Energy Conservation Program: Test Procedures for Compressors, 1052-1106 [2016-29427]

Agencies

• DEPARTMENT OF ENERGY

[Federal Register Volume 82, Number 2 (Wednesday, January 4, 2017)]
[Rules and Regulations]
[Pages 1052-1106]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2016-29427]



[[Page 1051]]

Vol. 82

Wednesday,

No. 2

January 4, 2017

Part IV





Department of Energy





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10 CFR Parts 429 and 431





Energy Conservation Program: Test Procedure for Compressors; Final Rule

Federal Register / Vol. 82 , No. 2 / Wednesday, January 4, 2017 / 
Rules and Regulations

[[Page 1052]]


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DEPARTMENT OF ENERGY

10 CFR Parts 429 and 431

[Docket No. EERE-2014-BT-TP-0054]
RIN 1904-AD43


Energy Conservation Program: Test Procedures for Compressors

AGENCY: Office of Energy Efficiency and Renewable Energy, Department of 
Energy.

ACTION: Final rule.

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SUMMARY: On May 5, 2016, the U.S. Department of Energy (DOE) published 
a notice of proposed rulemaking (NOPR) to establish new test procedures 
for certain varieties of compressors. That proposed rulemaking serves 
as the basis for the final rule. This final rule establishes 
definitions, materials incorporated by reference, sampling plans, 
representations requirements, enforcement provisions, and test 
procedures for certain varieties of compressors. Specifically, this 
final rule establishes full-load package isentropic efficiency as the 
applicable energy metric for certain fixed-speed compressors and part-
load package isentropic efficiency as the applicable energy metric for 
certain variable-speed compressors. Finally, this final rule 
incorporates by reference certain sections of the ISO Standard 
1217:2009(E), (ISO 1217:2009(E)), ``Displacement compressors--
Acceptance tests,'' as amended through Amendment 1:2016, as the basis 
for a test method for determining compressor efficiency. ISO 
1217:2009(E) includes a test method for measuring compressor inlet and 
discharge pressures, actual volume flow rate, electrical input power, 
package isentropic efficiency, and other compressor performance 
metrics. This final rule also adopts certain modifications and 
additions to ISO 1217:2009(E) to increase the specificity of certain 
testing methods established in ISO 1217:2009(E) and improve the 
repeatability of tested and measured values.

DATES: The effective date of this rule is February 3, 2017. The final 
rule changes will be mandatory for representations starting July 3, 
2017. The incorporation by reference of certain publications listed in 
the rule is approved by the Director of the Federal Register February 
3, 2017.

ADDRESSES: The docket, which includes Federal Register, public meeting 
attendee lists and transcripts, comments, and other supporting 
documents/materials, is available for review at www.regulations.gov. 
All documents in the docket are listed in the www.regulations.gov 
index. However, some documents listed in the index, such as those 
containing information that is exempt from public disclosure, may not 
be publicly available.
    A link to the docket Web page can be found at https://www1.eere.energy.gov/buildings/appliance_standards/product.aspx/productid/78. The docket Web page contains simple instructions on how 
to access all documents, including public comments, in the docket.

FOR FURTHER INFORMATION CONTACT: Mr. James Raba, U.S. Department of 
Energy, Office of Energy Efficiency and Renewable Energy, Building 
Technologies Office, EE-5B, 1000 Independence Avenue SW., Washington, 
DC 20585-0121. Telephone: (202) 586-8654. Email: 
ApplianceStandardsQuestions@ee.doe.gov.

SUPPLEMENTARY INFORMATION: This final rule incorporates by reference 
into 10 CFR part 431 the testing methods contained in the following 
commercial standards:
    ISO 1217:2009(E), ``Displacement compressors--Acceptance tests,'' 
July 1, 2009, sections 2, 3, and 4; sections 5.2, 5.3, 5.4, 5.6, 5.9; 
paragraphs 6.2(g), and 6.2(h) including Table 1; Annex C (excluding 
C.1.2, C.2.1, C.3, C.4.2.2, C.4.3.1, and C.4.5). ISO 1217:2009/
Amd.1:2016(E), Displacement compressors--Acceptance tests (Fourth 
edition); Amendment 1: ``Calculation of isentropic efficiency and 
relationship with specific energy,'' April 15, 2016, sections 3.5.1 and 
3.6.1; sections H.2 and H.3 of Annex H.
    Copies of ISO 1217:2009(E) and of ISO 1217:2009/Amendment 1:2016(E) 
may be purchased from ISO at Chemin de Blandonnet 8, CP 401, 1214 
Vernier, Geneva, Switzerland +41 22 749 01 11, or by going to 
www.iso.org.
    See section IV.N for additional information about ISO 1217:2009(E) 
and ISO 1217:2009/Amendment 1:2016(E).

Table of Contents

I. Authority and Background
    A. Authority
    B. Regulatory History for Compressors
II. Synopsis of the Final Rule
III. Discussion
    A. Definitions
    1. Definition of Covered Equipment
    2. Air Compressor
    3. Air Compressor Components
    4. Rotary and Reciprocating Compressors
    5. Brushless Electric Motor
    6. Compressor Motor Nominal Horsepower
    7. Volume Flow Rates
    8. Maximum Full-Flow Operating Pressure
    9. Lubricated Compressor
    B. Scope of Applicability of the Test Procedure
    1. Air Compressor Limitation
    2. Rotary and Reciprocating Compressors
    3. Driver Style
    4. Compressor Capacity
    5. Lubricant Presence
    6. Specialty-Purpose Compressors
    C. Metrics
    1. Package Isentropic Efficiency
    2. Package Specific Power
    3. Power Factor
    D. Incorporation by Reference of Industry Standard(s)
    1. ISO 1217:2009(E)/Amd.1:2016
    2. Comments Related to the incorporation of ISO 1217:2009(E)
    E. Test Method
    1. Measurement Equipment
    2. Test Conditions
    3. Equipment Configuration
    4. Data Collection and Analysis
    5. Determination of Full-Load and Part-Load Package Isentropic 
Efficiency
    6. Allowable Deviation from Specified Load Points
    7. Determination of Package Specific Power
    8. Determination of Pressure Ratio at Full-Load Operating 
Pressure
    9. Maximum Full-Flow Operating Pressure, Full-Load Operating 
Pressure, and Full-Load Actual Volume Flow Rate
    F. Definition of Basic Model
    G. Sampling Plan for Testing and Alternative Efficiency 
Determination Methods
    1. Sampling Plan and Representations
    2. Alternative Efficiency Determination Method
    H. Enforcement Provisions
    1. Sample Variability for Package Isentropic Efficiency
    2. Full-Load Operating Pressure and Actual Volume Flow Rate
IV. Procedural Issues and Regulatory Review
    A. Review Under Executive Order 12866
    B. Review Under the Regulatory Flexibility Act
    1. Description and Estimate of the Number of Small Entities 
Affected
    2. Discussion of Testing Burden and Comments
    C. Review Under the Paperwork Reduction Act of 1995
    D. Review Under the National Environmental Policy Act of 1969
    E. Review Under Executive Order 13132
    F. Review Under Executive Order 12988
    G. Review Under the Unfunded Mandates Reform Act of 1995
    H. Review Under the Treasury and General Government 
Appropriations Act, 1999
    I. Review Under Executive Order 12630
    J. Review Under Treasury and General Government Appropriations 
Act, 2001
    K. Review Under Executive Order 13211
    L. Review Under Section 32 of the Federal Energy Administration 
Act of 1974
    M. Congressional Notification
    N. Description of Materials Incorporated by Reference
V. Approval of the Office of the Secretary

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I. Authority and Background

A. Authority

    Title III of the Energy Policy and Conservation Act of 1975, as 
amended, (42 U.S.C. 6291, et seq.; ``EPCA'' or, ``the Act'') sets forth 
a variety of provisions designed to improve energy efficiency.\1\ Part 
C of Title III, which for editorial reasons was codified as Part A-1 
upon incorporation into the U.S. Code (42 U.S.C. 6311-6317), 
establishes the Energy Conservation Program for Certain Industrial 
Equipment. Under EPCA, DOE may include a type of industrial equipment, 
including compressors, as covered equipment if it determines that to do 
so is necessary to carry out the purposes of Part A-1. (42 U.S. 
6311(1)(L), 6311(2)(B)(i), and 6312(b)). The purpose of Part A-1 is to 
improve the efficiency of electric motors and pumps and certain other 
industrial equipment in order to conserve the energy resources of the 
Nation. (42 U.S.C. 6312(a))
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    \1\ All references to EPCA in this document refer to the statute 
as amended through the Energy Efficiency Improvement Act of 2015, 
Public Law 114-11 (Apr. 30, 2015).
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    Pursuant to EPCA, DOE's energy conservation program for covered 
equipment consists essentially of four parts: (1) Testing; (2) 
labeling; (3) Federal energy conservation standards; and (4) 
certification and enforcement procedures. Specifically, subject to 
certain criteria and conditions, EPCA requires DOE to develop test 
procedures to measure the energy efficiency, energy use, or estimated 
annual operating cost of each type of covered equipment. (42 U.S.C. 
6314(a)) Manufacturers of covered equipment must use the prescribed DOE 
test procedures: (1) As the basis for certifying to DOE that their 
equipment complies with the applicable energy conservation standards 
adopted under EPCA (42 U.S.C. 6295(s) and 6316(a)) and (2) when making 
representations to the public regarding the energy use or efficiency of 
those equipment. (42 U.S.C. 6314(d))

B. Regulatory History for Compressors

    Currently, no Federal energy conservation standards for compressors 
exist. Before today, no Federal test procedures for compressors 
existed.
    On December 31, 2012, DOE published a Proposed Determination of 
Coverage (2012 NOPD) proposing to determine that compressors qualify as 
covered equipment under part A-1 of Title III of EPCA, as amended (42 
U.S.C. 6311 et seq.). DOE proposed that coverage was necessary for the 
purposes of Part A-1 on the basis that (1) DOE may prescribe energy 
conservation standards only for covered equipment; and (2) energy 
conservation standards for compressors would improve the efficiency of 
such equipment more than would be likely to occur in the absence of 
standards.77 FR 76972 (Dec. 31, 2012). On February 7, 2013, DOE 
published a notice reopening the comment period on the 2012 NOPD. 78 FR 
8998.
    On November 15, 2016, DOE published a final rule, which determined 
that coverage for compressors is necessary to carry out the purposes of 
Part A-1 of Title III of EPCA (herein referred to as ``notice of final 
determination''). 81 FR 79991.
    On February 5, 2014, DOE published in the Federal Register a notice 
of public meeting, and provided a framework document that addressed 
potential standards and test procedures rulemakings for these products. 
79 FR 6839. DOE held a public meeting to discuss the framework document 
on April 1, 2014. At this meeting, DOE discussed and received comments 
on the framework document, which covered the analytical framework, 
models, and tools that DOE used to evaluate potential standards; and 
all other issues raised relevant to the development of energy 
conservation standards for the different categories of compressors. On 
March 18, 2014, DOE extended the comment period. 79 FR 15061.
    On May 5, 2016, DOE published a NOPR, to propose test procedures 
for certain compressors (``May 2016 test procedure NOPR'' or ``test 
procedure NOPR''). 87 FR 27220. The test procedure NOPR proposed 
establishing a new subpart T of title 10 of the Code of Federal 
Regulations, part 431 (10 CFR part 431), which would contain 
definitions, materials incorporated by reference, and test procedures 
for determining the energy efficiency of certain varieties of 
compressors. The test procedure NOPR would also amend title 10 CFR part 
429 to establish sampling plans, representations requirements, and 
enforcement provisions for certain compressors. On June 20, 2016, DOE 
held a public meeting to discuss the test procedure NOPR and receive 
comments from interested parties.
    Finally, in this final rule, DOE responds to comments received from 
interested parties in response to the proposals presented in the May 
2016 test procedure NOPR, either during the June 2016 NOPR public 
meeting or in subsequent written comments.\2\ In response to the May 
2016 test procedure NOPR, DOE received 17 written comments in addition 
to the verbal comments made by interested parties during the June 2016 
NOPR public meeting. The commenters included: the Appliance Standards 
Awareness Project (ASAP); Atlas Copco AB (Atlas Copco); CASTAIR; the 
Compressed Air & Gas Institute (CAGI); Compressed Air Systems; 
Ingersoll Rand; Jenny Products; Kaeser Compressors; the Northwest 
Energy Efficiency Alliance (NEEA); the Pacific Gas and Electric Company 
(PG&E), San Diego Gas and Electric (SDG&E), Southern California Edison 
(SCE), and Southern California Gas Company (SCGC), collectively 
referred to as the California Investor Owned Utilities (CA IOUs); the 
People's Republic of China (P. R. China); Scales Industrial 
Technologies; Sullair; Saylor-Beall Manufacturing Company and Sullivan-
Palatek, collectively referred to as Sullivan-Palatek. DOE identifies 
comments received in response to the May 2016 test procedure NOPR by 
the commenter, the number of document as listed in the docket 
maintained at www.regulations.gov (Docket No. EERE-2014-BT-TP-0054), 
and the page number of that document where the comment appears (for 
example: CAGI, No. 10 at p. 4). If a comment was made verbally during 
the NOPR public meeting, DOE also specifically identifies those as 
being located in the NOPR public meeting transcript (for example: CAGI, 
public meeting transcript, No. 16 at p. 100). This final rule also 
contains certain relevant comments that were submitted in response to 
the compressors energy conservation standards rulemaking and the 2012 
NOPD, but pertain to the topics discussed in the test procedure 
rulemaking. Those comments are identified with the appropriate docket 
numbers, EERE-2013-BT-STD-0040 and EERE-2012-BT-DET-0033, respectively.
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    \2\ DOE notes that certain comments pertaining to the definition 
of ``compressors'' were addressed in the November 2016 notice of 
final determination. 81 FR 79991, 79992-4 (Nov. 15, 2016).
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II. Synopsis of the Final Rule

    In this final rule, DOE amends subpart T of title 10 of the Code of 
Federal Regulations, part 431 (10 CFR part 431), which contains 
definitions, materials incorporated by reference, and test procedures 
for determining the energy efficiency of certain varieties of 
compressors.
    While the range of equipment included in DOE's definition of 
compressor is broad, the test procedures established by this rulemaking 
are limited to only a specific subset of

[[Page 1054]]

compressors. Specifically, this final rule applies only to a subset of 
rotary compressors, as defined in section III.B of this final rule. DOE 
intends this test procedure final rule to apply to similar equipment 
for which DOE is considering adopting energy conservation standards 
(Docket No. EERE-2014-BT-TP-0054). However, the scope of any energy 
conservation standards would be established in that rulemaking.
    This final rule establishes package isentropic efficiency as the 
applicable energy metric for compressors within the scope of the final 
rule. Package isentropic efficiency describes the ratio of the ideal 
isentropic power required for compression to the actual packaged 
compressor power input used for the same compression process. 
Specifically, this final rule establishes two varieties of package 
isentropic efficiency, depending on equipment configuration: (1) Full-
load package isentropic efficiency for certain fixed-speed compressors, 
and (2) part-load package isentropic efficiency for certain variable-
speed compressors. In this final rule, DOE concludes these metrics 
provide a representative measurement of the energy performance of the 
rated compressor under an average cycle of use.
    In this final rule, DOE establishes test methods to measure the 
inlet and discharge pressures, actual volume flow rate, and packaged 
compressor power input, as well as calculations of the theoretical 
power necessary for compression--all of which are required to calculate 
full- or part-load package isentropic efficiency. For reproducible and 
uniform measurement of these values, DOE incorporates by reference the 
test methods established in certain applicable sections of ISO 
1217:2009(E), ``Displacement compressors--Acceptance tests,'' as 
amended through ISO 1217:2009(E)/Amd.1:2016.\3\ Specifically, the test 
procedure codified by this final rule references the following parts of 
ISO 1217 as amended by Amendment 1:2016: sections 2, 3, and 4; 
subsections 5.2, 5.3, 5.4, 5.6, 5.9, 6.2(g), and 6.2(h); Annex C 
subsections C.1.1, C.2.2, C.2.3, C.2.4, C.4.1, C.4.2.1, C.4.2.3, 
C.4.3.2 and C.4.4; Annex H subsections H.2 and H.3; and Table 1 of 
subsection 6.2. See section III.D and section IV.N of this final rule 
for additional information about ISO 1217:2009(E) and ISO 1217:2009(E)/
Amd.1:2016. Members of the compressor industry developed ISO 
1217:2009(E), which contains methods for determining inlet and 
discharge pressures, actual volume flow rate, packaged compressor power 
input, and package isentropic efficiency for electrically driven 
packaged displacement compressors. DOE has reviewed the relevant 
sections of ISO 1217:2009(E), as amended, and has determined that ISO 
1217:2009(E), as amended, in conjunction with the additional 
clarifications and test methods and calculations established in this 
final rule (see section III.E), produces test results that reflect the 
energy efficiency of a compressor during a representative average use 
cycle. (42 U.S.C. 6314(a)(2)) DOE has also reviewed the burdens 
associated with conducting the test procedure established in this final 
rule, including ISO 1217:2009(E), as amended, and, based on the results 
of such analysis, has found that the test procedure would not be unduly 
burdensome to conduct. (42 U.S.C. 6314(a)(2)) DOE presents the analysis 
of the burdens associated with the test procedure in section IV.B.
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    \3\ ISO 1217:2009(E)/Amd.1:2016 is titled ``Calculation of 
isentropic efficiency and relationship with specific energy.''
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    In this final rule, DOE also establishes, in subpart B of part 429 
of title 10 of the Code of Federal Regulations (10 CFR part 429), 
sampling plan requirements, representations requirements, and 
enforcement provisions for the compressors within the scope of this 
final rule. The sampling plan requirements established in this final 
rule are similar to other types of commercial equipment (e.g., pumps) 
and are appropriate for compressors based on the expected range of 
measurement uncertainty and manufacturing tolerances for this 
equipment. The sampling plan is intended to give DOE reasonable 
assurance that any individual unit distributed in commerce is at least 
as efficient as its basic model rating. The representations 
requirements established in this final rule specify the energy 
consumption or energy efficiency representations that, in addition to 
the regulated metric (part- or full-load package isentropic 
efficiency), may be made by compressor manufacturers, distributors, 
retailers, or private labelers. DOE notes that any representations of 
the energy efficiency or energy use of compressors to which an adopted 
test procedure applies must be made based on the adopted compressor 
test procedure beginning 180 days after the publication date of any 
test procedure final rule establishing such procedures. (42 U.S.C. 
6314(d)) Finally, the enforcement provisions established in this final 
rule govern the process DOE follows when performing its own assessment 
of basic model compliance with any future energy conservation 
standards.

III. Discussion

A. Definitions

1. Definition of Covered Equipment
    Although EPCA lists compressors as a type of industrial equipment, 
the term is not defined. (42 U.S.C. 6311(2)(B)(i)) In the May 5, 2016 
test procedure NOPR, DOE proposed to define a ``compressor'' as a 
machine or apparatus that converts different types of energy into the 
potential energy of gas pressure for displacement and compression of 
gaseous media to any higher pressure values above atmospheric pressure 
and has a pressure ratio \4\ greater than 1.3. 81 FR 27220, 27223-
27224. Further, DOE noted that with its proposal of a pressure ratio of 
greater than 1.3, it intended to align the minimum pressure ratio for 
compressors with the maximum ratio proposed in the fans and blowers 
rule and to create a continuous spectrum of coverage between the two 
equipment types. Ibid.
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    \4\ For the final rule, the term ``pressure ratio'' has been 
revised to ``pressure ratio at full-load operating pressure,'' as 
explained later in this section.
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    To determine objectively and unambiguously whether equipment meets 
the definition of compressor, in the test procedure NOPR, DOE also 
proposed to define the term ``pressure ratio'' as the ratio of 
discharge pressure to inlet pressure, as determined at full-load 
operating pressure. Such a definition enables DOE to establish 
quantitatively which compressors meet the pressure ratio requirement 
proposed in the definition of the term compressor. 81 FR 27220, 27224 
(May 5, 2016).
    In the notice of final determination, DOE addressed all comments 
related to the definition of compressor, and ultimately adopted the 
following definition:
    Compressor means a machine or apparatus that converts different 
types of energy into the potential energy of gas pressure for 
displacement and compression of gaseous media to any higher pressure 
values above atmospheric pressure and has a pressure ratio at full-load 
operating pressure greater than 1.3. 81 FR 79991, 79998 (Nov. 15, 
2016).
    DOE notes that in the notice of final determination, for the 
definition of compressor, the term pressure ratio (which was proposed 
in the TP NOPR), was replaced with the term ``pressure ratio at full 
load operating pressure.'' DOE stated that the definition of the new 
term, as well as methods of testing,

[[Page 1055]]

would be established in the test procedure final rule. 81 FR 79991, 
79995 (Nov. 15, 2016). In this final rule, DOE addresses all comments 
related to the definition of the term pressure ratio. CAGI did not 
provide any direct comments, but commented that it was in agreement 
with DOE's proposal for items on which it did not directly comment. 
(CAGI, No. 0010, p. 3) Ingersoll Rand, Sullair, and Sullivan-Palatek 
supported CAGI's comments. (Ingersoll Rand, No. 0011 at p. 1; Sullair, 
No. 0006 at p. 1; Sullivan-Palatek, No. 0007 at p. 1)
    Jenny Products and Scales Industrial Technologies commented that 
they would prefer to use the more common term, ``compression ratio,'' 
in place of pressure ratio. Scales Industrial Technologies also 
indicated that DOE's proposed definition of pressure ratio was not 
sufficiently clear, and could be interpreted in multiple ways. (Scales 
Industrial Technologies, No. 0013, at p. 1; Jenny Products, No. 0020 at 
p. 2)
    In response to Scales Industrial Technologies' concerns about 
clarity, in this final rule, DOE is clarifying its NOPR proposal and 
modifying the term pressure ratio to pressure ratio at full-load 
operating pressure. This clarification better aligns the name of this 
metric with its definition, which states, as proposed, that pressure 
ratio means the ratio of discharge pressure to inlet pressure, 
determined at full-load operating pressure in accordance with the test 
procedures prescribed in Sec.  431.344. 81 FR 27220, 27224 (May 5, 
2016). DOE is making this clarification because it understands that the 
ratio between the inlet pressure and the discharge pressure, measured 
at the discharge pipe, can vary based on the pressure of the system 
that the compressor is supplying. As a result, DOE concludes that the 
use of the general term pressure ratio to describe a pressure ratio at 
a specific load point (i.e., full-load operating pressure), is not 
appropriate. Additionally, based on the general support of CAGI, 
Sullivan-Palatek, Ingersoll Rand, and Sullair, and the above 
clarification to the term pressure ratio, DOE concludes that the use of 
the term pressure ratio at full-load operating pressure is sufficiently 
clear, and DOE does not adopt the term compression ratio in its place.
    Ultimately, for the reasons discussed in this section and 
established in the test procedure NOPR, DOE is adopting the following 
definition for pressure ratio at full-load operating pressure. Beyond 
the previously discussed terminology change from pressure ratio to 
pressure ratio at full-load operating pressure, this definition is 
unchanged from the test procedure NOPR proposal.
    Pressure ratio at full-load operating pressure means the ratio of 
discharge pressure to inlet pressure, determined at full-load operating 
pressure in accordance with the test procedures prescribed in Sec.  
431.344.
2. Air Compressor
    In the test procedure NOPR, DOE proposed to define the term ``air 
compressor'' as a compressor designed to compress air that has an inlet 
open to the atmosphere or other source of air, and is made up of a 
compression element (bare compressor), driver(s), mechanical equipment 
to drive the compressor element, and any ancillary equipment. 81 FR 
27220, 27226 (May 5, 2016).
    In response to the proposed definitions, DOE received comment from 
CAGI indicating its support of the definitions as proposed for the test 
procedure. (CAGI, Public Meeting Transcript, No. 0016 at p. 20) 
Sullivan-Palatek, Ingersoll Rand, and Sullair supported CAGI's 
comments. (Sullivan-Palatek, No. 0007 at p. 1; Ingersoll Rand, No. 0011 
at p. 1; Sullair, No. 0006 at p. 1)
    Consequently, for the reasons established in the test procedure 
NOPR, DOE is adopting the definition for air compressor as proposed in 
the test procedure NOPR.
3. Air Compressor Components
a. Bare Compressor, Driver, and Mechanical Equipment
    In the test procedure NOPR, DOE proposed to define ``bare 
compressor'' \5\ as the compression element and auxiliary devices 
(e.g., inlet and outlet valves, seals, lubrication system, and gas flow 
paths) required for performing the gas compression process. The 
definition does not include the driver; speed-adjusting gear(s); gas 
processing apparatuses and piping; or compressor equipment packaging 
and mounting facilities and enclosures. 81 FR 27220, 27227 (May 5, 
2016).
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    \5\ The compressors industry frequently uses the term ``airend'' 
or ``air end'' to refer to the bare compressor. DOE uses ``bare 
compressor'' in the regulatory text of this rule, and, for the 
purposes of this rulemaking, it considers the terms to be 
synonymous.
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    Further, in the test procedure NOPR, DOE proposed to define 
``driver'' and ``mechanical equipment'' as the machine providing 
mechanical input to drive a bare compressor directly or through the use 
of mechanical equipment, and any component of an air compressor that 
transfers energy from the driver to the bare compressor, respectively. 
81 FR 27220, 27227 (May 5, 2016).
    In response to the proposed definitions, CAGI did not provide any 
direct comments, but CAGI commented that it was in agreement with DOE's 
proposal for items on which it did not directly comment. (CAGI, No. 
0010, p. 3) Ingersoll Rand, Sullair, and Sullivan-Palatek supported 
CAGI's comments. (Ingersoll Rand, No. 0011 at p. 1; Sullair, No. 0006 
at p. 1; Sullivan-Palatek, No. 0007 at p. 1) Scales Industrial 
Technologies commented that the `bare' compressor often includes speed-
increasing gears. (Scales Industrial Technologies, no. 0013 at p. 2) In 
response, DOE clarifies that while the definition of bare compressor 
does not include mention of gears, the definition of mechanical 
equipment does include mention of gears. Moreover, the definition of 
air compressor, which is the overarching term dictating the scope of 
applicability of equipment in this final rule, includes mechanical 
equipment. Consequently, for the reasons established in the test 
procedure NOPR, DOE is adopting the definitions for bare compressor, 
driver, and mechanical equipment as proposed in the test procedure 
NOPR.
b. Ancillary Equipment
    In the test procedure NOPR, the proposed definition of air 
compressor included the term ``ancillary equipment.'' DOE proposed to 
define ancillary equipment as any equipment distributed in commerce 
with an air compressor that is not a bare compressor, driver, or 
mechanical equipment. 81 FR 27220, 27227 (May 5, 2016). Ancillary 
equipment would be considered to be part of a given air compressor 
model regardless of whether the ancillary equipment is physically 
attached to the bare compressor, driver, or mechanical equipment at the 
time when the air compressor is distributed in commerce. Ibid. DOE also 
requested comment on if a list of ancillary equipment was more 
appropriate than the definition. Ibid.
    Many commenters suggested that the definition of ancillary 
equipment proposed in the test procedure NOPR lacked specificity. 
Scales Industrial Technologies, Kaeser Compressors, and Jenny Products 
commented that standard, but not application-specific or optional, 
ancillary equipment should be used as required for the safe operation 
of the bare compressor. Kaeser Compressors noted that the metric of 
isentropic efficiency is expressed relative to the theoretical power 
required to compress air, and thus the specified test configuration 
should

[[Page 1056]]

logically reflect the equipment required to compress air, without the 
effect of any additional components. Scales Industrial Technologies 
stated that standard compressors should not include accessories beyond 
an aftercooler, a moisture separator, and an automatic drain cap. 
(Jenny Products, No. 0020 at pp. 2-3; Scales Industrial Technologies, 
No. 0013 at p. 2; Kaeser Compressors, Public Meeting Transcript, No. 
0016 at pp. 31, 37)
    ASAP commented that the definition of ancillary equipment should be 
clear and include equipment that is normally included with a majority 
of applications. (ASAP, Public Meeting Transcript, No. 0016 at pp. 25, 
30) Similarly, Compressed Air Systems commented that the list of 
ancillary equipment should be defined, noting that safety equipment 
should be included as part of the list to ensure safe operation of 
compressors. (Compressed Air Systems, No. 0008 at p. 1) Atlas Copco 
agreed that the proposed definition of ancillary equipment was not 
appropriate, and commented that DOE should consider a definition 
similar to the one used in the EU Lot 31 draft standard. Atlas Copco 
argues that following the EU Lot 31 standard would allow for accurate 
comparisons of the energy consumption of similar basic models of 
compressors and would not penalize manufacturers who efficiently 
integrate optional ancillary equipment into the compressor design. 
(Atlas Copco, No. 0009 at pp. 10-11; Atlas Copco, Public Meeting 
Transcript, No. 0016 at pp. 34-35) CAGI and Ingersoll Rand also 
supported a clearer definition and suggested the use of a list of 
equipment to define the term ancillary equipment, with Ingersoll Rand 
further commenting that optional equipment such as ancillary air 
treatment equipment should be excluded from the test procedures. (CAGI, 
Public Meeting Transcript, No. 0016 at pp. 27-28; Ingersoll Rand, 
Public Meeting Transcript, No. 0016 at pp. 29, 33) CAGI provided a list 
that is slightly modified from the one used by the EU Lot 31 draft 
standard; this list is reproduced in Table III.1. (CAGI, No. 0010 at p. 
3; CAGI, Public Meeting Transcript, No. 0016 at p. 37) CAGI stated that 
this list is limited to equipment that is required for safety or basic 
compressor functionality. (CAGI, No. 0010 at p. 3) CAGI further 
indicated that all other equipment is optional and should not be 
included for testing. (CAGI, No. 0010 at pp. 4-5; CAGI, Public Meeting 
Transcript, No. 0016 at p. 37)

               Table III.1--CAGI-Suggested List of Ancillary Equipment To Be Included for Testing
----------------------------------------------------------------------------------------------------------------
Configuration of basic compressor            Fixed-speed rotary                    Variable-speed rotary
----------------------------------------------------------------------------------------------------------------
Speed............................  Fixed.................................  Variable.
Cooling..........................  Air-cooled/Water-cooled...............  Air-cooled/Water-cooled.
Electric motor (driver)..........  Yes...................................  Yes.
Cooling fan(s) and motors........  Yes...................................  Yes.
Compression element (bare          Yes...................................  Yes.
 compressor).
Transmission (belt, gear,          Yes (if applicable) **................  Yes (if applicable) **.
 coupling, etc.) (mechanical
 equipment).
Inlet filter.....................  Yes...................................  Yes.
Inlet valve......................  Yes...................................  Yes.
Minimum pressure check valve/      Yes...................................  Yes.
 backflow check valve.
Oil separator....................  Yes...................................  Yes.
Air piping.......................  Yes...................................  Yes.
Oil piping.......................  Yes...................................  Yes.
Oil pump.........................  Yes (if applicable) **................  Yes (if applicable) **.
Oil filter.......................  Yes...................................  Yes.
Oil cooler.......................  Yes...................................  Yes.
Thermostatic valve...............  Yes...................................  Yes.
Electrical switchgear............  Yes *.................................  No *.
Frequency converter..............  No *..................................  Yes *.
Compressed air cooler(s).........  Yes...................................  Yes.
Compressor control device          Yes...................................  Yes.
 (pressure switch, pressure
 transducer, electronic or
 electrical controls, etc.).
Protective devices...............  Yes...................................  Yes.
Moisture separator and drain.....  Yes...................................  Yes.
----------------------------------------------------------------------------------------------------------------
* Electrical switchgear and frequency converter only concern the main electric drive motor, other motors (e.g.,
  fans, pumps) may still be driven by a variable-speed drive and/or include electrical switchgear and/or
  frequency converter.
** The term ``if applicable'' means that if the functionality of the basic package is achieved without the
  component, then it does not need to be included.

    Sullair and Sullivan-Palatek expressed support of the CAGI position 
and the list defined by CAGI in Table III.1; Sullivan-Palatek further 
argued that a consistent list of installed equipment, rather than what 
is included in commerce, is important such that compressors can be 
compared to each other consistently. (Sullair, No. 0006 at p. 7; 
Sullivan-Palatek, No. 0007 at pp. 3, 4; Sullivan-Palatek, Public 
Meeting Transcript, No. 0016 at p. 28) Ingersoll Rand expanded on the 
importance of using a list to define ancillary equipment, noting that 
manufacturers independently have been self-declaring a basic compressor 
when representing unit efficiency, which in turn has been used by DOE 
to analyze standards for compressors. (Ingersoll Rand, Public Meeting 
Transcript, No. 0016 at p. 36) Sullair supported comments from Kaeser 
Compressors and CAGI, elaborating that items not included in the list 
of ancillary equipment developed by CAGI are customer-driven additional 
equipment and out of the control of a manufacturer. (Sullair, Public 
Meeting Transcript, No. 0016 at pp. 33-34) NEEA commented that a filter 
should be included as part of the definition of ancillary equipment, 
but would consider dropping the suggestion of adding a filter to the 
list of ancillary equipment if the draft EU compressor standard also 
does not require a filter. (NEEA, Public Meeting Transcript, No. 0016 
at p. 35)
    Further, CAGI commented that if a unit is offered for sale without 
a piece of equipment on its recommended list, the manufacturer must 
provide an appropriate component, and the selection and responsibility 
of providing and installing this component for testing

[[Page 1057]]

shall be the responsibility of the manufacturer. (CAGI, No. 0010 at p. 
5)
    In response to these comments, DOE agrees with CAGI and other 
commenters that DOE should develop a list of equipment that must be 
present for testing. Further, DOE generally agrees with the list 
provided by CAGI. However, instead of including a specific list as part 
of the definition of ancillary equipment, DOE is maintaining a broad 
definition of ancillary equipment and adopting a list of equipment that 
must be present for testing in the equipment configuration section of 
the test method (see section III.E.3 for complete details). This 
approach helps avoid loopholes, as it ensures that compressors 
distributed in commerce with additional equipment outside this list are 
still within the scope of the test procedure, but such equipment is 
tested only with the equipment on the list. Further, this approach 
helps ensure that all compressors within the scope of this rulemaking 
are rated fairly and equitably with a consistent set of equipment 
present, addressing the concerns of Sullivan-Palatek. DOE concludes 
that this approach is consistent with CAGI's comments, which made clear 
that its list was the required subset of all potential equipment that 
it believed should be present for testing. As a result, DOE is adopting 
the definition of ancillary equipment proposed in the test procedure 
NOPR. Please see section III.E.3 for a complete discussion of specific 
equipment that is required for testing.
4. Rotary and Reciprocating Compressors
    In the test procedure NOPR, DOE proposed the following definitions 
for rotary and reciprocating compressors:
    Rotary compressor means a positive displacement compressor in which 
gas admission and diminution of its successive volumes or its forced 
discharge are performed cyclically by rotation of one or several rotors 
in a compressor casing. 81 FR 27220, 27228 (May 5, 2016).
    Reciprocating compressor means a positive displacement compressor 
in which gas admission and diminution of its successive volumes are 
performed cyclically by straight-line alternating movements of a moving 
member(s) in a compression chamber(s). 81 FR 27220, 27228 (May 5, 
2016).
    To support these definitions, DOE also proposed ``positive-
displacement compressor'' to mean a compressor in which the admission 
and diminution of successive volumes of the gaseous medium are 
performed periodically by forced expansion and diminution of a closed 
space(s) in a working chamber(s) by means of displacement of a moving 
member(s) or by displacement and forced discharge of the gaseous medium 
into the high-pressure area.
    In response to the proposed definitions, CAGI agreed with the 
proposed compressor definitions, but stated that defining ``rotor'' 
would characterize the equipment more accurately, and suggested the 
following definition: A compression element that rotates continually in 
a single direction [around] a single shaft or axis. (CAGI, No. 0010 at 
p. 5) CAGI further commented that, beyond rotary screw compressors, 
other types of rotary compressors, such as rotary vane and scroll, 
would be covered under the definition. (CAGI, Public Meeting 
Transcript, No. 0016 at p. 22) However, CAGI did not specifically 
recommend whether these other rotary compressors should, or should not, 
be included within the scope of the test procedure. Sullair added that 
DOE should clarify which compressor technologies, such as scroll and 
vane, met the proposed definition. (Sullair, Public Meeting Transcript, 
No. 0016 at p. 23) Sullivan-Palatek, Ingersoll Rand, and Sullair 
supported CAGI's comments. (Ingersoll Rand, No. 0011 at p. 1; Sullivan-
Palatek, No. 0007 at p. 1; Sullair, No. 0006 at p. 1)
    DOE agrees with CAGI and Sullair's comments that a definition of 
rotor and examples of rotary compressors would improve the accuracy of 
the rotary compressor definition. Further, DOE agrees with CAGI's 
recommended definition and finds it to be technically accurate. For 
this reason, in this final rule, DOE is adopting the definition of 
rotor, as recommended by CAGI. In response to Sullair's request for 
examples, DOE notes that rotary compressors include, but are not 
limited to, rotary screw, sliding vane, rotary lobe, and liquid ring. 
However, DOE does not believe that scroll compressors meet the 
definition of rotary compressors, as scroll compressors nutate (or 
orbit) rather than rotate continually in a single direction around a 
single shaft or axis.
    Beyond these clarifications, DOE is making no changes to the 
remaining definitions discussed in this subsection, and for the reasons 
established in the test procedure NOPR, DOE is adopting in this final 
rule the definitions for rotary compressor, reciprocating compressor, 
and positive-displacement compressor, as proposed in the test procedure 
NOPR.
5. Brushless Electric Motor
    In the test procedure NOPR, DOE proposed to define a ``brushless 
electric motor'' as a machine that converts electrical power into 
rotational mechanical power without use of sliding electrical contacts. 
Further, DOE considered brushless motors to include, but not be limited 
to, what are commonly known as induction, brushless direct current, 
permanent magnet, electrically commutated, and reluctance motors. 81 FR 
27220, 27229 (May 5, 2016).
    In response to the proposed definitions, CAGI did not provide any 
direct comments, but commented that it was in agreement with DOE's 
proposal for items on which it did not directly comment. (CAGI, No. 
0010, p. 3) Ingersoll Rand, Sullair, and Sullivan-Palatek supported 
CAGI's comments. (Ingersoll Rand, No. 0011 at p. 1; Sullair, No. 0006 
at p. 1; Sullivan-Palatek, No. 0007 at p. 1) Consequently, for the 
reasons established in the test procedure NOPR, DOE is adopting the 
definition for brushless motor as proposed in the test procedure NOPR.
6. Compressor Motor Nominal Horsepower
    In the test procedure NOPR, DOE proposed ``compressor motor nominal 
horsepower'' (``hp'') to mean the motor horsepower of the electric 
motor with which the rated air compressor is distributed in commerce, 
as determined in accordance with the applicable procedures in subparts 
B and X of 10 CFR part 431. 81 FR 27220, 27229 (May 5, 2016).
    In response to the proposed definitions, CAGI did not provide any 
direct comments, but commented that it was in agreement with DOE's 
proposal for items on which it did not directly comment. (CAGI, No. 
0010, p. 3) Ingersoll Rand, Sullair, and Sullivan-Palatek supported 
CAGI's comments. (Ingersoll Rand, No. 0011 at p. 1; Sullair, No. 0006 
at p. 1; Sullivan-Palatek, No. 0007 at p. 1) Consequently, for the 
reasons established in the test procedure NOPR, DOE is adopting in this 
final rule the definition for compressor motor nominal horsepower as 
proposed in the test procedure NOPR.
7. Volume Flow Rates
    In the test procedure NOPR, DOE proposed that ``actual volume flow 
rate'' mean the volume flow rate of air, compressed and delivered at 
the standard discharge point, referred to conditions of total 
temperature, total pressure, and composition prevailing at the standard 
inlet point, and as

[[Page 1058]]

determined in accordance with the test procedures proposed for 10 CFR 
431.344. Further, DOE also proposed that full-load actual volume flow 
rate mean the actual volume flow rate of the compressor at the full-
load operating pressure. 81 FR 27220, 27231 (May 5, 2016).
    In response to the proposed definitions, CAGI did not provide any 
direct comments, but CAGI commented that it was in agreement with DOE's 
proposal for items on which it did not directly comment. (CAGI, No. 
0010, p. 3) Ingersoll Rand, Sullair, and Sullivan-Palatek supported 
CAGI's comments. (Ingersoll Rand, No. 0011 at p. 1; Sullair, No. 0006 
at p. 1; Sullivan-Palatek, No. 0007 at p. 1) Consequently, for the 
reasons established in the test procedure NOPR, DOE is adopting in this 
final rule the definitions for actual volume flow rate and full-load 
actual volume flow rate as proposed in the test procedure NOPR.
8. Maximum Full-Flow Operating Pressure
    In the test procedure NOPR, DOE proposed ``maximum full-flow 
operating pressure'' to mean the maximum discharge pressure at which 
the compressor is capable of operating, as determined in accordance 
with the test procedures proposed for 10 CFR 431.344.\6\ 81 FR 27220, 
27231 (May 5, 2016).
---------------------------------------------------------------------------

    \6\ A discussion of the test procedure to determine the maximum 
full-flow operating pressure can be found in section III.E.9.
---------------------------------------------------------------------------

    In response to the proposed definition, CAGI did not provide any 
direct comments, but CAGI commented that it was in agreement with DOE's 
proposal for items on which it did not directly comment. (CAGI, No. 
0010, p. 3) Ingersoll Rand, Sullair, and Sullivan-Palatek supported 
CAGI's comments. (Ingersoll Rand, No. 0011 at p. 1; Sullair, No. 0006 
at p. 1; Sullivan-Palatek, No. 0007 at p. 1) Consequently, for the 
reasons established in the test procedure NOPR, in this final rule DOE 
is adopting the definition for maximum full-flow operating pressure 
proposed in the test procedure NOPR.
9. Lubricated Compressor
    In the energy conservation standards NOPR, DOE proposed 
``lubricated compressor'' to mean a compressor that introduces an 
auxiliary substance into the compression chamber during compression. 81 
FR 31680, 31698 (May 19, 2016). Analogously, DOE proposed ``lubricant-
free compressor'' to mean a compressor that does not introduce any 
auxiliary substance into the compression chamber at any time during 
operation. 81 FR 31680, 31698 (May 19, 2016). To support these 
definitions, DOE proposed ``auxiliary substance'' to mean any substance 
deliberately introduced into a compression process to aid in 
compression of a gas by any of the following: Lubricating, sealing 
mechanical clearances, and/or absorbing heat. 81 FR 31680, 31698 (May 
19, 2016).
    In the energy conservation standards NOPR, DOE discussed ISO 
Standard 8573-1:2010, ``Compressed air--Part 1: Contaminants and purity 
classes,'' (hereinafter referred to as ``ISO 8573-1:2010'') which is 
used by industry to measure and describe the purity of air.\7\ DOE did 
not propose to use ISO 8573-1:2010, but requested comment on the 
suitability of using this standard to characterize compressors based on 
the presence of lubricant in the compression chamber. 81 FR 31680, 
31698 (May 19, 2016).
---------------------------------------------------------------------------

    \7\ Available at: https://www.iso.org/iso/catalogue_detail.htm?csnumber=46418.
---------------------------------------------------------------------------

    In response, CAGI commented that ISO 8573-1:2010 is a standard for 
measuring the quality of air and, as such, is not suitable for 
determining the presence of lubricant in the compression chamber. 
(EERE-2013-BT-STD-0040, CAGI, No. 0052 at p. 10) Ingersoll Rand, Mattei 
Compressors, Sullair, and Sullivan-Palatek commented in support of 
CAGI's recommendations. (Ingersoll Rand, No. 0055 at p. 1; Mattei 
Compressors, No. 0063 at p. 2; Sullair, No. 0056 at p. 1; Sullivan-
Palatek, No. 0051 at p. 1) Beyond this commentary, CAGI provided no 
comments or recommendations regarding the definitions of lubricated 
compressor and lubricant-free compressor, as proposed in the energy 
conservation standard NOPR. Kaeser Compressors commented that ISO 8573-
1:2010 is not suitable for defining a lubricated compressor and agreed 
with DOE's approach in the NOPR regarding the definition of an 
auxiliary substance without reference to ISO 8573-1:2010. (Kaeser 
Compressors, Public Meeting Transcript, No. 0044 at p. 21)
    DOE agrees with the comments made by CAGI, Ingersoll Rand, Mattei 
Compressors, Sullair, Sullivan-Palatek, and Kaeser Compressors, and 
does not use ISO 8573-1:2010 in the definition of lubricated compressor 
in this final rule. Additionally, due to the reasons established in the 
test procedure NOPR, and due to support from Kaeser Compressors, in 
this final rule DOE is adopting the definitions for lubricated 
compressor, lubricant-free compressor, and auxiliary substance as 
proposed in the energy conservation standards NOPR.

B. Scope of Applicability of the Test Procedure

    In the test procedure NOPR, DOE proposed to limit the scope of 
applicability of the compressors test procedures to compressors that 
meet the following criteria:
     Are air compressors;
     are rotary or reciprocating compressors;
     are driven by a brushless electric motor;
     are distributed in commerce with a compressor motor 
nominal horsepower greater than or equal to 1 hp and less than or equal 
to 500 hp; and
     operate at a full-load operating pressure of greater than 
or equal to 31 pounds per square inch, gauge (``psig'') and less than 
or equal to 225 psig;
    The proposed test procedure NOPR scope directly aligned with the 
scope of compressor equipment that DOE analyzed for the May 5, 2016 
energy conservation standards NOPR for compressors. 81 FR 27220, 27224-
5. Similarly, in this final rule, DOE intends to directly align the 
scope of the compressors test procedures with the scope of the 
forthcoming energy conservation standards final rule. However, while 
DOE intends the scope of the test procedures adopted in this final rule 
to be consistent with that of any energy conservation standard that may 
eventually be established for compressors, DOE notes that the scope of 
any energy conservation standards will be established as part of a 
separate rulemaking.
    As such, based on comments received in response to both the test 
procedure and energy conservation standards NOPR, the scope of this 
test procedure final rule is limited to compressors that meet the 
following criteria:
     Are air compressors;
     are rotary compressors;
     are not liquid ring compressors;
     are driven by a brushless electric motor;
     are lubricated compressors;
     have a full-load operating pressure of 75-200 psig;
     are not designed and tested to the requirements of The 
American Petroleum Institute standard 619, ``Rotary-Type Positive-
Displacement Compressors for Petroleum, Petrochemical, and Natural Gas 
Industries;'' and
     have a capacity that is either:
    o 10-200 compressor motor nominal horsepower (hp), or

[[Page 1059]]

    o 35-1,250 full-load actual volume flow rate (cfm).
    Detailed discussion of each of the scope limitations, associated 
benefits and burdens, and interested party comments, are in the 
subsections that follow.
1. Air Compressor Limitation
    In the test procedure NOPR, DOE proposed to limit the scope of the 
compressors test procedure to air compressors, as defined in section 
III.A.2.
    In response to the 2012 NOPD, Ingersoll Rand commented that losses 
in efficiency are often attributable to system-level losses as opposed 
to package-level losses. Ingersoll Rand stated that, therefore, little 
benefit would be achieved by regulating the compressor package alone 
without providing guidance for the overall compressed air system. 
(Docket No. EERE-2012-BT-DET-0033, Ingersoll Rand, No. 0004 at p. 2) 
CAGI argued that estimating compressor energy consumption, alone, is 
difficult because it is often operated in an ensemble of accompanying 
equipment, including other compressors. (Docket No. EERE-2012-BT-DET-
0033, CAGI, No. 0003, at pp. 5-6)
    In response to the more recent 2016 test procedure NOPR, CAGI and 
Ingersoll Rand provided updated positions on the subject, and agreed 
with DOE's proposal for items on which they did not directly comment. 
(CAGI, No. 0010 at p. 3; Ingersoll Rand, No. 0011 at p. 1) Sullivan-
Palatek and Sullair supported CAGI's comments. (Sullivan-Palatek, No. 
0007 at p. 1; Sullair, No. 0006 at p. 1) CASTAIR disagreed with the 
notion of efficiency standards for air compressors, arguing that DOE 
should only regulate the manufacturers of bare compressors, as air 
compressor assemblers have very little control over efficiency. 
(CASTAIR, No. 0018 at p. 1)
    In response to CASTAIR, the efficiency of an air compressor is not 
solely a function of the bare compressor. As DOE discussed in the test 
procedure NOPR, opportunities exist to select high efficiency motors, 
drives (if applicable), mechanical equipment, and ancillary equipment 
that affect efficiency. Further, proper sizing and integration of this 
equipment also influences efficiency. In the test procedure NOPR, DOE 
specifically evaluated the option of regulating at the bare compressor 
and packaged compressor level. For the reasons just mentioned, DOE 
concluded that regulating a bare compressor would result in 
significantly lower energy savings opportunity compared to the packaged 
compressors. Further, DOE concluded that determining the energy 
performance of the bare compressor alone would not be representative of 
the energy consumption of the equipment under typical use conditions. 
81 FR 27220, 27225 (May 5, 2016).
    Based on these reasons and the support of many interested parties, 
DOE maintains its NOPR proposal, and is limiting the scope of the 
compressors test procedure final rule to air compressors as defined in 
section III.A.2 of this final rule.
2. Rotary and Reciprocating Compressors
    In the test procedure NOPR, DOE proposed to include only rotary and 
reciprocating compressors within the scope of the test procedure, and 
not to include dynamic compressors. 81 FR 27220, 27228 (May 5, 2016).
    In response to the test procedure NOPR, the CA IOUs supported the 
inclusion of reciprocating compressors in the scope of the test 
procedure and recommended that DOE require testing and performance data 
reporting for reciprocating compressors, noting that making their 
performance data publicly available would be helpful for future 
rulemakings and utility incentive programs. The CA IOUs recommended a 
phased approach for reciprocating compressors to reduce the burden on 
manufacturers, in which testing and reporting of performance data would 
be required over a long period of time. (CA IOUs, No. 0012 at p. 4)
    Sullair commented that any equipment covered by the test procedure 
and not the standard presents a significant burden to the manufacturer 
and a competitive advantage to competing unregulated technologies 
without a resulting improvement in unit efficiency. (Sullair, No. 0006 
at p. 3)
    DOE agrees with the CA IOUs that establishing test procedures and 
public reporting requirements for reciprocating compressors could be 
helpful in future rulemakings and utility incentive programs. However, 
in the energy conservation standards NOPR, DOE concluded that energy 
conservation standards for reciprocating compressors are not 
economically justified at this time; as such, DOE did not propose 
energy conservation standards for reciprocating compressors. 81 FR 
31680 (May 19, 2016). As discussed previously, and in agreement with 
Sullair's comments, DOE concludes that in the absence of existing or 
proposed energy conservation standards for reciprocating equipment, 
establishing a test procedure to measure performance of such equipment 
is not warranted at this time. Further, DOE concludes that the burdens 
associated with such a test procedure, as discussed by Sullair, 
outweigh any potential benefits at this time. Consequently, in this 
final rule, DOE is adopting test methods applicable only to certain 
rotary compressors and is not adopting any testing requirements for 
reciprocating compressors at this time.
    In response to the concurrent energy conservation standards 
rulemaking, ASAP, NEEA, NWPCC, CA IOUs, and Sullivan-Palatek suggested 
that DOE's consideration of reciprocating compressors as one, 
monolithic category may be inappropriate, as reciprocating compressors 
are built to a wide range of efficiencies, intended duty cycles, and 
configurations based on capacity. Further, Sullivan-Palatek suggested 
that a fraction of compressors in the reciprocating market are likely 
to be used in industrial settings and may be worth considering 
separately from the rest. (EERE-2013-BT-STD-0040, NEEA and NWPCC, No. 
0057 at pp. 1-2; Docket No. EERE-2013-BT-STD-0040, ASAP, Public Meeting 
Transcript, No. 0044 at pp. 151-152; Docket No. EERE-2013-BT-STD-0040, 
CA IOUs, No. 0059 at p. 3; Docket No. EERE-2013-BT-STD-0040, Sullivan-
Palatek, Public Meeting Transcript, No. 0044 at pp. 67-68, 84-85, 87, 
112-113, 114, 115-116) DOE acknowledges these suggestions and concludes 
that separately reassessing certain segments of the reciprocating 
marketing may lead DOE to a better informed assessment of the burdens 
and benefits of test procedures and energy conservation standards for 
reciprocating compressors. However, at this time, insufficient data 
exists to perform such a specific characterization of the reciprocating 
market, as noted by NEEA. (Docket No. EERE-2013-BT-STD-0040, NEEA, 
Public Meeting Transcript, No. 0044 at pp. 123-124) Consequently, DOE 
concludes the most suitable path forward is to explore the 
appropriateness of test procedures and energy conservation standards 
for reciprocating compressors in a future, separate rulemaking.
    As a point of clarification, DOE notes that compressors that 
combine more than one type of compression principle (e.g., rotary and 
reciprocating elements within a single compressor package) do not meet 
DOE's adopted definition of rotary compressor, and, therefore, are 
subject to the test procedures adopted in this final rule.
    As noted in section III.A.4, liquid ring compressors meet the 
definition of a rotary compressor. Specifically, ISO

[[Page 1060]]

1217:2009(E), as amended,\8\ defines ``liquid ring compressor'' as a 
machine with a rotating impeller with protruding blades eccentrically 
mounted in a stationary round housing or centrally mounted in a 
stationary elliptical housing.
---------------------------------------------------------------------------

    \8\ In this final rule, DOE is incorporating by reference parts 
of ISO 1217:2009(E) as amended by Amendment 1:2016. Amendment 1:2016 
did not introduce any changes in regards to this particular topic. 
For details on ISO 1217:2009(E) and Amendment 1:2016, see III.D and 
IV.N.
---------------------------------------------------------------------------

    In this final rule, DOE is explicitly excluding liquid ring 
compressors from the scope of applicability of this test procedure. 
Although liquid ring compressors are rotary compressors, they provide a 
unique utility for applications that require a durable compressor 
tolerant of dirty input air and ingested liquid. Due to this utility 
and construction, liquid ring compressors require test methods 
different from those proposed in the test procedure NOPR. Specifically, 
ISO 1217:2009(E), as amended,\9\ specifies that due to their 
configuration, liquid ring compressors should be tested to Annex A, 
which provides testing methods and accuracy tolerances that differ from 
those contained in the sections that DOE proposed to incorporate by 
reference in the test procedure NOPR. As a result, DOE concludes that 
it is not appropriate to include liquid ring compressors in the scope 
of this test procedure final rule. However, DOE retains the authority 
to evaluate and propose appropriate test methods for liquid ring 
compressors in future rulemakings.
---------------------------------------------------------------------------

    \9\ In this final rule, DOE is incorporating by reference parts 
of ISO 1217:2009(E) as amended by Amendment 1:2016. Amendment 1:2016 
did not introduce any changes in regards to this particular topic.
---------------------------------------------------------------------------

3. Driver Style
a. Electric Motor- and Engine-Driven Compressors
    In the test procedure NOPR, DOE proposed to limit the scope of the 
compressors test procedure to only compressors driven by electric 
motors. In response, EEI expressed disappointment that the scope of the 
proposed energy conservation standard for compressors and, by 
extension, the test procedure was not fuel-neutral, noting that there 
are compressors driven by natural gas. (Docket No. EERE-2013-BT-STD-
0040, EEI, Public Meeting Transcript, No. 0044 at p. 5)
    In response to EEI's comment, DOE considered engine-driven 
compressors in the February 5, 2014 Framework document for compressors 
and discussed these extensively in the May 5, 2016 test procedure NOPR. 
79 FR 6839 and 81 FR 27220. Specifically, in the test procedure NOPR, 
DOE concluded that the inclusion of engine-driven compressors was not 
appropriate for various reasons, including their differing utility as 
compared to electric compressors, their existing coverage under the 
U.S. Environmental Protection Agency's Tier 4 emissions regulations, 
and the limited test data available under Annex D of ISO 1217:2009(E) 
to verify suitability as a DOE test procedure. For these reasons, DOE 
noted that engine-driven compressors would more appropriately be 
considered as part of a future rulemaking. 81 FR 27220, 27229 (May 5, 
2016). DOE continues to conclude that engine-driven compressors are 
unique equipment with different performance, applications, and test 
requirements from air compressors driven by electric motors. However, 
as noted in the test procedure NOPR, DOE currently lacks the 
performance data and product information to develop and validate such 
procedures. Therefore, DOE continues to conclude engine-driven 
compressors would be more appropriately addressed as part of a separate 
rulemaking specifically considering such equipment. As such, DOE is 
limiting the scope of this compressors test procedure final rule to 
only compressors driven by electric motors.
b. Electric Motor Varieties
    In the test procedure NOPR, DOE proposed limiting the scope of the 
compressors test procedures to only compressors driven by brushless 
electric motors, as defined in section III.A.5. Further, DOE discussed 
the differences between brushed and brushless motors and noted that 
brushed motors are uncommon in compressors with significant operating 
hours due to higher maintenance requirements, lower efficiency, 
acoustic noise, and electrical arcing. However, DOE noted that 
compressors with brushed motors could be considered in the future as 
part of a separate rulemaking. 81 FR 27220, 27229 (May 5, 2016).
    In response to DOE's test procedure NOPR, NEEA stated that 
manufacturers may avoid regulation by changing the motor technology. 
(NEEA, Public Meeting Transcript, No. 0016 at p. 56) In response, DOE 
reiterates that brushed motors are uncommon in compressors with 
significant potential energy savings (i.e., high operating hours) due 
to higher maintenance costs, short operating lives, significant 
acoustic noise, and electrical arcing. For these reasons, DOE concludes 
that brushed motors are not a viable substitution risk for compressors 
within the scope of the compressor test procedures.
    In a joint comment, ASAP and NEEA recommended that DOE expand the 
scope of the test procedures so that it includes all kinds of electric 
motors, rather than exclusively covering brushless motors. ASAP and 
NEEA reasoned that the test procedures should be broad so that they 
could be applicable to possible future energy conservation standards 
and could be used to collect a wide range of compressor performance 
data. (ASAP and NEEA, No. 0015 at p. 1)
    In response, DOE acknowledges the potential benefits of 
standardized test procedures and reporting requirements in making 
available consistent performance information for utility programs and 
consumers. However, with these potential benefits come potential 
burdens. If DOE were to include this equipment in the scope of the test 
procedures and require reporting of performance data, the burden would 
be significant, as most brushed motor compressors are not currently 
tested for efficiency. Consequently, manufacturers of this equipment, 
many of which are small, would face significant third-party testing 
costs or test lab development costs. Alternatively, DOE could adopt 
optional testing and certification requirements for brushed motor 
compressors. However, doing so may not have the desired effect of 
making more certified performance data available, as this equipment is 
not currently tested and energy performance is not currently 
represented. Therefore, based on this discussion, at this time, the 
burden associated with establishing testing requirements for brushed 
motor compressors outweigh the associated benefits.
4. Compressor Capacity
    In the test procedure NOPR, DOE proposed to limit the scope of the 
test procedures to compressors that met the following capacity 
criteria:
     Compressor motor nominal horsepower of 1-500 hp.
     full-load operating pressure 31-225 psig.
    81 FR 27220, 27230 (May 5, 2016).
    In the test procedure NOPR, DOE did not propose scope restrictions 
based on the actual volume flow rate (expressed in cfm).
    As noted in the test procedure NOPR, the intent of the compressor 
capacity criteria used to establish the scope of the test procedures 
was to encompass the majority of the rotary and reciprocating 
compressor market

[[Page 1061]]

intended for use in non-specialty applications. 81 FR 27220, 27224-
27230 (May 5, 2016). However, in the test procedure NOPR, DOE noted 
that most equipment operating at an output pressure of greater than 215 
psig is highly engineered equipment, primarily used in specialty 
applications. DOE also recognized that there are relatively few 
compressed air applications in the 31 to 79 psig range. 81 FR 27220, 
27230 (May 5, 2016).
a. Compressor Motor Nominal Horsepower Limitations
    In response to the proposed compressor motor nominal horsepower 
scope of 1-500 hp, CAGI recommended limiting the scope of the test 
procedures to compressors with compressor nominal motor horsepower of 
10-200 hp. CAGI suggested that the inclusion of larger compressors 
(i.e., greater than 200 hp) would be burdensome and cause problems with 
certification and enforcement as they are infrequently built and often 
customized. Further, CAGI noted that while the test procedures are 
technically appropriate for 1-500 hp compressors, the data upon which 
the energy conservation standard regression curves were developed is 
not readily available for smaller and larger compressors. (CAGI, No. 
0010, p. 6) Kaeser Compressors, Ingersoll Rand, Sullair, and Sullivan-
Palatek supported CAGI's scope suggestion, while Scales Industrial 
Technologies suggested a horsepower scope of 15-200 or 250 hp. 
(Ingersoll Rand, No. 0011 at p. 1; Sullair, No. 0006 at pp. 1-8; 
Sullivan-Palatek, No. 0007 at pp. 1, 3; Scales Industrial Technologies, 
No. 0013 at pp. 3, 7; Kaeser Compressors, Public Meeting Transcript, 
No. 0016 at p. 46; Sullair, Public Meeting Transcript, No. 0016 at pp. 
40-41, 47; Sullivan-Palatek, Public Meeting Transcript, No. 0016 at p. 
56; Ingersoll Rand, Public Meeting Transcript, No. 0016 at p. 53)
    Compressed Air Systems commented that there are few 1-hp rotary 
compressors manufactured and suggested that the test procedures burden 
would outweigh the energy savings potential. (Compressed Air Systems, 
No. 0008 at p. 1) Sullair agrees that the test procedure for low 
horsepower compressors would be burdensome, but commented that the 
volume of compressors manufactured in the low horsepower range are 
high. (Sullair, No. 0006 at pp. 5-6) P. R. China also commented that 
the DOE did not provide adequate justification to include low 
horsepower compressors in the scope of the test procedure. (P. R. 
China, No. 0019 at p. 3) P. R. China further stated that, in accordance 
with Article 2.5 of the TBT Agreement, they are entitled to an 
explanation for the justification for a technical regulation that may 
impact the trade opportunities of those in the agreement. (P. R. China, 
No. 0019 at p. 3) DOE interprets P. R. China's comments as challenging 
the rationale of including small capacity compressors with small 
nominal horsepower motors in the scope of the test procedure NOPR.
    Sullair suggested that the testing burden associated with including 
rotary compressors less than 10 hp and greater than 200 hp in scope 
would create an unfair competitive advantage for non-regulated 
competing equipment; specifically, reciprocating or scroll compressors 
on the low end and centrifugal compressors on the high end. Sullair 
indicated that such burden may completely eliminate the larger rotary 
screw compressors from the market and significantly hurt the sales of 
the smaller ones. (Sullair, No. 0006 at pp. 2-3, 5-6) Kaeser 
Compressors indicated similar concerns of product substitution, citing 
350 hp, rather than 200 hp. (Kaeser Compressors, Public Meeting 
Transcript, No. 0016 at p. 51) Beyond the financial burden, CAGI and 
Sullair commented about the difficulty of testing large compressors 
over 200 horsepower. Specifically, Sullair stated that the test 
equipment and environmental chamber required for compressors above 200 
horsepower are unreasonably costly. (Sullair, No. 0006 at p. 4; CAGI, 
Public Meeting Transcript, No. 0016 at p. 50)
    Kaeser Compressors further stated that compressor customization, 
such as customer-driven motor substitutions or modifications due to 
unique environments, are more common on units above 300 hp. (Kaeser 
Compressors, Public Meeting Transcript, No. 0016 at p. 46) CAGI, 
Sullair, and Sullivan-Palatek made similar comments, noting that large 
horsepower compressors are more frequently customized. Sullair and 
Sullivan-Palatek defined large horsepower compressors as compressors 
with greater than 200 horsepower. (CAGI, No. 0010 at p. 6; Sullair, No. 
0006 at p. 4; Sullair, No. 0006 at pp. 7-8; Sullivan-Palatek, No. 0007 
at p. 3)
    Additionally, CAGI cited that its current Performance Verification 
Program covers compressors with motor power of 5-200 hp. CAGI clarified 
that manufacturers may publicly rate equipment beyond 200 hp with the 
CAGI performance data sheet; however, this equipment is not subject to 
the CAGI Performance Verification Program. (CAGI, Public Meeting 
Transcript, No. 0016 at pp. 50, 54-55) Conversely, Atlas Copco and the 
CA IOUs recommended that DOE expand the scope of the test procedures to 
equipment with compressor motor horsepower greater than 500 hp, with 
Atlas Copco citing harmonization with the draft EU standard for 
compressors and noting that the ISO 1217:2009(E) standard is applicable 
to compressors above 500 horsepower. (Atlas Copco, No. 0009 at p. 11; 
CA IOUs, No. 0012 at p. 4)
    In response to the 2012 NOPD, EEI argued that large electric motors 
(i.e., of greater than 500 horsepower), relative to other sizes, 
carried the greatest per-unit energy consumption and tended to be 
operated at high duty cycles. EEI noted that this tendency to operate 
at high duty cycles may simplify development of a test procedure and 
that, on the account of both test procedure simplicity and large unit 
energy consumption, DOE should prioritize large compressors and common 
gases. (Docket No. EERE-2012-BT-DET-0033, EEI, No. 0009, at p. 8)
    In summary, one group of commenters (CAGI, Compressed Air Systems, 
Kaeser Compressors, Ingersoll Rand, P. R. China, Scales Industrial 
Technologies, Sullair, and Sullivan-Palatek) favors a significant 
reduction in compressor motor nominal horsepower scope (to 
approximately 10-200 hp, depending on commenter). This group suggests 
that significant test burden would be incurred if the smaller and 
larger horsepower range were to be kept in scope, and this burden could 
lead to competitive advantage for unregulated compressors. This group 
also cites weakness in the data used to evaluate less than 10 hp 
compressors in the energy conservation standards NOPR as a reason to 
limit the lower horsepower range. Another group (Atlas Copco, CA IOUs, 
and EEI) favors expansion of scope to all equipment for which the test 
method is technically applicable. EEI, while not outright calling to 
exclude lower horsepower ratings, implies that DOE's first attention 
should go to larger compressors.
    In general, DOE agrees with the concerns that the representations, 
sampling, and enforcement provisions proposed in the test procedure 
NOPR may cause significant burden for compressors greater than 200 hp, 
as many of the larger horsepower models are custom or infrequently 
built and typically not available for testing. Additionally, DOE agrees 
with Kaeser Compressors and Sullair that DOE's proposed inclusion of 
small (less than 10 hp) and larger (greater than 200 hp) rotary 
compressors, could create a competitive disadvantage for

[[Page 1062]]

manufacturers of these compressors, as centrifugal, reciprocating, and 
scroll compressors of the same horsepower do not have the same testing 
and representations requirements. Furthermore, DOE concludes that this 
competitive advantage may incentivize end users to switch from a 
regulated (rotary) to an unregulated (centrifugal and reciprocating) 
compressor, thus creating an unfair and undue burden on certain 
manufacturers.
    In response to Atlas Copco and the CA IOUs suggestions to expand 
scope, DOE acknowledges the potential benefits of standardized test 
procedures and reporting requirements in making available consistent 
performance information for utility programs and consumers. However, 
DOE also recognizes that with these potential benefits come potential 
burdens. Based on the comments received and the discussion in this 
section, DOE concludes that the burden of testing requirements on 
compressors certain smaller and larger compressors outweigh the 
benefits. DOE acknowledges that multiple recommendations for horsepower 
limitations were put forward. Of the commenters supporting a reduction 
in horsepower cost, the overwhelming majority recommended the 10-200 hp 
range. For these reasons, DOE is limiting the scope of the test 
procedures to only compressors with 10-200 compressor nominal motor 
horsepower. DOE notes that this limitation on compressor nominal motor 
horsepower is coupled with a limit of compressor full-load actual 
volume flow rate, as discussed in section III.B.4.b.
b. Full-Load Actual Volume Flow Rate Limitations
    CAGI and Sullair commented that the absence of a maximum airflow 
limit may encourage manufacturers of compressors to equip units with 
higher horsepower motors than the unit requires to avoid regulatory 
coverage. CAGI and Sullair then suggested that DOE adopt a hybrid scope 
limitation. Specifically, CAGI proposed a horsepower range of 10-200 hp 
or an actual volume flow rate range of 35-1,250 cfm. Sullair proposed a 
horsepower range of 10-200 hp or, an actual volume flow rate of 30-
1,250 cfm (whichever is less). (Docket No. EERE-2013-BT-STD-0040, CAGI, 
No. 0052 at p. 9; Sullair, No. 0006 at pp. 2, 4-5; Docket No. EERE-
2013-BT-STD-0040, Sullair, No. 0056 at pp. 9-10; Docket No. EERE-2013-
BT-STD-0040, Sullair, No. 0056 at p. 11; Docket No. EERE-2013-BT-STD-
0040, Sullair, No. 0056 at pp. 11-12; Docket No. EERE-2013-BT-STD-0040, 
Sullair, No. 0056 at p. 13) CAGI's position is supported by Ingersoll 
Rand, Kaeser Compressors, Sullair, and Sullivan-Palatek. (Docket No. 
EERE-2013-BT-STD-0040, Ingersoll Rand, No. 0055 at p. 1; Docket No. 
EERE-2013-BT-STD-0040, Kaeser Compressors, No. 0053 at p. 1; Docket No. 
EERE-2013-BT-STD-0040, Sullair, No. 0056 at p. 1; Docket No. EERE-2013-
BT-STD-0040, Sullivan-Palatek, No. 0051 at p. 1)
    DOE agrees with CAGI and Sullair that, by not limiting flow rate, 
manufacturers could conceivably circumvent the intent of compressor 
regulations by using a motor of horsepower slightly greater than 200 
hp. For example, two similar compressors, one with a 200 hp motor and 
one with a 225 hp motor, would supply nearly identical flow rates and 
pressure (i.e., utility) to the end user, however the compressor 
equipped with the 225 hp motor would not be subject to the test 
procedure, as proposed in the NOPR. In DOE's view, any alteration in 
flow rate directly impacts consumer utility. Additionally, a flow 
limitation is consistent with the EU Lot 31 draft standard, which 
proposes to regulate compressors with airflow of between 5 and 1,280 
liters per second (l/s) (approximately 10.6-2,712 cfm).
    A review of all available CAGI performance data sheets indicates 
that the flow rate ranges recommended by CAGI and Sullair are 
reasonable. The full-load actual volume flow rate range of 35-1,250 cfm 
is slightly broader than the compressor motor nominal horsepower range 
of 10-200 hp; i.e., the flow range encompasses slightly more compressor 
models. This aligns with the intent of the recommendations put forth by 
CAGI and Sullair. Specifically, the full-load actual volume flow rate 
range of 35-1,250 cfm incorporates 9.2 percent more fixed-speed 
compressors and 2.9 percent more variable-speed compressors as subject 
to the test procedure than would otherwise be included with the 
compressor motor nominal horsepower range of 10-200 hp alone. For the 
reasons outlined in this section, in this final rule, DOE adopts a 
coupled airflow and horsepower limit, as recommended by Sullair and 
CAGI. DOE notes that the recommendations from Sullair and CAGI are not 
completely aligned, with Sullair recommending a lower limit of 30 cfm 
and CAGI recommending a lower limit of 35 cfm. Given general support by 
Ingersoll Rand, Kaeser Compressors, Sullair, and Sullivan-Palatek for 
CAGI's recommendations, DOE is adopting the lower limit of 35 cfm. 
Specifically, the test procedure applies to compressors with either a 
nominal horsepower of 10-200 horsepower or a full-load actual volume 
flow rate between 35-1,250 cubic feet per minute.
c. Full-Load Operating Pressure Limitations
    In response to the operating pressure range proposed in the test 
procedure NOPR, CAGI suggested reducing the range to compressors with a 
full-load operating pressure of 75-200 psig, noting that outside this 
range, the package isentropic efficiency of a compressor is no longer 
independent of pressure. (CAGI, No. 0010 at p. 6) Ingersoll Rand, 
Sullair, and Sullivan-Palatek supported CAGI's position. (Ingersoll 
Rand, No. 0011 at p. 1; Sullair, No. 0006 at p. 1; Sullivan-Palatek, 
No. 0007 at p. 1; Sullivan-Palatek, No. 0007 at p. 3; Sullivan-Palatek, 
Public Meeting Transcript, No. 0016 at p. 40) CAGI further stated that 
their recommended pressure range of 75-200 psig covers the primary 
market for rotary compressors, which the DOE defines as 80-139 psig 
according to the NOPR. (CAGI, Public Meeting Transcript, No. 0016 at p. 
40) Jenny Products also recommended a range of 75-200 psig and stated 
that nearly all of the compressors sold in commerce would be covered 
under this range. (Jenny Products, No. 0020 at p. 3)
    Atlas Copco asserted that it is incorrect for DOE to state that 
isentropic efficiency is independent of pressure. Instead, Atlas Copco 
commented that the correct statement is that isentropic efficiency is 
less dependent on pressure than specific energy is dependent on 
pressure. To support this assertion, Atlas Copco provided a chart of 
pressure versus isentropic efficiency, for what DOE infers to be a 
single compressor. Atlas Copco further stated that the chart shows the 
relative independence of isentropic efficiency with respect to outlet 
pressure between 80-170 psig (7-15 bar),\10\ which was the motivation 
for the air compressor industry to use isentropic efficiency in Lot 31. 
(Atlas Copco, No. 0009 at pp. 16-17) DOE notes that Atlas Copco's unit 
conversions are incorrect; 80 to 170 psig does not convert to 7 to 15 
bar (g), rather this range converts to 5.5 to 11.7 bar (g) (or 6.5 to 
12.7 bar absolute), which is inconsistent with the scope proposed in 
the EU Lot 31 draft standard.\11\ In the EU draft standard, the

[[Page 1063]]

European Commission proposed to establish a scope of 7 to 14 bar (g), 
which converts to 101.5 to 203.1 psig.
---------------------------------------------------------------------------

    \10\ The commenter did not specify whether it meant absolute or 
gauge pressure. DOE's response in the following sentence addresses 
both possibilities.
    \11\ Available at: https://www.regulations.gov/contentStreamer?documentId=EERE-2013-BT-STD-0040-0031&disposition=attachment&contentType=pdf.
---------------------------------------------------------------------------

    In response, DOE acknowledges the commenters concerns that package 
isentropic efficiency may not be pressure independent at the lower and 
upper regions of the 31 to 225 psig full-load operating pressure scope, 
as DOE had originally assumed in the test procedure and energy 
conservation standards NOPR. As discussed previously, CAGI, Ingersoll 
Rand, Sullivan-Palatek, and Sullair suggested 75 to 200 psig as the 
range over which package isentropic efficiency can be considered 
relatively independent of pressure. Alternatively, Atlas Copco 
suggested that 80 to 170 psig (7 to 15 bar) [sic] as the range over 
which the dependence of isentropic efficiency on outlet pressure is 
limited. However, as discussed previously, Atlas Copco's unit 
conversions were inaccurate and their suggested range does not align 
with the scope proposed in the EU Lot 31 draft standard. Based these 
ambiguities, DOE cannot directly consider Atlas Copco's recommendation 
when considering the range for which package isentropic efficiency can 
be considered independent of full-load operating pressure. As such, DOE 
defers to the recommendation of CAGI, Ingersoll Rand, Sullivan-Palatek, 
and Sullair, and concludes that package isentropic efficiency can be 
considered independent of full-load operating pressure at full-load 
operating pressures between 75 and 200 psig. DOE notes that the EU 
draft standard proposed to establish a scope of 101.5 to 203.1 
psig,\12\ and concluded that isentropic efficiency is independent of 
pressure within this range of full-load operating pressure. Part of 
DOE's rationale for selecting package isentropic efficiency as a test 
metric for compressors, as explained in the test procedure NOPR, was 
that package isentropic efficiency was believed to be pressure 
independent--meaning that attainable package isentropic efficiency 
varies as function of flow, but not pressure. 81 FR 27220, 27232 (May 
5, 2016) and 81 FR 31680, 31705 (May 19, 2016). DOE values dependence 
on one parameter (flow) rather than two (flow and pressure), as it 
reduces the complexity (and ultimately the burden) of the related 
energy conservation standards and analyses. DOE's intent in the test 
procedure NOPR was to limit the scope to those compressors for which 
package isentropic efficiency and pressure are independent. However, 
given the new information (i.e., pressure dependence at certain full-
load operating pressures), DOE acknowledges that package isentropic 
efficiency may not be the most appropriate metric to describe the 
energy performance of such equipment, and further investigation is 
necessary. Therefore, in this final rule, DOE is limiting the scope of 
the test procedures to compressors within a full-load operating 
pressure range of 75-200 psig. However, in the future DOE may further 
investigate package isentropic efficiency and other metrics to 
determine if they are appropriate for compressors outside this range. 
Further discussion related to DOE's selection of package isentropic 
efficiency as a metric can be found in section III.C.1.
---------------------------------------------------------------------------

    \12\ For copies of the EU Lot 31 draft regulation: 
www.regulations.gov/contentStreamer?documentId=EERE-2013-BT-STD-0040-0031&disposition=attachment&contentType=pdf.
---------------------------------------------------------------------------

    DOE notes that Scales Industrial Technologies commented that the 
scope should be limited to a narrower range of 80-125 psig, commenting 
that a narrower range may provide more meaningful results and have less 
effect on isentropic efficiency. (Scales Industrial Technologies, No. 
0013, p. 4) While Scales Industrial Technologies may be correct that a 
narrower range would have less effect on isentropic efficiency, DOE 
concludes, based on the input of CAGI, Ingersoll Rand, Sullivan-
Palatek, Sullair, and Atlas Copco, as well as the precedent established 
by the draft EU Lot 31 regulation, that isentropic efficiency can be 
considered comparable and meaningful beyond the 80 to 125 psig range.
5. Lubricant Presence
    As discussed in section III.A.9, in this final rule DOE adopts the 
definition proposed in the energy conservation standards NOPR for 
lubricated compressor as one that introduces an auxiliary substance 
into the compression chamber during compression. In this final rule, 
DOE also defines lubricant-free compressor and auxiliary substance. In 
the test procedure NOPR, DOE did not propose limiting scope based on 
lubrication; as such, the proposed scope implicitly included both 
lubricated and lubricant-free compressors. 81 FR 27220 (May 5, 2016).
    In response to DOE's proposal, Atlas Copco, CAGI, and Kaeser 
Compressors noted that other technology options that are outside the 
scope of the test procedure, such as turbo compressors, centrifugal 
compressors, and other styles of dynamic compressors, will present 
themselves as viable alternatives to lubricant-free compressors and are 
risks for unregulated product substitution. (EERE-2013-BT-STD-0040, 
Atlas Copco, Public Meeting Transcript, No. 0044 at p. 58) Furthermore, 
Kaeser Compressors noted that the draft EU standard for compressors 
excluded lubricant-free compressors due to the risk of product 
substitution and lack of available data. CAGI and Kaeser recommended 
that DOE exclude lubricant-free compressors so that the DOE can 
harmonize with the draft EU compressor standard's approach for 
lubricant-free compressors. (EERE-2013-BT-STD-0040, CAGI, No. 0052 at 
p. 12; EERE-2013-BT-STD-0040, Kaeser Compressors, No. 0053 at p. 1)
    DOE agrees with comments made by Atlas Copco, CAGI, and Kaeser that 
there is a risk of product substitution to unregulated technologies, 
which do not have the burden of representing efficiency in accordance 
to the proposed test procedure. DOE acknowledges that, in effect, the 
inclusion of lubricant-free rotary compressors gives unregulated 
technologies a competitive advantage in the marketplace in that they 
are free to represent efficiency in a less burdensome fashion. DOE also 
acknowledges an argument made by CAGI, which point out that the 
shipments volume of lubricant-free rotary compressors and dynamic 
compressors are approximately equal, yet DOE excluded centrifugal 
compressors from the scope of the test procedure on the basis of low 
shipment volume. (EERE-2013-BT-STD-0040, CAGI, No. 0052 at p. 12) 81 FR 
27220, 27228 (May 5, 2016).
    DOE also received many comments related to the appropriateness and 
applicability of the variable-speed compressors test method and metric 
(part-load package isentropic efficiency) to lubricant-free 
compressors. In general, commenters expressed concern that many 
lubricant-free compressors are unable to operate at the 40 percent flow 
load point, and as such, suggested that the test procedure, as proposed 
in the test procedure NOPR is not appropriate or applicable to 
lubricant-free compressors. A full discussion of these comments and 
their relationship to scope is found in section III.C.1, which 
discusses, in the depth, the metric and load points proposed in the 
test procedure NOPR. As a result of the discussions provided in section 
III.C.1, DOE is limiting the scope of the test procedure final rule to 
lubricated compressors only.
6. Specialty-Purpose Compressors
    In the test procedure NOPR, DOE made no specific scope exclusion 
for

[[Page 1064]]

what the compressor industry refers to as ``customized'' or 
``specialty-purpose'' compressors. In response, DOE received many 
comments recommending that it expressly exclude specialty-purpose 
compressors from the scope of the test procedure. Additionally, many 
commenters suggested that DOE establish criteria to exclude customized 
compressors that are created by modifying a standard compressor.
    Sullivan-Palatek commented that compressor products usually start 
with the basic package, but often substitute non-standard electric 
motors, controls or coolers and add numerous other options and features 
specified by the customer or required by the location in which the 
compressor is installed. (Sullivan-Palatek, No. 0007 at p. 22)
    Sullair provided examples of custom requirements, such as sump 
heating, extra fans, and special marine applications for which motors 
have to be built (American Bureau of Shipping), and noted that these 
frequently increase package energy consumption. (Sullair, Public 
Meeting Transcript, No. 0016 at p. 113)
    Atlas Copco commented that the test procedures proposed in the NOPR 
applied to both standard compressor packages and custom compressor 
packages, and the latter often have unusual combinations of ancillary 
equipment. Atlas Copco provided examples of custom equipment, including 
customized liquid cooling systems, drive systems, safety systems, 
filtration systems, dryers, heaters, and air receiver/surge tanks. 
Atlas Copco also noted that each type of customization can have a 
significant impact on the energy efficiency of the total compressor 
system. Ultimately, Atlas Copco suggested that applying the proposed 
test procedure to custom orders for compressor packages was unduly 
burdensome to conduct and inappropriate under section 343(a)(2) of 
EPCA. (Atlas Copco, No. 0009 at pp. 4-7)
    To address the industry concerns over the testing of customized and 
specialty-purpose compressors, CAGI recommended that the list of 
ancillary equipment they provided (see section III.A.3.b and Table 
III.1) should exclude all options or modifications required to meet 
specific customer requirements or other codified standards where these 
options or modifications are made to an existing tested model and do 
not create in and of themselves a new model. Examples may include 
options or modifications required to meet hazardous locations, 
breathing air, marine environments, ambient conditions above 45 [deg]C 
or below 0 [deg]C, weather protection, etc. (CAGI, No. 0010, p. 4)
    Sullair agreed with CAGI's recommendation and provided additional 
examples of custom requirements, including hazardous locations or 
corrosive environments (as specified by the standard known as 
Atmosph[egrave]res Explosibles, or ``ATEX'') \13\ or issued by the 
American Petroleum Institute (``API''), the Mine Safety and Health 
Administration (``MSHA''), etc.), marine environments, alternate 
cooling methods (remote coolers, water cooled, closed loop cooling, 
etc.), ambient conditions exceeding 45 [deg]C, ambient conditions below 
5 [deg]C, energy or heat recovery options, environmental protections 
(NEMA 4, IEC 65, etc.), and dimensional changes or enclosure 
modifications. (Sullair, No. 0006 at p. 8)
---------------------------------------------------------------------------

    \13\ ATEX is the common industry phrasing for European 
Parliament and Council Directive 2014/34/EU of 26 February 2014, 
which governs equipment and protective systems intended for use in 
potentially explosive atmospheres. The term ``ATEX'' is a 
portmanteau of ``atmosph[egrave]res explosibles'', French for 
``explosive atmospheres.''
---------------------------------------------------------------------------

    In its comments, Sullivan-Palatek strongly urged the DOE to limit 
testing and sampling to the basic package as defined by CAGI. It also 
recommended that DOE permit add-ons and alterations to basic packages 
so that specialty products offered to the end-user customer base in the 
past can continue in the future. (Sullivan-Palatek, No. 0007 at p. 4)
    As discussed in sections III.A.3.b and III.E.3, DOE is 
incorporating CAGI's recommended list of equipment (with certain 
modifications) to define the minimum testing configuration for a 
compressor basic model. DOE believes that the incorporation of this 
recommendation effectively excludes, from the scope of the test 
procedure, customized or specialty-purpose equipment that is created by 
adding additional equipment to what the industry refers to as a 
standard or basic package compressor.
    Based on DOE's interpretation of the comments described above, two 
additional concerns remain: (1) Specialty-purpose equipment that is 
created by modifying or replacing equipment on a standard package 
compressor, and (2) specialty-purpose equipment that is not a 
derivative of other standard equipment. However, DOE notes that the 
commenters provided no specific examples of specialty-purpose 
compressors that have been distributed in commerce, nor did they 
provide any direct or quantitative evidence that such compressors 
consume more energy and are more burdensome to test than their 
``general-purpose'' counterparts (beyond noting that more models may 
need to be certified). Regardless, given the commenters' concerns, DOE 
performed research (using interested party comments as a starting 
point) to determine if any additional scope exclusions are warranted. 
Specifically, DOE was able to identify 10 applications and feature 
categories that could possibly be used to characterize specialty-
purpose compressors in the compressor industry:

(1) Corrosive Environments
(2) Hazardous Environments (combustion and/or explosion risk)
(3) Extreme Temperatures
(4) Marine Environments
(5) Weather-protected
(6) Mining Environments
(7) Military Applications
(8) Food Service Applications
(9) Medical Air Applications
(10) Petroleum, Gas, and Chemical Applications

    Given the concerns raised by commenters, DOE established three 
specific criteria to help determine if test procedure exclusions are 
warranted for each of the aforementioned applications and feature 
categories. A compressor category must meet all criteria to be 
considered for exclusion.
    The first criterion, distinguishability, is that compressors under 
consideration must be able to be distinguished from general-purpose 
compressors. In this case, to be distinguishable extends beyond being 
able to identify any difference whatsoever. Specifically, 
distinguishability is determined in the context of the test procedure. 
DOE's test procedure final rule contains instructions regarding 
compressor configuration during testing. During a test, only specific 
components are required to be connected; manufacturers may remove non-
required components at their option. If the specialized nature of a 
compressor arises from a non-required component, manufacturers have the 
option to remove its influence on compressor performance. In that 
scenario, the specialty compressor, from the perspective of the test 
procedure, has collapsed to a general-purpose unit with no remaining 
distinction. In considering whether a compressor meets the 
distinguishability criterion, DOE will assess whether the specialized 
nature of the compressor arises from components or configurations that 
are removable or reconfigurable under the specific provisions of DOE's 
test.
    As stated previously, DOE is incorporating CAGI's recommended list 
of equipment (with certain modifications), so the only specialty-

[[Page 1065]]

purpose compressors that could warrant exclusion are those that are 
created by modifying or replacing equipment on a standard package 
compressor, and specialty-purpose equipment that is not derivative of 
other standard equipment.
    Under the second criterion, manufacturers must currently make 
public representations for the specific category of compressors using 
test procedure metrics. This criterion establishes the need to use the 
test procedure for the specific category. Absent an energy conservation 
standard, the test procedure is needed only to measure metrics used in 
representations of compressor performance. If manufacturers make no 
representations for a specific category of compressors, the existence 
of a test procedure has no impact on them. Sullivan-Palatek commented 
that manufacturers typically do not publish CAGI datasheets for models 
that are variations of a basic package. (Sullivan-Palatek, No. 0007 at 
p.4) This suggests that it is rare for manufacturers to make public 
representations of the performance for specialty-purpose compressors.
    The third criterion is that it must be impractical to apply the 
test procedure to compressors in the specific category, because an 
attribute of the compressor renders testing technically impossible or 
possible only with major modification, or because the test procedure 
produces non-representative results for the specific category of 
compressor. This criterion establishes that there is a technical 
impediment to using the test procedure with the specific category of 
compressors.
    DOE performed research, using publicly available data, on each of 
the categories to determine if exclusions are warranted. In the 
following paragraphs, DOE discusses findings for each of the 
aforementioned ten specialty applications.
Corrosive Environments
    Corrosive environments can be damaging to both the external 
components of a compressor and the internal components, if corrosive 
agents are ingested with the air. DOE's research indicated that 
corrosive agents are found in a wide range of varieties and severities. 
Certain corrosive agents may harm some materials but not others.
    Compressors may be adapted to corrosive environments by using 
special materials, having special coatings, using additional intake air 
filtration, or using special or remote enclosures to isolate the 
compressor from the corrosive environment. However, most requirements 
for corrosive environments are customer-specific, making it difficult 
to create a generalized scope exclusion. Some end users also use 
general-purpose compressors in a corrosive environment, opting to 
replace the compressor at an earlier interval instead of purchasing a 
more expensive compressor that can last longer in the corrosive 
environment.
    Based on this information, DOE does not believe that all corrosive 
environment compressors meet the first criterion of distinguishability; 
however certain corrosive environment compressors utilizing special 
materials and/or coatings may be distinguishable.
    DOE did not find any public representations of the performance for 
compressors designed for corrosive environments, suggesting that 
representations are not commonly posted.
    Finally, DOE found no evidence that testing with the test procedure 
is impractical for compressors designed for corrosive environments, 
because these compressors operate in the same manner as general-purpose 
compressors.
    Therefore, because manufacturers do not appear to make 
representations of performance for these compressors and there is no 
technical impediment to testing these compressors with the test 
procedure, DOE finds no cause to exclude compressors adapted to 
corrosive environments from the scope of this final rule.
Hazardous Environments
    Hazardous environments include those in which there is the 
possibility of combustion or explosion. Compressors may be adapted to 
hazardous environments through modified electrical components and 
enclosures that protect against sparks and high temperatures. At least 
some of these components need to be included as part of the basic 
package during testing. Several standards specify the type and level of 
precautions required for these environments, so certification with one 
or more of these could be a method for defining the scope of exclusion.
    For these reasons, DOE finds that hazardous environment compressors 
meet the first criterion of distinguishability. Hazardous environment 
compressors are designated as such by independent agencies such as UL, 
and given a rating that corresponds to the specific attributes of the 
hazardous environment for which the unit is being certified.
    DOE did not find any public representations of the performance for 
compressors designed for hazardous environments, suggesting that 
representations are not commonly posted.
    Finally, DOE found no evidence that testing with the test procedure 
is impractical for compressors designed for hazardous environments, 
because these compressors operate in the same manner as general-purpose 
compressors.
    Therefore, because manufacturers do not appear to make 
representations of performance for these compressors and there is no 
technical impediment to testing these compressors with the test 
procedure, DOE finds no cause to exclude compressors adapted to operate 
in hazardous environments from the scope of this final rule.
Extreme Temperatures
    CAGI and Sullair identified the need to exclude compressors used in 
extreme temperatures. (CAGI, No. 0010, p. 4; Sullair, No. 0006 at p. 8) 
For high-temperature extremes, both commenters identified temperatures 
above 45 [deg]C. For low-temperature extremes, Sullair indicated 
temperatures below 5 [deg]C, while CAGI indicated temperatures below 0 
[deg]C. DOE notes that CAGI and Sullair did not present any 
standardized tests or inspections that might be used to uniformly 
classify a non-extreme temperature range for compressors.
    In the absence of that information, DOE performed research and 
found neither industry-accepted, standardized test methods to determine 
allowable operating temperature, nor any industry-accepted 
certification programs to classify compressors for extreme 
temperatures. DOE also researched what types of modification and 
components might be employed to adapt compressors for extremely high- 
and low-temperature environments. For lower temperatures, a variety of 
heating devices may be used to heat the compressor package in various 
ways--such equipment is not required as a part of test procedure 
testing configuration and is, therefore, not a distinguishing feature.
    In hotter environments, compressors may employ larger output air 
heat exchangers and associated fans. Unlike package heating and 
cooling, heat exchangers and fans are part of the test configuration. 
However, manufacturers may employ larger heat exchangers and fans for a 
variety of reasons, e.g. recovering waste heat for use in space 
heating. Furthermore, heat exchanger and fan size (as compared to 
compressor capacity) is not a standardized feature across the 
compressor industry, with different manufacturers choosing different-
sized components to meet their specific design goals. Consequently, DOE 
is unable to establish a clear threshold to delineate larger heat 
exchangers and fans employed for high

[[Page 1066]]

temperature applications. Furthermore, doing so opens a significant 
circumvention risk, as manufacturers could purposely substitute larger 
heat exchangers and fans in order to exclude compressors from 
regulation. For these reasons, DOE concludes that compressors designed 
for extreme temperature operation are not clearly distinguishable from 
general-purpose compressors.
    DOE also did not find any public representations of the performance 
for compressors designed for extreme temperatures, suggesting that 
representations are not commonly posted.
    Finally, DOE found no evidence that testing with the test procedure 
is impractical for compressors designed for extreme temperatures, 
because these compressors operate in the same manner as general-purpose 
compressors.
    Therefore, because (a) it is difficult to clearly identify 
compressors for extreme temperatures; (b) manufacturers do not appear 
to make representations of performance for these compressors; and (c) 
there is no technical impediment to testing these compressors with the 
test procedure, DOE does not find cause to exclude compressors adapted 
to extreme temperatures from the scope of this final rule.
Marine Environments
    Marine air compressors are intended for use aboard ships, offshore 
platforms, and similar environments. In general, DOE found this to be a 
very broad category of compressors. There are a wide variety of 
standards for these applications, but many of the requirements are 
customer-specific, making it difficult to clearly identify the scope 
for exclusion. Marine compressors may be space constrained if installed 
on ships. However, this may not always be the case, and some marine 
environments may be able to utilize general-purpose compressors. 
Further, DOE found no way to clearly distinguish, from general-purpose 
compressors, those that are specifically developed for constrained 
spaces. DOE's research found that other items, such as saltwater 
coolers, may be employed on marine air compressors, however, this 
equipment does not need to be included for testing. For these reasons, 
DOE does not find marine environment compressors to meet the first 
criterion of distinguishability.
    DOE did not find any public representations of the performance for 
compressors designed for marine environments, suggesting that 
representations are not commonly made.
    Finally, DOE found no evidence that testing with the test procedure 
is impractical for compressors designed for marine environments, 
because these compressors operate in the same manner as general-purpose 
compressors.
    Therefore, because (a) it is difficult to clearly identify 
compressors for marine environments; (b) manufacturers do not appear to 
make representations of performance for these compressors; and (c) 
there is no technical impediment to testing these compressors with the 
test procedure, DOE does not find cause to exclude compressors adapted 
to marine environments from the scope of this final rule.
Weather-Protected
    Weather-protected compressors require features to prevent the 
ingress of water and debris, as well as accommodation for extreme 
temperatures in some cases. DOE found that third-party standards exist 
for ingress protection of the electrical components. However, DOE did 
not find an indication of a standard or certification for other aspects 
of weather protection, making it difficult to clearly identify a 
general scope for exclusion for all weather-protected equipment. 
However, DOE believes that certain weather-protected compressors (i.e., 
those with electrical components rated for ingress protection) meet the 
first criterion of distinguishability.
    DOE did not find any public representations of the performance for 
weather-protected compressors, suggesting that representations are not 
commonly posted.
    Finally, DOE found no evidence that testing with the test procedure 
is impractical for weather-protected compressors, because these 
compressors operate in the same manner as general-purpose compressors.
    Therefore, because manufacturers do not appear to make 
representations of performance for these compressors and there is no 
technical impediment to testing these compressors with the test 
procedure, DOE finds no cause to exclude compressors adapted to 
corrosive environments from the scope of this final rule.
Mining Environments
    Mining environments can include both surface and subsurface mine 
compressor applications. There are some standards for these 
applications, but many of the requirements are customer-specific, 
making it difficult to clearly identify the scope for exclusion. Some 
mining applications also use general-purpose compressors. For this 
reason, DOE does not find mining environment compressors to meet the 
first criterion of distinguishability.
    DOE did not find any public representations of the performance for 
compressors designed for mining environments, suggesting that 
representations are not commonly posted.
    Finally, DOE found no evidence that testing with the test procedure 
is impractical for compressors designed for mining environments, 
because these compressors operate in the same manner as general-purpose 
compressors.
    Therefore, because (a) it is difficult to clearly identify 
compressors designed for mining environments; (b) manufacturers do not 
appear to make representations of performance for these compressors; 
and (c) there is no technical impediment to testing these compressors 
with the test procedure, DOE does not find cause to exclude compressors 
designed for mining environments from the scope of this final rule.
Military Applications
    Compressors used in military applications have a wide range of 
applications. Many military applications use common commercial or 
industrial compressors. Other military applications, however, must meet 
extensive customer-specific requirements. These requirements can vary 
greatly with the customer, and there are no commonly used standards for 
compressors in military applications. This makes it difficult to 
clearly identify the scope for exclusion. For this reason, DOE does not 
find military compressors to meet the first criterion of 
distinguishability.
    DOE did not find any public representations of the performance for 
compressors designed for military applications, suggesting that 
representations are not commonly posted.
    Finally, DOE found no evidence that testing with the test procedure 
is impractical for compressors designed for military applications, 
because these compressors operate in the same manner as general-purpose 
compressors.
    Therefore, because (a) it is difficult to clearly identify 
compressors designed for military applications; (b) manufacturers do 
not appear to make representations of performance for these 
compressors; and (c) there is no technical impediment to testing these 
compressors with the test procedure, DOE does not find cause to exclude 
compressors designed for military applications from the scope of this 
final rule.

[[Page 1067]]

Food Service Applications
    Food service applications can have requirements for air purity and 
to use food-grade lubricants. Food grade lubricants need to be included 
for testing, so at least some compressors designed for food service 
applications meet the first criterion of distinguishability.
    DOE did not find any public representations of the performance for 
compressors designed for food service applications, suggesting that 
representations are not commonly posted.
    Finally, DOE found no evidence that testing with the test procedure 
is impractical for compressors designed for food service applications, 
because these compressors operate in the same manner as general-purpose 
compressors.
    Therefore, because manufacturers do not appear to make 
representations of performance for these compressors and there is no 
technical impediment to testing these compressors with the test 
procedure, DOE finds no cause to exclude compressors adapted to 
corrosive environments from the scope of this final rule.
Medical Air Applications
    Medical air applications can have requirements for air purity, 
which is both rated according to ISO 8573-1 and included in the 
National Fire Protection Association Standard for Health Care 
Facilities (NFPA 99). DOE notes that most medical air compressors are 
lubricant-free and, as such, are already excluded from this final rule. 
In lubricated compressors, high air purity is attained using a 
combination of filters and dryers added to the system downstream of the 
compressor discharge. These items are outside the basic compressor 
package, so a medical air compressor collapses to a standard basic 
package for testing. For this reason, DOE does not find medical air 
application compressors to meet the first criterion of 
distinguishability.
    DOE did not find any public representations of the performance for 
compressors designed for medical air applications, suggesting that 
representations are not commonly posted.
    Finally, DOE found no evidence that testing with the test procedure 
is impractical for compressors designed for medical air applications, 
because these compressors operate in the same manner as general-purpose 
compressors.
    Therefore, because (a) manufacturers do not appear to make 
representations of performance for compressors designed for medical air 
applications; (b) these compressors collapses to the basic package for 
testing; and (c) there is no technical impediment to testing these 
compressors with the test procedure, DOE does not find cause to exclude 
compressors designed for medical air applications from the scope of 
this final rule.
Petroleum, Gas, and Chemical Applications
    The American Petroleum Institute standard 619, ``Rotary-Type 
Positive-Displacement Compressors for Petroleum, Petrochemical, and 
Natural Gas Industries,'' (API 619), specifies certain minimum 
requirements for compressors used in the petroleum, gas, and chemical 
industry. While API 619 contains many specific design requirements, it 
also indicates that customers must specify many design requirements 
themselves. As a result, compressors designed to meet API 619 
requirements are not uniform; rather, they are, by definition, 
customized compressors. In addition to the design requirements, API 619 
imposes rigorous testing, data reporting, and data retention 
requirements on manufacturers. For example, manufacturers are required 
to perform specific hydrostatic and operational mechanical vibration 
testing on each individual unit distributed in commerce. Furthermore, 
manufacturers must retain certain data for at least 20 years, such as 
certification of materials, test data and results, records of all heat 
treatment, results of quality control tests and inspections, and 
details of all repairs. Based on these testing, data reporting, and 
data retention requirements, DOE concludes that compressors designed 
and tested to the requirements of API 619 meet the first criterion of 
distinguishability.
    Based on DOE's assessment of API 619, DOE believes that the minimum 
design and testing requirements specified in API 619 are created to 
achieve, among other goals, safety and reliability in the petroleum, 
gas, and chemical industry. These requirements ensure that the 
compressor can be operated and maintained safely, in the safety-
critical petroleum, gas, and chemical industry. Thus, there is not a 
current industry test procedure that would apply and it is unclear if 
the methodology being adopted in this final rule would be 
representative of their actual use. Thus, DOE is declining to adopt a 
test procedure for compressors designed for petroleum, chemical and gas 
applications.

C. Metrics

1. Package Isentropic Efficiency
    In the test procedure NOPR, DOE proposed ``package isentropic 
efficiency'' to be the energy metric for compressors, and defined 
package isentropic efficiency to mean the ratio of power required for 
an ideal isentropic compression process to the actual packaged 
compressor power input used at a given load point, as determined in 
accordance with the test procedures included in 10 CFR 431.344.\14\ 81 
FR 27220, 27232 (May 5, 2016). Because package isentropic efficiency is 
expressed relative to an ideal isentropic process between the same 
input and output pressures, it could therefore be used to compare units 
across a wide range of pressures. DOE presented this applicability 
across a wide range of pressures as an advantage of package isentropic 
efficiency over specific input power. Ibid.
---------------------------------------------------------------------------

    \14\ Test methods are discussed specifically in section III.E.
---------------------------------------------------------------------------

    Specifically, DOE proposed to establish two versions of package 
isentropic efficiency: Full-load package isentropic efficiency and 
part-load package isentropic efficiency. DOE proposed that full-load 
package isentropic efficiency would apply only to fixed-speed 
compressors, whereas part-load package isentropic efficiency would 
apply only to variable-speed compressors. Full-load package isentropic 
efficiency is evaluated at a single load point, while part-load package 
isentropic efficiency is a weighted composite of performance at 
multiple load points (or rating points). Equation 1 and Equation 2 
describe the full- and part-load package isentropic efficiency, as 
proposed in the test procedure NOPR.
[GRAPHIC] [TIFF OMITTED] TR04JA17.000


[[Page 1068]]


Where:

[eta]isen,FL = package isentropic efficiency at full-load 
operating pressure,

Pisen,100[ne] = isentropic power required for compression 
at full-load operating pressure, and

Preal,100[ne] = packaged compressor power input at full-
load operating pressure.
[GRAPHIC] [TIFF OMITTED] TR04JA17.001

Where:

[eta]isen,PL = part-load package isentropic efficiency,

[omega]i = weighting factor for rating point i,

Pisen,i = isentropic power required for compression at 
rating point i,

Preal,i = packaged compressor power input at rating point 
i, and

i = load points at 100, 70, and 40 percent of full-load actual 
volume flow rate.

    To clearly separate the two varieties of compressors, in the test 
procedure NOPR, DOE proposed the following definitions for fixed-speed 
and variable-speed compressors:
    Fixed-speed compressor means an air compressor that is not capable 
of adjusting the speed of the driver continuously over the driver 
operating speed range in response to incremental changes in the 
required compressor flow rate.
    Variable-speed compressor means an air compressor that is capable 
of adjusting the speed of the driver continuously over the driver 
operating speed range in response to incremental changes in the 
required compressor actual volume flow rate.
    DOE received a significant volume of comments regarding these 
metrics, associated load points and weights, and the applicability of 
each version of package isentropic efficiency. The following 
subsections discuss these issues and relevant comments in detail.
a. Use of Full-Load and Part-Load Package Isentropic Efficiency as 
Regulatory Metrics
    In response to DOE's proposal to use package isentropic efficiency 
as a metric, CASTAIR disagreed, stating that air compressors consume 
electricity (in kW, using electric motors that are already regulated) 
and produce flow (in cfm). CASTAIR further stated that power (in kW) 
and flow (in cfm) are very easy things to test and record, and 
suggested that DOE should then regulate, if it must, the efficiency 
between the two (i.e., kW and cfm) for air ends. (CASTAIR, No. 0018 at 
p. 1) Based on this comment, DOE interprets that CASTAIR is suggesting 
that the efficiency of the compressor should be a simple calculation 
based on the regulated representation of efficiency for the electric 
motor and the airflow produced by the air compressor. In response to 
this suggestion, DOE clarifies that the efficiency and energy 
consumption of an air compressor is not solely a function of the motor. 
As DOE discussed in the energy conservation standards NOPR, 
opportunities exist to select or design higher efficiency motors, 
drives (if applicable), bare compressors (including multi-staging), 
mechanical equipment, and ancillary equipment. 81 FR 31680, 31701-2 
(May 19, 2016). For this reason, DOE concludes that the efficiency of 
the motor alone, even when coupled with the output airflow of the 
compressor, is not an appropriate metric to represent to energy 
efficiency or consumption of an air compressor.
    Alternatively, DOE recognizes that CASTAIR may have been 
recommending a metric of the form of power (in kW) per unit flow (in 
cfm). DOE acknowledges that this general metric could properly 
characterize the typical energy use of an air compressor, if coupled 
with an appropriate test method. However, this ratio has a significant 
shortcoming as a regulatory metric. Specifically, achievable kW/cfm is 
a function of both pressure and flow, which means an energy 
conservation standard would need to be a function of both pressure and 
flow--a more complex determination as compared to package isentropic 
efficiency.\15\ Thus, in this final rule, DOE concludes that a metric 
of the form kW/cfm introduces unnecessary complexity into any energy 
conservation standards that would rely on such a metric (i.e., adding 
pressure as a second dependent characteristic).
---------------------------------------------------------------------------

    \15\ For example, higher flow machines can naturally achieve a 
better kW/cfm score as maximum achievable motor and bare compressor 
efficiency increase with size and flow. Alternatively, lower 
pressure machines can naturally achieve a better kW/cfm score as 
less power is required to compress the same volume of air to a lower 
pressure.
---------------------------------------------------------------------------

    With respect to metric selection, Atlas Copco asserted that DOE's 
method of calculating compressor energy use is flawed because, as a 
steady-state metric, it lacks a means to compare in-operation energy 
savings of compressors with different operating profiles. Atlas Copco 
further asserted that DOE failed to use a methodology to calculate the 
performance of an air compressor at part-load, and failed to take into 
account energy losses due to the cyclic operations. Cyclic operations, 
commented Atlas Copco, are responsible for an additional vast amount of 
energy required without delivering any useful air and should be 
accounted for to understand cyclic demands required for certain 
applications. (Docket No. EERE-2013-BT-STD-0040, Atlas Copco, No. 0054 
at p. 9; Atlas Copco, No. 0009 at pp. 13-14)
    Atlas Copco suggested an alternative metric that considers energy 
consumption during loaded operation, unloaded operation, and the 
transient in-between. Specifically, Atlas Copco suggested a metric that 
calculates the energy consumption for one running hour and the 
accumulated useful volume of air which is delivered to the customer. 
Based on these values, the corresponding overall Specific Energy 
Requirement (SER) can be calculated, which can be converted to the 
isentropic efficiency. Atlas Copco went on to specifically define SER 
as the energy consumed during one hour of operation, divided by the 
useful volume of air produced during this time period, and provided an 
equation to convert SER to isentropic efficiency. Atlas Copco stated 
that these metrics reflect the true energy consumption and would allow 
customers to compare all compressor technologies on an apples-to-apples 
basis. It also stated that such metrics would provide a method to 
assess the part-load performance of variable-speed machines that cannot 
reach the 40-percent load point rather than allowing the compressor to 
test at the minimum achievable flow point, which unfairly penalizes 
large turndown variable-speed compressors. (Atlas Copco, No. 0009 at p. 
12-13; Atlas Copco, No. 0009 at p. 15; Docket No. EERE-2013-BT-STD-
0040, Atlas Copco, No. 0054 at pp. 9-11)
    In its comments, Atlas Copco suggests that the energy consumption 
during one hour of operation can be calculated as the sum of the energy 
consumed during loaded and unloaded operation (which can be measured 
using ISO 1217:2009(E)), as well as the ``cycle energy requirement.'' 
Atlas Copco

[[Page 1069]]

defines the cycle energy requirement as the total energy required for 
fully pressurizing the internals of the compressor package starting 
from idle regime until useful air delivery, summed with the full 
venting of the same internals starting from the end of useful air 
delivery until idle regime; i.e., the energy consumed during transient 
operation between the loaded and unloaded state. Atlas Copco goes on to 
provide a suggested measurement procedure for the determination of 
cycle energy losses. (Atlas Copco, No. 0009 at pp. 13-14; Atlas Copco, 
Annex A, No. 0009 at pp. 3-13; Docket No. EERE-2013-BT-STD-0040, Atlas 
Copco, No. 0054 at p. 9-11) Further, Atlas Copco suggested that DOE 
establish separate regulations for the fixed flow profile and the 
variable flow profile, but to also have all machines list values for 
both. (Atlas Copco, No. 0009 at p. 11; Atlas Copco, No. 0009 at p. 15) 
Given Atlas Copco's suggestion to use a new metric, DOE is unclear what 
values Atlas Copco is referring to when it suggests that DOE list 
``both.'' DOE is unclear whether Atlas Copco supports the use of its 
new metrics (SER and its associated isentropic efficiency) as the 
exclusive metrics for compressors, or if Atlas Copco is suggesting that 
the new metrics be used in addition to the DOE-proposed part-load and 
full-load package isentropic efficiency.
    Sullair agreed that although measurements and efficiency standards 
for part-load operation of fixed-speed compressors may be useful, no 
standard has been established, tested, or proven to measure compressor 
performance across all fixed-speed control methods (modulation, load-
unload, variable displacement, etc.) employed by various manufacturers. 
As a result, Sullair commented that it did not support a part-load test 
procedure for fixed-speed compressors at this time. Sullair noted that 
preliminary work is being done by CAGI to measure one of these control 
methods (variable displacement) and supported further development of a 
test procedure or metric across multiple manufacturers and control 
types prior to adoption by DOE. (Docket No. EERE-2013-BT-STD-0040, 
Sullair, No. 0056 at pp. 16-17)
    Sullair cited that the variable-speed, part-load performance data 
used to develop both the EU Lot 31 draft standard and the proposed DOE 
standard came from CAGI's Performance Verification Program, which was 
gathered over the span of nearly 10 years. In contrast, Sullair argued 
that to rush development of a new test method and metric for part-load 
measurement of fixed-speed compressors, without support from the 
industry or verified supporting data from multiple manufacturers and 
units, would be rash and inappropriate. Sullair anticipated that such a 
development risks unintended consequences that may negatively impact 
the compressor industry, compressor consumers, and U.S. industry at-
large. (Docket No. EERE-2013-BT-STD-0040, Sullair, No. 0056 at pp. 16-
17)
    Sullair concluded that, primarily because of a lack of verified 
data and an agreed upon industry test standard for all fixed-speed 
control types, DOE should proceed with its proposal to classify 
compressors as fixed-speed or variable-speed, and limit part-load 
testing to variable-speed compressors. (Docket No. EERE-2013-BT-STD-
0040, Sullair, No. 0056 at pp. 16-17)
    In agreement with Sullair, DOE acknowledges that a package 
isentropic efficiency metric that includes cycle losses (as recommended 
by Atlas Copco) could acceptably represent the typical energy use of 
compressors. However, as discussed in Sullair's comment, the use of 
cycle losses and the test and calculation methods recommended by Atlas 
Copco represent the opinions and findings of one industry participant, 
and do not represent an industry accepted metric or test method. Atlas 
Copco has not presented evidence that these methods and accompanying 
results have been validated or peer reviewed outside of Atlas Copco's 
organization. Further, DOE believes that the use of Atlas Copco's 
suggested metric and cycle loss test method is likely to increase the 
burden on manufacturers as it appears to require additional testing 
beyond what was proposed in the test procedure NOPR. Furthermore, the 
industry (outside of Atlas Copco) is unfamiliar with the additional 
testing that would be required. Finally, no historical performance data 
exists for the metric proposed by Atlas Copco, which makes it a poor 
choice for a regulatory metric at this time. Without historical 
performance data for the Atlas Copco metric, DOE would be unable to 
establish baseline and maximum technologically feasible efficiency 
levels, and would be unable to complete any of the analyses required to 
assess and establish energy conservation standards.
    Alternatively, given the general support of CAGI, Sullivan-Palatek, 
Ingersoll Rand, and Sullair for items on which they did not directly 
comment on, DOE believes that full-load package isentropic efficiency 
represents an industry-accepted metric, which is backed by an industry-
accepted test method (ISO 1217:2009(E), as amended), and has a large 
cache of reliable industry test data. (CAGI, No. 0010 at p. 3, 
Sullivan-Palatek, No. 0007 at p. 1; Ingersoll Rand, No. 0011 at p. 1; 
Sullair, No. 0006 at p. 1) The use of full-load package isentropic 
efficiency in the EU Lot 31 draft standard further indicates that this 
metric is an appropriate and industry-accepted metric for the 
assessment of fixed-speed compressors. In summary, DOE again 
acknowledges that Atlas Copco's suggested metric, which incorporates 
part-load cycle losses, may acceptably represent the typical energy use 
of compressors, however for the reasons discussed in this section, DOE 
concludes that, at this time, it is not an appropriate metric to adopt. 
If this metric gains acceptance in the industry and the test method can 
be formalized and validated beyond a case study, DOE may consider 
incorporating such a method in future rulemakings.
    With respect to Atlas Copco's suggestion that each compressor be 
labeled with scores from two metrics, DOE notes the core purpose of a 
Federal test procedure is to establish test methods to evaluate 
equipment against the applicable energy conservation standards. If DOE 
were to require the listing of two metrics on each compressor, DOE must 
require that each compressor test to two test methods. Requiring such 
testing and reporting would represent an incremental burden beyond what 
DOE proposed in the test procedure NOPR. In general, DOE strives to 
minimize the incremental burden of any test procedures rulemaking. 
Therefore, in this test procedure final rule, DOE does not adopt any 
mandatory testing or reporting beyond the metrics proposed in the test 
procedure NOPR.
    Similarly to Atlas Copco, the CA IOUs suggested that, for fixed-
speed compressors with either ``start/stop,'' or ``load/unload'' 
controls, the air flow and power consumption should be tested to 
capture energy consumption at full-load and fully unloaded. They also 
suggested that fixed-speed compressors with ``load/unload'' controls be 
tested to measure the duration of the purge cycle (time it takes to 
achieve fully unloaded power--also known as blowdown time), as this 
data can be mathematically combined with the airflow and power 
consumption data at full-load and fully unloaded to estimate the 
compressor's efficiency at various points between full-load and fully 
unloaded. (CA IOUs, No. 0012 at p. 1-2) Unlike Atlas Copco, the CA IOUs 
suggest that this data be measured and reported as supplemental 
information, rather than incorporated into a new metric.

[[Page 1070]]

    While DOE agrees that information describing unloaded and 
transition states of operation could be useful to the end user, the CA 
IOUs' recommendation represents testing and reporting that is not 
essential to the output of the test procedures; requiring such testing 
and reporting would represent an incremental burden beyond what DOE 
proposed in the test procedure NOPR. In general, DOE strives to 
minimize the incremental burden of any test procedures rulemaking. 
Therefore, in this test procedure final rule, DOE is not adopting any 
mandatory testing or reporting of no-load power. Manufacturers may 
measure and advertise no-load power and blowdown time, and DOE may 
further explore no-load power measurement and reporting requirements in 
a future rulemaking.
    CAGI also argued for the importance of considering operating 
conditions in determining efficiency. CAGI commented that, because 
field variables were a large determinant of system efficiency, any 
value assigned to package efficiency may be misleading to consumers. 
(Docket No. EERE-2012-BT-DET-0033, CAGI, No. 0003 at p. 8)
    In response to CAGI's comment, DOE is not representing package 
isentropic efficiency as a substitute for consideration of site-
specific operating factors. Rather, it is intended to serve as a common 
basis for comparison between compressors.
    Atlas Copco suggested that low-pressure air and lubricant-free 
compressors have their package isentropic efficiencies expressed as a 
function of discharge pressure in addition to flow rate, noting that 
full-load operating pressure is a significant variable that affects 
package isentropic efficiency for those compressor configurations. 
(Atlas Copco, No. 0009 at p. 15; Atlas Copco, Public Meeting 
Transcript, No. 0016 at pp. 41-42; EERE-2013-BT-STD-0040, Atlas Copco, 
No. 0054 at pp. 19-20) As discussed in sections III.B, DOE is narrowing 
the scope of this test procedure final rule to a smaller pressure 
range, which only includes lubricated compressors. This revised scope 
matches the range over which the dependency of isentropic efficiency on 
discharge pressure is described by CAGI as limited. Therefore, DOE 
concludes that the changes to the proposed metric, recommended by Atlas 
Copco, are not necessary. However, DOE may consider adding a pressure-
dependent term, should it choose to pursue to test procedures or energy 
conservation standards for lubricant-free equipment or equipment 
outside of the 75-200 psig range in future rulemakings.
    Scales Industrial Technologies agreed that the package isentropic 
efficiency metric is a good measurement, but commented that the metric 
is not common in industry. Scales Industrial Technologies suggested 
instead to use specific power, as it has been the industry-accepted 
expression of compressor efficiency. (Scales Industrial Technologies, 
No. 0013 at p. 4)
    In response, DOE acknowledges that package isentropic efficiency is 
not as commonly used as specific power. However, based on the general 
support of other commenters for package isentropic efficiency, its use 
in the analogous EU Lot 31 draft standard, and its pressure 
independence over the scope being established in this final rule, DOE 
concludes that package isentropic efficiency is the most appropriate 
metric for describing the energy performance of compressors within the 
scope of this test procedure.
b. Load Points Selection and Applicability
    As shown in Equation 1 and Equation 2 in the test procedure NOPR, 
DOE proposed that fixed-speed units be tested at a single load point, 
the full-load actual volume flow rate; and that variable-speed units be 
tested at three load points: 100, 70, and 40 percent of full-load 
actual volume flow rate. 81 FR 27220, 27232-4 (May 5, 2016).
    In response, ASAP and NEEA generally supported DOE's proposed load 
points for full-load and part-load package isentropic efficiency. (ASAP 
and NEEA, No. 0015 at p. 2) Kaeser Compressors also supported the 
selection of load points that harmonized with the EU Lot 31 draft 
standard. (Kaeser Compressors, Public Meeting Transcript, No. 0016 at 
p. 63) Alternatively, the CA IOUs suggested that variable-speed 
compressors be tested at a minimum of six test points (excluding a no 
load power test point), in alignment with the CAGI Performance 
Verification Program test procedure, and also use a minimum volume flow 
rate no higher than 40 percent of the maximum volume flow rate to avoid 
possible loopholes. (CA IOUs, No. 0012 at p. 3)
    With respect to the smallest flow rate load point for variable-
speed compressors, CAGI noted that not all variable-speed compressors 
can reach a speed that achieves 40 percent of full-load actual volume 
flow rate, as minimum speeds can be limited by technical considerations 
such as bearing speeds, overheating, motor current, etc. (CAGI, Public 
Meeting Transcript, No. 0016 at p. 60) Kaeser Compressors and Sullair 
supported CAGI's remark, while Sullair continued to state that this is 
especially important for lubricant-free compressors due to technical 
limitations that keep them from running at speeds as low as 40 percent 
of [full] flow. (Sullair, Public Meeting Transcript, No. 0016 at p. 64) 
Kaeser Compressors added that, among other reasons, EU Lot 31 draft 
standard can set a 40-percent load point because it does not include 
lubricant-free compressors. (Kaeser Compressors, Public Meeting 
Transcript, No. 0016 at pp. 64-5) In response to this concern, CAGI 
suggested that the lower load point should be at 40 percent flow or the 
manufacturer's minimum stated capacity, if greater. (CAGI, No. 0010 at 
p. 6) Sullair supported CAGI's comments. (Sullair, Public Meeting 
Transcript, No. 0016 at p. 64)
    Atlas Copco commented that a provision that permits manufacturers 
to test at the manufacturer's stated minimum speed if a compressor 
cannot achieve the 40-percent load point would penalize compressor 
packages with large turndown ratios. (Atlas Copco, No. 0009 at p. 12-
13) Atlas Copco further clarified that the disadvantage to larger 
turndown machines results from the higher average efficiency achieved 
by testing at a load point greater than 40 percent, which results in a 
higher average weighted isentropic efficiency. (Atlas Copco, Public 
Meeting Transcript, No. 0016 at p. 60) DOE notes in this statement that 
Atlas Copco has incorrectly quoted the test procedure NOPR, in which 
DOE made no mention of how to test a variable-speed compressor for 
which the 40-percent load point is unachievable due to technical 
limitations. Atlas Copco went on to suggest that compressors that 
cannot reach the 40-percent load point should instead be allowed to use 
the SER metric, which is discussed in section III.C.1.a. (Atlas Copco, 
No. 0009 at p. 11) Atlas Copco further commented that the draft EU 
compressor standard included no load power as a reported metric, 
allowing for a more complete picture of efficiency when a variable-
speed compressor is used at flow rates below the manufacturer's minimum 
flow rate. (Atlas Copco, Public Meeting Transcript, No. 0016 at pp. 69-
70)
    Similar to Atlas Copco, Kaeser Compressors noted that there would 
be efficiency gains in testing at flow rates greater than 40 percent, 
but that there would also be market disadvantages because the unit 
would seem less flexible, and so there would be little incentive for 
manufacturers to declare relatively high flow rates. For that reason, 
Kaeser therefore suggested that main issue with the 40-percent load

[[Page 1071]]

point was not the possibility of manufacturers artificially increasing 
efficiency ratings, but instead the fact that lubricant-free 
compressors may not be able to reach that flow rate. (Kaeser 
Compressors, Public Meeting Transcript, No. 0016 at pp. 65-6) Sullair 
stated that manufacturers would lose marketability if they rated the 
unit at a greater minimum flow rate to gain efficiency, because the 
primary benefit of variable-speed compressors is to allow control over 
a wide range of flow rates. (Sullair, Public Meeting Transcript, No. 
0016 at p. 66) Likewise, ASAP, ACEEE, NEEA, NRDC, NEEP, and ASE did not 
support the CAGI proposal of using a lower load point of 40 percent or 
manufacturer minimum as it inflates efficiency ratings for compressors 
that cannot reach 40 percent and suggested that DOE work with CAGI to 
develop an alternative minimum test for compressors. (EERE-2013-BT-STD-
0040, ASAP, ACEEE, NEEA, NRDC, NEEP, ASE, No. 0060 at p. 4)
    In response to comments on the 40-percent load point, DOE reviewed 
all available CAGI Performance Verification Program data sheets for 
lubricant-free variable-speed compressors, and concurs with the 
concerns raised by industry that not all lubricant-free variable-speed 
compressors can achieve the 40-percent load point. Specifically, DOE 
found that 65 percent of CAGI data sheets for lubricant-free 
compressors were rated with a minimum flow greater than 40 percent of 
maximum flow.
    DOE considers this data, in conjunction with the previously 
referenced comments, as clear evidence that the proposed test procedure 
load points do not apply to variable-speed lubricant-free compressors 
due to the technical limitations in the turndown ratio of such 
equipment. Further, DOE concludes that because of these technical 
limitations and other significant technological differences between 
lubricated and lubricant-free compressors, separate test methods and 
metrics may be required for each. In addition, the European Commission 
is exploring specific standards and test methods for lubricant-free 
compressors, but has not released a draft proposal of its standard. 
Based on the comments discussed in this section, DOE concludes that 
significant work is required to establish an acceptable test method 
specific to lubricant-free compressors, and that the most efficient 
path to establishing an acceptable test method for lubricant-free 
compressors is to monitor and, possibly, collaborate with the European 
Commission as its own work progresses. DOE may pursue a test procedure 
for lubricant-free equipment in a separate rulemaking, but is not 
including lubricant-free compressors in the scope of this test 
procedure final rule.
    For lubricated compressors, DOE found that 16 percent of CAGI data 
sheets were rated with a minimum flow greater than 40 percent of 
maximum flow. These results indicate that 84 percent of lubricated 
variable-speed compressors are able to achieve the 40-percent load 
point.
    DOE agrees with Atlas Copco that allowing those few lubricated 
variable-speed compressors that cannot achieve 40 percent flow to test 
using the minimum achievable flow as an alternative to the 40-percent 
load point would penalize high-turndown machines. Such penalization 
would occur because the package isentropic efficiency of a variable-
speed compressor typically decreases as flow (i.e., load) decreases. To 
confirm this, DOE reviewed available CAGI Performance Verification 
Program data sheets and found that for 82 percent of the rotary 
lubricated variable-speed models, the package isentropic efficiency at 
40 percent of full-load actual volume flow rate was lower than the 
package isentropic efficiency at 70 percent of full-load actual volume 
flow rate.\16\ Given this relationship between package isentropic 
efficiency and flow rate, a compressor's package isentropic efficiency 
(as proposed in the test procedure NOPR) would typically increase by 
replacing the 40-percent load point with a load point at a higher flow.
---------------------------------------------------------------------------

    \16\ Not all units reported performance at 40 percent and 70 
percent of full-load actual volume flow rate. In those cases, DOE 
generated estimates for those points using interpolation from 
surrounding data points.
---------------------------------------------------------------------------

    Given this information, DOE has two major concerns with CAGI's 
recommendation. First, CAGI's recommended method would not result in a 
fair and equitable efficiency metric. For example, given two 
compressors with the same full-load actual volume flow rate and full-
load package isentropic efficiency, one with a manufacturer-specified 
minimum flow rate of 40 percent of full-load actual volume flow rate 
and one with a manufacturer-specified minimum flow rate of 70 percent 
of full-load actual volume flow rate, the latter would usually test at 
a better part-load package isentropic efficiency, even though the 
former provides more utility to the end user and has the potential to 
use less energy.
    Second, CAGI's recommended method relies on a ``manufacturer's 
minimum stated capacity,'' and creates a significant opportunity for 
loopholes. For example, if a given variable-speed compressor does not 
meet the established energy conservation standard, a manufacturer may 
be able to restate its minimum capacity at a larger value and retest 
the model. Because package isentropic efficiency is typically greater 
at the rerated higher capacity, the manufacturer may be able to pass 
the standard with the rerated value. The result of this example 
directly conflicts with the intent of an energy conservation standard, 
because the resulting compressor offers reduced utility to the end user 
and may even consume more energy than it would with a lower stated 
minimum capacity.
    Consequently, in this final rule, DOE rejects CAGI's recommendation 
to use the manufacturer's minimum stated capacity for variable-speed 
compressors if the compressor cannot achieve the 40-percent load point.
    DOE concludes that the amount to which a variable-speed lubricated 
compressor can turn down is a distinct end user utility. Both Sullair 
and Kaeser Compressors clearly noted similar assertions that the speed 
and flow to which a variable-speed compressor can turn down is a 
distinct utility to the end user. (Sullair, Public Meeting Transcript, 
No. 0016 at p. 66; Kaeser Compressors, Public Meeting Transcript, No. 
0016 at pp. 65-6)
    DOE also concludes, based on previously mentioned data analysis as 
well as comments from Kaeser Compressors and Sullair (Sullair, Public 
Meeting Transcript, No. 0016 at p. 67; Kaeser Compressors, Public 
Meeting Transcript, No. 0016 at pp. 67-8), that for lubricated 
variable-speed compressors within the scope of this final rule, the 
majority of lubricated compressors are able to reach the 40-percent 
load point; i.e., turning down to 40 percent of flow is technologically 
feasible for all pressures, flows, and horsepower of compressors within 
the scope of this final rule.
    Consequently, DOE concludes that it is appropriate that the test 
method for variable-speed lubricated compressors require that a tested 
compressor reach each flow point because the part-load package 
isentropic efficiency metric is designed to align with the utility of 
the variable-speed compressors and must accurately represent their 
operation. For these reasons, DOE is adopting the methodology as 
proposed in the NOPR, which requires testing at the 40-percent load 
point. If a manufacturer has a basic model which is incapable of 
operating at the 40-percent load point, the manufacturer must seek a 
waiver from

[[Page 1072]]

the test procedure to obtain an alternative method of test from the 
Department pursuant to 10 CFR 431.401. As part of the test procedure 
waiver application, DOE would examine the details of the variable-speed 
compressor's performance curve (e.g., the package isentropic efficiency 
over the range of available driver speeds for which the compressor is 
capable of operating) in order to determine the correct testing points 
and weightings for regulatory purposes. Since these could be different 
for each basic model, DOE believes it is best to determine the details 
on a basic model basis, rather than adopting a blanket approach of the 
manufacturer's specified minimum as suggested by CAGI. This would allow 
DOE to ensure fair and equitable ratings and not disadvantage those 
compressors that operate at lower speeds. This approach ensures that 
all compressors rated with the part-load package isentropic efficiency 
metric provide comparable utility to the end user, and that any 
compressors requiring a waiver would use a modified metric that 
reflects the reduction in utility resulting from their restricted range 
of flow rates.
    DOE's regulations set forth at 10 CFR 431.401 contain provisions 
that permit a person to seek a waiver from the test procedure 
requirements for covered equipment if at least one of the following 
conditions is met: (1) The basic model contains one or more design 
characteristics that prevent testing according to the prescribed test 
procedures; or (2) the prescribed test procedures may evaluate the 
basic model in a manner so unrepresentative of its true energy 
consumption as to provide materially inaccurate comparative data. 10 
CFR 431.401(a)(1) A petitioner must include in its petition any 
alternate test procedures known to the petitioner to evaluate the basic 
model in a manner representative of its energy consumption. 10 CFR 
431.401(b)(1)(iii) DOE may grant a waiver subject to conditions, 
including adherence to alternate test procedures. 10 CFR 431.401(f)(2)
    For the case of variable-speed compressors that cannot reduce flow 
to the 40-percent load point, DOE may grant a waiver using a modified 
test procedure that reflects the reduction in utility resulting from 
the compressor's restricted range of flow rates. The modified test 
procedure may calculate part-load package isentropic efficiency using a 
weighted average of the performance at full-load, the performance at 
the 70-percent load point (if the compressor can reach this load 
point), and the performance at the compressor's lowest load point. The 
weighted average may include modifications to reflect the reduction in 
utility resulting from the compressor's restricted range of flow rates. 
For example, the weighting may consider the typical change of 
efficiency with flow rate and may account for the increased energy 
required for the compressor to achieve the 70-percent and 40-percent 
load points by loading and unloading. DOE may determine the modified 
test procedure on a case-by-case basis, depending on the specific 
nature of the waiver request and the equipment construction.
    Based on the preceding discussion, DOE concludes that no changes 
are needed in DOE's proposed definitions of fixed-speed compressor and 
variable-speed compressor. As a result, DOE is adopting the definitions 
of fixed-speed compressor and variable-speed compressor that it 
proposed in the test procedure NOPR.
    With respect to the remaining load points (i.e., 100 and 70 percent 
for variable-speed and 100 percent for fixed-speed), DOE reiterates 
that Kaeser Compressors, ASAP, and NEEA supported DOE's test procedure 
NOPR. (Kaeser Compressors, Public Meeting Transcript, No. 0016 at p. 
63; ASAP and NEEA, No. 0015 at p. 2) However, the CA IOUs disagreed and 
suggested that variable-speed compressors be tested at a minimum of six 
test points while utilizing a minimum volume flow rate no higher than 
40 percent of the maximum volume flow rate to avoid possible loopholes. 
In response, DOE recognizes that the CA IOUs' recommendation aligns 
with the current CAGI Performance Verification Program testing method; 
however, DOE has two major concerns with CA IOUs' recommendation. 
First, the CA IOUs' recommended method would not result in a 
repeatable, fair, and equitable efficiency metric. For example, given 
two compressors with the same full-load actual volume flow rate and 
full-load package isentropic efficiency, one could be tested at six 
points (40, 50, 60, 70, 80, and 100 percent of full-load actual volume 
flow rate) and one could be tested at 10 points (40, 50, 60, 70, 80, 
90, 92.5, 95, 97.5, and 100 percent of full-load actual volume flow 
rate). As previously discussed, due to the fact that package isentropic 
efficiency varies as a function of actual volume flow rate, the latter 
compressor, tested at 10 load points would likely achieve a different 
part-load package isentropic efficiency score (as in the test procedure 
NOPR) than the former compressor.
    Similarly, the lack of firmly specified load points creates a 
significant opportunity for loopholes. For example, if a given 
variable-speed compressor does not meet the established energy 
conservation standard, a manufacturer may be able to retest with 
additional load points that are biased to the compressor's most 
efficient flow range and ultimately pass the standard with this rerated 
value. This directly conflicts with the intent of an energy 
conservation standard, as the resulting compressor still consumes the 
same amount of energy as it did before the retesting and rerating.
    Due to these concerns with the CA IOUs' suggestion, the general 
support provided by CAGI, ASAP, and NEEA, and the reasons established 
in the test procedure NOPR, DOE is adopting the load points of 100, 70, 
and 40 percent of full-load actual volume flow rate for the part-load 
package isentropic efficiency metric, and 100 percent of full-load 
actual volume flow rate for the full-load package isentropic efficiency 
metric.
c. Metric Applicability
    In response to the test procedure NOPR, the CA IOUs suggested that 
fixed-speed ``inlet modulating'' \17\ and ``variable displacement'' 
\18\ compressors (herein referred to as ``fixed-speed variable-flow 
compressors'') should be tested at full-load and multiple part-loads in 
alignment with the CAGI Performance Verification Program test 
procedures for variable-speed compressors. According to the CA IOUs, 
this would provide valuable efficiency information for part-load 
conditions, which are common for fixed-speed compressors. (CA IOUs, No. 
0012 at pp. 2) Similarly, ASAP and NEEA suggested that DOE require that 
fixed-speed compressors with controls that allow for variable airflows 
be tested in the same way as variable-speed compressors. ASAP and NEEA 
stated that this would facilitate the comparison between fixed-speed 
and variable-speed compressors

[[Page 1073]]

under part-load conditions. (ASAP and NEEA, No. 0015 at p. 2)
---------------------------------------------------------------------------

    \17\ Inlet modulating compressors adjust the capacity of the 
compressor to the demand required by the system with a regulating 
valve on the inlet. The control system closes the inlet valve in 
response to a reduction in system demand, effectively throttling the 
compressor by reducing the inlet pressure and, consequently, the 
mass flow of air entering the compressor. (https://www.cagi.org/requestinator_dl.aspx?txdata=L3BkZnMvQ0FHSV9FbGVjdEhCX2NoMi5wZGY=, 
page 88).
    \18\ Variable displacement compressors use a valve to divert a 
fraction of the inlet mass flow from the start of the rotor to an 
intermediate position of the compression system, reducing the 
effective length of the rotor but maintaining the inlet pressure and 
compression ratio. The valve is adjustable and responds to changes 
in discharge pressure. (https://www.cagi.org/requestinator_dl.aspx?txdata=L3BkZnMvQ0FHSV9FbGVjdEhCX2NoMi5wZGY=, 
page 88).
---------------------------------------------------------------------------

    NEEA further commented that the efficiency metrics are appropriate 
for comparing variable-speed compressors amongst themselves, but made 
it hard to compare variable-speed compressors to fixed-speed 
compressors. (NEEA, Public Meeting Transcript, No. 0016 at p. 60-62) 
Conversely, Sullivan-Palatek commented that fixed-speed and variable-
speed compressors are different products with different applications, 
which shouldn't be compared with each other. (Sullivan-Palatek, Public 
Meeting Transcript, No. 0016 at pp. 61-62)
    Kaeser Compressors commented that the efficiency and utility of a 
variable-speed compressor relative to a fixed-speed compressor is 
promoted by utilities to consumers and stressed that the primary goal 
of the metric should be consistent assessment of variable-speed 
compressor efficiency. (Kaeser Compressors, Public Meeting Transcript, 
No. 0016 at pp. 71-72) Sullair echoed this sentiment, stating that the 
industrial customers that purchase the equipment understand the energy 
efficiency associated with variable-speed compressors and purchase 
variable-speed compressors based on the best overall fit for the 
application. (Sullair, Public Meeting Transcript, No. 0016 at p. 72)
    Sullair agreed that although measurements and efficiency standards 
for part-load operation of fixed-speed compressors may be useful, no 
standard has been established, tested or proven to measure compressor 
performance across all fixed-speed control methods (modulation, load-
unload, variable displacement, etc.) employed by various manufacturers. 
As a result, Sullair commented that it did not support a part-load test 
procedure for fixed-speed compressors at this time. Sullair noted that 
preliminary work is being done by CAGI to measure one of these control 
methods (variable displacement) and supported further development of a 
test procedure or metric across multiple manufacturers and control 
types prior to adoption by DOE. (Docket No. EERE-2013-BT-STD-0040, 
Sullair, No. 0056 at pp. 16-17)
    In agreement with the CA IOUs, ASAP, NEEA, and Sullair, DOE 
acknowledges that a part-load package isentropic efficiency metric for 
fixed-speed variable airflow compressors could acceptably represent the 
typical energy use of these compressors. DOE reviewed the scope and 
applicability of relevant, comparable testing and rating programs, 
namely, the CAGI Performance Verification Program and the EU Lot 31 
draft standard for compressors. The CAGI Performance Verification 
Program separates rotary compressors into only two groupings: (1) 
``rotary compressors,'' and (2) ``rotary variable frequency drive 
compressors.'' \19\ The former rates compressors at only full-load 
operating pressure, while the latter allows for multiple ratings at 
reduced flows. However, as indicated by the name of the latter 
grouping, it encompasses only compressors driven by variable-frequency 
drives. Consequently, fixed-speed variable airflow compressors are 
considered ``rotary compressors'' by the CAGI Performance Verification 
Program, and rated at only full-load operating pressure.
---------------------------------------------------------------------------

    \19\ For more information see: https://www.cagi.org/performance-verification/data-sheets.aspx.
---------------------------------------------------------------------------

    In addition, the EU Lot 31 draft standard defines a ``fixed-speed 
rotary standard air compressor'' to mean a rotary standard air 
compressor that is not equipped with a variable-speed drive when placed 
on the market; and defines a ``variable-speed rotary standard air 
compressor'' to mean a rotary standard air compressor that is equipped 
with a variable-speed drive when placed on the market. Consequently, 
similar to the CAGI program, the EU Lot 31 draft standard considers a 
fixed-speed variable airflow compressor to be a fixed-speed rotary 
standard air compressor, which is rated at only full-load operating 
pressure.
    As a result of the research into relevant, comparable testing and 
rating programs for compressors, DOE agrees with Sullair that test 
methods for variable airflow fixed-speed compressors are still in the 
development stage and the limited available data is not yet fully 
verified. In other words, test methods are still a work in progress for 
this variety of fixed-speed compressors. Additionally, with no 
historical part-load performance data available for variable-flow 
fixed-speed compressors, DOE would be unable to establish baseline and 
maximum technologically feasible efficiency levels, and would be unable 
to complete any of the analyses required to assess and establish energy 
conservation standards. Alternatively, historical full-load isentropic 
efficiency currently exists for this equipment and was considered in 
the energy conservation standards NOPR.
    In light of the precedent established by CAGI and the EU, the lack 
of a verified test method, and the lack of verified historical 
performance data, DOE concludes that it is not appropriate to establish 
part-load package isentropic efficiency as the rating metric for non-
speed-varying varieties of variable airflow compressors at this time. 
Consequently, in this final rule, DOE reaffirms and establishes its 
NOPR test procedure that when rating a compressor for compliance 
purposes, full-load package isentropic efficiency applies to fixed-
speed compressors, and part-load package isentropic efficiency applies 
to variable-speed compressors.
    Although part-load package isentropic efficiency is not currently 
suitable as a regulatory metric for fixed-speed variable flow 
compressors, part-load performance information for these varieties of 
compressors can provide valuable information for the end user. 
Consequently, in this final rule DOE clarifies that manufacturers of 
fixed- and variable-speed compressors may continue making graphical or 
numerical representations of package isentropic efficiency and package 
specific power as functions of flow rate or rotational speed. In the 
test procedure NOPR, DOE proposed a similar allowance, applicable only 
to variable-speed compressors. 81 FR 27220, 27244 (May 5, 2016). DOE is 
opening this allowance to fixed-speed compressors to account for non-
speed-varying varieties of variable airflow compressors and fixed-speed 
compressors that can vary speed continuously to adjust output flow, but 
cannot reach 40 percent of full-load actual volume flow rate.
    DOE notes that graphical or numerical representations of package 
isentropic efficiency or package specific power at 40, 70, and 100 
percent of the full-load actual volume flow rate must represent values 
measured in accordance with the DOE test procedure. DOE also notes that 
graphical or numerical representations of these metrics at any other 
load points must be generated using methods consistent with the DOE 
test procedure.
d. Metric Weights
    In the test procedure NOPR, DOE proposed a part-load package 
isentropic efficiency metric that was a weighted composite of 
performance at multiple load points, following the structure of the EU 
Lot 31 draft standard. 81 FR 27220, 27233 (May 5, 2016). DOE further 
proposed weighting factors of 25, 50, and 25 percent for load points of 
40, 70, and 100 percent of maximum flow, respectively. DOE cited 
alignment with the EU Lot 31 draft standard and a lack of industry 
weighting factors or real-world load profile data as rationale for the 
proposed weights. 81 FR 27220, 27234-5 (May 5, 2016).
    In response to the proposed weights, P.R. China commented that 
there was no selection criteria provided to justify the weighting 
coefficients for the 40

[[Page 1074]]

percent, 70 percent, and 100 percent package isentropic efficiency 
values. (P.R. China, No. 0049 at p. 3) CAGI did not provide any direct 
comments, but CAGI commented that it was in agreement with DOE's 
proposal for items on which it did not directly comment. (CAGI, No. 
0010, p. 3) Ingersoll Rand, Sullair, and Sullivan-Palatek supported 
CAGI's comments. (Ingersoll Rand, No. 0011 at p. 1; Sullair, No. 0006 
at p. 1; Sullivan-Palatek, No. 0007 at p. 1)
    In response to comments made by P.R. China regarding the 
justification of selected load weights, the part-load package 
isentropic efficiency metric is a benchmark for all variable-speed 
compressors. The benchmark's intent is not to mirror energy consumption 
for all consumers (which is calculated in the energy conversation 
standard), but to provide a consistent and repeatable measure of 
efficiency for variable-speed compressors. In this case, half of the 
weighting represents operating extremes (40 percent and 100 percent) 
for variable-speed compressors, and half characterizes the midpoint of 
those values (i.e., 70 percent). Furthermore, DOE did not receive any 
data providing real-world representative load profile data. However, 
even in the presence of such data any given weighting would only 
reflect energy consumption for units that happened to be operated at 
that particular load profile. Additionally, the selected weights are in 
alignment with the EU Lot 31 draft standard, which carries the benefits 
of familiarity for consumers and reduced compliance burden for 
manufacturers who do business in both the US and EU markets. For these 
reasons, as well as those discussed in the test procedure NOPR, DOE is 
adopting the metric weights, as proposed.
2. Package Specific Power
    In the May 5, 2016 test procedure NOPR, DOE defined ``package 
specific power'' to mean the compressor power input at a given load 
point, divided by the actual volume flow rate at the same load point, 
as determined in accordance with the test procedures proposed for 10 
CFR 431.344. 81 FR 27220, 27256 (May 5, 2016). DOE noted that package 
specific power provides users with a direct way to calculate the power 
required to deliver a particular flow rate of air. The CAGI Performance 
Verification Program currently uses this metric to characterize 
compressor performance.\20\ Given the prevalence of this metric in the 
industry, DOE deems it appropriate to provide a clear and uniform 
method to test and calculate this value. However, given the reasons 
noted in the test procedure NOPR, DOE selected package isentropic 
efficiency, rather than package specific power, as the rating metric 
for the compressors within the scope of this rulemaking.
---------------------------------------------------------------------------

    \20\ https://cagi.org/performance-verification/overview.aspx.
---------------------------------------------------------------------------

    For the reasons established in the test procedure NOPR, DOE is 
adopting the definition for package specific power, as proposed in the 
test procedure NOPR.
    The specific methods and calculations used to find package specific 
power for a given compressor are discussed in section III.E.7.
3. Power Factor
    In the test procedure NOPR, DOE did not explicitly propose 
measurement and reporting of power factor. In response, the CA IOUs 
commented that the test procedure NOPR proposed measurement of real 
power (e.g., kW), cannot accurately reflect power generation needs. The 
CA IOUs added that measurement and reporting of power factor should be 
mandatory at all tested points so that power generation needs can be 
accurately estimated. (CA IOUs, No. 0012 at p. 3)
    DOE agrees with the CA IOUs that power factor is a useful metric 
for estimating power generation needs. ISO 1217:2009(E), as 
amended,\21\ allows two methods to determine packaged compressor power 
input, as discussed in section III.E.1.a. One of the allowable methods 
requires measurement of power factor as an intermediary to calculate 
packaged compressor power input. Because only one of the two allowable 
methods requires measurement of power factor, a mandatory reporting 
requirement for power factor would represent an incremental testing 
burden, beyond what DOE proposed in the test procedure NOPR, for some 
manufacturers. As such, there is not enough benefit to the end user to 
justify adopting mandatory measurement and reporting of power factor in 
this final rule. DOE may further explore power factor measurement and 
reporting requirements in future rulemakings.
---------------------------------------------------------------------------

    \21\ In this final rule, DOE is incorporating by reference parts 
of ISO 1217:2009(E) as amended by Amendment 1:2016. Amendment 1:2016 
did not introduce any changes in regards to this particular topic.
---------------------------------------------------------------------------

D. Incorporation by Reference of Industry Standard(s)

    In the test procedure NOPR, DOE stated that ISO 1217:2009(E) is an 
appropriate industry testing standard for evaluating the performance of 
applicable compressors, but noted that some sections of that standard 
were not applicable to the DOE test procedures. DOE further noted that 
additions and modifications to the test method described in ISO 
1217:2009(E) would be necessary in order to determine the package 
isentropic efficiency of applicable compressors and improve 
repeatability and reproducibility of the ratings. Consequently, in the 
test procedure NOPR DOE proposed to incorporate by reference ISO 
1217:2009(E) with a number of modifications. 81 FR 27220, 27236-27243 
(May 5, 2016).
    Specifically, DOE proposed to incorporate by reference the 
following sections and subsections of ISO 1217:2009(E):
     Sections 2, 3, and 4;
     Subsections 5.2, 5.3, 5.4, 5.6, 5.9, 6.2(g), 6.2(h); and
     Subsections C.1.1, C.2.2, C.2.3, C.2.4, C.4.1, C.4.2.1, 
C.4.2.3, C.4.3.2, C.4.4 of Annex C. 81 FR 27220, 27238 (May 5, 2016).
    Conversely, in the test procedure NOPR, DOE proposed not to 
incorporate by reference the following sections, subsections and 
annexes of ISO 1217:2009(E) because they are not applicable to DOE's 
regulatory framework:
     Sections 1, 7, 8 and 9, in their entirety;
     Section 6, (except subsections 6.2(g), and 6.2(h), which 
would be incorporated by reference);
     Subsections 5.1, 5.5, 5.7, and 5.8;
     Annexes A, B, D, E, F, and G in their entirety; and
     Sections C.1.2, C.2.1, C.3, C.4.2.2, C.4.3.1 and C.4.5 of 
Annex C. 81 FR 27220, 27237 (May 5, 2016).
1. ISO 1217:2009(E)/Amd.1:2016
    On April 15, 2016, ISO published an amendment to ISO 1217:2009(E) 
(ISO 1217:2009(E)/Amd.1:2016). In general, amendments to ISO standards 
play the role of materially altering and/or adding content to the 
source document; in this case, ISO 1217:2009(E). ISO 1217:2009(E)/
Amd.1:2016 modifies the definitions of isentropic power and isentropic 
efficiency contained in sections 3.5.1 and 3.6.1 of ISO 1217:2009(E) to 
provide more detail, and provides equations to calculate those 
performance metrics in a new Annex H to ISO 1217:2009(E). ISO 
1217:2009(E)/Amd.1:2016 makes no other changes to ISO 1217:2009(E). In 
this final rule, the combined result of the pre-amendment ISO 
1217:2009(E) and ISO 1217:2009(E)/Amd.1:2016 is referred to as ``ISO 
1217:2009(E), as amended.'' Where the pre-amendment

[[Page 1075]]

version is being referenced, it is referred to simply as ``ISO 
1217:2009(E).''
    Generally, DOE prefers to incorporate the most recent versions of 
industry standards, when such versions remain applicable to its test 
procedures. DOE reiterates that ISO 1217:2009(E)/Amd.1:2016 makes no 
other changes to ISO 1217:2009(E), beyond amending sections 3.5.1 and 
3.6.1 and adding Annex H. Thus, for administrative consistency, in this 
final rule, any sections incorporated by reference in this final rule 
refer to the ISO 1217:2009(E) as amended, rather than the original ISO 
1217:2009(E), as proposed in the test procedure NOPR. The following 
paragraphs discuss rationale for incorporating the amended sections 
3.5.1 and 3.6.1, as well as certain sections of the new Annex H of ISO 
1217:2009(E), as amended.
    In the test procedure NOPR, DOE provided equations to calculate 
isentropic power and package isentropic efficiency, as these equations 
were not present in ISO 1217:2009(E). The equations proposed in the 
test procedure NOPR are mathematically equivalent to those provided in 
the amended version of ISO 1217:2009(E) and could be used in the DOE 
test procedure with no impact on the calculated results. Thus, in this 
final rule, DOE is revising its proposed test procedure to incorporate 
by reference sections 3.5.1 and 3.6.1, as well as sections H.2 and H.3 
of Annex H of ISO 1217:2009(E), as amended. These sections provide the 
symbols, subscripts, and equations needed to calculate isentropic power 
(and ultimately, package isentropic efficiency). Given that the 
equations found in ISO 1217:2009(E), as amended, are mathematically 
equivalent to those proposed by DOE in the test procedure NOPR, DOE 
concludes that this change is administrative in nature. An in-depth 
discussion of the calculations contained in these sections can be found 
in section III.E.5.
    DOE is not incorporating the new sections H.1, H.4, and H.5 of 
Annex H to ISO 1214:2009, as amended, as these sections are not 
applicable to test method in the test procedure NOPR. Specifically, 
subsection H.1 provides a general introduction to Annex H, which is not 
necessary for the application of the symbols, subscripts, and equations 
in subsections H.2 and H.3 for the purposes of the calculation of 
isentropic power. Subsection H.4 provides a derivation of the 
relationship between isentropic efficiency and specific energy 
requirement. While the DOE test procedure adopted today requires the 
calculation of package isentropic efficiency and specific energy (also 
referred to as specific power), it does not require derivation of the 
relationship between these two metrics.\22\ Subsection H.5 provides the 
relationship between customer acceptance tolerances for specific energy 
and isentropic efficiency. Customer acceptance tolerances are not 
directly applicable to, or necessary for DOE's test methods, as DOE is 
establishing its own sampling, representations, and enforcement 
provisions, as discussed in sections III.G and III.H.
---------------------------------------------------------------------------

    \22\ For details on the calculation of package isentropic 
efficiency and specific power, see sections III.E.5 and III.E.7, 
respectively.
---------------------------------------------------------------------------

2. Comments Related to the Incorporation of ISO 1217:2009(E)
    In response to DOE's proposal to incorporate specific sections of 
ISO 1217:2009(E), commenters generally supported incorporating the test 
methods established in ISO 1217:2009(E). ASAP and NEEA commented that 
they support DOE's use of ISO 1217, with the modifications described in 
the test procedure NOPR, as the basis for the compressors test 
procedure. (ASAP and NEEA, No. 0015 at p. 2) Sullair strongly supported 
the use of ISO 1217:2009(E) as the basis for the DOE test procedure. 
(Sullair, No. 0006 at p. 1) Sullivan-Palatek advised against material 
deviations from the test procedure in ISO 1217:2009(E), so as to not 
invalidate previous performance data. (Sullivan-Palatek, No. 0007 at p. 
3) CAGI urged DOE to formalize the incorporation of the ISO 
1217:2009(E) test method so that the historical performance data 
obtained with that test method is compliant with the DOE test 
procedure. (CAGI, No. 0010 at p. 15)
    Compressed Air Systems and Jenny Products dissented from the other 
commenters. Jenny Products objected to incorporating standards by 
reference and advocated for including the referenced sections directly 
in the text of the test procedure to avoid confusion. (Jenny Products, 
No. 0020 at p. 2) Compressed Air Systems suggested caution when 
adopting ISO standards, stating that standards adopted in the United 
States should favor U.S. manufacturing. (Compressed Air Systems, No. 
0008 at p. 2) In response to Compressed Air Systems, DOE clarifies that 
any test procedures adopted by DOE must be fair and equitable to all 
industry participants, regardless of the location that equipment is 
manufactured.
    In response to comments from Compressed Air Systems and Jenny 
Products about incorporating standards directly into the test procedure 
text, DOE is not allowed, due to copyright law, to print any material 
incorporated by reference into the Federal Register or Code of Federal 
Regulations. As a result, when DOE adopts portions of a test procedure 
from ISO, it must incorporate those sections by reference and refer to 
them appropriately in the test procedure. Once the regulation 
publishes, any standard incorporated by reference is incorporated based 
on the date of its publication and is not subject to change. In other 
words, if the external standard is revised in the future, DOE will 
continue to incorporate the prior version in this final rule.
    In addition to general comments, DOE received comments pertinent to 
the specific sections of ISO 1217:2009(E) that DOE proposed to exclude 
or incorporate by reference in the test procedure NOPR. The following 
paragraphs summarize the sections of ISO 1217:2009(E) on which DOE 
received comment, summarize DOE's conclusions, and provide reference to 
the appropriate subsections of section III.E (test method), where these 
comments are addressed in detail.
    DOE received specific comments regarding subsection 5.2 of ISO 
1217:2009(E); these comments are presented and discussed in detail in 
section III.E.1.b. In response, DOE is adopting its proposal to 
incorporate all of subsection 5.2 of ISO 1217:2009(E), as amended, in 
this final rule.
    DOE received comments suggesting that it reconsider subsections 
6.2(i), 6.2(j) and 6.2(k) of ISO 1217:2009(E), with regard to the data 
acquisition requirements. DOE also received suggestions to incorporate 
requirements from Table 1 of ISO 1217:2009(E). (CAGI, No. 0010 at pp. 
6-8, 10; CAGI, Public Meeting Transcript, No. 0016 at pp. 74, 83) (See 
also section III.E.4). In response, DOE decided to incorporate Table 1 
by reference but not to incorporate sections 6.2(i), 6.2(j) and 6.2(k) 
by reference, as discussed in section III.E.4.
    DOE received no specific comment on the other sections of ISO 
1217:2009(E), other than the previously referenced comments expressing 
general support for the use of ISO 1217:2009(E). Thus, for the reasons 
discussed in this document and the test procedure NOPR, DOE 
incorporates the following sections of ISO 1217:2009(E), as amended, by 
reference, in this final rule:
     Sections 2, 3, and 4;
     Subsections 5.2, 5.3, 5.4, 5.6, 5.9, 6.2(g), 6.2(h); and

[[Page 1076]]

     Subsections C.1.1, C.2.2, C.2.3, C.2.4, C.4.1, C.4.2.1, 
C.4.2.3, C.4.3.2, C.4.4 of Annex C.
     Subsections H.2 and H.3 of Annex H.
     Table 1 of subsection 6.2.
    Conversely, in this final rule DOE does not incorporate by 
reference the following sections of ISO 1217:2009(E), as amended:
     Sections 1, 7, 8 and 9, in their entirety;
     Section 6, (except subsections 6.2(g), and 6.2(h), which 
would be incorporated by reference);
     Subsections 5.1, 5.5, 5.7, and 5.8;
     Annexes A, B, D, E, F, and G in their entirety; and
     Sections C.1.2, C.2.1, C.3, C.4.2.2, C.4.3.1 and C.4.5 of 
Annex C.
     Subsections H.1, H.4 and H.5 of Annex H.

E. Test Method

    In the test procedure NOPR, DOE proposed specific test methods to 
measure inlet pressure, discharge pressure, actual volume flow rate, 
and electrical input power. DOE also proposed specific methods to 
calculate package isentropic efficiency, package specific power, 
pressure ratio, full-load actual volume flow rate, full-load operating 
pressure, and maximum full-flow operating pressure. Many of the test 
methods and calculations proposed in the test procedure NOPR were 
incorporated by reference from ISO 1217:2009(E). However, DOE proposed 
several modifications and additions to the methods specified by ISO 
1217:2009(E), as these are required to provide the necessary 
specificity and repeatability. Even with the proposed modifications and 
additions, DOE stated in the test procedure NOPR that its intent was to 
propose a test procedure that would remain closely aligned with 
existing and widely used industry procedures to limit testing burden on 
manufacturers.
    DOE received many specific comments in response to the testing and 
calculation methods proposed in the test procedure NOPR, and one 
general comment from Jenny Products. The following sections walk 
through the methods in the test procedure NOPR, the interested party 
comments as they pertain to the section, and the methods DOE ultimately 
is adopting in this final rule.
    Jenny Products made a general comment that the proposed test 
procedure had measurement equipment and test condition tolerances that 
were too tight for an initial DOE test procedure. Jenny Products 
suggested that relaxing the tolerances initially would reduce the 
burden of the test procedure from a compliance and financial 
standpoint, and that DOE could tighten the tolerances after 
manufacturers are comfortable with the test procedure. (Jenny Products, 
No. 0020 at p. 2)
    DOE acknowledges the comment made by Jenny Products; however, DOE 
reiterates that the goal of the proposed test procedure was to align 
with ISO 1217:2009(E), as amended,\23\ to reduce the burden and cost to 
manufacturers. Most manufacturers currently use ISO 1217:2009(E), and 
many of the testing- and calculation-related comments that DOE received 
suggested that DOE align its test procedure as closely as possible with 
ISO 1217:2009(E). As discussed in the following sections, in this final 
rule, DOE is modifying certain methods proposed in the test procedure 
NOPR, including the tolerances, in order to align as closely as 
possible to ISO 1217:2009(E), as amended.\24\ With these modifications, 
the test methods established in this final rule are intended to produce 
results equivalent to those produced historically under ISO 
1217:2009(E). Consequently, if historical test data meets the 
requirements of the test methods established in this final rule, then 
manufacturers may use this data for the purposes of representing any 
metrics subject to representations requirements. Therefore, because the 
industry-standard test method is ISO 1217:2009(E), DOE is using the 
tolerances specified in ISO 1217:2009(E), and DOE is not relaxing the 
tolerances as suggested by Jenny Products. DOE is also adopting 
additional tolerances that are not specified in ISO 1217:2009(E), and 
the reasoning for each of these tolerances is explained in the 
following sections.
---------------------------------------------------------------------------

    \23\ In this final rule, DOE is incorporating by reference parts 
of ISO 1217:2009(E) as amended by Amendment 1:2016. Amendment 1:2016 
did not introduce any changes in regards to this particular topic, 
so aligning with ISO 1217:2009(E), as amended, is equivalent to 
aligning with ISO 1217:2009(E) prior to Amendment 1:2016.
    \24\ In this final rule, DOE is incorporating by reference parts 
of ISO 1217:2009(E) as amended by Amendment 1:2016. Amendment 1:2016 
did not introduce any changes in regards to this particular topic, 
so aligning with ISO 1217:2009(E), as amended, is equivalent to 
aligning with ISO 1217:2009(E) prior to Amendment 1:2016.
---------------------------------------------------------------------------

1. Measurement Equipment
    In the test procedure NOPR, DOE proposed that for the purposes of 
measuring air compressor performance, the equipment necessary to 
measure flow rate, inlet and discharge pressure, temperature, 
condensate, and energy must comply with the equipment and accuracy 
requirements specified in ISO 1217:2009(E) sections 5.2, 5.3, 5.4, 5.6, 
5.9, C.2.3, and C.2.4 of Annex C. 81 FR 27220, 27237-8 (May 5, 2016). 
DOE also proposed the following specific additions:
     Electrical measurement equipment must be capable of 
measuring true root mean square (RMS) current, true RMS voltage, and 
real power up to the 40th harmonic of fundamental supply source 
frequency. 81 FR 27220, 27240 (May 5, 2016).
     Any instruments used to measure a particular parameter 
must have a combined accuracy of 2.0 percent of the 
measured value at the fundamental supply source frequency, where 
combined accuracy is the sum of the individual accuracies in 
quadrature. 81 FR 27220, 27240 (May 5, 2016).
     Any instruments used to measure the density of air must 
have an accuracy of 1.0 percent of the measured value. 81 
FR 27220, 27241 (May 5, 2016).
     Any pressure measurement equipment used in a calculation 
of another variable (e.g., actual volume flow rate) must also meet all 
accuracy and measurement requirements of section 5.2 of ISO 
1217:2009(E). 81 FR 27220, 27241 (May 5, 2016).
     Any temperature measurement equipment used in a 
calculation of another variable (e.g., actual volume flow rate) must 
also meet all accuracy and measurement requirements of section 5.3 of 
ISO 1217:2009(E). 81 FR 27220, 27241 (May 5, 2016).
     Where ISO 1217:2009(E) refers to ``corrected volume flow 
rate,'' the term is deemed synonymous with the term ``actual volume 
flow rate,'' as defined in section 3.4.1 of ISO 1217:2009(E). 81 FR 
27220, 27238 (May 5, 2016).
     The piping connected to the discharge orifice of the 
compressor must be of a diameter at least equal to that of the 
compressor discharge orifice to which it is connected. The piping must 
be straight with a length of at least 15 times the diameter of the 
discharge piping. 81 FR 27220, 27241 (May 5, 2016).
     The pressure tap must be located on the discharge piping 
between 2 inches and 6 inches, inclusive, from the discharge orifice of 
the compressor at the higher point of the cross-section of the pipe. 81 
FR 27220, 27241 (May 5, 2016).
    DOE received specific comments related to the proposed requirements 
for equipment used to measure input power, air density, and pressure as 
well as requirements regarding their installation location. These 
comments are discussed in detail in the sections that follow.

[[Page 1077]]

    Aside from the input power, pressure, and air density measurement 
equipment, DOE received no specific comments related to the remainder 
of this proposal. CAGI commented that it was in agreement with DOE's 
proposal for items on which it did not directly comment. (CAGI, No. 
0010, p. 3) Ingersoll Rand, Sullair, and Sullivan-Palatek supported 
CAGI's comments. (Ingersoll Rand, No. 0011 at p. 1; Sullair, No. 0006 
at p. 1; Sullivan-Palatek, No. 0007 at p. 1) Consequently, for the 
reasons established in the test procedure NOPR, DOE is adopting the 
measurement equipment requirements (excluding input power, pressure, 
and air density measurement equipment) as proposed in the test 
procedure NOPR in this final rule.
a. Input Power Measurement
    In the test procedure NOPR, DOE proposed that measurement equipment 
used for packaged compressor power input must comply with the equipment 
and accuracy requirements in section C.2.4 of Annex C of ISO 
1217:2009(E). 81 FR 27220, 27257 (May 5, 2016). Section C.2.4 of Annex 
C of ISO 1217:2009(E) permits two methods to determine packaged 
compressor power input; (1) the double element wattmeter method, which 
gives a direct indication of the electrical kilowatt/input; and (2) a 
computation based on the separate measurements of voltage, current and 
power factor of the electrical supply.
    DOE proposed requiring electrical measurement equipment to be 
capable of measuring true RMS current, true RMS voltage, and real power 
up to the 40th harmonic of fundamental supply source frequency. It also 
proposed requiring this equipment to have a combined accuracy of 2.0 percent of the measured value at the fundamental supply 
source frequency, where combined accuracy is the square root of the sum 
of the squares of individual instrument accuracies. 81 FR 27220, 27240 
(May 5, 2016).
    In response to DOE's proposal, Scales Industrial Technologies 
recommended that power measurements should use the two- or three-
wattmeter method, and not individual measurements of voltage, current, 
and power factor. (Scales Industrial Technologies, No. 0013 at p. 5) In 
response to Scales Industrial Technologies comment, DOE concludes that 
power measurements should not be restricted to the double element 
wattmeter method, because ISO 1217:2009(E), as amended,\25\ allows 
power to be calculated from individual measurements, and these 
measurements would need to meet the additional accuracy and measurement 
requirements DOE proposed in the test procedure NOPR. So long as these 
requirements are met, DOE concludes that either method in section C.2.4 
of Annex C of ISO 1217:2009(E), as amended, will produce valid and 
repeatable results. DOE notes that some manufacturers and customers may 
value measurement of power factor, and wishes to preserve their current 
ability to use it.
---------------------------------------------------------------------------

    \25\ In this final rule, DOE is incorporating by reference parts 
of ISO 1217:2009(E) as amended by Amendment 1:2016. Amendment 1:2016 
did not introduce any changes in regards to this particular topic.
---------------------------------------------------------------------------

    CAGI did not directly comment on this item, but CAGI commented that 
it was in agreement with DOE's proposal for items on which it did not 
directly comment. (CAGI, No. 0010, p. 3) Ingersoll Rand, Sullair, and 
Sullivan-Palatek supported CAGI's comments. (Ingersoll Rand, No. 0011 
at p. 1; Sullair, No. 0006 at p. 1; Sullivan-Palatek, No. 0007 at p. 1) 
ASAP and NEEA also supported the proposed electrical measurement 
requirements. (ASAP and NEEA, No. 0015 at p. 3) However, Sullair also 
commented that for large air compressors above 200 hp, many units come 
with high-voltage equipment in the range of 2,300 or 4,160 volts, which 
makes the proposed limits for harmonics, THD, and voltage accuracy 
difficult to guarantee. (Sullair, No. 0006 at p. 4) DOE acknowledges 
Sullair's concern regarding compressors above 200 hp, however, in this 
final rule DOE is restricting to the scope of the test procedure to 
compressors with less than or equal to 200 compressors motor nominal 
horsepower. As such, the concerns raised by Sullair are no longer 
applicable.
    Conversely, Jenny Products commented that power measuring devices 
are already regulated by the Air Conditioning, Heating, and 
Refrigeration Institute (AHRI) and the Canadian Standards Association 
(CSA). As a result, Jenny Products commented that any accuracy beyond 
that required by AHRI and CSA increases the cost of the equipment, 
increases the cost of certifying the equipment, reduces the reliability 
of the equipment, and imposes an additional financial burden to small 
manufacturers. (Jenny Products, No. 0020 at p. 4) DOE acknowledges 
comments made by Jenny Products and wishes to clarify that the CSA and 
AHRI do not certify or regulate the accuracy of power measurement 
equipment. The CSA product design and testing guidelines are intended 
to ensure the safe operation of products. AHRI provides standard test 
procedures for rating the performance of air conditioning, heating, and 
refrigeration equipment. As a result, DOE proposed requirements for the 
power measurement equipment in the absence of a standard accuracy 
requirement that ensures an equitable test for compressors regardless 
of testing location.
    In summary, based on the general support provided by ASAP, NEEA, 
CAGI, Sullivan-Palatek, Ingersoll Rand, and Sullair, and for the 
reasons discussed in this section and the test procedure NOPR, DOE is 
adopting power measurement requirements, as proposed in the test 
procedure NOPR.
b. Pressure Measurement
    In the test procedure NOPR, DOE proposed that equipment used for 
pressure measurement must comply with the requirements in section 5.2 
of ISO 1217:2009(E). DOE also proposed additional requirements to 
remedy what it believed to be certain ambiguities in section 5.2 of ISO 
1217:2009(E). Specifically, DOE proposed that discharge piping be at 
least equal in diameter to the discharge port and of at least 15 times 
that diameter in length. DOE also proposed that the pressure 
transducers be placed on the discharge piping between 2 inches and 6 
inches from the discharge orifice of the compressor. Finally, DOE 
requested clarifications, but did not propose any itself, for a number 
of other ambiguities in section 5.2. 81 FR 27220, 27240-1 (May 5, 
2016).
    DOE received several comments on its proposals for discharge 
piping. CAGI agreed that the discharge pipe should be equal to, or 
greater than, the discharge orifice in diameter, and that the pressure 
tap should be located 2 to 6 inches from the compressor discharge. 
(CAGI, No. 0010 at p. 10; CAGI, Public Meeting Transcript, No. 0016 at 
pp. 89-90) Jenny Products made similar comments to CAGI's regarding the 
discharge pipe diameter, but suggested that the pressure tap be located 
on a receiver. (Jenny Products, No. 0020 at p. 4) However, CAGI did not 
see a need for a discharge pipe with a length of 15 times the diameter 
of the compressor discharge; instead, CAGI recommended a 6-inch minimum 
discharge pipe. (CAGI, No. 0010 at p. 10; CAGI, Public Meeting 
Transcript, No. 0016 at pp. 89-90) CAGI indicated that the use of an 
insertion-type mass flowmeter is the only possible reason to require a 
discharge pipe with the length proposed by DOE. CAGI indicated that ISO 
1217 specifies that nozzles should be used for measuring flow and 
insertion-type

[[Page 1078]]

flowmeters should not be used. (CAGI, No. 0010 at p. 10; CAGI, Public 
Meeting Transcript, No. 0016 at pp. 89-90) Sullair and Kaeser 
Compressors supported CAGI's opinions on the length of the discharge 
pipe. (Sullair, Public Meeting Transcript, No. 0016 at p. 91; Kaeser 
Compressors, Public Meeting Transcript, No. 0016 at pp. 92-93) Atlas 
Copco commented that it is possible for the test procedure to specify 
only the accuracy required, and not require a specific length of 
discharge pipe similar to the approach of ISO 1217:2009(E). (Atlas 
Copco, Public Meeting Transcript, No. 0016 at p. 94) Scales Industrial 
Technologies stated that the length of pipe varies with the type of 
meter, but that 15 times the diameter is acceptable in most cases. 
Scales Industrial Technologies also stated that, in many cases, it is 
also important to specify a required length of piping for the outlet of 
the flow measurement device. (Scales Industrial Technologies, No. 0013 
at p. 6) Compressed Air Systems commented that the distance requirement 
had no merit and would add unnecessary cost to the test equipment 
required. (Compressed Air Systems, No. 0008 at p. 2)
    In response to comments, DOE clarifies that it did not specify a 
discharge pipe length equal to 15 times the diameter of the outlet in 
order to accommodate insertion-type flowmeters. DOE specified this 
length to avoid oscillations in outlet pressure that can occur when an 
elbow or bend is placed a short distance from the compressor outlet. 
Kaeser Compressors acknowledged this need to ensure an adequate 
distance of discharge pipe before an elbow. (Kaeser Compressors, Public 
Meeting Transcript, No. 0016 at p. 93)
    In response to commenters' concerns, DOE is adopting changes to its 
proposals for discharge piping in this final rule. Specifically, DOE is 
adopting the requirement that discharge pipe be a minimum of 6 inches 
long while also adopting tolerance for oscillations in outlet pressure 
as part of its stability criteria, as outlined in section III.E.4. This 
change aligns with recommendations of CAGI, Sullair, Kaeser 
Compressors, and Atlas Copco, and allows test labs to determine the 
length of discharge pipe that is required to ensure that outlet 
pressure oscillations remain within the stability criteria.
    Further, based on the support received from CAGI, and for the 
reasons outlined in the test procedure NOPR, DOE is adopting its 
proposals that discharge piping be at least equal in diameter to the 
discharge port and that the pressure transducers be placed on the 
discharge piping between 2 inches and 6 inches from the discharge port.
    DOE is also clarifying in this final rule that the pressure tap for 
the discharge pressure transducers is to be located at the highest 
point of the discharge pipe's cross section. In the test procedure 
NOPR, DOE stated that the discharge pressure transducers must be 
mounted on the discharge piping. As a result, DOE is revising the 
phrasing in this final rule to make clear the required location of the 
pressure tap for the discharge pressure transducers.
    DOE also received comments on its request for clarifications of the 
ambiguities in section 5.2 of ISO 1217:2009(E). CAGI indicated that 
much of the content that DOE found ambiguous is intended as guidance 
for testers to eliminate leaks and ensure good data. (CAGI, No. 0010 at 
p. 10; CAGI, Public Meeting Transcript, No. 0016 at p. 89-90) Atlas 
Copco requested clarification of the ambiguities in section 5.2.1 of 
ISO 1217:2009(E), especially on the elimination of leaks. (Atlas Copco, 
No. 0009 at p. 17-18) Scales Industrial Technologies noted that some of 
the ambiguities appear to be applicable to larger reciprocating 
compressors and not for rotary screw models. (Scales Industrial 
Technologies, No. 0013 at p. 6) Jenny Products advised that leak 
detection can be conducted with soapy water and a paint brush, stated 
that pipes should be tight enough such that they don't leak, and 
suggested that a flexible hose be used to reduce vibration. (Jenny 
Products, No. 0020 at p. 4)
    Upon review, DOE agrees with CAGI that most of the material in 
section 5.2 of ISO 1217:2009(E) is guidance for testers and is not 
required to perform a repeatable and accurate test. DOE believes that 
the accuracy requirements in section 5.2 are required, but that testers 
can consider the other materials as guidance. DOE also does not believe 
that the guidance materials prevent the performance of a repeatable and 
accurate test. Some of the guidance material might also help testers to 
avoid leaks in the system. As a result, in this final rule, DOE is 
adopting its proposal to incorporate by reference all of section 5.2 in 
ISO 1217:2009(E), as amended.\26\
---------------------------------------------------------------------------

    \26\ In this final rule, DOE is incorporating by reference parts 
of ISO 1217:2009(E) as amended by Amendment 1:2016. Amendment 1:2016 
did not introduce any changes in regards to this particular topic.
---------------------------------------------------------------------------

c. Air Density Measurement
    In the test procedure NOPR, DOE proposed that any measurement of 
air density have an accuracy of  1.0 percent of the 
measured value. 81 FR 27220, 27241 (May 5, 2016). In response to DOE's 
proposal, Kaeser Compressors commented at the public meeting that they 
agreed with the proposed accuracy requirement on the measurement of air 
density and clarified that manufacturers calculate density using other 
measured parameters in accordance with the test procedure. (Kaeser 
Compressors, Public Meeting Transcript, No. 0016 at p. 87-88) CAGI did 
not directly comment on this item, but CAGI commented that it was in 
agreement with DOE's proposals of items on which CAGI did not directly 
comment. (CAGI, No. 0010, p. 3) Ingersoll Rand, Sullair, and Sullivan-
Palatek supported CAGI's comments. (Ingersoll Rand, No. 0011 at p. 1; 
Sullair, No. 0006 at p. 1; Sullivan-Palatek, No. 0007 at p. 1)
    In response to Kaeser Compressors, DOE clarifies that the intent of 
its test procedure NOPR proposal was that any direct measurement of 
density must have an accuracy of  1.0 percent of the 
measured value. Consequently, for the reasons established in the test 
procedure NOPR DOE is adopting the accuracy requirements for air 
density measure, as proposed in the test procedure NOPR, with the minor 
clarification that such requirements only apply to directly measured 
values.
2. Test Conditions
    In the test procedure NOPR, DOE proposed that for both fixed-speed 
and variable-speed compressors, testing be conducted in accordance with 
the test conditions, unit configuration, and specifications of 
subsections 6.2(g), 6.2(h), of ISO 1217:2009(E) and C.1.1, C.2.2, 
C.2.3, C.2.4, C.4.1, C.4.2.1, C.4.2.3, C.4.3.2, and C.4.4 of Annex C to 
ISO 1217:2009(E), Annex C. 81 FR 27220, 27238 (May 5, 2016). In 
response to the test procedure NOPR, CAGI commented that it was in 
agreement with DOE's proposals of items on which CAGI did not directly 
comment. (CAGI, No. 0010, p. 3) Ingersoll Rand, Sullair, and Sullivan-
Palatek supported CAGI's comments. (Ingersoll Rand, No. 0011 at p. 1; 
Sullair, No. 0006 at p. 1; Sullivan-Palatek, No. 0007 at p. 1) 
Consequently, for the reasons established in the test procedure NOPR 
DOE is adopting the requirements as proposed in the test procedure 
NOPR.
    In addition, DOE proposed specific requirements for the power 
supply and ambient conditions. These proposals and related comments are 
discussed in the following sections.

[[Page 1079]]

a. Power Supply
    In the test procedure NOPR, DOE noted that ISO 1217:2009(E) does 
not specify the power supply characteristics required for testing. As 
such, DOE proposed a set of requirements based on those adopted for 
similar equipment (i.e., pumps); specifically these requirements were: 
(a) Input voltage at 5 percent of the rated value of the 
motor; (b) input frequency at 1 percent of the rated value 
of the motor; (c) input voltage unbalance at 3 percent of 
the rated value of the motor; and d) total harmonic distortion at less 
than or equal to 12 percent. 81 FR 27220, 27238-9 (May 5, 2016).
    Jenny Products commented that the power supplied to their facility, 
as well as other companies, do not meet the requirements proposed in 
the test procedure NOPR. (Jenny Products, No. 0020 at p. 3) Similarly, 
Compressed Air Systems argued that the electrical conditions should be 
recorded at the time of the test, but that creating a nearly static 
electrical condition is unnecessary because those conditions would 
rarely be seen in field applications. According to Compressed Air 
Systems, this approach would enable manufacturers to use existing 
equipment for the test. Compressed Air Systems further stated that the 
tolerances proposed in the test procedure NOPR would create undue 
compliance expense. (Compressed Air Systems, No. 0008 at p. 2) In 
response to Compressed Air Systems, DOE clarifies that it did not 
propose nearly static electrical conditions. Rather, DOE proposed 
tolerance ranges that define the acceptable condition of the power 
inputted to a compressor under test. The purpose of power supply and 
other testing tolerances is to ensure that all compressors are tested 
under similar conditions that result in fair and equitable ratings. 
Omitting or relaxing power supply tolerances, as implied by Compressed 
Air Systems and Jenny Products, respectively, and just requiring 
conditions to be recorded would not result in an equitable test, as 
large variations in power supply conditions can have a significant 
impact on the energy efficiency of a compressor under test and affect 
the repeatability of the test procedure.
    Scales Industrial Technologies agreed with DOE's proposed voltage 
and frequency tolerance requirements, and stated that they should be 
less than 5 percent because many motors have efficiency reductions 
beyond 10 percent. Scales Industrial Technologies also stated that a 
voltage unbalance greater than 1 percent is not acceptable and can lead 
to significant increases in motor electric current. (Scales Industrial 
Technologies, No. 0013 at p. 5) Scales Industrial Technologies noted 
that the motor amps may increase by two times the square of the voltage 
unbalance and included a representation that shows the effect of 
voltage variation on ``T'' frame motor performance. (Scales Industrial 
Technologies, No. 0017.1 at p. 1; Scales Industrial Technologies, No. 
0017.2 at p. 1)
    CAGI suggested that the voltage tolerance range should be from 5 
percent below to 10 percent above the nameplate voltage, and claimed 
that the range proposed by DOE would require significant and costly 
adaptations by the labs with negligible impact on test results. CAGI 
also suggested that the frequency tolerance should be 5 
percent and that the voltage imbalance should be 3 percent. 
CAGI further suggested that DOE consider input provided by 
manufacturers regarding the total harmonic distortion tolerance, but 
had internal feedback that the range should be somewhere between 12 and 36 percent. (CAGI, No. 0010 at p. 8-9) 
Ingersoll Rand, Sullair, and Sullivan-Palatek supported CAGI's 
comments. (Ingersoll Rand, No. 0011 at p. 1; Sullair, No. 0006 at p. 1; 
Sullivan-Palatek, No. 0007 at p. 1)
    CAGI's written comment, which were supported by other commenters, 
differs slightly from its original voltage tolerance proposal during 
the June 2016 public meeting. At the public meeting, CAGI suggested a 
10 percent voltage tolerance. (CAGI, Public Meeting 
Transcript, No. 0016 at pp. 96-7) This is slightly wider than its 
written proposal of 5 percent below to 10 percent above the nameplate 
voltage. (CAGI, No. 0010 at p. 8-9) Sullivan-Palatek, Kaeser 
Compressors, and Sullair supported CAGI's proposal at the public 
meeting. (Sullivan-Palatek, Public Meeting Transcript, No. 0016 at p. 
97; Kaeser Compressors, Public Meeting Transcript, No. 0016 at p. 98; 
Sullair, Public Meeting Transcript, No. 0016 at p. 98) Compressed Air 
Systems expressed a preference for testing at the nameplate voltage. 
(Compressed Air Systems, Public Meeting Transcript, No. 0016 at p. 99) 
Sullair reiterated that they believed 10 percent was a tolerance that 
manufacturers could work with. (Sullair, Public Meeting Transcript, No. 
0016 at p. 100) Sullivan-Palatek stated that manufacturers often do not 
have controlled voltage at its facilities, but the test labs generally 
do. (Sullivan-Palatek, Public Meeting Transcript, No. 0016 at pp. 102-
3)
    DOE agrees with Scales Industrial Technologies that a narrow 
voltage, frequency, and voltage unbalance tolerance may improve 
accuracy and repeatability. However, DOE also agrees with CAGI, 
Ingersoll Rand, Kaeser Compressors, Sullair, and Sullivan-Palatek that 
there may be significant test burden associated with narrower voltage, 
frequency, and voltage unbalance tolerance ranges, and that this burden 
may not be justified by a minor increase in accuracy and repeatability. 
Therefore, in response to commenters concern of testing burden, in this 
final rule DOE adopts the broader voltage and frequency range proposed 
by CAGI in its written comment, i.e., - 5 to +10 percent, and 5 percent, respectively. DOE also adopts the voltage unbalance 
tolerance of 3 percent, unchanged, as proposed in the test 
procedure NOPR.
    With regard to total harmonic distortion, CAGI suggested that a 
range of 12 to 36 percent seemed appropriate, 
but commented that individual manufacturers would make recommendations 
as well. (CAGI, No. 0010 at pp. 8-9) DOE did not receive input from any 
of the other commenters with regard to total harmonic distortion. DOE 
adopts the test procedure NOPR proposal for total harmonic distortion 
tolerances without change. These changes pertain only to the power 
supply, fall within the range suggested by CAGI, and do not translate 
into a wider tolerance on the reported results.
b. Ambient Conditions
    In the test procedure NOPR, DOE specifically proposed ambient test 
conditions. In addition to incorporating sections 6.2 g and 6.2 h of 
ISO 1217:2009(E), DOE proposed that testing should occur with an 
ambient air temperature of 80-90 [deg]F, because this is the range that 
the CAGI Performance Verification Program uses. DOE proposed no 
requirements for inlet pressure or relative humidity. 81 FR 27220, 
27238 (May 5, 2016).
    DOE received several comments on these proposals. CAGI agreed with 
the proposed ambient conditions in principle, but stated that the 
proposed range would be overly burdensome for manufacturers and that 
ambient temperature does not affect test results. (CAGI, No. 0010 at p. 
8; CAGI, Public Meeting Transcript, No. 0016 at pp. 76-77) CAGI 
proposed, instead, an ambient air temperature range of 68-
90[emsp14][deg]F. (CAGI, No. 0010, p. 8; CAGI, Public Meeting 
Transcript, No. 0016 at pp. 76-77) Several manufacturers supported and 
echoed CAGI's statements. (Sullivan-Palatek, No. 0007 at p. 3; 
Sullivan-Palatek, Public Meeting Transcript, No. 0016 at pp. 77-78;

[[Page 1080]]

Kaeser Compressors, Public Meeting Transcript, No. 0016 at p. 79; 
Compressed Air Systems, No. 0008 at p. 2; Jenny Products, No. 0020 at 
p. 3) Scales Industrial Technologies stated that the temperature range 
should be resolved between the manufacturers and the testing companies, 
and that the proposed 80-90[emsp14][deg]F temperature range may be hard 
to maintain for some compressors. (Scales Industrial Technologies, No. 
0013 at p. 4) Sullivan-Palatek further stated that the measured 
efficiency of an air compressor is not affected when narrowing the 
temperature range from 68-90[emsp14][deg]F to 80-90[emsp14][deg]F 
according to testimony from industry engineers. (Sullivan-Palatek, No. 
0007 at p. 3)
    In response to ambient temperature concerns at the June 17, 2016, 
public meeting DOE stated that it was willing to consider CAGI's 
proposed temperature range. DOE also requested data to substantiate 
manufacturer claims that ambient temperature does not affect measured 
efficiency. (DOE, Public Meeting Transcript, No. 0016 at pp. 78-9). 
Kaeser Compressors responded by stating that Sullivan-Palatek 
compressors are tested at ambient temperatures below 80[emsp14][deg]F, 
and their performance is verified at 80-90[emsp14][deg]F, indicating 
that temperature does not affect compressor efficiency. (Kaeser 
Compressors, Public Meeting Transcript, No. 0016 at p. 79) Test data 
was not made available to DOE to support or refute the claims made by 
CAGI. Conversely, in written comments, Jenny Products stated that 
ambient temperature needs to be corrected for because it will affect 
test results. Further, Jenny suggested that the ``reference ranges and 
their subsequent correction factors'' be examined to avoid adding undue 
financial burden to small manufacturers, which DOE interpreted as 
comments being directed to the ambient conditions and applicable 
correction factors that have been defined as part of this test 
procedure. (Jenny Products, No. 0020 at p. 3) However, Jenny provided 
no quantitative or qualitative data or information to support the claim 
that the ambient temperature in the test location that a compressor is 
tested in impacts test results. Further, DOE notes that ISO 1217:2009, 
which is the industry accepted test method, does not specify a required 
ambient temperature range for testing.
    Additionally, Sullivan-Palatek stated that many small businesses 
may not control the ambient temperature at which they test their 
compressors. (Sullivan-Palatek, No. 0007 at p. 3) Jenny Products 
commented that they do not have a climate-controlled room to test 
compressors, which would be problematic for winter testing as they are 
located in a cold climate. (Jenny Products, No. 0020 at p. 3) 
Compressed Air Systems also made comments that suggested that it does 
not control the ambient temperature of testing facilities. (Compressed 
Air Systems, No. 0008 at p. 2)
    DOE acknowledges comments made by Compressed Air Systems and Jenny 
Products and agrees that the need to create a climate-controlled space 
for testing compressors could be a significant burden on these small 
businesses. Therefore, in this final rule, DOE is relaxing the proposal 
in the test procedure NOPR to limit ambient temperature to 68-
90[emsp14][deg]F, as suggested by CAGI. DOE concludes this temperature 
range provides representative measurements without imposing undue test 
burden on manufacturers.
    DOE received no comments directly regarding the remaining test 
condition requirements proposed in the test procedure NOPR. 
Consequently, for the reasons established in the test procedure NOPR, 
DOE is adopting its proposal not to establish requirements for inlet 
pressure and relative humidity.
3. Equipment Configuration
    In the test procedure NOPR, DOE proposed the following requirements 
related to equipment configuration for test:
     All ancillary equipment that is distributed in commerce 
with the compressor under test must be present and installed for all 
tests specified in this appendix. 81 FR 27220, 27239 (May 5, 2016).
     The inlet of the compressor under test must be open to the 
atmosphere and take in ambient air for all tests specified in this 
appendix. 81 FR 27220, 27239 (May 5, 2016).
     The compressor under test must be set up according to all 
manufacturer instructions for normal operation (e.g., verify oil-level, 
connect all loose electrical connections, close-off bottom of unit to 
floor, cover forklift holes). 81 FR 27220, 27239 (May 5, 2016).
    As discussed in section III.A.3.b, CAGI provided a list of 
equipment that it believed should be included for testing. CAGI also 
suggested that if a unit is offered for sale without a piece of 
equipment on its recommended list, the manufacturer must provide an 
appropriate component, and the selection and responsibility of 
providing and installing this component for testing shall be the 
responsibility of the manufacturer. (CAGI, No. 0010 at pp. 3-5)
    As discussed in section III.A.3.b, DOE is adopting in this final 
rule a required minimum equipment configuration for compressor testing. 
This configuration is based on the list provided by CAGI, with some 
modifications. CAGI's list included many caveats and footnotes related 
to applicability of certain equipment to certain compressors, which DOE 
found to be ambiguous. In the interest of clarity, DOE is splitting 
CAGI's list into two separate lists, as shown in Table III.2 and Table 
III.3, and adopting these lists to describe the minimum equipment 
configuration for compressor testing. The first list contains equipment 
that must be included on a unit when testing, regardless of whether it 
is distributed in commerce with the basic model under test. This table 
aligns with many of the items that CAGI specified as ``yes.'' The 
second list contains equipment that is only required if it is 
distributed in commerce with the basic model under test. This 
represents much of the equipment that CAGI specified as ``if 
applicable.'' DOE believes that it is impossible to require the 
equipment on Table III.3 for testing, as many basic models do not 
require some of this equipment to achieve their basic functionality and 
adding such equipment is impossible or impractical.
    Further, DOE agrees with CAGI and is adopting the provision that if 
a unit is offered for sale without a piece of equipment listed in Table 
III.2, the manufacturer must provide an appropriate component, and the 
selection and responsibility of providing and installing this component 
for testing shall be the responsibility of the manufacturer. The only 
alternative option under this testing structure would be for the 
testing laboratory to determine the needed specifications of the 
missing component and furnish that item. Based on discussion with 
industry testing experts, DOE concludes that this is not a reasonable 
alternative. A testing laboratory does not have the expertise to 
determine the needed specifications of the component, so the laboratory 
cannot reliably choose the component. In addition, due to the large 
number of ancillary components and the wide range of compressor sizes, 
it is impractical for DOE to specify the characteristics of these 
components as part of the test procedure. DOE is also adopting the 
requirement that DOE install any additional ancillary equipment 
provided by the manufacturer prior to performing enforcement testing of 
a compressor.
    Additionally, DOE is specifying that additional ancillary equipment 
may be installed for testing, if distributed in

[[Page 1081]]

commerce with a compressor, but this additional ancillary equipment is 
not required. This approach is consistent with the approach taken in 
the EU Lot 31 draft standard. DOE notes that it will not install any 
non-required ancillary equipment during any DOE-run assessment or 
enforcement testing. The list that CAGI provided is slightly modified 
from the list used by the EU Lot 31 draft standard, and the EU Lot 31 
draft standard specifies the list as a minimum configuration.

                               Table III.2--List of Equipment Required During Test
----------------------------------------------------------------------------------------------------------------
                                                                                  Variable-speed  rotary air
               Equipment                Fixed-speed rotary  air compressors              compressors
----------------------------------------------------------------------------------------------------------------
Driver................................  Yes................................  Yes.
Bare compressors......................  Yes................................  Yes.
Inlet filter..........................  Yes................................  Yes.
Inlet valve...........................  Yes................................  Yes.
Minimum pressure check valve/backflow   Yes................................  Yes.
 check valve.
Lubricant separator...................  Yes................................  Yes.
Air piping............................  Yes................................  Yes.
Lubricant piping......................  Yes................................  Yes.
Lubricant filter......................  Yes................................  Yes.
Lubricant cooler......................  Yes................................  Yes.
Thermostatic valve....................  Yes................................  Yes.
Electrical switchgear or frequency      Yes................................  Not applicable *.
 converter for the driver.
Device to control the speed of the      Not applicable **..................  Yes.
 driver (e.g., variable speed drive).
Compressed air cooler(s)..............  Yes................................  Yes.
Pressure switch, pressure transducer,   Yes................................  Yes.
 or similar pressure control device.
Moisture separator and drain..........  Yes................................  Yes.
----------------------------------------------------------------------------------------------------------------
* This category is not applicable to variable-speed rotary air compressors.
** This category is not applicable to fixed-speed rotary air compressors.


      Table III.3--List of Equipment Required During Test, if Distributed in Commerce With the Basic Model
----------------------------------------------------------------------------------------------------------------
                                                                                  Variable-speed  rotary air
               Equipment                Fixed-speed rotary  air compressors              compressors
----------------------------------------------------------------------------------------------------------------
Cooling fan(s) and motors.............  Yes................................  Yes.
Mechanical equipment..................  Yes................................  Yes.
Lubricant pump........................  Yes................................  Yes.
Interstage cooler.....................  Yes................................  Yes.
Electronic or electrical controls and   Yes................................  Yes.
 user interface.
All protective and safety devices.....  Yes................................  Yes.
----------------------------------------------------------------------------------------------------------------

    DOE is also adopting some changes to the individual items included 
in the list from CAGI. DOE has changed any mention of ``oil'' in the 
list to ``lubricant,'' in order to be consistent with the terminology 
throughout the test procedure. DOE has added interstage cooler to the 
list of items that must be included if they are distributed in commerce 
with the compressor, to ensure that interstage coolers are not removed 
from a compressor for testing.
    DOE is revising and clarifying the ``compressor control device'' 
item from CAGI's list. DOE is including ``pressure switch, pressure 
transducer, or similar pressure control device'' in the list of 
equipment that is required during a test, because all compressors must 
have the ability to load and unload in response to changes in outlet 
pressure. DOE is also including ``electronic or electrical controls and 
user interface'' in the list of equipment required during a test, if 
distributed in commerce with the basic model. Many compressors include 
controls that perform other tasks beyond controlling pressure, such as 
cycling the intercoolers or fans on and off depending upon temperature. 
In addition, many compressors include an interface panel through which 
a user can get information and control the compressor. This equipment, 
if present, impacts the energy consumption of the packaged compressor, 
and should be accounted for. As such, electronic or electrical controls 
and user interfaces must be included if they are distributed in 
commerce with the compressor.
    DOE is adopting modifications to the electrical switchgear and 
frequency converters included in CAGI's list. DOE is specifying that 
that electrical switchgear or a frequency converter must be included 
for fixed-speed compressors, to ensure that there is a method to turn 
the driver on and off. For variable-speed compressors, DOE is adopting 
the requirement that they include a device to control the speed of the 
driver. CAGI had specified that a frequency converter be required for 
variable-speed compressors (CAGI, No. 0010 at pp. 4) A frequency 
converter is a common device for controlling the speed of an electric 
motor, but there may be other devices that can also control the driver 
speed. Therefore, DOE is only specifying that a piece of equipment 
capable of controlling driver speed is required. DOE is doing this to 
ensure that the requirement is only for the performance of the device, 
and is not a prescriptive requirement for a particular technology to 
control motor speed.
    DOE is also aware that certain rotary compressors are distributed 
in commerce with storage tanks. CAGI commented that for reciprocating 
compressors, storage tanks should be included in the test when they are 
part of the package offered by manufacturers, because their inclusion 
will not affect performance. (CAGI, No. 0010 at p. 5) DOE reviewed this 
issue with an industry testing expert and concluded

[[Page 1082]]

that CAGI's comment is also relevant to rotary compressors distributed 
in commerce with tanks; i.e., tanks on rotary compressors will not 
affect rotary compressor performance either. Consequently, DOE 
concludes that tanks may be included during testing, if distributed in 
commerce with a compressor, but tanks are not required during testing.
    Defining the list of equipment that must be installed as part of 
the test procedure addresses comments made by Jenny Products that 
identified a loophole, which would allow a manufacturer to remove 
ancillary equipment from the basic compressor package to improve the 
efficiency of the unit and sell the ancillary equipment as an optional 
package separate from the compressor. (Jenny Products, No. 0020 at p. 
3)
    DOE received no comments directly regarding the remaining equipment 
configuration requirements proposed in the test procedure NOPR. 
Consequently, for the reasons established in the test procedure NOPR, 
DOE is adopting its proposal that the compressor inlet be open to 
ambient conditions and intake ambient air during testing and the 
compressor under test must be set up according to all manufacturer 
instructions for normal operation.
4. Data Collection and Analysis
a. Stabilization and Data Sampling and Frequency
    In the test procedure NOPR, DOE proposed several requirements for 
data collection and sampling. DOE proposed to require that measurements 
be taken at steady-state conditions, which are achieved when the 
difference between two consecutive, unique, power measurements, taken 
at least 10 seconds apart and no more than 60 seconds apart and 
measured per section C.2.4 of Annex C to ISO 1217:2009(E), is less than 
or equal to 300 watts. 81 FR 27220, 27239 (May 5, 2016).
    DOE also proposed that at each load point, a minimum of 16 unique 
measurements must be recorded over a minimum time of 15 minutes. Each 
consecutive measurement must be no more than 60 seconds apart, no less 
than 10 seconds apart, and the difference in packaged compressor power 
input between the maximum and minimum measurement must be equal to or 
less than 300 watts, as measured per section C.2.4 of Annex C to ISO 
1217:2009(E). Each measurement within the data recording must meet 
these requirements. If one or more measurements do not meet the 
requirements, the tester must take a new data recording of at least 16 
new unique measurements collected over a minimum period of 15 minutes. 
81 FR 27220, 27239 (May 5, 2016).
    DOE received a number of comments in response to data collection 
and sampling requirements proposed in the test procedure NOPR. Jenny 
Products commented that the frequency of data sampling seems too high, 
noting that their process of manually recording readings takes more 
than 10 seconds to complete. (Jenny Products, No. 0020 at p. 4) DOE 
wishes to clarify that data samples must be taken between 10 and 60 
seconds apart; DOE believes that 60 seconds provides enough time to 
manually record measurements. CAGI commented that it agrees with the 
proposed data sampling frequency requirements. (CAGI, No. 0010 at p. 
10) Ingersoll Rand, Sullair, and Sullivan-Palatek supported CAGI's 
comments. (Ingersoll Rand, No. 0011 at p. 1; Sullair, No. 0006 at p. 1; 
Sullivan-Palatek, No. 0007 at p. 1) Based on the general support of 
commenters and the reasons established in the test procedure NOPR, DOE 
is adopting the requirements that at each load point, a minimum of 16 
unique measurements must be recorded over a minimum time of 15 minutes 
and each consecutive measurement must be no more than 60 seconds apart, 
and not less than 10 seconds apart.
    However, CAGI commented that it does not agree with the 
requirements of stability. CAGI recommended that DOE adopt Table 1 from 
Section 6.2 of ISO 1217:2009(E), to quantify the maximum permissible 
fluctuation from average during steady-state operation for discharge 
pressure, temperature at the nozzle or orifice plate, and differential 
pressure over the nozzle or orifice plate. CAGI also recommended that 
DOE incorporate by reference sections 6.2(i), 6.2(j), and 6.2(k) to 
help clarify stability. (CAGI, No. 0010 at pp. 6-8, 10; CAGI, Public 
Meeting Transcript, No. 0016 at pp. 74, 83) Ingersoll Rand, Sullair, 
and Sullivan-Palatek supported CAGI's comments. (Ingersoll Rand, No. 
0011 at p. 1; Sullair, No. 0006 at p. 1; Sullivan-Palatek, No. 0007 at 
p. 1) Atlas Copco supports comments made by CAGI with regard to 
adopting the cited sections of ISO 1217:2009(E). (Atlas Copco, No. 0009 
at pp. 17-18) CAGI and Kaeser Compressors commented that the power 
restriction of 300 W, likely taken from the CAGI Performance 
Verification Program, is inappropriate and not followed by some members 
as it is not a realistic stability requirement for larger horsepower 
compressors and that a more appropriate threshold is a percentage of 
full-load power. (CAGI, No. 0010 at p. 10; Kaeser Compressors, Public 
Meeting Transcript, No. 0016 at p. 82-83) CAGI and Kaeser Compressors 
further argue that the power is the measured result of the test, but 
the stability criteria should be strictly based on measured 
temperatures and pressures. (CAGI, No. 0010 at p. 10; Kaeser 
Compressors, Public Meeting Transcript, No. 0016 at p. 84)
    In response to commenters' concerns over the 300 watt stability 
requirement, DOE agrees with the CAGI recommendation that stability 
should be determined using the maximum permissible fluctuation from 
average for discharge pressure, temperature at the nozzle or orifice 
plate, and differential pressure over nozzle or orifice plate from 
Table 1 in ISO 1217:2009(E). Therefore, in this final rule, DOE adopts 
revised requirements stating that steady-state is achieved when the 
difference between two consecutive, unique, measurements taken at least 
10 seconds apart and no more than 60 seconds apart meet all of the 
following requirements from Table 1 of ISO 1217:2009(E), as amended: 
(1) Discharge pressure varies less than or equal to 1 percent from the 
average reading; (2) temperature at the nozzle or orifice plate, 
measured per section 5.3 of ISO 1217:2009(E), as amended, varies less 
than or equal to 2 K from the average reading; and (3) differential 
pressure over nozzle or orifice plate, measured per section 5.2 of ISO 
1217:2009(E), as amended, varies less than or equal to 2 percent from 
the average reading.\27\
---------------------------------------------------------------------------

    \27\ In this final rule, DOE is incorporating by reference parts 
of ISO 1217:2009(E) as amended by Amendment 1:2016. Amendment 1:2016 
did not introduce any changes in regards to this particular topic.
---------------------------------------------------------------------------

    In response to CAGI's additional recommendation that DOE 
incorporate by reference sections 6.2(i), 6.2(j), and 6.2(k) of ISO 
1217:2009(E), DOE reviewed these sections and concluded that these 
sections contain general qualitative guidance for testing, and that the 
same issues are already addressed in various other sections of the test 
procedure being established in this final rule. Therefore, DOE is not 
incorporating these sections in the test procedure.
    Specifically, section 6.2(i) of ISO 1217:2009(E), as amended,\28\ 
states that before readings are taken, the compressor shall be run long 
enough to ensure that steady-state conditions are reached so that no 
systematic changes

[[Page 1083]]

occur in the instrument readings during the test. In response, DOE 
clarifies that in this document DOE is adopting the specific 
requirement that steady-state is achieved when the difference between 
two consecutive, unique, measurements taken at least 10 seconds apart 
and no more than 60 seconds apart meet certain requirements from Table 
1 of ISO 1217:2009(E), as amended. As such, DOE concludes that it is 
unnecessary to incorporate by reference the qualitative guidance 
provided section 6.2(i) of ISO 1217:2009(E), as amended.
---------------------------------------------------------------------------

    \28\ In this final rule, DOE is incorporating by reference parts 
of ISO 1217:2009(E) as amended by Amendment 1:2016. Amendment 1:2016 
did not introduce any changes in regards to this particular topic.
---------------------------------------------------------------------------

    Section 6.2(j) of ISO 1217:2009(E), as amended,\29\ states that, 
should the test conditions be such that systematic changes cannot be 
avoided, or if individual readings are subject to great variations, 
then the number of readings shall be increased. In response, DOE 
clarifies that in this document DOE is adopting the requirement that if 
measurements do not meet stability requirements then a new data 
recording of at least 16 new unique measurements must be taken. As 
such, DOE does not incorporate by reference the qualitative guidance 
provided section 6.2(j) of ISO 1217:2009(E), as amended.
---------------------------------------------------------------------------

    \29\ Ibid.
---------------------------------------------------------------------------

    Section 6.2(k) of ISO 1217:2009(E), as amended,\30\ states that for 
each load, a sufficient number of readings shall be taken to indicate 
that steady-state conditions have been reached. The number of readings 
and the intervals shall be chosen to obtain the required accuracy. In 
response, DOE clarifies that in this document DOE is adopting specific 
requirements that at each load point, a minimum of 16 unique 
measurements must be recorded over a minimum time of 15 minutes and 
each consecutive measurement must be no more than 60 seconds apart, and 
not less than 10 seconds apart. As such, DOE does not incorporate by 
reference the qualitative guidance provided in section 6.2(k) of ISO 
1217:2009(E), as amended.
---------------------------------------------------------------------------

    \30\ In this final rule, DOE is incorporating by reference parts 
of ISO 1217:2009(E) as amended by Amendment 1:2016. Amendment 1:2016 
did not introduce any changes in regards to this particular topic.
---------------------------------------------------------------------------

b. Calculations and Rounding
    In the test procedure NOPR, DOE recognized that the order and 
manner in which values are rounded can affect the final represented 
values produced by the test procedure. DOE noted that ISO 1217:2009(E) 
does not specify rounding requirements. Consequently, DOE proposed its 
own rounding requirements for the calculations and representations 
required by the DOE test procedure. DOE proposed that package 
isentropic efficiency be rounded and represented to the nearest 0.001, 
specific power to the nearest 0.01 kW/100 cfm, pressure ratio to the 
nearest 0.1, actual volume flow rate to the nearest 0.1 cubic feet per 
minute (``cfm''), and full-load operating pressure to the nearest 1 
psig. DOE further proposed to require that all calculations be 
performed with the raw measured data in order to ensure accuracy. 81 FR 
27220, 27240 (May 5, 2016).
    CAGI and Atlas Copco suggested that the full-load operating 
pressure should be expressed to the nearest 0.1 psig to ensure that the 
pressure ratio is not distorted. (CAGI, No. 0010 at p. 10; Atlas Copco, 
No. 0009 at p. 18) Ingersoll Rand, Sullair, and Sullivan-Palatek 
supported CAGI's comments. (Ingersoll Rand, No. 0011 at p. 1; Sullair, 
No. 0006 at p. 1; Sullivan-Palatek, No. 0007 at p. 1)
    In response to CAGI and Atlas Copco's concerns that pressure ratio 
not be distorted, DOE first notes that, as discussed in sections 
III.A.8 and III.E.8, the term referred to as pressure ratio in the test 
procedure NOPR is now referred to as pressure ratio at full-load 
operating pressure in this final rule. Further, in this final rule, DOE 
specifies that all calculations for pressure ratio at full-load 
operating pressure be carried out with the raw measured data. As such, 
the rounding requirement for representations of full-load operating 
pressure does not affect the calculation of the pressure ratio at full-
load operating pressure. Additionally, DOE is not specifying a method 
for calculating pressure ratio at any load point other than full-load 
operating pressure. Therefore, manufacturers are not restricted by any 
specific rounding or representations requirement for such information.
    Based on this consideration, DOE does not believe that stricter 
rounding requirements are necessary in representations of the full-load 
operating pressure. Therefore, in this final rule DOE adopts the test 
procedure NOPR proposal for rounding and calculations requirements.
5. Determination of Full-Load and Part-Load Package Isentropic 
Efficiency
    In the test procedure NOPR, DOE proposed to rate fixed-speed 
compressors with the full-load package isentropic efficiency metric. 
For variable-speed compressors, DOE proposed the use of the part-load 
package isentropic efficiency. 81 FR 27220, 27232-3 (May 5, 2016).
    According to Equation 3 in the proposal, the full-load package 
isentropic efficiency is calculated at the full-load operating 
pressure. 81 FR 27220, 27234 (May 5, 2016).
[GRAPHIC] [TIFF OMITTED] TR04JA17.002

Where:

[eta]isen,FL = [eta]isen,100 = package 
isentropic efficiency at full-load operating pressure and 100 
percent of full-load actual volume flow rate,

Preal,100 = packaged compressor power input at 
full-load operating pressure and 100 percent of full-load actual 
volume flow rate, as determined from Equation 4,\31\ and
---------------------------------------------------------------------------

    \31\ The correction factor for the shaft speed (K4) 
in section C.4.3.1 of Annex C in ISO 1217:2009(E) is not applicable 
to this test procedure because the electric motor drive is included 
in the package, and it is therefore omitted from this equation.
---------------------------------------------------------------------------

Pisen,100 = isentropic power required for 
compression at full-load operating pressure and 100 percent of full-
load actual volume flow rate, as determined from Equation 5.

    As referenced in Equation 3, the packaged compressor power input at 
full-load operating pressure and 100 percent of full-load actual volume 
flow rate was proposed to be determined in accordance with Equation 4. 
81 FR 27220, 27234 (May 5, 2016).
[GRAPHIC] [TIFF OMITTED] TR04JA17.003


[[Page 1084]]


Where:

K5 = correction factor for inlet pressure, as determined 
in section C.4.3.2 of Annex C to ISO 1217:2009(E) at a contractual 
inlet pressure of 100 kPa,\32\ and
---------------------------------------------------------------------------

    \32\ The correction factor for inlet pressure uses contractual 
values for inlet pressure. Since a contractual value is not 
applicable to this test procedure, DOE proposed to use a value of 
100 kPa from Annex F in ISO 1217:2009(E).

PPR,100 = packaged compressor power input reading 
at full-load operating pressure and 100 percent of full-load actual 
volume flow rate (W), as determined in section C.2.4 of Annex C to 
---------------------------------------------------------------------------
ISO 1217:2009(E).

    The isentropic power required for compression at full-load 
operating pressure and 100 percent of full-load actual volume flow rate 
(Pisen,100), shown in equation 5, was proposed to be 
evaluated using measurements taken while the unit is operating at full-
load operating pressure. 81 FR 27220, 27234-5 (May 5, 2016).
[GRAPHIC] [TIFF OMITTED] TR04JA17.004

Where:

V1\m3/s = corrected volume flow rate at full-load operating pressure 
and 100 percent of full-load actual volume flow rate, as determined 
in section C.4.2.1 of Annex C of ISO 1217:2009(E) (cubic meters per 
second) with no corrections made for shaft speed,

p1 = atmospheric pressure, as determined in section 5.2.2 
of ISO 1217:2009(E) (Pa),

p2 = discharge pressure at full-load operating pressure 
and 100 percent of full-load actual volume flow rate, determined in 
accordance with section 5.2 of ISO 1217:2009(E) (Pa), and

[kappa] = isentropic exponent (ratio of specific heats) of air, 
which, for the purposes of this test procedure, is 1.400.\33\
---------------------------------------------------------------------------

    \33\ The isentropic exponent of air has some limited variability 
with atmospheric conditions. DOE chose a fixed value of 1.400 to 
align with the EU Lot 31 draft standard's metric calculations.

    Also according to the test procedure NOPR proposal, the part-load 
efficiency is calculated using Equation 6. 81 FR 27220, 27235-27236 
---------------------------------------------------------------------------
(May 5, 2016).

[GRAPHIC] [TIFF OMITTED] TR04JA17.005

Where:

[eta]isen,PL = part-load package isentropic efficiency 
for a variable-speed compressor,

[eta]isen,100 = package isentropic efficiency at 
full-load operating pressure, as determined in Equation 3,

[eta]isen,70 = package isentropic efficiency at 
70 percent of full-load actual volume flow rate,

[eta]isen,40 = package isentropic efficiency at 
40 percent of full-load actual volume flow rate,

[omega]40 = weighting at 40 percent of full-load 
actual volume flow rate (0.25),

[omega]70 = weighting at 70 percent of full-load 
actual volume flow rate (0.5), and

[omega]100 = weighting at 100 percent of full-
load actual volume flow rate (0.25).

    Package isentropic efficiencies at 70 percent and 40 percent of 
full-load actual volume flow rate were proposed to be calculated using 
equations of the same form as equations 3, 4 and 5, but with the 
necessary modification of the inputs. Thus, for the 70 percent case, 
the packaged compressor power input and the package isentropic 
efficiency are evaluated at 70 percent of the full-load actual volume 
flow rate, and those values are used to calculate the package 
isentropic efficiency at 70 percent. Analogously, for the 40 percent 
case the package compressor power input and the package isentropic 
efficiency are evaluated at 40 percent of the full-load actual volume 
flow rate, and those values are used to calculate the package 
isentropic efficiency at 40 percent.
    In response to the test procedure NOPR, DOE did not receive any 
direct comments on this item. CAGI commented that it was in agreement 
with DOE's proposals of items on which CAGI did not directly comment. 
(CAGI, No. 0010, p. 3) Ingersoll Rand, Sullair, and Sullivan-Palatek 
supported CAGI's comments. (Ingersoll Rand, No. 0011 at p. 1; Sullair, 
No. 0006 at p. 1; Sullivan-Palatek, No. 0007 at p. 1) Consequently, for 
the reasons established in the test procedure NOPR DOE is adopting the 
calculation methods for full-load and part-load package isentropic 
efficiency, as proposed in the test procedure NOPR.
    However, as previously discussed in section III.D, ISO recently 
published an amendment to ISO 1217:2009(E), ISO 1217:2009(E)/Amd.1,\34\ 
which includes formulas for isentropic efficiency and isentropic power. 
DOE reviewed the amendment and notes that the equations provided are 
equivalent to the equations DOE provided in the test procedure NOPR. 
Therefore, in this final rule DOE is amending its proposed test method 
to incorporate ISO 1217:2009(E), as amended, and referencing it for the 
calculation of package isentropic efficiency, rather than directly 
providing all the equations. DOE considers this to be an administrative 
change, as it has no impact on the ultimate result of the test 
procedure.
---------------------------------------------------------------------------

    \34\ ISO 1217:2009(E) and ISO 1217:2009(E)/Amd.1 create one 
amended document, which is referred to in this final rule as ``ISO 
1217:2009(E), as amended.''
---------------------------------------------------------------------------

    In this test procedure final rule, DOE is also establishing certain 
clarifying language that it concludes is required to clearly and 
unambiguously interpret the methods proposed in the test procedure 
NOPR. In the test procedure NOPR, DOE did not specify an operating 
pressure for the points at 70 and 40 percent of full-load actual volume 
flow rate. DOE is specifying in this final rule that these points be 
tested at full-load operating pressure. This is the same pressure used 
for the point at 100 percent of full-load actual volume flow rate.
    DOE is also revising the pressure values used in the calculation of 
isentropic power. In the test procedure NOPR, DOE proposed to correct 
the measured real power to a standard atmospheric pressure of 100 kPa. 
For isentropic power, DOE proposed to use the atmospheric and discharge 
pressure values measured at each load point, without correction for 
atmospheric pressure. This creates an inconsistency, because real power 
is corrected to atmospheric pressure and isentropic power is not. 
Therefore, DOE is adopting a method that calculates the isentropic 
power at a standard atmospheric pressure of 100 kPa. The method 
specifies a discharge pressure that is equal to the sum of 100 kPa and

[[Page 1085]]

the discharge gauge pressure measured during the test.
6. Allowable Deviation From Specified Load Points
    In the test procedure NOPR, DOE proposed to explicitly limit the 
maximum allowable deviation from specified load points when testing to 
find part-load and full-load package isentropic efficiency and pressure 
ratio. Specifically, DOE proposed that maximum allowable deviations 
from the specified discharge pressure and volume flow rate in Tables 
C.1 and C.2 of Annex C of ISO 1217:2009(E) apply. 81 FR 27220, 27239-
27240 (May 5, 2016). DOE also clarified that the term ``volume flow 
rate'' in Table C.2 of Annex C of ISO 1217:2009(E) refers to the actual 
volume flow rate of the compressor under test. 81 FR 27220, 27259 (May 
5, 2016).
    DOE received no comments directly regarding this proposed 
requirement, but notes that CAGI stated that it was in agreement with 
DOE's proposals of items on which CAGI did not directly comment. (CAGI, 
No. 0010, p. 3) Ingersoll Rand, Sullair, and Sullivan-Palatek supported 
CAGI's comments. (Ingersoll Rand, No. 0011 at p. 1; Sullair, No. 0006 
at p. 1; Sullivan-Palatek, No. 0007 at p. 1) Consequently, for the 
reasons established in the test procedure NOPR, DOE is adopting this 
proposal.
7. Determination of Package Specific Power
    In the test procedure NOPR, DOE proposed that package specific 
power can be determined for both fixed and variable-speed air 
compressors at any load point using the equation for specific energy 
consumption in section C.4.4 of Annex C of ISO 1217:2009(E). 81 FR 
27220, 27259 (May 5, 2016). DOE received no comments directly regarding 
this proposed requirement, but notes that CAGI stated that it was in 
agreement with DOE's proposals of items on which CAGI did not directly 
comment. (CAGI, No. 0010, p. 3) Ingersoll Rand, Sullair, and Sullivan-
Palatek supported CAGI's comments. (Ingersoll Rand, No. 0011 at p. 1; 
Sullair, No. 0006 at p. 1; Sullivan-Palatek, No. 0007 at p. 1)
    In this final rule, DOE is adopting a clarification of the method 
for calculating corrected package power input for specific power. The 
clarification ensures that this value is calculated in the same way as 
it is calculated for isentropic efficiency. In the test procedure NOPR, 
DOE did not incorporate by reference the subsection in Annex C of ISO 
1217:2009(E) in which the corrected package power input 
(PPcorr) is calculated. DOE has resolved this ambiguity by 
adopting an equation in this final rule for calculating 
PPcorr.
    DOE is also adopting the clarification that correction for shaft 
speed shall not be performed when calculating package specific power. 
In the NOPR and this final rule, DOE does not allow for shaft speed 
correction when calculating package isentropic efficiency. Therefore, 
DOE believes it is most consistent and clear to require the same 
standards for determining package specific power.
8. Determination of Pressure Ratio at Full-Load Operating Pressure
    In the test procedure NOPR, DOE proposed a method to determine 
pressure ratio. Specifically DOE proposed that pressure ratio be 
defined by the following equation:
[GRAPHIC] [TIFF OMITTED] TR04JA17.006

Where:

PR = pressure ratio

P1 = atmosphere pressure as determined in section 5.2.2 
of ISO 1217:2009(E) (Pa), and

P2 = discharge pressure at full-load operating pressure, 
determined in accordance with section 5.2 of ISO 1217: 2009 (Pa). 81 
FR 27220, 27260 (May 5, 2016).

    CAGI did not directly comment on pressure ratio, but CAGI stated 
that it was in agreement with DOE's proposals of items on which CAGI 
did not directly comment. (CAGI, No. 0010, p. 3) Ingersoll Rand, 
Sullair, and Sullivan-Palatek supported CAGI's comments. (Ingersoll 
Rand, No. 0011 at p. 1; Sullair, No. 0006 at p. 1; Sullivan-Palatek, 
No. 0007 at p. 1)
    As discussed in section III.A.1, Scales Industrial Technologies 
indicated that DOE's proposed definition of pressure ratio was not 
sufficiently clear, and could be interpreted in multiple ways. (Scales 
Industrial Technologies, No. 0013, at p. 1) Jenny Products commented 
that ambient temperature, barometric pressure, humidity, and altitude 
must be corrected for because they will all affect test results. (Jenny 
Products, No. 0020 at p. 3)
    As discussed in section III.A.1, in an effort to add clarity, the 
term referred to as pressure ratio in the test procedure NOPR is now 
referred to as pressure ratio at full-load operating pressure in this 
final rule. Additionally, in this final rule, DOE is incorporating 
clarifying changes to the test method and calculations for pressure 
ratio at full-load isentropic efficiency. Specifically, DOE reviewed 
the test method proposed in the test procedure NOPR and agrees with 
Scales Industrial Technologies that the method was ambiguous and would 
create results that vary with atmospheric pressure. Further, DOE agrees 
with Jenny Products that it is important to account for ambient 
barometric pressure.
    Specifically, compressors within the scope of this rulemaking all 
use control devices. As a result, the full-load operating pressure is a 
characteristic of each model and remains constant under varying 
atmospheric pressure. This means that the method proposed by DOE would 
result in a pressure ratio that is dependent on the atmospheric 
pressure at which the test is performed. This dependence on atmospheric 
pressure reduces the repeatability of the method.
    To remove the dependence on atmospheric pressure, DOE is adopting a 
revised method for measuring pressure ratio at full-load operating 
pressure in this final rule. This method uses a standard atmospheric 
pressure, 100 kPa, and uses the full-load operating pressure declared 
for the compressor. As a result, this method creates results that are 
independent of the atmospheric pressure at which testing is performed.
9. Maximum Full-Flow Operating Pressure, Full-Load Operating Pressure, 
and Full-Load Actual Volume Flow Rate
    In the test procedure NOPR, DOE proposed a detailed method to 
determine maximum full-flow operating pressure, full-load operating 
pressure, and full-load actual volume flow rate. Specifically, DOE 
proposed that the full-load operating pressure would be a manufacturer-
declared value based on the measured maximum full-flow operating 
pressure. In its proposal, DOE allowed manufacturers to declare a full-
load operating pressure of between 90 percent and 100 percent of the 
maximum full-flow operating pressure. The full-load operating pressure 
would then be used for subsequent testing in order to determine the 
full-load actual volume flow rate, specific power and package 
isentropic efficiency. 81 FR 27220, 27241-27243 (May 5, 2016).
    DOE received many comments related to its proposal that full-load 
operating pressure would be a manufacturer-declared value based on the 
measured maximum full-flow operating pressure, as well as comments 
related to the procedure to determine maximum full-flow operating 
pressure. These comments are discussed in the paragraphs that follow. 
However, DOE received no comments regarding the proposed method to 
determine full-load actual volume flow rate. Consequently,

[[Page 1086]]

for the reasons established in the test procedure NOPR, DOE is adopting 
this method as proposed in the test procedure NOPR.
    Jenny Products commented that the procedure to determine maximum 
full-flow operating pressure was confusing, but did not offer specific 
guidance as to how it could be simplified. (Jenny Products, No. 0020 at 
p. 4) Further, Jenny Products stated that ISO allowed for a tolerance 
of 2 psig for pressure variation vs. the 1 psig 
variation proposed by DOE when determining the maximum full-flow 
operating pressure. DOE would like to clarify that the discharge 
pressure variation tolerance in ISO 1217:2009(E) is 1 
percent from average as specified in 6.2 Table 1. With respect to Jenny 
Products comments regarding the detail of the procedure to determine 
maximum full-flow operating pressure, DOE recognizes that the procedure 
is nuanced, but believes that the detail is necessary to ensure a 
repeatable and reproducible test across all compressors included in the 
scope of this final rule. DOE also notes that the accuracy requirement 
of 1 psig is necessary due to the discrete increments of 
pressure required as discussed in the test procedure NOPR. 81 FR 27220, 
27242 (May 5, 2016). Consequently, DOE adopts the method to determine 
maximum full-flow operating pressure as proposed in the test procedure 
NOPR in this final rule.
    Compressed Air Systems commented that the operating pressure is a 
range, not a static number, and can vary between load and unload 
pressure. (Compressed Air Systems, No. 0008 at p. 2) In response to 
Compressed Air Systems' concern, DOE agrees that compressors may output 
air at a range of pressures. However, DOE must select a specific 
pressure value for manufacturers to use, in order to fairly and 
equitably measure compressor performance.
    In response to DOE's proposal, Atlas Copco objected to 
manufacturers self-declaring full-load operating pressure of between 90 
and 100 percent of maximum full-flow operating pressure, claiming that 
this creates a loophole where fixed-speed machines can select the 
optimal pressure for maximum efficiency (between 90-100 percent), but 
variable-speed units are penalized because all points have to achieve 
efficiencies greater than required by the standard. (Atlas Copco, No. 
0009 at p. 15) In response to Atlas Copco's concern, DOE clarifies that 
manufacturers currently self-declare full-load operating pressure and 
the provision proposed by DOE in the test procedure NOPR allows 
manufacturers to continue this practice. Further, any potential benefit 
to fixed-speed compressors from this self-declaration could be realized 
equally by all fixed-speed compressors and thus not be considered a 
loophole. Additionally, in the energy conservation standards NOPR, DOE 
proposed fixed-speed and variable-speed compressors to be considered in 
separate equipment classes with separate proposed standards. As such, 
any benefits provided to fixed-speed compressors would have no bearing 
on the performance or relative ranking of variable compressors, which 
would be assessed using a completely separate metric and proposed 
standard.
    Atlas Copco also claimed there could be a loophole whereby a 
manufacturer represents the full-load operating pressure at which the 
compressor achieves its optimum efficiency (e.g., 125 psig), but 
markets the product at a different pressure (e.g., 90 psig). To remedy 
these concerns, Atlas Copco suggested any declared full-load operating 
pressure must have an associated efficiency that is above the standard. 
(Atlas Copco, No. 0009 at pp. 15-16) DOE agrees with Atlas Copco that 
rating a compressor at one pressure and marketing a compressor at a 
different pressure is undesirable and believes the provisions of the 
test procedure NOPR are in agreement with Atlas Copco's suggestion. 
Specifically, in the test procedure NOPR, DOE clearly proposed that any 
representation of full-load actual volume flow rate, full-load 
operating pressure, full-load package isentropic efficiency, and part-
load package isentropic efficiency must be made according to the DOE 
test procedure. Given this provision, manufacturers can only self-
declare one full-load operating pressure, and the package isentropic 
efficiency associated with this operating pressure must be represented 
in accordance with the DOE test procedure.
    Scales Industrial Technologies indicated a preference for the 
manufacturer's maximum design pressure at full capacity in response to 
a request for comment regarding the full-load operating pressure. 
(Scales Industrial Technologies, No. 0013 at pp. 7) DOE is unclear as 
to the exact meaning of maximum design pressure at full capacity. 
However, requiring use of an objective maximum pressure (i.e., maximum 
full-flow operating pressure) would force a manufacturer to rate a 
compressor in a manner unfamiliar to customers and, possibly, in a way 
that does not characterize the way the compressor is likely to be 
operated in practice. The 10-percent psig limit proposed in the test 
procedure NOPR balances DOE's need to create a fair and equitable 
rating point while maintaining the flexibility needed for compressor 
manufacturers to continue to meet the needs of their end users.
    CAGI agreed that manufacturers should be allowed to self-declare a 
full-load operating pressure, but suggested a tolerance of either 10 
percent or 10 psi, \35\ whichever is greater. CAGI added that a 10-
percent range would not be practical for lower-pressure equipment. 
(CAGI, No. 0010 at p. 11) DOE interpreted this comment to translate to 
the following requirement:
---------------------------------------------------------------------------

    \35\ Here, there is no difference between absolute and gauge 
pressure.
---------------------------------------------------------------------------

    If measured maximum full-flow operating pressure is greater than 
100 psig, manufacturers would be allowed to declare a full-load 
operating pressure of between 90 percent and 100 percent of the 
measured maximum full-flow operating pressure. If measured maximum 
full-flow operating pressure is less than or equal to 100 psig, 
manufacturers would be allowed to declare a full-load operating 
pressure as a value that is up to 10 psi \36\ less than the measured 
maximum full-flow operating pressure.
---------------------------------------------------------------------------

    \36\ Here, there is no difference between absolute and gauge 
pressure.
---------------------------------------------------------------------------

    CAGI suggested that this is a better approach because the 10 
percent range proposed by DOE would not be practical for low-pressure 
equipment. (CAGI, No. 0010 at p. 11) Sullair and CAGI had previously 
suggested this approach in the June 2016 public meeting. (Sullair, 
Public Meeting Transcript, No. 0016 at p. 105; CAGI, Public Meeting 
Transcript, No. 0016 at p. 105-6)
    The CAGI suggestion would only affect units whose maximum full-flow 
operating pressures are less than 100 psig. For those units, 10 percent 
of the full-operating pressure would be 10 psi \37\ or less. DOE 
concludes that CAGI's recommendation is reasonable, and aligns with 
DOE's intent to create a fair and equitable rating point while 
maintaining the flexibility needed for compressor manufacturers to 
continue to meet the needs of their end users.
---------------------------------------------------------------------------

    \37\ Here, there is no difference between absolute and gauge 
pressure.
---------------------------------------------------------------------------

    Thus, in this final rule DOE adopts CAGI's suggestion that if 
measured maximum full-flow operating pressure is greater than 100 psig, 
manufacturers are allowed to declare a full-load operating pressure of 
between 90 percent and 100 percent of the measured maximum full-flow 
operating pressure; and if measured maximum full-flow operating 
pressure is less than or equal to 100 psig, manufacturers are

[[Page 1087]]

allowed to declare a full-load operating pressure as a value that is up 
to 10 psi \38\ less than the measured maximum full-flow operating 
pressure.
---------------------------------------------------------------------------

    \38\ Here, there is no difference between absolute and gauge 
pressure.
---------------------------------------------------------------------------

    In this test procedure final rule, DOE is adopting a minor 
modification to the starting pressure used in the maximum full-flow 
operating pressure test method. In the test procedure NOPR, DOE 
proposed to start the test by adjusting the backpressure of the system 
so the measured discharge pressure is 90 percent of the expected 
maximum full-flow operating pressure, rounded to the nearest integer, 
in psig. If the expected maximum full-flow operating pressure is not 
known, DOE proposed to adjust the backpressure of the system so that 
the measured discharge pressure is 75 psig. The intent of this 
provision is to ensure that all compressors within the scope of this 
rulemaking can be tested to find maximum full-flow operating pressure, 
even when no expected value is known. As discussed in section III.B, 
the scope of this test procedure is now restricted to compressors with 
full-load operating pressure greater than or equal to 75 psig. To 
achieve the original intent of this provision, the starting discharge 
pressure for this test must be slightly lower than that 90 percent of 
the lowest possible maximum full-flow operating pressure (i.e., 75 
psig). Consequently, it is appropriate to revise the default starting 
discharge pressure to 65 psig.

F. Definition of Basic Model

    In the course of regulating products and equipment, DOE has 
developed the concept of using a ``basic model'' for testing to allow 
manufacturers to group similar equipment to minimize testing burden, 
provided all representations regarding the energy use of compressors 
within that basic model are identical and based on the most 
consumptive, least efficient unit. 76 FR 12422, 12423 (Mar. 7, 
2011).\39\ In that rulemaking, DOE established that manufacturers may 
elect to group similar individual models within the same equipment 
class into the same basic model to reduce testing burden, provided all 
representations regarding the energy use of individual models within 
that basic model are identical and based on the most consumptive unit. 
76 FR 12422, 12423 (Mar. 7, 2011). However, manufacturers group models 
with the understanding that there is increased risk associated with 
such model consolidation, due to the potential for an expanded impact 
from a finding of noncompliance. Consolidation of models within a 
single basic model results in such increased risk because DOE 
determines compliance on a basic model basis. Ibid.
---------------------------------------------------------------------------

    \39\ These provisions allow manufacturers to group individual 
models with essentially identical, but not exactly the same, 
electrical, physical, and functional characteristics that affect 
energy performance characteristics into a basic model to reduce 
testing burden. Under DOE's certification requirements, all the 
individual models within a basic model identified in a certification 
report as being the same basic model must have the same certified 
efficiency rating and use the same test data underlying the 
certified rating. The Compliance Certification and Enforcement final 
rule also establishes that the efficiency rating of a basic model 
must be based on the least efficient or most energy consuming 
individual model (i.e., put another way, all individual models 
within a basic model must be at least as energy efficient as the 
certified rating). 76 FR 12422, 12428-12429 (March 7, 2011).
---------------------------------------------------------------------------

    In keeping with this practice, in the test procedure NOPR, DOE 
proposed a definition of basic model for compressors that defines the 
compressor models on which manufacturers must conduct testing to 
demonstrate compliance with any energy conservation standard for 
compressors, while still enabling manufacturers to group individual 
models to reduce the burden of testing. DOE proposed to establish a 
definition of basic model that is similar to other commercial and 
industrial equipment. Specifically, DOE proposed to define a compressor 
basic model to include all units of a class of compressors manufactured 
by one manufacturer, having the same primary energy source, and having 
essentially identical electrical, physical, and functional (or 
pneumatic) characteristics that affect energy consumption and energy 
efficiency. The requirement of ``essentially identical electrical . . . 
characteristics'' means that models with different compressor motor 
nominal horsepower ratings must be classified as separate basic models. 
81 FR 27220, 27243 (May 5, 2016).
    In response to the test procedure NOPR, DOE received comments 
expressing concern that under the definition of the basic model, small 
changes to certified compressors may require manufacturers to retest or 
perform an AEDM in order to recertify the equipment. Specifically, 
Sullivan-Palatek commented that the substitution of non-standard 
electric motors, controls, or coolers would be a significant burden due 
to the testing that would be required for that compressor. Sullivan-
Palatek further commented that DOE should consider the definition of 
basic model that CAGI currently uses, which permits add-ons and 
alterations to basic packages. Sullivan-Palatek indicated that this 
definition of basic model would allow manufacturers to offer specialty 
products without the burden of certifying each customized compressor as 
a new basic model. (Sullivan-Palatek, No. 0007 at pp. 1, 4; Sullivan-
Palatek, Public Meeting Transcript, No. 0016 at p. 44) Kaeser 
Compressors and Sullair also commented that customers often request 
small changes, particularly at higher compressor capacities, and used 
motor substitutions as the primary example of what may constitute 
additional basic models. (Kaeser Compressors, Public Meeting 
Transcript, No. 0016 at p. 46; Sullair, Public Meeting Transcript, No. 
0016 at p. 131) CAGI stated that the DOE definition of a basic model 
differed from the industry definition of a standard model, which the 
industry uses to represent efficiency. CAGI implied that the difference 
in the interpretation of what constitutes a basic model would cause 
many more compressor models to be tested in order to represent their 
efficiency, which is burdensome to manufacturers. (CAGI, Public Meeting 
Transcript, No. 0016 at p. 125-8) Sullair commented that many non-
standard compressor models exist which include modifications that 
increase the energy consumed by the compressor compared to its basic 
model. (Sullair, Public Meeting Transcript, No. 0016 at p. 113)
    DOE clarifies that changes, such as the use of alternate brand 
components (e.g., motors, filters, drives) trigger the need for a new 
basic model only if the variant no longer has essentially identical 
electrical, physical, and functional (or pneumatic) characteristics 
that affect energy consumption and energy efficiency. In response to 
CAGI's concerns that a greater number of basic models may need to 
represent efficiency in comparison to the industry practice of a 
standard model, DOE believes that changes made to the test 
configuration (see section III.E.3) that are adopted in this final rule 
result in a DOE basic model that more closely aligns with the 
industry's concept of a standard model. However, based on Sullair's 
comment, DOE concludes that some additional basic models (as compared 
to the industry's ``standard models'') are justified, as some models 
exhibit unique efficiency characteristics, and accurate representation 
of equipment efficiency is critical to setting an equitable test 
procedure. Finally, DOE notes that in this final rule it is also 
adopting a provision to allow for the use of an AEDM to alleviate the 
burden of representing the efficiency of basic models that are similar 
in design to a standard compressor, but with modifications to suit an 
application or customer request.

[[Page 1088]]

    Consequently, DOE is adopting in this final rule the definition for 
basic model as proposed in the test procedure NOPR.

G. Sampling Plan for Testing and Alternative Efficiency Determination 
Methods

    DOE must provide test procedures that produce results that reflect 
energy efficiency, energy use, and estimated operating cost of 
industrial equipment during a representative average use cycle. (42 
U.S.C. 6314(a)(2)) These representative values are used when making 
public representations and when determining compliance with prescribed 
energy conservation standards. In the test procedure NOPR, DOE proposed 
two uniform methods for manufacturers to determine representative 
values of energy and cost-related metrics: A statistical sampling plan 
or an alternative efficiency determination method. 81 FR 27220, 27244 
(May 5, 2016). The following sections discuss comments received in 
response to DOE's test procedure NOPR regarding statistical sampling 
and AEDMs.
1. Sampling Plan and Representations
a. Minimum Sample Size
    In the test procedure NOPR, DOE proposed a statistical sampling 
plan that requires a minimum of two units be tested to ensure a basic 
model's compliance. 81 FR 27220, 27244-5 (May 5, 2016). In response to 
the proposed sampling plan, CAGI, Compressed Air Systems, Sullair, and 
Sullivan-Palatek commented that, due to low production volume of some 
compressors models, a minimum of two samples would be impractical to 
test as there is not adequate inventory to meet the sampling 
requirements. (CAGI, No. 0010 at p. 11, Compressed Air Systems, No. 
0008 at p. 2, Sullair, No. 0006 at p. 9; Sullair, Public Meeting 
Transcript, No. 0016 at p. 124; Sullivan-Palatek, Public Meeting 
Transcript, No. 0016 at p. 56) Ingersoll Rand, Sullair, and Sullivan-
Palatek supported CAGI's comments. (Ingersoll Rand, No. 0011 at p. 1; 
Sullair, No. 0006 at p. 1; Sullivan-Palatek, No. 0007 at p. 1) Sullair 
and Sullivan-Palatek further commented that, for customized low volume 
units, they use a mixture of customer acceptance test data and 
estimation rather than testing per the CAGI Performance Verification 
Program. (Sullair, Public Meeting Transcript, No. 0016 at pp. 43; 
Sullivan-Palatek, Public Meeting Transcript, No. 0016 at p. 44) 
Ingersoll Rand commented that testing is performed on every compressor 
package that it produces, but some units are unique and driven by 
customer-specific application requirements. (Ingersoll Rand, Public 
Meeting Transcript, No. 0016 at pp. 44-45)
    In response to the concerns regarding low-volume units, DOE 
understands that within the scope in the test procedure NOPR, certain 
basic models may be produced in low volume and a minimum of two samples 
are impractical to test for these low volume basic models due to 
inadequate inventory availability. However, DOE believes that the 
majority of these low volume units are larger capacity models (i.e., 
models with compressor motor nominal horsepower greater than 200 hp and 
full-load operating pressures greater than 200 psig). As noted in 
section III.B, DOE is limiting the applicability of the test procedure 
established in this final rule to only lubricated compressors with 
compressor nominal motor horsepower of 10 to 200 hp (inclusive) and 
full-load operating pressures of 75 to 200 psig (inclusive). This 
revised scope aligns with the scope recommended by CAGI and other 
manufacturers. Further, the 10 to 200 hp scope established in this 
final rule aligns directly with the scope of the CAGI Performance 
Verification Program for rotary compressors. Manufacturers who 
participate in this program \40\ are required to test multiple basic 
models per year as a part of the program's compliances and 
certification requirements. Basic models are selected at the discretion 
of the CAGI program manager, with the intent of testing through the 
range of eligible products over a period of several years. For each 
basic model selected, manufacturers must make available two individual 
units that are randomly selected from available manufacturer and/or 
distributor stock. Consequently, DOE concludes that the majority of the 
basic models within the scope of the test procedure established by this 
final rule are commonly available (i.e., not low production volume) and 
are typically produced in quantities of at least two units per year.
---------------------------------------------------------------------------

    \40\ The following manufacturers participate in the CAGI Rotary 
Compressor Performance Verification Program according to the 
participant directory: Atlas Copco, Boge, Chicago Pneumatic, 
CompAir, FS Curtis, Gardner Denver, Ingersoll Rand, Kaeser 
Compressors, Mattei, Quincy, Sullair and Sullivan-Palatek. The 
participant directory is available at https://www.cagi.org/performance-verification/.
---------------------------------------------------------------------------

    However, even with the reduced scope established in this test 
procedure final rule, a small number of basic models may still be 
produced in very limited quantities. This limited subset of models may 
be produced in low quantities for a variety of reasons; for example, 
specific customer requirements may lead manufacturers to customize 
existing basic models or produce new, custom compressors, with unique 
performance characteristics. To address the industry's concern 
regarding the testing of low-volume production compressors, DOE 
specifically proposed, in the test procedure NOPR, to allow 
manufacturers to certify the energy efficiency of basic models through 
the use of an AEDM in lieu of physical testing. In such cases, no 
physical testing is required and, therefore, the sample size provisions 
are not applicable. Complete discussion of AEDM is provided in section 
III.G.2, where DOE discusses its rationale for adopting certain AEDM 
provisions in this final rule.
    In summary, DOE concludes that the reduced scope has significantly 
reduced the number of low-production-volume basic models that are 
subject to this test procedure. Further, DOE concludes that the 
allowance of an AEDM in the place of testing sufficiently addresses the 
industry's concern regarding testing the limited number of low-
shipments-volume compressor basic models that remain in scope. DOE also 
notes that relying on a sample size of at least two units is important 
to account for manufacturing variability and test uncertainty. Using a 
sample size of at least two units and the associated statistics 
provides consumers and DOE with reasonable assurance that any 
representative value of package isentropic efficiency or other values 
associated with a given basic model is, in fact, representative of the 
population of units to which that basic model rating applies. For these 
reasons, in this final rule, DOE is adopting a minimum sample size of 
two units, as proposed in the test procedure NOPR.
b. Sampling Statistics
    In the test procedure NOPR, DOE proposed that package isentropic 
efficiency be represented as the lower of (1) the mean of the test 
sample, and (2) the lower 95 percent confidence limit (LCL) divided by 
0.95. 81 FR 27220, 27244-27245 (May 5, 2016). DOE also proposed that 
package specific power, full-load actual volume flow rate, full-load 
operating pressure, and pressure ratio be represented as the mean of 
the test sample. 81 FR 27220, 27244 (May 5, 2016).
    In response to DOE's proposal, CAGI, Ingersoll Rand, and Sullivan-
Palatek commented that the 95 percent lower confidence limit as part of 
the sampling plan results in a more conservative rating than the 
current industry standard. (CAGI, No. 0010 at p. 14; Ingersoll Rand, 
Public Meeting

[[Page 1089]]

Transcript, No. 0016 at pp. 121-2; Sullivan-Palatek, No. 0007 at pp. 2, 
4) CAGI's comments regarding sampling were supported by Sullair. 
(Sullair, No. 0006 at p. 1) CAGI, Ingersoll Rand, and Sullivan-Palatek 
further stated that data published under the CAGI Performance 
Verification Program was not collected using the sampling method 
proposed in the test procedure NOPR (i.e., the lower of the sample mean 
or the 95 percent confidence limit divided by 0.95). They further 
argued that adjustments may be needed to the minimum standard levels 
proposed in the compressors energy conservation standard NOPR, which 
was made with unaltered CAGI Performance Verification Program data, to 
account for the proposed sampling plan. (CAGI, No. 0010 at pp. 15-16; 
Ingersoll Rand, No. 0011 at pp. 1-2; Sullivan-Palatek, No. 0007 at p. 
4) Sullivan-Palatek further commented that the proposed standards, if 
left without adjustment, represented an extra level of performance 
above and beyond the TSL2 standard. (Sullivan-Palatek, No. 0007 at p. 
4)
    In response to commenters' concerns, DOE acknowledges that the 
proposed sampling plan may result in a more conservative rating than 
the current industry standard, as the proposed sampling statistics for 
package isentropic efficiency are designed to account for variability 
in testing and manufacture (as is done with most other covered products 
and equipment). Requiring the use of sampling statistics, rather than 
the sample mean, provides end-users and DOE with reasonable assurance 
that any individual unit distributed in commerce is as efficient, or 
better, than its basic model rating. DOE believes that this assurance 
is beneficial to the end user, and as such rejects the use of the 
sample mean for representations of package isentropic efficiency.
    In the absence of a specific alternative recommendation for package 
isentropic efficiency sampling statistics, DOE adopts the sampling 
statistics plan, as proposed in the test procedure NOPR, in this final 
rule. Specifically, package isentropic efficiency shall be represented 
as the lower of (1) the mean of the test sample, and (2) the lower 95 
percent confidence limit (LCL) divided by 0.95.
    DOE received no comments disagreeing with the test procedure NOPR 
proposal that package specific power, full-load actual volume flow 
rate, full-load operating pressure, and pressure ratio shall be 
represented as the mean of the test sample. Consequently, in this final 
rule, DOE adopts this requirement, as proposed in the test procedure 
NOPR. However, DOE acknowledges that the sampling plan proposed in the 
test procedure NOPR may result in package isentropic efficiency ratings 
that differ from those used in the energy conservation standards NOPR 
analysis. This is because the energy conservation standards analysis 
assumed mean package isentropic efficiency values for each basic model, 
while in practice some basic models may be rated using the lower 95 
percent LCL divided by 0.95. Consequently, in the concurrent energy 
conservation standards final rule, DOE will account for the effect of 
rating using the lower 95 percent LCL divided by 0.95, and adjust the 
analysis and efficiency levels, where applicable.
c. 180-Day Representations Requirement
    EPCA prescribes that all representation of the metrics discussed in 
section III.G.1.b must be made in accordance with DOE test procedures 
and representations requirements, beginning 180 days after publication 
of such a test procedure final rule in the Federal Register. (42 U.S.C. 
6314(d)(1))
    In response to DOE's test procedure NOPR, CAGI commented that the 
adoption of the 180-day effective date is a significant burden that DOE 
did not consider. (CAGI, No. 0010 at pp. 11, 14) These comments were 
echoed by Ingersoll Rand. (Ingersoll Rand, No. 0011 at p. 2; Ingersoll 
Rand, Public Meeting Transcript, No. 0016 at p. 14) Atlas Copco raised 
similar concerns in its comments. (Atlas Copco, No. 0009 at p. 7-10) 
Likewise, Jenny Products commented that it will not be able to comply 
within 180 days and noted that it would need to order test equipment, 
construct an environmental testing room, train employees to conduct 
testing, build compressors, and test compressors. Jenny Products 
indicated that they have over 110,880 different basic models that would 
need to be certified. (Jenny Products, No. 0020 at pp. 4-5) CAGI noted 
that while the proposed full- and part-load package isentropic 
efficiency metric isn't used by the industry nor represented in 
literature, four other metrics (package specific power, full-load 
actual volume flow rate, full-load operating pressure, and pressure 
ratio) are. CAGI further stated that the requirement to review 
literature and verify compliance with the test procedure within 180 
days of publication for these four metrics is unreasonable. (CAGI, No 
0010 at p. 14) Ingersoll Rand, Sullair, and Sullivan-Palatek made 
similar comments as CAGI, with Ingersoll Rand stating that its existing 
compressor data would likely be rendered invalid due to changes in the 
test procedure, and the proposed test procedure would impose 
significant burden to re-evaluate its existing portfolio of products. 
(Ingersoll Rand, No. 0011 at p. 2; Ingersoll Rand, Public Meeting 
Transcript, No. 0016 at pp. 131, 133; Sullair, No. 0006 at pp. 1, 9; 
Sullivan-Palatek, No. 0007 at p. 5) CAGI requested that DOE delay the 
compliance date of the test procedures to coincide with the compliance 
date of any energy conservation standards. CAGI further stated that 
there is ample precedent to support such a delay.\41\ (CAGI, No 0010 at 
p. 15; CAGI, No 0010 at p. 11) Ingersoll Rand and Sullair made similar 
comments with respect to delaying the compliance date of the test 
procedure; Ingersoll Rand specifically commented that the compliance 
date should be delayed to coincide with the energy conservation 
standard. (Ingersoll Rand, No. 0011 at p. 2; Sullair, No. 0006 at p. 9)
---------------------------------------------------------------------------

    \41\ DOE notes that under EPCA, it does not have the authority 
to implement such a delay.
---------------------------------------------------------------------------

    CAGI also commented that aligning the test methods and tolerances 
with current practice would significantly minimize the 180-day burden 
of the sampling plan. (CAGI, No. 0010 at p. 11) Ingersoll Rand and 
Sullair had similar comments to CAGI. Specifically, Sullair stated that 
if the scope of the test procedure was limited to commonly commercial 
units with test procedures that had better alignment with ISO 
1217:2009(E), the burden [of representing efficiency per the proposed 
test procedure within 180 days] would be reduced. (Ingersoll Rand, 
Public Meeting Transcript, No. 0016 at pp. 131, 133; Sullair, Public 
Meeting Transcript, No. 0016 at p. 134)
    Similarly, Atlas Copco stated that the DOE's proposed test 
procedure omits or changes key elements from ISO 1217:2009(E), 
ultimately requiring every manufacturer to retest (or perform an AEDM) 
and rerate every compressor within 180 days, if manufacturers were to 
continue making representations. Atlas Copco also stated that this 
scenario would be unduly burdensome, and recommended that DOE adopt a 
three-year transition rule allowing manufacturers to meet testing and 
modeling requirements with valid data generated under ISO 1217:2009(E). 
Atlas Copco cited case law supporting its recommendation of adoption of 
a three-year transition period, specifically, Center for Biological 
Diversity v. National Highway Traffic Safety Administration,\42\ 538 
F.3d 1172, 1206

[[Page 1090]]

(9th Cir. 2008). (Atlas Copco, No. 0009 at pp. 7-10)
---------------------------------------------------------------------------

    \42\ DOE notes that this case is not pertinent to the regulation 
of industrial equipment under EPCA.
---------------------------------------------------------------------------

    DOE acknowledges Atlas Copco's concerns that its test method, as 
proposed in the test procedure NOPR differed from ISO 1217:2009(E). 
However, as discussed in sections III.B and III.E, in this final rule 
DOE is modifying its NOPR proposal to reduce scope and better align 
with ISO 1217:2009(E). As stated by CAGI, Ingersoll Rand, and Sullair, 
DOE believes that increased alignment with ISO 1217:2009(E) will reduce 
the burden of making representation per the test procedure within 180 
days.
    Regarding comments requesting that DOE extend the 180-day 
representations requirement, DOE reiterates that EPCA prescribes the 
effective date for test procedure representations in 42 U.S.C. 
6314(d)(1) and does not provide DOE with discretion to delay the 
effective date for covered equipment. However, EPCA does provide an 
allowance for individual manufacturers to petition DOE for an extension 
of the 180-day effective date if the manufacturer may experience undue 
hardship as a result of 180-day timeframe provided under 42 U.S.C. 
6314(d)(1). To receive such an extension, petitions must be filed with 
DOE not later than 60 days before the representations are required to 
reflect the DOE test procedure and must detail how the manufacturer 
will experience undue hardship. (42 U.S.C. 6314 (d)(2)) Beyond this 
extension, as noted above, DOE lacks authority to extend the date for 
adjust representations to reflect the DOE test procedure.
    In response to these concerns, DOE notes that EPCA prescribes the 
effective date for test procedure representations in 42 U.S.C. 
6314(d)(1) and does not provide DOE with discretion as to the effective 
date for different equipment. However, to reduce, to the extent 
possible, the potential burden cited by manufacturers, in this final 
rule, DOE is establishing test procedures that are intended to produce 
results equivalent to those produced under ISO 1217:2009(E), as 
amended.\43\ As discussed in section III.E, in this final rule DOE is 
making many modifications to the methods proposed in the test procedure 
NOPR proposal to align as closely as possible to ISO 1217:2009(E), as 
amended. In addition, as discussed in section III.B, DOE is limiting 
the scope of the adopted test procedures to be consistent with 
compressors that currently participate in the CAGI program. As noted by 
CAGI and Sullair, these modifications to align the scope and test 
methods of the test procedures adopted in this final rule with ISO 
1217:2009(E), as amended, mitigate the majority of the commenters' 
concerns. DOE understands that manufacturers of compressors may have 
historical test data that were developed based on ISO 1217:2009(E). If 
historical test data is based on the same methodology being adopted in 
this final rule, then manufacturers may use this data for the purposes 
of representing any metrics subject to the representations 
requirements. Additionally, DOE concludes that Atlas Copco's request 
for a three-year transition rule is no longer pertinent, as the request 
is predicated on the assumption that historical data tested to ISO 
1217:2009(E) does not meet the requirements of the DOE test procedure.
---------------------------------------------------------------------------

    \43\ In this final rule, DOE is incorporating by reference parts 
of ISO 1217:2009(E) as amended by Amendment 1:2016. Amendment 1:2016 
did not introduce any changes in regards to this particular topic, 
so aligning with ISO 1217:2009(E), as amended, is equivalent to 
aligning with ISO 1217:2009(E) prior to Amendment 1:2016.
---------------------------------------------------------------------------

2. Alternative Efficiency Determination Method
    An AEDM is a mathematical model that a manufacturer may validate 
and use to predict the energy efficiency or energy consumption 
characteristics of a basic model. In the test procedure NOPR, DOE 
proposed the use of a validated AEDM as an alternative to testing to 
reduce testing burden. DOE laid out the basic criteria an AEDM must 
satisfy, as well as validation, records retention, enforcement, and 
representations requirements related to AEDMs. 81 FR 27220, 27245-6 
(May 5, 2016).
    Specifically, the test procedure NOPR contained four AEDM 
validation classes, applicable to four varieties of compressor: (1) 
Rotary, fixed-speed; (2) rotary, variable-speed; (3) reciprocating, 
fixed-speed; and (4) reciprocating, variable-speed. DOE also proposed 
that two basic models be tested to validate the AEDM for each 
validation class for which it is intended to be applied. Validation is 
achieved by demonstrating that the results from the mathematical model 
are in agreement with the results obtained from actual testing of the 
requisite number of basic models in accordance with the applicable DOE 
test procedures. In the test procedure NOPR, DOE proposed that the 
AEDM-predicted results for a basic model must be (for energy 
consumption metrics) equal to or greater than 95-percent or (for energy 
efficiency metrics) less than or equal to 105-percent of the tested 
results for that same model for the AEDM results to be valid. 81 FR 
27220, 27245-27246 (May 5, 2016).
    In response to the test procedure NOPR, CAGI commented that the 
representative values for a number of basic models can be predicted 
using computer modeling and prediction techniques based on a single 
common basic package compressor model. As such, CAGI suggested that DOE 
relax the AEDM definition so that testing does not need to be carried 
out on every basic model. (CAGI, No. 0010 at p. 15) Compressed Air 
Systems commented that the use of AEDMs could translate to large 
expenses for small air compressor packagers, as they often do not have 
the necessary staff and software. Compressed Air Systems also stated 
that the specialized nature of small packagers means that most products 
are low-volume and customized, and that the cost to develop an AEDM for 
those products would make it impossible to maintain a competitive 
price. (Compressed Air Systems, No. 0008 at p. 2) CASTAIR commented 
that AEDM modeling would be too large an expense for small air 
compressor assemblers due to the cost in staffing, equipment, and 
facilities. (CASTAIR, No. 0018 at p. 1)
    In response to CAGI's comment, DOE clarifies that the proposed AEDM 
requirements are that a minimum of two basic models be tested for each 
validation class; there is no requirement that all basic models for 
which the AEDM is applicable be tested. That is, while an AEDM may be 
validated for a large number of basic models within a given validation 
class, only two of those basic models need to be tested in accordance 
with the test procedure and related sampling plans to validate the AEDM 
for all basic models in that validation class. DOE believes, therefore, 
that the AEDM requirements, as proposed in the test procedure NOPR, 
already align with CAGI's suggestions and no modification is necessary. 
DOE believes that at least two unique models for each validation class 
must be tested to ensure the broad applicability and accuracy of the 
validated AEDM across the range of basic models to which it may be 
applied.
    With respect to Compressed Air Systems and CASTAIR's comments, DOE 
also notes that AEDMs were proposed as an optional strategy to evaluate 
equipment at a lower cost than physical testing. Under the test 
procedure NOPR proposal, manufacturers may continue to conduct physical 
testing according to the proposed test procedure and sampling plan 
instead of choosing to rate equipment using an AEDM, or both. Thus, 
given the optional nature of the AEDM, DOE does not expect the

[[Page 1091]]

inclusion of AEDMs to result in additional burden to manufacturers. In 
fact, in many cases, use of an AEDM dramatically reduces the cost of 
rating compressor models, as once the AEDM is developed and validated, 
it can be used on any basic model for which it is validated.
    The use of an AEDM may be particularly helpful for customized and/
or low-volume basic models that are rarely manufactured and sold. As 
noted in section III.G.1.a, commenters expressed concern that some 
units are not produced in enough quantity to meet the minimum sample 
size of two units, which makes the application of the test procedures 
impractical. In those cases, use of an AEDM may be a less burdensome 
way to determine the performance data required for representation and 
compliance with any energy conservation standard. With AEDMs, several 
similar models can be accurately evaluated based on test data for only 
a few models, which can greatly reduce the costs associated with 
determining the performance of customized models. Furthermore, AEDMs 
can be validated using test data from commonly available basic models 
and then used to estimate the performance of low-volume units, which 
reduces the cost of testing per unit for low-volume basic models. Thus, 
AEDMs are a convenient option to reduce the testing burden on 
customized equipment and/or equipment with low sales volume.
    Additionally, in response to Compressed Air Systems and CASTAIR's 
specific comments on the burden of test procedures or an AEDM, any test 
procedures or energy conservation standards DOE promulgates must be 
equitable to all industry participants, meaning that all participants, 
regardless of size, must be held to the same testing and energy 
conservation standard criteria. As discussed further in section IV.B, 
DOE analyzed the costs of conducting testing and rating of compressors 
in accordance with the test procedures adopted in this final rule and 
accounted for the costs of such testing on manufacturers, including 
small manufacturers, in its energy conservation standards NOPR 
analysis. 81 FR 31680, 31761 (May 19, 2016). However, as noted in the 
energy conservation standards NOPR, additional compliance flexibilities 
may be available through other means. For example, individual 
manufacturers may petition DOE for a waiver of the applicable test 
procedures. In addition, EPCA provides that a manufacturer whose annual 
gross revenue from all of its operations does not exceed $8,000,000 may 
apply for an exemption from all or part of an energy conservation 
standard for a period not longer than 24 months after the effective 
date of a final rule establishing the standard. Ibid.
    DOE did not receive any specific comments regarding the 
applicability of the AEDM validation tolerances or other AEDM 
requirements proposed in the test procedure NOPR. Accordingly, DOE is 
adopting the AEDM validation requirements proposed in the test 
procedure NOPR. However, due the revised scope of the test procedures 
adopted in this final rule (discussed in section III.B), DOE is 
reducing the number of validation classes from four to two. 
Specifically, DOE is adopting AEDM provisions for rotary fixed-speed 
and rotary variable-speed compressors and removing the validation 
classes of reciprocating fixed-speed and reciprocating variable-speed 
compressors, as the latter are no longer within the scope of 
applicability of this final rule.

H. Enforcement Provisions

    Enforcement provisions govern the process DOE follows when 
performing its own assessment of basic model compliance with standards, 
as described under 10 CFR 429.110. In the test procedure NOPR, DOE 
proposed requirements related to the variability of the enforcement 
sample, as well as the methods it would use to determine full-load 
operating pressure and full-load actual volume flow rate when 
determining compliance for enforcement purposes. 81 FR 27220, 27246-
27247 (May 5, 2016). The following sections discuss interested party 
comments related to the enforcement sampling plan for package 
isentropic efficiency and enforcement testing procedures for full-load 
operating pressure and full-load actual volume flow rate, respectively.
1. Sample Variability for Package Isentropic Efficiency
    In the test procedure NOPR, DOE proposed an enforcement procedure 
in which DOE would evaluate compliance based on the arithmetic mean of 
a sample not to exceed four units. 81 FR 27220, 27246 (May 5, 2016). 
This proposal mirrors the enforcement provisions adopted in the test 
procedure final rule for commercial and industrial pumps. 81 FR 4086 
(Jan. 25, 2016).
    In response to DOE's proposal, CAGI commented that using the sample 
mean for enforcement without considering the standard deviation of the 
sample increases the risk of a finding of noncompliance. (CAGI, No. 
0010 at pp. 12-13) CAGI and Ingersoll Rand also noted that the sampling 
plans in appendices A, B, and C to subpart C of 10 CFR part 429 do 
account for product variability when evaluating compliance for other 
covered products and equipment. (CAGI, No. 0010 at pp. 12-13; Ingersoll 
Rand, Public Meeting Transcript, No. 0016 at p. 140) CAGI recommended 
that DOE not use the arithmetic mean when evaluating compliance during 
an enforcement test, and instead account for product variability in a 
manner similar to appendices A, B, and C to subpart C of 10 CFR part 
429 and in alignment with ISO 1217:2009(E). (CAGI, No. 0010 at p. 13) 
Ingersoll Rand commented that the enforcement procedure should allow 
for a 5-percent tolerance and not use the sample mean, and noted that 
certain other covered products and equipment allow for a tolerance on 
top of the sample mean. (Ingersoll Rand, Public Meeting Transcript, No. 
0016 at pp. 140-141) Sullair and Sullivan-Palatek stated that they 
support CAGI's position relative to sampling and enforcement. (Sullair, 
No. 0006 at p. 9; Sullivan-Palatek, No. 0007 at pp. 1)
    CAGI and Sullair commented that, for low-volume compressors, 
manufacturers may not be able to produce 4 units for the DOE to conduct 
enforcement testing on, because manufacturers may not manufacture four 
units of a given model within a year. (CAGI, No. 0010 at p. 13; 
Sullair, Public Meeting Transcript, No. 0016 at p. 141)
    In response to these comments, DOE is not finalizing an enforcement 
sampling plan in this rule. Because compliance with any standards will 
not be required for 5 years, DOE will engage in a separate rulemaking 
to allow for further comments and input on how DOE should evaluate 
compliance.
2. Full-Load Operating Pressure and Actual Volume Flow Rate
    In the test procedure NOPR, DOE proposed to adopt provisions that 
specify how DOE would determine the full-load operating pressure for 
the purposes of measuring the full-load actual volume flow rate, 
package isentropic efficiency, specific power, and pressure ratio for 
any equipment tested for enforcement purposes. In addition, DOE 
proposed a method for determining the appropriate standard level for 
any tested equipment based on the tested full-load actual volume flow 
rate. Specifically, to verify the full-load operating pressure 
certified by the manufacturer, DOE proposed to perform the same 
procedure proposed for determining the maximum full-flow operating 
pressure of each unit tested,

[[Page 1092]]

except that DOE would begin searching for maximum full-flow operating 
pressure at the manufacturer's certified value of full-load operating 
pressure prior to increasing discharge pressure. As DOE has proposed to 
allow manufacturers to self-declare a full-load operating pressure 
value of between 90 and 100 percent (inclusive) of the measured maximum 
full-flow operating pressure, DOE proposed to compare the measured 
value(s) of maximum full-flow operating pressure from a sample of one 
or more units to the certified value of full-load operating pressure. 
If a sample of more than one units is used, DOE proposed to calculate 
the mean of the measurements. If the certified value of full-load 
operating pressure is greater than or equal to 90 and less than or 
equal to 100 percent of the maximum full-flow operating pressure 
determined through DOE's testing (i.e., within the tolerance allowed by 
DOE in the test procedures), then DOE proposed it would use the 
certified value of full-load operating pressure certified by the 
manufacturer as the basis for determining full-load actual volume flow 
rate, package isentropic efficiency, and other applicable values. 
Otherwise, DOE proposed it would use the maximum full-flow operating 
pressure as the basis for determining the full-load actual volume flow 
rate, package isentropic efficiency, and other applicable values. That 
is, if the certified value of full-load operating pressure is found to 
be valid, DOE proposed it would set the compressor under test to that 
operating pressure to determine the full-load actual volume flow rate, 
package isentropic efficiency, specific power, and pressure ratio in 
accordance with the DOE test procedures. If the certified full-load 
operating pressure is found to be invalid, DOE proposed it would use 
the measured maximum full-flow operating pressure resulting from DOE's 
testing as the basis for determining the full-load actual volume flow 
rate, package isentropic efficiency, specific power, and pressure ratio 
for any tested equipment.
    Similarly, DOE proposed a procedure to verify the full-load actual 
volume flow rate of any certified equipment and determine the 
applicable full-load actual volume flow rate DOE would use when 
determining the standard level for any tested equipment. Specifically, 
DOE proposed to use the full-load actual volume flow rate determined 
based on verification of full-load operating pressure and compare such 
value to the certified value of full-load actual volume flow rate 
certified by the manufacturer. If DOE found the full-load operating 
pressure to be valid, DOE proposed it would use the full-load actual 
volume flow rate determined at the full-load operating pressure 
certified by the manufacturer. If the full-load operating pressure was 
found to be invalid, DOE proposed it would use the actual volume flow 
rate measured at the maximum full-flow operating pressure as the full-
load actual volume flow rate. DOE proposed it would compare the 
measured full-load actual volume flow rate (determined at the 
applicable operating pressure) from an appropriately sized sample to 
the certified value of full-load actual volume flow rate. If the full-
load actual volume flow rate measured by DOE is within the allowances 
of the certified full-load actual volume flow rate specified in Table 
III.4, then DOE proposed it would use the manufacturer-certified value 
of full-load actual volume flow rate as the basis for determining the 
standard level for tested equipment. Otherwise, DOE proposed it would 
use the measured actual volume flow rate resulting from DOE's testing 
when determining the standard level for tested equipment. 81 FR 27220, 
27247 (May 5, 2016).

  Table III.4--Enforcement Allowances for Full-Load Actual Volume Flow
                                  Rate
------------------------------------------------------------------------
                                                             Allowable
                                                          percent of the
Manufacturer certified full-load actual volume flow rate  certified full-
                   (m\3\/s) x 10 -\3\                       load actual
                                                            volume flow
                                                             rate (%)
------------------------------------------------------------------------
0 < and <= 8.3..........................................   7
8.3 < and <= 25.........................................   6
25 < and <= 250.........................................   5
> 250...................................................   4
------------------------------------------------------------------------

    In response, CAGI commented that it agreed with the tolerances DOE 
proposed in Table III.4. However, CAGI disagreed with DOE's proposal to 
continue an enforcement test when a compressor under test is determined 
not to deliver the full-load actual volume flow rate certified by the 
manufacturer (accounting for allowable enforcement deviations). CAGI 
stated that the proposed methodology could, in some cases, allow DOE to 
evaluate compliance of a compressor based on a lower than certified 
full-load actual volume flow rate, and, therefore, a correspondingly 
lower package isentropic efficiency standard level. CAGI stated that 
this is because compressors that do not provide the full-load actual 
volume flow rate certified by the manufacturer may still be deemed 
compliant provided the compressor was compliant with the standard 
determined based on the tested (i.e., lower that the manufacturer-
rated) full-load actual volume flow rate. CAGI suggested this scenario 
is not fair to the users of industry products and recommend that a 
manufacturer that fails to provide the flow that is claimed and 
certified by the manufacturer after taking allowable deviations into 
account be deemed to have failed. (CAGI, No. 0010 at p. 11; CAGI, 
Public Meeting Transcript, No. 0016 at p. 106) Atlas Copco made similar 
comments with respect to testing at a lower volume flow rate and the 
equity of doing so. (Atlas Copco, No. 0009 at p. 18) CAGI's position 
regarding the tolerances and enforcement of full-load actual volume 
flow rate is supported by Sullair, Sullivan-Palatek, and Ingersoll 
Rand. (Sullair, No. 0006 at p. 9; Sullivan-Palatek, No. 0007 at p. 1; 
Ingersoll Rand, No. 0011 at p. 1) DOE received no comments disagreeing 
with the proposed method for determining maximum and full-load 
operating pressure.
    DOE acknowledges the concerns of commenters that allowing 
compressor equipment to be deemed compliant with any applicable 
standards for compressors when the full-load actual volume flow rate is 
below the certified and represented value is unfair to compressor end 
users. DOE typically designs the enforcement provisions to minimize 
risk for manufacturers such that equipment with capacities (i.e., full-
load actual volume flow rates) that differ from the certified values 
may still be deemed compliant based on the tested energy performance 
and a unit is not be deemed non-compliant on the grounds of the tested 
capacity alone. However, given the broad manufacturer support for 
modified enforcement provisions in this case, in this final rule, DOE 
is adopting CAGI and Atlas Copco's recommendation to declare 
compressors with tested full-load actual volume flow rates below the 
certified value non-compliant. Specifically, the certified full-load 
actual volume flow rate will be considered valid only if all 
measurement(s) (either the measured full-load actual volume flow rate 
for a single unit sample or the measured values for each unit in a 
multiple unit sample) are within the percentage of the certified full-
load actual volume flow rate specified in Table III.4. If the 
representative value of full-load actual volume flow rate as tested is 
outside of the allowable tolerances specified in Table III.4, DOE will 
make a

[[Page 1093]]

determination that the basic model is not in compliance with the 
applicable regulations for that model. Specifically, DOE will fail such 
models on the basis of making representations that are not in 
accordance with the test procedure, which is consistent with DOE's 
authority under 42 U.S.C. 6316(a) and 6314(d).
    DOE is also adopting a small modification in the starting pressure 
used when determining maximum full-flow operating pressure during 
enforcement testing. In the test procedure NOPR, DOE stated that 
testing would start at the certified value for full-load operating 
pressure. This starting value, however, creates the possibility that 
units could unload on the first test point, requiring testers to start 
the test again. There are many compressors that have a full-load 
operating pressure equal to their maximum full-flow operating pressure. 
DOE has also been told by an industry testing expert that the cut-out 
controls on compressors can vary by 1 or more psig between units. 
Therefore, starting the test at the certified full-load operating 
pressure creates the potential that the unit under test could unload at 
the starting discharge pressure. To prevent this possibility, DOE is 
adopting a starting point for this method equal to 90 percent of the 
certified full-load operating pressure. This allows the unit to be 
tested at several discharge pressures prior to reaching the range of 
pressures at which it is likely to unload.

IV. Procedural Issues and Regulatory Review

A. Review Under Executive Order 12866

    The Office of Management and Budget (OMB) has determined that test 
procedure rulemakings do not constitute ``significant regulatory 
actions'' under section 3(f) of Executive Order 12866, Regulatory 
Planning and Review, 58 FR 51735 (Oct. 4, 1993). Accordingly, this 
action was not subject to review under the Executive Order by the 
Office of Information and Regulatory Affairs (OIRA) in the Office of 
Management and Budget (OMB).

B. Review Under the Regulatory Flexibility Act

    The Regulatory Flexibility Act (5 U.S.C. 601 et seq., as amended by 
the Small Business Regulatory Enforcement Fairness Act of 1996) 
requires preparation of an initial regulatory flexibility analysis 
(IRFA) for any rule that by law must be proposed for public comment and 
a final regulatory flexibility analysis (FRFA) for any such rule that 
an agency adopts as a final rule, unless the agency certifies that the 
rule, if promulgated, will not have a significant economic impact on a 
substantial number of small entities.
    A regulatory flexibility analysis examines the impact of the rule 
on small entities and considers alternative ways of reducing negative 
effects. Also, as required by Executive Order 13272, ``Proper 
Consideration of Small Entities in Agency Rulemakings,'' 67 FR 53461 
(August 16, 2002), DOE published procedures and policies on February 
19, 2003, to ensure that the potential impacts of its rules on small 
entities are properly considered during the DOE rulemaking process. 68 
FR 7990. DOE has made its procedures and policies available on the 
Office of General Counsel's Web site at: https://energy.gov/gc/office-general-counsel. As part of the test procedure NOPR published on May 5, 
2016 (81 FR 27220), DOE concluded that the cost effects accruing from 
the final rule would not have a ``significant economic impact on a 
substantial number of small entities,'' and that the preparation of a 
FRFA is not warranted. DOE has submitted a certification and supporting 
statement of factual basis to the Chief Counsel for Advocacy of the 
Small Business Administration for review under 5 U.S.C. 605(b).
    DOE reviewed this rule, which establishes a new test procedure for 
compressors, under the provisions of the Regulatory Flexibility Act and 
the procedures and policies published on February 19, 2003.
    DOE certifies that the adopted rule does not have a significant 
impact on a substantial number of small entities. DOE notes that 
certification of compressor models is not currently required because 
energy conservation standards do not currently exist for compressors. 
That is, any burden associated with testing compressors in accordance 
with the requirements for this test procedure will not be required 
until the promulgation of any energy conservation standards for 
compressors. On this basis, DOE maintains that the test procedure final 
rule has no incremental burden associated with it and a FRFA is not 
required.
1. Description and Estimate of the Number of Small Entities Affected
    For the compressors manufacturing industry, the Small Business 
Administration (SBA) has set a size threshold, which defines those 
entities classified as small businesses for the purpose of the statute. 
DOE used the SBA's size standards to determine whether any small 
entities are be required to comply with the rule. The size standards 
are codified at 13 CFR part 121. The standards are listed by North 
American Industry Classification System (NAICS) code and industry 
description and are available at: https://www.sba.gov/sites/default/files/files/Size_Standards_Table.pdf. Compressor manufacturers are 
classified under NAICS 333912, ``Air and Gas Compressor 
Manufacturing.'' The SBA sets a threshold of 1,000 employees or less 
for an entity to be considered as a small business for this category.
    To estimate the number of small business manufacturers of equipment 
applicable to this rulemaking, DOE conducted a market survey using 
available public information. DOE's research involved industry trade 
association membership directories (including CAGI), individual company 
and online retailer Web sites, and market research tools (e.g., Hoovers 
reports) to create a list of companies that manufacture products 
applicable to this rulemaking. DOE presented its list to manufacturers 
in MIA interviews and asked industry representatives if they were aware 
of any other small manufacturers during manufacturer interviews and at 
DOE public meetings. DOE reviewed publicly available data and contacted 
select companies on its list, as necessary, to determine whether they 
met the SBA's definition of a small business manufacturer. DOE screened 
out companies that do not offer products applicable to this rulemaking, 
do not meet the definition of a small business, or are foreign-owned 
and operated.
    DOE identified a total of 40 manufacturers of applicable air 
compressor products sold in the United States. Nineteen of these 
manufacturers met the 1,000-employee threshold defined by the SBA to 
qualify as a small business, but only 15 were domestic companies. Seven 
domestic small businesses manufacture rotary air compressors.
    Within the air compressor industry, manufacturers can be classified 
into two categories; original equipment manufacturers (OEMs) and 
compressor packagers. OEMs manufacture their own air-ends and assemble 
them with other components to create complete package air compressors. 
Packagers assemble motors and other accessories with air-ends purchased 
from other companies, resulting in a complete air compressor.
    Within the rotary air compressor industry, DOE identified 22 
manufacturers; 16 are OEMs and seven are packagers of compressors. Of 
the 22 total manufacturers, seven large OEMs supply approximately 80 
percent of shipments and revenues. Of the seven domestic small rotary 
air compressor

[[Page 1094]]

businesses identified, DOE's research indicates that two are OEMs and 
five are packagers.
2. Discussion of Testing Burden and Comments
a. Burden Related to Test Method and Retesting Equipment for 
Representations
    In the test procedure NOPR, DOE stated that ISO 1217:2009(E) is an 
appropriate industry testing standard for evaluating compressor 
performance, with the caveat that ISO 1217:2009(E) is written as a 
customer acceptance test, and as such it required several modifications 
and additions in order to provide the specificity and repeatability 
required by DOE. Consequently, DOE proposed several modifications and 
additions to ISO 1217:2009(E) and proposed to incorporate by reference 
only the sections of ISO 1217:2009(E) that are relevant to the 
equipment within the scope of applicability of DOE's proposed test 
procedures. DOE stated that by proposing to incorporate by reference 
much of ISO 1217:2009(E) into the proposed DOE test procedures, DOE 
believed that the resulting DOE test procedures would remain closely 
aligned with existing and widely used industry procedures and limit the 
testing burden on manufacturers. 81 FR 27220, 27236-27237 (May 5, 
2016).
    DOE received many comments regarding the burden imposed by DOE's 
proposed test procedures. Many of these comments argued that DOE's 
proposed modifications and additions to ISO 1217:2009(E) were 
materially significant, such that historical test data obtained under 
ISO 1217:2009(E) could no longer be used for representation purposes. 
As a result, the comments stated that manufacturers would be required 
to retest all equipment if they wanted to continue making public 
representations of package specific power, full-load actual volume flow 
rate, full-load operating pressure and pressure ratio.
    Specifically, CAGI, Atlas Copco, Ingersoll Rand, Sullair, and 
Sullivan-Palatek commented that the proposed rule includes 
modifications to the CAGI Performance Verification Program which, 
coupled with the 180-day effective compliance date of the proposed test 
procedures, presents a significant burden for manufacturers to verify 
compliance in their efficiency and non-efficiency representations. 
(CAGI, No 0010 at pp. 11, 14; Ingersoll Rand, No. 0011 at p. 2; Atlas 
Copco, No. 0009 at pp. 7-10; Sullair, No. 0006 at pp. 1, 9; Sullivan-
Palatek, No. 0007 at pp. 5)
    In response to the 2012 NOPD, CAGI commented that ``test procedures 
for measuring the energy efficiency, energy use, or estimated annual 
operating cost of compressors during a representative average use cycle 
or period of use would be unduly burdensome or impossible to conduct,'' 
and that ``there would also be a cost impact to the users for this, 
which would place heavier financial burdens, especially on small 
business users.'' (Docket No. EERE-2012-BT-DET-0033, CAGI, No. 0003 at 
p. 6)
    However, in response to the more recent 2016 test procedure NOPR, 
CAGI commented that if the test methods and tolerances are aligned with 
current practice, the burden of the sampling plan will be significantly 
minimized. (CAGI, No. 0010 at p. 11)
    CASTAIR and Compressed Air Systems commented that the proposed 
regulations will force CASTAIR and other small businesses out of the 
rotary screw market. (CASTAIR, No. 0018 at p. 1; Compressed Air 
Systems, No. 0008 at p. 2) Compressed Air Systems stated that the test 
method would require large investments, which would be in excess of 
their annual sales volume, represent a higher per-unit cost due to 
their low volume of shipments compared to large manufacturers, and take 
a longer time to recover the cost of investing test equipment, placing 
small businesses at a competitive disadvantage relative to large 
manufacturers. (Compressed Air Systems, No. 0008 at pp. 2, 4-5; 
Compressed Air Systems, Public Meeting Transcript, No. 0016 at p. 143) 
Similarly, Jenny Products commented that the cost of compliance, 
including test facilities or the cost of independent lab testing, would 
bankrupt their small business and is unduly burdensome. (Jenny 
Products, No. 0020 at pp. 1, 3) Further, Jenny Products asserted that 
the test procedure is complicated and primarily developed by CAGI 
members, which unfairly burdens non-CAGI members and small businesses 
that can't afford to test their equipment. (Jenny Products, No. 0020 at 
pp. 2, 4-5)
    DOE acknowledges the commenters' general concerns that the test 
procedures, as proposed in the test procedure NOPR, differed enough 
from ISO 1217:2009(E) that, if adopted, manufacturers may need to 
retest all units in order to continue making representations. However, 
DOE reiterates that, as stated in the test procedure NOPR, DOE's intent 
is to propose test procedures that remain closely aligned with existing 
and widely used industry procedures and limit testing burden on 
manufacturers.
    In response to the commenters' concerns, in this final rule, DOE is 
making many modifications to the methods proposed in the test procedure 
NOPR, in order to align as closely as possible to ISO 1217:2009(E), as 
amended.\44\ A complete discussion of these modifications is found in 
section III.E of this final rule. With these modifications, the test 
methods established in the final rule are intended to produce results 
equivalent to those produced historically under ISO 1217:2009(E). 
Consequently, if historical test data are consistent with values that 
are generated when testing with the test methods established in this 
final rule, then manufacturers may use this data for the purposes of 
representing any metrics subject to representations requirements. (DOE, 
Public Meeting Transcript, No. 0016 at p. 136)
---------------------------------------------------------------------------

    \44\ In this final rule, DOE is incorporating by reference parts 
of ISO 1217:2009(E) as amended by Amendment 1:2016. Amendment 1:2016 
did not introduce any changes in regards to this particular topic, 
so aligning with ISO 1217:2009(E), as amended, is equivalent to 
aligning with ISO 1217:2009(E) prior to Amendment 1:2016.
---------------------------------------------------------------------------

    However, DOE acknowledges that current representations for some 
models may not be based on test data or may be based on test data that 
is not in alignment with the test methods established in this final 
rule. DOE agrees that for those models, further testing or the 
application of an AEDM may be needed to continue making 
representations. However, DOE also notes that such representations are 
voluntary and if manufacturers require longer than 180 days to 
determine accurate represented values consistent with the adopted test 
procedure, the manufacturer may elect to not make public 
representations of standardized metrics until such testing is 
completed.
    At this time, DOE does not have direct data regarding how many 
models require further testing or application of an AEDM, however, DOE 
estimates that this is a small percentage of total models. 
Specifically, DOE estimates that 90 percent of models within the scope 
of this test procedure final rule participate in the CAGI Performance 
Verification Program. All members of the CAGI Performance Verification 
Program must represent the performance of all of their models (within 
the scope of the program) based on ISO 1217:2009(E) testing. Thus, DOE 
believes it is fair to assume that the vast majority of models 
participating in the CAGI Performance Verification Program have 
historical ISO 1217:2009(E) test data available, which DOE believes is 
consistent with any values that generated by the test procedure adopted 
in this final rule. DOE acknowledges that the remainder of the models 
(i.e.,

[[Page 1095]]

those not participating in the CAGI Performance Verification Program), 
approximately 15 percent, may not have historical test data available. 
However, DOE reviewed publically available marketing data from all 
known manufacturers that do not participate in the CAGI Performance 
Verification Program and found none of these manufacturers currently 
represent package isentropic efficiency, package specific power, full-
load actual volume flow rate, full-load operating pressure, or pressure 
ratio at full-load operating pressure for compressors within the scope 
of this test procedure final rule. As such, these manufacturers incur 
no burden as a direct result of this test procedure final rule, as they 
are not required to make any representations until the effective date 
of any relevant future energy conservation standards.\45\
---------------------------------------------------------------------------

    \45\ DOE accounts for mandatory testing burden for compressors 
in the energy conservation standards analyses.
---------------------------------------------------------------------------

    In summary, DOE concludes that the test procedures and associated 
representations requirements established in this test procedure final 
rule are not unduly burdensome, as (1) the test method follows accepted 
industry practice, and (2) only a limited number of models (if any) 
may, at the manufacturer's discretion, need to be retested in order to 
continue to make representations. Further DOE notes that impact to each 
manufacturer will be different, and manufactures may petition DOE for 
an extension of the 180-day representations requirement, for up to an 
additional 180 days, if manufacturers feel it represents an undue 
hardship. (42 U.S.C. 6314 (d)(2)) However, as any representations are 
voluntary prior to the compliance date of any energy conservations 
standards for compressors that may be set, there is no direct burden 
associated with any of the testing requirements established in this 
final rule. As such, specific quantification of the burden associated 
with testing and rating equipment to comply with any energy 
conservation standards is addressed in the associated compressors 
energy conservation standard rulemaking manufacturer impact analysis 
(Docket No. EERE-2013-BT-STD-0040).
b. Burdens Related to Low Shipment-Volume Equipment
    In the test procedure NOPR, DOE proposed a scope of applicability 
of compressors that meet the following criteria:
     Are air compressors;
     are rotary or reciprocating compressors;
     are driven by a brushless electric motor;
     are distributed in commerce with a compressor motor 
nominal horsepower greater than or equal to 1 and less than or equal to 
500 hp; and
     operate at a full-load operating pressure of greater than 
or equal to 31 and less than or equal to 225 pounds per square inch 
gauge; 81 FR 27220, 27224-27225 (May 5, 2016).
    In response to the test procedure NOPR, many interested parties 
commented that DOE's proposed scope would capture many low-shipment 
volume or ``custom'' compressor models, and the requirement to test 
such models would cause undue burden.
    Specifically, Atlas Copco stated that the test procedures would 
result in duplicative testing for custom units, because custom units 
already undergo customer acceptance tests based on ISO 1217:2009(E). 
Atlas Copco also commented that an AEDM would not alleviate the burden 
because it requires validation through testing. Atlas Copco further 
recommended that DOE establish a de minimis rule exempting small volume 
(fewer than 20 units per year), customized orders from the test 
requirements in order to avoid unduly burdensome testing requirements. 
(Atlas Copco, No. 0009 at pp. 6-7) Compressed Air Systems stated that 
the requirement to test two units of custom models that are only sold 
once 2 or 3 years will add undue cost, causing many manufacturers to 
stop production of low-shipment-volume models. (Compressed Air Systems, 
No. 0008 at p. 2) CAGI stated that manufacturers cannot build four 
units of all basic models for the purposes of DOE enforcement. 
Considering the definition of a basic model, CAGI expects that many 
basic models will rarely be sold, and it would be impractical to build 
those units only for testing purposes. (CAGI, No. 0010 at p. 13)
    Sullair commented that it would be a burden to test or model all of 
its basic units as the company has more than 500 basic models in the 
range proposed by DOE for the test procedures, most of which are not 
high-volume products. (Sullair, No. 0006 at p. 9) Sullair elaborates 
that a number of those low-volume basic models are above 200 hp, which 
would be a significant burden to test per proposed test procedures and 
would likely result in Sullair ceasing to represent efficiency metrics 
for those units. Sullairs comment is supported by comments made by 
Sullivan-Palatek. (Sullair, No. 0006 at pp. 3-4; Sullivan-Palatek, No. 
0007 at p. 3)
    In response to these comments, DOE acknowledges the commenter's 
concerns that the scope of the test procedure, as defined in the test 
procedure NOPR includes many low-shipment volume or custom compressor 
models, and the requirement to test such models could cause significant 
burden. Therefore in this final rule, DOE is taking two key steps to 
address commenters' concerns and reduce the burden of testing, 
especially for low-volume equipment: (1) DOE is significantly limiting 
the scope of this final rule, as compared to the scope proposed in the 
test procedure NOPR, and (2) DOE is allowing the use of an AEDM, in 
lieu of testing. As discussed in section III.B, the scope of this test 
procedure final rule is limited to compressors that meet the following 
criteria:
     Are air compressors;
     are rotary compressors;
     are not liquid ring compressors;
     are driven by a brushless electric motor;
     are lubricated compressors;
     have a full-load operating pressure of 75-200 psig;
     are not designed and tested to the requirements of The 
American Petroleum Institute standard 619, ``Rotary-Type Positive-
Displacement Compressors for Petroleum, Petrochemical, and Natural Gas 
Industries;'' and
     have a capacity that is either:
    [cir] 10-200 compressor motor nominal horsepower (hp), or
    [cir] 35-1,250 full-load actual volume flow rate (cfm).
    This revised scope generally aligns with the scope recommended by 
CAGI and supported by many manufacturers. Further, the 10 to 200 hp 
scope established in this final rule falls within the scope of the CAGI 
Performance Verification Program for rotary compressors. Manufacturers 
who participate in this program are required to test multiple basic 
models per year as a part of the program's compliances and 
certification requirements. Basic models are selected at the discretion 
of the CAGI program manager, with the intent of testing the range of 
eligible products over a period of several years. For each basic model 
selected, manufacturers must make available two individual units that 
are randomly selected from available manufacturer and/or distributor 
stock. Consequently, DOE concludes that the majority of the basic 
models within the scope of the test procedure established by this final 
rule are commonly available (i.e., not low production volume) and are 
typically

[[Page 1096]]

produced in quantities of at least two units per year.
    However, even with the reduce scope established in this test 
procedure final rule, a small number of basic models may still be 
produced in very limited quantities. To address the industry's concern 
regarding the testing of low-volume production compressors, DOE 
specifically proposed, in the test procedure NOPR, to allow 
manufacturers to certify the energy efficiency of basic models through 
the use of an AEDM in lieu of physical testing. In such cases, no 
physical testing is required and, therefore, the sample size provisions 
are not applicable. Complete discussion of AEDM is provided in section 
III.G.2, where DOE discusses its rationale for adopting certain AEDM 
provisions in this final rule.
    In summary, DOE concludes that the reduced scope has significantly 
reduced the number of low-production-volume basic models that are 
subject to this test procedure. Further DOE concludes that the 
allowance of an AEDM in the place of testing sufficiently addresses the 
industry's concern regarding testing the limited number of low-
shipments-volume compressor basic models that remain in scope. For 
these reasons, DOE concludes that the test procedures and associated 
representations requirements established in this final rule are not 
unduly burdensome.
    Further, the concerns raised by Atlas Copco, which lead them to 
request a de minimis rule exempting small volume custom orders, have 
been mitigated by the scope limitations and allowance for AEDMs 
discussed earlier in this section. However, DOE further clarifies that 
any test procedures it promulgates must be equitable to all industry 
participants, meaning that all participant and regulated equipment must 
be held to the same testing criteria, regardless of manufacturer size 
or physical location. However, DOE reiterates that no direct burden is 
associated with this test procedure final rule until the compliance 
date of any energy conservation standard for compressors that may be 
set and any direct quantification of testing burdens are calculated as 
part of that rulemaking. (Docket No. EERE-2013-BT-STD-0040)
    Finally, regarding CAGI's comment regarding a sample size of up to 
four units for enforcement testing, DOE is not finalizing an 
enforcement sampling plan in this rule. Because compliance with any 
standards will not be required for 5 years, DOE will engage in a 
separate rulemaking to allow for further comments and input on how DOE 
should evaluate compliance.
c. Comments on the NOPR Regulatory Flexibility Analysis
    In the test procedure NOPR, DOE preliminarily concluded that the 
proposed test procedures do not represent a significant incremental 
burden for any of the identified small entities.
    In response to DOE's request for comment, Compressed Air Systems 
provided an additional 16 names of domestic small manufacturers 
producing equipment within the scope of this rulemaking. (Docket No. 
EERE-2013-BT-STD-0040, Compressed Air Systems, No. 0061, pp. 3-4) Upon 
further research, DOE concluded that one of the sixteen entities 
produces equipment within the scope of this rulemaking and added that 
entity to its list of domestic small manufacturers producing equipment 
within the scope of this rulemaking.
    In response to DOE's conclusions, Compressed Air Systems stated 
that small businesses will be uniquely burdened by the test procedures 
because they will now have to test their products, leading to costs 
associated with large in-house test areas, additional employees, and 
electricity costs. (Compressed Air Systems, No. 0008 at p. 2; 
Compressed Air Systems, No. 0008, p. 3) Furthermore, it stated that the 
testing cost per unit would be significantly higher for smaller 
suppliers. CASTAIR commented that the proposed regulations will force 
it to abandon the market and requested that DOE exempt American air 
compressor assemblers from regulation. (CASTAIR, No. 0018, pp. 1-2) 
Both CASTAIR and Compressed Air Systems stressed that testing costs 
would not be alleviated through use of AEDM as such practices are not 
currently used. (CASTAIR, No. 0018, p. 1; Compressed Air Systems, No. 
0008, p. 2)
    DOE acknowledges the concerns raised by CASTAIR and Compressed Air 
Systems. Fundamentally, DOE reiterates, as noted in the test procedure 
NOPR, that the promulgation of test procedures alone, in the absence of 
existing energy conservation standards, does not require a manufacturer 
to perform any certification testing. As such, the burden associated 
with compliance testing will be assessed in the weighing of costs and 
benefits of the associated energy conservation standards rulemaking for 
compressors. However, DOE recognizes that an energy conservation 
standard rulemaking from compressors is ongoing and may result in 
standards and associated certification requirements for certain 
compressors in the near future. Therefore, DOE has considered the 
burden associated with the testing and rating requirements adopted in 
this final rule and, to the extent possible, has sought to minimize 
burden on manufacturers while ensuring that the test procedures adopted 
herein result in consistent, reliable, and repeatable values. Financial 
burden stemming from these DOE test procedures can be discussed in two 
general categories: (1) Aggregates costs of testing in order to 
continue representing standardized metrics that are now specified in 
the DOE test procedures, and (2) the per-unit cost of testing to the 
specified DOE test method.
    Regarding the first cost category, DOE researched public literature 
of the identified small manufacturers and found that seven of the eight 
currently do not make representations of package specific power, full-
load actual volume flow rate, full-load operating pressure, and 
pressure ratio at full-load operating pressure. None make 
representations of package isentropic efficiency. Those that do not 
make representations of these metrics are not expected to incur burden, 
as they can continue to not make representations of these metrics after 
promulgation of this test procedure final rule. As noted above, the 
certification burden is associated with the energy conservation 
standard and will be assessed as part of that rulemaking (Docket No. 
EERE-2013-BT-STD-0040).
    Further, the one small manufacturer making representations of 
package specific power, full-load actual volume flow rate, full-load 
operating pressure, and pressure ratio at full-load operating pressure 
does so as a part of the CAGI Performance Verification Program, which 
relies on ISO 1217:2009(E) test data. As discussed previously, the test 
methods established in this final rule are intended to produce results 
equivalent to those produced historically under ISO 1217:2009(E), as 
amended. Consequently, if historical test data meet the requirements of 
the test methods established in this final rule, then manufacturers may 
use these data for the purposes of representing any metrics subject to 
representations requirements. (DOE, Public Meeting Transcript, No. 0016 
at p. 136) Thus, DOE expects that this manufacturer will incur burdens 
no different from other manufacturers participating in the CAGI 
Performance Verification Program.
    Regarding the second cost category, the per-unit cost of testing to 
the specified DOE test method, DOE reiterates that the test methods 
established in this final rule are based on the industry accepted test 
method,

[[Page 1097]]

ISO 1217:2009(E), as amended, and intended to produce results 
equivalent to those produced historically under ISO 1217:2009(E).\46\ 
As such, DOE concludes that the method itself is not overly burdensome 
as it is currently employed by the many manufacturers who participate 
in the CAGI program.\47\ However, DOE acknowledges the commenters' 
concerns that testing may be more costly and burdensome for small 
manufacturers, as they may not have in-house test facilities. In the 
energy conservation standards NOPR, DOE assessed the per-unit cost to 
test compressors for compliance, and concluded that the industry 
average cost was $2,400 for a fixed-speed rotary compressor, and $3,025 
for a variable-speed compressor. (see chapter 12 of TSD \48\) These 
costs represent industry-average values (i.e., a mix of in-house and 
third-party testing costs) and were based on data gathered during 
confidential manufacturer interviews. Based on these data, DOE 
estimates that third party testing costs approximately 50 percent more 
than the stated industry-average values (i.e., $3,600 for fixed-speed 
and $4,538 for variable-speed compressors).\49\ Although most small 
manufacturers incur testing costs in this higher range, some larger 
manufacturers may also incur similar third party testing costs. Given 
these costs, DOE again, acknowledges that that testing may be more 
costly small manufacturers.
---------------------------------------------------------------------------

    \46\ In this final rule, DOE is incorporating by reference parts 
of ISO 1217:2009(E) as amended by Amendment 1:2016. Amendment 1:2016 
did not introduce any changes in regards to this particular topic, 
so aligning with ISO 1217:2009(E), as amended, is equivalent to 
aligning with ISO 1217:2009(E) prior to Amendment 1:2016.
    \47\ The following manufacturers participate in the CAGI Rotary 
Compressor Performance Verification Program according to the 
participant directory: Atlas Copco, Boge, Chicago Pneumatic, 
CompAir, FS Curtis, Gardner Denver, Ingersoll Rand, Kaeser 
Compressors, Mattei, Quincy, Sullair and Sullivan-Palatek. The 
participant directory is available at https://www.cagi.org/performance-verification/.
    \48\ Available at: https://www.regulations.gov/document?D=EERE-2013-BT-STD-0040-0037.
    \49\ Third party testing is readily available in North America 
and one site is currently used by the CAGI Performance Verification 
Program.
---------------------------------------------------------------------------

    Finally, in response to CASTAIR's recommendation that DOE exempt 
American air compressor assemblers from regulation, DOE clarifies that 
any test procedure it promulgates must be equitable to all industry 
participants, meaning that all participant and regulated equipment with 
in an equipment class must be held to the same testing criteria, 
regardless of shipments volume or the nature of a shipment order.
    Based on its research and discussions presented in this section, 
DOE concludes that the cost burdens accruing from the compressors test 
procedure final rule do not constitute ``significant economic impact on 
a substantial number of small entities.''

C. Review Under the Paperwork Reduction Act of 1995

    While there are currently no energy conservation standards for 
compressors, DOE recently published a final determination establishing 
compressors as a type of covered equipment. 81 FR 79991 (Nov. 15, 
2016). DOE is also considering establishing energy conservation 
standards for such equipment as part of a parallel rulemaking (Docket 
No. EERE-2013-BT-STD-0040). Manufacturers of compressors will be 
required to certify to DOE that their equipment complies with any 
applicable energy conservation standards, once established. To certify 
compliance, manufacturers must first obtain test data for their 
products according to the DOE test procedures for compressors and 
maintain records of that testing for a period of two years after 
discontinuing the product, consistent with the requirements of 10 CFR 
429.71. As part of this test procedure final rule, DOE is establishing 
regulations for recordkeeping requirements for compressors. The 
collection-of-information requirement for the certification (to be 
finalized in a separate rulemaking) and recordkeeping is subject to 
review and approval by OMB under the Paperwork Reduction Act (PRA). 
This requirement has been approved by OMB under OMB control number 
1910-1400. Public reporting burden for the certification and 
recordkeeping requirement is estimated to average 30 hours per 
response, including the time for reviewing instructions, searching 
existing data sources, gathering and maintaining the data needed, and 
completing and reviewing the collection of information.
    Notwithstanding any other provision of the law, no person is 
required to respond to, nor shall any person be subject to a penalty 
for failure to comply with, a collection of information subject to the 
requirements of the PRA, unless that collection of information displays 
a currently valid OMB Control Number.
    CAGI stated that, based on its members' experience with its 
Performance Verification Program, the recordkeeping burden estimate (30 
hours/year) is too low. CAGI also stated that complying with the 
recordkeeping requirements would entail significant development of 
procedures, recordkeeping, quality control measures, etc. (CAGI, No. 
0010 at p. 13) Sullair fully supported CAGI's comments on 
recordkeeping. (Sullair, No. 0006 at p. 9) Ingersoll Rand stated that 
it would need two or three employees for a period of 12 months in order 
to sample, re-test and evaluate their units according to the 
requirements of the proposed test procedure. Ingersoll Rand also stated 
that additional staff would be needed indefinitely to comply with the 
recordkeeping requirements of the proposed rule. (Ingersoll Rand, No. 
0011 at p. 2) Jenny Products commented that the recordkeeping 
requirements are burdensome. (Jenny Products, No. 0020 at p. 5)
    DOE understands that the recordkeeping requirements may vary 
between manufacturers, and that in some cases the recordkeeping burden 
may be greater than estimated. However, DOE has not received any data 
to support the claim that the average recordkeeping burden is greater 
than it estimated. Without data to support an update to its estimate, 
DOE cannot review that estimate. The burden discussed in this section 
relates only to the development and retention of test records and 
development and submission of certification paperwork; it does not 
address the burden of conducting the test procedure, itself, which is 
addressed elsewhere in this rule. Therefore, in this final rule DOE 
does not adjust the recordkeeping burden estimate in the test procedure 
NOPR.

D. Review Under the National Environmental Policy Act of 1969

    In this final rule, DOE establishes a new test procedure that it 
expects will be used to develop and implement future energy 
conservation standards for compressors. DOE has determined that this 
rule falls into a class of actions that are categorically excluded from 
review under the National Environmental Policy Act of 1969 (42 U.S.C. 
4321 et seq.) and DOE's implementing regulations at 10 CFR part 1021. 
Specifically, this final rule creates a new test procedure without 
affecting the amount, quality or distribution of energy usage, and, 
therefore, does not result in any environmental impacts. Thus, this 
rulemaking is covered by Categorical Exclusion A6 under 10 CFR part 
1021, subpart D, which applies to any rulemaking that creates a new 
rule without changing the environmental effect of that rule. 
Accordingly, neither an environmental assessment nor an environmental 
impact statement is required.

[[Page 1098]]

E. Review Under Executive Order 13132

    Executive Order 13132, ``Federalism,'' 64 FR 43255 (August 4, 
1999), imposes certain requirements on agencies formulating and 
implementing policies or regulations that preempt State law or that 
have Federalism implications. The Executive Order requires agencies to 
examine the constitutional and statutory authority supporting any 
action that would limit the policymaking discretion of the States and 
to carefully assess the necessity for such actions. The Executive Order 
also requires agencies to have an accountable process to ensure 
meaningful and timely input by State and local officials in the 
development of regulatory policies that have Federalism implications. 
On March 14, 2000, DOE published a statement of policy describing the 
intergovernmental consultation process it will follow in the 
development of such regulations. 65 FR 13735. DOE examined this final 
rule and determined that it will not have a substantial direct effect 
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. EPCA governs and prescribes Federal 
preemption of State regulations as to energy conservation for the 
products that are the subject of this final rule. States can petition 
DOE for a waiver of Federal preemption to the extent, and based on 
criteria, set forth in EPCA. (42 U.S.C. 6297(d) 6316(a)) No further 
action is required by Executive Order 13132.

F. Review Under Executive Order 12988

    Regarding the review of existing regulations and the promulgation 
of new regulations, section 3(a) of Executive Order 12988, ``Civil 
Justice Reform,'' 61 FR 4729 (Feb. 7, 1996), imposes on Federal 
agencies the general duty to adhere to the following requirements: (1) 
Eliminate drafting errors and ambiguity; (2) write regulations to 
minimize litigation; (3) provide a clear legal standard for affected 
conduct rather than a general standard; and (4) promote simplification 
and burden reduction. Section 3(b) of Executive Order 12988 
specifically requires that Executive agencies make every reasonable 
effort to ensure that the regulation (1) clearly specifies the 
preemptive effect, if any; (2) clearly specifies any effect on existing 
Federal law or regulation; (3) provides a clear legal standard for 
affected conduct while promoting simplification and burden reduction; 
(4) specifies the retroactive effect, if any; (5) adequately defines 
key terms; and (6) addresses other important issues affecting clarity 
and general draftsmanship under any guidelines issued by the Attorney 
General. Section 3(c) of Executive Order 12988 requires Executive 
agencies to review regulations in light of applicable standards in 
sections 3(a) and 3(b) to determine whether they are met or it is 
unreasonable to meet one or more of them. DOE has completed the 
required review and determined that, to the extent permitted by law, 
this final rule meets the relevant standards of Executive Order 12988.

G. Review Under the Unfunded Mandates Reform Act of 1995

    Title II of the Unfunded Mandates Reform Act of 1995 (UMRA) 
requires each Federal agency to assess the effects of Federal 
regulatory actions on State, local, and Tribal governments and the 
private sector. Public Law 104-4, sec. 201 (codified at 2 U.S.C. 1531). 
For a regulatory action resulting in a rule that may cause the 
expenditure by State, local, and Tribal governments, in the aggregate, 
or by the private sector of $100 million or more in any one year 
(adjusted annually for inflation), section 202 of UMRA requires a 
Federal agency to publish a written statement that estimates the 
resulting costs, benefits, and other effects on the national economy. 
(2 U.S.C. 1532(a), (b)) The UMRA also requires a Federal agency to 
develop an effective process to permit timely input by elected officers 
of State, local, and Tribal governments on a proposed ``significant 
intergovernmental mandate,'' and requires an agency plan for giving 
notice and opportunity for timely input to potentially affected small 
governments before establishing any requirements that might 
significantly or uniquely affect small governments. On March 18, 1997, 
DOE published a statement of policy on its process for 
intergovernmental consultation under UMRA. 62 FR 12820; also available 
at https://energy.gov/gc/office-general-counsel. DOE examined this final 
rule according to UMRA and its statement of policy and determined that 
the rule contains neither an intergovernmental mandate, nor a mandate 
that may result in the expenditure of $100 million or more in any year, 
so these requirements do not apply.

H. Review Under the Treasury and General Government Appropriations Act, 
1999

    Section 654 of the Treasury and General Government Appropriations 
Act, 1999 (Pub. L. 105-277) requires Federal agencies to issue a Family 
Policymaking Assessment for any rule that may affect family well-being. 
This final rule will not have any impact on the autonomy or integrity 
of the family as an institution. Accordingly, DOE has concluded that it 
is not necessary to prepare a Family Policymaking Assessment.

I. Review Under Executive Order 12630

    DOE has determined, under Executive Order 12630, ``Governmental 
Actions and Interference with Constitutionally Protected Property 
Rights'' 53 FR 8859 (March 18, 1988), that this regulation will not 
result in any takings that might require compensation under the Fifth 
Amendment to the U.S. Constitution.

J. Review Under Treasury and General Government Appropriations Act, 
2001

    Section 515 of the Treasury and General Government Appropriations 
Act, 2001 (44 U.S.C. 3516 note) provides for agencies to review most 
disseminations of information to the public under guidelines 
established by each agency pursuant to general guidelines issued by 
OMB. OMB's guidelines were published at 67 FR 8452 (Feb. 22, 2002), and 
DOE's guidelines were published at 67 FR 62446 (Oct. 7, 2002). DOE has 
reviewed this final rule under the OMB and DOE guidelines and has 
concluded that it is consistent with applicable policies in those 
guidelines.

K. Review Under Executive Order 13211

    Executive Order 13211, ``Actions Concerning Regulations That 
Significantly Affect Energy Supply, Distribution, or Use,'' 66 FR 28355 
(May 22, 2001), requires Federal agencies to prepare and submit to OMB, 
a Statement of Energy Effects for any significant energy action. A 
``significant energy action'' is defined as any action by an agency 
that promulgated or is expected to lead to promulgation of a final 
rule, and that (1) is a significant regulatory action under Executive 
Order 12866, or any successor order; and (2) is likely to have a 
significant adverse effect on the supply, distribution, or use of 
energy; or (3) is designated by the Administrator of OIRA as a 
significant energy action. For any significant energy action, the 
agency must give a detailed statement of any adverse effects on energy 
supply, distribution, or use if the regulation is implemented, and of 
reasonable alternatives to the action and their expected benefits on 
energy supply, distribution, and use.
    This regulatory action is not a significant regulatory action under 
Executive Order 12866. Moreover, it does not have a significant adverse

[[Page 1099]]

effect on the supply, distribution, or use of energy, nor has it been 
designated as a significant energy action by the Administrator of OIRA. 
Therefore, it is not a significant energy action, and, accordingly, DOE 
has not prepared a Statement of Energy Effects.

L. Review Under Section 32 of the Federal Energy Administration Act of 
1974

    Under section 301 of the Department of Energy Organization Act 
(Pub. L. 95-91; 42 U.S.C. 7101), DOE must comply with section 32 of the 
Federal Energy Administration Act of 1974, as amended by the Federal 
Energy Administration Authorization Act of 1977. (15 U.S.C. 788; FEAA) 
Section 32 essentially provides in relevant part that, where a proposed 
rule authorizes or requires use of commercial standards, the NOPR must 
inform the public of the use and background of such standards. In 
addition, section 32(c) requires DOE to consult with the Attorney 
General and the Chairman of the Federal Trade Commission (FTC) 
concerning the impact of the commercial or industry standards on 
competition.
    The test procedures for compressors adopted in this final rule 
incorporate testing methods contained in certain sections of the 
following commercial standards: ISO 1217:2009(E), as amended through 
ISO 1217:2009(E)/Amd.1:2016.
    While this test procedure is not exclusively based on this industry 
testing standard, some components of the DOE test procedure adopt 
definitions, test parameters, measurement techniques, and additional 
calculations from them without amendment. DOE has evaluated these 
standards and is unable to conclude whether it fully complies with the 
requirements of section 32(b) of the FEAA (i.e., whether it was 
developed in a manner that fully provides for public participation, 
comment, and review.) DOE has consulted with both the Attorney General 
and the Chairman of the FTC about the impact on competition of using 
the methods contained in these standards and has received no comments 
objecting to their use.

M. Congressional Notification

    As required by 5 U.S.C. 801, DOE will report to Congress on the 
promulgation of this rule before its effective date. The report will 
state that it has been determined that the rule is not a ``major rule'' 
as defined by 5 U.S.C. 804(2).

N. Description of Materials Incorporated by Reference

    In this final rule, DOE incorporates by reference specific sections 
from a method of test published by the International Organization for 
Standardization (ISO), titled ``Displacement compressors--Acceptance 
tests,'' ISO 1217:2009(E). Specifically, the test procedure codified by 
this final rule references the following parts of ISO 1217:2009(E): 
Sections 2, 3, and 4; sections 5.2, 5.3, 5.4, 5.6, 5.9; paragraphs 
6.2(g), and 6.2(h) including Table 1; sections C.1.1, C.2.2, C.2.3, 
C.2.4, C.4.1, C.4.2.1, C.4.2.3, C.4.3.2, C.4.4 of Annex C. The test 
procedure also references Amendment 1 to ISO 1217:2009(E) (ISO 
1217:2009(E)/Amd.1:2016), titled ``Calculation of isentropic efficiency 
and relationship with specific energy.'' Specifically, the test 
procedure codified by this final rule references the following parts of 
Amendment 1 to ISO 1217:2009(E): Sections 3.5.1 and 3.6.1; sections H.2 
and H.3 of Annex H.
    Members of the compressors industry developed ISO 1217:2009(E), 
which contains methods for determining inlet and discharge pressures, 
actual volume flow rate, packaged compressor power input, and package 
isentropic efficiency for electrically driven packaged displacement 
compressors.
    Copies of ISO 1217:2009(E) and of ISO 1217:2009(E)/Amd.1:2016 may 
be purchased from ISO at Chemin de Blandonnet 8, CP 401, 1214 Vernier, 
Geneva, Switzerland +41 22 749 01 11, or by going to www.iso.org.

V. Approval of the Office of the Secretary

    The Secretary of Energy has approved publication of this final 
rule.

List of Subjects

10 CFR part 429

    Administrative practice and procedure, Confidential business 
information, Energy conservation, Imports, Intergovernmental relations, 
Small businesses.

10 CFR part 431

    Administrative practice and procedure, Confidential business 
information, Energy conservation, Imports, Incorporation by reference, 
Intergovernmental relations, Small businesses.

    Issued in Washington, DC, on December 1, 2016.
Kathleen B. Hogan,
Deputy Assistant Secretary for Energy Efficiency, Energy Efficiency and 
Renewable Energy.

    For the reasons stated in the preamble, DOE proposes to amend parts 
429 and 431 of chapter II, subchapter D of title 10, Code of Federal 
Regulations as set forth below:

PART 429--CERTIFICATION, COMPLIANCE, AND ENFORCEMENT FOR CONSUMER 
PRODUCTS AND COMMERCIAL AND INDUSTRIAL EQUIPMENT

0
1. The authority citation for part 429 continues to read as follows:

    Authority: 42 U.S.C. 6291-6317; 28 U.S.C. 2461 note.

0
2. In Sec.  429.2, revise paragraph (a) to read as follows:


Sec.  429.2  Definitions.

    (a) The definitions found in Sec. Sec.  430.2, 431.2, 431.62, 
431.72, 431.82, 431.92, 431.102, 431.132, 431.152, 431.192, 431.202, 
431.222, 431.242, 431.262, 431.282, 431.292, 431.302, 431.322, 431.342, 
431.442, and 431.462 of this chapter apply for purposes of this part.
* * * * *

0
3. Add Sec.  429.63 to read as follows:


Sec.  429.63   Compressors.

    (a) Determination of represented value. Manufacturers must 
determine the represented value, which includes the certified rating, 
for each basic model of compressor either by testing in conjunction 
with the applicable sampling provisions or by applying an AEDM.
    (1) Units to be tested. (i) If the represented value is determined 
through testing, the general requirements of Sec.  429.11 apply; and
    (ii) For each basic model selected for testing, a sample of 
sufficient size must be randomly selected and tested to ensure that--
    (A) Measures of energy efficiency. Any represented value of the 
full- or part-load package isentropic efficiency or other measure of 
energy efficiency of a basic model for which customers would favor 
higher values is less than or equal to the lower of:
    (1) The mean of the sample, where:
    [GRAPHIC] [TIFF OMITTED] TR04JA17.007
    
    And x is the sample mean; n is the number of samples; and 
xi is the measured value for the ith sample; or,

[[Page 1100]]

    (2) The lower 95 percent confidence limit (LCL) of the true mean 
divided by 0.95, where:
[GRAPHIC] [TIFF OMITTED] TR04JA17.008

    And x is the sample mean; s is the sample standard deviation; n is 
the number of samples; and t0.95 is the t statistic for a 95 
percent one-tailed confidence interval with n-1 degrees of freedom 
(from appendix A of this subpart); and
    (B) Package specific power. The representative value(s) of package 
specific power of a basic model must be the mean of the package 
specific power measurement(s) for each tested unit of the basic model.
    (2) Alternative efficiency determination methods. In lieu of 
testing, any represented value of efficiency, consumption, or other 
non-energy metrics listed in paragraph (a)(3) of this section for a 
basic model may be determined through the application of an AEDM 
pursuant to the requirements of Sec.  429.70 and the provisions of this 
section, where:
    (i) Any represented values of package isentropic efficiency or 
other measure of energy consumption of a basic model for which 
customers would favor higher values must be less than or equal to the 
output of the AEDM; and
    (ii) Any represented values of package specific power, pressure 
ratio at full-load operating pressure, full-load actual volume flow 
rate, or full-load operating pressure must be the output of the AEDM 
corresponding to the represented value of package isentropic efficiency 
determined in paragraph (a)(2)(i) of this section.
    (3) Representations of non-energy metrics--(i) Full-load actual 
volume flow rate. The representative value of full-load actual volume 
flow rate of a basic model must be either--
    (A) The mean of the full-load actual volume flow rate for the units 
in the sample; or
    (B) As determined through the application of an AEDM pursuant to 
the requirements of Sec.  429.70.
    (ii) Full-load operating pressure. The representative value of 
full-load operating pressure of a basic model must be less than or 
equal to the maximum full-flow operating pressure and greater than or 
equal to the lesser of--
    (A) 90 percent of the maximum full-flow operating pressure; or
    (B) 10 psig less than the maximum full-flow operating pressure, 
where the maximum full-flow operating pressure must either be 
determined as the mean of the maximum full-flow operating pressure 
values for the units in the sample or through the application of an 
AEDM pursuant to the requirements of Sec.  429.70.
    (iii) Pressure ratio at full-load operating pressure. The 
representative value of pressure ratio at full-load operating pressure 
of a basic model must be either be determined as the mean of the 
pressure ratio at full-load operating pressure for the units in the 
sample or through the application of an AEDM pursuant to the 
requirements of Sec.  429.70.
    (b) [Reserved]


0
4. Section 429.70 is amended by adding paragraph (h) to read as 
follows:


Sec.  429.70   Alternative methods for determining energy efficiency 
and energy use.

* * * * *
    (h) Alternative efficiency determination method (AEDM) for 
compressors--(1) Criteria an AEDM must satisfy. A manufacturer may not 
apply an AEDM to a basic model to determine its efficiency pursuant to 
this section, unless:
    (i) The AEDM is derived from a mathematical model that estimates 
the energy efficiency or energy consumption characteristics of the 
basic model as measured by the applicable DOE test procedure;
    (ii) The AEDM is based on engineering or statistical analysis, 
computer simulation or modeling, or other analytic evaluation of 
performance data; and
    (iii) The manufacturer has validated the AEDM, in accordance with 
paragraph (h)(2) of this section.
    (2) Validation of an AEDM. Before using an AEDM, the manufacturer 
must validate the AEDM's accuracy and reliability as follows:
    (i) AEDM overview. The manufacturer must select at least the 
minimum number of basic models for each validation class specified in 
paragraph (h)(2)(iv) of this section to which the particular AEDM 
applies. Using the AEDM, calculate the energy use or energy efficiency 
for each of the selected basic models. Test each basic model and 
determine the represented value(s) in accordance with Sec.  429.63(a). 
Compare the results from the testing and the AEDM output according to 
paragraph (h)(2)(ii) of this section. The manufacturer is responsible 
for ensuring the accuracy and repeatability of the AEDM.
    (ii) AEDM basic model tolerances. (A) The predicted representative 
values for each basic model calculated by applying the AEDM may not be 
more than five percent greater (for measures of efficiency) or less 
(for measures of consumption) than the represented values determined 
from the corresponding test of the model.
    (B) The predicted package isentropic efficiency for each basic 
model calculated by applying the AEDM must meet or exceed the 
applicable federal energy conservation standard.
    (iii) Additional test unit requirements. (A) Each AEDM must be 
supported by test data obtained from physical tests of current models; 
and
    (B) Test results used to validate the AEDM must meet or exceed 
current, applicable Federal standards as specified in part 431 of this 
chapter; and
    (C) Each test must have been performed in accordance with the 
applicable DOE test procedure with which compliance is required at the 
time the basic models used for validation are distributed in commerce.
    (iv) Compressor validation classes.

------------------------------------------------------------------------
                                            Minimum number of distinct
            Validation class                basic models that must be
                                                      tested
------------------------------------------------------------------------
Rotary, Fixed-speed....................  2 Basic Models.
Rotary, Variable-speed.................  2 Basic Models.
------------------------------------------------------------------------

    (3) AEDM Records Retention Requirements. If a manufacturer has used 
an AEDM to determine representative values pursuant to this section, 
the manufacturer must have available upon request for inspection by the 
Department records showing:
    (i) The AEDM, including the mathematical model, the engineering or 
statistical analysis, and/or computer simulation or modeling that is 
the basis of the AEDM;
    (ii) Equipment information, complete test data, AEDM calculations, 
and the statistical comparisons from the units tested that were used to 
validate the AEDM pursuant to paragraph (h)(2) of this section; and
    (iii) Equipment information and AEDM calculations for each basic 
model to which the AEDM was applied.
    (4) Additional AEDM requirements. If requested by the Department, 
the manufacturer must:
    (i) Conduct simulations before representatives of the Department to 
predict the performance of particular basic models of the equipment to 
which the AEDM was applied;
    (ii) Provide analyses of previous simulations conducted by the 
manufacturer; and/or
    (iii) Conduct certification testing of basic models selected by the 
Department.


[[Page 1101]]



0
5. Section 429.134 is amended by adding paragraph (p) to read as 
follows:


Sec.  429.134   Product-specific enforcement provisions.

* * * * *
    (p) Compressors--(1) Verification of full-load operating pressure. 
(i) The maximum full-flow operating pressure of each tested unit of the 
basic model will be measured pursuant to the test requirements of 
appendix A to subpart T of part 431 of this chapter, where 90 percent 
of the value of full-load operating pressure certified by the 
manufacturer will be the starting point of the test method prior to 
increasing discharge pressure. The measured maximum full-flow operating 
pressure (either the single measured value for a single unit sample or 
the mean of the measured maximum full-flow operating pressures for a 
multiple unit sample) will be compared to the certified rating for 
full-load operating pressure to determine if the certified rating is 
valid or not. The certified rating for full-load operating pressure 
will be considered valid only if the certified rating for full-load 
operating pressure is less than or equal to the measured maximum full-
flow operating pressure and greater than or equal to the lesser of--
    (A) 90 percent of the measured maximum full-flow operating 
pressure; or
    (B) 10 psig less than the measured maximum full-flow operating 
pressure.
    (ii) If the certified full-load operating pressure is found to be 
valid, then the certified value will be used as the full-load operating 
pressure and will be the basis for determination of full-load actual 
volume flow rate, pressure ratio at full-load operating pressure, 
specific power, and package isentropic efficiency.
    (iii) If the certified full-load operating pressure is found to be 
invalid, then the measured maximum full-flow operating pressure will be 
used as the full-load operating pressure and will be the basis for 
determination of full-load actual volume flow rate, pressure ratio at 
full-load operating pressure, specific power, and package isentropic 
efficiency.
    (2) Verification of full-load actual volume flow rate. The measured 
full-load actual volume flow rate will be measured, pursuant to the 
test requirements of appendix A to subpart T of part 431 of this 
chapter, at the full-load operating pressure determined in paragraph 
(p)(1) of this section. The certified full-load actual volume flow rate 
will be considered valid only if the measurement(s) (either the 
measured full-load actual volume flow rate for a single unit sample or 
the mean of the measured values for a multiple unit sample) are within 
the percentage of the certified full-load actual volume flow rate 
specified in Table 1 of this section:

   Table 1 of Sec.   429.134--Allowable Percentage Deviation From the
               Certified Full-Load Actual Volume Flow Rate
------------------------------------------------------------------------
                                                             Allowable
                                                          percent of the
Manufacturer certified full-load actual volume flow rate     certified
                      (m3/s) x 10-3                          full-load
                                                           actual volume
                                                          flow rate  (%)
------------------------------------------------------------------------
0 < and <= 8.3..........................................   7
8.3 < and <= 25.........................................   6
25 < and <= 250.........................................   5
> 250...................................................   4
------------------------------------------------------------------------

    (i) If the certified value of full-load actual volume flow rate is 
found to be valid, the full-load actual volume flow rate certified by 
the manufacturer will be used as the basis for determination of the 
applicable standard.
    (ii) If the certified value of full-load actual volume flow rate is 
found to be invalid, the entire sample (one or multiple units) will be 
considered as failing the enforcement test.
    (3) Ancillary equipment. Prior to testing each compressor, DOE will 
install any required ancillary equipment specified by the manufacturer 
in the certification report submitted pursuant to Sec.  429.63(b).

PART 431--ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL AND 
INDUSTRIAL EQUIPMENT

0
6. The authority citation for part 431 continues to read as follows:

    Authority: 42 U.S.C. 6291-6317; 28 U.S.C. 2461 note.


0
7. Section 431.342 is revised to read as follows:


Sec.  431.342   Definitions concerning compressors.

    The following definitions are applicable to this subpart, including 
appendix A. In cases where there is a conflict, the language of the 
definitions adopted in this section take precedence over any 
descriptions or definitions found in any other source, including in ISO 
Standard 1217:2009(E), ``Displacement compressors--Acceptance tests,'' 
as amended through Amendment 1:2016(E), ``Calculation of isentropic 
efficiency and relationship with specific energy'' (incorporated by 
reference, see Sec.  431.343). In cases where definitions reference 
design intent, DOE will consider all relevant information, including 
marketing materials, labels and certifications, and equipment design, 
to determine design intent.
    Actual volume flow rate means the volume flow rate of air, 
compressed and delivered at the standard discharge point, referred to 
conditions of total temperature, total pressure and composition 
prevailing at the standard inlet point, and as determined in accordance 
with the test procedures prescribed in Sec.  431.344.
    Air compressor means a compressor designed to compress air that has 
an inlet open to the atmosphere or other source of air, and is made up 
of a compression element (bare compressor), driver(s), mechanical 
equipment to drive the compressor element, and any ancillary equipment.
    Ancillary equipment means any equipment distributed in commerce 
with an air compressor but that is not a bare compressor, driver, or 
mechanical equipment. Ancillary equipment is considered to be part of a 
given air compressor, regardless of whether the ancillary equipment is 
physically attached to the bare compressor, driver, or mechanical 
equipment at the time when the air compressor is distributed in 
commerce.
    Auxiliary substance means any substance deliberately introduced 
into a compression process to aid in compression of a gas by any of the 
following: Lubricating, sealing mechanical clearances, or absorbing 
heat.
    Bare compressor means the compression element and auxiliary devices 
(e.g., inlet and outlet valves, seals, lubrication system, and gas flow 
paths) required for performing the gas compression process, but does 
not include any of the following:
    (1) The driver;
    (2) Speed-adjusting gear(s);
    (3) Gas processing apparatuses and piping; and
    (4) Compressor equipment packaging and mounting facilities and 
enclosures.
    Basic model means all units of a class of compressors manufactured 
by one manufacturer, having the same primary energy source, the same 
compressor motor nominal horsepower, and essentially identical 
electrical, physical, and functional (or pneumatic) characteristics 
that affect energy consumption and energy efficiency.
    Brushless electric motor means a machine that converts electrical 
power into rotational mechanical power without use of sliding 
electrical contacts.
    Compressor means a machine or apparatus that converts different 
types

[[Page 1102]]

of energy into the potential energy of gas pressure for displacement 
and compression of gaseous media to any higher pressure values above 
atmospheric pressure and has a pressure ratio at full-load operating 
pressure greater than 1.3.
    Compressor motor nominal horsepower means the motor horsepower of 
the electric motor, as determined in accordance with the applicable 
procedures in subparts B and X of this part, with which the rated air 
compressor is distributed in commerce.
    Driver means the machine providing mechanical input to drive a bare 
compressor directly or through the use of mechanical equipment.
    Fixed-speed compressor means an air compressor that is not capable 
of adjusting the speed of the driver continuously over the driver 
operating speed range in response to incremental changes in the 
required compressor flow rate.
    Full-load actual volume flow rate means the actual volume flow rate 
of the compressor at the full-load operating pressure.
    Lubricant-free compressor means a compressor that does not 
introduce any auxiliary substance into the compression chamber at any 
time during operation.
    Lubricated compressor means a compressor that introduces an 
auxiliary substance into the compression chamber during compression.
    Maximum full-flow operating pressure means the maximum discharge 
pressure at which the compressor is capable of operating, as determined 
in accordance with the test procedure prescribed in Sec.  431.344.
    Mechanical equipment means any component of an air compressor that 
transfers energy from the driver to the bare compressor.
    Package isentropic efficiency means the ratio of power required for 
an ideal isentropic compression process to the actual packaged 
compressor power input used at a given load point, as determined in 
accordance with the test procedures prescribed in Sec.  431.344.
    Package specific power means the compressor power input at a given 
load point, divided by the actual volume flow rate at the same load 
point, as determined in accordance with the test procedures prescribed 
in Sec.  431.344.
    Positive displacement compressor means a compressor in which the 
admission and diminution of successive volumes of the gaseous medium 
are performed periodically by forced expansion and diminution of a 
closed space(s) in a working chamber(s) by means of displacement of a 
moving member(s) or by displacement and forced discharge of the gaseous 
medium into the high-pressure area.
    Pressure ratio at full-load operating pressure means the ratio of 
discharge pressure to inlet pressure, determined at full-load operating 
pressure in accordance with the test procedures prescribed in Sec.  
431.344.
    Reciprocating compressor means a positive displacement compressor 
in which gas admission and diminution of its successive volumes are 
performed cyclically by straight-line alternating movements of a moving 
member(s) in a compression chamber(s).
    Rotary compressor means a positive displacement compressor in which 
gas admission and diminution of its successive volumes or its forced 
discharge are performed cyclically by rotation of one or several rotors 
in a compressor casing.
    Rotor means a compression element that rotates continually in a 
single direction about a single shaft or axis.
    Variable-speed compressor means an air compressor that is capable 
of adjusting the speed of the driver continuously over the driver 
operating speed range in response to incremental changes in the 
required compressor actual volume flow rate.

0
8. Add Sec. Sec.  431.343 through 431.346 and appendix A to subpart T 
to read as follows:

Sec.
431.343 Materials incorporated by reference.
431.344 Test procedure for measuring and determining energy 
efficiency of compressors.
431.345 [Reserved]
431.346 [Reserved]

Appendix A to Subpart T of Part 431--Uniform Test Method for Certain 
Air Compressors


Sec.  431.343   Materials incorporated by reference.

    (a) General. DOE incorporates by reference the following standards 
into part 431. The material listed has been approved for incorporation 
by reference by the Director of the Federal Register in accordance with 
6 U.S.C. 522(a) and 1 CFR part 51. Any subsequent amendment to a 
standard by the standard-setting organization will not affect the DOE 
test procedures unless and until amended by DOE. Material is 
incorporated as it exists on the date of the approval and a notice of 
any change in the material will be published in the Federal Register. 
All approved material is available from the sources below. It is 
available for inspection at U.S. Department of Energy, Office of Energy 
Efficiency and Renewable Energy, Building Technologies Program, Sixth 
Floor, 950 L'Enfant Plaza SW., Washington, DC 20024, (202) 586-6636, or 
go to https://www1.eere.energy.gov/buildings/appliance_standards/. Also, 
this material is available for inspection at the National Archives and 
Records Administration (NARA). For information on the availability of 
this material at NARA, call 202-741-6030, or go to: https://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.
    (b) ISO. International Organization for Standardization, Chemin de 
Blandonnet 8, CP 401, 1214 Vernier, Geneva, Switzerland +41 22 749 01 
11, www.iso.org.
    (1) ISO Standard 1217:2009(E), (``ISO 1217:2009(E)''), 
``Displacement compressors--Acceptance tests,'' July 1, 2009, IBR 
approved for appendix A to this subpart:
    (i) Section 2. Normative references;
    (ii) Section 3. Terms and definitions;
    (iii) Section 4. Symbols;
    (iv) Section 5. Measuring equipment, methods and accuracy 
(excluding 5.1, 5.5, 5.7, and 5.8);
    (v) Section 6. Test procedures, introductory text to Section 6.2, 
Test arrangements, and paragraphs 6.2(g) and 6.2(h) including Table 1--
Maximum deviations from specified values and fluctuations from average 
readings;
    (vi) Annex C (normative), Simplified acceptance test for 
electrically driven packaged displacement compressors (excluding C.1.2, 
C.2.1, C.3, C.4.2.2, C.4.3.1, and C.4.5).
    (2) ISO 1217:2009/Amd.1:2016(E), Displacement compressors--
Acceptance tests (Fourth edition); Amendment 1: ``Calculation of 
isentropic efficiency and relationship with specific energy,'' April 
15, 2016, IBR approved for appendix A to this subpart:
    (i) Section 3.5.1: isentropic power;
    (ii) Section 3.6.1: isentropic efficiency;
    (iii) Annex H (informative), Isentropic efficiency and its relation 
to specific energy requirement, sections H.2, Symbols and subscripts, 
and H.3, Derivation of isentropic power.


Sec.  431.344   Test procedure for measuring and determining energy 
efficiency of compressors.

    (a) Scope. This section is a test procedure that is applicable to a 
compressor that meets the following criteria:
    (1) Is an air compressor;
    (2) Is a rotary compressor;
    (3) Is not a liquid ring compressor;
    (4) Is driven by a brushless electric motor;
    (5) Is a lubricated compressor;

[[Page 1103]]

    (6) Has a full-load operating pressure greater than or equal to 75 
pounds per square inch gauge (psig) and less than or equal to 200 psig;
    (7) Is not designed and tested to the requirements of the American 
Petroleum Institute Standard 619, ``Rotary-Type Positive-Displacement 
Compressors for Petroleum, Petrochemical, and Natural Gas Industries;''
    (8) Has full-load actual volume flow rate greater than or equal to 
35 cubic feet per minute (cfm), or is distributed in commerce with a 
compressor motor nominal horsepower greater than or equal to 10 
horsepower (hp); and
    (9) Has a full-load actual volume flow rate less than or equal to 
1,250 cfm, or is distributed in commerce with a compressor motor 
nominal horsepower less than or equal to 200 hp.
    (b) Testing and calculations. Determine the applicable full-load 
package isentropic efficiency ([eta]isen,FL), part-load 
package isentropic efficiency ([eta]isen,PL), package 
specific power, maximum full-flow operating pressure, full-load 
operating pressure, full-load actual volume flow rate, and pressure 
ratio at full-load operating pressure using the test procedure set 
forth in appendix A of this subpart.


Sec.  431.345   [Reserved]


Sec.  431.346   [Reserved]

Appendix A to Subpart T of Part 431--Uniform Test Method for Certain 
Air Compressors

    Note: Starting on July 3, 2017, any representations made with 
respect to the energy use or efficiency of compressors subject to 
testing pursuant to 10 CFR 431.344 must be made in accordance with 
the results of testing pursuant to this appendix.

I. Measurements, Test Conditions, and Equipment Configuration

A. Measurement Equipment

    A.1. For the purposes of measuring air compressor performance, 
the equipment necessary to measure volume flow rate, inlet and 
discharge pressure, temperature, condensate, and packaged compressor 
power input must comply with the equipment and accuracy requirements 
specified in ISO 1217:2009(E) sections 5.2, 5.3, 5.4, 5.6, 5.9, and 
Annex C, sections C.2.3 and C.2.4 (incorporated by reference, see 
Sec.  431.343).
    A.2. Electrical measurement equipment must be capable of 
measuring true root mean square (RMS) current, true RMS voltage, and 
real power up to the 40th harmonic of fundamental supply source 
frequency.
    A.3. Any instruments used to measure a particular parameter 
specified in paragraph (A.1.) must have a combined accuracy of 
2.0 percent of the measured value at the fundamental 
supply source frequency, where combined accuracy is the square root 
of the sum of the squares of individual instrument accuracies.
    A.4. Any instruments used to directly measure the density of air 
must have an accuracy of 1.0 percent of the measured 
value.
    A.5. Any pressure measurement equipment used in a calculation of 
another variable (e.g., actual volume flow rate) must also meet all 
accuracy and measurement requirements of section 5.2 of ISO 
1217:2009(E) (incorporated by reference, see Sec.  431.343).
    A.6. Any temperature measurement equipment used in a calculation 
of another variable (e.g., actual volume flow rate) must also meet 
all accuracy and measurement requirements of section 5.3 of ISO 
1217:2009(E) (incorporated by reference, see Sec.  431.343).
    A.7. Where ISO 1217:2009(E) refers to ``corrected volume flow 
rate,'' the term is deemed synonymous with the term ``actual volume 
flow rate,'' as defined in section 3.4.1 of ISO 1217:2009(E) 
(incorporated by reference, see Sec.  431.343).

B. Test Conditions and Configuration of Unit Under Test

    B.1. For both fixed-speed and variable-speed compressors, 
conduct testing in accordance with the test conditions, unit 
configuration, and specifications of ISO 1217:2009(E), Section 6.2 
paragraphs (g) and (h) and Annex C, sections C.1.1, C.2.2, C.2.3, 
C.2.4, C.4.1, C.4.2.1, C.4.2.3, and C.4.3.2 (incorporated by 
reference, see Sec.  431.343).
    B.2. The power supply must:
    (1) Maintain the voltage greater than or equal to 95 percent and 
less than or equal to 110 percent of the rated value of the motor,
    (2) Maintain the frequency within 5 percent of the 
rated value of the motor,
    (3) Maintain the voltage unbalance of the power supply within 
3 percent of the rated values of the motor, and
    (4) Maintain total harmonic distortion below 12 percent 
throughout the test.
    B.3. Ambient Conditions. The ambient air temperature must be 
greater than or equal to 68 [deg]F and less than or equal to 90 
[deg]F for the duration of testing. There are no ambient condition 
requirements for inlet pressure or relative humidity.
    B.4. All equipment indicated in Table 1 of this appendix must be 
present and installed for all tests specified in this appendix. If 
the compressor is distributed in commerce without an item from Table 
1 of this appendix, the manufacturer must provide an appropriate 
item to be installed for the test. Additional ancillary equipment 
may be installed for the test, if distributed in commerce with the 
compressor, but this additional ancillary equipment is not required. 
If any of the equipment listed in Table 2 of this appendix is 
distributed in commerce with units of the compressor basic model, it 
must be present and installed for all tests specified in this 
appendix.

                                     Table 1--Equipment Required During Test
----------------------------------------------------------------------------------------------------------------
                                               Fixed-speed  rotary  air           Variable-speed  rotary  air
                Equipment                             compressors                         compressors
----------------------------------------------------------------------------------------------------------------
Driver..................................  Yes...............................  Yes.
Bare compressors........................  Yes...............................  Yes.
Inlet filter............................  Yes...............................  Yes.
Inlet valve.............................  Yes...............................  Yes.
Minimum pressure check valve/backflow     Yes...............................  Yes.
 check valve.
Lubricant separator.....................  Yes...............................  Yes.
Air piping..............................  Yes...............................  Yes.
Lubricant piping........................  Yes...............................  Yes.
Lubricant filter........................  Yes...............................  Yes.
Lubricant cooler........................  Yes...............................  Yes.
Thermostatic valve......................  Yes...............................  Yes.
Electrical switchgear or frequency        Yes...............................  Not applicable.\1\
 converter for the driver.
Device to control the speed of the        Not applicable \2\................  Yes.
 driver (e.g., variable speed drive).
Compressed air cooler(s)................  Yes...............................  Yes.
Pressure switch, pressure transducer, or  Yes...............................  Yes.
 similar pressure control device.
Moisture separator and drain............  Yes...............................  Yes.
----------------------------------------------------------------------------------------------------------------
\1\ This category is not applicable to variable-speed rotary air compressors.
\2\ This category is not applicable to fixed-speed rotary air compressors.


[[Page 1104]]


            Table 2--Equipment Required During Test, if Distributed in Commerce With the Basic Model
----------------------------------------------------------------------------------------------------------------
                                                                                  Variable-speed  rotary air
                Equipment                 Fixed-speed rotary air compressors              compressors
----------------------------------------------------------------------------------------------------------------
Cooling fan(s) and motors...............  Yes...............................  Yes.
Mechanical equipment....................  Yes...............................  Yes.
Lubricant pump..........................  Yes...............................  Yes.
Interstage cooler.......................  Yes...............................  Yes.
Electronic or electrical controls and     Yes...............................  Yes.
 user interface.
All protective and safety devices.......  Yes...............................  Yes.
----------------------------------------------------------------------------------------------------------------

    B.5. The inlet of the compressor under test must be open to the 
atmosphere and take in ambient air for all tests specified in this 
appendix.
    B.6. The compressor under test must be set up according to all 
manufacturer instructions for normal operation (e.g., verify 
lubricant level, connect all loose electrical connections, close off 
bottom of unit to floor, cover forklift holes).
    B.7. The piping connected to the discharge orifice of the 
compressor must be of a diameter at least equal to that of the 
compressor discharge orifice to which it is connected. The piping 
must be straight with a length of at least 6 inches.
    B.8. Transducers used to record compressor discharge pressure 
must be located on the discharge piping between 2 inches and 6 
inches, inclusive, from the discharge orifice of the compressor. The 
pressure tap for transducers must be located at the highest point of 
the pipe's cross section.

II. Determination of Package Isentropic Efficiency, Package Specific 
Power, and Pressure Ratio at Full-Load Operating Pressure

A. Data Collection and Analysis

    A.1. Stabilization. Record data at each load point under steady-
state conditions. Steady-state conditions are achieved when a set of 
two consecutive readings taken at least 10 seconds apart and no more 
than 60 seconds apart are within the maximum permissible fluctuation 
from the average (of the two consecutive readings), as specified in 
Table 1 of ISO 1217:2009(E) (incorporated by reference, see Sec.  
431.343) for--
    (1) Discharge pressure;
    (2) Temperature at the nozzle or orifice plate, measured per 
section 5.3 of ISO 1217:2009(E) (incorporated by reference, see 
Sec.  431.343); and
    (3) Differential pressure over the nozzle or orifice plate, 
measured per section 5.2 of ISO 1217:2009(E) (incorporated by 
reference, see Sec.  431.343).
    A.2. Data Sampling and Frequency. At each load point, record a 
minimum set of 16 unique readings, collected over a minimum time of 
15 minutes. Each consecutive reading must be no more than 60 seconds 
apart, and not less than 10 seconds apart. All readings at each load 
point must be within the maximum permissible fluctuation from 
average specified in Table 1 of ISO 1217:2009(E) (incorporated by 
reference, see Sec.  431.343) for--
    (1) Discharge pressure;
    (2) Temperature at the nozzle or orifice plate, measured per 
section 5.3 of ISO 1217:2009(E) (incorporated by reference, see 
Sec.  431.343); and
    (3) Differential pressure over the nozzle or orifice plate, 
measured per section 5.2 of ISO 1217:2009(E) (incorporated by 
reference, see Sec.  431.343).
    If one or more readings do not meet the requirements, then all 
previous readings must be disregarded and a new set of at least 16 
new unique readings must be collected over a minimum time of 15 
minutes. Average the readings to determine the value of each 
parameter to be used in subsequent calculations.
    A.3. Calculations and Rounding. Perform all calculations using 
raw measured values. Round the final result for package isentropic 
efficiency to the thousandth (i.e., 0.001), for package specific 
power in kilowatts per 100 cubic feet per minute to the nearest 
hundredth (i.e., 0.01), for pressure ratio at full-load operating 
pressure to the nearest tenth (i.e., 0.1), for full-load actual 
volume flow rate in cubic feet per minute to the nearest tenth 
(i.e., 0.1), and for full-load operating pressure in pounds per 
square inch gauge (psig) to the nearest integer (i.e., 1). All terms 
and quantities refer to values determined in accordance with the 
procedures set forth in this appendix for the tested unit.

B. Full-Load Operating Pressure and Full-Load Actual Volume Flow 
Rate

    Determine the full-load operating pressure and full-load actual 
volume flow rate (referenced throughout this appendix) in accordance 
with the procedures prescribed in section III of this appendix.

C. Full-Load Package Isentropic Efficiency for Fixed- and Variable-
Speed Air Compressors

    Use this test method to test fixed-speed air compressors and 
variable-speed air compressors.
    C.1. Test unit at full-load operating pressure and full-load 
volume flow rate according to the requirements established in 
sections I, II.A, and II.B of this appendix. Measure volume flow 
rate and calculate actual volume flow rate in accordance with 
section C.4.2.1 of Annex C of ISO 1217:2009(E) (incorporated by 
reference, see Sec.  431.343) with no corrections made for shaft 
speed. Measure discharge gauge pressure and packaged compressor 
power input. Measured discharge gauge pressure and calculated actual 
volume flow rate must be within the deviation limits for discharge 
pressure and volume flow rate specified in Tables C.1 and C.2 of 
Annex C of ISO 1217:2009(E) (incorporated by reference, see Sec.  
431.343), where full-load operating pressure and full-load actual 
volume flow rate (as determined in section III of this appendix) are 
the targeted values.
    C.2. Calculate the package isentropic efficiency at full-load 
operating pressure and full-load actual volume flow rate (full-load 
package isentropic efficiency, [eta]isen,FL) using the 
equation for isentropic efficiency in section 3.6.1 of ISO 
1217:2009(E) as modified by ISO 1217:2009/Amd.1:2016(E) 
(incorporated by reference, see Sec.  431.343). For 
Pisen, use the isentropic power required for compression 
at full-load operating pressure and full-load actual volume flow 
rate, as determined in section II.C.2.1 of this appendix. For 
Preal, use the real packaged compressor power input at 
full-load operating pressure and full-load actual volume flow rate, 
as determined in section II.C.2.2 of this appendix.
    C.2.1. Calculate the isentropic power required for compression 
at full-load operating pressure and full-load actual volume flow 
rate using equation (H.6) of Annex H of ISO 1217:2009/Amd.1:2016(E) 
(incorporated by reference, see Sec.  431.343). For qV1, 
use the actual volume flow rate (cubic meters per second) calculated 
in section II.C.1 of this appendix. For p1, use 100 kPa. 
For p2, use the sum of (a) 100 kPa, and (b) the measured 
discharge gauge pressure (Pa) from section II.C.1 of this appendix. 
For K, use the isentropic exponent (ratio of specific heats) of air, 
which, for the purposes of this test procedure, is 1.400.
    C.2.2. Calculate real packaged compressor power input at full-
load operating pressure and full-load actual volume flow rate using 
the following equation:

Preal,100 = K5 [middot] 
PPR,100

Where:

K5 = correction factor for inlet pressure, as determined 
in section C.4.3.2 of Annex C to ISO 1217:2009(E) (incorporated by 
reference, see Sec.  431.343). For calculations of this variable use 
a value of 100 kPa for contractual inlet pressure; and
PPR,100 = packaged compressor power input reading 
at full-load operating pressure and full-load actual volume flow 
rate measured in section II.C.1 of this appendix (W).

D. Part-Load Package Isentropic Efficiency for Variable-Speed Air 
Compressors

    Use this test method to test variable-speed air compressors.

[[Page 1105]]

    D.1. Test unit at two load points: (1) Full-load operating 
pressure and 70 percent of full-load actual volume flow rate and (2) 
full-load operating pressure and 40 percent of full-load actual 
volume flow rate, according to the requirements established in 
sections I, II.A, and II.B of this appendix. To reach each specified 
load point, adjust the speed of the driver and the backpressure of 
the system. For each load point, measure volume flow rate and 
calculate actual volume flow rate in accordance with section C.4.2.1 
of Annex C of ISO 1217:2009(E) (incorporated by reference, see Sec.  
431.343), with no corrections made for shaft speed. For each load 
point, measure discharge gauge pressure and packaged compressor 
power input. Measured discharge gauge pressure and calculated actual 
volume flow rate must be within the deviation limits for discharge 
pressure and volume flow rate specified in Tables C.1 and C.2 of 
Annex C of ISO 1217:2009(E), where the targeted values are as 
specified in the beginning of this section.
    D.2. For variable-speed compressors, calculate the part-load 
package isentropic efficiency using the following equation:

[eta]isen,PL = [omega]40 x 
[eta]isen,40 + [omega]70 x 
[eta]isen,70 + [omega]100 x 
[eta]isen,100

Where:
[eta]isen,PL = part-load package isentropic efficiency 
for a variable-speed compressor;
[eta]isen,100 = package isentropic efficiency at 
full-load operating pressure and 100 percent of full-load actual 
volume flow rate, as determined in section II.C.2 of this appendix;
[eta]isen,70 = package isentropic efficiency at 
full-load operating pressure and 70 percent of full-load actual 
volume flow rate, as determined in section II.D.3 of this appendix;
[eta]isen,40 = package isentropic efficiency at 
full-load operating pressure and 40 percent of full-load actual 
volume flow rate, as determined in section II.D.4 of this appendix;
[omega]40 = weighting at 40 percent of full-load 
actual volume flow rate and is 0.25;
[omega]70 = weighting at 70 percent of full-load 
actual volume flow rate and is 0.50; and
[omega]100 = weighting at 100 percent of full-
load actual volume flow rate and is 0.25.
    D.3. Calculate package isentropic efficiency at full-load 
operating pressure and 70 percent of full-load actual volume flow 
rate using the equation for isentropic efficiency in section 3.6.1 
of ISO 1217:2009(E) as modified by ISO 1217:2009/Amd.1:2016(E) 
(incorporated by reference, see Sec.  431.343). For 
Pisen, use the isentropic power required for compression 
at full-load operating pressure and 70 percent of full-load actual 
volume flow rate, as determined in section II.D.3.1 of this 
appendix. For Preal, use the real packaged compressor 
power input at full-load operating pressure and 70 percent of full-
load actual volume flow rate, as determined in section II.D.3.2 of 
this appendix.
    D.3.1. Calculate the isentropic power required for compression 
at full-load operating pressure and 70 percent of full-load actual 
volume flow rate using equation (H.6) of Annex H of ISO 1217:2009/
Amd.1:2016(E) (incorporated by reference, see Sec.  431.343). For 
qV1, use actual volume flow rate (cubic meters per 
second) at full-load operating pressure and 70 percent of full-load 
actual volume flow rate, as calculated in section II.D.1 of this 
appendix. For p1, use 100 kPa. For p2, use the 
sum of (a) 100 kPa, and (b) discharge gauge pressure (Pa) at full-
load operating pressure and 70 percent of full-load actual volume 
flow rate, as calculated in section II.D.1 of this appendix. For K, 
use the isentropic exponent (ratio of specific heats) of air, which, 
for the purposes of this test procedure, is 1.400.
    D.3.2. Calculate real packaged compressor power input at full-
load operating pressure and 70 percent of full-load actual volume 
flow rate using the following equation:

Preal,70 = K5 [middot] 
PPR,70

Where:

K5 = correction factor for inlet pressure, as determined 
in section C.4.3.2 of Annex C to ISO 1217:2009(E) (incorporated by 
reference, see Sec.  431.343). For calculations of this variable use 
a value of 100 kPa for contractual inlet pressure; and

PPR,70 = packaged compressor power input reading 
at full-load operating pressure and 70 percent of full-load actual 
volume flow rate, as measured in section II.D.1 of this appendix 
(W).

    D.4. Calculate package isentropic efficiency at full-load 
operating pressure and 40 percent of full-load actual volume flow 
rate using the equation for isentropic efficiency in section 3.6.1 
of ISO 1217:2009(E) as modified by ISO 1217:2009/Amd.1:2016(E) 
(incorporated by reference, see Sec.  431.343). For 
Pisen, use the isentropic power required for compression 
at full-load operating pressure and 40 percent of full-load actual 
volume flow rate, as determined in section II.D.4.1 of this 
appendix. For Preal, use the real packaged compressor 
power input at full-load operating pressure and 40 percent of full-
load actual volume flow rate, as determined in section II.D.4.2 of 
this appendix.
    D.4.1. Calculate the isentropic power required for compression 
at full-load operating pressure and 40 percent of full-load actual 
volume flow rate using equation (H.6) of Annex H of ISO 1217:2009/
Amd.1:2016(E) (incorporated by reference, see Sec.  431.343). For 
qV1, use actual volume flow rate (cubic meters per 
second) at full-load operating pressure and 40 percent of full-load 
actual volume flow rate, as calculated in section II.D.1 of this 
appendix. For p1, use 100 kPa. For p2, use the 
sum of (a) 100 kPa, and (b) discharge gauge pressure (Pa) at full-
load operating pressure and 40 percent of full-load actual volume 
flow rate, as calculated in section II.D.1 of this appendix. For K, 
use the isentropic exponent (ratio of specific heats) of air, which, 
for the purposes of this test procedure, is 1.400.
    D.4.2. Calculate real packaged compressor power input at full-
load operating pressure and 40 percent of full-load actual volume 
flow rate using the following equation:

Preal,40 = K5 [middot] 
PPR,40%

Where:

K5 = correction factor for inlet pressure, as determined 
in section C.4.3.2 of Annex C to ISO 1217:2009(E) (incorporated by 
reference, see Sec.  431.343). For calculations of this variable use 
a value of 100 kPa for contractual inlet pressure; and
PPR,40 = packaged compressor power input reading 
at full-load operating pressure and 40 percent of full-load actual 
volume flow rate, as measured in section II.D.1 of this appendix 
(W).

E. Determination of Package Specific Power

    For both fixed and variable-speed air compressors, determine the 
package specific power, at any load point, using the equation for 
specific energy consumption in section C.4.4 of Annex C of ISO 
1217:2009(E) (incorporated by reference, see Sec.  431.343) and 
other values measured pursuant to this appendix, with no correction 
for shaft speed. Calculate PPcorr in section C.4.4 of 
Annex C of ISO 1217:2009(E) (incorporated by reference, see Sec.  
431.343) using the following equation:

PPcorr = K5 [middot] PPR

Where:

K5 = correction factor for inlet pressure, as determined 
in section C.4.3.2 of Annex C to ISO 1217:2009(E) (incorporated by 
reference, see Sec.  431.343). For calculations of this variable use 
a value of 100 kPa for contractual inlet pressure; and
PPR = packaged compressor power input reading (W), as determined in 
section C.2.4 of Annex C to ISO 1217:2009(E) (incorporated by 
reference, see Sec.  431.343).

F. Determination of Pressure Ratio at Full-Load Operating Pressure

    Pressure ratio at full-load operating pressure, as defined in 
Sec.  431.342, is calculated using the following equation:
[GRAPHIC] [TIFF OMITTED] TR04JA17.008

Where:

PR = pressure ratio at full-load operating pressure;
p1 = 100 kPa; and
pFL = full-load operating pressure, determined in section 
III.C.4 of this appendix (Pa gauge).

III. Method to Determine Maximum Full-Flow Operating Pressure, Full-
Load Operating Pressure, and Full-Load Actual Volume Flow Rate

A. Principal Strategy

    The principal strategy of this method is to incrementally 
increase discharge pressure by 2 psig relative to a starting point, 
and identify the maximum full-flow operating pressure at which the 
compressor is capable of operating. The maximum discharge pressure 
achieved is the maximum full-flow operating pressure. The full-load 
operating pressure and full-load actual volume flow rate are 
determined based on the maximum full-flow operating pressure.

[[Page 1106]]

B. Pre-test Instructions

B.1. Safety

    For the method presented in section III.C.1 of this appendix, 
only test discharge pressure within the safe operating range of the 
compressor, as specified by the manufacturer in the installation and 
operation manual shipped with the unit. Make no changes to safety 
limits or equipment. Do not violate any manufacturer-provided motor 
operational guidelines for normal use, including any restriction on 
instantaneous and continuous input power draw and output shaft power 
(e.g., electrical rating and service factor limits).

B.2. Adjustment of Discharge Pressure

    B.2.1. If the air compressor is not equipped, as distributed in 
commerce by the manufacturer, with any mechanism to adjust the 
maximum discharge pressure output limit, proceed to section III.B.3 
of this appendix.
    B.2.2. If the air compressor is equipped, as distributed in 
commerce by the manufacturer, with any mechanism to adjust the 
maximum discharge pressure output limit, then adjust this mechanism 
to the maximum pressure allowed, according to the manufacturer's 
operating instructions for these mechanisms. Mechanisms to adjust 
discharge pressure may include, but are not limited to, onboard 
digital or analog controls, and user-adjustable inlet valves.

B.3. Driver speed

    If the unit under test is a variable-speed compressor, maintain 
maximum driver speed throughout the test. If the unit under test is 
a fixed-speed compressor with a multi-speed driver, maintain driver 
speed at the maximum speed throughout the test.

B.4. Measurements and Tolerances

B.4.1. Recording

    Record data by electronic means such that the requirements of 
section B.4.5 of section III of this appendix are met.

B.4.2. Discharge Pressure

    Measure discharge pressure in accordance with section 5.2 of ISO 
1217:2009(E) (incorporated by reference, see Sec.  431.343). Express 
compressor discharge pressure in psig in reference to ambient 
conditions, and record it to the nearest integer. Specify targeted 
discharge pressure points in integer values only. The maximum 
allowable measured deviation from the targeted discharge pressure at 
each tested point is 1 psig.

B.4.3. Actual Volume Flow Rate

    Measure actual volume flow rate in accordance with section 
C.4.2.1 of Annex C of ISO 1217:2009(E) (incorporated by reference, 
see Sec.  431.343) (where it is called ``corrected volume flow 
rate'') with no corrections made for shaft speed. Express compressor 
actual volume flow rate in cubic feet per minute at inlet conditions 
(cfm).

B.4.4. Stabilization

    Record data at each tested load point under steady-state 
conditions, as determined in section II.A.1 of this appendix.

B.4.5. Data Sampling and Frequency

    At each load point, record a set of at least of two readings, 
collected at a minimum of 10 seconds apart. All readings at each 
load point must be within the maximum permissible fluctuation from 
the average (of the two consecutive readings), as specified in 
II.A.2 of this appendix. Average the measurements to determine the 
value of each parameter to be used in subsequent calculations.

B.5. Adjusting System Backpressure

    Set up the unit under test so that backpressure on the unit can 
be adjusted (e.g., by valves) incrementally, causing the measured 
discharge pressure to change, until the compressor is in an unloaded 
condition.

B.6. Unloaded Condition

    A unit is considered to be in an unloaded condition if capacity 
controls on the unit automatically reduce the actual volume flow 
rate from the compressor (e.g., shutting the motor off, or unloading 
by adjusting valves).

C. Test Instructions

    C.1. Adjust the backpressure of the system so the measured 
discharge pressure is 90 percent of the expected maximum full-flow 
operating pressure, rounded to the nearest integer, in psig. If the 
expected maximum full-flow operating pressure is not known, then 
adjust the backpressure of the system so that the measured discharge 
pressure is 65 psig. Allow the unit to remain at this setting for 15 
minutes to allow the unit to thermally stabilize. Then measure and 
record discharge pressure and actual volume flow rate at the 
starting pressure.
    C.2. Adjust the backpressure of the system to increase the 
discharge pressure by 2 psig from the previous value, allow the unit 
to remain at this setting for a minimum of 2 minutes, and proceed to 
section III.C.3 of this appendix.
    C.3. If the unit is now in an unloaded condition, end the test 
and proceed to section III.C.4 of this appendix. If the unit is not 
in an unloaded condition, measure discharge pressure and actual 
volume flow rate, and repeat section III.C.2 of this appendix.
    C.4. Of the discharge pressures recorded under stabilized 
conditions in sections III.C.1 through III.C.3 of this appendix, 
identify the largest. This is the maximum full-flow operating 
pressure. Determine the full-load operating pressure as a self-
declared value greater than or equal to the lesser of (A) 90 percent 
of the maximum full-flow operating pressure, or (B) 10 psig less 
than the maximum full-flow operating pressure.
    C.5. The full-load actual volume flow rate is the actual volume 
flow rate measured at the full-load operating pressure. If the self-
declared full-load operating pressure falls on a previously tested 
value of discharge pressure, then use the previously measured actual 
volume flow rate as the full-load actual volume flow rate. If the 
self-declared full-load operating pressure does not fall on a 
previously tested value of discharge pressure, then adjust the 
backpressure of the system to the self-declared full-load operating 
pressure and allow the unit to remain at this setting for a minimum 
of 2 minutes. The measured actual volume flow rate at this setting 
is the full-load actual volume flow rate.

[FR Doc. 2016-29427 Filed 1-3-17; 8:45 am]
BILLING CODE 6450-01-P