Energy Conservation Program: Test Procedures for Walk-In Coolers and Walk-In Freezers, 186-218 [E9-30884]

Agencies

• DEPARTMENT OF ENERGY

[Federal Register Volume 75, Number 1 (Monday, January 4, 2010)]
[Proposed Rules]
[Pages 186-218]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E9-30884]



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Part II





Department of Energy





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10 CFR Part 431



Energy Conservation Program: Test Procedures for Walk-In Coolers and 
Walk-In Freezers; Proposed Rule

Federal Register / Vol. 75, No. 1 / Monday, January 4, 2010 / 
Proposed Rules

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DEPARTMENT OF ENERGY

10 CFR Part 431

[Docket No. EERE-2008-BT-TP-0014]
RIN 1904-AB85


Energy Conservation Program: Test Procedures for Walk-In Coolers 
and Walk-In Freezers

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

ACTION: Notice of proposed rulemaking and public meeting.

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SUMMARY: Pursuant to the Energy Policy and Conservation Act, as 
amended, the U.S. Department of Energy (DOE) is proposing test 
procedures for measuring the energy consumption of walk-in coolers and 
walk-in freezers (collectively ``walk-in equipment'' or ``walk-
in(s)''), definitions to delineate the products covered by the test 
procedures, and provisions (including a sampling plan) for 
manufacturers to implement the test procedures. The notice also 
addresses enforcement issues as they relate to walk-in equipment. 
Concurrently, DOE is undertaking an energy conservation standards 
rulemaking for this equipment. Any data gathered through the use of the 
test procedure adopted by DOE will be used in evaluating any potential 
standards for this equipment. Once these standards are promulgated, the 
adopted test procedures will be used to determine equipment efficiency 
and compliance with the standards.

DATES: DOE will hold a public meeting in Washington, DC on Thursday, 
February 11, 2010, beginning at 9 a.m. DOE must receive requests to 
speak at the meeting before 4 p.m., Thursday, January 28, 2010. DOE 
must receive a signed original and an electronic copy of statements to 
be given at the public meeting before 4 p.m., Thursday, January 28, 
2010.
    DOE will accept comments, data, and information regarding this 
notice of proposed rulemaking (NOPR) before or after the public 
meeting, but no later than March 22, 2010. See section V, ``Public 
Participation,'' of this NOPR for details.

ADDRESSES: The public meeting will be held at the U.S. Department of 
Energy, Forrestal Building, Room 8E-089, 1000 Independence Avenue, SW., 
Washington, DC 20585-0121. To attend the public meeting, please notify 
Ms. Brenda Edwards at (202) 586-2945. Please note that foreign 
nationals participating in the public meeting are subject to advance 
security screening procedures, requiring a 30-day advance notice. If 
you are a foreign national and wish to participate in the public 
meeting, please inform DOE as soon as possible by contacting Ms. Brenda 
Edwards at (202) 586-2945 so that the necessary procedures can be 
completed.
    Any comments submitted must identify the NOPR for Test Procedures 
for Walk-in Coolers and Freezers, and provide docket number EERE-2008-
BT-TP-0014 and/or Regulation Identifier Number (RIN) 1904-AB85. 
Comments may be submitted using any of the following methods:
    1. Federal eRulemaking Portal: https://www.regulations.gov. Follow 
the instructions for submitting comments.
    2. E-mail: WICF-2008-TP-0014@hq.doe.gov. Include the docket number 
EERE-2008-BT-TP-0014 and/or RIN 1904-AB85 in the subject line of the 
message.
    3. Postal Mail: Ms. Brenda Edwards, U.S. Department of Energy, 
Building Technologies Program, Mailstop EE-2J, 1000 Independence 
Avenue, SW., Washington, DC 20585-0121. Please submit one signed 
original paper copy.
    4. Hand Delivery/Courier: Ms. Brenda Edwards, U.S. Department of 
Energy, Building Technologies Program, 950 L'Enfant Plaza, SW., 6th 
Floor, Washington, DC 20024. Please submit one signed original paper 
copy.
    For detailed instructions on submitting comments and additional 
information on the rulemaking process, see section V, ``Public 
Participation,'' of this document.
    Docket: For access to the docket to read background documents or 
comments received, visit the U.S. Department of Energy, Resource Room 
of the Building Technologies Program, 950 L'Enfant Plaza, SW., 6th 
Floor, Washington, DC 20024, (202) 586-2945, between 9 a.m. and 4 p.m. 
Monday through Friday, except Federal holidays. Please call Ms. Brenda 
Edwards at the above telephone number for additional information 
regarding visiting the Resource Room.

FOR FURTHER INFORMATION CONTACT: Mr. Charles Llenza, U.S. Department of 
Energy, Building Technologies Program, EE-2J, 1000 Independence Avenue, 
SW., Washington, DC 20585-0121, (202) 586-2192, 
Charles.Llenza@ee.doe.gov or Mr. Michael Kido, Esq., U.S. Department of 
Energy, Office of General Counsel, GC-72, 1000 Independence Avenue, 
SW., Washington, DC 20585- 0121, (202) 586-8145, 
Michael.Kido@hq.doe.gov.

SUPPLEMENTARY INFORMATION:

Table of Contents

I. Authority and Background
II. Summary of the Proposal
III. Discussion
    A. Overall Approach
    1. Basic Model
    2. Approach Option 1: Test the Unit as a Whole
    3. Approach Option 2: Allow Manufacturers To Use Alternative 
Energy Determination Methods (AEDMs)
    4. Proposed Option and Recommendation: Separate Envelope and 
Refrigeration Tests
    B. Envelope
    1. Overview of the Test Procedure
    2. Test Methods
    a. Insulation
    b. Air Infiltration
    c. Steady-State Infiltration Test
    3. Calculations
    a. Energy Efficiency Ratio
    b. Heat Gain Through the Envelope Due to Conduction
    c. Heat Gain Due to Infiltration
    d. Envelope Component Electrical Loads
    e. Normalization
    f. Daily Energy Consumption Coefficients
    C. Refrigeration System
    1. Overview of the Test Procedure
    2. Test Conditions
    3. Test Methods
    4. Measurements and Calculations
    D. Compliance, Certification, and Enforcement
    1. Provisions for Energy Conservation Standards Developed by the 
Department of Energy
    2. Provisions for Existing Design Standards Prescribed by 
Congress
IV. Regulatory Review
    A. Review Under Executive Order 12866
    B. Review Under the National Environmental Policy Act
    C. Review Under the Regulatory Flexibility Act
    D. Review Under the Paperwork Reduction Act
    E. Review Under the Unfunded Mandates Reform Act of 1995
    F. Review Under the Treasury and General Government 
Appropriations Act, 1999
    G. Review Under Executive Order 13132
    H. Review Under Executive Order 12988
    I. Review Under the Treasury and General Government 
Appropriations Act, 2001
    J. Review Under Executive Order 13211
    K. Review Under Executive Order 12630
    L. Review Under Section 32 of the Federal Energy Administration 
(FEA) Act of 1974
V. Public Participation
    A. Attendance at Public Meeting
    B. Procedure for Submitting Requests to Speak
    C. Conduct of Public Meeting
    D. Submission of Comments
    E. Issues on Which DOE Seeks Comment
    1. Test Procedure Improvements
    2. Basic Model
    3. Separate Envelope and Refrigeration Tests
    4. Definition of Envelope
    5. Effect of Impermeable Skins on Long-Term R Value
    6. Measuring Long-Term R Value Using American Society for 
Testing and Materials (ASTM) C1303-08
    7. Infiltration

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    8. Nominal Coefficient of Performance of Refrigeration
    9. Measuring the U Value of glass
    10. Floor R Value
    11. Electrical Duty Cycle
    12. Normalization Factor
    13. Daily Energy Consumption Coefficients
    14. Definition of Refrigeration System
    15. Measurements and Calculations of Energy Use of Refrigeration 
Systems
    16. Impacts on Small Businesses
VI. Approval of the Office of the Secretary

I. Authority and Background

    Title III of the Energy Policy and Conservation Act of 1975, as 
amended (EPCA or the Act) sets forth a variety of provisions designed 
to improve energy efficiency. Part B of Title III (42 U.S.C. 6291-6309) 
provides for the Energy Conservation Program for Consumer Products 
Other Than Automobiles. The National Energy Conservation Policy Act 
(NECPA), Public Law 95-619, amended EPCA to add Part C of Title III, 
which established an energy conservation program for certain industrial 
equipment. (42 U.S.C. 6311-6317) (These parts were subsequently 
redesignated as Parts A and A-1, respectively, for editorial reasons.) 
Section 312 of the Energy Independence and Security Act of 2007 (EISA 
2007) further amended EPCA by adding certain equipment to this energy 
conservation program, including walk-in coolers and walk-in freezers 
(collectively ``walk-in equipment'' or ``walk-ins''), the subject of 
this rulemaking. (42 U.S.C. 6311(1), (2), 6313(f) and 6314(a)(9))
    EPCA defines walk-in equipment as follows:
    (A) In general.--
    The terms ``walk-in cooler'' and ``walk-in freezer'' mean an 
enclosed storage space refrigerated to temperatures, respectively, 
above, and at or below 32 degrees Fahrenheit that can be walked into, 
and has a total chilled storage area of less than 3,000 square feet.
    (B) Exclusion.--
    The terms ``walk-in cooler'' and ``walk-in freezer'' do not include 
products designed and marketed exclusively for medical, scientific, or 
research purposes. (42 U.S.C. 6311(20))
    Walk-ins covered by this rulemaking may be located indoors or 
outdoors. They may be used exclusively for storage, but they may also 
have transparent doors or panels for the purpose of displaying stored 
items. Examples of items that may be stored in walk-ins include, but 
are not limited to, food, beverages, and flowers. DOE notes that any 
equipment that meets the above definition is potentially subject to 
regulation.
    Under the Act, the overall program consists essentially of the 
following parts: testing, labeling, and Federal energy conservation 
standards. The testing requirements for covered equipment consist of 
test procedures, prescribed under EPCA. These test procedures are used 
in several different ways: (1) Any data from the use of these 
procedures are used as a basis in developing standards for covered 
products or equipment; (2) the test procedure is used when determining 
equipment compliance with those standards; and (3) manufacturers of 
covered equipment must use the procedure to establish that their 
equipment complies with energy conservation standards promulgated 
pursuant to EPCA and when making representations about equipment 
efficiency.
    Section 343 of EPCA (42 U.S.C. 6314) sets forth generally 
applicable criteria and procedures for DOE's adoption and amendment of 
such test procedures. That provision requires that the test procedures 
promulgated by DOE be reasonably designed to produce test results which 
reflect energy efficiency, energy use, and estimated operating costs of 
the covered equipment during a representative average use cycle. It 
also requires that the test procedure not be unduly burdensome to 
conduct. See 42 U.S.C. 6314(a)(2). As part of the process for 
promulgating a test procedure, DOE must publish the procedure that it 
plans to propose and offer the public an opportunity to present oral 
and written comments on them. Consistent with Executive Order 12889 and 
EPCA (see 42 U.S.C. 6314(b)), DOE provides a minimum comment period of 
75 days on a proposed test procedure. As to the test procedures for 
walk-in equipment, EPCA prescribes the following requirements:
    (A) In general.--
    For the purpose of test procedures for walk-in coolers and walk-in 
freezers:
    (i) The R value shall be the 1/K factor multiplied by the thickness 
of the panel.
    (ii) The K factor shall be based on ASTM [American Society for 
Testing and Materials] test procedure C518-2004.
    (iii) For calculating the R value for freezers, the K factor of the 
foam at 20 [deg]F (average foam temperature) shall be used.
    (iv) For calculating the R value for coolers, the K factor of the 
foam at 55 [deg]F (average foam temperature) shall be used.
    (B) Test Procedure.--
    (i) In general.--Not later than January 1, 2010, the Secretary 
shall establish a test procedure to measure the energy-use of walk-in 
coolers and walk-in freezers.
    (ii) Computer modeling.--The test procedure may be based on 
computer modeling, if the computer model or models have been verified 
using the results of laboratory tests on a significant sample of walk-
in coolers and walk-in freezers. (42 U.S.C. 6314(a)(9))
    On February 4, 2009, DOE held a public meeting on the framework 
document it issued concerning the DOE rulemaking to evaluate walk-in 
equipment for energy conservation standards. See 74 FR 411 (Jan. 6, 
2009) and 74 FR 1992 (Jan. 14, 2009). Both the framework document and 
meeting discussed the possible test procedures for this equipment that 
DOE was considering at that time, and gave interested parties an 
opportunity to submit comments. Today's notice addresses those comments 
and proposes test procedures for walk-in equipment.

II. Summary of the Proposal

    In today's notice, DOE proposes to adopt new test procedures for 
determining the energy use of walk-in cooler and walk-in freezer 
equipment to address the statutory requirement to establish a test 
procedure by January 1, 2010. (42 U.S.C. 6314(a)(9)(B)) Concurrently, 
DOE is undertaking an energy conservation standards rulemaking for 
walk-in equipment to address the statutory requirement to establish 
performance standards no later than January 1, 2012. (42 U.S.C. 
6313(f)(4)(A)) DOE will use any data resulting from use of the test 
procedure that DOE adopts to evaluate potential performance standards 
for this equipment. Furthermore, once performance standards are issued, 
manufacturers would be required to use the test procedures to determine 
compliance with such standards and for any representations regarding 
the energy use of walk-in equipment they produce. This test procedure, 
once adopted, would serve as the means for ascertaining compliance with 
the appropriate standards in an enforcement action.
    For the reasons described below, DOE proposes to adopt a test 
procedure that contains two separate test methods. This approach is 
necessary because there are typically two manufacturers of walk-in 
equipment: One who manufactures the envelope (i.e., the insulated box 
in which the refrigerated or frozen items are stored) and one who 
manufactures the refrigeration system (i.e., the mechanism that 
provides the means by which to feed chilled air into the envelope). One 
method determines the

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energy consumption of the refrigeration system of the walk-in cooler or 
freezer. The other method determines the energy consumption of the 
envelope, which is the sum of the energy use associated with heat 
transmission through the envelope in the form of conduction through the 
walls and air infiltration through openings, and the power consumed by 
electrical components that are part of the envelope. Each of the two 
components, the refrigeration system and the envelope, is considered 
separately and the energy consumption of each component is calculated 
using the applicable test procedure. DOE believes that the approach is 
consistent with the requirements in EPCA because the results of the two 
tests will represent, in the aggregate, the total energy consumption of 
walk-in coolers and freezers.
    Using this approach, DOE believes that the proposed test procedures 
will adequately measure the energy consumption of walk-in equipment by 
capturing the energy consumption of both components. However, DOE 
requests comment from stakeholders on improvements or changes to the 
proposed test procedures and will consider modifications that improve 
the accuracy, appropriateness for the equipment being tested, 
repeatability of test results for the same or similar units, 
comparability of results for different types of units, burden on 
manufacturers, precision of language, or other elements of the 
procedures. In submitting comments, interested parties should state the 
nature of the recommended modification and explain how it would improve 
upon the test procedure proposed in this NOPR. Commenters should also 
submit data, if any, to support their positions.
    DOE's adoption of the proposed test procedures, which would be 
applicable to all walk-in equipment, would not necessarily mean that 
DOE would adopt a single energy conservation standard or set of 
labeling requirements for all walk-in equipment. In the separate 
rulemaking proceeding concerning energy conservation standards for 
walk-in equipment, DOE may divide such equipment into classes and may 
conclude that standards are not warranted for some classes of equipment 
that are within the scope of today's test procedure. Furthermore, DOE 
may create a separate standard for each class of equipment that 
includes a utility- or performance-related feature that another 
equipment class lacks, and that affects energy consumption.
    DOE also notes that the National Technology Transfer and 
Advancement Act of 1995 (Pub. L. 104-113) directs Federal agencies to 
use voluntary consensus standards in lieu of Government standards 
whenever possible. Consequently, as described in the following 
paragraphs, DOE attempted to incorporate by reference in its test 
procedures generally accepted rules or recognized industry standards 
such as those issued by the Air-Conditioning, Heating and Refrigeration 
Institute (AHRI), the American Society of Heating, Refrigerating, and 
Air Conditioning Engineers (ASHRAE), the American National Standards 
Institute (ANSI), and/or ASTM International (ASTM), that provide either 
specific aspect(s) of the test procedure, or the complete test 
procedure, for the specified equipment.

III. Discussion

    In the following section, DOE describes the overall approach it 
proposes to follow with respect to the adoption of a test procedure for 
walk-ins. This approach results from the characteristics of walk-in 
equipment and is based in part on the basic model definition that DOE 
currently uses to help establish testing requirements for manufacturers 
to follow. The following section also addresses issues raised by 
commenters, which included: Manufacturers (Craig Industries (Craig), 
Manitowoc, Nor-Lake); trade associations (AHRI); utility companies 
(Southern California Edison (SCE), Sacramento Municipal Utility 
District (SMUD), San Diego Gas and Electric (SDG&E)); and advocacy 
groups (Appliance Standards Awareness Project (ASAP), American Council 
for an Energy-Efficient Economy (ACEEE), Natural Resources Defense 
Council (NRDC), Northwest Energy Efficiency Alliance (NEEA)).

A. Overall Approach

    DOE developed today's proposed test procedure to set forth the 
testing requirements for walk-in equipment. In the framework document, 
DOE considered two overall approaches manufacturers could take to 
determine the energy consumption of walk-in coolers and freezers. 
First, DOE considered using a modified version of the Air-Conditioning 
and Refrigeration Institute (ARI) Standard 1200-2006, ``Performance 
Rating of Commercial Refrigerated Display Merchandisers and Storage 
Cabinets'' (ARI 1200-2006), which uses the test method described in the 
American National Standards Institute/American Society of Heating, 
Refrigerating, and Air Conditioning Engineers (ANSI/ASHRAE) Standard 
72-2005, ``Method of Testing Commercial Refrigerators and Freezers'' 
(ANSI/ASHRAE 72-2005). Second, DOE considered allowing manufacturers to 
determine the efficiency of some of their products using alternative 
efficiency determination methods (AEDMs). (An AEDM is a predictive 
mathematical model, developed from engineering analyses of design data 
and substantiated by actual test data, which represents the energy 
consumption characteristics of one or more basic models.)
    DOE received comments on these proposed approaches, many of which 
were opposed to both approaches. The comments DOE received, and DOE's 
responses, are discussed in more detail below. After considering these 
comments and reviewing the matter further, DOE is proposing separate 
test procedures for the envelope (insulated box) and the refrigeration 
system. DOE discusses the details of its proposals and addresses 
manufacturer comments in the following subsections.
1. Basic Model
    Under EPCA, which prohibits the distribution in commerce of covered 
equipment that do not comply with the applicable standard, each model 
of covered equipment is potentially subject to energy efficiency 
testing consistent with the relevant requirements for that equipment. 
However, walk-in manufacturers typically make numerous envelope models 
and, even within a single model, the units are often customized in 
multiple ways. To reduce this potential burden, DOE proposes following 
the approach it has used for other equipment by allowing manufacturers 
to group equipment or models with essentially identical energy 
consumption characteristics into a single family of models, called a 
basic model. This concept has been established both for residential 
appliances and commercial and industrial equipment covered under EPCA. 
(See Title 10 of the Code of Federal Regulations (10 CFR) 430.2, which 
covers 26 products, and 10 CFR 431.12, 431.62, 431.132, 431.172, 
431.192, 431.202, 431.222, 431.262, and 431.292, which cover various 
equipment.)
    Walk-in refrigeration systems are often manufactured according to 
the same basic blueprint design, and any particular model could 
incorporate modifications that do not significantly affect the energy 
efficiency of the system. For example, manufacturers often sell systems 
that are designed to operate at different voltages. This allows them to 
market to customers with different electrical capabilities. The 
operating voltage affects the energy

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efficiency of the system, but very minimally. If manufacturers were 
required to test the efficiency of each model with a different feature, 
the testing burden would be significant, but yield effectively 
redundant results. Therefore, DOE provides for testing of a basic model 
of refrigeration systems that may not be identical, but would not have 
any electrical, physical, or functional characteristics that 
significantly affect energy consumption. Features that may affect the 
energy consumption of walk-in cooler and freezer refrigeration systems 
include compressor size, fan motor type, and heat exchanger coil 
dimensions.
    Walk-in envelopes are often manufactured according to the same 
basic design, but the equipment is so highly customized that each walk-
in a manufacturer builds may be unique, and potentially subject to 
testing as a separate basic model. For instance, changing the size of 
the envelope would affect the energy consumption obtained by the test 
procedure, even if the construction methods and materials were the 
same. To address this possibility, DOE proposes (1) grouping walk-in 
envelopes with essentially identical construction methods, materials, 
and components into a single basic model, and (2) adopting a 
calculation methodology for determining the energy consumption of units 
within the basic model. This methodology would require a manufacturer 
to test one unit of the basic model and then calculate daily energy 
consumption coefficients (DECCs) for that basic model according to the 
test procedure. The manufacturer could then apply those DECCs to other 
units within a basic model even if those units were not identical, to 
obtain the energy consumption of those units. Although units within a 
basic model need not share identical dimensions, finishes, and non-
energy-related features (e.g., shelving or door kick plates), they must 
have been manufactured using substantially the same construction 
methods, materials, and components. A few examples of factors that 
would necessitate a different basic model include changing the type of 
insulating foam, the method of locking together the panels of the walk-
in envelope, or the electrical characteristics of the lighting. 
Examples of factors that may not constitute a different basic model 
include the type of exterior metal finish, the dimensions of the 
envelope, and the number of doors of the same type. The exterior metal 
finish would not have a substantial impact on the efficiency of the 
envelope. Dimensions and number of doors, on the other hand, would be 
accounted for in the energy consumption calculation using the DECCs 
from the unit of the basic model that was tested. (See section 
III.B.3.f for further discussion of DECCs.)
    All of the equipment included in a basic model must be within the 
same equipment class. Components of similar design may be substituted 
in a basic model without requiring additional testing if the 
represented energy consumption measurements continue to satisfy the 
provisions for sampling and testing. Only representative samples within 
each basic model would be tested.
    For walk-ins, DOE is considering adopting the following definition 
of ``basic model:'' ``Basic Model means all units of a given type of 
walk-in equipment manufactured by a single manufacturer, and--(1) With 
respect to envelopes, which do not have any differing construction 
methods, materials, components, or other characteristics that 
significantly affect the energy consumption characteristics. (2) With 
respect to refrigeration systems, which have the same primary energy 
source and which do not have any differing electrical, physical, or 
functional characteristics that significantly affect energy 
consumption.'' DOE requests comment on its proposed basic model 
approach.
2. Approach Option 1: Test the Unit as a Whole
    In the framework document, DOE considered developing a test 
procedure for walk-ins by adapting an existing test procedure for 
commercial refrigeration equipment, such as ARI 1200-2006. This 
approach would require an entire walk-in cooler or freezer to be 
physically tested within a controlled test chamber in order to evaluate 
its energy consumption over a period of time. During the standards 
framework public meeting, DOE requested comments on the feasibility of 
this approach. Interested parties responded with significant 
reservations about using a modified version of the ARI 1200-2006 test 
procedure, citing crucial differences between walk-ins and commercial 
refrigeration equipment.
    In particular, interested parties noted that walk-ins are 
physically different from commercial refrigerators in ways that make a 
full-system test burdensome or impractical. Manitowoc stated that for 
very large walk-ins, around the 3,000-square-foot limit in the EPCA 
definition, manufacturers might not have a large enough test facility 
to make the measurements necessary for the ARI 1200-2006 test procedure 
in a controlled environment. (Manitowoc, Public Meeting Transcript, No. 
15 at p. 59) (In this and subsequent citations, ``Public Meeting 
Transcript'' refers to the transcript of the February 4, 2009, public 
meeting on standards for walk-in coolers and freezers. ``No. 15'' 
refers to the document number of the transcript in the Docket for the 
DOE rulemaking on standards for walk-in coolers and freezers, Docket 
No. EERE-2008-BT-TP-0014; and the page references refer to the place in 
the transcript where the statement preceding appears.) Kason Industries 
also stated that it would be practically impossible to have a large 
enough controlled climate enclosure to test medium to large walk-ins, 
and added that if a walk-in were a free-standing structure, testing it 
as a whole building would not be practical. (Kason, No. 16 at pp. 1, 4) 
(In this and subsequent citations, the document number refers to the 
number of the comment in the Docket for the DOE rulemaking on standards 
for walk-in coolers and freezers, Docket No. EERE-2008-BT-TP-0014; and 
the page references refer to the place in the document where the 
statement preceding appears.) The Air-Conditioning, Heating, and 
Refrigeration Institute (AHRI) stated that the proposed test procedures 
were not practical because it would be costly to physically test walk-
ins. (AHRI, No. 33 at p. 2)
    Commenters also noted that the market for walk-in coolers and 
freezers is structured differently from the market for commercial 
refrigeration equipment, making a direct comparison between these types 
of equipment difficult. Manitowoc stated that the envelope of a 
particular unit of walk-in equipment may be manufactured by one company 
and the refrigeration system by another company. ARI 1200-2006 would 
require the two systems to be integrated before running the test, which 
would place the burden on the installer or someone beyond the 
manufacturer of the subsystems. (Manitowoc, Public Meeting Transcript, 
No. 15 at p. 59) AHRI agreed that the ARI 1200-2006 standard might not 
be the right approach and that DOE would need to separate the 
mechanical system from the envelope. (AHRI, Public Meeting Transcript, 
No. 15 at p. 62)
    In addition to these concerns, commenters identified a deficiency 
in the ARI 1200-2006 test procedure. SCE stated that the majority of 
potential energy savings can be achieved using floating head pressure 
and variable-speed evaporator fans, both of which have varying effects 
depending on the time of day and the regional climate

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because the savings associated with each feature can depend on the 
ambient temperature and usage patterns of the walk-in over the course 
of a day. Because ARI 1200-2006 is a steady-state test, it would not 
capture the energy savings from either option. (SCE, Public Meeting 
Transcript, No. 15 at p. 63) AHRI agreed that the test procedure should 
capture savings from a control strategy or variable-speed components, 
both of which could optimize the operation of the walk-in for a variety 
of ambient conditions and usage patterns. An example of optimization 
would be allowing elements of the refrigeration system to turn off or 
reduce their operation at night when the walk-in is not being accessed. 
(AHRI, No. 33 at p. 2)
    After considering these comments, DOE believes that an adapted 
version of ARI 1200-2006 would be inadequate to use as the test 
procedure for walk-in equipment. ARI 1200-2006 contains too many 
limitations and practical difficulties that would make it very 
difficult to effectively implement as a workable test procedure for 
walk-in. Therefore, DOE is no longer considering this approach.
3. Approach Option 2: Allow Manufacturers To Use Alternative Energy 
Determination Methods (AEDMs)
    DOE's framework document also presented an alternative that would 
permit the use of an AEDM when determining walk-in energy consumption 
to help relieve the testing burden on manufacturers. An AEDM is a 
predictive mathematical model, developed from engineering analyses of 
design data and substantiated by actual test data which represents the 
energy consumption characteristics of one or more basic models. After 
confirming the accuracy of an AEDM, the manufacturer would apply the 
AEDM to basic models to determine their energy consumption without 
conducting any physical testing.
    Applying this approach, the manufacturer would confirm the accuracy 
of the AEDM using the following method. First, the manufacturer would 
determine through actual testing the energy consumption of a certain 
number of its basic models that would be selected in accordance with 
criteria specified in the procedure. Second, the manufacturer would 
apply the AEDM to these same basic models. The AEDM would be considered 
sufficiently accurate only if: (1) The predicted total energy 
consumption of each of these basic models, calculated by applying the 
AEDM, is within a certain percentage of the total energy consumption 
determined from the testing of that basic model; and (2) the average of 
the predicted total energy consumption for the tested basic models, 
calculated by applying the AEDM, is within a certain percent of the 
average of the total energy consumption determined from testing these 
basic models. Under this approach, once the manufacturer verifies the 
accuracy of the AEDM, the manufacturer can use the AEDM to determine 
the energy consumption of other basic models without having to test 
those models. DOE requested comments on this approach during the 
framework public meeting, both in terms of how to implement the 
approach and whether such an approach was valid for walk-ins at all. 
DOE received several relevant comments, which are described and 
addressed below.
    Given the unprecedented nature of using an AEDM to rate this type 
of equipment, DOE needed to determine both an appropriate sample size 
for verifying an AEDM and an acceptable minimum accuracy percentage for 
an AEDM. During the framework public meeting, DOE requested comments on 
these two values. AHRI could not provide feedback on how accurate the 
AEDM should be because DOE had not yet determined the test metric to 
apply. (AHRI, Public Meeting Transcript, No. 15 at p. 69) Manitowoc 
agreed that the test methodology needs to be established and 
experiments conducted to collect data that would be used to validate 
AEDMs. (Manitowoc, Public Meeting Transcript, No. 15 at p. 70) In a 
written comment, Kason Industries stated that an AEDM with a minimum 
accuracy of 66 percent would encompass a majority of the wide range of 
walk-in cooler and freezer applications. (Kason, No. 16 at p. 2) No 
commenter provided substantive data that DOE would use in its analysis 
to help support a particular sample size. Accordingly, DOE did not 
receive enough data from stakeholders that could help it determine an 
appropriate sample size or accuracy range to substantiate an AEDM.
    During the public meeting, DOE also requested comments on the 
possibility of allowing manufacturers to take this approach to rate 
their walk-ins. Kason stated that an AEDM procedure would be preferable 
to using a physical test because the majority of walk-ins are custom-
made by size, ambient temperature, and refrigeration demands. 
Therefore, it would be very difficult to create a test procedure that 
encompasses the range of walk-in equipment. (Kason, No. 16 at p. 1) 
Kason suggested that, as an alternative to testing the system as a 
whole, an AEDM could be based on determining efficiencies and 
performance characteristics for the principal components of a walk-in 
considering three factors: insulation and air tightness of the external 
envelope and door, efficiency of the refrigeration system for steady-
state storage load (similar to the efficiency rating system for HVAC), 
and performance of the refrigeration system for removal of process heat 
and equipment-generated heat. (Kason, No. 16 at p. 2)
    Other interested parties commented that allowing manufacturers to 
develop their own calculation methodology or software program as an 
AEDM could be problematic. Owens Corning questioned whether there could 
be a comparison among ratings published by manufacturers that developed 
different AEDMs. (Owens Corning, Public Meeting Transcript, No. 15 at 
p. 64) Craig stated that manufacturers who devise their own test 
procedures could write them in a way that benefits their own company. 
(Craig, Public Meeting Transcript, No. 15 at pp. 68-69) SCE stated that 
allowing manufacturers to develop their own software as an AEDM could 
be unfair to manufacturers with fewer resources, because the software 
is expensive and time-consuming to develop. Instead, SCE suggested that 
it would be better to have a transparent analysis method with the 
algorithms available to all participants and the data in a standardized 
format. (SCE, Public Meeting Transcript, No. 15 at p. 71) Craig replied 
that many manufacturers have sizing programs, which may be proprietary, 
to calculate the total load of the walk-in, accessories, and product 
load, and to size the refrigeration system properly for the energy 
requirements of the envelope. (Craig, Public Meeting Transcript, No. 15 
at pp. 77-78 and No. 22 at p. 4) However, Craig stressed that requiring 
manufacturers to follow the same model developed or approved by DOE, 
would be fair to different manufacturers and provide consistent 
information to end users. (Craig, Public Meeting Transcript, No. 15 at 
p. 94 and No. 22 at p. 5)
    ACEEE asserted that it would be difficult for DOE to work with many 
proprietary models, some of which might be difficult to verify. (ACEEE, 
Public Meeting Transcript, No. 15 at p. 94) NEEA also said that if an 
AEDM were used, the software should be equally available to all 
manufacturers and code officials for the purpose of determining 
compliance. (NEEA, No. 18 at p. 3) Crown Tonka stated that a standard 
configuration and standard test should be developed to create a 
baseline

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for energy usage, with normalizing factors associated with 
configuration changes. (Crown Tonka, No. 23 at p. 1) Owens Corning 
reiterated that a single AEDM should be accepted to keep comparisons 
consistent. (Owens Corning, No. 31 at p. 2)
    DOE had previously understood that manufacturers would develop 
their own AEDMs and would verify their accuracy by testing a small 
number of walk-in models. However, as discussed above, most interested 
parties indicated that allowing manufacturers to develop their own 
rating calculations or software could be problematic, despite the fact 
that the calculations and software would need to be verified. 
Therefore, DOE does not propose to allow manufacturers to develop their 
own AEDMs. Instead, DOE developed its own calculation methodology for 
manufacturers to use in rating similar, but not identical, units of 
walk-in equipment. For further discussion on this methodology, see 
section III.B.3.f.
4. Proposed Option and Recommendation: Separate Envelope and 
Refrigeration Tests
    Both methods described above were predicated on the assumption that 
an entire walk-in unit is manufactured by a single entity, which could 
either test the walk-in as a whole according to ARI Standard 1200-2006, 
or calculate the overall efficiency using an AEDM. In fact, as DOE 
learned, most walk-ins have two main manufacturers: One who 
manufactures the envelope and one who manufactures the refrigeration 
system that cools the interior of the envelope. (Other manufacturers 
may be involved in producing secondary components --such as fan 
assemblies or lighting-- that are then purchased by the main 
manufacturers and incorporated as part of the refrigeration system or 
envelope.) These two parts are manufactured separately, and are often 
assembled together in the field by a third-party contractor who may not 
have been responsible for the manufacture of either part, and who may 
not have testing or evaluation capabilities. Because of this situation, 
DOE developed, and is proposing, a different approach for testing walk-
ins, as described below.
    Specifically, DOE proposes separate test procedures for the 
envelope and the refrigeration system. The envelope manufacturer would 
be responsible for testing the envelope according to the envelope test 
procedure, and the refrigeration system manufacturer would be 
responsible for testing the refrigeration system according to the 
refrigeration system test procedure. Such an approach would be more 
likely to generate usable data in support of standards for both the 
envelope and the refrigeration system during the development of any 
energy conservation standards for walk-in coolers and freezers. The two 
test procedures are described in sections III.B and III.C, 
respectively.
    There are several advantages to this approach. First, having 
separate test procedures would allow individual component manufacturers 
to test their components--the envelope and the refrigeration system. 
These component manufacturers would be more likely to have access to 
the resources, equipment, and personnel needed to conduct the tests. On 
the other hand, the ``manufacturer'' of an entire walk-in system (i.e., 
envelope and refrigeration system combined), could be a third party: A 
contractor who assembles the walk-in from the separate components and/
or installs it in the field. This third-party assembler may even be the 
end-user or owner of the equipment. If a walk-in is assembled in the 
field, testing of the entire assembled system may not be feasible due 
to lack of expertise and the need for additional testing equipment.
    Second, this approach would result in a significantly reduced 
testing burden while ensuring compliance with any standard DOE may 
develop. There are many more assemblers and installers of walk-ins than 
there are component manufacturers. Because EPCA requires manufacturers 
to demonstrate compliance with energy conservation standards, 
interpreting the term ``manufacturer'' to include assemblers and 
installers, who may be contractors or end-users, to demonstrate 
compliance with a standard would impose the compliance burden on 
entities who, more likely than not, may not have participated in the 
design and manufacture (and therefore energy efficiency) of the 
component parts. Furthermore, this approach would create substantial 
difficulties for DOE to enforce any standards it promulgates for walk-
in equipment. While DOE considered the possibility that including 
assemblers and installers as parties involved in the manufacture of 
this equipment could encourage these parties to take steps to ensure 
that compliant equipment is installed, at this time, DOE believes that 
the testing burdens are best met by the envelope and refrigeration 
system manufacturers for the reasons discussed above. Accordingly, 
under today's proposal, only envelope and refrigeration system 
manufacturers would need to demonstrate compliance with any proposed 
standard through the use of the test procedure. (DOE notes that 
possible remedial action for failing to satisfy these requirements 
include civil penalties and injunctive relief to prevent the continued 
sale and distribution of noncompliant equipment.) (42 U.S.C. 6303-6304)
    DOE requests comment on this proposed approach and whether it is 
appropriate for walk-ins.

B. Envelope

    As described earlier, the envelope consists of the insulated box in 
which the stored items reside. The following discussion describes in 
greater detail the test procedure DOE is proposing for the walk-in 
envelope. DOE also addresses issues raised by interested parties.
    This procedure contains the proposed methodology for evaluating the 
performance characteristics of the insulation as well as methods for 
testing thermal energy gains related to air infiltration caused by use 
(door openings) and imperfections in wall interfaces or door gasketing 
material. Heat gain due to internal electrical components is an 
additional consideration.
    The proposed procedure utilizes the data obtained to calculate a 
measure of energy use associated with the envelope. In other words, the 
test procedure calculates the effect of the envelope's characteristics 
and components on the energy consumption of the walk-in as a whole. 
This includes the energy consumption of electrical components present 
in the envelope (such as lights) and variation in the energy 
consumption of the refrigeration system due to heat loads introduced as 
a function of envelope performance, such as conduction of heat through 
the walls of the envelope. The effect on the refrigeration system is 
determined by calculating the energy consumption of a theoretical, or 
nominal, refrigeration system, were it to be paired with the tested 
envelope. Using the same nominal refrigeration system characteristics 
allows for direct comparison of the performance of walk-in envelopes 
across a range of sizes, product classes, and levels of feature 
implementation.
    The test procedure obtains a metric of energy use associated with 
the envelope of a walk-in cooler or freezer, consistent with the 
statutory requirement (42 U.S.C. 6314(a)(9)(B)(i)). For purposes of 
this rulemaking, DOE interprets the term ``energy use'' to describe the 
sum of (a) the electrical energy consumption of envelope components and 
(b) the energy consumption of the walk-in refrigeration equipment that 
is

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contributed by the performance of the envelope.
1. Overview of the Test Procedure
    In accordance with EPCA, DOE is developing test procedures to 
evaluate the energy use associated with the envelope of walk-in coolers 
and freezers. The walk-in envelope includes, but may not be limited to, 
walls, floor, ceiling, seals, windows, and/or doors comprised of single 
or composite materials designed to isolate the interior, refrigerated 
environment from the ambient, external environment. For the purposes of 
developing this test procedure and evaluating potential performance 
standards for walk-in equipment, DOE considers the envelope to also 
include lighting and other energy-consuming components of the walk-in 
that are not part of its refrigeration system (e.g., motors for 
automatic doors, anti-sweat heaters, etc.). DOE is considering the 
following definition for ``envelope,'' which would be inserted into 10 
CFR part 431:
    (1) The portion of a walk-in cooler or walk-in freezer that 
isolates the interior, refrigerated environment from the ambient, 
external environment; and
    (2) All energy-consuming components of the walk-in cooler or walk-
in freezer that are not part of its refrigeration system.
    DOE requests comments on this proposed definition.
    DOE also evaluated several available industry test procedures to 
measure the energy performance of various components of the walk-in 
envelope, but was unable to find a test procedure that would evaluate 
the entire envelope system. Consequently, DOE developed its own 
methodology, including a prescriptive calculation procedure, which 
incorporates specific component tests and allows for an overall energy 
performance value of the envelope to be determined. The proposed test 
measurements and accompanying calculation procedures to ascertain the 
overall energy performance value are described in the following 
sections.
2. Test Methods
    As discussed above, DOE was unable to find a single, existing 
comprehensive test procedure for evaluating walk-in cooler and freezer 
envelopes. However, DOE identified and evaluated many recognized 
industry standards that could be applied to the testing of certain 
components and characteristics of walk-in envelopes. DOE incorporated 
an insulation test and an air infiltration test, with some 
modifications, into the proposed test procedure. The evaluation 
process, the results of the evaluation, and details of the proposed 
test methods are described in the following sections.
a. Insulation
    Insulation comprises a significant component of walk-in units. EPCA 
specifies that ASTM C518-04, ``Standard Test Method for Steady-State 
Thermal Transmission Properties by Means of the Heat Flow Meter 
Apparatus,'' must be used, along with specific foam temperatures for 
freezer or cooler applications specified in EPCA, to determine the R 
value of individual walk-in envelope insulation materials. (42 U.S.C. 
6314(a)(9)(A)) Commenters identified two issues of significance for DOE 
to consider when developing a test procedure for insulation: aging and 
moisture absorption. DOE discusses these issues in the subsections that 
follow.
i. Aging of Foam Insulation
    EPCA requires that the test procedure for walk-ins use an R value 
that shall be the 1/K factor multiplied by the thickness of the panel. 
(42 U.S.C. 6314(a)(9)(A)) The Act does not specify when the R value 
should be calculated, a key issue interested parties raised at the 
framework public meeting. Specifying when the R-value should be 
calculated is a critical consideration because several sources indicate 
that the R-value of certain materials can change over time.
    Craig stated that R values tend to deteriorate over time and that 
different materials exhibit unique rates of deterioration. (Craig, 
Public Meeting Transcript, No. 15 at p. 215 and No. 8 at p. 1) Craig 
expressed concern that using an initial R value (R value as measured 
within two weeks of manufacture) to determine compliance would ignore 
deterioration that occurs in blown foams over time. Craig argued that 
underestimating the energy use of walk-ins would be the likely outcome 
of using initial R-value, that it would be misleading for end-users, 
and that it would be inconsistent with the goals of the EISA 2007 
legislation and the rulemaking process. (Craig, Public Meeting 
Transcript, No.15 at p. 215) A comment submitted jointly by 
representatives of ASAP, ACEEE, and NRDC (hereafter referred to as the 
``Joint Comment'') stated that the test procedures used should account 
for the potential degradation of panel insulation and door seals over 
time. (Joint Comment, No. 21 at p. 2) Craig also recommended that DOE 
develop an accelerated test procedure that represents lifetime energy 
use and can be completed within 6 months. (Craig, No. 8 at p. 1)
    In the context of foam insulation for walk-ins and the building 
industry, long-term thermal resistance (LTTR), described in greater 
detail below, refers to the impact of diffusion on the thermal 
resistance of insulation materials. In other words, the concentration 
of gaseous blowing agents contained in the foam, and which provide the 
foam with much of its insulating value, is reduced by both the 
diffusion of air into the foam and the secondary process of the blowing 
agent diffusing out of the foam. Because air has a significantly lower 
insulating value, the increased ratio of air to blowing agent reduces 
the foam insulation performance (this process is also known as 
``aging''). This diffusion process causes foam to lose insulating 
value, which is represented by its R-value. As a concept, LTTR 
represents the R-value of foam material over its lifetime by describing 
insulating performance changes due to diffusion over time.
    DOE investigated the issue of aging in foam insulation and found 
that it is widely accepted that the material properties of foam 
insulation made with gaseous blowing agents, other than air and 
including HFC-134a, HFC-245fa, HFC-365mfc, cyclopentanes, change over 
time. The amount of degradation can range from roughly 10-35 percent 
within 2 years of manufacture. Because use of ASTM C518-04 reflects the 
properties of a material at the time it is tested, using ASTM C518-04 
to measure the insulating performance of a foam material at the time of 
manufacture would yield a result that differs from that produced by the 
same test conducted at some later point in time. Additionally, research 
has found that the vast majority of diffusion into and out of foam 
materials manufactured with blowing agents other than air occurs within 
the first 5 years of manufacture. Because the rate of diffusion follows 
an exponential curve, the majority occurs within the first year, after 
which the diffusion curve changes very little as it asymptotically 
approaches the equilibrium point.
    DOE found that various methods of ``conditioning'' foam prior to 
measuring its insulating ability with American Society for Testing and 
Materials (ASTM) C518 have been developed in order to test aged 
insulating value, or LTTR. These standards are contained in five foam 
material specifications:
    (1) ASTM C578-09, ``Standard Specification for Rigid, Cellular 
Polystyrene Thermal Insulation;''
    (2) ASTM C591-08a, ``Standard Specification for Unfaced Preformed 
Rigid Cellular Polyisocyanurate Thermal Insulation;''

[[Page 193]]

    (3) ASTM C1029-08, ``Standard Specification for Spray-Applied Rigid 
Cellular Polyurethane Thermal Insulation;''
    (4) ASTM C1126-04, ``Standard Specification for Faced or Unfaced 
Rigid Cellular Phenolic Thermal Insulation;'' and
    (5) ASTM C1289-08, ``Standard Specification for Faced Rigid 
Cellular Polyisocyanurate Thermal Insulation Board.''
    DOE found that since their development in the 1980s, the most 
widely accepted conditioning methods are the 180-day conditioning at 73 
[deg]F or a 90-day conditioning at 140 [deg]F. The goal of the 90-day 
conditioning method was to achieve the same aging result as the 180-day 
method in a shorter period of time. 180-day conditioning is used by 
ASTM C591-08a and ASTM C578-09 and the 90-day condition is typically 
used for ASTM C1089-08 and ASTM C1126-04. By accelerating the 
conditioning, the 90-day test sought to reduce the time and cost 
burdens for manufacturers. Although elevating the temperature of foams 
did achieve a faster rate of aging, subsequent research found that the 
results were not reliable indicators of actual aging because the 
relationship between the diffusion coefficient (a proportionality 
constant that describes the force or rate of diffusion for a given 
substance) and temperature are different for each gas. (Therese 
Stovall, ``Measuring the Impact of Experimental Parameters upon the 
Estimated Thermal Conductivity of Closed-Cell Foam Insulation Subjected 
to an Accelerated Aging Protocol: Two-Year Results,'' p. 1)
    DOE found that efforts to develop an accelerated aging method that 
did not use elevated temperatures resulted in the creation of ASTM 
C1303, which in 1995 introduced the slicing and scaling method, also 
known as the ``thin slicing'' method (a technique used to slice the 
foam so that it ages more rapidly as a function of reduced thickness). 
In contrast to ASTM C578-09, ASTM C591-08a, ASTM C1029-08, ASTM C1126-
04, and ASTM C1289-08, which specify the use of either the 180-day 
conditioning method or 90-day accelerate conditioning method to age the 
foam before measuring its thermal resistance. In contrast, the thin 
slicing method used in ASTM C1303-08 (the most recent version of ASTM 
C1303) was designed specifically to test the aging of foam insulation 
in duration shorter than 180 days, and without the temperature 
elevation methodology used in the 90-day test. (ASTM C1303-08, section 
5.3, at p. 3) By reducing the length of the pathway for diffusion to 
take place, the ``aging'' can be accelerated without the confounding 
effects caused by unique gas properties of the material and blowing 
agent. The results are used to determine the R-value of foam 5 years 
after manufacture, a value that has been shown to correlate strongly 
with the average R-value of foam 15 years after manufacture. (ASTM 
C1303-08, section 5.4, at p. 3)
    In early 2000, the National Research Council Canada and Institute 
for Research in Construction (NRC-IRC) developed CAN/ULC-S770-00. CAN/
ULC-S770-00 incorporated elements of ASTM C1303-95 (the first version 
of ASTM C1303) but altered that standard by clarifying the slicing 
procedure used in ASTM C1303-95, as differing interpretations of the 
previous procedure were thought to be causing variations in the test 
results among third-party testing facilities. These changes sought to 
eliminate inconsistency in the interpretation of the slicing procedure 
and test setup to ensure uniformity across testing labs. In December 
2000, CAN/ULC-S770-00 became the Canadian national mandatory test for 
calculating the LTTR of all foam insulation products (this test has 
since been updated; the most recent version is CAN/ULC-S770-03). 
Members of the U.S.-based Polyisocyanurate Insulation Manufacturers 
Association (PIMA) began to test their products using the same 
procedure on January 1, 2003. The LTTR calculated from this test 
procedure is used for all building insulation product labeling in 
Canada and PIMA products in the United States. Also in 2000, ASTM 
C1303-95 was updated as ASTM C1303-00.
    In a 2005 rule by the U.S. Federal Trade Commission (FTC) in which 
the FTC considered requiring ASTM C1303-00 (the most recent version at 
that time) for product labeling on all foam insulation products, the 
FTC's review process revealed several unresolved issues related to the 
test procedure. (70 FR 31258 (May 31, 2005); 16 CFR Part 460, Labeling 
and Advertising of Home Insulation: Trade Regulation Rule, Final Rule) 
Subsequently, ASTM C1303-00 was updated to address these issues, which 
included foam stack composition, minimum slice thickness and slice 
source, the time between manufacture and test initiation, preparation 
of foam-in-place samples, and other clarifications of the procedure. 
This updated version was published as ASTM C1303-08 and is the most 
recent version of the standard to date.
    Some commenters noted during the framework meeting that the 
application of an impermeable vapor barrier to the surface of the foam 
could reduce the impact of aging. Depending on its end use, foam 
insulation may have facers or skins applied to act as a vapor barrier 
and/or to enhance the bond of construction glues. Kysor stated that 
proper use of skins eliminates aging and the associated reduction of R-
value in polyurethane panels. (Kysor (attachment), No. 29 at p. 1)
    DOE examined this issue and found that foams used in walk-in panels 
are sometimes protected by impermeable barriers designed to prevent 
vapor and/or air exchange into or out of the foam or the interior of 
the walk-in. DOE found research conducted by the National Resource 
Council Canada (NRCC) suggesting that impermeable facers do not 
eliminate aging but may delay the rate of aging and/or the final 
equilibrium of the aged state. (Mukhopadhyaya, P.; Bomberg, M.T.; 
Kumaran, M.K.; Drouin, M.; Lackey, J.; van Reenen, D.; Normandin, N., 
``Long-Term Thermal Resistance of Polyisocyanurate Foam Insulation With 
Impermeable Facers''; Mukhopadhyaya, P.; Bomberg, M.T.; Kumaran, M.K.; 
Drouin, M.; Lackey, J.; van Reenen, D.; Normandin, N., ``Long-Term 
Thermal Resistance of Polyisocyanurate Foam Insulation With Gas 
Barrier''; Mukhopadhyaya, P.; Kumaran, M.K. ``Long-Term Thermal 
Resistance Of Closed-Cell Foam Insulation: Research Update From 
Canada.'') In one of the summary observations of ``Long-Term Thermal 
Resistance of Polyisocyanurate Foam Insulation With Gas Barrier,'' the 
NRCC noted, ``a considerable amount of aging occurred in thin slice 
specimens despite having untouched impermeable facers, as well as a 
glass plate at the bottom of the specimens and edges sealed completely 
with epoxy coating.''
    Additionally, the relationship between the skin and the rate of 
aging in foam depends on preserving the integrity of both the skin 
surface and the bonding between the skin and insulation. Punctures, 
made to allow for the installation of light fixtures, doors, and 
shelving, undermine the integrity of the skin. Walk-in insulation 
panels and their skins also typically separate over time due to 
shrinkage of foam materials after manufacture. While most foam 
materials contract by less than 1 percent of their total volume, 
shrinkage at this level is enough to create significant air gaps. DOE 
found that current methods of conditioning foam materials do not 
account for impermeable facers.
    Finally, like the conditioning standards that are currently in use, 
ASTM C1303-08 is not designed to test impermeably faced foams that may 
be

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used with walk-ins. Significant research has been underway by the NRCC 
but no known test procedure is currently available that accounts for 
the effect of impermeable barriers. DOE requests feedback on this 
issue, including the submission of test results on the impact of 
impermeable skins on long-term R-value. DOE specifically requests that 
interested parties submit or identify peer-reviewed, published data on 
this issue.
    DOE also requests feedback on the use of ASTM C1303-08 with 
impermeably faced foams. DOE may recommend the use of a test procedure 
specifically designed for impermeably faced foam if one is developed.
    As a result of this evaluation, DOE proposes requiring 
manufacturers to use ASTM C1303-08 to determine the LTTR of walk-in 
foam insulation for the purposes of calculating the energy consumption 
of walk-in equipment. DOE requests comments on this proposal.
    DOE is also proposing and seeking comment on the following 
exceptions to ASTM C1303-08:
    (1) Section 6.6.2 of C1303-08 suggests that two standards for 
measuring the thermal resistance may be used. DOE proposes to allow use 
only of ASTM C518-04 (in EPCA, an incorrect form of the date suffix was 
used, e.g., ASTM C518-[20]04), as specified in EPCA. (42 U.S.C. 
6314(a)(9)(A)(ii))
    (2) In section 6.6.2.1, in reference to ASTM C518-04, the mean test 
temperature of the foam during R-value measurement would be -6.7  2 [deg]C (20  4 [deg]F) with a temperature 
difference of 22  2 [deg]C (40  4 [deg]F) for 
freezers and 12.8  2 [deg]C (55  4 [deg]F) with 
a temperature difference of 22  2 [deg]C (40  4 
[deg]F) for coolers. This change replaces the standard mean temperature 
of 75 [deg]F for ASTM C518-04 with the EPCA specified values.
    (3) For the purposes of preparing samples with foam-in-place 
method, section A2 should be followed exactly except for the following 
modifications to accommodate foam-in-place methods that may be used 
during the manufacture of walk-in panels:
     (3.1) Instead of following A2.3, which specifies that the 
foam be sprayed onto a single sheet of wood, the sample shall be foamed 
into a fully closed box of internal dimension 60 cm x 60 cm by desired 
product thickness (2ft x 2ft x Desired thickness). The box shall be 
made of \3/4\ inch plywood and internal surfaces wrapped in 4 to 6 mil 
polyethylene film to prevent the foam from adhering to the box 
material.
     (3.2) Instead of following section A2.4, which specifies 
the spraying of foam layers onto a open sheet of plywood, the cavity 
shall be filled using the manufacturer's typical foam-in-place method 
through a standard injection port or other process typically used to 
foam the product being tested.
     (3.3) In section A2.6, which defines the single surface in 
contact with the board to be the ``surface,'' the definition of the 
foam's ``surface'' shall be the two surface regions in contact with the 
60 x 60 cm sections of the box.
     (3.4) Section A2.8 shall not be followed because the 
prepared sample will not have any ``free rise'' component.
    DOE proposes that manufacturers select foam test thicknesses based 
on design specifications and practice. If a foam's thickness as 
manufactured varies from the tested product thickness, DOE proposes 
that the R-value of that foam at its manufactured thickness may be 
interpolated using the results of ASTM C1303-08, provided that the 
manufactured thickness does not vary from the tested product thickness 
by more than  0.5 inches. For example, if 4-inch and 6-inch 
products were prepared, interpolation between 3.5 and 4.5 inches would 
be allowed for the 4-inch foam and 5.5 and 6.5 inches for the 6-inch 
foam. If the manufacturer determines that final foam thickness should 
be outside of the tested range, then additional testing would be 
necessary to fit the criterion for interpolation. Manufacturers should 
make their sample selections accordingly to avoid the need for 
additional testing. DOE requests feedback on the use of interpolation 
within the specified  0.5 inch range.
    DOE proposes that the results for each of the sample sets of three 
stacks should be reported as specified by ASTM C1303-08. As defined by 
ASTM C1303-08, after thin slices of foam are cut, the slices are 
organized into ``stacks'' of slices to match the original overall 
thickness of the sample. The procedure defines three stack types: (1) 
Stacks comprised of only surface slices of foam, (2) stacks of only 
core slices and (3) a mixture of core and surface slices. A ``surface'' 
slice and a ``core'' slice are defined in ASTM C1303 as ``a thin-slice 
foam specimen that was originally adjacent to the surface of the full-
thickness product and that includes any facing that was adhered to the 
surface of the original full-thickness product'' and ``a thin-slice 
foam specimen that was taken at least 5 mm (0.2 in.) or 25% of the 
product thickness, whichever is greater, away from the surface of the 
full thickness product,'' respectively. The R-value of only the mixed 
stack would be used to calculate the energy p