent to which 
productivity losses in one setting, given a certain rest break policy, 
may be representative of such losses in other settings.
    One alternate approach modifies some of the key assumptions made in 
the primary approach, while still relying on the same set of studies. 
Specifically, this approach retains Assumptions (a) through (d) and 
Assumption (f), but it replaces Assumption (e) with the following:
    e.1. An employee's expected productivity loss from pacing, given a 
specific temperature and the employer's break policy, is estimated by 
taking the average REF condition observed in studies where that break 
policy is in effect, along with the average productivity loss per 
degree observed across all studies.
    e.2. An employee's expected productivity gains from taking rest 
breaks do not exceed the productivity losses that are observed when 
they work at a slower pace and do not take rest breaks. In other words, 
if a rest break policy yielded an overall net increase in productivity, 
employers would already offer these rest breaks. Gains can be estimated 
by differences in productivity losses due to pacing, as measured at the 
initial temperature (i.e., trigger) at which the rest break policy goes 
into effect.
    Compared with those of the primary approach, the above alternate 
assumptions are more relaxed in some ways and stronger in others. In 
particular, the assumption that productivity losses per degree are 
estimated in a pooled fashion, but REF conditions are not, implies that 
all productivity gains associated from reduced pacing come in the form 
of a shift in the productivity loss function. This assumption addresses 
the potential concern that differences in work conditions other than 
temperature (such as sun exposure or work demands) limit the 
applicability of any findings on productivity loss to other work 
settings.
    Under this alternate approach, OSHA expects that productivity 
losses at the initial and high heat triggers will be larger for 
employees in Group 1, and they will be smaller for employees in Groups 
2 and 3 (see table VIII.H.A.2).\115\ This means that under these 
assumptions, even greater cost savings could accrue to employers if 
they offered rest breaks if needed at the initial heat trigger, and 
scheduled rest breaks as well as if-needed rest breaks at the high heat 
trigger. OSHA welcomes feedback on this alternate approach and has not 
yet calculated how it would impact the total cost of the proposed 
standard.
---------------------------------------------------------------------------

    \115\ Not reflected in table VIII.H.A.2 is the possibility that 
the exclusion criteria listed in table VIII.H.A.3 may need to be 
reconsidered if the cost savings estimation approach is revised.

                              Table VIII.H.A.2--Summary Table of Alternate Approach
----------------------------------------------------------------------------------------------------------------
                                                       Productivity loss
                                                        per 1[deg]F HI     Productivity loss   Productivity loss
              Group               HI at REF (average   above REF (pooled    at initial heat      at high heat
                                     within group)      average for all     trigger (min.)      trigger (min.)
                                                          groups) (%)
----------------------------------------------------------------------------------------------------------------
1...............................  73.7 [deg]F.......                0.71                21.5                55.6
2...............................  79.7 [deg]F.......                0.71                 1.0                35.1
3...............................  88.3 [deg]F.......                0.71                   0                5.8
----------------------------------------------------------------------------------------------------------------
The average HI at REF uses the midpoint for each study in cases where a range was specified. The average
  productivity loss is the pooled average from table VIII.H.A.1.


[[Page 71014]]

    In both the primary approach and the secondary approach 
(immediately above), the REF condition--which is, loosely, the minimum 
temperature at which heat begins to cause productivity loss--is assumed 
to differ across Groups. The two estimation approaches diverge in that 
the per-degree rate of loss in conditions above REF is always 0.71% in 
the secondary approach but is allowed to differ by Group in the 
primary.\116\ A tertiary approach would reverse which parameter is 
estimated in a pooled manner; the REF condition would be the same 
across Groups, while the per-degree rate of loss would differ. As shown 
in table VIII.H.A.1., however, the per-degree rate of loss is estimated 
to increase with amounts of rest, so this approach would yield an 
estimate of productivity-related costs, rather than cost savings. 
Although this result is not plausible, it illustrates some of the 
uncertainties about data and quantitative methods used in this 
appendix.
---------------------------------------------------------------------------

    \116\ However, allowing heterogeneity in the reference 
temperature has support in the literature; see Heutel et al. (2021).
---------------------------------------------------------------------------

    A pooled regression could address some of these challenges by 
producing a single estimate representing the relationship between 
temperature and productivity loss that does not differ by break policy, 
then separately producing estimates as to how each rest break policy 
might improve productivity. OSHA is considering an additional alternate 
approach that would incorporate regression analysis and might, as part 
of such analysis, relax the assumption regarding the linearity of the 
relationship between temperature and productivity loss. That is, a 
nonlinear specification could address the potential concern that 
productivity losses may become increasingly severe as the temperature 
exceeds the initial heat and high heat triggers.
    In sum, OSHA welcomes feedback on the primary cost savings approach 
and the alternate approaches. OSHA also welcomes suggestions for other 
approaches to estimate cost savings related to the provision of rest 
breaks.

  Table VIII.H.A.3--Studies Excluded From Pacing Estimates, Grouped by
                          Reason for Exclusion
------------------------------------------------------------------------
     Study, listed as author(s) and year          Study identified by
------------------------------------------------------------------------
Did not measure temperature conditions
 (n=2):
    Hostler et al., 2016....................  ERG 2022b.
    O'Neill et al., 2013....................  ERG 2022a.
Assumed outdoor (forecasted) conditions
 applied to indoor workers (n=2):
    Cai et al., 2018........................  OSHA.
    Adhvaryu et al., 2020...................  ERG 2022c.
Temperature conditions did not vary (n=5):
    Schlader et al., 2011...................  OSHA.
    Uchiyama et al., 2022...................  OSHA.
    Schranner et al., 2017..................  ERG 2022a.
    Constable et al., 1994..................  ERG 2022a.
    Morrissey-Bassler et al., 2024..........  OSHA.
Temperature range was entirely below the
 initial heat trigger (n=3).
    Van Cutsem et al., 2015 (HI of 77[deg]F   OSHA.
     for HOT condition).
    Federspiel et al., 2004 (HI of            ERG 2022c.
     78.8[deg]F for HOT condition).
    Niemel[auml] et al., 2002 (HI of          ERG 2022a.
     77.2[deg]F for HOT condition).
Temperature range was entirely above the
 high heat trigger (n=3):
    Meegahapola and Prabodanie, 2018 (HI of   ERG 2022c.
     90.1[deg]F for REF condition).
    Wyndham, 1969 (HI of 97.5[deg]F for REF   OSHA.
     condition).
    Ismail, 2009 (HI of 92[deg]F for REF      ERG 2022c.
     condition).
Unable to reproduce temperature data (n=2):
    Masuda et al., 2021.....................  ERG 2022c.
    Sett and Sahu, 2014.....................  ERG 2022c.
Review studies, no empirical productivity
 data (n=15):
    Ioannou et al., 2022....................  ERG 2022a.
    Borg et al., 2021.......................  ERG 2022a.
    Dasgupta et al., 2021...................  ERG 2022a.
    Morrissey et al., 2021a.................  ERG 2022a.
    Morrissey et al., 2021b.................  ERG 2022a.
    Foster et al., 2020.....................  OSHA.
    Morris et al., 2020a....................  ERG 2022a.
    Morris et al., 2020b....................  ERG 2022b.
    Day et al., 2019........................  ERG 2022a.
    Flouris et al., 2018....................  ERG 2022a.
    Lundgren et al., 2013...................  ERG 2022c.
    Sepp[auml]nen et al., 2006..............  ERG 2022c.
    Pilcher et al., 2002....................  ERG 2022c.
    Hancock et al., 2007....................  OSHA.
    Lai et al., 2023........................  OSHA.
Modelling studies, no empirical productivity
 data (n=19):
    Casey et al., 2021......................  OSHA.
    Szewczyk et al., 2021...................  ERG 2022a.
    Atlantic Council/Vivid Economics 2021a..  OSHA.
    Atlantic Council/Vivid Economics 2021b..  OSHA.
    Atlantic Council/Vivid Economics 2017...  OSHA.
    Br[ouml]de et al., 2018.................  ERG 2022c.
    Takakura et al., 2017...................  ERG 2022a.

[[Page 71015]]

 
    Carleton and Hsiang, 2016...............  ERG 2022a.
    Costa et al., 2016......................  OSHA.
    Yi and Chan, 2015.......................  ERG 2022b.
    House et al., 2003......................  ERG 2022b.
    Kjellstrom et al., 2009a................  ERG 2022a.
    Koehn and Brown, 1985...................  ERG 2022c.
    Srinavin and Mohamed, 2003..............  ERG 2022c.
    International Labour Organization, 2019.  OSHA.
    Kjellstrom et al., 2016a................  OSHA.
    Kjellstrom et al., 2009b................  OSHA.
    Kjellstrom et al., 2017.................  OSHA.
    Kjellstrom et al., 2016b................  OSHA.
Outcome was heat strain (n=5):
    Wyndham, 1965...........................  OSHA.
    Kalkowsky and Kampmann, 2006............  OSHA.
    Miller et al., 2011.....................  OSHA.
    Ioannou et al., 2021a...................  ERG 2022a.
    Kaltsatou et al., 2020..................  ERG 2022b.
Outcome was physical activity or maximum
 work capacity (n=2):
    Mix et al., 2019........................  OSHA.
    Maresh et al., 2014.....................  OSHA.
Outcome was cognitive performance (n=3):
    Fine and Kobrick, 1987..................  ERG 2022c.
    Mazlomi et al., 2017....................  ERG 2022c.
    Spector et al., 2018....................  ERG 2022c.
Outcome was heat-related injuries (n=1):
    Park et al., 2021.......................  ERG 2022a.
Outcome was loss of labor supply (including
 missed work hours) (n=2):
    Neidell et al., 2021 (ATUS).............  ERG 2022a.
    Graff-Zivin and Neidell, 2014 (ATUS)....  ERG 2022a.
Outcome was non-working time (n=5):
    Flouris et al., 2020 (unplanned break     ERG 2022a.
     time).
    Ioannou et al., 2021b (unplanned break    ERG 2022c.
     time).
    Yi and Chan, 2017 (non-productive time).  ERG 2022c.
    Li et al., 2016 (idle time).............  ERG 2022c.
    Zhao et al., 2009 (heat tolerance time).  OSHA.
Outcome was payroll or income data (n=3):
    Deryugina and Hsiang, 2014..............  ERG 2022c.
    Park, 2016..............................  ERG 2022c.
    Heal and Park, 2013.....................  OSHA.
Outcome was crop yields (n=1):
    Houser et al., 2014.....................  OSHA.
Outcome was firm-level output (no worker-
 level data available) (n=1):
    Cachon et al., 2012.....................  ERG 2022c.
Productivity losses were self-reported
 (e.g., surveys, focus groups) (n=9):
    Krishnamurthy et al., 2017..............  ERG 2022c.
    Zander et al., 2015.....................  ERG 2022c.
    Langkulsen et al., 2010.................  ERG 2022c.
    Fahed et al., 2018......................  ERG 2022c.
    Budhathoki and Zander, 2019.............  ERG 2022c.
    Singh et al., 2015......................  ERG 2022c.
    Poga[ccaron]ar et al., 2019.............  ERG 2022c.
    Morera et al., 2020.....................  ERG 2022a.
    Wadsworth et al., 2019..................  ERG 2022a.
Provided single productivity estimate for a
 range of temperatures (n=6):
    Sadiq et al., 2019......................  ERG 2022c.
    Hansson et al., 2024....................  OSHA.
    Glaser et al., 2022.....................  ERG 2022b.
    Prince et al., 2020.....................  ERG 2022b.
    Wegman et al., 2018.....................  ERG 2022b.
    Bodin et al., 2016......................  ERG 2022b.
Provided single productivity estimate for
 multiple worksites with different
 conditions (n=2):
    Stevens, 2017...........................  OSHA.
    Gun and Budd, 1995......................  ERG 2022c.
Productivity data not comparable; workers
 observed or total work time varied (n=3):
    Sawka et al., 2015......................  OSHA.
    Nag et al., 2006........................  OSHA.
    Morrison, 1969..........................  OSHA.
Productivity data for firefighting tasks
 only (n=2):
    Larsen et al., 2015.....................  ERG 2022c.
    Sol et al., 2021........................  ERG 2022c.

[[Page 71016]]

 
Provided breaks but did not specify type
 (scheduled vs. if-needed) or duration/
 frequency (n=4):
    Mitchell et al., 2018...................  ERG 2022c.
    Quiller et al., 2017....................  ERG 2022c.
    Ciuha et al., 2019......................  ERG 2022c.
    Pan et al., 2021........................  ERG 2022a.
Used work-time shifting instead of breaks
 (n=1):
    Morabito et al., 2020...................  OSHA.
------------------------------------------------------------------------

I. Appendix B. Review of Literature on Effects of Heat Exposure on Non-
Health Outcomes

I. Introduction
    A large literature from multiple disciplines (economics, 
occupational health, physiology) documents the negative effects of heat 
exposure on human health, such as mortality, injuries, and illnesses 
(for detailed discussion, see Section IV., Health Effects and Section 
V.A., Risk Assessment).
    There is also a large literature that documents the negative 
effects of heat exposure on a broad range of non-health outcomes with 
potential economic implications (Heal and Park, 2016; Lai et al., 
2023).
    This document serves several purposes. First, this document 
synthesizes and summarizes the findings from multiple disciplines 
regarding the effects of heat exposure on non-health outcomes with 
potential economic implications. In particular, this document aims to 
examine a broad set of non-health outcomes that are potentially 
relevant to OSHA's economic analysis for the proposed standard for Heat 
Injury and Illness Prevention in Outdoor and Indoor Work Settings. 
Although the discussion centers around labor productivity, other 
outcomes are also discussed, including but not limited to labor supply, 
mental performance, economic output, and worker utility. This document 
also aims to clarify terminology, given that different terms have been 
used interchangeably in the existing literature (Dasgupta et al., 2021, 
p. e457).\117\
---------------------------------------------------------------------------

    \117\ For example, Burke et al. (2023) conducted a meta-analysis 
of 22 studies as part of their literature review of existing 
evidence of ``labor productivity response to temperature.'' Some of 
these studies reported effects on mental performance or effects on 
economic output without clearly delineating the contribution of 
labor productivity. Changes in mental performance (e.g., error 
rates) may not directly reflect the magnitude of changes in labor 
productivity; for example, a 50% decrease in the error rate does not 
necessarily mean a 50% increase in labor productivity (Fisk, 2000, 
pp. 555-556). Flouris et al. (2018) conducted a meta-analysis of 111 
studies on the effects of heat exposure on workers' outcomes, 11 of 
which were related to ``productivity loss.'' Some of these studies 
reported effects on self-perceived labor productivity or labor 
supply.
---------------------------------------------------------------------------

    Studies summarized in this document were identified as follows. 
Eastern Research Group (ERG) performed several literature searches 
(ERG, 2022a; ERG, 2022b; ERG, 2022c) that could inform the relationship 
between heat and various outcomes (e.g., labor productivity, heat 
strain). Among these studies, studies reporting non-health outcomes 
were considered relevant. Studies reporting health outcomes like heat 
strain and work-related HRIs were not considered relevant, and readers 
are referred to relevant sections of the preamble for more detail. OSHA 
also independently identified additional studies pertaining to non-
health outcomes. During this process, studies about general population-
related outcomes (e.g., heat-related mortality for general population 
beyond workers) were considered irrelevant.
    This document is organized as follows. Section VIII.I.II. 
summarizes the literature's findings on the negative effects of heat 
exposure on non-health outcomes with potential economic implications, 
especially labor productivity. Section VIII.I.III. summarizes the 
literature's findings on the role of workplace characteristics in the 
labor productivity effects of heat exposure. Section VIII.I.IV. 
concludes.
II. Effect of Heat Exposure on Non-Health Outcomes
    This section summarizes the literature's findings on the negative 
effects of heat exposure on non-health outcomes that could translate 
into economic costs: labor supply, labor productivity, mental 
performance, economic output, and worker utility.\118\
---------------------------------------------------------------------------

    \118\ In general, the findings in this appendix (and other PEA 
sections that discuss benefits that are excluded from the primary 
benefits quantification) may be interrelated, such that simply 
summing the effects identified could lead to some amount of double-
counting or other mis-counting.
---------------------------------------------------------------------------

A. Labor Supply
    Literature has documented the negative effects of heat exposure on 
labor supply (hours worked), by increasing absenteeism due to illness 
or injury (Ioannou et al., 2022, p. 80) or increasing disutility of 
labor (working in the heat causes discomfort so workers increasingly 
avoid spending time at work at higher temperatures) (Lai et al., 2023, 
p. 222).
    Many studies found that heat exposure increased absenteeism due to 
illness or injury in their evaluation of multiple types of health 
information datasets, such as workers' compensations claims data, 
emergency department visits and hospital discharge datasets (for more 
detail, see Section IV., Health Effects and Section V.A., Risk 
Assessment).
    Many studies in the economics literature found evidence that heat 
exposure led workers to allocate less hours to work (potentially due to 
absenteeism from illness or injury, increased disutility of work, or 
both). Graff Zivin and Neidell (2014) used data from the American Time 
Use Survey (ATUS) to find that workers in ``high-risk industries'' 
(agriculture, forestry, fishing, hunting, mining, construction, 
manufacturing, transportation, utilities) reduced their time allocated 
to labor by one hour when daily maximum ambient temperatures exceeded 
85 [deg]F (29.4 [deg]C) compared to the 76 [deg]F-80 [deg]F (24.4 
[deg]C-26.7[deg]C) range. Almost all the decrease in the time allocated 
to labor happened at the end of the day when fatigue from prolonged 
exposure to heat has likely set in. They also found that that most of 
the decreased time allocated to labor was diverted to indoor leisure. 
They did not find evidence that workers worked longer during cooler 
days to make up for reduced work hours during hot days. Rode et al. 
(2022) compiled time use and labor force survey data from seven 
countries (Brazil, France, India, Mexico, Spain, UK, USA) and found 
that a day at daily maximum ambient temperature 104 [deg]F (40 [deg]C) 
lead to 28.65 fewer minutes worked per worker compared to a day at 80.6 
[deg]F (27 [deg]C) for ``high-risk

[[Page 71017]]

industries'' (agriculture, mining, construction, manufacturing); the 
corresponding decline was insignificant for workers in ``low-risk 
industries'' (p. 21). Garg et al. (2020a) found in Chinese time use 
survey data that an additional day with an average ambient temperature 
above 80 [deg]F (26.7 [deg]C) reduced weekly work time by 1.2 hours. 
They also found limited evidence for this reduced work time being 
substituted by increased non-work time such as time spent on childcare 
and household chores.\119\
---------------------------------------------------------------------------

    \119\ The authors found that higher temperatures reduce time 
spent on childcare by households without cooling technology 
(insignificant effect on households with cooling technology). They 
also found that higher temperatures reduce time spent on childcare 
by women (insignificant effect for men).
---------------------------------------------------------------------------

    The effect of heat exposure on labor supply likely depends on the 
incentive structures \120\ for these workers and their economic 
dependence on the income arising from their work (Lai et al., 2023). 
Using daily attendance records from selected manufacturing firms in 
India, Somanathan et al. (2021) found that elevated temperatures in the 
current or preceding week reduced labor supply \121\ (which the authors 
interpreted as possibly both increased absenteeism from illness or 
injury and increased disutility of labor), and the effect was stronger 
for workers with paid leave. Such dependence on specific incentive 
structures might explain the differences in results across studies. For 
example, Cai et al. (2018) examined worker attendance data from 
administrative records and found that neither the attendance decision 
nor the working hours of workers in a manufacturing facility in China 
were affected by temperature, likely because the workers were paid by 
piece-rate. Neidell et al. (2021) found in ATUS data that the 
relationship between hours worked and temperature depended on overall 
economic conditions. They found that during economic expansions, each 
additional degree above daily maximum ambient temperature 90 [deg]F 
(32.2 [deg]C) reduced the average workday by 2.6 minutes. On the other 
hand, no significant relationship was found between temperature and 
hours worked during economic recessions. Such lack of evidence of 
reduction in work hours on hotter days during weak labor market 
conditions suggests that the negative relationship between temperature 
and work hours is likely driven by changes in labor supply (from 
worker) rather than labor demand (from employer).
---------------------------------------------------------------------------

    \120\ The role of workplace incentives in the labor productivity 
effects of heat exposure is discussed later in section VIII.I.III.B.
    \121\ This study's worker attendance data technically measures 
only whether the worker is present or absent that day (Somanathan et 
al., 2021, p. 1811). It is unclear if and how their attendance data 
captures cases where the worker is only partially present, and 
leaves work early that day.
---------------------------------------------------------------------------

    There are several reasons for the need for caution in interpreting 
the studies reporting effects of heat exposure on labor supply (or 
employment in general).
    First, the results presented in most of these studies could be 
driven by changes in labor demand as well as labor supply (Graff Zivin 
and Neidell, 2014, p. 4). Some studies did try to differentiate labor 
supply and demand, such as estimating the effect across business cycles 
(Neidell et al., 2021) or estimating wage effects as well as employment 
effects (e.g., Colmer, 2021; Jessoe et al., 2018).
    Second, most economics studies reporting the negative effect of 
heat exposure on labor supply using data on hours worked did not 
disentangle the contribution of absenteeism due to illness or injury 
from the contribution of disutility from working in the heat. The 
distinction is important because improving workplace conditions may 
increase labor supply beyond reducing time lost to illness or injury.
    Third, it is not very clear if reduced work time always has 
negative implications for worker welfare. Reduced work time on hot days 
such as cessation of work might be beneficial for workers if fewer 
workers are exposed to high temperatures that put their health at risk 
(Ireland et al., 2024, p. 18). However, if the lost work time is not 
compensated, workers face a tradeoff between health risk and earnings 
risk, both of which negatively affects the workers' welfare (EPA, 2021, 
p. F-3). Rode et al. (2022)'s theoretical framework also presented a 
similar tradeoff facing workers between decreased earnings and 
increased disutility of labor in face of higher temperatures. Their 
theoretical framework is based on their interpretation of their 
empirically-estimated decline in labor supply due to higher 
temperatures (discussed above) as uncompensated lost work time--workers 
choose to work less due to increased disutility of labor but at the 
cost of foregoing earnings. Based on this theoretical framework, they 
derived the willingness-to-pay to avoid the increased disutility of 
labor from higher temperatures (defined as the increase in the wage 
rate that is needed to offset the increased disutility of labor).
    Fourth, the definition of work hours varies by dataset. Some 
datasets include, for example, paid or unpaid leave (Somanathan et al., 
2021) or while other datasets include time spent on job search \122\ 
(studies that use the ATUS such as Graff Zivin and Neidell, 2014; 
Neidell et al., 2021; Rode et al., 2022). How work hours are defined 
has implications for the worker welfare effects of heat exposure. For 
example, as discussed above, worker welfare could depend on whether the 
reduced work hours from heat exposure are compensated (e.g., worker 
leaves work early forgoing pay versus using paid leave). See Eldridge 
et al. (2022) for more examples of various definitions of work hours 
across datasets.
---------------------------------------------------------------------------

    \122\ Using the ATUS and following the ``same methodology 
employed by'' Graff Zivin and Neidell (2014). Neidell et al. (2021) 
defined ``work'' as ``all activities under the `work and work-
related activities' major category,'' which ``in addition to time 
spent at the workplace, [. . .] also includes time devoted to other 
income-generating activities as well as job searching'' (p. 2). Rode 
et al. (2022) also uses the same category to calculate time spent on 
work: ``Total work is calculated as the sum of all time spent 
engaged in sub-activities listed under Category 5, Work and Work-
Related Activities. Relevant sub-categories include time spent in 
work itself, income-generating activities, socializing as a part of 
work, job searching, and other miscellaneous work-related 
activities'' (p. 52).
---------------------------------------------------------------------------

B. Labor Productivity
    Numerous studies have documented the negative effects of heat 
exposure on labor productivity. Using direct measures of labor 
productivity (units of output produced per hour) and proxies of labor 
productivity (physical work capacity, physical activity, and self-
perceived labor productivity), studies across various disciplines 
(e.g., physiology, occupational health, and economics) have found that 
heat exposure reduces labor productivity (Ioannou et al., 2022; 
Morrissey et al., 2021a; Mattke et al., 2007).
    This section focuses on micro-level evidence across various 
disciplines based on laboratory or occupational settings. Studies 
reporting potential macro-level evidence on labor productivity based on 
macroeconomic proxies of labor productivity (e.g., per capita value 
added, revenue, payroll) are discussed in section VIII.I.II.D.
    Overall, studies reported varying estimates of effects of heat 
exposure on labor productivity depending on the specific sectors and 
heat conditions (e.g., presence of indoor radiant heat, differences in 
regional climate between the U.S. and non-U.S. countries). Section 
VIII.I.III. discuses in more detail workplace factors that affect the 
literature's estimates of the effect of heat exposure on labor 
productivity, such as contractual structures and adaptation measures 
that affect workers' incentives and ability to be productive in the 
heat.

[[Page 71018]]

I. Direct Measures of Labor Productivity
    Labor productivity is a ``measure of economic performance that 
compares the amount of goods and services produced (output) with the 
amount of labor hours worked to produce that output'' and is a ``ratio 
of output to hours worked'' (BLS, 2020a). Changes in labor productivity 
``reflect the changes in output that is not explained by the change in 
hours worked'' (BLS, 2020a). Studies have documented the effects of 
heat exposure on labor productivity in different work settings in both 
U.S. and non-U.S. countries. Most of these studies are occupational 
studies with the exception of one laboratory-based study involving 
simulated work.
    Some studies discussed in this section technically reported changes 
in an average worker's output per day or week, not output per hour. 
These studies are discussed in this section in the context of labor 
productivity based on their evidence that changes in their reported 
outcomes are likely being driven by changes in worker output per hour, 
not by changes in daily or weekly hours worked.
a. Agriculture.
    Many studies analyzing the labor productivity effects of heat 
exposure are based on agricultural work settings, given the 
agricultural sector's high level of heat exposure and the feasibility 
of tracking individual production levels.
    Using daily production data of Indian rice harvesters, Sahu et al. 
(2013) reported a 5% decline in labor productivity (rice bundles per 
worker per hour) for each additional degree above 26 [deg]C WBGT. Using 
daily production data of sugarcane cutters in Nicaragua, Hansson et al. 
(2024) reported that relative to below 82.4 [deg]F (28 [deg]C) WBGT, 
labor productivity (bundles per worker per day) decreased by 2.5% at 
82.4 [deg]F-84.2 [deg]F (28 [deg]C-29 [deg]C) WBGT, by 5% at 86 [deg]F-
87.8 [deg]F (30 [deg]C-31 [deg]C) WBGT, and by 8.3% at above 87.8 
[deg]F (31 [deg]C) WBGT. Using daily production data of maize farmers 
in Nigeria, Sadiq et al. (2019) reported that for every 1.8 [deg]F (1 
[deg]C) increase in WBGT, labor productivity (ridges tilled or hoed per 
worker per hectare) decreased by 23% although their reported labor 
productivity effects of higher temperature could be confounded by the 
effects of fatigue over the workday. Using daily production data of 
sheep shearers and retrospective temperature records of a ``Bureau of 
Meteorology recording station'' in Australia, Gun and Budd (1995) 
reported that the labor productivity (number of sheep shorn per worker 
per hour) declined by approximately 7% per 1.8 [deg]F (1 [deg]C) 
increase in ambient temperature \123\ although the estimated effect was 
not statistically significant. Using daily production data of 
Guatemalan sugarcane workers, Dally et al. (2018) reported that a day 
with 95th percentile WBGT of 34 [deg]C was associated with an estimated 
cumulative loss in labor productivity of 0.59 tons of cut sugarcane per 
worker per day over the following five days compared to a day with 95th 
percentile WBGT of 29 [deg]C (approximately 0.59/5.7=10.35% of the 
average production per worker per day).
---------------------------------------------------------------------------

    \123\ This corresponds to a linear approximation of the results 
presented in Figure 5 of the study.
---------------------------------------------------------------------------

    Based on data from tree fruit harvesters in Washington State, 
Quiller et al. (2017) found that increasing daily maximum WBGT was 
associated with decreasing labor productivity (weight of fruit bins 
collected per worker per hour). However, this association became 
statistically insignificant after controlling for potential confounders 
such as price paid per bin and shift duration. The lack of evidence 
could also be due to relatively cool climate of Washington State--the 
time-weighted average WBGT was 72.1 [deg]F (22.3 [deg]C) and 60.6 
[deg]F (15.9 [deg]C) in each of the months studied.
b. Manufacturing
    Several studies that directly measure labor productivity are based 
on manufacturing settings, likely due to feasibility of tracking 
individual production levels.
    Using daily production data from a non-climate-controlled paper cup 
manufacturing setting in China, Cai et al. (2018) reported that daily 
maximum ambient temperatures above 95 [deg]F (35 [deg]C) resulted in an 
approximately 8.5% decrease in labor productivity (output per worker 
per day) relative to the baseline range of 75 [deg]F-79 [deg]F (23.9 
[deg]C-26.1 [deg]C). Using daily production data from a rubber compound 
manufacturing plant in Sri Lanka, Meegahapola and Prabodanie (2018) 
reported that high temperature ranges, 105.8 [deg]F-113 [deg]F (41 
[deg]C-45 [deg]C) and 96.8 [deg]F-104 [deg]F (36 [deg]C-40 [deg]C), 
reduced labor productivity (kilogram per worker per hour), by 22% and 
18% respectively, relative to the baseline temperature range of 89.6 
[deg]F-95 [deg]F (32 [deg]C-35 [deg]C). Using weekly production data of 
brick molders and carriers in India, Sett and Sahu (2014) found that 
for each 1.8 [deg]F (1 [deg]C) increase in ambient temperature, labor 
productivity (number of bricks molded or carried per worker per week) 
declined by 0.8%. Using daily worker-level production data from 
selected manufacturing firms in India, Somanathan et al. (2021) found 
that labor productivity (output per worker per day) declines in higher 
outdoor temperatures, falling 2.7% per 1.8 [deg]F (1 [deg]C) increase 
in daily maximum ambient temperature above 77 [deg]F (25 [deg]C).
c. Other Sectors
    Direct units of output are harder to measure in most other sectors, 
so comparatively fewer studies have been produced in other industries.
    Observing call center workers in California, Federspiel et al. 
(2004) found that time to finish tasks (post-talk wrap-up to process 
information) increased by 16% when the ambient temperature increased 
from 73.4 [deg]F to 77.7 [deg]F (23 [deg]C to 25.4 [deg]C). 
Niemel[auml] et al. (2002) also analyzed workers at two call centers. 
In one call center, they compared labor productivity (number of calls 
per hour) between two different temperature zones in the building. In 
another cell center, they introduced an intervention (installation of 
air-conditioning) and compared labor productivity before and after the 
intervention. They reported that labor productivity in both call 
centers decreased by 5% to 7% at ambient temperatures over 77 [deg]F 
(25 [deg]C), although other seasonal changes likely confounded their 
results. From data on Demographic and Health Surveys (DHS) interviewers 
from 46 developing countries, LoPalo (2023) estimated the effects of 
heat exposure on DHS interviewers' labor productivity (number of 
surveys completed per hour). Exploiting variation in weather within a 
region of a country, survey waves, and interviewers, they found 
interviews per hour were fewer by 13.6% on days over 85 [deg]F (29.4 
[deg]C) wet bulb relative to days between 50 [deg]F (10 [deg]C) and 60 
[deg]F (15.6 [deg]C) wet bulb. Hanna (2004) conducted an experiment in 
an environmental test chamber with journeymen electricians installing 
duplex receptacles on work panels. While their laboratory setting did 
not allow effects of real-world workplace factors that affect labor 
productivity, the controlled environment tracked heat exposure in 
detail by ambient temperature and humidity level. The study found that 
maximum labor productivity (number of receptables installed per hour) 
was achieved at ambient temperature between 40 [deg]F (4.4 [deg]C) and 
70 [deg]F (21.1 [deg]C) with relative humidity below 80%. At 70% 
relative humidity, labor productivity decreased by 10% when ambient 
temperature increased from 70 [deg]F (21.1 [deg]C) to 90 [deg]F (32.2 
[deg]C) (and by 23% when ambient temperature increased to 100 [deg]F 
(37.8 [deg]C)). They also found that higher

[[Page 71019]]

relative humidity reduced labor productivity further at elevated 
ambient temperatures.
II. Proxies for Labor Productivity
    This section summarizes findings of studies that report 
``alternative'' measures of labor productivity, such as physical work 
capacity, physical activity, and self-perceived labor productivity.
a. Physical Work Capacity, Exposure-Response Functions
    Work capacity or physical work capacity is the potential to perform 
work under specified set of environmental conditions (e.g., WBGT) and 
physical condition of the worker (e.g., core body temperature, heart 
rate) (Ioannou et al., 2022, p. 75; Br[ouml]de et al., 2018, p. 332). 
Loss of work capacity occurs as a physiological response to heat 
exposure where the worker reduces physical activity to avoid negative 
health effects (e.g., increases in core body temperature or heart rate 
beyond the safe limit) (Kjellstrom et al., 2014).
    Several studies have derived exposure-response functions that 
represent the relationship between heat exposure and work capacity. 
Exposure-response functions in the occupational health literature fall 
into two groups (Borg et al., 2021). The first group of exposure-
response functions are based on empirical data (e.g., Kjellstrom et 
al., 2014; Foster et al., 2021). The second group are based on 
recommended work-rest ratios in existing work-rest guidelines by NIOSH, 
ACGIH, and ISO (e.g., Kjellstrom et al., 2009b; Dunne et al., 2013).
b. Empirically-Derived Exposure-Response Functions
    As part of the High Occupational Temperature Health and 
Productivity Suppression (Hothaps) Programme, Kjellstrom et al. (2014) 
derived an exposure-response function (henceforth ``Hothaps function'') 
linking WBGT to work capacity for three levels of work intensity (200 
W, 300 W, 400 W) based on the empirical data involving acclimatized 
male workers in Wyndham (1969) (miners in South Africa) and Sahu et al. 
(2013) (rice harvesters in India).
    Foster et al. (2021) derived an exposure-response function 
(henceforth ``PWC function'') linking varying environmental conditions 
to work capacity based on empirical data collected from one-hour trials 
involving young, unacclimatized males performing physical work in 
climatic chambers. In this study, work capacity is defined as the 
``maximum physical work output that can be reasonably expected from an 
individual performing moderate to heavy work over an entire shift.'' 
More specifically, Foster et al. (2021) aimed to measure the amount of 
work that can be performed across varying environmental conditions 
(e.g., combinations of air temperature and relative humidity) while 
maintaining a fixed heart rate at a maximally acceptable level (e.g., 
130 beats per minute) as a ``surrogate for self-paced physical 
workloads.'' Smallcombe et al. (2022) replicated the environmental 
conditions of Foster et al. (2021) and computed work capacity during 6 
work-rest cycles of 50-minute work/10-minute rest, with a 1-hour break 
after the first 3 cycles.
    There are some benefits of evaluating the work capacity effects of 
heat exposure. Heat exposure-work capacity response functions 
(exposure-response) could be applied to macroeconomic data and models 
to estimate the economic impact of heat exposure (more examples of 
studies that borrow these exposure-response functions are discussed 
more detail below in section VIII.I.II.D.II.). Like Foster et al. 
(2021) and Smallcombe et al. (2022), work capacity could also be 
measured through laboratory experiments in controlled environments, 
reducing the influence of confounders and making their results 
generalizable across various environmental conditions.
    However, there are caveats with interpreting the effects of heat 
exposure on work capacity reported in the studies above.
    First, they may underestimate the labor productivity effects 
observed in actual work settings for several reasons (Ioannou et al., 
2022). Heat exposure could reduce labor productivity not only through 
reduced work capacity but also other factors such as increased central 
fatigue and reduced cognitive performance. Also, as discussed more 
below in section VIII.I.III.B., workplace factors such as wage 
structure may not always incentivize workers to sustain high levels of 
effort at the maximum capacity every day throughout the entire shift.
    Second, these studies may also overestimate the labor productivity 
effects observed in actual work settings where self-pacing is more 
limited. Although self-pacing is observed in most workplaces, there are 
some workplaces where ability to self-pace is limited, such as 
emergency response activities or work performed on commission (Ioannou 
et al., 2022).
    Third, some studies assume what is the physically maximally 
acceptable level (e.g., 130 beats per minute) which may not be 
appropriate for every worker. From the perspective of applying their 
findings to actual work settings, ``it is not clear how various 
physiological (dehydration, cardiac fatigue, poor sleep quantity/
quality) and psychological (motivation, anxiety) states impact upon 
what a worker deems as an acceptable working heart rate'' (Ioannou et 
al., 2022).
c. Guideline-Based Exposure-Response Functions
    The second group of exposure-response functions are based on 
recommended work-rest ratios in existing work-rest guidelines set by 
NIOSH, ACGIH, and ISO (e.g., Kjellstrom et al., 2009b; Dunne et al., 
2013).
    There are several reasons for the need for caution when 
interpreting the guideline-based exposure-response functions.
    First, work-rest guidelines represent the ``the proportions of work 
hours during which workers need to take rest periods, depending on work 
intensity and WBGT, in order to avoid the core body temperature 
exceeding 38 [deg]C for an average worker'' (Kjellstrom et al., 2009a). 
Exposure-response functions based on work-rest guidelines are ``highly 
conservative because their objective is to minimize the risk of core 
body temperature of the average worker exceeding 38 [deg]C'' (Foster et 
al., 2021). Guideline-based exposure-response functions therefore show 
greater declines in work capacity in higher temperatures than the 
empirically-derived functions (Kjellstrom et al., 2014, p. 17; 
Morrissey et al., 2021a, Figure 3).
    Second, work-rest guidelines prescribe how much a worker should 
reduce their work capacity at different levels of heat exposure. They 
do not represent the causal effect of heat exposure on work capacity 
(Foster et al., 2021, p. 1216).
d. Physical Activity
    Some studies tracked the participants' level of physical activity, 
based on methods such as direct observation of work activities (that 
are then categorized into direct work, indirect work, and idle time), 
time-motion analysis (video recording movements that are then paired 
with metabolic equivalents) and accelerometers tracking data (step 
counts per minute which are also paired with metabolic equivalents). 
Although these methods do not directly track any effects on output, 
they measure changes in levels of labor input. A major advantage of 
these methods is that study participants are monitored in their

[[Page 71020]]

actual working conditions, reflecting behavioral thermo-regulation 
(e.g., self-pacing and varying clothing insulation) and endogenous 
changes in effort in response to workplace incentives like piece-rate 
pay (Ioannou et al., 2022).
    Li et al. (2016) and Yi and Chan (2017) directly observed rebar 
construction workers whose activities are categorized into direct work 
(activities that directly and productively contribute to task 
completion, i.e., steel bar reinforcement), indirect work (support 
activities that do not directly or productively contribute to task 
completion, such as walking with tools/materials or empty-handed, 
waiting for materials to be lifted, discussing tasks with foreman/
coworkers), or idle time (personal time and non-utilization time due to 
work stoppage from any cause). Observing the activities of rebar 
construction workers in Hong Kong, Yi and Chan (2017) found that a 1.8 
[deg]F (1 [deg]C) increase in hourly average WBGT was associated with 
an approximately 2.8 percentage-point (%p) decrease in the share of 
direct work time (corresponding to 2.8/64 = 4.38% of the average share 
of direct work time; \124\ effects on the rest of the categories were 
not reported). Observing the activities of rebar construction workers 
in China, Li et al. (2016) reported that a 1.8 [deg]F (1 [deg]C) 
increase in hourly average WBGT was associated with a 0.57 %p decrease 
in the share of direct work time (corresponding to 0.57/74 = 0.77% of 
the average share of direct work time) and a 0.74 %p increase in the 
share of idle time (corresponding to 0.74/11 = 6.72% of the average 
share of idle time) (0.18 %p decrease was also observed in the share of 
indirect work time, but the effects were not significant). Unlike Yi 
and Chan (2017) that controlled for when the temperature was measured 
during the workday, a caveat with Li et al. (2016) is that their 
reported effects of higher temperatures could be confounded by effects 
of fatigue over the workday.
---------------------------------------------------------------------------

    \124\ The study's abstract reported the share of direct work 
time ``decreasing by 0.33%'' per 1.8 [deg]F (1 [deg]C) WBGT 
increase--OSHA conjectures that this statement meant that the 
estimated 2.8 %p decrease is 3.3% of the predicted average share of 
direct work time at 22.28 [deg]C WBGT (lowest observed WBGT in their 
data) according to their regression model where the covariates are 
held at their sample average values (some of which are not reported 
in the study).
---------------------------------------------------------------------------

    Using time-motion analysis on a sample of construction workers in 
Spain over two days, Flouris et al. (2020) found that the workers take 
longer irregular breaks during the hotter day, Day 1 with a WBGT range 
71.2 [deg]F-99.1 [deg]F (21.8 [deg]C-37.3 [deg]C). They found a 4.7-
fold difference between the time lost due to irregular work breaks on a 
hot day (Day 1) compared to a cool day (Day 2), with a WBGT range 71.4 
[deg]F-88.9 [deg]F (21.9 [deg]C-31.6 [deg]C). Moreover, they also found 
that a planned break intervention providing hydration to workers could 
partially offset these irregular breaks.
    Mitchell et al. (2018) used accelerometer data to track the 
physical activity of Californian farmworkers for one work shift each in 
the summers of 2014 and 2015. They found that an 18 [deg]F (10 [deg]C) 
increase in median WBGT reduced physical activity by 135 counts per 
minute compared to an average of 347 counts per minute across all 
participants (equivalent to a 3.9% decrease per 1.8 [deg]F (1 [deg]C) 
WBGT).
    There are some caveats with using physical activity as a measure of 
labor productivity.
    First, physical activity measures the amount of labor inputs 
instead of actual output. Some studies such as Ioannou et al. (2022) 
considered the focus on labor inputs rather than production output as 
an advantage; for instance, expressing labor productivity as the amount 
of crop produced implies constant availability and equal distribution 
of crops across the tested piece of land. However, changes such as 
unequal crop availability are not problematic unless they are 
systematically correlated with changes in heat exposure.
    Second, for studies based on accelerometer data, without 
information if other production inputs exist and how they affect output 
(e.g., capital), the relationship between physical activity (counts per 
minute) and labor productivity is uncertain. For example, suppose there 
are two workplaces exposed to the same temperature and workers display 
the same level of physical activity but one workplace has machines that 
assist the workers. Given the same level of temperature and physical 
activity, the workplace that has machines available could achieve 
higher labor productivity.
e. Self-Perceived Labor Productivity
    Based on worker surveys, some studies document effects of heat on 
self-perceived labor productivity, partly due to the comparative ease 
of obtaining such measurements. Compared to actual production data, the 
self-perceived measures are a less accurate measure of output and can 
be affected by other factors that impact an individual's self-perceived 
labor productivity, such as individual's level of awareness of heat 
stress.
    Krishnamurthy et al. (2017) administered a standardized high 
occupational temperature health and productivity suppression 
questionnaire to 84 steel factory workers in India. Overall, 1% 
reported taking sick leave due to heat, 10.6% reported being less 
productive due to heat, and 27% reported that it took longer to 
complete the same tasks during summer compared to cooler seasons. Of 
the 27% who reported labor productivity losses, 91% were exposed to 
direct radiational heat during steel melting. This reduction in labor 
productivity occurred due to high heat and heavy workload despite 
taking rest breaks allowed by the management after the hot job was 
performed (work-rest regimen: 75% work, 25% rest, each hour). Workers 
reported drinking high quantities of water and rested in shade, but 
these actions did not abate the effects of heat due to the high ambient 
humidity which limits sweat evaporation and evaporative cooling. This 
study did not have a direct control group to compare the actual 
efficacy of these cooling mechanisms.
    Zander et al. (2015) conducted an online survey of 1,726 Australian 
workers and found that 70% of all surveyed workers reported 
productivity losses due to heat, corresponding to the majority (93%) of 
those that reported being stressed by heat at work. In comparison, 7% 
of respondents reported being absent from work at least one day in the 
previous 12 months due to heat, being absent for 4.4 days on average. 
Also focusing on understanding the impact of heat on Australian 
workers, Singh et al. (2015) interviewed key stakeholders 
(representatives for occupational safety and health, unions, industry, 
and government organizations) that reported labor productivity loss due 
to heat exposure, but the results were mostly qualitative and based on 
a small sample of 20 stakeholders.
    Poga[ccaron]ar et al. (2019) surveyed 70 workers in Greece and 216 
workers in Slovenia and found that most workers in both Greece (69%) 
and Slovenia (71%) reported that they felt heat stress during heat 
waves had a ``significant impact'' on their productivity. Additionally, 
60% of workers in Greece and 74% in Slovenia reported that heat stress 
significantly impacts their ``well-being.'' \125\ These two studies did 
not directly track the actual temperature exposure of these workers and 
instead relied on the workers' own recollection of the workplace 
temperatures (e.g., ``warm,'' ``hot,'' ``very hot'').
---------------------------------------------------------------------------

    \125\ Authors are not specific what ``well-being'' means.
---------------------------------------------------------------------------

    Langkulsen et al. (2010) analyzed a total of 21 Thai workers from 
four industrial sites and one agricultural site. Onsite measurements 
found that the

[[Page 71021]]

workers were exposed to WBGT ranging from 78.8 [deg]F to 94.3 [deg]F 
(25.6 [deg]C to 34.6 [deg]C). For 4 of the 5 sites, the study assessed 
the workers' self-perceived labor productivity, which revealed large 
differences between sectors. While workers in 2 of the 4 sites that 
assessed self-perceived labor productivity reported losses of self-
perceived labor productivity ranging from 10% to 60%, workers in the 
other two sites reported no losses when exposed to similar heat (e.g., 
agriculture). In general, the largest losses in self-perceived labor 
productivity were from sites that had access to shade and indoors, even 
sites with air-conditioning in some cases. The small sample size across 
diverse sites may limit the ability to generalize these results.
    Surveying farmers in Nepal, Budhathoki and Zander (2019) reported 
that perceived labor productivity loss was strongly associated with the 
perceived levels of heat stress. Moreover, respondents with ``access to 
actual weather information'' \126\ were more likely to perceive labor 
productivity losses from heat than those without this information, 
indicating that level of individuals' awareness potentially affects 
their self-reported assessments of labor productivity.
---------------------------------------------------------------------------

    \126\ Authors are not specific what ``access to actual weather 
information'' means.
---------------------------------------------------------------------------

III. Occupational Versus Laboratory Settings
    Studies discussed above in sections VIII.I.II.B.I. and 
VIII.I.II.B.II. were conducted either in occupational settings or 
laboratory settings. Both settings have advantages and disadvantages.
    Laboratory settings grant a high degree of internal validity 
because the experiments are more easily reproducible and represent a 
direct causal effect of heat that removes the influence of confounders 
(Ioannou et al., 2022). While laboratory-based studies provide a 
relevant benchmark for the effects of heat on productivity observed in 
actual work settings, they are limited in the generalizability of their 
findings to different settings (Somanathan et al., 2021). In 
occupational settings, labor productivity effects of heat would depend 
on the physical and behavioral aspects of employment, such as the wage 
contract, particularities of production processes, management 
techniques, and mechanization, which are not accounted for by 
laboratory studies (Somanathan et al., 2021).
C. Mental Performance (Cognitive Function, Decision-Making).
    The literature has documented the effect of heat exposure on mental 
performance in academic, athletic, and work settings.\127\ These 
studies often use the term ``performance'' with the intent to ``include 
a broader range of effects [such as test scores] than would be 
indicated by [labor] productivity'' (Heal and Park, 2013, p. 10).
---------------------------------------------------------------------------

    \127\ Reduced mental performance due to heat exposure (e.g., 
mistakes, inattention, long reaction time) is also linked to 
increased heat-related injuries--for a detailed discussion, see 
Section IV.P., Heat-Related Injuries.
---------------------------------------------------------------------------

    In a meta-analysis of 22 studies categorized into reaction time, 
attention/perceptual tasks, mathematical processing, or ''reasoning, 
learning, memory,'' Pilcher et al. (2002) reported that a WBGT of 90 
[deg]F (32.2 [deg]C) or greater was associated with a 14.9% decrease in 
performance compared to ``neutral temperature conditions'' defined as 
WBGT from 60 [deg]F to 69 [deg]F (15.6 [deg]C to 20.6 [deg]C). 
Moreover, they also report that these estimates are also affected by 
the duration of exposure to the heat conditions, the duration of 
exposure prior to the task onset, the type of task, and the task 
duration, which can explain the variability of results in the 
literature discussed below (test scores, athletic performance, 
workplace performance).
I. Test Scores
    Several studies found negative effects of heat exposure on 
cognitive test performance.\128\ Using student-exam level panel data of 
high school exit exam scores from New York City high schools (Regents 
Exams) from 1998 to 2011, Park (2022) found that a 1[deg]F (0.56 
[deg]C) higher average exam-time ambient temperature reduces 
performance by 0.9% of a standard deviation. Using panel data of 
individual-level cognitive test scores administered at respondents' 
homes for children as part of the National Longitudinal Survey of Youth 
(NLSY79), Graff Zivin et al. (2018) found that an additional 1.8[deg]F 
(1 [deg]C) of average daily ambient temperature above 69.8 [deg]F (21 
[deg]C) reduced math performance by 0.219 percentile point (no 
significant effects found for reading). Using student-exam level panel 
data of national college entrance exam scores in China, Graff Zivin et 
al. (2020) found that a 1.8 [deg]F (1 [deg]C) higher average exam-
period (2 days) ambient temperature reduced performance by 0.34%. Using 
panel data of individual-level cognitive test scores administered at 
respondents' homes for adults as well as children as part of a 
nationally representative biennial longitudinal survey in China, Zhang 
et al. (2024) found that a test day with an average ambient temperature 
above 89.6 [deg]F (32 [deg]C), relative to a day in the 71.6 [deg]F-
75.2 [deg]F (22 [deg]C-24 [deg]C) range, leads to a reduction in math 
performance by 6.6% of a standard deviation (no significant effects 
found for reading).
---------------------------------------------------------------------------

    \128\ Literature has also found evidence of heat exposure on 
longer-term outcomes such as student learning and adult earnings. 
Cho (2017) reported effects of summertime heat exposure on national 
college entrance exam scores in South Korea (administered nationwide 
in November). Park et al. (2020) reported effects of cumulative heat 
exposure from hotter days during the prior school year on PSAT exam 
scores of U.S. high school students. Garg et al. (2020b) reported 
effects of hotter days during the prior school year on academic 
achievement for Indian children in primary and secondary school. 
Isen et al. (2017) reported effects of heat exposure in utero on 
adult earnings in U.S. employer-employee matched longitudinal data 
from the Census Bureau's Longitudinal Employer-Household Dynamics 
(LEHD) program.
---------------------------------------------------------------------------

II. Athletic Performance
    Several studies found negative effects of heat exposure on athletic 
performance, despite this discussion being grouped with studies on 
mental performance, athletic performance is likely related to both 
mental and physical performance (Burke et al., 2023, p. 11).
    Using athlete-contest level panel data of 3,196 professional 
archers in China from 2010 to 2016, Qiu and Zhao (2022) found a 
negative effect of higher daily heat index on performance. Relative to 
the baseline heat index range of 64.4 [deg]F-71.6 [deg]F (18 [deg]C-22 
[deg]C),\129\ the study found that at sample average wind speed of 2.35 
meters per second, average score decreased by approximately 3% when the 
heat index was 78.8 [deg]F-93.2 [deg]F (26 [deg]C-34 [deg]C) and by 
10.4% when the heat index exceeded 93.2 [deg]F (34 [deg]C). They also 
found that the effect of higher heat index on performance was less 
negative for top performers (defined as athletes whose performance 
index, defined as their average scores in all contests in previous 
competitions, exceeds the 90th percentile).
---------------------------------------------------------------------------

    \129\ To compute heat indices below 80 [deg]F (26.7 [deg]C), Qiu 
and Zhao (2022) used the following formula: HI = 0.5*(T+61.0+[(T-
68.0)*1.2]+RH*0.094), where HI is heat index in Fahrenheit, T is 
ambient temperature in Fahrenheit, and RH is relative humidity in 
percentage (p. 1159, footnote 18).
---------------------------------------------------------------------------

    Using athlete-competition level panel data on 3.5 million 
collegiate track and field performances from 2005 to 2019, Sexton et 
al. (2022) found a nonlinear relationship between daily average ambient 
temperature and performance. Performance of sprint and strength events 
improved with increasing temperatures up to 75 [deg]F (23.9 [deg]C), 
after which decline in performance was

[[Page 71022]]

insignificant; on the other hand, performances in endurance events 
declined significantly when temperatures were above 60 [deg]F (15.6 
[deg]C), by 5 percentage points for each 5 [deg]F (2.78 [deg]C) 
increase in daily average ambient temperature relative to the baseline 
temperature range of 55 [deg]F-60 [deg]F (12.8 [deg]C-15.6 [deg]C).
    Using player-match level panel data on 177,000 tennis matches from 
2002 to 2017, Burke et al. (2023) found negative effects of heat 
exposure on the performance of professional tennis players (e.g., more 
double faults, more match retirement, shorter rallies, less total 
distance run). They reported a ``roughly 0.5% decline'' in player 
performance per 1.8 [deg]F (1 [deg]C) increase in average ambient 
temperature of the day of the match. They also found that the effects 
of heat exposure on performance were less negative for players ranked 
in the top 10. They also noted that their estimated effect of heat 
exposure on professional tennis players, which the authors considered 
as ``high-wage settings,'' is about ``half of the roughly 1.0%'' 
decline in labor productivity per 1.8 [deg]F (1 [deg]C) increase in 
ambient temperature that they estimated from their meta-analysis of 22 
studies. The authors conducted the meta-analysis as part of their 
literature review of existing evidence of labor productivity effects of 
heat exposure, which focused on ``lower-wage settings.''
III. Workplace Performance
    Focusing on studies based on actual office work or laboratory 
experiments that resemble office work, Sepp[auml]nen et al. (2006) 
conducted a meta-analysis of 24 published studies, concluding that 
performance decreased with a temperature above 73.4 [deg]F to 75.2 
[deg]F (23 [deg]C to 24 [deg]C). The tasks analyzed include text 
processing, simple calculations (addition, multiplication), length of 
telephone customer service time, and total handling time per customer 
for call center workers, making them comparable to cognitive tasks 
conducted in other studies. They estimated a non-linear relationship 
between performance and heat: performance decreased by 9% at 86 [deg]F 
(30 [deg]C) compared to an optimal level of 69.8 [deg]F to 71.6 [deg]F 
(21 [deg]C to 22 [deg]C).
    Some studies found evidence that heat exposure affects the mental 
performance of outdoor workers. Bendak et al. (2022) conducted a 
longitudinal empirical study to assess how high ambient temperatures 
affect construction workers' performance on a variety of tasks 
measuring reaction time, finding that task performance was lower in 
high ambient temperatures.
    However, their analysis compared summer and winter months; 
therefore, the results are possibly confounded by seasonality effects. 
Similarly, Mazlomi et al. (2017) reported that workplace heat 
conditions measured by WBGT were negatively correlated with foundry 
plant workers' performance in cognitive tests. In contrast, Spector et 
al. (2018) found no association between maximum work-shift WBGT and 
post-shift reaction time or postural sway for 46 tree fruit harvesters 
in Washington State.
D. Economic Output
    Studies that documented the economic output effects of heat 
exposure fall into two groups. The first group of studies directly 
estimated the effect on heat exposure using plant/firm-level and 
region-level output data. The second group of studies borrowed heat 
exposure-work capacity response functions from the occupational health 
literature (which are derived from empirical data or existing ACGIH/
NIOSH/ISO work-rest guidelines) and assumed workers are behaving 
according to these exposure-response functions.
I. Studies Directly Estimating the Effect on Heat Exposure Using 
Economic Output Data
    Numerous studies in the economics literature found evidence of 
negative output effects of heat exposure at the plant/firm-level and 
region-level.
    This section does not focus on studies about the effects of higher 
temperatures on economic output through other channels such as 
agricultural yield, productivity of capital (e.g., faster depreciation 
of infrastructure), labor reallocation, energy demand, and 
international trade.
    This section focuses on studies that used panel data to analyze 
changes (e.g., daily, weekly, quarterly, yearly) in temperature and 
outcomes of interest across space (e.g., plant/firm, region) and time. 
By controlling for time-invariant differences across space that may be 
confounded with temperature, the panel data approach helps to address 
some concerns over omitted variable bias associated with cross-
sectional studies (Auffhammer, 2018, p. 43; Massetti and Mendelsohn, 
2018, p. 327).
a. Plant/Firm-Level Output Effects
    Several studies found economic output effects of heat exposure 
using plant/firm-level panel data. Cachon et al. (2012) followed 64 
automobile manufacturing plants in the U.S. from 1994 to 2005 and found 
that a week with six or more days with a daily maximum ambient 
temperature exceeding 90 [deg]F (32.2 [deg]C) reduced weekly production 
by 8%. The findings control for potential confounders such as changes 
in national demand and seasonality in demand for specific types of 
automobiles. However, the data did not allow the study to distinguish 
the contribution of labor productivity and labor supply. Information on 
the extent of indoor climate controls in these manufacturing plants was 
also not available.
    Somanathan et al. (2021) estimated the output effects of heat 
exposure at different levels of aggregation (worker, plant, district) 
and found that their estimated effects are all of similar magnitude. 
Using daily worker-level production data from selected manufacturing 
firms in India, they found that daily output per worker declined in 
higher outdoor temperatures, falling 2.7% per 1.8 [deg]F (1 [deg]C) 
increase in daily maximum ambient temperature above 77 [deg]F (25 
[deg]C) (this study was also mentioned above in section 
VIII.I.II.B.I.). Using annual plant-level output data from a nationally 
representative panel of manufacturing plants in India, they found that 
annual plant-level output (measured by value added, defined as the 
difference between total output and the value of intermediate inputs) 
decreased by 2.1% per 1.8 [deg]F (1 [deg]C) increase in the annual 
average of the daily maximum ambient temperature. Under the 
specification of the Cobb-Douglas function, they reported that changes 
in labor input as opposed to capital input explains these declines in 
plant-level output.\130\ Using annual district-level manufacturing 
sector GDP data from a sample of 438 districts in India, they found 
that annual district-level manufacturing output decreased by 3.5% per 
1.8 [deg]F (1[deg]C) increase in the annual average of the daily 
maximum ambient temperature. The authors further noted that the 
magnitude of their estimated effects mirrored the country-level 
estimates of output effects in the literature (country-level studies 
are described in more detail in section VIII.I.II.D.I.b., below), which 
they interpreted as evidence heat exposure affects output through labor 
productivity.
---------------------------------------------------------------------------

    \130\ Assuming the specification of the Cobb-Douglas production 
function, Somanathan et al. (2021) also found that changes in labor 
input (measured by number of full-time workers) as opposed to 
capital input (measured by net value of equipment of machinery at 
the start of each year) explained the negative effect of higher 
temperature on plant-level output.

---------------------------------------------------------------------------

[[Page 71023]]

    Using daily production line-level data from garment factories 
around Bangalore, India, Adhvaryu et al. (2020) found that production 
line efficiency (measured as ratio of realized output to target output) 
decreased in higher outdoor temperatures, by 2.1% for per 1.8 [deg]F (1 
[deg]C) increase in daily average WBGT above 66.2 [deg]F (19 [deg]C). 
They did not find significant effects of higher temperatures on worker 
attendance, providing further support that labor productivity effects 
were likely the reason behind the observed relationship. Using annual 
firm-level data from the annual survey of industrial firms that are 
``above-scale'' (with sales over a certain threshold) in China from 
1998 to 2007 and assuming the specification of the Cobb-Douglas 
function, Zhang et al. (2018) found an inverted U-shaped relationship 
between temperature and total factor productivity (TFP) and output in 
the Chinese manufacturing sector. They found that, relative to a year 
with an extra day of average ambient temperature of 50 [deg]F-60 [deg]F 
(10 [deg]C-15.6 [deg]C), a year with an extra day over 90 [deg]F (32.2 
[deg]C) had lower annual firm-level TFP by 0.56% and lower firm-level 
output (measured by value added, defined as the difference between 
total output and the value of intermediate inputs) by 0.45%. They also 
found that the TFP effects and output effects of temperature are of 
similar magnitude for both labor-intensive and capital-intensive firms, 
suggesting that both labor productivity and capital productivity were 
affected by heat exposure.
    Using the same dataset as Zhang et al. (2018), Chen and Yang (2019) 
found that a 1.8[deg]F (1[deg]C) increase in the average summer 
temperature (3-month average of daily average ambient temperatures for 
months June through August) decreased value added per worker by 3.4% to 
4.5%. They also found two potential channels through which higher 
temperatures reduce output: decrease in firm investment and increase in 
inventory levels.
    Using annual firm-level data on revenue per worker in the 
manufacturing and services sectors from 15 developed and developing 
countries, Nath (2020) found a stronger negative effect of an extra hot 
day (a day with maximum ambient temperature of 104 [deg]F (40 [deg]C) 
relative to a day of 86 [deg]F (30 [deg]C)) on annual revenue per 
worker for poorer countries (i.e., lower purchasing power parity (PPP)-
adjusted GDP per capita). They also found that the decline in revenue 
per worker was driven by changes in both the numerator (annual revenue) 
and denominator (annual employment), where the change in the numerator 
was greater than that of the denominator.
    There are several caveats with studies reporting plant/firm-level 
output effects of heat exposure. First, although some studies 
identified labor productivity as the main mechanism for their findings 
(Somanathan et al., 2021; Adhvaryu et al., 2020; Nath, 2020), the 
literature overall is inconclusive regarding the extent to which the 
effects are driven by labor productivity (versus other channels such as 
labor supply and capital).
    Second, some studies used outdoor heat conditions as a proxy for 
indoor heat conditions to estimate the labor productivity effects of 
heat exposure in indoor work settings. However, indoor heat conditions 
may not be perfectly correlated with outdoor heat conditions, 
especially with the presence of heat-generating lighting and machines 
and the unknown extent of indoor climate controls (Cachon et al., 2012; 
Adhvaryu et al.,2020).\131\
---------------------------------------------------------------------------

    \131\ Using indoor temperature data that was not available 
during the period when labor productivity effects were analyzed and 
was available only afterwards, Adhvaryu et al. (2020) reported a 
high but imperfect pass-through of 79% of outdoor ambient 
temperature to indoor ambient temperature.
---------------------------------------------------------------------------

b. Region-Level Output Effects
    Several studies found economic output effects of heat exposure 
using region-level panel data. Some studies used county-level or State-
level panel data to estimate the effects of heat on economic output. 
Deryugina and Hsiang (2014) used U.S. county-level panel data of annual 
total personal income per capita and daily weather from 1969 to 2011 to 
find that average per-day personal income per capita declines 1.68% per 
1.8 [deg]F (1 [deg]C) increase in daily average ambient temperature 
above 59 [deg]F (15 [deg]C). Behrer and Park (2017) used U.S. county-
level panel data of annual non-agricultural payroll per capita and 
daily weather from 1986 to 2011 to find that an additional hot day (a 
day of daily maximum ambient temperature above 95 [deg]F (35 [deg]C) 
relative to a day of 70 [deg]F-79 [deg]F (21.1 [deg]C-26.1 [deg]C)) 
reduced annual payroll per capita by 0.04%. Colacito et al. (2019) used 
U.S. State-level panel data of State GDP (i.e., gross State product) 
and daily weather to find that annual growth rate of a State's output 
declined by 0.15-0.25 percentage point per 1 [deg]F (0.56 [deg]C) 
increase in the average summer ambient temperature (three-month average 
of daily average ambient temperatures for months July through 
September).
    Some studies used country-level panel data to estimate the effects 
of heat on economic output. Hsiang (2010) found for a panel of 28 
Caribbean-Basin countries from 1970 to 2006 that annual output 
decreased by 2.4% per 1.8 [deg]F (1 [deg]C) increase in the average 
annual ambient temperature and the effects were driven by temperature 
changes during the hottest season (September through November). 
Furthermore, the study highlighted the similarity between their 
estimated output effects of temperature and the worker productivity 
effects of temperature reported in the ``ergonomics and physiology'' 
literature as evidence for labor productivity being an important 
channel underlying the economic effects of heat exposure. Dell et al. 
(2012) found for a panel of 124 countries from 1950 to 2003 that higher 
temperatures affected growth rates as well as level of output, but only 
in poor countries, defined as ``having below-median PPP-adjusted per 
capita GDP in the first year the country enters the dataset.'' They 
found that 1.8 [deg]F (1 [deg]C) higher annual average ambient 
temperature in poor countries was associated with 2.04%p lower annual 
average growth in industrial output (growth in value added in mining, 
manufacturing, construction, electricity, water, and gas sectors). Some 
studies also found a nonlinear effect of temperature on economic 
output, implying that higher temperature negatively affects poor 
countries that tend to be hot and positively affects rich countries 
that tend to be cold (Heal and Park, 2016, p. 356). Heal and Park 
(2013) found for a panel of 134 countries from 1950 to 2006 that the 
response of annual real GDP per capita to annual average ambient 
temperature is nonlinear, that is, an inverted U-shaped response 
peaking at around 59 [deg]F-68 [deg]F (15 [deg]C-20 [deg]C). Burke et 
al. (2015) found for a panel of 166 countries from 1960 to 2010 an 
inverted U-shaped response of annual average GDP per capita to annual 
average temperate peaking at 55.4 [deg]F (13 [deg]C).
    There are several caveats with studies reporting region-level 
output effects of heat exposure.
    First, there is uncertainty regarding the extent to which labor 
productivity alone can explain the decline in output due to heat 
exposure (Lai et al., 2023). On the one hand, several studies 
highlighted labor productivity as an important if not the main channel 
through which heat exposure negatively affects output (e.g., Hsiang, 
2010; Somanathan et al., 2021; Dell et al., 2014). On the other hand, 
due to the less frequent measurements of output (e.g.,

[[Page 71024]]

weekly, monthly, yearly), it is unclear if the results were driven by 
reductions in labor supply, labor productivity, labor demand, capital 
productivity, firm investment, increase in firm costs, or ``some 
combination of all of these'' (Behrer et al., 2021). For example, the 
estimated changes in output could be capturing demand-side factors 
either positively or negatively correlated with temperature (e.g., 
demand for ice cream increases with temperature; demand for outdoor 
recreation decreases with temperature) (Behrer and Park, 2017, p. 16). 
Changes in payroll may also not necessarily capture only changes in 
labor productivity but also capture changes in labor supply and 
increased firm costs (e.g., increased costs due to higher utilization 
of air-conditioning reducing firm profits or net income) (Behrer and 
Park, 2017, p. 13).
    Second, although some of these studies found effects of heat-
exposure on nonagricultural output, these observed associations may be 
in part due to the non-agricultural sectors facing less demand as a 
spillover effect of agricultural yield reductions from the agricultural 
sector (Dell et al., 2012, p. 85; Heal and Park, 2016, p. 9).
II. Studies Borrowing Exposure-Response Functions From Occupational 
Health Literature
    Section VIII.I.II.D.II. discussed studies that directly estimated 
the relationship between heat exposure and economic output and tried to 
uncover the underlying the potential mechanisms such as labor 
productivity.
    This section discusses other studies that borrowed heat exposure-
work capacity response (exposure-response) functions that were derived 
by existing studies in the occupational health literature. Applying 
these functions to the worker population of interest (e.g., outdoor 
workers nationwide), these studies derived economy-wide labor 
productivity loss and the associated economic cost in terms of lost 
wages or lost output.
    As discussed in the section VIII.I.II.B.I.a., exposure-response 
functions in the occupational health literature fall into two groups. 
The first group of exposure-response functions are based on empirical 
data (e.g., Hothaps function derived in Kjellstrom et al., 2014; PWC 
function derived in Foster et al., 2021). The second group of exposure-
response functions are based on recommended work-rest ratios in 
existing work-rest guidelines by NIOSH, ACGIH, and ISO (e.g., 
Kjellstrom et al., 2009b; Dunne et al., 2013).
    These empirically-derived or guideline-based exposure-response 
functions from the occupational health literature were applied by 
several studies to macroeconomic data and models to estimate the 
economic impact of heat exposure. These studies fall into three groups: 
the first group of studies (e.g., Orlov et al., 2019; Morabito et al., 
2020, Nelson et al., 2024) borrowed the empirically-derived functions; 
the second group of studies (e.g., DARA, 2012; Vanos et al., 2019; 
Takakura et al., 2017; Atlantic Council, 2022; de Lima et al., 2021) 
borrowed the guideline-based functions ; and the third group of studies 
(e.g., Kjellstrom et al., 2018; ILO, 2019; Atlantic Council, 2021; 
Romanello et al., 2023; Dasgupta et al., 2021) borrowed and combined 
empirically-derived functions with the guideline-based functions.
    There are some caveats with studies relying on existing exposure-
response functions to estimate the economic impact of heat exposure. 
First, empirically-derived exposure-response functions are context-
specific (e.g., the Hothaps function is based on data from acclimatized 
outdoor workers in hotter regions; the PWC function is based on data 
from unacclimatized young adults in indoor climatic chambers). Studies 
relying on empirically-derived functions are effectively assuming that 
the average worker behaves as predicted by these context-specific 
functions.
    Second, existing work-rest guidelines were designed to increase 
work-rest ratios to minimize heat-related illnesses (Borg et al., 2021, 
p. 12) and were never intended to estimate the casual effect of heat 
exposure on work capacity (Foster et al., 2021, p. 1216). Studies 
relying on guideline-based exposure-response functions effectively 
assumed that the average worker behaves according to the recommended 
work-rest ratios. Therefore, these studies reported larger economic 
costs associated with lost work capacity from heat than what is 
reported by empirical studies (Borg et al., 2021, p. 12).
E. Worker Utility
    Higher temperatures not only reduce labor supply and labor 
productivity, but also ``cause discomfort'' (Graff Zivin and Neidell, 
2014, p. 1) or ``make work more arduous'' for those able to work (Rode 
et al., 2022, p. 3). Several studies have indeed found evidence that 
workers dislike working in the heat, suggesting the negative effects of 
heat exposure on worker utility.
    Some studies found evidence of the negative effect of heat exposure 
on worker utility based on worker surveys. Krishnamurthy et al. (2017) 
reported that about a quarter of surveyed steel factory workers in 
India reported social impacts on their personal lives attributable to 
occupational heat stress. Reported impacts include the time and 
resources spent coping with the heat and the excessive exhaustion 
impeding the engagement in family and social interactions outside work. 
Such responses highlight a potential mechanism through which heat 
increases disutility of labor. LoPalo (2023) also found that in higher 
temperatures, household survey interviewers worked longer hours (by 
starting earlier in the day and spending more time on each interview) 
to avoid working during hotter times of the day and to also meet their 
daily target number of completed interviews, suggesting a loss in the 
welfare of the interviewer through a loss of leisure hours.
    Some workers even reported intentions to change jobs due to heat 
exposure, as expressed in an online survey conducted by Zander et al. 
(2015), showing that 27% of the surveyed Australian workers exposed to 
heat said they would eventually change jobs because of heat at their 
workplace. In contrast, only 8% of the surveyed workers who are 
sometimes exposed to heat said they considered this option, and those 
rarely exposed only expressed this 2% of the time. On the other hand, 
Kahn (2016) highlighted an example of market failure where employers 
having monopsony power in local labor markets can still hire workers at 
low wages for ``unpleasant'' jobs exposed to heat without adequate 
worker protection measures in place, such as large warehouses without 
air-conditioning (p. 171).
    Interpreting their empirically-estimated decline in labor supply in 
higher temperatures as workers choosing to work less in the heat at the 
cost of foregoing pay (discussed above in section VIII.I.II.A.), Rode 
et al. (2022) derived the willingness-to-pay to avoid the increased 
disutility of working in higher temperatures (defined as the increase 
in the wage rate that is needed to offset the increased disutility of 
labor).
F. Summary of Section VIII.I.II
    The literature documents effects of heat exposure on outcomes with 
economic consequences. Effects are observed in a variety of 
occupational settings, suggesting that the effects of heat exposure are 
widespread across a broad range of tasks that rely on physical or 
cognitive skills and that heat exposure affects workers in both indoor 
and outdoor settings. In particular, the literature recognizes labor 
productivity as a potential channel through which

[[Page 71025]]

heat exposure affects economic outcomes.
III. Workplace Characteristics and Labor Productivity Effects of Heat 
Exposure
    The literature's varying estimates of the effect of heat exposure 
on labor productivity could be attributed to differences in workplace 
characteristics, such as incentive structures and availability of 
adaptation measures (Park et al., 2021, p. 8, footnote 13). These 
workplace characteristics should be considered when interpreting the 
variation in estimates of the labor productivity-related effects of 
heat exposure in the literature (Heal and Park, 2016, p. 350). This 
section focuses on studies that reported labor productivity (discussed 
in section VIII.I.II.B., above) but also includes some studies that are 
potentially related to labor productivity, such as studies on mental 
performance (discussed in section VIII.I.II.C., above) or studies on 
economic output effects that are potentially linked to labor 
productivity (discussed in section VIII.I.II.D.I., above).
A. Incentive Structures
    Depending on the physical and behavioral aspects of the workplace, 
workers and management could be incentivized to change the level of 
effort, affecting the estimated labor productivity effect of heat 
exposure. Workplace factors that affect incentives include wage 
structure (e.g., piece-rate, hourly rate, annual salary), management 
techniques, mechanization, and other factors not accounted for by 
laboratory studies (Somanathan et al., 2021).
    One of the most analyzed workplace factors in the literature is 
piece-rate pay. Quiller et al. (2017) found null effects of heat on 
labor productivity (measure by weight of fruit bins collected per hour) 
for a sample of piece-rate paid tree fruit harvesters in Washington 
State, after adjusting for confounders such as price paid per bin and 
shift duration. Mitchell et al. (2018) used accelerometer data from 
farm workers in California to find, even after adjusting for 
confounders, negative effects of heat on labor productivity (measured 
by physical activity intensity, i.e., step counts per minute, converted 
into metabolic equivalents) and that the effects were less negative for 
male workers paid by piece-rate. Such small or zero labor productivity 
effects could reflect compensatory effort on part of workers 
incentivized to be as productive as possible, the health and safety 
consequences of which should not be overlooked (Park et al., 2021, p. 
8, footnote 13). Piece-rate workers being incentivized to work fast and 
take few rest breaks even under heat exposure have been evidenced in 
focus group discussions with U.S. farmworkers (Wadsworth et al., 2019; 
Lam et al., 2013).
    Several studies also found that, due to physiological constraints, 
piece-rate workers cannot increase their effort infinitely in the heat. 
Stevens (2017) found that higher piece-rates induced increases in labor 
productivity of blueberry pickers in California at ambient temperatures 
below 60 [deg]F but not at higher temperatures. Masuda et al. (2021) 
also found in a field experiment in Indonesia that increasing the 
piece-rate did not increase effort, as measured by the proportion of 
time spent in moderate and vigorous activity through an accelerometer. 
This evidence is consistent with workers facing binding physiological 
constraints that prevent them from exerting additional effort in 
response to higher piece-rates at high temperatures.
    In their findings of the labor productivity effects of 
environmental conditions, some studies also addressed the possibility 
that piece-rate workers' labor productivity could decline further if 
they are subject to State minimum wage laws (e.g., Stevens, 2017 in the 
context of heat; Graff Zivin and Neidell, 2012 in the context of ozone 
pollution). Hypothetically, compared to when not guaranteed a minimum 
wage, higher temperatures could lead piece-rate workers to exert less 
effort and therefore result in greater decline in labor productivity.
    From data on Demographic and Health Surveys (DHS) interviewers from 
46 developing countries, LoPalo (2023) found nuanced adjustments in 
effort by DHS interviewers. DHS interviewers are paid a fixed daily 
wage (i.e., not piece-rate) but are still monitored by supervisors to 
ensure they meet the target number of completed interviews. Under this 
contractual structure, higher temperatures result in lower labor 
productivity in terms of number of completed interviews per hour--
interviewers are able to maintain the same daily number of completed 
interviews but at the cost of a longer shift from trying to avoid 
working in the heat (by starting work earlier and spending more time on 
each interview). They also found that data quality problems (e.g., 
missing responses) become more frequent on hotter days, suggesting that 
workers shift effort away from production quality, which is less 
noticeable to supervisors, to production quantity, which is more 
noticeable.
B. Adaptation
    Regarding adaptation measures \132\ alleviating the negative labor 
productivity-related effects of heat exposure, the most analyzed in the 
literature are the adoption of engineering controls. Using microdata 
from selected manufacturing plants in India, Somanathan et al. (2021) 
found that climate controls in the workplace eliminated declines in 
labor productivity due to elevated temperatures but did not eliminate 
declines in labor supply (based on worker attendance records). The 
authors conjectured declines in labor supply persisted despite climate-
controlled conditions at work because workers presumably continued to 
be exposed to high temperature at home and outside. Adhvaryu et al. 
(2020) found in line-level production data from Indian garment 
factories that the introduction of LED lighting (that replaced compact 
fluorescent lighting which generates more heat) helped to alleviate the 
negative effect of high outdoor temperatures on production line 
efficiency. Using panel data of individual-level cognitive test scores 
administered at respondents' homes for adults as well as children as 
part of a

[[Page 71026]]

nationally representative biennial longitudinal survey in China, Zhang 
et al. (2024) found that their estimated effect of higher temperatures 
on math test scores was less negative by 36.6% for households with air-
conditioning.
---------------------------------------------------------------------------

    \132\ Some studies reporting economic output effects (discussed 
above in section VIII.I.II.D.I.) found heterogeneous effects of 
temperature depending on regional climate. They found that hotter 
regions displayed smaller declines in output to higher temperatures, 
suggesting that their findings could reflect adaptation in these 
regions. For example, Chen and Yang (2019) found lower sensitivity 
in the response of value added per worker to higher temperatures 
among plants associated with a single firm in warmer locations in 
China and raised the possibility of adaptation measures such as 
avoiding work during hottest times of the day playing a role. Zhang 
et al. (2023) used Chinese province-level panel data of construction 
labor productivity (defined as the ratio of the total value of 
output to the number of laborers in construction enterprises) and 
quarterly weather to find an inverted U-shaped relationship between 
quarterly construction labor productivity and quarterly average 
ambient temperature that peaked at higher temperatures in hotter 
regions (79.25 [deg]F (26.25 [deg]C) in eastern regions versus 68 
[deg]F (20 [deg]C) for central and western regions). They 
conjectured that workers in hotter regions are more adapted to high 
temperatures so that the peak temperature after which their labor 
productivity started to decline was higher. Behrer and Park (2017) 
used U.S. county-level panel data of annual non-agricultural payroll 
per capita and daily weather to find that the negative effect of an 
additional hot day on annual payroll per capita was smaller in 
hotter counties (in the top quartile of the U.S. average ambient 
temperature distribution). They suggested that such attenuated 
effects of heat exposure in hotter regions can be explained by the 
larger presence of air-conditioning in these regions, as evidenced 
by region-level data on percentage of households and commercial 
buildings with air-conditioning. Heal and Park (2013) also found in 
country-level panel data that annual real GDP per capita was less 
negatively affected by heat exposure in hot countries where air-
conditioning was more prevalent.
---------------------------------------------------------------------------

    Some studies that found negative effects of heat exposure on 
athletic performance also evaluated the effects of 
acclimatization.\133\ Using athlete-competition level panel data on 
collegiate track and field performances, Sexton et al. (2022) found 
that hotter average ambient temperatures at the home institution in the 
week prior to the competition (``precompetition temperatures'') 
mitigated performance loss from high competition temperatures. They 
reported that for hot competitions with daily average ambient 
temperatures exceeding 70 [deg]F (21.1 [deg]C), performance loss from 
high competition temperature decreases by 1.6%-3.5% per 1.8 [deg]F (1 
[deg]C) increase in temperature difference between the precompetition 
and competition temperatures. On the other hand, using athlete-contest 
level panel data of Chinese professional archers, Qiu and Zhao (2022) 
did not find evidence that heat exposure within several months prior to 
a competition improved competition performance in the heat. Qiu and 
Zhao (2022) however found evidence of benefits of ``longer-term 
acclimatization''; athletes that trained in the southern provinces of 
China, where hot days are more common, were less affected by heat 
exposure than those trained in the northern provinces. From player-
match level panel data of professional tennis players, Burke et al. 
(2023) also did not find evidence of benefits of acclimatization; 
players who played their previous match in higher temperatures did 
worse in their current match. Burke et al. (2023) also did not find 
evidence of benefits of ``long-term exposure to heat''; players born or 
residing in locations of higher temperatures did not appear to be less 
affected by higher temperatures during the match. Burke et al. (2023) 
conjectured that their lack of evidence of benefits of acclimatization 
compared to Sexton et al. (2022) could be because their proxy of 
acclimatization captured players playing an actual match in high 
temperatures, while acclimatization could be ``more effective during 
repeated episodes of more restrained effort, as emphasized in most 
sports heat acclimatization protocols (p. 12).''
---------------------------------------------------------------------------

    \133\ In the context of labor supply, Graff Zivin and Neidell 
(2014) found that their estimated negative effect of heat exposure 
on labor supply was smaller in August compared to June, suggesting 
that workers became less sensitive to heat exposure as higher 
temperatures became more common. As another test for effects of 
acclimatization, they also found that the negative effect of heat 
exposure on labor supply was smaller in ``warm counties'' compared 
to ``cool counties'' (defined as counties in the highest and lowest 
third of historical July-August temperatures, respectively), 
although the estimated difference was not statistically significant.
---------------------------------------------------------------------------

C. Summary of Section VIII.I.III
    To summarize, workplace incentives and availability of adaptation 
measures affect the estimated labor productivity-related effects of 
heat exposure documented in the literature.
IV. Conclusion
    The available literature on the effects of heat exposure on non-
health outcomes suggests that heat exposure can lead to decreased labor 
productivity as well as to reduced labor supply, mental performance, 
economic output, and worker utility. It also indicates that existing 
workplace characteristics such as incentive structures and adoption of 
adaptation measures should be considered when evaluating these negative 
non-health consequences of heat exposure.

J. Appendix C. Heat Exposure Methodology Used in Distributional 
Analysis

    The following steps were taken to quantify the fraction of workers 
benefiting from the proposed standard in different demographic and 
economic categories.
I. ACS Data Processing
    The analysis uses data from the Census Bureau's American Community 
Survey (ACS) from 2018 to 2022 (Ruggles et al., 2024). 2022 is the most 
recent available year of ACS data. ACS data provide worker-level 
information on demographic and economic characteristics. The following 
demographic and economic characteristics are recorded in the ACS: age; 
race and ethnicity; sex; total family income; industry; occupation; the 
presence of a disability related to cognition, physical activity, 
mobility, self-care, vision, or hearing; and U.S. citizenship. In 
addition, LGBTQ+ status was inferred from cases where an individual was 
living (married or unmarried) with a same-sex partner.
    Only data for employed workers 16 years or older was used. The ACS 
variables were processed as follows. Age was grouped into 10-year bins 
(with age 65+ as the top bin). Race and ethnicity variables were coded 
into the groups Hispanic, Black, Asian (including Pacific Islander), 
White (non-Hispanic), and other groups. Total family income was 
converted into deciles. Presence of a disability was coded into a 
single indicator variable for the presence of any disability. Sex and 
the presence of a same-sex partner required no further processing.
II. Merging ACS Data With Heat Exposure Measures
    Calculations of workers likely to be affected by the proposed 
standard from Section VIII.B., Profile of Affected Industries were next 
merged with the ACS data. Fractions of workers exposed to heat by 
industry and occupation was used. In Section VIII.B., Profile of 
Affected Industries, exposure was calculated at the 4-digit NAICS level 
and with detailed (6-digit) SOC codes. To consistently merge with the 
ACS, these affected workers were aggregated to the 2-digit NAICS code 
by 4-digit SOC code level.\134\ The aggregation was done by calculating 
weighted average fraction of workers exposed to heat in outdoor 
settings and indoor settings (separately due to process heat or 
inadequate climate control) in each industry-occupation pair. The 
weights were number of workers in each 4-digit by 6-digit category, as 
calculated in Section VIII.B., Profile of Affected Industries. The 
worker-level ACS data were then merged with the industry-by-occupation 
exposure fractions.
---------------------------------------------------------------------------

    \134\ ACS includes 4-digit NAICS codes and detailed (6-digit) 
SOC codes for some industries and occupations. However, given that 
ACS uses different industry and occupation definitions than NAICS 
and SOC, many industries and occupations are only consistently coded 
at the 2- or 4-digit level respectively. For example, in the ACS, 
all construction workers are only classified at the 2-digit NAICS 
level (NAICS 23). Aggregation to the 2-digit NAICS code and 4-digit 
SOC code level ensures consistency across workers.
---------------------------------------------------------------------------

III. Calculate Exposure by Demographic and Economic Group
    For each dimension of heterogeneity described above, the average 
share of exposed workers was calculated. The average exposure was 
weighted by the person-weights in the ACS to generate representative 
values for the U.S.
    The result is a figure like figure VIII.J.1. shown below. The 
figure shows the percent of workers exposed to outdoor heat across 
total family income deciles. The deciles are given on the x-axis along 
with the range of income they represent, and the y-axis is the 
percentage of workers. The figure VIII.J.1. shows that about 13 percent 
of workers in low-income deciles are exposed to outdoor heat on the job 
while about 7 percent of workers in the highest income decile are 
exposed.

[[Page 71027]]

[GRAPHIC] [TIFF OMITTED] TP30AU24.029

K. Appendix D. Definitions of Core Industry Categories Used in Cost 
Analysis

                      Table VIII.K.1--In-Scope Core Industries by Core Industry Categories
----------------------------------------------------------------------------------------------------------------
            Core industry category               4-Digit NAICS                     NAICS title
----------------------------------------------------------------------------------------------------------------
Agriculture, Forestry, and Fishing............          111100  Oilseed and Grain Farming.
Agriculture, Forestry, and Fishing............          111200  Vegetable and Melon Farming.
Agriculture, Forestry, and Fishing............          111300  Fruit and Tree Nut Farming.
Agriculture, Forestry, and Fishing............          111400  Greenhouse, Nursery, and Floriculture
                                                                 Production.
Agriculture, Forestry, and Fishing............          111900  Other Crop Farming.
Agriculture, Forestry, and Fishing............          112100  Cattle Ranching and Farming.
Agriculture, Forestry, and Fishing............          112200  Hog and Pig Farming.
Agriculture, Forestry, and Fishing............          112300  Poultry and Egg Production.
Agriculture, Forestry, and Fishing............          112400  Sheep and Goat Farming.
Agriculture, Forestry, and Fishing............          112500  Aquaculture.
Agriculture, Forestry, and Fishing............          112900  Other Animal Production.
Agriculture, Forestry, and Fishing............          113100  Timber Tract Operations.
Agriculture, Forestry, and Fishing............          113200  Forest Nurseries and Gathering of Forest
                                                                 Products.
Agriculture, Forestry, and Fishing............          113300  Logging.
Agriculture, Forestry, and Fishing............          114100  Fishing.
Agriculture, Forestry, and Fishing............          114200  Hunting and Trapping.
Agriculture, Forestry, and Fishing............          115100  Support Activities for Crop Production.
Agriculture, Forestry, and Fishing............          115200  Support Activities for Animal Production.
Agriculture, Forestry, and Fishing............          115300  Support Activities for Forestry.
Building Materials and Equipment Suppliers....          423300  Lumber and Other Construction Materials Merchant
                                                                 Wholesalers.
Building Materials and Equipment Suppliers....          423700  Hardware, and Plumbing and Heating Equipment and
                                                                 Supplies Merchant Wholesalers.
Building Materials and Equipment Suppliers....          423900  Miscellaneous Durable Goods Merchant
                                                                 Wholesalers.
Building Materials and Equipment Suppliers....          444100  Building Material and Supplies Dealers.
Building Materials and Equipment Suppliers....          532400  Commercial and Industrial Machinery and
                                                                 Equipment Rental and Leasing.
Commercial Kitchens...........................          311800  Bakeries and Tortilla Manufacturing.
Commercial Kitchens...........................          722300  Special Food Services.
Commercial Kitchens...........................          722400  Drinking Places (Alcoholic Beverages).
Commercial Kitchens...........................          722500  Restaurants and Other Eating Places.
Construction..................................          236100  Residential Building Construction.
Construction..................................          236200  Nonresidential Building Construction.
Construction..................................          237100  Utility System Construction.
Construction..................................          237200  Land Subdivision.
Construction..................................          237300  Highway, Street, and Bridge Construction.
Construction..................................          237900  Other Heavy and Civil Engineering Construction.
Construction..................................          238100  Foundation, Structure, and Building Exterior
                                                                 Contractors.
Construction..................................          238200  Building Equipment Contractors.
Construction..................................          238300  Building Finishing Contractors.

[[Page 71028]]

 
Construction..................................          238900  Other Specialty Trade Contractors.
Construction..................................          541300  Architectural, Engineering, and Related
                                                                 Services.
Drycleaning and Commercial Laundries..........          812300  Drycleaning and Laundry Services.
Landscaping and Facilities Support............          561200  Facilities Support Services.
Landscaping and Facilities Support............          561700  Services to Buildings and Dwellings.
Landscaping and Facilities Support............          561900  Other Support Services.
Landscaping and Facilities Support............          812200  Death Care Services.
Landscaping and Facilities Support............          812900  Other Personal Services.
Maintenance and Repair........................          811100  Automotive Repair and Maintenance.
Maintenance and Repair........................          811300  Commercial and Industrial Machinery and
                                                                 Equipment (except Automotive and Electronic)
                                                                 Repair and Maintenance.
Maintenance and Repair........................          811400  Personal and Household Goods Repair and
                                                                 Maintenance.
Manufacturing.................................          311100  Animal Food Manufacturing.
Manufacturing.................................          311200  Grain and Oilseed Milling.
Manufacturing.................................          311300  Sugar and Confectionery Product Manufacturing.
Manufacturing.................................          311400  Fruit and Vegetable Preserving and Specialty
                                                                 Food Manufacturing.
Manufacturing.................................          311500  Dairy Product Manufacturing.
Manufacturing.................................          311600  Animal Slaughtering and Processing.
Manufacturing.................................          311700  Seafood Product Preparation and Packaging.
Manufacturing.................................          311900  Other Food Manufacturing.
Manufacturing.................................          312100  Beverage Manufacturing.
Manufacturing.................................          312200  Tobacco Manufacturing.
Manufacturing.................................          313100  Fiber, Yarn, and Thread Mills.
Manufacturing.................................          313200  Fabric Mills.
Manufacturing.................................          313300  Textile and Fabric Finishing and Fabric Coating
                                                                 Mills.
Manufacturing.................................          314100  Textile Furnishings Mills.
Manufacturing.................................          314900  Other Textile Product Mills.
Manufacturing.................................          315100  Apparel Knitting Mills.
Manufacturing.................................          315200  Cut and Sew Apparel Manufacturing.
Manufacturing.................................          315900  Apparel Accessories and Other Apparel
                                                                 Manufacturing.
Manufacturing.................................          316100  Leather and Hide Tanning and Finishing.
Manufacturing.................................          316200  Footwear Manufacturing.
Manufacturing.................................          316900  Other Leather and Allied Product Manufacturing.
Manufacturing.................................          321100  Sawmills and Wood Preservation.
Manufacturing.................................          321200  Veneer, Plywood, and Engineered Wood Product
                                                                 Manufacturing.
Manufacturing.................................          321900  Other Wood Product Manufacturing.
Manufacturing.................................          322100  Pulp, Paper, and Paperboard Mills.
Manufacturing.................................          322200  Converted Paper Product Manufacturing.
Manufacturing.................................          323100  Printing and Related Support Activities.
Manufacturing.................................          324100  Petroleum and Coal Products Manufacturing.
Manufacturing.................................          325100  Basic Chemical Manufacturing.
Manufacturing.................................          325200  Resin, Synthetic Rubber, and Artificial and
                                                                 Synthetic Fibers and Filaments Manufacturing.
Manufacturing.................................          325300  Pesticide, Fertilizer, and Other Agricultural
                                                                 Chemical Manufacturing.
Manufacturing.................................          325400  Pharmaceutical and Medicine Manufacturing.
Manufacturing.................................          325500  Paint, Coating, and Adhesive Manufacturing.
Manufacturing.................................          325600  Soap, Cleaning Compound, and Toilet Preparation
                                                                 Manufacturing.
Manufacturing.................................          325900  Other Chemical Product and Preparation
                                                                 Manufacturing.
Manufacturing.................................          326100  Plastics Product Manufacturing.
Manufacturing.................................          326200  Rubber Product Manufacturing.
Manufacturing.................................          327100  Clay Product and Refractory Manufacturing.
Manufacturing.................................          327200  Glass and Glass Product Manufacturing.
Manufacturing.................................          327300  Cement and Concrete Product Manufacturing.
Manufacturing.................................          327400  Lime and Gypsum Product Manufacturing.
Manufacturing.................................          327900  Other Nonmetallic Mineral Product Manufacturing.
Manufacturing.................................          331100  Iron and Steel Mills and Ferroalloy
                                                                 Manufacturing.
Manufacturing.................................          331200  Steel Product Manufacturing from Purchased
                                                                 Steel.
Manufacturing.................................          331300  Alumina and Aluminum Production and Processing.
Manufacturing.................................          331400  Nonferrous Metal (except Aluminum) Production
                                                                 and Processing.
Manufacturing.................................          331500  Foundries.
Manufacturing.................................          332100  Forging and Stamping.
Manufacturing.................................          332200  Cutlery and Handtool Manufacturing.
Manufacturing.................................          332300  Architectural and Structural Metals
                                                                 Manufacturing.
Manufacturing.................................          332400  Boiler, Tank, and Shipping Container
                                                                 Manufacturing.
Manufacturing.................................          332500  Hardware Manufacturing.
Manufacturing.................................          332600  Spring and Wire Product Manufacturing.
Manufacturing.................................          332700  Machine Shops; Turned Product; and Screw, Nut,
                                                                 and Bolt Manufacturing.
Manufacturing.................................          332800  Coating, Engraving, Heat Treating, and Allied
                                                                 Activities.
Manufacturing.................................          332900  Other Fabricated Metal Product Manufacturing.
Manufacturing.................................          333100  Agriculture, Construction, and Mining Machinery
                                                                 Manufacturing.
Manufacturing.................................          333200  Industrial Machinery Manufacturing.

[[Page 71029]]

 
Manufacturing.................................          333300  Commercial and Service Industry Machinery
                                                                 Manufacturing.
Manufacturing.................................          333400  Ventilation, Heating, Air-Conditioning, and
                                                                 Commercial Refrigeration Equipment
                                                                 Manufacturing.
Manufacturing.................................          333500  Metalworking Machinery Manufacturing.
Manufacturing.................................          333600  Engine, Turbine, and Power Transmission
                                                                 Equipment Manufacturing.
Manufacturing.................................          333900  Other General Purpose Machinery Manufacturing.
Manufacturing.................................          335100  Electric Lighting Equipment Manufacturing.
Manufacturing.................................          335200  Household Appliance Manufacturing.
Manufacturing.................................          335300  Electrical Equipment Manufacturing.
Manufacturing.................................          335900  Other Electrical Equipment and Component
                                                                 Manufacturing.
Manufacturing.................................          336100  Motor Vehicle Manufacturing.
Manufacturing.................................          336200  Motor Vehicle Body and Trailer Manufacturing.
Manufacturing.................................          336300  Motor Vehicle Parts Manufacturing.
Manufacturing.................................          336400  Aerospace Product and Parts Manufacturing.
Manufacturing.................................          336500  Railroad Rolling Stock Manufacturing.
Manufacturing.................................          336600  Ship and Boat Building.
Manufacturing.................................          336900  Other Transportation Equipment Manufacturing.
Manufacturing.................................          337100  Household and Institutional Furniture and
                                                                 Kitchen Cabinet Manufacturing.
Manufacturing.................................          337200  Office Furniture (including Fixtures)
                                                                 Manufacturing.
Manufacturing.................................          337900  Other Furniture Related Product Manufacturing.
Manufacturing.................................          339100  Medical Equipment and Supplies Manufacturing.
Manufacturing.................................          339900  Other Miscellaneous Manufacturing.
Oil and Gas...................................          211100  Oil and Gas Extraction.
Oil and Gas...................................          213100  Support Activities for Mining.
Oil and Gas...................................          486100  Pipeline Transportation of Crude Oil.
Oil and Gas...................................          486200  Pipeline Transportation of Natural Gas.
Oil and Gas...................................          486900  Other Pipeline Transportation.
Postal and Delivery Services..................          491100  Postal Service.
Postal and Delivery Services..................          492100  Couriers and Express Delivery Services.
Postal and Delivery Services..................          492200  Local Messengers and Local Delivery.
Recreation and Amusement......................          711200  Spectator Sports.
Recreation and Amusement......................          713100  Amusement Parks and Arcades.
Recreation and Amusement......................          713900  Other Amusement and Recreation Industries.
Recreation and Amusement......................          721200  RV (Recreational Vehicle) Parks and Recreational
                                                                 Camps.
Sanitation and Waste Removal..................          562100  Waste Collection.
Sanitation and Waste Removal..................          562200  Waste Treatment and Disposal.
Sanitation and Waste Removal..................          562900  Remediation and Other Waste Management Services.
Telecommunications............................          517100  Wired and Wireless Telecommunications (except
                                                                 Satellite).
Telecommunications............................          517400  Satellite Telecommunications.
Telecommunications............................          517800  All Other Telecommunications.
Temporary Help Services.......................          561300  Employment Services.
Transportation................................          481100  Scheduled Air Transportation.
Transportation................................          481200  Nonscheduled Air Transportation.
Transportation................................          482100  Rail Transportation.
Transportation................................          483100  Deep Sea, Coastal, and Great Lakes Water
                                                                 Transportation.
Transportation................................          483200  Inland Water Transportation.
Transportation................................          484100  General Freight Trucking.
Transportation................................          484200  Specialized Freight Trucking.
Transportation................................          485100  Urban Transit Systems.
Transportation................................          485900  Other Transit and Ground Passenger
                                                                 Transportation.
Transportation................................          488100  Support Activities for Air Transportation.
Transportation................................          488200  Support Activities for Rail Transportation.
Transportation................................          488300  Support Activities for Water Transportation.
Transportation................................          488400  Support Activities for Road Transportation.
Transportation................................          488900  Other Support Activities for Transportation.
Utilities.....................................          221100  Electric Power Generation, Transmission and
                                                                 Distribution.
Utilities.....................................          221200  Natural Gas Distribution.
Utilities.....................................          221300  Water, Sewage and Other Systems.
Warehousing...................................          493100  Warehousing and Storage.
----------------------------------------------------------------------------------------------------------------


   Table VIII.K.2--In-Scope Non-Core Industries Used in Cost Analysis
------------------------------------------------------------------------
     4-Digit NAICS                         NAICS title
------------------------------------------------------------------------
334100                   Computer and Peripheral Equipment
                          Manufacturing.
334200                   Communications Equipment Manufacturing.
334300                   Audio and Video Equipment Manufacturing.
334400                   Semiconductor and Other Electronic Component
                          Manufacturing.
334500                   Navigational, Measuring, Electromedical, and
                          Control Instruments Manufacturing.
334600                   Manufacturing and Reproducing Magnetic and
                          Optical Media.

[[Page 71030]]

 
423100                   Motor Vehicle and Motor Vehicle Parts and
                          Supplies Merchant Wholesalers.
423200                   Furniture and Home Furnishing Merchant
                          Wholesalers.
423400                   Professional and Commercial Equipment and
                          Supplies Merchant Wholesalers.
423500                   Metal and Mineral (except Petroleum) Merchant
                          Wholesalers.
423600                   Household Appliances and Electrical and
                          Electronic Goods Merchant Wholesalers.
423800                   Machinery, Equipment, and Supplies Merchant
                          Wholesalers.
424100                   Paper and Paper Product Merchant Wholesalers.
424200                   Drugs and Druggists' Sundries Merchant
                          Wholesalers.
424300                   Apparel, Piece Goods, and Notions Merchant
                          Wholesalers.
424400                   Grocery and Related Product Merchant
                          Wholesalers.
424500                   Farm Product Raw Material Merchant Wholesalers.
424600                   Chemical and Allied Products Merchant
                          Wholesalers.
424700                   Petroleum and Petroleum Products Merchant
                          Wholesalers.
424800                   Beer, Wine, and Distilled Alcoholic Beverage
                          Merchant Wholesalers.
424900                   Miscellaneous Nondurable Goods Merchant
                          Wholesalers.
425100                   Wholesale Trade Agents and Brokers.
441100                   Automobile Dealers.
441200                   Other Motor Vehicle Dealers.
441300                   Automotive Parts, Accessories, and Tire
                          Retailers.
444200                   Lawn and Garden Equipment and Supplies
                          Retailers.
445100                   Grocery and Convenience Retailers.
445200                   Specialty Food Retailers.
445300                   Beer, Wine, and Liquor Retailers.
449100                   Furniture and Home Furnishings Retailers.
449200                   Electronics and Appliance Retailers.
455100                   Department Stores.
455200                   Warehouse Clubs, Supercenters, and Other
                          General Merchandise Retailers.
456100                   Health and Personal Care Retailers.
457100                   Gasoline Stations.
457200                   Fuel Dealers.
458100                   Clothing and Clothing Accessories Retailers.
458200                   Shoe Retailers.
458300                   Jewelry, Luggage, and Leather Goods Retailers.
459100                   Sporting Goods, Hobby, and Musical Instrument
                          Retailers.
459200                   Book Retailers and News Dealers.
459300                   Florists.
459400                   Office Supplies, Stationery, and Gift
                          Retailers.
459500                   Used Merchandise Retailers.
459900                   Other Miscellaneous Retailers.
485200                   Interurban and Rural Bus Transportation.
485300                   Taxi and Limousine Service.
485400                   School and Employee Bus Transportation.
485500                   Charter Bus Industry.
487100                   Scenic and Sightseeing Transportation, Land.
487200                   Scenic and Sightseeing Transportation, Water.
487900                   Scenic and Sightseeing Transportation, Other.
488500                   Freight Transportation Arrangement.
512100                   Motion Picture and Video Industries.
512200                   Sound Recording Industries.
513100                   Newspaper, Periodical, Book, and Directory
                          Publishers.
513200                   Software Publishers.
516100                   Radio and Television Broadcasting Stations.
516200                   Media Streaming Distribution Services, Social
                          Networks, and Other Media Networks and Content
                          Providers.
518200                   Computing Infrastructure Providers, Data
                          Processing, Web Hosting, and Related Services.
519200                   Web Search Portals, Libraries, Archives, and
                          Other Information Services.
521100                   Monetary Authorities-Central Bank.
522100                   Depository Credit Intermediation.
522200                   Nondepository Credit Intermediation.
522300                   Activities Related to Credit Intermediation.
523100                   Securities and Commodity Contracts
                          Intermediation and Brokerage.
523200                   Securities and Commodity Exchanges.
523900                   Other Financial Investment Activities.
524100                   Insurance Carriers.
524200                   Agencies, Brokerages, and Other Insurance
                          Related Activities.
525100                   Insurance and Employee Benefit Funds.
525900                   Other Investment Pools and Funds.
531100                   Lessors of Real Estate.
531200                   Offices of Real Estate Agents and Brokers.
531300                   Activities Related to Real Estate.
532100                   Automotive Equipment Rental and Leasing.
532200                   Consumer Goods Rental.
532300                   General Rental Centers.

[[Page 71031]]

 
533100                   Lessors of Nonfinancial Intangible Assets
                          (except Copyrighted Works).
541100                   Legal Services.
541200                   Accounting, Tax Preparation, Bookkeeping, and
                          Payroll Services.
541400                   Specialized Design Services.
541500                   Computer Systems Design and Related Services.
541600                   Management, Scientific, and Technical
                          Consulting Services.
541700                   Scientific Research and Development Services.
541800                   Advertising, Public Relations, and Related
                          Services.
541900                   Other Professional, Scientific, and Technical
                          Services.
551100                   Management of Companies and Enterprises.
561100                   Office Administrative Services.
561400                   Business Support Services.
561500                   Travel Arrangement and Reservation Services.
561600                   Investigation and Security Services.
611100                   Elementary and Secondary Schools.
611200                   Junior Colleges.
611300                   Colleges, Universities, and Professional
                          Schools.
611400                   Business Schools and Computer and Management
                          Training.
611500                   Technical and Trade Schools.
611600                   Other Schools and Instruction.
611700                   Educational Support Services.
621100                   Offices of Physicians.
621200                   Offices of Dentists.
621300                   Offices of Other Health Practitioners.
621400                   Outpatient Care Centers.
621500                   Medical and Diagnostic Laboratories.
621600                   Home Health Care Services.
621900                   Other Ambulatory Health Care Services.
622100                   General Medical and Surgical Hospitals.
622200                   Psychiatric and Substance Abuse Hospitals.
622300                   Specialty (except Psychiatric and Substance
                          Abuse) Hospitals.
623100                   Nursing Care Facilities (Skilled Nursing
                          Facilities).
623200                   Residential Intellectual and Developmental
                          Disability, Mental Health, and Substance Abuse
                          Facilities.
623300                   Continuing Care Retirement Communities and
                          Assisted Living Facilities for the Elderly.
623900                   Other Residential Care Facilities.
624100                   Individual and Family Services.
624200                   Community Food and Housing, and Emergency and
                          Other Relief Services.
624300                   Vocational Rehabilitation Services.
624400                   Child Care Services.
711100                   Performing Arts Companies.
711300                   Promoters of Performing Arts, Sports, and
                          Similar Events.
711400                   Agents and Managers for Artists, Athletes,
                          Entertainers, and Other Public Figures.
711500                   Independent Artists, Writers, and Performers.
712100                   Museums, Historical Sites, and Similar
                          Institutions.
713200                   Gambling Industries.
721100                   Traveler Accommodation.
721300                   Rooming and Boarding Houses, Dormitories, and
                          Workers' Camps.
811200                   Electronic and Precision Equipment Repair and
                          Maintenance.
812100                   Personal Care Services.
813100                   Religious Organizations.
813200                   Grantmaking and Giving Services.
813300                   Social Advocacy Organizations.
813400                   Civic and Social Organizations.
813900                   Business, Professional, Labor, Political, and
                          Similar Organizations.
999200                   State Government.
999300                   Local Government.
------------------------------------------------------------------------

IX. Technological Feasibility

A. Introduction

    The Occupational Safety and Health Administration (OSHA) is 
proposing a Heat Injury and Illness Prevention standard that will 
require employers, whose employees are occupationally exposed to 
hazardous heat, to develop and implement a heat injury and illness 
prevention plan. As part of the plan, this proposed standard will 
require employers to implement control measures to mitigate the risk to 
workers from occupational exposure to heat when temperatures exceed 
specified triggers.
    As discussed in Section II., Pertinent Legal Authority, OSHA must 
prove, by substantial evidence in the rulemaking record, that its 
standards are technologically and economically feasible, which the 
Supreme Court has defined as ``capable of being done, executed, or 
effected'' (American Textile Mfrs. Inst. v. Donovan (Cotton Dust), 452 
U.S. 490, 508-09 (1981)). A standard is technologically feasible if the 
protective measures it requires already exist, can be brought into 
existence with available technology, or can be created with technology 
that can reasonably be expected to be developed

[[Page 71032]]

(United Steelworkers v. Marshall (Lead I), 647 F.2d 1189, 1272 (D.C. 
Cir, 1980), cert. denied, 453 U.S. 913 (1981); Am. Iron & Steel Inst. 
v. Occupational Safety & Health Admin. (Lead II), 939 F.2d 975, 980 
(D.C. Cir. 1991)). OSHA has reviewed the requirements that would be 
imposed by the proposed Heat Injury and Illness Prevention standard and 
assessed the technological feasibility of complying with its 
requirements. As a result of this review, OSHA has preliminarily 
determined that achieving compliance with the proposed standard is 
technologically feasible.

B. Methodology

    For this proposed standard, OSHA evaluated the provisions to 
identify which requirements proposed the implementation of engineering 
control measures or would address facility and equipment related 
aspects of heat illness prevention, as opposed to those that would 
establish programs, processes, or procedures. OSHA also reviewed the 
workplace control practices currently in place across the affected 
industries as well as the recommended practices of industry trade 
associations and standards-setting organizations.
    For this technological feasibility analysis, OSHA grouped 
establishments by indoor work settings based on the similarity of 
worker exposure sources (i.e., equipment or processes that generate 
heat versus ambient heat) and outdoor work settings, including mobile 
or transient sites, with exposure primarily to ambient heat and heat-
generating processes. These work settings, and examples of occupations 
found in these settings, are outlined in table IX-1 below.

 Table IX-1--Facility Types Analyzed in OSHA's Preliminary Technological
                          Feasibility Analysis
------------------------------------------------------------------------
                                                      Example facility
        Work setting               Heat source        types/occupations
------------------------------------------------------------------------
Indoors.....................  Heat Generating        Commercial
                               Processes.            Laundry and
                                                     Drycleaning
                                                     Commercial
                                                     Kitchens
                                                     Foundries
                                                    
                                                     Manufacturing
                                                     (Paper Mills, Wood
                                                     Processing,
                                                     Chemical
                                                     Processing)
                              Ambient Heat........   Maintenance
                                                     and Repair Service
                                                     Warehouses
                                                    ....................
                                                     Sales
                                                     Related Industries
Outdoors....................  Ambient Heat at        Airline
                               Fixed Locations.      Ground Workers
                                                     Building
                                                     Material and
                                                     Equipment Suppliers
                                                     Maintenance
                                                     and Repair Service
                                                     Recreation
                                                     and Amusement
                                                     Sales
                                                     Related Industries
                              Ambient Heat at       
                               Transient and         Agriculture,
                               Mobile Work Sites.    Forestry, and
                                                     Fishing
                                                    
                                                     Construction
                                                     Landscaping
                                                     and Facilities
                                                     Support
                                                     Logging/
                                                     Forestry
                                                     Oil and Gas
                                                     Extraction and
                                                     Support Service
                                                     Postal and
                                                     Delivery Services
                                                     Sanitation
                                                     and Waste Removal
                                                    
                                                     Transportation
                                                     (Land, Water, and
                                                     Rail), including
                                                     Scenic and
                                                     Sightseeing
                                                    
                                                     Telecommunications
                                                     and Utility Workers
                              Heat Generating        Asphalt
                               Processes.            Paving
                                                     Cement
                                                     Kilns
------------------------------------------------------------------------

C. Environmental Monitoring

    The proposed rule includes requirements for employers to monitor 
environmental conditions in order to determine whether certain controls 
to protect employees exposed to heat at or above the trigger level, 
expressed in terms of heat index or wet bulb globe temperature (WBGT), 
need to be implemented. The proposed rule also requires employers 
utilizing fans in indoor work areas or break areas to identify any such 
areas where the ambient temperature (AT) exceeds 102 [deg]F in order to 
evaluate whether fan use may be harmful. As part of OSHA's assessment 
of the technological feasibility of these proposed requirements, the 
agency must determine whether available methods exist for measuring 
heat index, WBGT, and AT. As explained below, all three metrics can be 
monitored via instruments currently on the market.
I. Heat Index
    Heat Index (HI) is meant to reflect the temperature that the body 
``feels,'' by combining ambient temperature and either dew point 
temperature, or more commonly relative humidity (RH) (Anderson et al., 
2013; NWS, 2024c; Steadman, 1979). The underlying formula for heat 
index is complex and uses several assumptions, including human body 
mass and height, clothing, amount of physical activity, individual heat 
tolerance, sunlight and ultraviolet radiation exposure, and wind speed. 
In the HI formula, the coefficients have been determined through 
empirical studies and mathematical modeling to approximate how humidity 
influences the effect of temperature. Different coefficients can vary 
depending on the unit of temperature and the formula might differ 
slightly between regions or meteorological agencies.
    While calculating HI involves a fairly complex equation, methods 
for determining the HI using the ambient temperature (AT) and RH are 
widely available and simple to use. The most accurate way to determine 
the HI at work sites is through the use of direct read monitoring 
devices. These types of devices are readily available on the market 
(ERG, 2024b). The handheld devices, commonly called heat-stress 
monitors or heat index monitors, measure the AT, RH, and dew point, and 
provide the HI. These devices provide real-time, on-site measurements 
and can be used both indoors and outdoors. Conversely employers could 
use psychrometers and thermometers to measure AT and RH, then calculate 
the HI using any of the tools described

[[Page 71033]]

below. Both psychrometers and thermometers are available in digital and 
analog versions. For outdoor work sites, employers could also use local 
forecast weather data to obtain the AT and RH. This information can 
then be used to estimate the HI for a particular location using 
available charts and calculators. However, because local forecast 
conditions may not reflect actual working conditions indoors, OSHA is 
not proposing to permit the use of forecast data to determine indoor 
HI.
    The National Weather Service (NWS) has two charts available on 
their website which employers can use to determine the HI, the Heat 
Index Chart and the Heat Index Chart for Low Humidity Locations.\135\ 
The Heat Index Charts can be used for environments with RH ranging from 
5% to 100%. To find the HI using the chart the employer must first 
determine the AT and RH. The HI is located in the cell where the two 
values meet on the chart. The National Weather Service (NWS) also has a 
calculator available on their website that allows users to calculate HI 
by entering in the temperature and humidity or dew point.\136\ However, 
this calculator notes that results using temperatures and RH outside of 
the range of the NWS heat index chart may not be accurate.
---------------------------------------------------------------------------

    \135\ The NWS charts contain risk categories that may not align 
with the proposed rule as OSHA is not relying on the risk categories 
noted in the chart.
    \136\ https://www.wpc.ncep.noaa.gov/html/heatindex.shtml.
---------------------------------------------------------------------------

    Another way employers can determine the HI is through the OSHA-
NIOSH Heat Safety Tool,\137\ which allows users to access HI data from 
a mobile phone. The Heat Safety Tool pulls hourly forecasts specific to 
the inputted outdoor location from the NWS to estimate the local heat 
index. This tool is available for both Android and Apple mobile devices 
and can be downloaded from the app stores, as well as the OSHA website. 
As previously mentioned, while the tool is useful for outdoor work 
environments, local weather data may not accurately reflect indoor 
working conditions or situations where heat is also generated as part 
of the work process.
---------------------------------------------------------------------------

    \137\ https://www.osha.gov/heat/heat-app.
---------------------------------------------------------------------------

    OSHA has preliminarily concluded that conducting exposure 
assessments to determine the HI is technologically feasible for most 
operations, most of the time.\138\ HI is simple, easy-to-understand, 
and easily accessible. For indoor workplaces employers will need to 
take on-site measurements to determine the HI. This can be done using 
either direct reading instruments currently on the market or by 
measuring AT and RH with psychrometers and thermometers and using 
charts or online calculators to calculate the HI. OSHA seeks additional 
information and comments on the feasibility of measuring HI in 
different environments, including indoor environments and where heat-
generating processes occur.
---------------------------------------------------------------------------

    \138\ OSHA notes that Oregon currently uses HI thresholds in its 
state standard, which is further evidence that the measurements are 
feasible. OR Admin. Code 437-002-0156 (indoor and outdoor) and 437-
004-1131 (agriculture).
---------------------------------------------------------------------------

II. Wet Bulb Globe Temperature (WBGT)
    WBGT is a measure of heat exposure that incorporates the impact of 
sunlight and wind, in addition to temperature and humidity. It was 
derived in the 1950s to track exposure and limit heat-related illness 
(HRI) among the U.S. Armed Services (Budd, 2008). WBGT is calculated as 
the weighted average of globe temperature, wet bulb temperature, and 
dry bulb temperature, and accounts for AT, RH, wind speed, and solar 
radiation. WBGTs are measured with specialized equipment currently 
available on the market.
    Indeed, both NIOSH REL's and ACGIH TLV's for heat stress are based 
on WBGT readings. Also, OSHA currently collects WBGT readings during 
inspections to evaluate the potential hazard from exposure to heat in 
accordance with procedures for performing workplace assessments in the 
OSHA Technical Manual (OTM), section III., chapter 4.
    A standard WBGT instrument has a 0.15-meter, or 6-inch, black globe 
to measure globe temperature and a wetted thermometer to measure the 
natural wet bulb temperature (Budd, 2008). Various WBGT monitors have 
been developed, many of which use a smaller black globe and/or a 
relative humidity sensor in place of a wetted thermometer. Relative 
humidity measurements are used to calculate wet bulb temperature based 
on psychometric principles. Some well-known WBGT monitors include the 
QUESTemp series by TSI and smaller handheld devices such as that made 
by Kestrel (ERG, 2024b).
    Although several accurate WBGT monitoring devices are available, 
OSHA notes that some lower-cost devices may not be sufficient to 
accurately measure employees' heat exposure. Non-standard monitors can 
be found for a lower cost, but they may not fully align with 
traditional WBGT thermometer measurements. Some devices may be designed 
to be more conservative in their measurements than others. In a review 
of WBGT, Budd (2008) identified key limitations of this standard 
equipment to measure WBGT. Four of the main concerns were inconsistent 
equilibration times, insufficiently robust calibration procedures, and 
the use of non-standard globe thermometers and natural wet bulb 
thermometers. Smaller bulbs typically result in shorter equilibration 
times, which make readings more sensitive to short-term changes in 
environmental conditions than larger bulbs. However, few peer-reviewed 
studies have been published evaluating these potential sources of error 
and OSHA anticipates technology has likely improved since Budd's 
evaluation in 2008. Given these technical considerations--including 
equilibration times and the need for robust calibration procedures--the 
use of WBGT on-site will require training to properly operate. The 
extent of the training would vary depending on the type of monitor.
    OSHA has preliminarily determined that instruments to accurately 
monitor WBGT are commercially available. OSHA seeks additional comments 
on the use of WBGT and to identify situations in which WBGT would or 
would not be practical or pose challenges for employers to measure.
III. Ambient Temperature (AT)
    AT is the air temperature measured using a thermometer. The primary 
types of thermometers used for measuring AT are liquid-in-glass 
thermometers, electrical thermocouples, and resistance thermometers 
(thermistors). Each of these types of thermometers are commercially 
available in a wide variety of designs. The States with permanent 
outdoor occupational heat standards, California and Washington, 
currently use fixed value thresholds of AT, further indicating the 
feasibility of this metric (California Occupational Safety & Health 
Administration, 8 CCR 3395; Washington Division of Occupational Safety 
and Health, WA Admin. Code 296-62-095). Based on the widespread public 
availability of thermometers to measure AT, OSHA has preliminarily 
determined that it is technologically feasible for employers to assess 
AT in their workplace.
IV. Preliminary Findings on Environmental Monitoring
    Several different types of instruments and methods to determine the 
Heat Index and WBGT are commercially available. These include the 
Kestrel and QuesTemp currently used by OSHA, in addition to various 
mobile device applications supported by NWS and NIOSH. At outdoor work 
sites, employers have the option of tracking local heat index forecasts 
provided by the NWS or other reputable sources in

[[Page 71034]]

lieu of measuring for Heat Index or WBGT. In addition, thermometers to 
measure AT are widely available. Because the technology necessary to 
comply with the proposed standard currently exists and is commercially 
available, OSHA preliminarily concludes that the proposed standard's 
monitoring requirements are technologically feasible.

D. Engineering Controls

    Engineering controls are measures that reduce, isolate, or remove a 
hazard from the workplace. These engineering controls can be used to 
reduce exposure to heat without relying on changes in employee 
behavior. Therefore, engineering controls are often the most effective 
type of control to address workplace hazards and can also be a cost-
effective layer of protection. The following are some examples of 
engineering controls that may reduce heat stress:
     Use air-conditioning,
     Increase general ventilation,
     Provide cooling fans,\139\
---------------------------------------------------------------------------

    \139\ It should be noted that under certain conditions the use 
of fans may contribute to heat strain (Morris, 2021). See further 
discussion in the Explanation of Proposed Requirements for paragraph 
(e)(6), Evaluation of fan use.
---------------------------------------------------------------------------

     Run local exhaust ventilation where heat is produced 
(e.g., laundry vents),
     Use reflective shields to block radiant heat,
     Insulate hot surfaces (e.g., furnace walls),
     Stop leaking steam,
     Provide shade for outdoor work sites.
    Under the proposed standard, when exposures to heat exceed 
specified triggers, employers must implement feasible controls to 
reduce employee's exposures to heat. The requirements for the use of 
engineering controls differ based on the location of work, whether 
indoors or outdoors. For indoor work sites, employers are required to 
provide a break area and ensure that work areas exceeding the trigger 
are equipped with air-conditioning, fans and ventilation, or in the 
case of radiant heat, other controls to reduce heat exposure. For 
outdoor work sites, employers are required to provide a break area with 
either shade or air-conditioning.
I. Workers Exposed to Heat Generating Process
    As shown in Table IX-1--Facility Types Analyzed in OSHA's 
Preliminary Technological Feasibility Analysis, employees in both 
indoor and outdoor work operations can be exposed to heat from work 
processes. Radiant heat can be generated by equipment and processes 
such as, but not limited to, cement kilns, asphalt paving equipment, 
commercial laundry machines, ovens in kitchen and bakery operations, 
foundries and other furnaces, and steam pipes. Under the proposed rule, 
OSHA is requiring employers to cool each indoor work area using either 
controls that increase evaporative heat loss from the worker (such as 
air-conditioning or fans) or through controls that remove the worker's 
exposure to radiant heat in the workspace. Because OSHA anticipates 
that the use of fans, dehumidifiers, and air-conditioning to control 
exposures from heat generating processes will be implemented in a 
similar manner to those controlling for ambient temperature exposures, 
the discussion on feasibility of those controls is contained in Section 
IX.D.II.A, Indoor Workspaces. OSHA requests comments on the 
appropriateness of this determination and seeks information on 
situations where the use of fans and air-conditioning would differ.
    The engineering approaches to controlling radiant heat gain to the 
worker can be divided into two categories, those that reduce the amount 
of radiant heat in the workspace or those that shield the worker from 
the radiant heat source itself. Researchers suggest the following 
actions for reducing radiant heat exposures: interpose line-of-sight 
barriers; insulation, reflective shield and/or metallic reflecting 
screen, heat reflective clothing; mechanical ventilation (fans, 
blowers, chillers, etc.), air-conditioning where possible, and locating 
hot process away from work areas (NIOSH, 2016; Chesson, 2012).
    Reducing radiant heat in the workspaces typically requires at least 
one of the following actions: lowering the process temperature, which 
may not be compatible with the temperature requirement of the 
manufacturing processes; relocating or isolating the heat source; 
insulating or cooling the heat source; or changing the emissivity of 
the hot surface by coating the material. Engineering controls for 
shielding the work from the radiant heat requires placing line-of-sight 
radiant reflective barriers or shielding between the heat source and 
the worker.
    Of these control methods, radiant reflective shielding is generally 
the easiest to install. NIOSH notes that radiant reflective shielding 
can reduce the radiant heat load by as much as 80% to 85% (NIOSH, 
2016). Employers who choose to install shielding will need to consider 
work process flows so that placement does not interfere with the work. 
Remotely operated tongs, metal chain screens, or air or hydraulically 
activated doors that are opened only as needed are some of the 
possibilities.
    Isolating the source could involve construction of walls or other 
containment around hot equipment or process such as erecting barriers 
around a kiln that control heat transfer to nearby work areas (NIOSH, 
2016). Morris et al. noted that ``investigations into reducing the 
solar (radiative) heat load on workers is promising, revealing that 
work capacity can be more than doubled with the removal of an external 
radiative load,'' and further explained that radiation screens can be 
used within manufacturing shops to shield workers from heat originating 
from hot machinery (Morris et al., 2020). Another example of isolating 
the source would be installing insulation around pipes and similar 
equipment in the workplace that emits heat. Similarly, because leaks 
from steam valves and steam lines in manufacturing processes can 
contribute to heat stress by increasing water vapor in the air, 
eliminating these sources of water vapor can help reduce the overall 
vapor pressure in the air and thereby increase evaporative heat loss by 
facilitating the rate of evaporation of sweat from the skin (NIOSH, 
2016). OSHA requests comments and data on other methods employers have 
utilized to isolate radiant heat from heat-generating processes.
    Examples of waste heat recovery technology include recovery of heat 
from steam through condensation that would otherwise be released into 
the workspace. Heat recovery systems improve energy efficiency by 
utilizing heat transfer from hot liquids or gases and recover heat that 
would otherwise go to waste. Some commercial building ventilation 
systems use heat exchangers to transfer heat from exhaust air to the 
fresh intake air (NIOSH, 2016).
    With regards to modifying the process or operation, OSHA notes that 
lowering the process temperature may not be compatible with process 
requirements. However, there might be ways of using materials with 
lower melting points or chemicals with faster curing times thereby 
reducing overall radiant heat production. This might also include 
modifying the process and work practices by limiting the time required 
to complete certain tasks or automating certain tasks, such as 
collecting samples.

[[Page 71035]]



              Table IX-2--Heat Generating Process Controls
------------------------------------------------------------------------
             Controls                             Examples
------------------------------------------------------------------------
Local exhaust ventilation (LEV) at   LEV designed and installed
 heat-generating sources.            at points of high heat or moisture
                                     production (such as exhaust hoods
                                     in laundry rooms or steam presses,
                                     commercial kitchen exhaust hoods).
                                     Similar to LEV used to
                                     capture air contaminants. Dampeners
                                     and hood vary depending on moisture
                                     level of air.
Installation of waste heat           Used with LEV to convert
 recovery technology.                heat to energy that is fed back
                                     into the system.
                                       [cir] Regenerative and
                                        recuperative burners: Capture
                                        and use the waste heat from the
                                        hot flue gas from the combustion
                                        process.
                                       [cir] Tube heat exchangers:
                                        Recover low to medium waste heat
                                        are mainly used for heating
                                        liquids.
Isolating the source of radiant      Process enclosures around
 heat.                               heat producing components.
                                     Containment of heat
                                     producing equipment in rooms
                                     without workers.
Shielding or barriers that are       Shielding to stop radiant
 radiant-reflecting or heat-         heat from reaching workstations.
 absorbing.
                                       [cir] Reflective Shield:
                                        Stainless steel, aluminum or
                                        other bright metal surfaces
                                        reflect heat back towards the
                                        source.
                                       [cir] Absorbent shields: Water-
                                        cooled jackets made of black-
                                        surfaced aluminum absorb and
                                        carry away heat.
Thermal insulation on hot surfaces   Reducing the radiant heat
 (e.g., steam pipes).                emission from hot surfaces.
                                       [cir] Covering hot surfaces with
                                        sheets of low emissivity
                                        material or paint that reduces
                                        the amount of heat radiated from
                                        this hot surface into the
                                        workplace.
                                     Insulating Hot Surfaces.
                                       [cir] Insulation reduces the heat
                                        exchange between the source of
                                        heat and the work environment.
Increasing the distance between      Moving the workstation
 workers and the heat source.        further away from the heat source.
                                     Repositioning controls a
                                     cooler location.
------------------------------------------------------------------------

A. Preliminary Feasibility Finding for Heat Generating Processes.
    The proposed rule does not specify which of the engineering 
controls must be used for indoor workplaces. It only requires that 
employers implement other measures that reduce employee exposure to 
radiant heat in the work area as an alternative option to the use of 
fans or air-conditioning. OSHA has preliminarily determined that there 
are a number of technologically feasible engineering controls available 
to employers. Employers are free to choose any combination that 
effectively reduces exposures. Based on the discussion above, OSHA has 
preliminarily determined that there are no technological hurdles to 
compliance with this requirement for indoor workplaces.
    OSHA acknowledges the limited information available on working 
outdoors near heat generating processes. OSHA seeks information and 
data on whether and under what circumstances the control options used 
to reduce exposure to radiant heat in indoor work areas might also be 
feasible for outdoor work settings.
II. Workers Exposed to Ambient Heat
A. Indoor Workplaces
    Employees in indoor workplaces, such as maintenance facilities, and 
warehousing, can be exposed to HRIs when ambient temperatures increase. 
See Table IX-1--Facility Types Analyzed in OSHA's Preliminary 
Technological Feasibility Analysis. Due to factors such as building 
materials, insulation, and reduced air movement, the air temperatures 
in indoor workplaces without air-conditioning can in some cases exceed 
the temperature outdoors. The proposed rule would require that 
employers reduce these exposures by utilizing controls to cool the work 
area and provide a break area that is air-conditioned or has an 
alternate means of providing air movement and, if appropriate, humidity 
control to promote evaporative and convective cooling.
    In response to the advance notice of proposed rulemaking (ANPRM) 
and previous Requests for Information (RFI), OSHA received numerous 
comments on the use of engineering controls for preventing heat-related 
injury and illness in both indoor and outdoor work settings. The most 
mentioned engineering controls were the provision of air-conditioning, 
fans, swamp coolers (i.e., evaporative coolers), portable air-
conditioners, access to air-conditioned zones, air-conditioned tents/
trailers and shaded areas. (e.g., Document ID 0094; 0206; 0278, Att. 1; 
0392; 0448, Att. 1; 0523, Att. 1; 0551; 0562; 0588; 0610, Att. 1; 0637, 
Att. 1: 0679, Att. 1). Some commenters mentioned specific types of 
devices that could be used, such as portable air-conditioning units and 
evaporative coolers. (e.g., Document ID 0445; 0595, Att. 1; 0612, Att. 
1). For preventing humid working conditions, commenters suggested the 
use of dehumidifiers. (Document ID 0661, Att. 1). OSHA discusses of the 
feasibility of these controls below.
    Some commenters suggested other controls, such as architectural 
controls like altering roofs to reflect solar radiation using 
reflective materials, green roofs, rooftop sprinklers, or painting 
roofs white. Also suggested was the use of light-colored building 
material, green infrastructure, pervious pavements, external awnings, 
and window coverings to aid in mitigating indoor heat. While OSHA 
understands that the use of these controls may assist an employer in 
reducing ambient heat exposures in the workplace, this analysis focuses 
on the engineering controls outlined specifically in the regulatory 
text of the proposed rule. OSHA notes, however, that the proposed 
standard does not prohibit the use of other controls in addition those 
specified in the standard.
I. Air-Conditioning
    Air-conditioning is one of the options to control heat in the 
workplace and is the most effective way to reduce heat strain because 
it reduces the heat exposure directly (Day et al., 2019; Jay et al., 
2019; Morris et al., 2020; Morrissey et al., 2021b). Air-conditioning 
technology is widely

[[Page 71036]]

available and currently in use in many workplaces. However, OSHA 
understands that the use of air-conditioning to address heat hazards 
may not be practical in all occupational settings, such as outdoors or 
in large factories, and alternative control strategies need to be 
implemented (Foster et al., 2020; Mekjavic et al., n.d.; Morris et al., 
2020).
    HEAT-SHIELD, a research program funded by the European Union, 
evaluated strategies for the reduction of heat illness in the 
manufacturing industry (Mekjavic et al., n.d.). Researchers from the 
Heat Shield project successfully implemented several heat stress 
mitigating strategies within a manufacturing plant producing automobile 
rear lights. To aid in enhanced evaporative heat loss by the workers, 
the production hall was fitted with a system of ducts to increase the 
cooling air flow to the production hall and local workstations. The 
ducts were installed so that the air flow in the plant could be 
individually adjusted at the local workstations; alternatively, 
individual workers could also use an electrical fan in proximity to 
their workstation to increase the air flow (Mekjavic et al., n.d.). The 
study does not indicate what method of cooling was used to cool the air 
provided (conditioned, evaporative cooling, etc.). However, OSHA 
believes that similar designs could be implemented in manufacturing 
facilities using conditioned air.
    In response to the ANPRM, some commenters stated that temperature 
controls or air-conditioning systems are not feasible in many 
industrial settings and in large industrial plants that include tens of 
thousands of square feet of floor space, specifically foundries, forge 
shops, and other workplaces with hot work processes (e.g., Document ID 
0277). Bakeries and dairy product manufacturers were specifically 
mentioned as having unique circumstances because of the need to offset 
carbon monoxide and heat emitted during the baking or production 
process for employee safety, and due to food safety concerns (Document 
ID 0699, Att. 1). Another commenter added that environmental 
temperature controls may not be feasible in some areas that are 
designed to be open or partially open to the outside. Installing air-
conditioning in all work areas would not be physically possible and 
could be cost prohibitive (Document ID 0657, Att. 1; 0684, Att. 1; 710, 
Att. 1; 0724, Att. 1). This sentiment was also echoed in available 
literature. Mekjavic et al. noted that due to design elements of some 
manufacturing facilities, such as minimal insulation, the economic 
burden renders the installation of facility wide air-conditioning as 
not possible (Mekjavic et al., n.d.). OSHA understands this concern and 
is therefore not requiring all employers to install air-conditioning 
throughout their facility.
    However, OSHA recognizes that air-conditioning can be installed in 
some indoor locations and is effective at reducing the exposure to 
ambient heat in the workplace. A feasibility study presented at the 
10th International Livestock Environment Symposium compared the costs 
and benefits of air-conditioning to an evaporative cooling system in a 
large dairy barn (measuring 43.3m by 25.6m) (Li et al., 2018). The 
researchers simulated summer conditions in barns across Tampa, FL; 
Sacramento, CA; Syracuse, NY; and Madison, WI. They determined that 
air-conditioning was capable of maintaining maximum indoor temperatures 
of 23 [deg]C to 27.4 [deg]C (74.3 [deg]F to 81.3 [deg]F) (Li et al., 
2018).
    Another study conducted by Morrissey et al. (2021b) provided a flow 
chart for selecting appropriate heat controls and included air-
conditioning as a recommended option for all work sites with access to 
power. Anderson and Souza (2017) specifically identify air-conditioning 
(i.e., bulk air cooling, spot air coolers, and air-conditioned cabins) 
as a heat management strategy for underground mines. In addition, 
several commenters on the ANPRM noted that some indoor facilities do 
provide areas for employees to take breaks in temperature-controlled 
environments, indicating that an air-conditioned break area is capable 
of being installed for cooling in indoor work environments (Document ID 
0612, p. 2; 0680, p. 10; 0691, pp. 10-11; 0777, Att. 2, p. 33; 1071, p. 
2; 1072, pp. 1, 4).
    Despite common statements of its efficacy in review articles and 
studies, air-conditioning as a control to reduce heat exposure at the 
workplace is not commonly evaluated in the occupational setting. It is 
unclear if the very definition of air-conditioning (an approach that 
directly removes heat) or feasibility limitations might explain the 
limited nature of this body of literature. Therefore, OSHA is seeking 
information regarding the current use of air-conditioning in the 
industries covered under the scope of the rulemaking.
II. Humidity Control
    For indoor work sites, OSHA is proposing to require employers who 
do not provide air-conditioned break areas or workspaces to implement 
humidity control (when appropriate) in conjunction with some form of 
air movement in those spaces. An article by D. Jeff Burton, P.E. CIH, 
published in the Occupational Health and Safety magazine reviewed the 
use of dehumidification to maintain acceptable indoor air quality in 
occupational settings (Burton, 2006). In addition to dehumidification 
approaches utilizing existing HVAC systems, the article noted that 
stand-alone dehumidifiers are commercially available and can be used 
where HVAC systems do not effectively control humidity (Burton, 2006). 
Indeed, OSHA expects that in most cases employers will use one of the 
many stand-alone dehumidifier models on the market to achieve the 
humidity control required by the proposed standard. In addition, in 
facilities with processes that produce moisture, exhaust systems can 
often be used to remove moist air and eliminate humidity gain.
III. Fans
    Another engineering control identified by OSHA is the use of fans 
to help circulate air. Fans do not necessarily lower temperature but 
can make it easier for the body to dissipate heat. Depending on the 
work setting, fans can be used before work, during work, or during rest 
breaks. Information contained in the rulemaking docket indicates fans 
can be easily implemented in a variety of work environments. Large 
ceiling fans can be installed to increase air movement. In certain 
facilities, pedestal fans can be used to provide air movement at 
workstations. Some commenters mentioned that they use fans for air 
circulation in indoor facilities (e.g., Document ID 0277, 0283). During 
the SBREFA hearings, one SER reported that they open the doors in the 
mornings and use large ceiling fans to draw cooler air into the 
building, and then shut the doors in the afternoons to reduce the 
infiltration of hot outside air into the building. (Document ID 1081, 
p. 29).
    Several studies evaluated by OSHA indicate that fan usage in 
industrial settings is prevalent. A recent J.J. Keller Center for 
Market Insights Pulse Poll indicates that 65% of employers provide 
fans, ventilation, or reflective shields to help control exposures to 
heat stress (JJ Keller, 2022).
    As mentioned above, HEAT-SHIELD evaluated strategies for the 
reduction of heat illness in the manufacturing industry (Mekjavic et 
al., n.d.). To aid in enhanced evaporative heat loss by the workers, 
the production hall was fitted with a system of ducts to increase the 
cooling air flow to the production hall

[[Page 71037]]

and local workstations. In addition, some workers utilized electrical 
fans in proximity to their individual workstations to increase the air 
flow (Mekjavic et al., n.d.).
    A 2021 study by Morris et al. determined that facilitated 
ventilation, through the use of electric fans, supports convective and/
or evaporative heat loss and lowers occupational heat strain at a 
considerably lower operation and production cost compared to air-
conditioning. The authors noted that fans were also easier to 
personalize cooling by directing air flow towards specific workers, 
rather than cooling an entire area; they could be transported to remote 
workspaces and could be used both during work and at specific cooling 
areas where workers take intermittent cooling breaks (Morris et al., 
2021).
    Fans have even been incorporated into chairs as demonstrated by 
Watanabe et al. (2009). In this study, researchers evaluated thermal 
comfort using chairs with attached fans under various climactic 
conditions, while participants performed light office tasks such as 
word processing. One control chair and two ``fan chair'' designs were 
assessed; each ``fan chair'' had a fan under the seat and behind the 
backrest and received a positive response from the worker. Morris et 
al. (2020) also noted the relevance of chair fans, stating that 
``miniature electrical fans could be incorporated into chairs, for 
seated workers, to deliver effective cooling while minimizing 
disturbances to the work environment'' (Morris et al., 2020).
    There is an additional body of research investigating fans as a 
heat control in large dairy barns due to the sensitivity of cow 
productivity to heat stress. Although not directly applicable to HRI 
reduction in humans, as with air-conditioning described above, this 
research provides insight into the extent to which industrial fans can 
be installed in large barn or warehouse-like structures (Calegari et 
al., 2012; Correa-Calderon et al., 2004; Davidson et al., 2021; 
Drwencke et al., 2020; Ortiz et al., 2010; Shiao et al., 2011; Urdaz et 
al., 2006).
    Evidence of the existing use of fans in occupational settings can 
be seen in existing State requirements and in some collective 
bargaining agreements. For example, Minnesota's standard governing 
indoor ventilation and temperature includes a provision for providing 
indoor ventilation and acceptable temperature ranges in places of 
employment to prevent employee exposure to indoor environmental heat 
conditions (MN Admin. Code 5205.0110). In addition, comments from the 
Teamsters in response to the ANPRM included examples of collective 
bargaining agreements that demonstrate steps employers have taken to 
address occupational HRIs (Document ID 0707, pp. 14-17). Items included 
provisions for work area ventilation when the plant is hot and the 
installation of fans to reduce excess heat or humidity in work rooms. 
Employers covered under these agreements may already be in compliance 
with some of the requirements of the proposal.
    Although fan use can be effective at reducing heat stress, fans may 
introduce additional hazards in some workplaces due to the increase in 
air movement. In indoor settings where air contamination is a concern, 
the use of fans may interfere with existing ventilation and increase 
worker exposure to hazards. OSHA acknowledges that in some cases, the 
work site may need to be evaluated to ensure that the use of fans does 
not interfere with existing ventilation designed for the control of 
dust and other air contaminants. OSHA seeks comments on work settings 
where the use of fans is not feasible due to contamination concerns and 
requests additional information on what controls, including the use of 
air-conditioning, employers use to prevent heat-related illnesses in 
these settings.
    In addition, research has shown that under certain conditions 
(e.g., high temperatures), fan use can increase the hazard of heat 
strain. See Section V.C., Risk Reduction for a more detailed discussion 
of fan use alone during elevated temperature events. OSHA requests 
comments on indoor work settings that may experience temperatures above 
102[deg]F and seeks information on what controls employers implement 
when fan use is contraindicated or when temperatures exceed 102 [deg]F.
IV. Evaporative Coolers
    Another engineering control, evaporative coolers, work by using a 
fan to pass air over a pad or ceramic surface saturated with water. The 
evaporation of the water reduces the air temperature. In warm dry 
climates, evaporative coolers can be used to lower air temperatures as 
much as 20 [deg]F (USGS). They consume much less energy than air-
conditioning and can be used in buildings with openings to the outside. 
However, because evaporative coolers cool through increasing air 
humidity, they are not as effective at relative humidity above 60%.
    A NIOSH Health Hazard Evaluation (HHE) conducted in September 2006 
demonstrates the feasibility of evaporative cooler use in indoor 
workspaces. The evaluation was conducted at a glass manufacturing 
facility in Indiana. In the hot end of the glass-making process, raw 
materials (recycled glass, sand, soda ash, and limestone) were melted 
together in a gas furnace at temperatures of 2,300 [deg]F to 2,800 
[deg]F (Dowell & Tapp, 2007). The company used various controls in the 
hot end of the plant during the hot summer months to reduce the risk of 
heat-related illness. The controls included fans which supplied cooler 
air from the basement of the facility (man coolers), and evaporative 
cooling fans (swamp coolers) (Dowell & Tapp, 2007).
    Furthermore, portable evaporative coolers are also commercially 
available for use expanding the ability for implementation in various 
work settings. These coolers can lower air temperatures by up to 18 
[deg]C (33 [deg]F) and cover up to 6,500 sq ft area, requiring only a 
power outlet and water supply.
V. Preliminary Feasibility Finding for Indoor Workplaces
    OSHA has determined that requirements for the use of engineering 
controls indoors under the proposed standard are technologically 
feasible for most operations, most of the time. For break areas, the 
proposed rule allows employers to utilize available air-conditioning 
systems or a combination of air movement and humidity control to 
promote evaporative cooling. The latter can be achieved with widely 
available fans and humidity control devices. For indoor work areas, 
OSHA has provided the employer with multiple control options for 
compliance with the proposed rule, allowing them to tailor the controls 
to the individual workplaces. Information obtained through the SBREFA 
process, comments, and research into existing control use indicate that 
many employers are already utilizing some combination of the required 
control options. OSHA seeks additional comments on its assumptions and 
other control options for these workers. Based on the discussion above, 
OSHA has determined that there are no technological hurdles to 
compliance with this requirement in the proposed rule.
B. Outdoor Workplaces
    For outdoor workplaces, the primary sources of exposure to heat 
hazards are ambient heat and direct sunlight. Under the proposed rule, 
OSHA is requiring employers to provide a break area with shade or air-
conditioning.
I. Shade
    As discussed in Section V., Risk Assessment, access to shade can 
reduce

[[Page 71038]]

the risk of HRI by decreasing exposure to solar radiation and, in turn, 
reducing overall heat load. Research has found that total heat exchange 
is greater in shaded conditions than sunny conditions (Otani et al., 
2021), indicating that access to shaded areas may reduce HRI. For 
outdoor workers exposed to direct sunlight, a commonly used engineering 
control is the use of a shelter or canopy to provide a shaded area for 
rest breaks. A wide variety of portable pop-up canopies are 
commercially available that can be easily set up and moved around for 
mobile work sites. Note that the proposed rule would not allow mobile 
equipment or machinery to be used to provide shade for rest breaks due 
to the potential safety hazards from unintended or accidental start up 
and movement of the equipment and the potential for equipment to 
release radiant heat.
    Working or resting in the shade can reduce the risk of HRI by 
decreasing exposure to solar radiation and reducing overall heat load. 
This control is applicable to all outdoor industries and is a key 
component of OSHA's ``Water. Rest. Shade.'' Heat Campaign guidance. The 
feasibility of providing shade for rest periods is demonstrated by OSHA 
enforcement data. During inspections conducted under the 2023 Heat 
National Emphasis Program, OSHA Compliance Officers completed a 
questionnaire regarding work site conditions. Over 1,300 responses were 
received indicating that 96% of employers inspected provided access to 
cool shaded areas (OSHA, 2023b). Several States, including California, 
Oregon, Colorado and Washington, have also incorporated requirements to 
provide shade into their heat-specific standards.\140\ While the scope 
of coverage varies by State, these standards require employers to 
provide workers with shade structures for rest breaks to recover from 
the heat. In addition, Maryland and Nevada proposed rules that would 
also require employers to provide access to shade.\141\
---------------------------------------------------------------------------

    \140\ (CA 8 CCR 3395; OR Admin. Code 437-002-0156 and 437-004-
1131; CO 7 CCR 1103-15:3; and WA Admin. Code 296-62-09535).
    \141\ Maryland COMAR 09.12.32; and Nevada Proposed Regulation 
LCB File No. R053-20.
---------------------------------------------------------------------------

    The addition of shaded break areas has been demonstrated as an 
integral part of a heat health plan to improve worker performance in 
the agricultural sector (Bodin et al., 2016; Morris et al., 2020; 
Glaser et al., 2022). Bodin et al. (2016) implemented a water, rest, 
and shade campaign with 56 Salvadoran sugarcane workers two months into 
the harvest season. Workers were provided a canopy for shaded breaks, 
insulated water bladders, and fixed break times. A qualitative study of 
the intervention reported consistent use of the shaded canopies and 
high worker satisfaction. A similar study of sugar cane workers 
conducted in 2022 indicated that workers were provided with break 
periods under adequate natural shade or tents that were designed to be 
moved easily to accompany the mobile workforce throughout each day. 
Tents were constructed from a netted fabric, open on two sides to 
provide adequate ventilation, and provided with stools for seated, 
shaded rest (Glaser et al., 2022).
    OSHA acknowledges that providing stationary shading outdoors may be 
difficult in some settings, particularly where work crews are highly 
mobile, such as in agricultural work. Even so, several studies indicate 
the widespread use of shade among agricultural workers. Fleischer et 
al. (2013) conducted a cross-sectional survey on HRI symptoms and 
working conditions in Georgia in 2011. Of the 405 farmworkers who 
completed the survey, 27% reported not having access to shade, 
indicating that some form of shade is available in the majority of 
these work environments. A study by Bethel et al. (2017) comparing 
conditions for outdoor agricultural workers in Oregon and Washington 
found that workers in Oregon more frequently reported the presence of 
shade structures \142\ and workers in Washington more often reported 
access to shade from trees.\143\ In Oregon, workers more frequently 
reported using shade structures and cars with air-conditioning compared 
with workers in Washington.\144\ However, the study was subject to 
several limitations. First, different methods of data collection were 
used in Oregon and Washington, which could have led to information 
bias. Participants in Washington completed a self-administered survey 
on touchscreen tablets at the work site, whereas participants in Oregon 
completed a personal interview administered by research staff at the 
housing facility. Second, participants were recruited differently in 
the two States, via outreach workers in Oregon and via employers and 
supervisors in Washington. Next, the conditions in which participants 
in the two States worked were vastly different. Specifically, 
participants in Washington primarily picked tree fruit in orchard 
settings, which provided a natural form of shade, whereas participants 
in Oregon primarily harvested blueberries with little shade (Bethel et 
al., 2017).
---------------------------------------------------------------------------

    \142\ 29% use in Oregon vs. 5% in Washington.
    \143\ 92% in Washington vs. 47% in Oregon.
    \144\ In Oregon, 26% of workers reported using shade structures 
and 14% used cars with air conditioning, compared to 3% and 6% 
(respectively) in Washington.
---------------------------------------------------------------------------

    The Fair Food Program is a partnership between growers and 
agriculture workers that includes safety and health standards which 
require participating employers to provide shade, water, bathrooms, and 
rest breaks. According to their 2021 report, 100% of Participating 
Growers have purchased and distributed shade structures to their crews, 
and they have observed steady increases in the quality of shade units 
at many growers' operations, including custom designs built to 
withstand field conditions. (Fair Foods Standards Council, 2021)
    During the SBREFA hearings, some SERs with outdoor settings 
reported using engineering controls such as natural shade (e.g., trees 
and dense vegetation), pop-up canopies, umbrellas, and portable shades. 
Some SERs with outdoor settings said they believed some engineering 
controls including shade and fans were infeasible for their workplace. 
(Document ID 1081, p. 30).
II. Air-Conditioning for Outdoor Workers
    Access to air-conditioning for outdoor work settings is primarily 
provided through the use of vehicles, trailers, and near-by buildings. 
OSHA understands that the use of air-conditioning has limited 
applications for outdoor workplaces. However, evidence in the docket 
indicates that it is feasible for a variety of outdoor situations.
    A 2018 study by Methner and Eisenberg evaluated the risk of HRI for 
employees engaged in strenuous work in an extremely hot outdoor 
environment, a park during summer months. Worker tasks included 
landscaping, demolition, and bricklaying. Park policy included the use 
of motor vehicles with air-conditioning as a cool-down area for breaks 
in remote locations where access to cooled buildings was limited 
(Methner and Eisenberg, 2018). As mentioned above Bethel et al. (2017) 
found that some workers in Oregon and Washington have access to cars 
with air-conditioning (14% vs. 3%).
    The use of portable air-conditioning units and vehicles with air-
conditioning for cooling is also supported by multiple ANPRM 
commentors. In response to OSHA's request for information on control 
options for outdoor work, the City of Phoenix commented that portable 
air-conditioning units are available and have received positive

[[Page 71039]]

responses from employees. The International Brotherhood of Electrical 
Workers (IBEW), AFL-CIO also indicated that employees in the utilities 
industry use a wide variety of cooling methods including air-
conditioning in trucks or trailers.
    During the SBREFA hearings, many SERs with outdoor work settings 
reported having air-conditioned vehicles or trailers on site that 
workers can use to cool down. When SERs were polled at two sessions, 
September 12th and 13th, on the types of engineering controls that are 
used ``to mitigate the impact of heat exposure to employees that work 
outdoors,'' two-thirds (66.7%) of the 30 responders reported using an 
``air-conditioned space.'' (Document ID 1081, p. 30).
    OSHA requests comments on additional ways employers have utilized 
air-conditioning for outdoor workers and obstacles encountered, if any.
III. Preliminary Feasibility Finding for Outdoor Workplaces
    OSHA has preliminarily determined that requirements for the use of 
engineering controls for outdoor break areas under the proposed 
standard are technologically feasible for most operations, most of the 
time. Information obtained through the SBREFA process, comments, and 
research into existing control use indicate that many employers are 
already utilizing some form of shade or air-conditioned space for 
employee cooling. For those remaining employers, OSHA anticipates they 
can quickly come into compliance through the implementation of shade or 
air-conditioned vehicles, trailers and other spaces, as described 
above. OSHA seeks additional comments on its assumptions and other 
control options for these workers. Based on the discussion above, OSHA 
has determined that there are no technological hurdles to compliance 
with this requirement.
C. Mobile Workplaces
    Options for the use of engineering controls for mobile work sites 
where the work is not performed at a fixed location are similar to 
other outdoor work sites. Portable canopies can be used to provide a 
shaded area for breaks. Where electricity is available, trailers with 
air-conditioning can be used as cool-down areas for rest breaks. Air-
conditioned vehicle cabs can also be used.
    OSHA found several examples in which employers agreed to provide 
shade for outdoor workers as part of contract negotiations around 
working conditions. As previously mentioned, the Teamsters submitted 
comments on the ANPRM that included examples of language from 
collective bargaining agreements demonstrating steps employers have 
taken to address occupational HRIs. Language included requirements for 
construction drivers, employees suffering from heat illness believing a 
preventative recovery period is needed or feeling the need to protect 
themselves from overheating, are required to be provided access to an 
area with shade that is either open to the air or provided with 
ventilation for a period of no less than five minutes (Document ID 
0707, p. 16).
I. Preliminary Feasibility Finding for Mobile Workplaces
    OSHA has preliminarily determined that there are no technological 
hurdles for the implementation of controls for workers with mobile work 
sites. Based on the discussion above, OSHA has preliminarily determined 
that it is technologically feasible, using commercially available 
products and technology, for employers with mobile work sites to 
provide workers with shaded or air-conditioned break areas. OSHA seeks 
comment on this determination and additional data and information on 
other feasible control options available for these mobile work sites.

E. Preliminary Feasibility Findings

    OSHA has reviewed the requirements that would be imposed by the 
proposed standard and has determined that achieving compliance with the 
proposed standard is technologically feasible most of the time, in most 
of the establishments and operations covered by the standard. As 
discussed above, the proposed rule is largely programmatic and offers 
the employer several control options. Under the proposed rule, 
employers can determine the controls best suited for their unique work 
environment in order to comply with the requirements for controls at 
break areas and work areas. Not all practices, procedures, or controls 
identified in this technological feasibility analysis will be necessary 
at all establishments: the proposed standard provides flexibility for 
employers to tailor their procedures, practices, and controls to the 
needs of their facility based on an assessment specific to that 
facility. Moreover, readily available and currently used technology is 
capable of meeting these requirements.
    As part of this analysis, OSHA reviewed the heat injury and illness 
prevention practices currently in place across the affected industries 
as well as the recommended practices of industry trade associations and 
standards-setting organizations. On the basis of current compliance 
found by OSHA, widespread familiarity with the concepts and procedures 
contained in the proposed rule, and the availability of control 
options, OSHA has determined the requirements of the proposed rule are 
capable of being done by most employers, most of the time and therefore 
preliminarily determined that compliance with the proposed rule is 
technologically feasible.

F. Requests for Comments

    OSHA requests comments on the appropriateness of the preliminary 
determinations contained in this analysis.
    Regarding the feasibility of monitoring, OSHA seeks additional 
comments and information regarding:
     The feasibility of measuring HI in indoor environments and 
where heat-generating processes occur.
     The use of WBGT including the identification of situations 
in which WBGT would or would not be practical or pose challenges for 
employers to measure.
    Regarding the feasibility of controls, OSHA seeks additional 
comments and information on the following:
     Whether there are other controls or technologies that may 
be available to protect workers against heat hazards.
     The technological feasibility of other engineering control 
options not discussed here for indoor, outdoor, and mobile work sites.
     The feasibility of dehumidification as a control option 
for indoor workplaces.
     Areas where employers have determined that isolation of 
heat producing equipment is not feasible and alternatives employers 
have utilized to reduce employee exposures.
     The current use of air-conditioning in the industries 
covered under the scope of the rulemaking.
     Additional ways employers have utilized air-conditioning 
for outdoor workers and obstacles encountered, if any.
     The current use and application of fans in both indoor and 
outdoor settings.
     Work settings where the use of fans is not feasible due to 
contamination concerns and information on what controls, including the 
use of air-conditioning, employers use to prevent HRIs in these 
settings.
     Indoor work settings without heat-generating processes 
that may experience temperatures above 102 [deg]F and information on 
what controls employers implement when fan use is

[[Page 71040]]

contraindicated or when temperatures exceed 102 [deg]F.

X. Additional Requirements

A. Unfunded Mandates Reform Act, 2 U.S.C. 1501 et seq.

    OSHA reviewed this proposed rule according to the Unfunded Mandates 
Reform Act of 1995 (UMRA) (2 U.S.C. 1501 et seq.) and Executive Order 
12875 (58 FR 58093). Section 202 of the UMRA, 2 U.S.C. 1532, requires 
agencies to assess the anticipated costs and benefits of a rule that 
includes a Federal mandate that may result in expenditures in any one 
year by State, local, and Tribal governments, in the aggregate, or by 
the private sector, of at least $100 million, adjusted annually for 
inflation. In 2024, that threshold is $183 million.
    Although OSHA may include compliance costs for affected State Plan 
governmental entities in its analysis of the expected impacts 
associated with a proposal, this proposed rule does not place a mandate 
on State or local government, for purposes of the UMRA. See the 
discussion below in Section X.H., Federalism.
    The OSH Act does not cover Tribal governments in the performance of 
traditional governmental functions, but it does cover Tribal 
governments when they engage in activities of a commercial or service 
character (see Menominee Tribal Enters. v. Solis, 601 F.3d 669 (7th 
Cir. 2010); Reich v. Mashantucket Sand & Gravel, 95 F.3d 174, 180 (2nd 
Cir. 1996)). However, the cost of the proposed rule for these covered 
activities by a Tribal government would not meet the threshold 
established in the UMRA. As noted below, OSHA also reviewed this 
rulemaking in accordance with Executive Order 13175 on Consultation and 
Coordination with Indian Tribal Governments (65 FR 67249 (November 9, 
2000)) and determined that it does not have ``tribal implications'' as 
defined in that Executive Order.
    Based on the analysis presented in the Preliminary Economic 
Analysis and Initial Regulatory Flexibility Analysis, Section VIII. of 
this preamble, OSHA concludes that the proposed rule would impose a 
Federal mandate on the private sector of $100 million or more annually, 
adjusted for inflation. The Preliminary Economic Analysis constitutes 
the written statement containing a qualitative and quantitative 
assessment of the anticipated costs and benefits required under section 
202(a) of the UMRA (2 U.S.C. 1532(a)).

B. Consultation and Coordination With Indian Tribal Governments/
Executive Order 13175

    OSHA reviewed this proposed rule in accordance with Executive Order 
13175, Consultation and Coordination with Indian Tribal Governments, 65 
FR 67249 (Nov. 6, 2000), and determined that it does not have ``tribal 
implications'' as defined in that order. As explained above, the OSH 
Act does not cover Tribal governments in the performance of traditional 
governmental functions, so except to the extent a tribe is engaged in 
activities covered by this proposed rule that would fall outside of a 
traditional government function (i.e., activities of a commercial or 
service character), the proposed rule would not have substantial direct 
effects on one or more Indian tribes in their sovereign capacity, on 
the relationship between the Federal Government and Indian tribes, or 
on the distribution of power and responsibilities between the Federal 
Government and Indian tribes (see E.O. 13175 section 1(a)).
    Section 5 of the Executive Order requires agencies to consult with 
Tribal officials early in the process of developing regulations that: 
(1) have Tribal implications, impose substantial direct compliance 
costs on Indian governments, and are not required by statute; or (2) 
have Tribal implications and preempt Tribal law (E.O. 13175 section 
5(b), (c)). The Executive Order requires that such consultation occur 
to the extent practicable.
    On May 15, 2024, OSHA held a listening session with Tribal 
representatives regarding this Heat Injury and Illness Prevention in 
Outdoor and Indoor Work Settings rulemaking. OSHA provided an overview 
of the rulemaking effort and sought comment on what, if any, Tribal 
implications would result from the rulemaking. A summary of the meeting 
and list of attendees can be viewed in the docket (DOL, 2024a).

C. Consultation With the Advisory Committee on Construction Safety and 
Health

    Under 29 CFR parts 1911 and 1912, OSHA must consult with the 
Advisory Committee on Construction Safety and Health (ACCSH), 
established pursuant to section 107 of the Contract Work Hours and 
Safety Standards Act (40 U.S.C. 3704), in setting standards for 
construction work. Specifically, 29 CFR 1911.10(a) requires the 
Assistant Secretary to provide ACCSH with any proposal (along with 
pertinent factual information) and give ACCSH an opportunity to submit 
recommendations. See also 29 CFR 1912.3(a).
    At a public meeting on April 24, 2024, OSHA presented to ACCSH its 
framework for a proposed rule for heat injury and illness prevention in 
outdoor and indoor work settings. The Committee then passed unanimously 
a motion recommending that OSHA proceed expeditiously with proposing a 
standard on heat injury and illness prevention. The Committee also 
recommended that OSHA consider the feedback and questions discussed by 
Committee members during the meeting in formulating the proposed rule 
(see the minutes from the meeting, Docket No. 2024-0002). OSHA has 
considered the Committee's feedback in the development of this 
proposal.

D. Environmental Impacts

    OSHA reviewed the proposed rule according to the National 
Environmental Policy Act (NEPA) of 1969 (42 U.S.C. 4321 et seq.), the 
regulations of the Council on Environmental Quality (CEQ) (40 CFR 
chapter V, subchapter A), and the Department of Labor's NEPA procedures 
(29 CFR part 11). Pursuant to 29 CFR 11.10 and consistent with CEQ 
regulations, the promulgation, modification, or revocation of any 
safety standard is categorically excluded from the requirement to 
prepare an environmental assessment under NEPA absent extraordinary 
circumstances indicating the need for such an assessment. OSHA finds 
that this proposed rule presents no such extraordinary circumstances.

E. Consensus Standards

    OSHA must consider adopting existing national consensus standards 
that differ substantially from OSHA's proposed standard if the 
consensus standard would better effectuate the purposes of the Act (see 
29 U.S.C. 655(b)(8); see also National Technology Transfer and 
Advancement Act of 1995, Pub. L. 104-113, section 12(d), 15 U.S.C. 272 
Note). Whenever an OSHA rule differs substantially from a national 
consensus standard, OSHA must publish in the Federal Register a 
statement of the reasons why the rule will better effectuate the 
purposes of the Act than the national consensus standard (29 U.S.C. 
655(b)(8)). In the development of the proposed rule, OSHA reviewed the 
ANSI/ASSP national consensus Standard for Heat Stress Management in 
Construction and Demolition Operations, A10.50-2024. Many of the 
proposed provisions are consistent with the ANSI/ASSP standard, 
although there are some

[[Page 71041]]

differences in the details of the provisions, particularly in the scope 
of the standard, as well as requirements for measurements, heat trigger 
levels, hydration, rest breaks, medical surveillance, PPE, 
recordkeeping, and a qualified person.
    Regarding the scope of the standard, while the ANSI/ASSP standard 
applies only to employers in construction and demolition operations, 
the OSHA proposed standard applies to all employers in general 
industry, construction, maritime, and agriculture, with some exceptions 
(as discussed in Section VII.A., Paragraph (a) Scope and application, 
in Section VII., Explanation of Proposed Requirements). While both the 
ANSI/ASSP standard and the OSHA proposed standard would require 
employers to develop a written heat stress management program and 
acclimatization plan, the ANSI/ASSP standard requires a competent 
person to perform a heat stress task hazard analysis and indicates that 
workers' heat exposure should be assessed by use of the WBGT index or 
other heat stress index that accounts for climatic and metabolic heat 
sources and modification of heat transfer from the worker by extra 
clothing or PPE. The OSHA proposed standard requires that employers 
monitor heat conditions but allows employers more flexibility to 
determine workers' heat exposure. For example, in outdoor work areas, 
the OSHA proposed standard allows employers to track local heat index 
forecasts or measure heat index or WBGT, while for indoor work areas 
the OSHA proposed standard requires the employer to identify work areas 
with hazardous heat exposure and develop and implement a monitoring 
plan that includes measurement of heat index or WBGT. For workplaces in 
which employees where vapor-impermeable clothing, the employer's HIIPP 
must specify procedures to protect employees while wearing vapor-
impermeable clothing. OSHA is allowing employers this additional 
flexibility to determine workers' heat exposure through multiple 
options based on feedback from public commenters and small entity 
representatives that WBGT can be technically challenging to measure 
accurately and that, for outdoor work areas, weather forecasts are 
readily available and easy to monitor (see Section IX., Technological 
Feasibility). In addition, with the exception of Minnesota, none of the 
current or proposed heat-specific State regulations rely on WBGT.
    With respect to the heat trigger levels at which certain control 
measures are specified, the ANSI/ASSP standard and OSHA proposed 
standard also deviate slightly. While the ANSI/ASSP standard sets an 
action level of WBGT adjusted for clothing type (clothing-adjusted 
WBGT) of 70 [deg]F or heat index adjusted for radiant heat (adjusted 
heat index) of 80 [deg]F, the OSHA proposed standard specifies an 
initial heat trigger of WBGT equal to the NIOSH RAL or a heat index 
(unadjusted) of 80 [deg]F. The ANSI/ASSP standard's moderate hazard 
action level is a clothing-adjusted WBGT of 80 [deg]F or an adjusted 
heat index of 95 [deg]F, while the OSHA proposed standard specifies a 
high heat trigger of WBGT equal to NISOH REL or a heat index 
(unadjusted) of 90 [deg]F. Additionally, the ANSI/ASSP standard has an 
extreme hazard action level of a clothing-adjusted WBGT of 87 [deg]F or 
an adjusted heat index of 110 [deg]F, at which point ANSI/ASSP 
recommends stopping work that requires high strenuous workload. While 
the ANSI/ASSP and OSHA initial and high heat triggers are similar, OSHA 
is not specifying a third trigger in its proposed standard. This 
decision is in line with recommendations from the SBAR Panel to keep 
the heat triggers simple to understand (see SBAR Panel findings and 
recommendations, Section VIII., Preliminary Economic Analysis and 
Initial Regulatory Flexibility Analysis). Adding a third trigger could 
also add considerable costs. As explained in Section V.B., Basis for 
Initial and High Heat Trigger, OSHA's proposed triggers are based on 
observational and laboratory evidence and, the agency believes, 
represent a highly sensitive and appropriate screening threshold for 
heat stress controls in the workplace. OSHA has preliminarily 
determined that these thresholds are protective for workers and 
achievable for employers.
    With regards to hydration, both the ANSI/ASSP standard and the OSHA 
proposed standard would require that employees have access to suitably 
cool water that is free of charge, in close proximity to working areas, 
and of sufficient quantity. The ANSI/ASSP standard, however, 
additionally requires that employees shall have access to electrolyte 
replenishment beverages when they are involved with heavy work 
activities for greater than two hours. The OSHA proposed standard does 
not have this requirement, as the agency heard from an ACCSH member 
that electrolyte replenishment beverages can contain sugar that cannot 
be consumed by all workers. NIOSH, in its hydration fact sheet, 
recognizes that sports drinks with balanced electrolytes can replace 
salt lost in sweat, but similarly notes that heavy consumption will add 
calories due to the added sugar. NIOSH also points out, ``In general, 
eating regular meals with adequate water is sufficient to maintain 
water and electrolyte balance'' (NIOSH, 2017a). As a result, the OSHA 
proposed rule does not require employers to provide electrolyte 
replenishment beverages but OSHA notes in this preamble that employers 
may provide electrolyte replenishment beverages in addition to water if 
they choose to do so (see Section VII., Explanation of Proposed 
Requirements). OSHA also requests comment on whether the agency should 
require the provision of electrolyte supplements/solutions in addition 
to water.
    Another deviation between the ANSI/ASSP standard and the OSHA 
proposed standard exists in the requirement for rest breaks. While both 
the ANSI/ASSP standard and the OSHA proposed standard require employers 
to provide shaded rest and hydration break areas at or above the action 
level or initial heat trigger, respectively, the ANSI/ASSP standard 
recommends, but does not require, scheduled rest breaks at the moderate 
hazard action level (a clothing-adjusted WBGT or 80 [deg]F or an 
adjusted heat index of 95 [deg]F). OSHA's proposed standard requires 
employers to provide a rest break if needed to prevent overheating at 
or above the initial heat trigger, as well as a rest break of at least 
15 minutes every two hours at or above the high heat trigger. Rest 
breaks, particularly in combination with water and shade, have been 
shown in multiple scientific studies to reduce the risk of heat-related 
fatality and HRI (see Section V.C., Risk Reduction) and therefore OSHA 
is requiring rest breaks in the proposed standard.
    Regarding medical surveillance, the ANSI/ASSP standard indicates 
that a medical surveillance program (e.g., a comprehensive work and 
medical history, a comprehensive physical exam, an assessment of any 
personal risk factors, and the ability to wear PPE) should be 
established for all workers covered by the standard, while the OSHA 
proposed standard does not have a medical surveillance requirement. 
Similarly, while both the ANSI/ASSP standard and the OSHA proposed 
standard require that an employee exhibiting signs or symptoms of heat 
illness be monitored and not left alone or sent home without being 
offered on-site first aid and, if necessary, emergency medical 
services, the ANSI/ASSP standard further requires that a supervisor or 
team member be trained in first aid and certified in cardiopulmonary 
resuscitation (CPR) and the use of the automated external defibrillator 
(AED) when a medical

[[Page 71042]]

professional is not available on-site. Due to the widespread scope of 
the OSHA proposed standard, the agency believes that a requirement for 
medical surveillance or for certification of supervisors or team 
members in CPR and AED would be impractical and could add considerable 
costs. In addition, OSHA also heard a comment from a construction 
industry representative during the ACCSH consultation that requiring 
medical surveillance would also be logistically difficult (see the 
minutes from the meeting, Docket No. 2024-0002).
    With respect to PPE, the ANSI/ASSP standard requires the 
implementation of heat stress controls following the hierarchy of 
controls, with engineering controls implemented first, followed by 
administrative controls, and then cooling PPE. While the OSHA proposed 
standard specifies the use of engineering controls and administrative 
controls, it does not require the use of cooling PPE. OSHA believes 
that cooling PPE--such as a cooling vest--has the potential to become 
hazardous as the cooling properties dissipate. As a result, the OSHA 
proposed standard requires that employers who choose to provide cooling 
PPE to their employees ensure that the cooling properties of the PPE 
are maintained at all times during use (see Section VII.E., Paragraph 
(e) Requirements at or above the Initial Heat Trigger).
    With regards to recordkeeping, the ANSI/ASSP standard requires 
employers to keep a written inventory of local conditions at the work 
site that affect or increase the potential for heat stress only as long 
as the hazard exists or as required by law. The OSHA proposed standard 
is more specific, requiring that employers maintain written or 
electronic records of indoor work area measurements for 6 months (see 
Section VII.I., Paragraph (i) Recordkeeping). OSHA believes this 
specificity increases clarity for employers.
    Finally, the ANSI/ASSP standard requires a qualified person ``who, 
by possession of a recognized degree, certificate, or professional 
standing, or who by extensive knowledge, training, and experience, has 
successfully demonstrated the ability to solve or resolve problems 
relating to the subject matter, the work, or the project.'' The ANSI/
ASSP standard requires that the qualified person assist with the 
development and review of the heat stress management program, the use 
and interpretation of the WBGT, and the development and review of the 
first aid and emergency action plan, as well as providing guidance or 
in-person support to the competent person on implementation of the 
program as needed. The OSHA proposed standard does not have a 
requirement for a qualified person. Due to the widespread scope of the 
proposed standard, OSHA does not believe that it would be feasible to 
require all covered employers to hire a qualified person as 
contemplated by the ANSI/ASSP standard. Instead, the proposed standard 
requires the designation of one or more heat safety coordinators who 
are trained in and responsible for ensuring compliance with all 
requirements of the employer's HIIPP. OSHA also plans to provide 
compliance assistance materials such as a model HIIPP and other 
materials.
    OSHA also notes that there are some requirements in its proposed 
standard that are not required by the ANSI/ASSP standard. Specifically, 
the OSHA proposed standard contains a hazard alert provision that 
requires employers to notify employees that the high heat trigger has 
been met or exceeded (see Section VII.F., Paragraph (f) Requirements at 
or above the High Heat Trigger). The OSHA proposed standard also 
requires that employers place warning signs at indoor areas with 
ambient temperatures that regularly exceed 120[deg]F (see Section 
VII.F., Paragraph (f) Requirements at or above the High Heat Trigger). 
OSHA believes that these additional requirements are important for the 
protection of workers from heat hazards in the workplace.
    OSHA has preliminarily determined that the proposed standard would 
be highly effective at addressing the risk of occupational heat 
exposure while remaining workable across the many different work 
contexts covered by the proposal. As such, OSHA believes that the 
standard as proposed will best effectuate the OSH Act's purpose of 
ensuring safe and healthful working conditions.

F. Incorporation by Reference

    OSHA is proposing to incorporate by reference NIOSH Publication No. 
2016-106. Criteria for a Recommended Standard: Occupational Exposure to 
Heat and Hot Environments, February 2016. In this publication, NIOSH 
provides recommendations for an occupational standard for workers 
exposed to heat, including the NIOSH Recommended Alert Limit (RAL) and 
Recommended Exposure Limit (REL). OSHA is proposing the RAL as an 
option for the initial heat trigger and the REL as an option for the 
high heat trigger (see Section VII.B., Paragraph (b) Definitions).
    NIOSH Publication No. 2016-106 is available to download for free on 
NIOSH's website (https://www.cdc.gov/niosh/docs/2016-106) and linked 
from OSHA's website (https://www.osha.gov/heat-exposure/standards). It 
is also available in the rulemaking docket for this proposed standard 
(Docket ID OSHA-2021-0009-0050).

G. Protection of Children From Environmental Health Risks and Safety 
Risks

    Executive Order 13045, on Protection of Children from Environmental 
Health Risks and Safety Risks, as amended by Executive Orders 13229 and 
13296, requires that Federal agencies provide additional evaluation of 
economically significant regulatory actions that concern an 
environmental health or safety risk that an agency has reason to 
believe may disproportionately affect children. This proposed rule is 
intended to protect United States workers from occupational hazards. 
OSHA has preliminarily determined that the proposed rule will not 
disproportionately affect children or have any adverse impact on 
children. Because workers in the industries covered by this proposed 
rule may include older children, the proposed rule could have a 
protective effect on these older children in the workforce by reducing 
the possibility of heat-related injury or illness. Accordingly, E.O. 
13045, Protection of Children from Environmental Health Risks and 
Safety Risks, requires no further agency action or analysis.

H. Federalism

    The agency reviewed this proposed rule in accordance with Executive 
Order 13132 on Federalism (64 FR 43255, (August 10, 1999)), which, 
among other things, is intended to ``ensure that the principles of 
federalism established by the Framers guide the executive departments 
and agencies in the formulation and implementation of policies.'' The 
E.O. generally allows Federal agencies to preempt State law only as 
provided by Congress or where State law conflicts with Federal law. In 
such cases, Federal agencies must limit preemption of State law to the 
extent possible. The E.O. also requires that agencies consult with 
States on rules that have ``federalism implications,'' which are those 
that have ``substantial direct effects on the States, on the 
relationship between the national government and the States, or on the 
distribution of power and responsibilities among the various levels of 
government.''

[[Page 71043]]

    This proposed rule complies with E.O. 13132. The hazards addressed 
by this proposed rule and its goal of protecting workers from exposure 
to hazardous heat are national in scope and the proposed rule does not 
include ``federalism implications'' as defined in the E.O. Under 
section 18 of the OSH Act (29 U.S.C. 667), Congress expressly provided 
that States may adopt, with Federal approval, a plan for the 
development and enforcement of occupational safety and health 
standards. OSHA refers to the occupational safety and health plans that 
have been submitted by States and approved by OSHA as ``State Plans.'' 
Occupational safety and health standards developed by States with OSHA-
approved State Plans must be at least as effective in providing safe 
and healthful employment and places of employment as the Federal 
standards. Subject to these requirements, these States are free to 
develop and enforce their own occupational safety and health standards. 
The choice to adopt a State Plan is part of the statutory scheme and is 
not mandatory, so there are no federalism implications for States that 
choose to do so.
    In States without OSHA-approved State Plans, the States are not 
employers under to the OSH Act and the proposed rule would therefore 
not have a substantial direct effect on them (29 U.S.C. 652(5)). The 
following section addresses the effect of the proposed rule on States 
with OSHA-approved State Plans.

I. Requirements for States With OSHA-Approved State Plans

    When Federal OSHA promulgates a new standard or a more stringent 
amendment to an existing standard, States and U.S. Territories with 
OSHA-approved State Plans must either amend their standards to be 
identical to or ``at least as effective as'' the new standard or 
amendment or show that an existing State Plan standard covering this 
area is already ``at least as effective'' as the new Federal standard 
or amendment (29 CFR 1953.5(b)). State Plan adoption must be completed 
within six months of the promulgation date of the final Federal rule.
    Of the 29 States and Territories with OSHA-approved State Plans, 22 
cover both public and private-sector employees: Alaska, Arizona, 
California, Hawaii, Indiana, Iowa, Kentucky, Maryland, Michigan, 
Minnesota, Nevada, New Mexico, North Carolina, Oregon, Puerto Rico, 
South Carolina, Tennessee, Utah, Vermont, Virginia, Washington, and 
Wyoming. The remaining seven States and Territories cover only State 
and local government employees: Connecticut, Illinois, Maine, 
Massachusetts, New Jersey, New York, and the Virgin Islands.
    OSHA preliminarily concludes that this proposed rule would increase 
protections beyond those provided by most current standards in State 
Plans. Therefore, within six months of any final rule's promulgation 
date, States with OSHA-approved State Plans would be required to adopt 
standards that are identical to or ``at least as effective'' as this 
rule, unless they demonstrate that such amendments are not necessary 
because their existing permanent standards are already ``at least as 
effective'' in protecting workers. OSHA seeks comment on this 
assessment of its proposal.

J. OMB Review Under the Paperwork Reduction Act of 1995

A. Overview
    The proposed Heat Injury and Illness Prevention Standard contains 
collection-of -information requirements that are subject to the Office 
of Management and Budget (OMB) review and approval under the Paperwork 
Reduction Act of 1995 (PRA), 44 U.S.C. 3501 et seq. and its 
implementing regulations at 5 CFR part 1320. The PRA defines a 
collection-of-information as the obtaining, causing to be obtained, 
soliciting, or requiring the disclosure to third parties or the public 
of facts or opinions by or for an agency regardless of form or format. 
(See 44 U.S.C. 3502(3)(A)). The collection of information requirements 
specified in the proposal would reduce the risk of death, serious 
injury, and illness by ensuring that employers develop and implement a 
worksite heat injury and illness prevention plan (HIIPP), review and 
evaluate the effectiveness of the HIIPP, designate one or more heat 
safety coordinators to implement and monitor the HIIPP, and develop and 
implement a heat illness emergency response plan to respond to 
employees experiencing signs and symptoms of heat related illnesses for 
indoor and outdoor conditions. OSHA is requesting OMB approval of the 
proposed Information Collection Request (ICR) and a new OMB Control 
Number for this ICR currently under OMB Control Number 1218-0NEW.
    Under the PRA, a Federal agency cannot conduct or sponsor a 
collection of information unless OMB approves it, and the agency 
displays a currently valid OMB control number (44 U.S.C. 3507). Also, 
notwithstanding any other provision of law, no employer shall be 
subject to penalty for failing to comply with a collection of 
information if the collection of information does not display a 
currently valid OMB control number (44 U.S.C. 3512).
B. Solicitation of Comments
    In accordance with the PRA (44 U.S.C. 3506(c)(2) and 3507(d)), OSHA 
submitted the collection-of-information requirements identified in the 
NPRM to OMB for review. The agency solicits comments on the collection-
of-information requirements and estimated burden hours associated with 
these requirements, including comments on the following items:
     Whether the proposed collections of information are 
necessary for the proper performance of the agency's functions, 
including whether the information is useful;
     The accuracy of OSHA's estimate of the burden (time and 
cost) of the proposed collections of information, including the 
validity of the methodology and assumptions used;
     The quality, utility, and clarity of the information 
collected; and
     Ways to minimize the compliance burden on employers, for 
example, by using automated or other technological techniques for 
collecting and transmitting information (78 FR 56438).
C. Proposed Collection of Information Requirements
    As required by 5 CFR 1320.5(a)(1)(iv) and 1320.8(d)(1), the 
following paragraphs provide information about this ICR.
    1. Title: Heat Injury and Illness Prevention Standard (29 CFR 
1910.148).
    2. Description of the ICR: The proposal would add new collection-
of-information requirements to protect indoor and outdoor workers from 
hazardous heat.
    3. Brief Summary of the Collection of Information Requirements: The 
proposed Heat Injury and Illness Prevention Standard ICR adds new 
collection-of-information requirements that would ensure that employers 
develop and implement a worksite heat injury and illness prevention 
plan, review and evaluate the effectiveness of the HIIPP, designate one 
or more heat safety coordinators to implement and monitor the HIIPP, 
and develop and implement a heat illness emergency response plan for 
employees experiencing signs and symptoms of heat related illnesses for 
indoor and outdoor workers. Specifically, the proposed collection-of-
information requirements contained in the proposed rule for the Heat 
Injury and Illness Prevention Standard are listed in table X.J-1.

[[Page 71044]]



  Table X.J-1--Proposed Collection-of-Information Requirements for Heat
                      Injury and Illness Prevention
------------------------------------------------------------------------
               Section          Collection-of-information requirements
------------------------------------------------------------------------
1        Sec.                Paragraphs (c)(1) through (4) would require
          1910.148(c)(1)      employers to develop and implement a heat
          through (4).        injury and illness prevention plan
                              (HIIPP), which must include a list of
                              covered activities, the policies and
                              procedures necessary to comply with the
                              proposed standard, the heat metric the
                              employer will use to comply with paragraph
                              (d), and policies and procedures related
                              to the use of vapor-impermeable clothing,
                              if applicable. For employers with more
                              than 10 employees, the HIIPP must be in
                              writing.
2        Sec.                Paragraph (c)(5) would require the employer
          1910.148(c)(5).     to designate one or more heat safety
                              coordinators to implement and monitor the
                              HIIPP.
3        Sec.                Paragraphs (c)(6) and (7) would require the
          1910.148(c)(6)      employer to seek the input and involvement
          and (7).            of non-managerial employees in the
                              development and implementation of the
                              HIIPP, and to review and evaluate the
                              effectiveness of the HIIPP at least
                              annually and whenever a heat-related
                              illness or injury occurs that results in
                              days away from work, medical treatment
                              beyond first aid, or loss of
                              consciousness.
4        Sec.                Paragraphs (c)(8) and (9) would require the
          1910.148(c)(8)      employer to make the HIIPP readily
          and (9).            available at the work site in a language
                              each employee, supervisor, and heat safety
                              coordinator understands.
5        Sec.                Paragraph (d)(3) would require the
          1910.148(d)(3).     employer, at indoor work sites, to
                              identify each work area(s) where there is
                              a reasonable expectation that employees
                              are or may be exposed to heat at or above
                              the initial heat trigger. For each work
                              area identified, the employer would be
                              required to develop and implement a
                              monitoring plan that includes measuring
                              heat index or wet bulb globe temperature.
                              Employers would also be required to
                              evaluate any affected work area(s) and
                              update their monitoring plan whenever
                              there is a change in production,
                              processes, equipment, controls, or a
                              substantial increase in outdoor
                              temperature which has the potential to
                              increase heat exposure indoors. The
                              employer would be required to seek the
                              input and involvement of non-managerial
                              employees when identifying work areas with
                              a reasonable expectation of exposure at or
                              above the initial heat trigger and in
                              developing and updating monitoring plans.
6        Sec.                Paragraph (e)(7) would require the
          1910.148(e)(7).     employer, when the initial heat trigger is
                              met or exceeded, to implement an
                              acclimatization protocol for each new
                              employee and each returning employee
                              (i.e., who has been away from work for
                              more than 14 days) during their first week
                              on the job. Employers would be required to
                              choose either a plan that would
                              incorporate the control measures required
                              when the high heat trigger is met or
                              exceeded, or a gradual acclimatization
                              plan that would slowly increase the
                              employee's exposure to heat each day. The
                              requirement would not apply if the
                              employer can demonstrate that the employee
                              consistently worked under the same or
                              similar conditions within the past 14
                              days.
7        Sec.                Paragraph (e)(9) would require the
          1910.148(e)(9).     employer, when the initial heat trigger is
                              met or exceeded, to maintain a means of
                              effective, two-way communication with
                              employees and regularly communicate with
                              employees.
8        Sec.                Paragraph (f)(4) would require the
          1910.148(f)(4).     employer, prior to the work shift or upon
                              determining that the high heat trigger is
                              met or exceeded, to notify employees of
                              the importance of drinking plenty of
                              water, employees' right to take rest
                              breaks if needed and required rest breaks,
                              how to seek help and the procedures to
                              take in a heat emergency, and, for mobile
                              work sites, the location of break area(s)
                              and drinking water.
9        Sec.                Paragraph (f)(5) would require the employer
          1910.148(f)(5).     to place a legible, visible, and
                              understandable warning sign at indoor work
                              areas with ambient temperatures that
                              regularly exceed 120 [deg]F.
10       Sec.                Paragraph (g)(1) would require employers,
          1910.148(g)(1).     as part of their HIIPP, to develop and
                              implement a heat emergency response plan
                              that includes a list of emergency phone
                              numbers, a description of how employees
                              can contact a supervisor and emergency
                              medical services, individual(s) designated
                              to ensure that heat emergency procedures
                              are invoked when appropriate, a
                              description of how to transport employees
                              to a place where they can be reached by
                              emergency medical services, clear and
                              precise directions to the work site, and
                              procedures for responding to an employee
                              experiencing signs and symptoms of heat-
                              related illness or a heat emergency.
11       Sec.                Paragraph (g)(3) would require the
          1910.148(g)(3).     employer, if an employee is experiencing
                              signs and symptoms of a heat emergency, to
                              take immediate actions to reduce the
                              employee's body temperature and
                              immediately contact emergency medical
                              services, as well as relieving them from
                              duty, monitoring them, ensuring they are
                              not left alone, and offering them on-site
                              first aid and medical services.
12       Sec.                Paragraph (i)(1) would require employers to
          1910.148(i)(1).     have written or electronic records of on-
                              site measurements at indoor work areas,
                              and to retain those records for 6 months.
------------------------------------------------------------------------

    4. OMB Control Number: 1218-0NEW.
    5. Affected Public: Business or other for-profit.
    6. Number of Respondents: 2,535,775.
    7. Frequency of Responses: On occasion, annually.
    8. Number of Responses: 1,699,783,434.
    9. Average Time per Response: Varies.
    10. Estimated Total Burden Hours: 27,803,599.
    11. Estimated Costs (capital-operation and maintenance): 
$24,040,064.

D. Submitting Comments

    Members of the public may comment on the collection of information 
requirements in this proposed standard by sending their comments to the 
Office of Information and Regulatory Affairs, Attn: OMB Desk Officer 
for the Department of Labor, OSHA Regulation Identifier Number (RIN) 
(1218-AD39), by email: [email protected]. Please limit the 
comments to only those addressing the collection of information 
requirements in the proposed Heat Injury and Illness Prevention 
standard (i.e., proposed Sec.  1910.148). OSHA encourages commenters 
also to submit their comments on these collection of information 
requirements to the rulemaking docket (OSHA-2021-0009), along with 
their comments on other parts of the proposed standard. For 
instructions on submitting these comments to the docket, see the 
sections of this Federal Register document titled DATES and ADDRESSES. 
Comments submitted in response to this document are public records; 
therefore, OSHA cautions commenters about submitting personal 
information, such as Social Security numbers and dates of birth.

[[Page 71045]]

E. Docket and Inquiries

    To access the docket to read or download comments and other 
materials related to this paperwork determination, including the 
complete ICR, use the procedures described under the section of this 
document titled ADDRESSES. You may obtain an electronic copy of the 
complete ICR by going to the website at https://www.reginfo.gov/public/do/PRAMain, then select ``Department of Labor'' under ``Currently Under 
Review``, then click on ``submit''. This will show all of the 
Department's ICRs currently under review, including the ICRs submitted 
for proposed rulemakings. To make inquiries, or to request other 
information, contact Ms. Seleda Perryman, Directorate of Standards and 
Guidance, Occupational Safety and Health Administration, U.S. 
Department of Labor; telephone (202) 693-4131; email 
[email protected].

XI. Authority and Signature

    This document was prepared under the direction of Douglas L. 
Parker, Assistant Secretary of Labor for Occupational Safety and 
Health, U.S. Department of Labor, 200 Constitution Ave. NW, Washington, 
DC 20210. It is issued under the authority of sections 4, 6, and 8 of 
the Occupational Safety and Health Act of 1970 (29 U.S.C. 653,655, and 
657); 5 U.S.C. 553, Secretary of Labor's Order No. 8-2020 (85 FR 
58383), and 29 CFR part 1911.

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List of Subjects in 29 CFR Parts 1910, 1915, 1917, 1918, 1926, and 
1928

    Heat-related injuries and illnesses, Heat stress, Incorporation by 
reference, Occupational safety and health, Safety.

    Signed at Washington, DC.
Douglas L. Parker,
Assistant Secretary of Labor for Occupational Safety and Health.

Amendments to Standards

    For the reasons set forth in the preamble, OSHA proposes to amend 
29 CFR parts 1910, 1915, 1917, 1918, 1926, and 1928 as follows:

PART 1910--OCCUPATIONAL SAFETY AND HEALTH STANDARDS

Subpart A--General

0
1. The authority citation for part 1910, subpart A, is revised to read 
as follows:

    Authority: 29 U.S.C. 653, 655, 657; Secretary of Labor's Order 
No. 12-71 (36 FR 8754), 8-76 (41 FR 25059), 9-83 (48 FR 35736), 1-90 
(55 FR 9033), 6-96 (62 FR 111), 3-2000 (65 FR 50017), 5-2002 (67 FR 
65008), 5-2007 (72 FR 31159), 4-2010 (75 FR 55355), 1-2012 (77 FR 
3912), or 8-2020 (85 FR

[[Page 71069]]

58393), as applicable. Sections 1910.6, 1910.7, 1910.8 and 1910.9 
also issued under 29 CFR 1911. Section 1910.7(f) also issued under 
31 U.S.C. 9701; 29 U.S.C. 9a; 5 U.S.C. 553; Public Law 106-113 (113 
Stat. 1501A-222); Public Law 11-8 and 111-317; and OMB Circular A-25 
(dated July 8, 1993) (58 FR 38142, July 15, 1993).

0
2. Amend Sec.  1910.6 to subpart A by revising the introductory text of 
paragraph (z) and adding paragraph (z)(4) to read as follows:


Sec.  1910.6  Incorporation by reference.

* * * * *
    (z) National Institute for Occupational Safety and Health (NIOSH), 
1600 Clifton Road, Atlanta, GA 30329; website: www.cdc.gov/niosh.
* * * * *
    (4) NIOSH Publication No. 2016-106. Criteria for a Recommended 
Standard: Occupational Exposure to Heat and Hot Environments, February 
2016; IBR approved for Sec.  1910.148(b).
* * * * *

Subpart J--General Environmental Controls

0
3. The authority citation for part 1910, subpart J, is revised to read 
as follows:

    Authority: 29 U.S.C. 653, 655, 657; Secretary of Labor's Order 
No. 12-71 (36 FR 8754), 8-76 (41 FR 25059), 9-83 (48 FR 35736), 1-90 
(55 FR 9033), 6-96 (62 FR 111), 3-2000 (65 FR 50017), 5-2002 (67 FR 
65008), 5-2007 (72 FR 31159), 4-2010 (75 FR 55355), 1-2012 (77 FR 
3912) or 8-2020 (85 FR 58393), as applicable.
    Sections 1910.141, 1910.142, 1910.145, 1910.146, 1910.147, and 
1910.148 also issued under 29 CFR part 1911.

0
4. Add Sec.  1910.148 to subpart J to read as follows:


Sec.  1910.148  Heat Injury and Illness Prevention.

    (a) Scope and application. (1) Except as otherwise provided in this 
paragraph (a), this standard applies to all employers.
    (2) This standard does not apply to the following:
    (i) Work activities for which there is no reasonable expectation of 
exposure at or above the initial heat trigger;
    (ii) Short duration employee exposures at or above the initial heat 
trigger of 15 minutes or less in any 60-minute period;
    (iii) Organizations whose primary function is the performance of 
firefighting; emergency response activities of workplace emergency 
response teams, emergency medical services, or technical search and 
rescue; and any emergency response activities already covered under 29 
CFR 1910.120, 1910.146, 1910.156, part 1915, subpart P, 1926.65, and 
1926.1211;
    (iv) Work activities performed in indoor work areas or vehicles 
where air-conditioning consistently keeps the ambient temperature below 
80 [deg]F;
    (v) Telework (i.e., work done from home or another remote location 
of the employee's choosing); and
    (vi) Sedentary work activities at indoor work areas that only 
involve some combination of the following: sitting, occasional standing 
and walking for brief periods of time, and occasional lifting of 
objects weighing less than 10 pounds.
    (3) Employers whose employees all exclusively perform activities 
described in paragraphs (a)(2)(i) through (vi) of this section are 
exempt from this standard.
    (b) Definitions. The following definitions apply to this standard:
    Acclimatization means the body's adaptation to work in the heat as 
a person is exposed to heat gradually over time, which reduces the 
strain caused by heat stress and enables a person to work with less 
chance of heat illness or injury.
    Ambient temperature means the temperature of the air surrounding a 
body. It is also called ``air temperature'' or ``dry bulb 
temperature.''
    Cooling personal protective equipment (PPE) means equipment worn to 
protect the user against heat injury or illness.
    Heat index means the National Weather Service heat index, which 
combines ambient temperature and humidity.
    High heat trigger means a heat index of 90 [deg]F or a wet bulb 
globe temperature equal to the National Institute for Occupational 
Safety and Health (NIOSH) Recommended Exposure Limit (REL).
    Indoor/indoors means an area under a ceiling or overhead covering 
that restricts airflow and has along its entire perimeter walls, doors, 
windows, dividers, or other physical barriers that restrict airflow, 
whether open or closed.
    Initial heat trigger means a heat index of 80 [deg]F or a wet bulb 
globe temperature equal to the NIOSH Recommended Alert Limit (RAL).
    Outdoor/outdoors means an area that is not indoors. For purposes of 
this standard, vehicles operated outdoors are considered outdoor work 
areas unless exempted by paragraph (a)(2) of this section.
    Radiant heat means heat transferred by electromagnetic waves 
between surfaces. Sources of radiant heat include the sun, hot objects, 
hot liquids, hot surfaces, and fire.
    Recommended Alert Limit (RAL) means the NIOSH-recommended heat 
stress alert limits for unacclimatized workers, see NIOSH Publication 
No. 2016-106 (incorporated by reference, see Sec.  1910.6).
    Recommended Exposure Limit (REL) means the NIOSH-recommended heat 
stress exposure limits for acclimatized workers, see NIOSH Publication 
No. 2016-106 (incorporated by reference, see Sec.  1910.6).
    Shade means the blockage of direct sunlight, such that objects do 
not cast a shadow in the area of blocked sunlight.
    Signs and symptoms of a heat emergency means the physiological 
manifestations of a heat-related illness that requires emergency 
response and includes loss of consciousness (i.e., fainting, collapse) 
with excessive body temperature, which may or may not be accompanied by 
vertigo, nausea, headache, cerebral dysfunction, or bizarre behavior. 
This could also include staggering, vomiting, acting irrationally or 
disoriented, having convulsions, and (even after resting) having an 
elevated heart rate.
    Signs and symptoms of heat-related illness means the physiological 
manifestations of a heat-related illness and includes headache, nausea, 
weakness, dizziness, elevated body temperature, muscle cramps, and 
muscle pain or spasms.
    Vapor-impermeable clothing means full-body clothing that 
significantly inhibits or completely prevents sweat produced by the 
body from evaporating into the outside air. Examples include 
encapsulating suits, various forms of chemical resistant suits, and 
other forms of nonbreathable PPE.
    Vehicle means a car, truck, van, or other motorized means of 
transporting people or goods.
    Wet bulb globe temperature (WBGT) means a heat metric that takes 
into account ambient temperature, humidity, radiant heat from sunlight 
or artificial heat sources, and air movement.
    Work area means an area where one or more employees are working 
within a work site.
    Work site means a physical location (e.g., fixed, mobile) where the 
employer's work or operations are performed.
    (c) Heat injury and illness prevention plan. (1) The employer must 
develop and implement a work site heat injury and illness prevention 
plan (HIIPP) with site-specific information.
    (2) The HIIPP must include:
    (i) A comprehensive list of the types of work activities covered by 
the plan;
    (ii) All policies and procedures necessary to comply with the 
requirements of this standard; and

[[Page 71070]]

    (iii) An identification of the heat metric (i.e., heat index or wet 
bulb globe temperature) the employer will monitor to comply with 
paragraph (d) of this section.
    (3) If the employer has employees who wear vapor-impermeable 
clothing, the employer must evaluate heat stress hazards resulting from 
these clothing and implement policies and procedures based on reputable 
sources to protect employees while wearing these clothing. The employer 
must include these policies and procedures and document the evaluation 
in the HIIPP.
    (4) If the employer has more than 10 employees, the HIIPP must be 
written.
    (5) The employer must designate one or more heat safety 
coordinators to implement and monitor the HIIPP. The identity of the 
heat safety coordinator(s) must be documented in any written HIIPP. The 
heat safety coordinator(s) must have the authority to ensure compliance 
with all aspects of the HIIPP.
    (6) The employer must seek the input and involvement of non-
managerial employees and their representatives, if any, in the 
development and implementation of the HIIPP.
    (7) The employer must review and evaluate the effectiveness of the 
HIIPP whenever a heat-related illness or injury occurs that results in 
death, days away from work, medical treatment beyond first aid, or loss 
of consciousness, but at least annually. Following each review, the 
employer must update the HIIPP as necessary. The employer must seek 
input and involvement of non-managerial employees and their 
representatives, if any, during any reviews and updates.
    (8) The employer must make the HIIPP readily available at the work 
site to all employees performing work at the work site.
    (9) The HIIPP must be available in a language each employee, 
supervisor, and heat safety coordinator understands.
    (d) Identifying heat hazards--(1) Outdoor work. The employer must 
monitor heat conditions at outdoor work areas by:
    (i) Tracking local heat index forecasts provided by the National 
Weather Service or other reputable sources; or
    (ii) At or as close as possible to the work area(s), measuring the 
following:
    (A) Heat index, or ambient temperature and humidity measured 
separately to calculate heat index; or
    (B) Wet bulb globe temperature.
    (2) Frequency of outdoor monitoring. The employer must monitor with 
sufficient frequency to determine with reasonable accuracy employees' 
exposure to heat.
    (3) Indoor work. (i) At indoor work sites, the employer must 
identify each work area(s) where there is a reasonable expectation that 
employees are or may be exposed to heat at or above the initial heat 
trigger.
    (ii) The employer must develop and implement a monitoring plan 
covering each work area identified in paragraph (d)(3)(i) of this 
section to determine when employees are exposed to heat at or above the 
initial and high heat triggers. The employer must include the 
monitoring plan in the HIIPP and the monitoring plan must include 
measuring one of the following at or as close as possible to the work 
area(s) identified in paragraph (d)(3)(i) of this section:
    (A) Heat index, or ambient temperature and humidity measured 
separately to calculate heat index; or
    (B) Wet bulb globe temperature.
    (iii) Whenever there is a change in production, processes, 
equipment, controls, or a substantial increase in outdoor temperature 
which has the potential to increase heat exposure indoors, the employer 
must evaluate any affected work area(s) to identify where there is 
reasonable expectation that employees are or may be exposed to heat at 
or above the initial heat trigger. The employer must update their 
monitoring plan or develop and implement a monitoring plan, in 
accordance with paragraph (d)(3)(ii) of this section, to account for 
any increases in heat exposure.
    (iv) The employer must seek the input and involvement of non-
managerial employees and their representatives, if any, when evaluating 
the work site to identify work areas with a reasonable expectation of 
exposures at or above the initial heat trigger and in developing and 
updating monitoring plans in accordance with paragraphs (d)(3)(i) 
through (iii) of this section.
    (4) Heat metric. The heat metric the employer chooses to monitor 
will determine the applicable initial and high heat triggers for 
purposes of this standard. If the employer does not identify their 
choice of heat metric in the HIIPP or monitor as required by paragraph 
(d) of this section, the initial and high heat triggers will be the 
heat index values identified in the definitions.
    (5) Exemption from monitoring. The employer can assume that the 
temperature at a work area is at or above both the initial heat and 
high heat triggers instead of conducting on-site measurements or 
tracking local forecasts. In such cases, the employer must provide all 
control measures outlined in paragraphs (e) and (f) of this section.
    (e) Requirements at or above the initial heat trigger--(1) Timing. 
The employer must implement the controls described in this paragraph 
(e) when employees are exposed to heat at or above the initial heat 
trigger.
    (2) Drinking water. The employer must provide access to potable 
water for drinking that is:
    (i) Placed in locations readily accessible to the employee;
    (ii) Suitably cool; and
    (iii) Of sufficient quantity to provide access to 1 quart of 
drinking water per employee per hour.

    Note 1 to paragraph (e)(2).  The requirements of this paragraph 
(e)(2) are in addition to the requirements in the sanitation 
standard applicable to the employer (29 CFR 1910.141, 1915.88, 
1917.127, 1918.95, 1926.51, 1928.110) and the temporary labor camps 
standard (29 CFR 1910.142).

    (3) Break area(s) at outdoor work sites. The employer must provide 
one or more area(s) for employees to take breaks that can accommodate 
the number of employees on break, is readily accessible to the work 
area(s), and has at least one of the following:
    (i) Artificial shade (e.g., tent, pavilion) or natural shade (e.g., 
trees), but not shade from equipment, that provides blockage of direct 
sunlight and is open to the outside air; or
    (ii) Air-conditioning, if in an enclosed space like a trailer, 
vehicle, or structure.
    (4) Break area(s) at indoor work sites. The employer must provide 
one or more area(s) for employees to take breaks (e.g., break room) 
that is air-conditioned or has increased air movement and, if 
appropriate, de-humidification, can accommodate the number of employees 
on break, and is readily accessible to the work area(s).
    (5) Indoor work area controls. The employer must provide one of the 
following at each work area identified in paragraph (d)(3)(i) of this 
section:
    (i) Increased air movement, such as fans or comparable natural 
ventilation, and, if appropriate, de-humidification;
    (ii) Air-conditioned work area; or
    (iii) In cases of radiant heat sources, other measures that 
effectively reduce employee exposure to radiant heat in the work area 
(e.g., shielding/barriers, isolating heat sources).
    (6) Evaluation of fan use. At ambient temperatures above 102 
[deg]F, if the employer is providing fans to comply with paragraph 
(e)(4) or (5) of this section, the employer must evaluate the humidity 
to determine if fan use is harmful, and if the employer determines

[[Page 71071]]

that it is, the employer must discontinue fan use.
    (7) Acclimatization--(i) New employees. The employer must implement 
one of the following acclimatization protocols for each employee during 
their first week on the job:
    (A) A plan that, at minimum, incorporates the measures in paragraph 
(f) of this section whenever the heat index is at or above the initial 
heat trigger during the employee's first week of work; or
    (B) Gradual acclimatization to heat in which the employee's 
exposure to heat is restricted to no more than: 20% of a normal work 
shift exposure duration on the first day of work, 40% on the second day 
of work, 60% of the third day of work, and 80% on the fourth day of 
work.
    (ii) Returning employees. The employer must implement one of the 
following acclimatization protocols for each employee who has been away 
(e.g., on vacation or sick leave) for more than 14 days during their 
first week back on the job:
    (A) A plan that, at minimum, incorporates the measures in paragraph 
(f) of this section whenever the heat index is at or above the initial 
heat trigger during the employee's first week upon returning to work; 
or
    (B) Gradual acclimatization to heat in which employee exposure to 
heat is restricted to no more than: 50% of a normal work shift exposure 
duration on the first day of work, 60% on the second day of work, and 
80% of the third day of work.
    (iii) Exception to acclimatization requirements. The requirements 
of paragraphs (e)(7)(i) and (ii) of this section do not apply if the 
employer can demonstrate the employee consistently worked under the 
same or similar conditions as the employer's working conditions within 
the prior 14 days.
    (8) Rest breaks if needed. The employer must allow and encourage 
employees to take paid rest breaks in the break area required by 
paragraph (e)(3) or (4) of this section if needed to prevent 
overheating.
    (9) Effective communication. The employer must maintain a means of 
effective, two-way communication with employees (e.g., by voice or 
electronic means (such as a handheld transceiver, phone, or radio)) and 
regularly communicate with employees.
    (10) Personal protective equipment (PPE). If the employer provides 
employees with cooling PPE, the employer must ensure the cooling 
properties of the PPE are maintained at all times during use.
    (f) Requirements at or above the high heat trigger--(1) Timing. In 
addition to the controls required by paragraph (e) of this section, the 
employer must implement the controls described in this paragraph (f) 
when employees are exposed to heat at or above the high heat trigger.
    (2) Rest breaks. The employer must provide employees a minimum 15-
minute paid rest break at least every two hours in the break area 
required by paragraph (e)(3) or (4) of this section, subject to the 
following:
    (i) A meal break may count as a rest break, even if it is not 
otherwise required by law to be paid;
    (ii) Periods during which employees are donning and doffing 
personal protective equipment (e.g., coveralls) must not count towards 
the total time provided for rest breaks; and
    (iii) The time for employees to walk to and from the break area is 
not included in the time provided for rest breaks.
    (3) Observation for signs and symptoms. The employer must implement 
at least one of the following methods of observing employees for signs 
and symptoms of heat-related illness:
    (i) A mandatory buddy system in which co-workers observe each 
other; or
    (ii) Observation by a supervisor or heat safety coordinator, with 
no more than 20 employees observed per supervisor or heat safety 
coordinator.
    (iii) For employees who are alone at a work site, the employer must 
maintain a means of effective, two-way communication with those 
employees (e.g., by electronic means (such as a handheld transceiver, 
phone, or radio)) and make contact with the employees at least every 
two hours.
    (4) Hazard Alert. Prior to the work shift or upon determining the 
high heat trigger is met or exceeded, the employer must notify 
employees of the following:
    (i) The importance of drinking plenty of water;
    (ii) Employees' right to, at employees' election, take rest breaks 
if needed and the rest breaks required by paragraph (f)(2) of this 
section;
    (iii) How to seek help and the procedures to take in a heat 
emergency; and
    (iv) For mobile work sites, the location of break area(s) required 
by paragraph (e)(3) or (4) of this section and drinking water required 
by paragraph (e)(2) of this section.
    (5) Excessively high heat areas. The employer must place warning 
signs at indoor work areas with ambient temperatures that regularly 
exceed 120 [deg]F. The warning signs must be legible, visible, and 
understandable to employees entering the work areas.
    (g) Heat illness and emergency response and planning. (1) As part 
of their HIIPP, the employer must develop and implement a heat 
emergency response plan that includes:
    (i) A list of emergency phone numbers (e.g., 911, emergency 
services);
    (ii) A description of how employees can contact a supervisor and 
emergency medical services;
    (iii) Individual(s) designated to ensure that heat emergency 
procedures are invoked when appropriate;
    (iv) A description of how to transport employees to a place where 
they can be reached by an emergency medical provider;
    (v) Clear and precise directions to the work site, including the 
address of the work site, which can be provided to emergency 
dispatchers; and
    (vi) Procedures for responding to an employee experiencing signs 
and symptoms of heat-related illness, including heat emergency 
procedures for responding to an employee with suspected heat stroke.
    (2) If an employee is experiencing signs and symptoms of heat-
related illness, the employer must:
    (i) Relieve them from duty;
    (ii) Monitor them;
    (iii) Ensure they are not left alone;
    (iv) Offer them on-site first aid or medical services before ending 
monitoring; and
    (v) Provide them with the means to reduce their body temperature.
    (3) If an employee is experiencing signs and symptoms of a heat 
emergency, the employer must:
    (i) Take immediate actions to reduce the employee's body 
temperature before emergency medical services arrive;
    (ii) Contact emergency medical services immediately; and
    (iii) Perform activities described in paragraphs (g)(2)(i) through 
(iv) of this section.
    (h) Training--(1) Initial training. Prior to any work at or above 
the initial heat trigger, the employer must ensure that each employee 
receives training on, and understands, the following:
    (i) Heat stress hazards;
    (ii) Heat-related injuries and illnesses;
    (iii) Risk factors for heat-related injury or illness, including 
the contributions of physical exertion, clothing, personal protective 
equipment, a lack of acclimatization, and personal risk factors (e.g., 
age, health, alcohol consumption, and use of certain medications);
    (iv) Signs and symptoms of heat-related illness and which ones 
require immediate emergency action;

[[Page 71072]]

    (v) The importance of removing personal protective equipment that 
may impair cooling during rest breaks;
    (vi) Importance of taking rest breaks to prevent heat-related 
illness or injury, and that rest breaks are paid;
    (vii) Importance of drinking water to prevent heat-related illness 
or injury;
    (viii) The location of break areas;
    (ix) The location of employer-provided water;
    (x) The importance of employees reporting any signs and symptoms of 
heat-related illness they may experience, and those they observe in co-
workers;
    (xi) All policies and procedures that are applicable to the 
employee's duties, as indicated in the work site's HIIPP;
    (xii) The identity of the heat safety coordinator(s);
    (xiii) The requirements of this standard;
    (xiv) How the employee can access the work site's HIIPP; and
    (xv) Employees have a right to the protections required by this 
standard (e.g., rest breaks, water) and employers are prohibited from 
discharging or in any manner discriminating against any employee for 
exercising those rights.
    (xvi) If the employer is required by paragraph (f)(5) of this 
section to place warning signs for excessively high heat areas, they 
must train employees in the procedures to follow when working in these 
areas.
    (2) Supervisor training. The employer must ensure that each 
supervisor responsible for supervising employees performing any work at 
or above the initial heat trigger and each heat safety coordinator 
receives training on, and understands, both the topics outlined in 
paragraph (h)(1) of this section and the following:
    (i) The policies and procedures developed to comply with the 
applicable requirements of this standard, including the policies and 
procedures for monitoring heat conditions developed to comply with 
paragraphs (d)(1) and (d)(3)(ii) of this section; and
    (ii) The procedures the supervisor or heat safety coordinator must 
follow if an employee exhibits signs and symptoms of heat-related 
illness.
    (3) Annual refresher training. The employer must ensure that each 
employee receives annual training on, and understands, the subjects 
addressed in paragraph (h)(1) of this section. The employer must also 
ensure that each supervisor and heat safety coordinator additionally 
receives annual training on, and understands, the topics addressed in 
paragraph (h)(2) of this section. For employees who perform work 
outdoors, the employer must conduct the annual refresher training 
before or at the start of heat season.
    (4) Supplemental training. The employer must ensure that each 
employee promptly receives, and understands, additional training 
whenever:
    (i) Changes occur that affect the employee's exposure to heat at 
work (e.g., new job tasks);
    (ii) The employer changes the policies or procedures addressed in 
paragraph (h)(1)(xi) of this section;
    (iii) There is an indication that the employee has not retained the 
necessary understanding; or
    (iv) A heat-related injury or illness occurs at the work site that 
results in death, days away from work, medical treatment beyond first 
aid, or loss of consciousness.
    (5) Presentation. Training must be provided in a language and at a 
literacy level each employee, supervisor, and heat safety coordinator 
understands. The employer must provide employees with an opportunity 
for questions and answers about the training materials.
    (i) Recordkeeping. If the employer conducts on-site measurements at 
indoor work areas pursuant to paragraph (d)(3)(ii) of this section, 
they must have written or electronic records of those indoor work area 
measurements and retain those records for 6 months.
    (j) Requirements implemented at no cost to employees. The 
implementation of all requirements of this standard must be at no cost 
to employees, including paying employees their normal rate of pay when 
compliance requires employee time.
    (k) Dates--(1) Effective date. This standard is effective [60 days 
after date of publication of the final rule in the Federal Register].
    (2) Compliance date. Employers must comply with all requirements of 
this standard by [150 days after date of publication of the final rule 
in the Federal Register].
    (l) Severability. Each provision within this standard is separate 
and severable from the other provisions. If any provision of this 
standard is held to be invalid or unenforceable on its face, or as 
applied to any person, entity, or circumstance, or is stayed or 
enjoined, that provision shall be construed so as to continue to give 
the maximum effect to the provision permitted by law, unless such 
holding shall be one of utter invalidity or unenforceability, in which 
event the provision shall be severable from this standard and shall not 
affect the remainder of the standard.

PART 1915--OCCUPATIONAL SAFETY AND HEALTH STANDARDS FOR SHIPYARD 
EMPLOYMENT

0
5. The authority citation for part 1915 continues to read as follows:

    Authority: 33 U.S.C. 941; 29 U.S.C. 653, 655, 657; Secretary of 
Labor's Order No. 12-71 (36 FR 8754); 8-76 (41 FR 25059), 9-83 (48 
FR 35736), 1-90 (55 FR 9033), 6-96 (62 FR 111), 3-2000 (65 FR 
50017), 5-2002 (67 FR 65008), 5-2007 (72 FR 31160), 4-2010 (75 FR 
55355), 1-2012 (77 FR 3912), or 8-2020 (85 FR 58393); 29 CFR part 
1911; and 5 U.S.C. 553, as applicable.

Subpart F--General Working Conditions

0
6. Add Sec.  1915.95 to subpart F to read as follows:


Sec.  1915.95  Heat Injury and Illness Prevention.

    The requirements applicable to shipyard employment under this 
section are identical to the requirements set forth at 29 CFR 1910.148.

PART 1917--MARINE TERMINALS

0
7. The authority citation for part 1917 continues to read as follows:

    Authority:  33 U.S.C. 941; 29 U.S.C. 653, 655, 657; Secretary of 
Labor's Order No. 12-71 (36 FR 8754), 8-76 (41 FR 25059), 9-83 (48 
FR 35736), 1-90 (55 FR 9033), 6-96 (62 FR 111), 3-2000 (65 FR 
50017), 5-2002 (67 FR 65008), 5-2007 (72 FR 31160), 4-2010 (75 FR 
55355), 1-2012 (77 FR 3912), or 8-2020 (85 FR 58393), as applicable; 
and 29 CFR part 1911.

    Sections 1917.28 and 1917.31 also issued under 5 U.S.C. 553.
    Section 1917.29 also issued under 49 U.S.C. 1801-1819 and 5 
U.S.C. 553.

Subpart B--Marine Terminal Operations

0
8. Add Sec.  1917.32 to subpart B to read as follows:


Sec.  1917.32  Heat injury and illness prevention.

    The requirements applicable to marine terminals under this section 
are identical to the requirements set forth at 29 CFR 1910.148.

PART 1918--SAFETY AND HEALTH REGULATIONS FOR LONGSHORING

0
9. The authority citation for part 1918 continues to read as follows:

    Authority:  33 U.S.C. 941; 29 U.S.C. 653, 655, 657; Secretary of 
Labor's Order No. 12-71 (36 FR 8754), 8-76 (41 FR 25059), 9-83 (48 
FR 35736), 1-90 (55 FR 9033), 6-96 (62 FR 111), 3-2000 (65 FR 
50017), 5-2002 (67 FR 65008), 5-2007 (72 FR 31160), 4-2010 (75 FR 
55355), 1-2012 (77 FR 3912), or 8-2020 (85 FR 58393), as applicable; 
and 29 CFR 1911.

[[Page 71073]]

    Sections 1918.90 and 1918.110 also issued under 5 U.S.C. 553.
    Section 1918.100 also issued under 49 U.S.C. 5101 et seq. and 5 
U.S.C. 553.

0
10. Add subpart L to read as follows:

Subpart L--Occupational Health and Environmental Controls

Sec.
1918.111 through 1918.147 [Reserved]
1918.148 Heat injury and illness prevention.


Sec.  1918.148  Heat injury and illness prevention.

    The requirements applicable to longshoring operations and related 
employments under this section are identical to the requirements set 
forth at 29 CFR 1910.148.

PART 1926--SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION

0
11. The authority citation for part 1926 continues to read as follows:

    Authority: 40 U.S.C. 3704; 29 U.S.C. 653, 655, and 657; and 
Secretary of Labor's Order No. 12-71 (36 FR 8754), 8-76 (41 FR 
25059), 9-83 (48 FR 35736), 1-90 (55 FR 9033), 6-96 (62 FR 111), 3-
2000 (65 FR 50017), 5-2002 (67 FR 65008), 5-2007 (72 FR 31159), 4-
2010 (75 FR 55355), 1-2012 (77 FR 3912), or 8-2020 (85 FR 58393), as 
applicable; and 29 CFR part 1911, unless otherwise noted Sections 
1926.58, 1926.59, 1926.60, and 1926.65 also issued under 5 U.S.C. 
553 and 29 CFR part 1911.
    Section 1926.61 also issued under 49 U.S.C. 1801-1819 and 5 
U.S.C. 553.
    Section 1926.62 also issued under sec. 1031, Public Law 102-550, 
106 Stat. 3672 (42 U.S.C. 4853).
    Section 1926.65 also issued under sec. 126, Public Law 99-499, 
100 Stat. 1614 (reprinted at 29 U.S.C.A. 655 Note) and 5 U.S.C. 553.

Subpart D--Occupational Health and Environmental Controls

0
12. Add Sec.  1926.67 to subpart D to read as follows:


Sec.  1926.67  Heat injury and illness prevention.

    The requirements applicable to construction work under this section 
are identical to the requirements set forth at 29 CFR 1910.148.

PART 1928--OCCUPATIONAL SAFETY AND HEALTH STANDARDS FOR AGRICULTURE

0
11. The authority citation for part 1928 continues to read as follows:

    Authority: Sections 4, 6, and 8 of the Occupational Safety and 
Health Act of 1970 (29 U.S.C. 653, 655, 657); Secretary of Labor's 
Order No. 12-71 (36 FR 8754), 8-76 (41 FR 25059), 9-83 (48 FR 
35736), 1-90 (55 FR 9033), 6-96 (62 FR 111), 3-2000 (65 FR 50017), 
5-2002 (67 FR 65008), 4-2010 (75 FR 55355), or 8-2020 (85 FR 58393), 
as applicable; and 29 CFR 1911.
    Section 1928.21 also issued under 49 U.S.C. 1801-1819 and 5 
U.S.C. 553.

0
12. Amend Sec.  1928.21 by:
0
a. In paragraph (a)(8)(i), removing the word ``and'' at the end of the 
paragraph;
0
b. Revising paragraph (a)(8)(ii); and
0
c. Adding paragraph (a)(9).
    The revision and addition read as follows:


Sec.  1928.21  Applicable standards in 29 CFR part 1910.

    (a) * * *
    (8) * * *
    (ii) Agricultural establishments that maintain a temporary labor 
camp, regardless of how many employees are engaged on any given day in 
hand-labor operations in the field; and
    (9) Heat injury and illness prevention--Sec.  1910.148 of this 
chapter with respect to requirements applicable to agricultural 
operations.
* * * * *
[FR Doc. 2024-14824 Filed 8-29-24; 8:45 am]
 BILLING CODE 4510-26-P