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[6450-01-P] 

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: Final rule. 

SUMMARY: On January 4, 2010, the U.S. Department of Energy (DOE) issued a notice of 

proposed rulemaking (January 2010 NOPR) to establish new test procedures for walk-in coolers 

and walk-in freezers (WICF or walk-ins). On September 9, 2010, DOE issued a supplemental 

notice of proposed rulemaking (September 2010 SNOPR) to propose changes to the test 

procedures that it proposed in the NOPR. Those proposed rulemakings serve as the basis for 

today’s action. DOE is issuing a final rule that establishes new test procedures for measuring the 

energy efficiency of certain walk-in cooler and walk-in freezer components including panels, 

doors, and refrigeration systems. These test procedures will be mandatory for product testing to 

demonstrate compliance with energy standards that DOE is establishing in a separate, but 
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concurrent rulemaking, and for representations starting 180 days after publication. This final rule 

incorporates by reference industry test procedures that, along with calculations established in the 

rule, can be used to measure the energy consumption or performance characteristics of certain 

components of walk-in coolers and walk-in freezers. Additionally, the final rule clarifies the 

definitions of “Display door,” “Display panel,” “Door,” “Envelope,” “K-factor,” “Panel,” 

“Refrigerated,” “Refrigeration system,” “U-factor,” “Automatic door opener/closer,” “Core 

region,” “Edge region,” “Surface area,” “Rating condition,” and Percent time off” as applicable 

to walk-in coolers and walk-in freezers. 

DATES: The effective date of this rule is [INSERT DATE 30 DAYS AFTER DATE OF 

PUBLICATION IN THE FEDERAL REGISTER]. The final rule changes will be mandatory 

for product testing starting [INSERT DATE 180 DAYS AFTER DATE OF PUBLICATION 

IN THE FEDERAL REGISTER]. 

The incorporation by reference of certain publications listed in this rule was approved by the 

Director of the Federal Register on [INSERT DATE 30 DAYS AFTER DATE OF 

PUBLICATION IN FEDERAL REGISTER]. 

ADDRESSES: The public may review copies of all materials related to this rulemaking 

at the U.S. Department of Energy, Resource Room of the Building Technologies Program, 950 

L’Enfant Plaza, SW., Suite 600, Washington, DC, (202) 586–2945, between 9 a.m. and 4 p.m., 

Monday through Friday, except Federal holidays. Please contact Ms. Brenda Edwards at the 

above telephone number, or by email at Brenda_Edwards@ee.doe.gov, for additional 

information regarding visiting the Resource Room. 
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Docket: The docket is available for review at regulations.gov, including Federal Register 

notices, framework documents, public meeting attendee lists and transcripts, comments, and 

other supporting documents/materials. All documents in the docket are listed in the 

regulations.gov index. However, not all documents listed in the index may be publicly available, 

such as information that is exempt from public disclosure. 

A link to the docket web page can be found at: 

www1.eere.energy.gov/buildings/appliance_standards/commercial/wicf.html. This web page 

will contain a link to the docket for this notice on the regulations.gov site. The regulations.gov 

web page will contain simple instructions on how to access all documents, including public 

comments, in the docket. 

FOR FURTHER INFORMATION CONTACT: 

 Mr. Charles Llenza, U.S. Department of Energy, Office of Energy Efficiency and 

Renewable Energy, Building Technologies Program, EE-2J, 1000 Independence Avenue, SW., 

Washington, DC, 20585-0121. Telephone: (202) 586-2192. E-mail: Charles.Llenza@ee.doe.gov. 

 Mr. Michael Kido, U.S. Department of Energy, Office of the General Counsel, GC-71, 

1000 Independence Avenue, SW., Washington, DC, 20585-0121. Telephone: (202) 586-8145. 

E-mail: Michael.Kido@hq.doe.gov or Ms. Elizabeth Kohl, U.S. Department of Energy, Office of 

the General Counsel, GC-71, 1000 Independence Avenue, SW., Washington, DC, 20585-0121. 

Telephone: (202) 586-7796. E-mail: Elizabeth.Kohl@hq.doe.gov
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SUPPLEMENTARY INFORMATION: 

This final rule incorporates by reference into subpart R of Title 10, Code of Federal Regulations, 

part 431 (10 CFR part 431), the following industry standards: 

 (1) AHRI 1250 (I-P)-2009, “2009 Standard for Performance Rating of Walk-In Coolers and 

Freezers,” approved 2009. 

(2) ASTM C1363-05, “Standard Test Method for Thermal Performance of Building Materials 

and Envelope Assemblies by Means of a Hot Box Apparatus,” approved May 1, 2005. 

 (3) DIN EN 13164:2009-02, “Thermal insulation products for buildings—Factory made 

products of extruded polystyrene foam (XPS)—Specification,” approved February 2009. 

(4) DIN EN 13165:2009-02, “Thermal insulation products for buildings—Factory made rigid 

polyurethane foam (PUR) products—Specification,” approved February 2009. 

(5) NFRC 100-2010[E0A1], “Procedure for Determining Fenestration Product U-factors,” 

approved 2010. 

Copies of ASTM standards can be obtained from ASTM International, 100 Barr Harbor 

Drive, West Conshohocken, PA 19428-2959, (610) 832-9585, or www.astm.org. 
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 Copies of AHRI standards can be obtained from AHRI. Air-Conditioning, Heating and 

Refrigeration Institute, 2111 Wilson Boulevard, Suite 500, Arlington, VA 22201, (703) 600-

0366, or www.ahrinet.org. 

 Copies of DIN EN standards can be obtained from CEN. European Committee for 

Standardization (French: Norme or German: Norm), Avenue Marnix 17, B-1000 Brussels, 

Belgium, Tel: + 32 2 550 08 11, Fax: + 32 2 550 08 19 or www.cen.eu. 

 Copies of NFRC standards can be obtained from NFRC. National Fenestration Rating 

Council, 6305 Ivy Lane, Ste. 140, Greenbelt, MD 20770, (301) 589-1776, or www.nfrc.org. 

You can also view copies of these standards at 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. 

Table of Contents 

I. Authority and Background

II. Summary of the Final Rule

III. Discussion

A. Overall Approach: Component-Based Testing

1. Test Metrics

2. Responsibility for Testing and Compliance

3. Basic Model
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B. Test Procedures for Envelope Components

1. Definition of Envelope

2. Heat Transfer through Panels

3. Energy Use of Doors

4. Heat Transfer via Air Infiltration

5. Electrical Components

C. Test Procedures for Refrigeration Systems

1. Definition of Refrigeration System

2. Refrigeration Test Procedure: AHRI 1250 (I-P)-2009

3. Alternative Efficiency Determination Method

D. Other Issues -- Definition of Walk-In Cooler or Freezer

IV. Procedural Issues and Regulatory Review

A. Review Under Executive Order 12866

B. Review under the Regulatory Flexibility Act

1. Statement of the need for, and objectives of, the rule

2. Summary of the significant issues raised by the public comments, DOE’s response to 

these issues, and any changes made in the proposed rule as a result of such comments

3. Description and Estimated Number of Small Entities Regulated

4. Description and Estimate of Compliance Requirements and Description of Steps to 

Minimize the Economic Impact on Small Entities.

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
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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. Approval of the Office of the Secretary

I. Authority and Background 

 Title III of the Energy Policy and Conservation Act (42 U.S.C. 6291-6317; “EPCA” or, 

“the Act”) sets forth a variety of provisions designed to improve energy efficiency. (All 

references to EPCA refer to the statute as amended through the Energy Independence and 

Security Act of 2007 (EISA 2007), Pub. L. 110-140 (Dec. 19, 2007)). Part C of Title III (42 

U.S.C. 6311–6317), which was subsequently redesignated as Part A-1 for editorial reasons, 

establishes an energy conservation program for certain industrial equipment. This includes walkin coolers and walk-in freezers, the subject of today’s notice. (42 U.S.C. 6311(1), (20), 6313(f), 

and 6314(a)(9)) 

 Under EPCA, this program consists essentially of three parts: (1) testing, (2) labeling, and 

(3) Federal energy conservation standards. The testing requirements consist of test procedures 

that manufacturers of covered products or equipment must use (1) as the basis for certifying 
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compliance with the applicable energy conservation standards adopted under EPCA, and (2) for 

making representations about the efficiency of those products. Similarly, DOE must use these 

test requirements to determine whether the products comply with any relevant standards 

promulgated under EPCA. 

 Section 312 of the Energy Independence and Security Act of 2007 (“EISA 2007”) 

amended EPCA by adding certain equipment to this energy conservation program, including 

walk-in coolers and walk-in freezers (collectively “walk-in equipment,” “walk-ins,” or 

“WICF.”). (42 U.S.C 6311(1), (20), 6313(f), and 6314(a)(9)) As amended by EISA 2007, EPCA 

requires DOE to establish new test procedures to measure the energy use of walk-in coolers and 

walk-in freezers. (42 U.S.C. 6314(a)(9)(B)(i)) The new test procedures for WICF equipment are 

the subject of this rulemaking. EPCA also directs DOE to publish performance-based standards 

and promulgate labeling requirements (42 U.S.C. 6313(f)(4)(A) and 42 U.S.C. 6315(e), 

respectively). These actions will be covered in separate rulemakings. 

In the notice of proposed rulemaking published January 4, 2010 (January 2010 NOPR or, 

in context, NOPR), DOE proposed to establish test procedures to measure the energy efficiency 

of walk-in coolers and freezers. 75 FR 186. DOE identified several issues in its proposal based 

on the public comments submitted in response to the January 2010 NOPR and further research. 

These issues included: (1) the proposed definition of a walk-in cooler or freezer with regards to 

the upper temperature limit; (2) the proposal to create test procedures for the envelope and 

refrigeration system of a walk-in cooler or freezer; (3) the proposal to group walk-in envelopes 

and refrigeration systems with essentially identical construction methods, materials, and 

components into a single basic model; and (4) the proposed calculation methodology for 
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determining the energy consumption of units within the same basic model. 75 FR 186, (Jan. 4, 

2010). On March 1, 2010, DOE held a public meeting to receive comments, data, and 

information on the January 2010 NOPR. Through their comments, interested parties raised 

significant issues and suggested changes to the proposed test procedures. DOE determined that 

some of these comments warranted further consideration and published a supplemental notice of 

proposed rulemaking on September 9, 2010 (September 2010 SNOPR or, in context, SNOPR). 

75 FR 55068. DOE received 22 written comments on the September 2010 SNOPR. This final 

rule addresses comments from the January 2010 NOPR that were not addressed in the September 

2010 SNOPR and comments received on the September 2010 SNOPR. 

 

General Test Procedure Rulemaking Process

 Under 42 U.S.C. 6314, EPCA sets forth the criteria and procedures DOE must follow 

when prescribing or amending test procedures for covered equipment. EPCA provides that test 

procedures “shall be reasonably designed to produce test results which reflect energy efficiency, 

energy use and estimated annual operating costs of a type of industrial equipment (or class 

thereof) during a representative average use cycle as determined by the Secretary [of Energy], 

and shall not be unduly burdensome to conduct.” (42 U.S.C. 6314(a)(2)) 

 

 Additionally, EPCA notes that if the procedure determines estimated annual operating 

costs, the procedure “shall provide that such costs shall be calculated from measurements of 

energy use in a representative average use cycle (as determined by the Secretary), and from 

representative average-unit costs of the energy needed to operate such equipment during such 

cycle.” (42 U.S.C. 63114(a)(3)) Further, the statute provides that DOE “shall provide 
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information to manufacturers of covered equipment respecting representative average unit costs 

of energy.” Id. 

 With respect to today’s rulemaking, the test procedure DOE is prescribing today is a new 

test procedure. Today’s rule establishes a comprehensive testing regime to ensure minimum 

levels of performance by applying the component-based approach detailed in EISA 2007. 

 The separate but concurrent energy conservation standards rulemaking for walk-in coolers and 

walk-in freezers will be based on the performance of walk-in coolers and walk-in freezers as 

measured by the test procedure set forth in this final rule. 

II. Summary of the Final Rule 

 Today’s final rule establishes a new test procedure for measuring the energy efficiency of 

walk-in cooler and walk-in freezer equipment. The test procedure is essentially composed of 

tests for the principal components that make up a walk-in: panels, doors, and refrigeration. 

Testing individual components of walk-in coolers and walk-in freezers is simpler and less 

burdensome to manufacturers than testing an entire walk-in. In this test procedure, DOE also 

provides a method for calculating the energy use of an entire envelope, or the efficiency of a 

refrigeration system, based on the results of the component tests. 

 The test procedure incorporates by reference the industry test procedures ASTM C1363-

05, “Standard Test Method for Thermal Performance of Building Materials and Envelope 

Assemblies by Means of a Hot Box Apparatus,” DIN EN 13164:2009-02, “Thermal insulation 
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products for buildings— Factory made products of extruded polystyrene foam (XPS)—

Specification,” DIN EN 13165:2009-02, “Thermal insulation products for buildings— Factory 

made rigid polyurethane foam (PUR) products—Specification,” NFRC 100-2010[E0A1], 

“Procedure for Determining Fenestration Product U-factors,” and AHRI 1250 (I-P)-2009, “2009 

Standard for Performance Rating of Walk-In Coolers and Freezers.” 

 Concurrently, DOE is undertaking an energy conservation standards rulemaking to 

address the statutory requirement to establish performance standards for walk-in equipment by 

2012. (42 U.S.C. 6313(f)(4)(A)) DOE will use this test procedure in the concurrent process of 

evaluating potential performance standards for the equipment. After the compliance date of the 

performance standards, this walk-in cooler and walk-in freezer test procedure, along with any 

future statistical sampling plans that may be adopted, must be used by manufacturers to 

determine compliance with the standards, and by DOE to ascertain compliance with the 

standards in any enforcement action. Moreover, once any final test procedure is effective, any 

representation of the energy use of walk-in equipment or components must reflect the results of 

testing that equipment using the test procedure. 

III. Discussion 

 In this section, DOE describes the overall approach it followed in developing today’s test 

procedure for walk-in cooler and freezer equipment, including envelope components and 

refrigeration systems. The following section also addresses issues raised by interested parties, 

which consisted of the following entities: 
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• Manufacturers: American Panel, Craig Industries, CrownTonka, Heatcraft Refrigeration 

Products (Heatcraft), Hill Phoenix, International Cold Storage (ICS), Kysor Panel 

Systems (Kysor Panel), Manitowoc, Master-Bilt, Owens Corning, Nor-Lake, 

ThermalRite, Thermo-Kool, and Zero Zone; 

• Material suppliers: Carpenter Company (Carpenter); 

• Trade associations: AHRI, Center for the Polyurethanes Industry (CPI); 

• Utility companies: Pacific Gas & Electric Company (PG&E), Southern California Edison 

(SCE), Sacramento Municipal Utility District (SMUD), and San Diego Gas and Electric 

(SDG&E); 

• Advocacy groups: Appliance Standards Awareness Project (ASAP), Alliance to Save 

Energy (ASE), American Council for an Energy-Efficient Economy (ACEEE), Natural 

Resources Defense Council (NRDC), Northeast Energy Efficiency Partnerships (NEEP), 

and Northwest Energy Efficiency Alliance (NEEA); 

• Other parties: Oak Ridge National Laboratory (ORNL), and the Small Business 

Administration (SBA). 

 

A. Overall Approach: Component-Based Testing

 In the framework document, DOE contemplated developing a single test for an entire 

walk-in cooler or freezer. See 

http://www1.eere.energy.gov/buildings/appliance_standards/commercial/pdfs/wicf_framework_

doc.pdf. However, feedback from interested parties indicated that a single test procedure for the 

entire WICF would not be practical because many walk-ins are assembled on site with 
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components from different manufacturers, which would make on-site testing infeasible. DOE 

then proposed in the January 2010 NOPR and September 2010 SNOPR to develop separate tests 

for the envelope and refrigeration system of a walk-in, which in aggregate would represent the 

performance of the entire walk-in (75 FR 186, 191 (Jan. 4, 2010) and 75 FR 55068, 55070 (Sept. 

9, 2010)). DOE proposed to have one metric for the refrigeration system, which would be an 

efficiency metric, and one metric for the envelope, which would be an energy use metric. The 

envelope metric would account for electrical use of envelope components, as well as any energy 

used by the refrigeration system to reject the heat contributed by conduction, infiltration, and 

other heat sources. In this way, DOE intended to capture the energy impact of components, such 

as panels, that do not themselves consume electricity. 

 DOE received comments on the September 2010 SNOPR from interested parties stating 

that the walk-in cooler and walk-in freezer main components could be further broken down into 

their own constituent components: panels and doors of envelopes and unit coolers and 

condensing units of refrigeration systems. Commenters explained that all of these components 

could be produced by separate manufacturers and then assembled into a complete walk-in. 

Because of this situation, it would be difficult to determine who should test the walk-in envelope, 

the refrigeration system, or both. It would also be difficult to determine who would be best 

positioned to ensure the walk-in cooler or freezer complied with an energy conservation 

standard. DOE acknowledges these and similar concerns from the stakeholders. 

 Based on the information provided by commenters and DOE’s own research, DOE has 

determined that a component-based approach would address the unique challenges posed in 
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regulating the energy efficiency performance of walk-in envelopes. As noted above, these 

challenges include the fact that walk-in units are frequently assembled using components made 

by multiple manufacturers, and walk-in installers may not be equipped to test all the components 

that comprise a walk-in. These factors indicate that a component-based approach would not only 

help ensure compliance with whatever energy conservation standards that DOE sets, but also 

reduce the overall testing burden on the manufacturers, including small businesses who are 

involved in producing walk-in units, either in full or in part. 

Moreover, DOE notes that the adoption of such an approach is consistent with the 

component-based approach that Congress took when it enacted EISA 2007. Thus, DOE is 

adopting a component-level approach for this rule and discusses the specific component metrics 

in greater detail in section III.A.1. 

 

1. Test Metrics 

 As stated previously, DOE initially proposed separate test procedures for envelopes and 

refrigeration systems of walk-ins along with different test metrics for each. The metric for the 

refrigeration system would be an efficiency metric, and the metric for the envelope would be an 

energy use metric that would account for the electrical use of envelope components and the 

energy used by the refrigeration system to reject the heat contributed by conduction, infiltration, 

and other heat sources. To account for different sizes of envelopes, DOE further proposed that 

the result of the envelope test procedure should be a normalized energy use metric—the total 

energy use divided by the external surface area of the envelope (energy use per square foot). 
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 Several interested parties disagreed with the proposed metrics. NEEA stated that 

regulating walk-in coolers and walk-in freezers on the basis of annual energy use would not 

accurately estimate actual energy use, and therefore such estimates would be misleading for 

almost all installed systems. NEEA suggested using an overall U-value for the entire envelope 

and a spreadsheet that calculates the overall U-factor of a walk-in by weighted area. (NEEA, No. 

0061.1 at p. 1 and 9; NEEA, No. 0061.2 at p. 1) (In this and subsequent citations, the document 

number refers to the number of the comment in the Docket for the DOE rulemaking on test 

procedures 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.) NRDC 

also disagreed with the annual energy use metric because of the number of assumptions that 

would be required and the potential to confuse customers. (NRDC, No. 0064.1 at p. 7) NRDC 

further stated that normalizing energy use to the surface area would be unusual and may not be 

useful. (NRDC, No. 0064.1 at p. 2) NEEA suggested that the envelope metric should be a Ufactor (which is a characterization of the heat loss performance). (NEEA, No. 0061.1 at p. 7) A 

comment submitted jointly by SCE, SDG&E, PG&E, and SMUD, hereafter referred to as the 

Joint Utilities, suggested an area-based conductance metric for the envelope that would consider 

both opaque and transparent surfaces. (The Joint Utilities, No. 0059.1 at p. 2) NRDC also 

suggested a metric for refrigeration systems that would encompass the total equivalent warming 

impact and measure the heat loads from refrigeration systems impacting a building’s heating, 

ventilation, and air conditioning (HVAC) system. (NRDC, No. 0064.1 at p. 8) A comment 

submitted jointly by ACEEE, ASAP, ASE, NRDC, NEEP, and NEEA on the September 2010 

SNOPR (hereafter referred to as The Joint SNOPR comment) stated that the energy conservation 
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standard for envelopes should be the overall heat gain (U-overall) with separate standards for 

walk-in coolers and walk-in freezers. (Joint SNOPR Comment, No. 0074.1 at p. 2) 

While other interested parties suggested specific metrics for walk-in components, 

manufacturers also offered suggestions for overall walk-in metrics. Craig Industries 

recommended combining the envelope and refrigeration calculations to calculate the overall 

efficiency of the complete walk-in system and labeling each walk-in with that efficiency metric. 

(Craig, No. 0068.1 at p. 6) Zero Zone stated that the test procedure should include performance 

testing to verify adequate temperatures inside the walk-in. (Zero Zone, No. 0077.1 at p. 1) 

 In view of the component-level approach being adopted today, DOE is not establishing 

an overall energy use metric for the envelope in this test procedure. Instead, DOE is establishing 

separate metrics for the individual components of the walk-in: the wall and ceiling panels 

(hereafter referred to as non-floor panels), floor panels; the display and non-display doors; and 

the refrigeration system. Regarding Zero Zone’s suggestion that the procedure verify that 

adequate internal temperatures are used in evaluating a walk-in unit’s efficiency, DOE does not 

believe that such a requirement is necessary in light of the component-based approach being 

adopted today. 

The panel metric determined by the test procedure accounts for the conductance and is in 

terms of U-factor (that is, the thermal transmittance) measured in Btu/ h-ft2

-

o

F, as NEEA, the 

Joint SNOPR Comment, and the Joint Utilities recommended. The metric for display and nondisplay doors accounts for the thermal transmittance through the door and the electricity use of 
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any electrical components associated with the door, and is in terms of energy use, measured in 

kWh/day. DOE believes that requiring separate metrics for specific individual walk-in 

components does not constitute a substantive change from what was proposed in the September 

2010 SNOPR because this Final Rule only requires tests that were proposed for components in 

the September 2010 SNOPR. Also, the September 2010 SNOPR and this final rule contain 

similar calculation methodologies. 

2. Responsibility for Testing and Compliance 

 DOE proposed to adopt separate tests for the envelope and refrigeration system of a 

walk-in and require the manufacturers of each to test and certify the part they manufacture. 75 

FR 186, 191 (Jan. 4, 2010) and 75 FR 55068, 55070 (Sept. 9, 2010). In response to this proposed 

approach, DOE received multiple comments regarding who should assume testing, certification, 

and compliance responsibilities. The Joint SNOPR Comment recommended that DOE focus on 

factory-produced products (i.e. kits) instead of walk-ins that are assembled on-site from 

components from different manufacturers. (Joint SNOPR Comment, No. 0074.1 at p. 1) The 

Joint SNOPR Comment further suggested that panel, refrigeration system, and door 

manufacturers each be responsible for compliance and certification responsibilities for their own 

products. (Joint SNOPR Comment, No. 0074.1 at pp. 2-3) Thermo-Kool agreed with this 

approach and submitted a copy of a regulatory framework proposed by NEEA, in which 

envelope, door, and refrigeration manufacturers would be responsible for testing and complying 

with the standards for the components they manufacture. (Thermo-Kool, No. 0072.1 at p. 1) 
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DOE received several other comments which it summarized in the certification, 

compliance, and enforcement (CCE) final rule, published on March 7, 2011. 76 FR 12422, 

12444. In brief, some of those comments agreed with the approach suggested by the Joint 

SNOPR Comment and Thermo-Kool that individual component manufacturers should test, 

certify, and ensure compliance of their respective components. Other commenters recommended 

that the manufacturer, the assembler, or the system designer of the overall walk-in should be 

responsible for the compliance of the walk-in with the standards. 76 FR 12442-12446. 

 In the CCE final rule, DOE addressed these comments by defining the manufacturer of a 

walk-in as follows: 

Manufacturer of a walk-in cooler or walk-in freezer means any person who: 

(1) Manufactures a component of a walk-in cooler or walk-in freezer that affects energy 

consumption, including, but not limited to, refrigeration, doors, lights, windows, or walls; 

or 

(2) Manufactures or assembles the complete walk-in cooler or walk-in freezer 

 76 FR 12504. 

 

 The definition extends the compliance responsibility to both the component manufacturer 

and the assembler. In the CCE final rule, DOE clarified that component manufacturers would be 

the entity responsible for certifying compliance of the components they manufacture for walk-in 

applications and ensuring compliance with the applicable Federal standards of those components. 

Assemblers of the complete walk-in system are required to use only components that are 

certified to meet the applicable Federal standards. DOE also adopted a flexible enforcement 
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framework in which it will determine who is responsible for noncompliance on a case-by-case 

basis. 76 FR 12444. 

 

 DOE notes that the provisions and clarifications in the CCE final rule were made in the 

context of component manufacturers certifying their components to the existing standards in 

EPCA, which prescribe requirements on a component-level basis. DOE has decided to continue 

this approach in developing test procedures and performance-based standards for walk-in coolers 

and freezers. DOE believes that, within the very limited context of walk in equipment, EPCA 

created a means for DOE to set performance-based standards for certain walk-in component 

manufacturers. In particular, because Congress set requirements for specific components used in 

walk-in applications, it provided DOE with the implicit authority to set performance-based 

standards at the component level for these specific components. This unique ability stems from 

the manner in which Congress set standards for walk-in equipment by prescribing, among other 

things, specific performance-based requirements for wall, ceiling, door, and floor insulation 

panels used in walk-ins. See 42 U.S.C. 6313(f). 

 Because interested parties, including entities who produce these components and are 

subject to today’s requirements, have indicated to DOE that the energy efficiency performance of 

WICF components would be most readily and easily tested and certified by component 

manufacturers, DOE intends to take this approach for WICF test procedures and performance 

standards. DOE acknowledges the numerous difficulties that commenters have noted with 

alternative proposed approaches. By requiring individual component manufacturers to certify 

that their components satisfy specified performance-based standards, DOE can ease the overall 
20 

burden on walk-in manufacturers relative to the alternatives that were under consideration as part 

of the January 2010 NOPR and September 2010 SNOPR. Therefore, in this test procedure, DOE 

is establishing tests for the components of a walk-in (i.e. panels, doors, and refrigeration 

systems) and anticipates that component manufacturers will test their equipment using the 

applicable procedure and, in the future, will certify that they comply with the appropriate 

standard. DOE emphasizes that until performance standards are established, manufacturers are 

not required to use this test procedure to certify equipment to DOE (although they must use this 

test procedure in making representations as to the performance of their components). However, 

because the prescriptive standards established by the 2007 amendments to EPCA are already in 

effect, manufacturers must demonstrate compliance with them using the method specified in the 

CCE final rule. 76 FR 12422. 

3. Basic Model 

 DOE proposed a definition of basic model for both envelopes and refrigeration systems. 

75 FR 186, 188-189 (Jan. 4, 2010) and 75 FR 55068, 55071-55073 (Sept. 9, 2010). DOE 

received comments from interested parties on the definition and summarized them in the CCE 

final rule. 76 FR 12422. Consistent with its component-level approach to certification, discussed 

in section III.A.2, and taking the comments from interested parties into consideration, DOE 

decided to define a basic model for each of the key components of a walk-in, rather than defining 

a basic model for the entire walk-in. DOE emphasized that although the term “basic model” is 

defined on the component level, it is still implemented in the same manner as it is in the rest of 

DOE’s appliance standards program; that is, a basic model consists of equipment that is 
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essentially the same with respect to energy consumption, efficiency, or other measure of 

performance. 76 FR 12444-12446. 

 DOE provided, in relevant part, the following definition of basic model in the CCE final 

rule: 

Basic model means all components of a given type of walk-in cooler or walk-in freezer 

(or class thereof) manufactured by one manufacturer, having the same primary energy 

source, and which have essentially identical electrical, physical, and functional (or 

hydraulic) characteristics that affect energy consumption, energy efficiency, water 

consumption, or water efficiency; and 

(1) with respect to panels, which do not have any differing features or 

characteristics that affect U-factor. 

* * * 

 76 FR 12504 (providing definition of “basic model” for walk-ins) (to be codified at 10 

CFR § 431.302). 

 DOE believes applying the basic model concept at the component level will reduce the 

testing burden on manufacturers while ensuring that their products meet any applicable standard, 

because it removes the difficulty of testing and/or certifying different sized walk-ins that would 

have different energy consumption levels. 76 FR 12445. The CCE final rule provides that 

manufacturers may elect to group individual models into basic models at their discretion to the 

extent the models have essentially identical characteristics that affect energy efficiency or energy 

consumption. Manufacturers may also rate models conservatively – i.e. the tested performance 
22 

of the model(s) must be at least as good as the certified rating – after applying the appropriate 

sampling plan. 76 FR 12429. The basic model concept is applied slightly differently to panels, 

doors, and refrigeration systems because of their different characteristics. These differences are 

explained below. 

a. Basic Model of Panels 

 Panels are construction components that are not doors and that are used to construct the 

envelope of the walk-in. These components comprise the elements separating the interior 

refrigerated environment of the walk-in from the exterior environment. In this test procedure, 

panels are classified as either floor panels, non-floor panels, or display panels. A display panel is 

a panel that is entirely or partially comprised of glass, a transparent material, or both and is used 

for display purposes. Floor and non-floor panels are mostly comprised of insulating material and 

are not primarily used for display purposes. For all types of panels, the energy efficiency metric 

is the U-factor, which is a measure of conductive, convective, and radiative heat transfer and 

which takes into account composite panel characteristics, which may include the insulation type, 

structural members, any type of transparent material (e.g. glass), and panel thickness. See section 

III.B.2 for details on how the U-factor is determined. DOE considers a panel basic model to 

include panels which do not have any differing features or characteristics that affect the U-factor. 

76 FR 12504. 

DOE notes that manufacturers who make customized panels may experience a higher 

certification burden than manufacturers of standardized panels. For example, under today’s 

procedure, a panel’s U-factor is a surface area-independent metric, which implies that variation 
23 

in panel width and height alone would not be expected to affect the U-factor rating if all other 

characteristics were equal. In those instances where no changes in energy efficiency would 

occur, these panels could be grouped as a basic model. In contrast, smaller floor and non-floor 

panels may have a higher proportion of framing material to non-framing material, or other 

structural members, which could affect the overall panel U-factor rating if the framing material 

or framing geometry has different thermal conductivity performance than the neighboring 

insulation. Therefore, for two or more floor or non-floor panels that are equivalent in materials 

and other characteristics but differ in their frame to insulation proportions such that they have 

different U-factor ratings, the panels would be considered different basic models and would need 

to be certified independently to DOE, if the manufacturer chooses to claim different U-factor 

ratings. However, DOE emphasizes that as explained in section III.3, manufacturers may group 

models into basic models at their discretion as long as the tested performance of the models is at 

least as good as the certified rating. 

DOE has also introduced additional provisions to reduce the testing and certification 

burden on floor and non-floor panel manufacturers. See section III.B.2.a for details. 

As explained above, the energy efficiency metric for display panels is the U-factor, as for 

floor and non-floor panels. However, unlike a floor, ceiling, or wall panel, a display panel is 

essentially a window. Therefore, in this test procedure, DOE is requiring the U-factor of display 

panels to be tested using NFRC 100-2010[E0A1], “Procedure for Determining Fenestration 

Product U-factors,” which DOE proposed in the SNOPR for measuring the U-factor of doors and 

windows, including their framing materials. 75 FR 55083. (Sept. 9, 2010) As with floor and non-
24 

floor panels, the basic model concept allows manufacturers to group display panels that are 

essentially identical in U-factor into one basic model, which DOE anticipates will reduce the 

testing burden on display panel manufacturers. Also, NFRC 100-2010[E0A1] allows verified 

computer models to simulate a display panel’s energy consumption, another factor that reduces 

the manufacturer’s testing burden. 

b. Basic Model of Doors 

 A door is an assembly installed in an opening on an interior or exterior wall that is used 

to allow access or close off the opening and that is movable in a sliding, pivoting, hinged, or 

revolving manner of movement. For walk-in coolers and walk-in freezers, a door includes the 

door panel, glass, framing materials, door plug, mullion, and any other elements that form the 

door or part of its connection to the wall. This test procedure defines two types of doors, display 

and non-display doors. Display doors are doors designed for product movement, display, or both, 

rather than the passage of persons, and non-display doors are considered to be all other types of 

doors. For all doors, the energy consumption metric that DOE is adopting in today’s rule 

incorporates the U-factor and any electrical components built into the door. (See section I.A.1.a 

for details.) Calculating this metric requires the use of NFRC 100-2010[E0A1], “Procedure for 

Determining Fenestration Product U-factors,” which DOE proposed in the SNOPR for 

measuring the U-factor of doors and windows, including their framing materials. 75 FR 55083. 

(Sept. 9, 2010) Applying the NFRC test yields an overall U-factor for the tested door. Then, 

through calculations outlined in Appendix A, the U-factor and the electrical energy consumption 

are combined to create a rating for the door. 
25 

 As with panels, doors with essentially identical energy consumption levels may be 

grouped into a basic model and rated conservatively. 76 FR 12429 and 12504. The basic model 

concept can be used to reduce the testing and certification burdens by allowing manufacturers to 

group doors that are essentially identical in energy consumption but cosmetically different. The 

NFRC procedure also permits either a physical test or a verified computer model to be used 

when determining the U-factor of the door. The latter of these options would be expected to 

reduce testing burden because only a series of calculations would need to be run by an NFRCapproved computer modeling program. DOE also notes that the calculations for energy 

consumption of door components are not based on testing, which reduces the general testing 

burden for doors. Any results from physical tests, computer simulations, and calculations must 

be retained as required by the CCE final rule. 76 FR 12494. 

c. Basic Model of Refrigeration Systems 

 The refrigeration system consists primarily of a compressor, condenser, unit cooler, 

valves, and piping. It is considered a component under the component level approach (see 

section III.A) that DOE is adopting in today’s final rule. As with the panels and doors, and 

consistent with the approach promulgated in the CCE final rule, manufacturers may elect to 

group individual models into basic models at their discretion to the extent the models have 

essentially identical electrical, physical, and functional characteristics that affect energy 

efficiency or energy consumption. Furthermore, manufacturers may rate models conservatively, 

meaning the tested performance of the model(s) must be at least as good as the certified rating, 

after applying the appropriate sampling plan. 76 FR 12429. DOE believes these provisions will 

reduce the burden of testing for refrigeration manufacturers, including those who make 
26 

customized equipment. DOE may also consider methods which allow manufacturers to use an 

alternate method of determining the energy use of the refrigeration system in a future 

rulemaking. This concept is further discussed in section III.C.3. 

B. Test Procedures for Envelope Components

 The envelope consists of the insulated box in which items are stored and refrigerated. In 

the NOPR and SNOPR, DOE proposed methods for evaluating the performance characteristics 

of insulation, testing thermal energy gains related to air infiltration, and determining direct 

electricity use and heat gain due to internal electrical components. The proposed procedure used 

these methods to determine the energy use associated with the envelope by calculating the effect 

of the envelope’s characteristics and components on the energy consumption of the walk-in as a 

whole. Those characteristics and components included 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 impact on the refrigeration 

system energy consumption was determined by calculating the energy consumption of a 

theoretical or “nominal” refrigeration system when paired with the tested envelope. 75 FR 186, 

191 (Jan. 4, 2010) and 75 FR 55068, 55074 (Sept. 9, 2010). 

 As described in section III.A, DOE is no longer requiring manufacturers to determine the 

energy consumption of the entire envelope in this final rule. Rather, DOE is establishing metrics 

for the principal components of the envelope (i.e. the panels and doors) as described in section 
27 

III.A.1. In doing so, DOE is requiring manufacturers to use the same physical tests for the 

components that it proposed in the NOPR and SNOPR, but is introducing revisions to the 

calculations in Appendix A of the new procedure. These revisions will enable manufacturers to 

calculate the required component metrics from the results of those tests. 

 For panels, DOE is adopting separate approaches depending on whether a given panel is 

a display or non-display panel. Display panels are panels that are primarily made of transparent 

material and used for display purposes. Display panels are considered equivalent to windows 

because of their transparent characteristics and associated thermal heat transfer properties, and 

therefore the U-factor will be measured by NFRC 100-2010[E0A1], “Procedure for Determining 

Fenestration Product U-factors,” which DOE proposed in the SNOPR for measuring the U-factor 

of doors and windows, including their framing materials. 75 FR 55083. (Sept. 9, 2010) Nondisplay panels are floor and non-floor panels. Since both floor and non-floor panels are typically 

made out of a composite of insulation, framing, and facer material, both types of panels will be 

tested using the same methodology. In today’s rule, the physical tests pertaining to the 

performance of non-display panels are from ASTM C1363-05, “Standard Test Method for 

Thermal Performance of Building Materials and Envelope Assemblies by Means of a Hot Box 

Apparatus” and, for foams that experience aging, DIN EN 13164:2009-02, “Thermal insulation 

products for buildings—Factory made products of extruded polystyrene foam (XPS)—

Specification” or DIN EN 13165:2009-02, “Thermal insulation products for buildings—Factory 

made rigid polyurethane foam (PUR) products—Specification,” as applicable. These tests were 

proposed in the SNOPR. 75 FR 55068, 55075-55076 and 55081 (Sept. 9, 2010). In this final rule, 
28 

panel performance is denoted by its overall U-factor, or thermal transmittance, which is 

determined by the test procedures and calculation methodologies described in section III.B.2. 

 DOE is requiring one test for door performance, NFRC 100-2010[E0A1], “Procedure for 

Determining Fenestration Product U-factors,” which was proposed in the SNOPR. 75 FR 55083 

(Sept. 9, 2010). This test measures conduction through a door, whether it is a display door or a 

non-display door. The total energy consumption of a door is calculated as the effect of a door’s 

thermal load on the refrigeration system combined with the door’s electrical energy use, as 

described in section 4.5 and section 4.4 of Appendix A of this final rule. The effect on the 

refrigeration system is determined by calculating the energy consumption that a theoretical or 

“nominal” refrigeration system would use to reject the heat that was transmitted through the 

door. The energy that would be used by the theoretical refrigeration system to reject a given 

amount of heat is represented by the energy efficiency ratio (EER) of the refrigeration system. 

The test procedure uses the same nominal refrigeration system EER for all tested doors to enable 

direct comparisons of the performance of walk-in doors across a range of sizes, product classes, 

and features. The nominal EER values for cooler and freezer refrigeration (i.e. 12.4 Btu/W-h and 

6.3 Btu/W-h for coolers and freezers, respectively) are the same as those proposed in the SNOPR 

for calculating the energy use of the envelope. See 75 FR 55013 (Sept. 9, 2010). 

1. Definition of Envelope 

 In the January 2010 NOPR, DOE proposed the following definition of “envelope:” 

Envelope means (1) a piece of equipment that is the portion of a walk-in cooler or walk-
29 

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. 

75 FR 186, 192 (Jan. 4, 2010). 

 The walk-in envelope was proposed to include, but not be limited to, walls, floors, 

ceilings, seals, windows, doors, or any combination thereof, composed of single or composite 

materials. DOE did not propose any changes to this definition in the September 2010 SNOPR. 

 Master-Bilt, BASF, ThermalRite, ACEEE, and ICS submitted written comments 

supporting the proposed definition for the walk-in envelope. (Master-Bilt, No.0027.1 at p. 1; 

BASF, No. 0021.1 at p. 3; ThermalRite, No. 0049.1 at p. 1; ACEEE, No. 0052.1 at p. 2; ICS, No. 

0045.1 at p. 1) However, Nor-Lake asked that the definition of envelope exclude components of 

the envelope purchased separately by the end user to enable the manufacturer of the envelope to 

avoid compliance responsibility for the performance of those components. (Nor-Lake, No. 

0023.1 at p. 2) ICS requested clarification on the preemption of energy codes by building, 

electrical, and mechanical codes and stated that the definition must allow for structural and 

electrical safety code compliance over energy compliance when in conflict. (ICS, No. 0045.1 at 

p. 1) A representative from Gonzaga Law argued that the definition proposed by the DOE was 

too inclusive but did not propose an alternative definition. (Gonzaga Law, No. 0018 at p.1) At 

the public meeting for the January 2010 NOPR, ICS suggested that DOE’s standards and 

definitions should align with NSF’s (formerly known as the National Sanitation Foundation) 

definition of envelope and requirements. (ICS, Public Meeting Transcript, 0016 at p. 30) (In this 
30 

and subsequent citations, “Public Meeting Transcript” refers to the transcript of the March 1, 

2010, public meeting on the proposed test procedures for walk-in coolers and freezers. “No. 

0016” refers to the document number of the transcript in the Docket for the DOE rulemaking on 

test procedures for walk-in coolers and freezers, Docket No. EERE-2008-BT-TP-0014; and the 

page number refers to the place in the transcript where the statement preceding appears.) 

DOE notes the comments and suggestions from Master-Bilt, BASF, ThermalRite, 

ACEEE, ICS, and Gonzaga Law. However, because DOE is taking a component-based 

approach, the proposed envelope definition is no longer applicable for the purpose of this test 

procedure. As suggested by ICS, when evaluating potential standards applicable to walk-ins, 

DOE will also consider their related requirements that manufacturers need to satisfy. In response 

to Nor-Lake’s comment regarding components not supplied by the envelope manufacturer, DOE 

clarifies that each component manufacturer is responsible for testing its component with the 

appropriate test procedure as discussed in section III.A.2. The envelope component manufacturer 

is not responsible for the end user’s implementation of the component; rather, the manufacturer 

would be responsible only for the component’s compliance as designed. Also, the envelope 

assembler is responsible for using WICF-compliant components to assemble the total envelope. 

2. Heat Transfer through Panels 

a. U-Factor of Composite Panels Including Structural Members of Panels 

 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 to 

determine the K-factor of walk-in insulation. The statute defines the R-value as equal to the 
31 

value of 1/K-factor multiplied by the thickness of the panel. (42 U.S.C. 6314 (a)(9)(A)(i)−(ii)) In 

response to the January 2010 NOPR, interested parties commented that the heat conduction 

through structural members must be considered because this factor could affect the conductance 

through the composite walk-in insulation panel. Accordingly, DOE proposed in the September 

2010 SNOPR to use ASTM C1363-05, “Standard Test Method for Thermal Performance of 

Building Materials and Envelope Assemblies by Means of a Hot Box Apparatus,” to measure the 

overall U-factor of fully assembled panels to help account for the impact that structural members 

have on the overall U-factor. 75 FR 55074. 

 Several interested parties -- NEEA, AHRI, Master-Bilt, Thermo-Kool, Carpenter, and 

Bally -- supported the use of ASTM C1363-05 to measure the overall panel U-factor. (NEEA, 

No. 0061.1 at p. 2; AHRI, No. 0070.1 at p. 2; Master-Bilt, No. 0069.1 at p. 1; Thermo-Kool, No. 

0072.1 at p. 1; Carpenter, No. 0070.1 at p.2; Bally, No. 0078.1 at p. 2)) 

 Other interested parties, however, disagreed with DOE’s proposal to use ASTM C1363-

05 to measure panel performance. At least some of these concerns were premised on a mistaken 

belief that DOE’s proposal would result in the elimination of structural members embedded into 

panels. For example, a comment submitted jointly by the manufacturers CrownTonka, 

ThermalRite, and ICS (collectively referred to as the Joint Manufacturers) recommended that 

structural members be excluded from the stated R-value requirements for overall envelope 

thermal resistance. The Joint Manufacturers explained that many walk-ins require the use of 

structural members to comply with building codes and to help support loads placed on the 

building from factors such as snow and wind. The Joint Manufacturers stated that ASTM C518-
32 

04 should be used to measure the K-factor of foam, as specified in EPCA. (42 U.S.C. 6314 

(a)(9)(A)(i)−(ii)) (Joint Manufacturers, No. 0062.1 at p. 1) 

 While American Panel agreed with DOE’s general approach that the R-value of structural 

members should be considered in determining the overall U-factor and submit data to 

demonstrate the impact of structural members on the overall U-factor, it stated that the composite 

panel must meet the minimum R-value requirement. American Panel continued to state that the 

R-value should be calculated by using a weighted percentage of foam R-value and structural Rvalue based on the percentage each material represents in the panel. (American Panel, No. 

0057.1 at p. 1; American Panel, No. 0057.1 at p. 2; American Panel, No. 0057.3 at p. 1) It 

asserted that ASTM C1363-05 is not the appropriate test method for measuring the insulating 

values of foam, and added, along with Craig Industries and Carpenter, that ASTM C518-04 

should be used to measure heat conduction through panels. (American Panel, No. 0057.1 at p. 2; 

Craig, No. 0068.1 at p. 2; Carpenter, No. 0067.1 at p. 2) Craig Industries was concerned that 

using ASTM C1363-05 to calculate the heat conduction through structural members may not 

take the reduction of joints (that is, panel to panel interfacing members) into consideration. Craig 

Industries recommended that the structural members should be tested with a procedure to 

represent the real R-value, which would replace the R-value of the insulation where it is replaced 

with structural members. (Craig, No. 0057.13 at p. 2) Carpenter further asserted that ASTM 

C518-04 is simpler and less costly to perform than C1363-05. (Carpenter, No. 0067.1 at p. 2) 

Thermo-Kool, on the other hand, disagreed with the approach of using R-value testing of 

different components of the composite panel to determine heat loss. (Thermo-Kool, No. 0072.1 

at p. 1) Bally, who agreed with DOE’s proposed approach, requested clarification specifically 
33 

regarding how the two tested areas would be used to represent the performance of a panel. 

(Bally, No. 0078.1 at p. 2) 

 None of the interested parties offered any further explanation for their views other than 

those already described. 

 In this final rule, the terms “foam” and “insulation” are used synonymously, but a panel 

is the fully manufactured product that contains, but is not limited to, the insulating material, 

metal skin, framing material, other structural members, or any combination thereof. To address 

the Joint Manufacturers’ concerns about the potential elimination of structural members, DOE 

emphasizes that the overall U-factor testing required by today’s final rule will not prevent 

manufacturers from including structural members in panels because the existing standards in 

EPCA only regulate the R-value of the foam and do not restrict the overall panel U-factor or the 

R-value of the structural components. The R-value of insulation, which is 1/K-factor as 

determined by ASTM C518-04, will still have to comply with the existing EPCA requirements 

for insulation. (42 U.S.C. 6314 (a)(9)(A)(i)−(ii)) However, the overall U-factor of the fully 

assembled panel, including structural members, may be used to meet an energy conservation 

standard for panels, which will be determined in a parallel rulemaking. Including ASTM C1363-

05 will provide a more accurate means to represent the overall heat transfer performance of 

panels. DOE believes this procedure will be beneficial because it will capture the effects of 

structural members that incorporate insulation or otherwise contribute to the efficiency of the 

walk-in. 
34 

 Additionally, while DOE acknowledges the concerns raised by American Panel, the Joint 

Manufacturers, Craig Industries, and Carpenter, the final rule includes ASTM C1363-05 as part 

of the test procedure in order to determine the overall U-factor of the panel. DOE is including 

this protocol as part of the test procedure because heat conduction through structural members is 

a significant panel characteristic that is not addressed under the statutorily-prescribed testing 

requirements (i.e. ASTM C518-04). While ASTM C518-04 could be used to individually 

measure the R-value of structural members, or any other material, as Craig Industries suggested, 

DOE believes that this approach would be more costly because of the many materials that could 

comprise a panel and the need to test each material separately under that approach. Furthermore, 

DOE believes that panel geometry could make calculations to combine the R-value of each 

material into an overall panel R-value complicated and burdensome. 

 DOE also acknowledges Craig Industries’ concern that ASTM C1363-05 does not 

account for the reduction of joints (that is, panel to panel interfacing members). Since DOE is 

adopting an approach to ensure the energy efficiency performance of particular components, an 

approach suggested by numerous commenters, and is no longer considering the effects of 

infiltration, panel joint issues are outside of this approach. 

 DOE notes that American Panel supported the inclusion of structural members in 

calculating the overall U-factor. Furthermore, DOE would like to clarify the calculation 

methodology to address the comment from Bally. Today’s final rule adopts a weighted 

percentage of the panel edge (which may contain structural members) and panel core region 

(which may also include structural members) in order to calculate the panel’s total U-factor. 
35 

DOE believes that using the weighted percentage of edge U-factor and core U-factor to calculate 

the total U-factor will help reduce the manufacturer’s testing burden. 

 In applying this weighted percentage approach, today’s final rule provides that for floor 

or non-floor panels of the same thickness, construction methods, and materials, manufacturers 

must test a pair of 4 ft. by 8 ft. “test panels” to obtain a core U-factor and an edge U-factor. The 

manufacturer must then calculate the overall U-factor of other floor or non-floor panels with the 

same panel thickness, construction methods, and materials using the U-factor results for the core 

and edge region “test panels.” For example, a manufacturer tests a 4 ft. by 8 ft. test panel and 

finds the edge region and core region U-factors. The same manufacturer also produces 6 ft. by 8 

ft. panels that have identical core and edge region thickness, construction methods and materials. 

Therefore, the manufacturer may apply the core and edge region factors to the 6 ft. by 8 ft. panel 

to calculate the overall U-factor of the 6 ft. by 8 ft. panel instead of performing an additional test. 

DOE notes that any calculations that support the certified ratings must be retained along with the 

test data for the “test panels” for all basic models pursuant to the requirements for the 

maintenance of records promulgated in the CCE final rule. 76 FR 12494. DOE expects that, 

based on the information it has collected, including information made available by manufacturers 

on their websites and submitted comments, most manufacturers use the same panel thickness, 

materials, and construction methods for many of their panels, which results in a minimal testing 

burden. 

 In regard to American Panel’s comment that the composite panel must meet the 

minimum R-value requirement, DOE clarifies that EPCA states that only the insulation material 
36 

(that is, the foam) must meet the prescribed R-value. (42 U.S.C. 6313(f)(1)(C)) The test 

procedure is prescribing ASTM C1363-05 as a method of measuring the overall U-factor of the 

entire panel. For EPCA compliance, the R-value of the insulation must be separately determined 

in accordance with ASTM C518-04 as specified in EPCA. (42 U.S.C. 6313(f)(1)(C)) 

 Finally, interested parties suggested changes to the test methodology DOE proposed. 

NRDC stated that irregular or non-homogeneous foam products should be tested for actual Rvalue where there is no quality control to maintain the orientation of the foam in the finished 

product. To clarify, DOE believes that when NRDC noted the concern about the orientation of 

the foam, they were referring to bun-stock foam products. Bun-stock products are manufactured 

in “buns” that may have foam cell structure similar to the grains in wood. Like wood, depending 

on how the buns are cut into boards, the orientation of the cell “grains” may vary by finished 

board. NRDC continued to suggest that if a foam product cannot be tested, then the stated Rvalue should be a conservative number representing the lowest R-value for a tested material. 

(NRDC, No. 0064.1 at p. 4) NRDC also suggested that DOE review the impact of testing the 

final fabricated panel rather than requiring manufacturers to specially construct units for testing, 

because specially constructed units may not represent the typical product (NRDC, No. 0064.1 at 

p. 4) Master-Bilt suggested changing the width and length of the panel to 8 x 4 ft. +/- 1 ft. to 

have more tolerance and allow for the testing of standard width panels. (Master-Bilt, No.0069.1 

at p.2) 

 In response to NRDC’s comment about irregular or non-homogeneous foam products, 

DOE anticipates that the prescribed sampling procedures for certification will accurately capture 
37 

the foam’s R-value. A sampling plan is intended to ensure accurate and statistically repeatable 

results are achieved when using the test procedure. DOE notes NRDC’s concern that specifically 

constructed units may not represent an actual product. However, in order to reduce the testing 

burden presented by ASTM C1365-05, DOE is maintaining the approach of specifying two test 

regions of a pair of representative panels. At one test region, the tester measures the U-factor of 

the perimeter that may contain structural members and panel-to-panel interface area (the “Panel 

Edge”), while at the other region the tester measures the U-factor of the core area of the panel 

(the “Panel Core”) which may also contain structural members. The U-factor for each region is 

then applied to panels of the same type (that is, same foam type, framing material, and panel 

thickness) to obtain an overall U-factor that is representative of actual products sold by the panel 

manufacturer. DOE applies a calculation methodology to extrapolate the core and edge U-factor 

to determine the U-factor of any panel produced by a manufacturer. 

 In response to Master-Bilt’s comment, DOE agrees that increasing the tolerance of the 8 

ft x 4 ft test panel to +/- 1 ft will provide manufacturers with a greater range of standard sized 

panels. DOE conducted a mathematical analysis to determine how changing the tolerance would 

affect the U-factor as determined by ASTM C1363-05. DOE found that increasing the size 

tolerance of the test panel results in less than a 0.5 percent change to the U-factor as determined 

by ASTM C1363-05. Therefore, DOE has amended the standard size of a test panel for ASTM 

C1363-05 to be 8 ft x 4 ft +/- 1 ft. 
38 

b. Long-Term Thermal Resistance 

 In the January 2010 NOPR and September 2010 SNOPR, DOE cited several studies that 

conclude that lateral gas diffusion, which causes a reduction in R-value, occurs in impermeably 

faced foams. See 75 FR 192-194 and 75 FR 55075-55079. These types of foams are common to 

walk-ins. The lateral gas diffusion occurs over time and affects the energy efficiency 

performance of the foam as diffusion continues. To account for this aging effect on a foam’s 

insulation performance -- and, by extension, the energy consumption of a walk-in due to thermal 

losses attributable to this reduced performance -- DOE, consistent with its proposed approach, is 

adopting a method to account for this phenomenon in walk-in applications. Hill Phoenix added 

that different methods of manufacturing panels should be taken into account when determining 

the test procedure. (Hill Phoenix, No. 0063.1 at p. 2) 

 The most significant factor affecting the efficiency of a walk-in panel is the insulating 

foam in a panel, and accurately capturing the foam’s R-value is critical to measuring the overall 

performance of the panel. Panels can be in use for 10 to 20 or more years before they are 

replaced. Performance metrics for a panel based on initial foam R-value will tend to 

overestimate the amount of energy saved over this equipment’s lifetime. Research on panel aging 

has shown that a 5-year aged R-value found by LTTR testing is representative of the panel’s 

insulation performance over its lifetime, and there are industry tests for walk-in foam that 

estimate the aged R-value over time. Using these industry-developed protocols will enable 

manufacturers to more accurately capture the lifetime performance of a walk-in panel. 
39 

 Incorporating a long term thermal resistance degradation factor improves the reliability of 

test results for walk-in panels. While EPCA contains standards for the R-value or insulating 

performance of the foam, these standards do not specify when the insulating foam must be 

tested. (42 U.S.C. 6313(f)(1)(C)) Variables that impact the time at which panels are tested 

include shipping time, production time, shipment of completed panels to test lab, and test facility 

availability. Changing any one of these variables could result in significantly different test results 

and measured R-values. This is in contrast to most other types of equipment within the appliance 

standards program, which would not exhibit significant differences in performance based on the 

length of time between manufacture and testing. Because of the unique aging profile of certain 

foam types, the timing of a walk-in panel test would affect both manufacturers’ certification of 

the panel U-factors and any enforcement testing undertaken by DOE. Therefore, using LTTR 

values to measure foam performance eliminates the “time” variable that could affect whether a 

panel is shown to comply with an overall performance standard that DOE may set. The purpose 

of the LTTR testing is to accelerate foam aging to the point where the R-value changes relatively 

slowly over time and to then measure its performance, thus improving the repeatability of the test 

because the timing of the test is no longer critical. 

 

In the January 2010 NOPR, DOE proposed to use ASTM C1303-08, “Standard Test 

Method for Predicting Long-Term Thermal Resistance of Closed-Cell Foam Insulation,” to 

calculate the long-term thermal resistance (LTTR) of walk-in foam insulation. 75 FR 186, 

193−94 (Jan. 4, 2010). In the September 2010 SNOPR, DOE proposed to use the updated 

version of ASTM C1303-08, which was ASTM C1303-10. 75 FR 55068, 55075 (Sept. 9, 2010). 

In that notice, DOE also offered an alternative method, Annex C of either DIN EN 13164:2009-
40 

02, “Thermal insulation products for buildings— Factory made products of extruded polystyrene 

foam (XPS)—Specification” or DIN EN 13165:2009-02, “Thermal insulation products for 

buildings—Factory made rigid polyurethane foam (PUR) products—Specification,” as 

applicable, to test for the LTTR. This alternative was offered in response to concerns raised in 

response to the NOPR. The SNOPR requested comments on both of these alternative methods. 

75 FR 55079 (Sept. 9, 2010). 

In light of the comments that DOE received on all of these various testing methods, 

which are addressed below, DOE has decided to adopt DIN EN 13165:2009-02 or DIN EN 

13164:2009-02, as applicable, as the test procedure for determining LTTR. The LTTR value 

determined by DIN EN 13165:2009-02 or DIN EN 13164:2009-02 will be used to determine a 

degradation factor, which will be the LTTR R-value divided by the initial R-value of the foam. 

The initial R-value will be determined in accordance with ASTM C518-04 as specified in the 

EISA 2007 amendments to EPCA and used to establish compliance with those statutorilyprescribed requirements. (42 U.S.C. 6313(f)(1)(C)) The degradation factor is applied to the Ufactor of the panel found by ASTM C1365-05; see section 4.2 and 4.3 in Appendix A. These 

protocols are preferable to ASTM C1303-10 because they account for the effect of impermeable 

facers, which ASTM C1303-10 does not. 

 In response to this approach, DOE received a number of comments. Thermo-Kool noted 

the general need to consider LTTR. It also suggested that the potential for thermal degradation is 

more likely to occur at the panel joints than from actual polyurethane (i.e. foam) issues. 

(Thermo-Kool, 0072.1 at p. 1) The Joint Manufacturers recommended that structural members 
41 

be considered in the long-term thermal resistance performance of any panels with structural 

edges because they may lessen or slow off-gassing over time. (The Joint Manufacturers, No. 

0062.1 at p.1). 

American Panel and Bally opposed DOE’s inclusion of a test procedure that measured 

LTTR. (American Panel, No. 0057.2 at p.1; Bally, No. 0078.1 at p. 2) American Panel explained 

that impermeable or metal skins protect the polyurethane foam from aging and that little change 

will occur in the long term R-value. In support of its claim that impermeably faced metal skins 

protect foam from aging, American Panel submitted the results of a study conducted by 

Carpenter. That study found a 3.6 percent loss in insulating value of a panel after 9 years in a 

walk-in application. (American Panel, No. 0057.2 at p.1) American Panel also asserted that none 

of its customers complained about R-value loss in the panels that American Panel sold to them. 

(American Panel, No. 0057.1 at p. 2) 

 One interested party recommended that DOE collect test data before prescribing a 

particular test method. Bally stated that more data from actual walk-in panels with intact metal 

skins and sealed edges should be collected before DOE includes a test procedure for long-term 

thermal resistance. (Bally, No. 0078.1 at p. 2) 

 DOE acknowledges Thermo-Kool’s assertion that most aging occurs at the panel joints 

and Bally’s suggestion that DOE collect more data to support long term thermal aging. DOE 

notes, however, that polyurethane itself has the potential to age significantly. DOE cited multiple 

studies, in both the January 2010 NOPR and September 2010 SNOPR, that conclude that aging 
42 

occurs in most types of foams commonly used in walk-in applications, including polyurethane. 

75 FR 192-194 (Jan. 4, 2010) and 75 FR 55075-55079 (Sept. 9, 2010). In response to the Joint 

Manufacturers’ comment about accounting for the effect structural members have on LTTR, 

DOE also notes that no known test procedures are available that address edge sealing at this time 

but that this factor could be considered in a future rulemaking. 

 DOE also considered the merits of the submissions in support of American Panel’s 

contention that impermeably faced foams do not undergo significant aging. After evaluating this 

information, however, DOE continues to believe that the inclusion of LTTR testing in the test 

procedure is necessary to accurately measure the R-value of foam. DOE notes that the samples in 

the Carpenter study cited by American Panel were taken from the center of the panel. As DOE 

noted in the SNOPR, another study (the Ottens study, “Industrial Experiences with CO2 Blown 

Polyurethane Foams in the Manufacture of Metal Faced Sandwich Panels”) found that core 

samples do not represent the overall aging of foam in panels because most aging occurs at the 

panel’s perimeter. 75 FR 55068, 55077 (Sept. 9, 2010) (citing Ottens et al., “Industrial 

Experiences with CO2 Blown Polyurethane Foams in the Manufacture of Metal Faced Sandwich 

Panels,” Polyurethane World, 1997.) As a result, the data from this study indicate that the 

Carpenter study’s results do not necessarily provide an accurate portrayal of the likely effects of 

panel aging. 

 Additionally, while American Panel asserted that the lack of customer complaints about 

R-value loss in panels indicates that the deterioration of LTTR values is insignificant, the lack of 

customer complaints may be influenced by a variety of factors. For example, a panel is normally 
43 

only replaced when visibly damaged. However, a panel may have reduced thermal performance 

without any accompanying visual cues suggesting problems with the panel. Accordingly, DOE 

does not believe that the statements and materials cited by American Panel support the premise 

that LTTR of foam is negligible for walk-in panels. 

 Interested parties also made comments on the specific test methods that DOE proposed. 

DOE received some comments from interested parties in favor of using ASTM C1303-10 to 

determine the LTTR of foam insulation. Owens Corning agreed that DOE should use the most 

current version of whichever ASTM standards it planned to use. (Owens Corning, No. 0058.1 at 

p. 1) Craig Industries agreed with the use of ATSM C1303-10, but stated that DOE should 

evaluate if ASTM C1303-10 is appropriate for all present and future foam insulation products. 

(Craig, No. 0068.1 at p. 4) NRDC supported testing insulated products to determine whether the 

R-value degraded over time, and stated that the proposed ASTM standard is acceptable and 

known in the industry. (NRDC, No. 0064.1 at p. 4) NEEA stated that although some interested 

parties have concerns about LTTR values derived from ASTM C1303-10, NEEA believed that 

carefully specifying the physical characteristics of the tested panel samples will address their 

concerns. (NEEA, No. 0061.1 at p.2) 

 Some interested parties disapproved of ASTM C1303-10. American Panel, Hill Phoenix, 

Thermo-Kool, and the Joint Manufacturers opposed using ASTM C1303-10 as the test procedure 

to measure LTTR. (American Panel, No. 0057.1 at p. 2; Hill Phoenix, No. 0063.1 at p. 2; 

Thermo-Kool, 0072.1 at p. 1; the Joint Manufacturers, No. 0062.1 at p. 1) American Panel 

asserted that any testing to determine R-value must allow the foamed-in-place polyurethane to 
44 

remain encapsulated by the metal facers to resemble the real-world application. (American Panel, 

No. 0057.1 at p. 2) Hill Phoenix and Thermo-Kool did not recommend the use of ASTM C1303-

10 because, as noted in section 1.3 of ASTM C1303-10, the standard does not apply to 

impermeably faced foams; therefore, applying the results from ASTM C1303-10 to impermeably 

faced foams would be misleading. Hill Phoenix also suggested that ASTM C1303-10 would 

significantly overestimate foam aging of foamed-in-place polyurethane panels. (Hill Phoenix, 

No. 0063.1 at p. 2) The Joint Manufacturers opposed the use of ASTM C1303-10 for measuring 

long-term R-value decline because it is not intended for use with faced panels and unfairly 

penalizes foamed-in-place polyurethane that has minimal or zero exposure of permeable surfaces 

(the Joint Manufacturers, No. 0062.1 at p. 1) Owens Corning stated that the prescriptive and 

research methods of ASTM C1303-10 are not comparable and will not generate comparable 

results. It added that the Canadian test procedure CAN/ULC S770, which is based on various 

versions of ASTM C1303, has a positive bias and may over-predict foam aging, and submitted 

foam aging data and an article about the CAN/ULC S770 test to support this comment. (Owens 

Corning, No. 0058.1 at p. 2; Owens Corning, No. 0058.1 at p. 1; Owens Corning, No.0058.5 at 

p.19; Owens Corning, No. 0058.2 at p.2) 

Carpenter and Master-Bilt also opposed the use of ASTM C1303-10 for LTTR testing 

and suggested possible alternatives. Carpenter suggested testing initial and aged K-factors per 

ASTM C518 at 20 °F and 55 °F for freezers and coolers, respectively. (Carpenter, No. 0067.1 at 

p. 3) Carpenter stated that ASTM C1303-10 would underestimate the LTTR of impermeably 

faced panels and that LTTR tests should be performed on samples with intact facers. (Carpenter, 

No. 0067.1 at p. 2) Similarly, Master-Bilt explained that panel edges are not 100 percent 
45 

exposed, but are tight against one another and sealed with caulk and vinyl gaskets. Collectively, 

the caulk and gaskets significantly reduce gas migration, thus reducing the effects of aging. 

Therefore, in its view, the testing of skinned panels with exposed edges still considerably 

overstates the insulation degradation. Master-Bilt suggested that a formula based on test data 

from actual walk-in panels that have been installed could be used instead of ASTM C1303-10. 

(Master-Bilt, No. 0068.1 at p.2) 

 DOE agrees with the assessment that ASTM C1303-10 is not adequate for testing 

impermeably faced foams. DOE believes that the concerns about ASTM C1303-10 expressed by 

American Panel, Hill Phoenix, Thermo-Kool, Master-Bilt, the Joint Manufacturers, Carpenter, 

and Owens Corning are addressed by DIN EN 13165:2009-02 and DIN EN 13164:2009-02, 

which account for impermeably faced foams, reduce the testing burden, and are appropriate for 

different types of foam. DIN EN 13165:2009-02 and DIN EN 13164:2009-02 partially rely on a 

formula based on test data, as suggested by Master-Bilt. DOE agrees with Owens Corning that 

the prescriptive and research methods of ASTM C1303-10 are not comparable, and notes that 

DIN EN 13165:2009-02 and DIN EN 13164:2009-02 do not have this problem. 

 One interested party expressed concerns about two of the studies DOE referenced in the 

September 2010 SNOPR. One study was the Ottens study, in which an experiment was 

completed on polyurethane foamed-in-place panels to assess their long-term insulating behavior. 

75 FR 55068, 55077 (Sept. 9, 2010). (Ottens et al., “Industrial Experiences with CO2 Blown 

Polyurethane Foams in the Manufacture of Metal Faced Sandwich Panels,” Polyurethane World., 

1997.) In the SNOPR, DOE estimated that the test was likely representative of panels aged for at 
46 

least 5 years. 75 FR at 55077 (Sept. 9, 2010). ORNL challenged this estimate and stated that the 

results from the Ottens study cannot be correlated to a particular aging period. (ORNL, No. 

0060.1 at p. 2) 

The second study DOE referenced was a round robin test using CAN/ULC-S770-03, a 

standard with the same test methodology as a previous version of ASTM C1303. DOE 

referenced the test to address concerns raised by various interested parties that the thin slicing 

method, CAN/ULC-S770-03. Results from the round-robin study predicted that polyurethane 

would perform at a lower level than extruded polystyrene or even at a level as low as expanded 

polystyrene. 75 FR 55079 (Sept. 9, 2010). ORNL stated the testing used in the referenced study 

relied on the original version of S770, which has been shown to over-predict thermal resistance. 

ORNL added that the test was performed on foams created with blowing agents that are no 

longer used, and the results are not representative of current products. (ORNL, 0060.1 at p. 2) 

Regarding ORNL’s comment about the Ottens study, DOE agrees that the method in the 

study cannot be accurately correlated to a particular aging period. However, in DOE’s view, the 

conclusions reached in those studies illustrate that impermeably faced foams are subject to aging. 

DOE agrees with ORNL’s evaluation of the flaws in the round robin test data but notes that the 

same test was used on each type of foam evaluated, which permits a comparison of the results 

from each type of tested foam. DOE used the results of the round robin test to demonstrate that 

there were no performance differences between polyurethane and polystyrene foams -- not to 

predict the level of thermal resistance over time. 
47 

 Interested parties also commented on the specific testing conditions for ASTM C1303-10. 

ORNL proposed that, if adopted, ASTM C1303-10 should be modified to allow the user to take 

multiple 12 inch × 12 inch specimens from the 48 inch × 96 inch panel, at least 12 inches away 

from the edge of the 48 inch × 96 inch source. (ORNL, No. 0060.1 at p. 2) ORNL suggested 

specifying the aging conditioning temperatures for foam insulation. ORNL explained that while 

most insulation foams must follow aging condition requirements, the conditions used to age bun 

stock foam, which is used in producing foam insulation, may be freely modified. This situation 

could lead to skewed comparisons between products. (ORNL, No. 0060.1 at p. 2) 

Manufacturers also offered views regarding these proposed testing conditions. Craig 

Industries, Carpenter, and Owens Corning stated that the procedures detailed in ASTM C1303-

10 should be conducted at the specified EPCA mean temperatures 55 °F and 20 °F for a cooler 

and freezer, respectively. (Craig Industries, 0068.1 at p. 4; Carpenter, No. 0067.1 at p.3; Owens 

Corning, No. 0058.1 at p. 2) Carpenter also suggested modifying DOE’s proposal by adding a 

provision for molding test panels using unprimed aluminum facers. (Carpenter, No. 0067.1 at 

p.3) NRDC asserted that the proposed temperatures for testing insulation needed to be 

substantiated. (NRDC, 0064.1 at p. 4) Craig Industries asserted that the modifications to ASTM 

C1303-10 proposed by DOE in the September 2010 SNOPR test were acceptable, but wanted 

DOE to ensure that the changes would also apply to expanded polystyrene insulation. (Craig 

Industries, No. 0068.1 at p. 4) Bally suggested that the initial panel size should be changed to 

48 inches ± 3 inches and 96 inches ± 2 inches so that a standard panel configuration could be 

used for the test panel. Bally stated that manufacturers could incur significant costs from 

manufacturing test panels. (Bally, No. 0078.1 at p.2) 
48 

 While DOE appreciates ORNL’s and Bally’s suggested improvements to ASTM C1303-

10, these recommendations are no longer relevant since DOE has decided to adopt DIN EN 

13165:2009-02 and DIN EN 13164:2009-02, which collectively address some of the 

shortcomings of ASTM C1303-10. For example, DIN EN 13165:2009-02 and DIN EN 

13164:2009-02 provide for inclusion of metal facers, while ASTM C1303-10 does not. In regard 

to Bally’s concern about the size of the test panel, a test panel is no longer required to be a 

certain size as long as the panel is large enough for the test sample to be cut from its geometric 

center, as prescribed in Appendix A. Additionally, given the comments from Craig Industries, 

Carpenter, Owens Corning, and NRDC about the temperature conditions for testing, DOE has 

decided to adopt the EPCA mean temperatures of 55 °F and 20 °F for a cooler and freezer, 

respectively for the DIN EN 13165:2009-09 and DIN EN 13164:2009-02 testing conditions. This 

means that when a manufacturer tests a panel for LTTR, the manufacturer will determine the 

initial and aged R-value as specified by DIN EN 13165:2009-09 and DIN EN 13164:2009-02 

except the panel will be rated at 55 °F and 20 °F for a cooler and freezer, respectively. By 

deviating from the temperature condition specified in DIN EN 13165:2009-09 and DIN EN 

13164:2009-02, the fixed increment values and safety increment values will be slightly more 

conservative than the values that would be expected if the LTTR test were performed at the 

temperature condition specified in DIN EN 13165:2009-09 and DIN EN 13164:2009-02, when 

applied to freezer panels. 

In response to Craig Industries’ comment that whatever method is adopted should be 

applicable to expanded polystyrene foam, DOE notes that the foam aging procedures it proposed 
49 

are only applicable to foams that rely on low conductivity blowing agents that are intended to 

stay within the foam for the life of the product. Because it is DOE’s understanding that expanded 

polystyrene foam is not blown with low conductivity blowing agents that are intended to remain 

in the product for its usable life and does not exhibit long term changes in thermal resistance, 

these tests would not apply, nor would they be needed to assess the long term thermal resistance 

of this type of foam. 

One commenter did not agree with the proposed use of any of the protocols. ThermoKool disagreed with both ASTM C1303-10 and DIN EN 13165:2009-02 and DIN EN 

13164:2009-02 because none of these protocols, in its view, is designated for testing composite 

panels faced with metal skins. (Thermo-Kool, 0072.1 at p. 1) DOE agrees with Thermo-Kool 

that ASTM C1303-10 was not designed to test panels with metal facers. However, DIN EN 

13165:2009-02 and DIN EN 13164:2009-02 were designed to account for metal facers on foam. 

DIN EN 13165:2009-02 and DIN EN 13164:2009-02 allow all metal skins or facers to remain on 

the foam during aging and testing. See, e.g., DIN EN 13165:2009-02, Annex C (instructing in 

relevant part to “select a product sample including any product facing.”). 

 

 DOE notes that many of the interested parties that opposed using ASTM C1303-10 to 

measure LTTR supported using DIN EN 13165:2009-02 and DIN EN 13164:2009-02 instead. 

Carpenter agreed with using DIN EN 13165:2009-02 and DIN EN 13164:2009-02 as an 

alternative to ASTM C1303-10. (Carpenter, No. 0067.1 at p. 2) Hill Phoenix and AHRI 

requested more time to review the European test procedure, but Hill Phoenix’s initial assessment 

was that DIN EN 13165:2009-02 was a better option than ASTM C1303-10. (Hill Phoenix, No. 
50 

0063.1 at p. 2; AHRI, No. 0070.1 at p.2) Hill Phoenix added that DOE should adopt test 

procedures that are appropriate for the insulation materials that could be found in walk-in panels, 

which DOE interprets to mean that Hill Phoenix is suggesting that DOE adopt both DIN EN 

13165:2009-02 and DIN EN 13164:2009-02 if DOE uses these standards instead of ASTM 

C1303-10. (Hill Phoenix, No. 0063.1 at p. 2) Master-Bilt also stated DIN EN 13165:2009-02 and 

DIN EN 13164:2009-02 seemed to better account for long-term degradation of foam 

performance, though they acknowledged they did not fully understand DIN EN 13165:2009-02 

and DIN EN 13164:2009-02. (Master-Bilt, No. 0069.1 at p. 2) 

 Other stakeholders had reservations about DIN EN 13165:2009-02 and DIN EN 

13164:2009-02. Craig Industries stated that the alternatives to ASTM C1303-10 may ignore the 

fact that different plastic foam product insulations in the marketplace respond differently to heat. 

(Craig Industries, No. 0068.1 at p. 4) It added that DOE should prevent foamed-in-place walk-in 

manufacturers from picking the most efficient part of the panel for testing. (Craig, No. 0068.1 at 

p. 4) Owens Corning noted that DIN EN 13165:2009-02 and DIN EN 13164:2009-02 appeared 

to be material standards and not test methods, and Owens Corning asked for clarification on what 

the test method would be. (Owens Corning, 0058.1 at p.1) NRDC suggested that DOE review the 

proposed standards, ASTM C1303-10, DIN EN 13165:2009-02, and DIN EN 13164:2009-02, to 

determine which standard yields better results, and what the related testing burden would be to 

adopt a foreign standard. (NRDC, No. 0064.1 at p. 4) 

 DOE notes Carpenter’s, Hill Phoenix’s, AHRI’s, and Master-Bilt’s approval of DIN EN 

13165:2009-02 and DIN EN 13164:2009-02, and in light of the criticisms that DOE has received 
51 

about ASTM C1303-10 and the support for DIN EN 13165:2009-02 and DIN EN 13164:2009-

02, DOE has decided to adopt DIN EN 13165:2009-02 and DIN EN 13164:2009-02 as the test 

procedure for determining LTTR of polyurethane products and extruded polystyrene products, 

respectively (polyisocyanurate products are covered by the test for polyurethane products). 

Today’s final rule provides that the LTTR value determined by Annex C of DIN EN 

13165:2009-02 or DIN EN 13164:2009-02 shall be used to determine a degradation factor. The 

degradation factor will be the LTTR R-value divided by the original R-value of the foam. The 

original R-value of the foam will be tested with ASTM C518-04, as specified by the EISA 2007 

amendments to EPCA, and can be used for compliance with the relevant R-value requirement 

established by those amendments. (42 U.S.C. 6313(f)(1)(C)) The degradation factor is applied to 

the U-factor of the panel found by ASTM C1365-05; see section 4.2 and 4.3 in Appendix A. 

 In response to Owens Corning’s comment that DIN EN 13165:2009-02 and DIN EN 

13164:2009-02 appeared to be material standards and not test methods, DOE notes that Annex C 

of both DIN EN 13165:2009-02 and DIN EN 13164:2009-02 provide the methodology for 

testing. DOE also notes Craig Industries’ concern about using heat to test for LTTR and NRDC’s 

recommendation that DOE compare the different standards that were proposed; however, DOE 

believes DIN EN 13165:2009-02 and DIN EN 13164:2009-02 are more accurate and appropriate 

for assessing the long-term performance of impermeably faced foams used in walk-in coolers 

and freezers because they permit panels to be tested with their facers, and accounts for 

impermeably faced foam. Also, to address Craig Industries’ concern about manufacturers not all 

choosing the same part of the panel, DOE is requiring that this test sample should be taken from 

the geometric center of the test specimen. 
52 

 DOE is largely incorporating DIN EN 13165:2009-02 and DIN EN 13164:2009-02 

except for the requirement that the thermal resistance measurement is conducted at a mean 

temperature of 10 °C. DOE has decided to adopt the EPCA mean temperatures of 55 °F and 20 

°F for a cooler and freezer, respectively for the DIN EN 13165:2009-09 and DIN EN 

13164:2009-02 testing conditions. However, the manufacturer will still have to follow any 

applicable aging conditions prescribed by DIN EN 13165:2009-09 and DIN EN 13164:2009-02. 

By deviating from the temperature condition specified in DIN EN 13165:2009-09 and DIN EN 

13164:2009-02, the fixed increment values and safety increment values will be slightly more 

conservative than the values that would be expected if the LTTR test were performed at the 

temperature condition specified in DIN EN 13165:2009-09 and DIN EN 13164:2009-02, when 

applied to freezer panels. 

c. Moisture Absorption 

 In the January 2010 NOPR, DOE discussed the possibility of testing the impact of 

moisture absorption on the R-value of different insulation materials, evaluated various tests 

developed by ASTM, and reviewed a research paper completed by the U.S. Army Corps of 

Engineers’ Cold Regions Research and Engineering Laboratory (CRREL), which Owens 

Corning submitted to the docket. (Owens Corning, No. 0054.3 at p. 1) DOE initially concluded 

that testing the effect of moisture absorption on the R-value of insulation foam would be 

complex, costly, and time-consuming, and that there was no well-accepted testing method. As a 

result, DOE proposed that the impact of water absorption on R-value not be included in the test 

procedure. 75 FR 186, 194 (Jan. 4, 2010). 
53 

DOE received many comments from interested parties that supported the inclusion of 

some means to account for the effect of water infiltration. At the NOPR public meeting, and in 

several written comments, Craig Industries urged DOE to test for and include the impact of 

moisture absorption in foam. (Craig Industries, Public Meeting Transcript, No. 0016 at p. 248; 

Craig Industries, No. 0035.1 at p. 3; Craig Industries, No. 0068.1 at p. 5; Craig Industries, No. 

0057.13 at p. 5) ACEEE also stated that it was imperative to include the effect of moisture 

absorption. (ACEE, No. 0052.1 at p. 2) Kysor maintained that moisture did not affect the Rvalue of poured-in-place polyurethane, but laminated panels would be severely affected by water 

because of the water-based glue used to bond the insulation to the metal skins. (Kysor, No. 

0053.1 at p. 3) 

Some interested parties suggested possible tests and studies that could be used to measure 

the effect of water absorption. For example, Craig Industries and Owens Corning referred to the 

CRREL study for information about the performance of various materials with water. (Craig 

Industries, No. 0054.1 at p. 2; Owens Corning, Public Meeting Transcript, No. 0016 at p. 250) 

Nor-Lake suggested that an adequate test for water absorption would be ASTM D2842-06, 

“Standard Test Method for Water Absorption of Rigid Cellular Plastics.” (Nor-Lake, No. 0047.1 

at p. 3) Owens Corning suggested that ASTM E96, “Standard Test Methods for Water Vapor 

Transmission of Materials,” could be used to test water vapor permeability rates and determine 

the effect of moisture absorption on foam. (Owens Corning, Public Meeting Transcript, No. 0016 

at p. 253; Owens Corning, No. 0048.1 at p. 1; Owens Corning, No. 0032.1 at p. 3) Owens 

Corning also suggested that ASTM E96 could be used to identify suitable materials for walk-in 
54 

cooler and walk-in freezer applications. (Owens Corning, No. 0048.1 at p. 1 and No. 0032.1 at p. 

3) 

Additionally, joint comments filed by SCE, SMUD, SDG&E, and SCG on the January 

2010 NOPR, hereafter referred to as the Joint Comment, added that although ASTM E96 

produces a conservatively low estimate of moisture permeance at high vapor pressures, DOE 

should evaluate whether using ASTM E96 is better than not accounting for the effect of moisture 

on insulating foam. (Joint Comment, No. 0037.1 at p. 11) The Joint Comment added that there 

may be difficulties in testing and characterizing R-value deterioration in foams due to moisture 

absorption, but DOE should still consider a requirement for testing vapor permeability. (Joint 

Comment, No. 0037.1 at p. 1) Owens Corning also stated that, since DOE raised the proposed 

relative humidity assumption for the test condition from 45 percent to 75 percent in the 

September 2010 SNOPR, DOE implicitly acknowledged the high humidity conditions present in 

walk-in cooler and freezer environments, which, in its view, supported the consideration of the 

impact of moisture on the thermal performance of a walk-in over its lifetime. (Owens Corning, 

No. 0058.1 at p. 2) ACEEE suggested that because a major threat to moisture control for panels 

is the integrity of the exterior skin, a minimally intrusive method to determine the impact of 

moisture absorption would be to assess the vapor diffusion integrity of the sealed panel. 

(ACEEE, No. 0052.1 at p. 2) 

 Other interested parties did not support including water absorption in the test procedure. 

ThermalRite stated that moisture infiltration was unlikely to occur in properly constructed 

panels, water infiltration would most likely be the result of improper materials or manufacturing, 
55 

and that moisture infiltration should be considered inconsequential and removed from proposed 

test procedures. (ThermalRite, No. 0045.1 at p.1; ThermalRite, No. 0045.1 at p. 2; ThermalRite, 

No. 0049.1 at p.2) ICS commented that water infiltration is related to panel installation and that 

there were no data to support that moisture infiltration is caused by the walk-in’s manufacture or 

design. (ICS, Public Meeting Transcript, No. 0016 at p. 253; ICS, No. 0045.1 at p. 1) ICS went 

on to state that, under actual and average usage conditions, water absorption in foam is negligible 

and it recommended that the impact of moisture absorption should be removed from the 

proposed test procedure. (ICS, No. 0045.1 at p. 1; ICS, No. 0045.1 at p. 2) Hill Phoenix 

commented that moisture absorption was not an issue and any moisture issues were generally 

reported by the walk-in cooler or walk-in freezer user and were quickly repaired. (Hill Phoenix, 

No. 0041.1 at p. 2) Carpenter agreed with DOE that the impact of water absorption of foam 

would be difficult to study and quantify, and added that polyurethane foam has an inherently low 

permeability, which would minimize water absorption. (Carpenter, No. 0043.1 at p. 2) TAFCO 

concurred that moisture infiltration into polyurethane foam is not an issue, and that it would not 

cause the R-value to degrade significantly over time. (TAFCO, No. 0040.1 at p. 2) TAFCO also 

stated that they have installed panels in high-humidity environments and they did not encounter 

any cases of water absorption by panels. It urged that DOE not pursue this issue further. 

(TAFCO, No. 0040.1 at p. 2) 

 DOE understands that interested parties have concerns regarding the potential impact of 

moisture absorption on the thermal performance of insulating material over the lifetime of a 

walk-in cooler or freezer. Prior to the publication of the January 2010 NOPR, DOE reviewed 

several methods for testing vapor permeance and water absorption in foam insulation materials. 
56 

However, this review of various test methods showed that there were disparities among the 

different methods, and that there was no general agreement upon a single approach. 75 FR 186, 

194 (Jan. 4, 2010). Moreover, while these tests are designed to measure the performance of 

insulating foam by itself, they would not account for the many unique construction methods and 

combinations of materials employed by manufacturers of panels to minimize moisture 

infiltration. 

At this time, test procedures for measuring the impact of water on foam R-value are not 

yet recognized by a national organization such as ASTM. DOE notes that because of the absence 

of any nationally recognized testing standards, it would need to develop such a protocol. To this 

end, one of DOE’s national labs is in the process of developing procedures to evaluate the impact 

of moisture on insulation R-values. Accordingly, because of the potential ambiguities that are 

currently present with respect to the means by which to assess the impact of moisture absorption 

on the thermal performance of insulating material over time, DOE is not incorporating a method 

to account for moisture absorption at this time. DOE may, however, consider adopting such a 

procedure in the future. 

d. Display Panels 

 In the September 2010 SNOPR, DOE proposed that glass walls (“display panels”) would 

be tested using NFRC 100-2001-E0A to measure their thermal transmittance, or U-factor. 75 FR 

55068, 55098 (Sept. 9, 2010). Display panels are typically found on beer caves and share many 

characteristics with display doors. Notably, they are readily tested or simulated using the 

procedure in NFRC 100-2001-E0A. DOE received no comments regarding its proposed 
57 

approach for display panels. Consequently, DOE is including this test procedure (to be codified 

in section 4.1 of Appendix A) to measure the thermal transmittance of display panels or walls. 

Additionally, to improve clarity, DOE is defining “display panels” as a panel that is entirely or 

partially comprised of glass, a transparent material, or both and is used for display purposes. 

e. Open Areas of Walk-Ins 

 The test procedure DOE is establishing today contains tests for components of walk-ins 

that separate the interior refrigerated environment of the walk-in from the exterior. Zero Zone 

stated that the test procedure should include a method to determine the energy use for walk-ins 

that have open areas to display food. (Zero Zone, No. 0077.1 at p. 1) Because an open area does 

not, by definition, separate the interior refrigerated environment of the walk-in from the exterior, 

an open area is not a component of the walk-in that is covered under this test procedure. 

Accordingly, DOE is not adopting Zero Zone’s suggestion. 

3. Energy Use of Doors 

a. U-Factor of Doors 

 In the September 2010 SNOPR, DOE proposed to rate the total thermal transmittance 

(i.e. U-factor) of doors, including their framing materials or complete door plug, using the test 

procedure NFRC 100-2010[E0A1], “Procedure for Determining Fenestration Product U-factors.” 

75 FR 55068, 55083 (Sept. 9, 2010). DOE specified internal and external rating conditions for 

the test procedure to closely match conditions that would be experienced by the door when it is 

part of a walk-in. 
58 

 NEEA strongly supported DOE’s use of NFRC 100-2010[E0A1] procedures for testing 

the performance of walk-in cooler and freezer doors. (NEEA, No. 0061.1 at p. 2) NRDC agreed 

with DOE’s use of NFRC 100-2010[E0A1] for rating doors with the proposed changes to the 

temperatures used for the testing procedure. (NRDC, No. 0064.1 at p. 6) 

 DOE notes NEEA’s and NRDC’s support and has incorporated the use of NFRC 100-

2001-E0A1 in this final rule. DOE also notes that none of the interested parties submitted 

comments that disagreed with using NFRC 100-2001-E0A1. The thermal transmittance result 

from NFRC 100-2001-E0A1 is then used to calculate the corresponding energy consumption of a 

refrigeration system whose efficiency is given in sections 4.4 and 4.5 of Appendix A for display 

and non-display doors, respectively. This energy metric is combined with the electricity 

consumption from electrical door components to calculate the door’s total energy consumption. 

b. Electrical Components of Doors 

 As described in section III.A.1, the test metric for doors includes the energy consumed by 

electrical components associated with a walk-in door. The electricity consumed by the door will 

be the sum of the rated power associated with each electricity consuming device multiplied by 

the assumed time the device will be operational. Percent time off (PTO) assumptions are given in 

sections 4.4.2 and 4.5.2 of Appendix A for display and non-display doors, respectively. PTO 

assumptions are specified for some electrical components, such as anti-sweat heater wire. For 

any electricity consuming devices for which a PTO is not specified in Appendix A, today’s final 

rule provides that if a manufacturer can demonstrate that the device is controlled by a 

preinstalled timer, control system or other auto-shut-off system, the PTO is assumed to be 25 
59 

percent. For example, if a door has a thermometer mounted on it that consumes electricity, but 

the thermometer has a built in timer so that it shuts off at certain times, then the manufacturer of 

the door can use the PTO value of 25 percent when calculating the energy consumption of the 

thermometer. 

 The test procedure also provides a means for measuring the heat generation of door 

electrical components that are located on the inside surface of the door. This heat is added to the 

heat transmitted through the door and the corresponding refrigeration energy use is calculated 

using the method described in section III.B.3.c. The refrigeration energy use is added to the 

electrical energy use to calculate the total energy consumption of the door. 

 DOE received a comment challenging its assumptions about heat from electrical devices. 

Zero Zone disagreed with the assumption that all anti-condensate heat contributes to the walk-in 

heat load, and instead suggested that 50 to 75 percent of the anti-condensate heat going into the 

display case would be a more appropriate assumption. (Zero Zone, No. 0077.1 at p. 2) After 

further analysis, DOE agrees with Zero Zone’s observation that not all anti-condensate heat 

necessarily contributes to the walk-in heat load because the anti-condensate heat is applied to the 

transparent surface of the display case. Because one side of the transparent surface is in contact 

with the surrounding external environment, a portion of the heat is transmitted from the display 

case to the surrounding environment. Therefore, DOE has revised the equations in sections 4.4.2 

and 4.5.2 of Appendix A to capture only 75 percent of the power from anti-sweat heaters as an 

additional compressor load. 
60 

c. Energy Efficiency Ratio 

 In the January 2010 NOPR, DOE proposed to require that manufacturers measure the 

energy use of walk-in cooler and walk-in freezer envelopes in kWh/day. However, most metrics 

used to describe heat transfer losses are in units of British thermal units (Btu) per unit time. In 

order to convert the thermal energy transmission calculation (Btu/hr) into a measure of electrical 

energy consumed by the refrigeration equipment, DOE proposed to use an energy efficiency 

ratio based on a nominal efficiency of an assumed refrigeration system. The EER values 

proposed for coolers and freezers were 12.4 Btu/W-h and 6.3 Btu/W-h respectively. The values 

were selected to provide a means of comparison and were not intended to represent the actual 

efficiency of the refrigeration system with which the envelope would ultimately be paired. 75 FR 

186, 197 (Jan. 4, 2010). Although the test procedure no longer requires one to calculate the 

overall envelope energy, the concept is still relevant for calculating door energy. 

 DOE received comments in response to the January 2010 NOPR regarding the use of an 

EER value, the assumptions used to calculate the EER value, and the proposed EER values for 

coolers and freezers. BASF commented that the proposed EER assumptions were reasonable. 

(BASF, No. 0021.1 at p. 4) Nor-Lake agreed with DOE’s use of a nominal EER value to convert 

the thermal energy transmission to electrical energy consumption. (Nor-Lake, No. 0047.1 at p. 5) 

Master-Bilt also agreed with the proposed use of a nominal EER but stated that the proposed 

EER values are not achievable. (Master-Bilt, No. 0027.1 at p. 2) Kason requested that the 

nominal EER values be reassessed to represent real world values. (Kason, No. 0055.1 at p. 4) 

Nor-Lake commented that the EER values on their refrigeration models did not match DOE’s 

proposed nominal values. (Nor-Lake, 0023.1 at p. 4) 
61 

 DOE considered these comments and, in conjunction with the supportive comments from 

Master-Bilt, Nor-Lake, and BASF, continues to use an EER value to relate the thermal energy 

transmission to the electrical energy consumed for doors. Despite the comments from Kason, 

Master-Bilt, and Nor-Lake, DOE finds 12.4 Btu/W-h and 6.3 Btu/W-h to be appropriate 

conversions for walk-in coolers and walk-in freezers, respectively, because these EER values 

correspond to nominal EER values contained in the refrigeration test procedure for unit coolers 

connected to multiplex condensing systems (AHRI 1250 (I-P)-2009). DOE is aware that the 

nominal values for this configuration may not represent all walk-ins, but notes that these EER 

values are intended to provide a means of comparison and not directly reflect a real walk-in 

installation. In particular, these EER assumptions are not intended to represent the expected 

efficiency of any particular refrigeration system produced by a manufacturer and are provided as 

a method to converting thermal energy to electrical energy consumed by a refrigeration system. 

4. Heat Transfer via Air Infiltration 

In the January 2010 NOPR, DOE stated that, compared with other energy consumption 

factors such as conduction losses through insulation, air infiltration may be the largest 

contributing factor to envelope thermal load. That notice identified two infiltration pathways: 

steady state leakage and air losses due to door-opening events. To address this issue, DOE 

proposed to include test procedures to measure the steady state infiltration and infiltration from 

door opening events and subsequently modified these test procedures in response to comments to 

the September 2010 SNOPR. See 75 FR 196−197 (Jan. 4, 2010) and 75 FR 55084−55086 (Sept. 

9, 2010). Interested parties submitted comments pertaining to the topic of envelope infiltration, 
62 

including steady state infiltration, door opening infiltration, calculations, and empirical 

methodologies for quantifying the effects of infiltration. 

a. Steady State Infiltration 

 In the January 2010 NOPR, DOE proposed that steady state infiltration of fully 

assembled envelopes must be tested using the method described in ASTM E741-06, “Standard 

Test Method for Determining Air Change in a Single Zone by Means of a Tracer Gas Dilution.” 

75 FR 196 (Jan. 4, 2010). 

 Some interested parties stated that steady state infiltration should not be included in the 

test procedure. Hill Phoenix maintained that an insufficient amount of infiltration would occur in 

a properly installed walk-in, essentially suggesting that DOE abandon the inclusion of infiltration 

in the test. (Hill Phoenix, No. 0063.1 at p. 2) AHRI concurred, stating that a steady-state 

infiltration test is not necessary due to the insignificant amount of infiltration present in a walkin... (AHRI, No. 0070.1 at p. 3) Master-Bilt agreed, suggesting that testing steady-state 

infiltration is unnecessary because this infiltration is insignificant compared with infiltration 

from door openings. (Master-Bilt, No. 0069.1 at p. 2) NRDC suggested that DOE confirm the 

assumption that the impact of infiltration and exfiltration through the envelope is minimal 

compared to the infiltration through the doors, and suggested that DOE should weigh each 

impact. (NRDC, No. 0064.1 at p. 6) 

 Other interested parties commented on the specific test methods DOE proposed in the 

January 2010 NOPR for measuring steady-state infiltration of walk-in envelopes. TAFCO stated 
63 

that ASTM E741-06, Standard Test Method for Determining Air Change in a Single Zone by 

Means of a Tracer Gas Dilution, is an acceptable method for determining steady state air 

infiltration. (TAFCO, No. 0040.1 at p. 3) ACEEE also agreed with using ASTM E741-06. 

(ACEEE, 0052.1 at p. 3) NEEA commented that either ASTM E741-06 or a standard blower test 

is a reasonable method of calculating steady state infiltration, but noted that the blower test 

would be faster and less costly to administer. Therefore, NEEA recommended that DOE test 

ASTM E741-06 and the standard blower door test before prescribing which methodology must 

be used. (NEEA, No. 0061.1 at p. 2) Kysor, on the other hand, stated that it is neither necessary 

nor cost effective to assemble an entire walk-in to test for air infiltration. Kysor stated that each 

component should be tested separately and recommended that DOE use ASTM E1424-08, 

Standard Test Method for Determining the Rate of Air Leakage Through Exterior Windows, 

Curtain Walls, and Doors Under Specified Pressure and Temperature Differences Across the 

Specimen, and ASTM E2357-05, Standard Test Method for Determining Air Leakage of Air 

Barrier Assemblies, because either can test any assembly that will become part of a walk-in. 

(Kysor, No. 0053.1 at p. 3) 

 In the January 2010 NOPR, DOE proposed that ASTM E741-06 should be used to 

measure infiltration; however, in the September SNOPR, DOE determined that ASTM E741-06 

could present an undue burden for manufacturers with respect to the many door combinations 

that are possible. Therefore, DOE proposed in its September 2010 SNOPR to also consider 

measuring steady state infiltration through doors using NFRC 400-2010-E0A1, “Procedure for 

Determining Fenestration Product Air Leakage.” 75 FR 55068, 55084 (Sept. 9, 2010). 
64 

 Interested parties commented on NFRC 400-2010-E0A1 and suggested alternatives. 

NRDC agreed with using NFRC 400-2010-E0A1 to determine infiltration of individual envelope 

components, but also recommended using a pressurization test to determine infiltration of fully 

assembled envelopes, based on ASTM D6670, “Standard Practice for Full-Scale Chamber 

Determination of Volatile Organic Emissions from Indoor Materials/Products.” (NRDC, No. 

2.3.008 at p. 6) AHRI recommended that infiltration could be estimated for a family of doors by 

using a scaling methodology based on a limited number of tests. AHRI cautioned DOE against 

requiring the manufacturer to test every single door because it would be burdensome. (AHRI, 

No. 2.3.015 at p.3) Some interested parties commented on the prescribed testing conditions to be 

implemented with NFRC 400-2010-E0A1. American Panel stated that the proposed steady state 

infiltration test unit is not representative of the average walk-in size and suggested a more 

representative size of 8 feet by 12 feet by 8 feet high. (American Panel, No. 2.3.001 at p. 3) 

American Panel, NEEA, and Bally concurred with DOE’s assumption of 75 percent relative 

humidity, which DOE proposed as a condition of testing. (American Panel, No. 2.3.001 at p. 3; 

NEEA, No. 2.3.005 at p. 5; Bally, No. 0078.1 at p.2) 

DOE notes the specific comments and suggestions from TAFCO, NEEA, ACEEE, 

Kysor, NRDC, AHRI, and American Panel, but has decided not to include steady state 

infiltration in the WICF test procedure at this time. In response to NRDC’s suggestion that DOE 

weigh the impact of steady-state infiltration against other sources of infiltration, DOE believes 

that the contribution of steady state infiltration towards the aggregate energy consumption of a 

well-constructed factory-built walk-in unit is most likely negligible compared to other energy 

consumption pathways for current WICF designs. Higher steady-state infiltration across the 
65 

envelope for site-assembled walk-in coolers and freezers appears to be generally caused by poor 

installation and construction practices. As such, DOE is not incorporating an overall infiltration 

measurement, which is a factor that relies heavily on on-site assembly practices rather than the 

performance of individual components. Given that today’s final rule includes a means to assess 

the performance of specific individual components, the performance of these components will be 

captured under the new procedure and should be sufficiently adequate prior to their installation 

as part of a completed walk-in unit. Should this prove not to be the case, DOE may re-examine 

the procedure and consider modifications to address its potential shortcomings. 

b. Door Opening Infiltration 

 In the January 2010 NOPR, DOE proposed to calculate air infiltration associated with 

each door-opening event using established analytical methods based on equations and 

computational values published in the ASHRAE Refrigeration Handbook. DOE also made 

several assumptions in the test procedure that could have a significant impact on the predicted air 

exchange. The assumptions with the most impact were the number of doorway passages (the 

number of door-opening cycles for a given door), door open-close time, and the amount of time 

the door is held or propped open. 75 FR 186, 196 (Jan. 4, 2010). In the September 2010 SNOPR, 

DOE did not propose to change the basic methodology, but modified some of the assumptions in 

order to differentiate door types. 75 FR 55068, 55085 (Sept. 9, 2010). 

 Some interested parties supported the proposed method. Hired Hand agreed with the 

methodology used for calculating the air infiltration from door openings. (Hired Hand, Public 

Meeting Transcript, No. 0016 at p. 309) Hired Hand emphasized that air infiltration may be the 
66 

largest contributing factor to envelope energy losses. (Hired Hand, Public Meeting Transcript, 

No. 0016 at p. 28; Hired Hand, Public Meeting Transcript, No. 0016 at p. 279; Hired Hand, 

Public Meeting Transcript, No. 0016 at p. 285) American Panel suggested the use of ASHRAE 

values for heat load as the best way to account for the effects of air infiltration. (American Panel, 

No. 0042.1 at p. 2) ThermalRite, Nor-Lake, and Master-Bilt agreed with American Panel’s 

suggestion. (ThermalRite, No. 0049.1 at p. 2; Nor-Lake, No. 0047.1 at p.4; Master-Bilt, Public 

Meeting Transcript, No. 0016 at p. 311) Master-Bilt and Zero Zone also agreed with DOE’s 

assumptions regarding infiltration attributed to door openings. (Master-Bilt, No. 0069.1 at p. 2; 

Zero Zone, No. 0077.1 at p. 2) 

 Other interested parties questioned the applicability of the method to walk-in cooler and 

freezer doors, or questioned DOE’s assumptions in calculating door opening infiltration. Schott 

Gemtron contended that ASHRAE equations may be based on supermarket display cases, 

implying that they may not be applicable to some walk-in doors. (Schott Gemtron, Public 

Meeting Transcript, No. 0016 at p. 314) Hired Hand was concerned that the proposed test 

procedures do not account for the effect of fast-acting doors on air infiltration. (Hired Hand, 

Public Meeting Transcript, No. 0016 at p. 286) SCE and Hired Hand both stated that the 

parameters used to calculate air infiltration should clearly show the benefit of fast-acting doors. 

(SCE, Public Meeting Transcript, No. 0016 at p. 320; Hired Hand, Public Meeting Transcript, 

No. 0016 at p. 320) Hired Hand also recommended that the equations used to calculate air 

infiltration should be based on the operational time the doors are opened over an assumed 24-

hour day. (Hired Hand, No. 0051.1 at p. 4) Zero Zone stated that any air infiltration calculations 

should include additional air infiltration if the evaporator is discharging air in the direction of the 
67 

display doors. (Zero Zone, No. 0077.1 at p. 1) Bally stated that hybrid walk-ins, that is, walk-ins 

sited within another walk-in, should be given beneficial consideration. Bally explained that a 

walk-in freezer sited inside a walk-in cooler would experience less infiltration because of the 

smaller temperature differential between the interior and exterior of the freezer. (Bally, No. 

0078.1 at p.2) 

 Interested parties also made specific comments on the effect of infiltration reduction 

devices (IRDs). ACEEE and ThermalRite supported the infiltration device effectiveness test 

methodology. (ACEEE, No. 0052.1 at p. 3; ThermalRite, No. 0049.1 at p. 2) TAFCO also stated 

that ASTM E741-06 is an acceptable method for determining IRD effectiveness. (TAFCO, No. 

0040.1 at p. 3) NRDC stated that the proposed door opening infiltration calculation from 

ASHRAE Fundamentals 2009 is acceptable for conventional doors, but when doorways are 

protected by an air curtain or other infiltration reduction device, calculations should include the 

effect of such devices on energy use. (NRDC, No. 0064.1 at p. 6) 

 Master-Bilt commented that air infiltration from door openings cannot be modeled in a 

meaningful way and should be excluded from the test methodology. (Master-Bilt, No. 0027.1 at 

p. 2) Hill Phoenix noted that the panel manufacturer has no bearing on door opening frequency, 

which accounts for the majority of the infiltration. (Hill Phoenix, No. 0063.1 at p. 2) NEEA 

suggested that DOE should not make assumptions about the nature of the use of a particular 

walk-in. (NEEA, No. 0061.1 at p. 5) Instead, it recommended that DOE include a prescriptive 

requirement for infiltration reduction devices. (NEEA, No. 0061.1 at p. 5) 
68 

DOE has decided not to include any test procedure for door opening infiltration following 

its decision to have component-level test procedures and standards. Door infiltration is primarily 

reduced by incorporating a separate infiltration reduction device at the assembly stage of the 

complete walk-in. Based on DOE’s understanding of the door manufacturing industry, a typical 

door manufacturer has very few direct means for reducing the door infiltration on its own since 

IRDs are generally designed and manufactured independently from doors and they require proper 

field installation to achieve rated performance. Consequently, at this time, DOE is not 

incorporating provisions that would require measuring the effectiveness of the infiltration 

reduction devices and door infiltration, as suggested by Master-Bilt, Hill Phoenix, and NEEA. 

Likewise, reduction of door infiltration due to the location of the walk-in is not captured, as 

suggested by Bally. 

 

In response to NEEA’s comment recommending a prescriptive standard, DOE notes that 

EPCA has already established a prescriptive requirement for infiltration reduction devices, and 

there may be limited if any benefit to DOE adding additional prescriptive standards for 

infiltration reduction devices. (42 U.S.C. 6313(f)(1)(B)) Nevertheless, DOE will consider the 

need for these types of standards within the context of its ongoing energy standards rulemaking. 

5. Electrical Components 

 In the January 2010 NOPR, DOE proposed to calculate the energy consumption of 

electrical devices using their nameplate rating and duty cycle assumptions about their daily 

operation. In addition, the heat loads from electrical devices were factored into the envelope 

refrigeration load calculations. DOE proposed to incorporate 100 percent of the electrical energy 
69 

consumed to operate the devices that are internally located and to convert the electrical energy 

consumed to a thermal load. The associated thermal load was then used to calculate the 

additional refrigeration load using the nominal refrigeration EER values described in section 

III.B.3.c. DOE also proposed a variety of PTO values in the NOPR to account for reductions in 

energy use due to component control and hours of usage. 75 FR 186, 198 (Jan. 4, 2010). 

 BASF supported including electricity consumption as part of the energy calculation, and 

concurred with the duty cycle assumptions. (BASF, No. 0021.1 at p. 5) Master-Bilt and NorLake also agreed with the electrical duty cycle equation proposed by DOE. (Master-Bilt, No. 

0027.1 at p. 2; Nor-Lake, No. 0023.1 at p. 4) ACEEE supported the methods and assumptions for 

PTO values and electrical loads and agreed with the use of nameplate power ratings because it 

encouraged load reduction. (ACEEE, No. 0052.1 at p. 3) ThermalRite noted that while it did not 

fully understand how the proposed PTO values listed in the January 2010 NOPR were 

developed, it believed that the proposed values represented a fair method of comparison among 

manufacturers because the same assumptions are made for all users. ThermalRite asked that 

DOE ensure that the values include all device types. (ThermalRite, No. 0049.1 at p. 2) ORNL 

requested that DOE include the ground heater below the floor insulation as part of the energy use 

calculation. (ORNL, No. 0028.1 at p. 2) Craig Industries requested that DOE accommodate 

high-efficiency heater wires that apply heat on demand. (Craig Industries, Public Meeting 

Transcript, No. 0016 at p. 325 and No. 0054.1 at p. 3) Finally, Nor-Lake expressed the opinion 

that the proposed PTO values for lights are low because in most applications the lights would be 

shut off each night for 8 hours. (Nor-Lake, No. 0047.1 at p. 5) 
70 

 DOE notes support from BASF, Master-Bilt, Nor-Lake, ACEEE, and ThermalRite for its 

methodology and assumptions. DOE is also aware of the concerns presented by ORNL, Craig 

Industries, and Nor-Lake. However, since DOE will implement a component-based standard, 

electrical components not part of a door are not included in the component test or component 

metric. DOE notes that assemblers or manufacturers of complete walk-ins must still use lighting 

that complies with the efficacy standard prescribed in EPCA. (42 U.S.C. 6313(f)(1)(G)) DOE 

will continue to use the method proposed in the January 2010 NOPR to calculate the energy 

consumption of lights, sensors, and other miscellaneous electrical devices associated with walkin doors. Regarding Craig Industries’ specific comment about door heater wire, DOE’s PTO 

assumptions take into account demand-based control of components, which includes the loads 

from door heater wires. PTO assumptions are given in sections 4.4.2 and 4.5.2 of Appendix A 

for display and non-display doors, respectively. See section III.B.3.b for further discussion of 

electrical components of doors. 

C. Test Procedures for Refrigeration Systems

 The refrigeration system is the equipment that performs the mechanical work necessary 

to cool the interior space of a walk-in cooler or freezer. As previously discussed, DOE considers 

the refrigeration system an individual component of the walk-in cooler or walk-in freezer. 

Therefore, in this test procedure, DOE establishes a test of the performance of a refrigeration 

system itself, assuming nominal envelope characteristics. In the concurrent standards 

rulemaking, DOE intends to establish energy conservation standards for the refrigeration system. 
71 

See generally 75 FR 17080 (April 5, 2010). The following sections address issues raised by 

interested parties on the January 2010 NOPR and September 2010 SNOPR. 

1. Definition of Refrigeration System 

 In the January 2010 NOPR, DOE proposed a definition of refrigeration system that 

described three types of systems that would be covered: (1) single-package systems containing 

the condensing and evaporator units; (2) split systems with the condensing unit and unit cooler 

physically separated and connected via refrigerant piping; or (3) unit coolers that receive 

refrigerant from a compressor rack system shared with other refrigeration equipment. 75 FR at 

200 (Jan. 4, 2010). In the September 2010 SNOPR, DOE proposed minor revisions to that 

definition to clarify some of these terms. That notice proposed the following definitions: 

Refrigeration system means the mechanism (including all controls and other components 

integral to the system’s operation) used to create the refrigerated environment in the 

interior of a walk-in cooler or freezer, consisting of (1) a packaged system where the unit 

cooler and condensing unit are integrated into a single piece of equipment, (2) a split 

system with separate unit cooler and condensing unit sections, or (3) a unit cooler that is 

connected to a multiplex condensing system. 

75 FR 55068, 55093 (Sept. 9, 2010). 

 NRDC, Craig Industries, and Master-Bilt agreed with the revisions proposed in the 

September 2010 SNOPR. (NRDC, No. 0064.1 at p. 7; Craig Industries, No. 0068.1 at p. 5; 

Master-Bilt, No. 0069.1 at p. 3) Other interested parties did not agree with the classification 
72 

contained in the definition or the types of systems covered. NEEA stated that the three 

refrigeration types do not accurately represent the market, and recommended that the equipment 

classification should instead match the classifications contained in DOE’s regulations for 

commercial refrigeration equipment. (NEEA, No. 0061.1 at pp. 2 and 4) The Joint Utilities also 

disagreed with the concept of defining systems as “matched” (“packaged” or “split” systems as 

termed in the proposed definition) or “remote” (a unit cooler connected to a multiplex 

condensing system as in the proposed definition). (Joint Utilities, No. 0059.1 at p. 2) Like 

NEEA, the Joint Utilities suggested that DOE change its proposed definition by adopting the 

approach taken with the commercial refrigeration equipment efficiency regulations: “packaged” 

systems should be termed “self-contained condensing units” and all other condensing units 

should be considered “remote condensing units.” The Joint SNOPR comment also agreed with 

this approach, suggesting that DOE classify refrigeration systems as self-contained (packaged 

systems) or unit coolers connected to remote condensing units (both dedicated and multiplex). It 

also suggested that for remote condensing systems, any applicable energy conservation standards 

should only apply to the unit cooler. (Joint SNOPR Comment, No. 0074.1 at p. 3) 

 DOE believes the three types of refrigeration systems described in the definition 

accurately represent the range of refrigeration equipment that is used in walk-in coolers and 

freezers. Although the definition differs from the definition for commercial refrigeration 

equipment, there are key differences between commercial refrigeration equipment refrigeration 

systems and walk-in refrigeration systems that make a new definition necessary. NEEA and the 

Joint Utilities refer to two common types of commercial refrigeration equipment refrigeration 

units. Some are “self-contained” (meaning the entire refrigeration system is built into the case). 
73 

Others are “remote condensing” (meaning the unit cooler is built into the case, but the whole 

case is connected to a central system of compressors and condensers (called a “rack” or 

“multiplex condensing system”) that is connected to most or all of the refrigeration units in a 

building). The latter configuration is common in supermarkets. For all remote condensing 

systems, the commercial refrigeration equipment test procedure rulemaking assumed a certain 

efficiency of the multiplex condensing system and the standards rulemaking did not regulate this 

part of the equipment. 71 FR 71340 and 74 FR 1092. 

 However, “remote condensing” can also refer to a configuration in which the unit cooler 

is connected to a dedicated (that is, only serving that one unit) compressor and condenser that are 

located somewhere away from the walk-in. This configuration is very rare for commercial 

refrigeration equipment but comprises a large proportion of walk-in refrigeration system 

applications. For this reason, DOE does not agree with the suggestion of NEEA and the Joint 

Utilities that this configuration should be classified as “remote condensing” and does not agree 

that the compressor and condenser parts should not be covered under the walk-in coolers and 

freezers rulemaking. Rather, DOE believes that a dedicated condensing unit should be included 

in the rule, even if it is remotely located, because it could be viewed as part of the walk-in cooler 

as long as it is connected only to that cooler and not to other refrigeration equipment. For 

systems where the walk-in is connected to a multiplex condensing system that runs multiple 

pieces of equipment, the compressor and condenser would not be covered because they are not 

exclusively part of the walk-in. 
74 

 In consideration of the above, DOE believes the commercial refrigeration equipment 

definition cannot be applied to walk-ins, because there is a certain type of walk-in refrigeration 

— namely, a split system with a dedicated but remotely located condensing unit — that is highly 

represented in walk-ins but rarely, if ever, represented in commercial refrigeration equipment. 

Thus, while the Joint Comment compares walk-in refrigeration systems to commercial 

refrigeration equipment, DOE believes this is not a relevant comparison. A closer comparison 

would be to residential central air conditioners – an example of equipment that almost always 

has a dedicated, but remotely located, condensing unit. In that instance, DOE’s definition covers 

this type of remote condensing unit. Furthermore, DOE notes that manufacturers can optimize 

the dedicated, remote condensing unit with the unit cooler to take advantage of certain conditions 

such as low ambient outdoor temperatures. Therefore, DOE has retained the proposed 

definition’s coverage of dedicated remote condensing systems. To further clarify this coverage, 

DOE has added the term “dedicated” to describe packaged systems and split systems in the 

definition it is adopting today. 

2. Refrigeration Test Procedure: AHRI 1250 (I-P)-2009 

 DOE proposed to incorporate the industry standard AHRI 1250-2009, “2009 Standard for 

Performance Rating of Walk-In Coolers and Freezers,” into the test procedure. (The January 

2010 NOPR referred to the preliminary version of this standard, AHRI 1250P-2009. The 

SNOPR updated this reference to the final version.) 75 FR 186, 200-201 (Jan. 4, 2010) and 75 

FR 55068, 55086 (Sept. 9, 2010). DOE proposed that manufacturers use this standard to rate the 

refrigeration systems of walk-in coolers and freezers. 
75 

 AHRI 1250-2009 covers the testing of refrigeration systems for walk-in coolers and 

freezers, which includes unit coolers and condensing units that are sold together as a matched 

system, unit coolers and condensing units that are sold separately, and unit coolers connected to 

compressor racks. The procedure describes the method for measuring the refrigeration capacity 

and the electrical energy consumption for the condensing unit and the unit cooler, as well as the 

off-cycle fan energy and the defrost subsystem under specified test conditions. The standard test 

conditions specify the dry-bulb and wet-bulb temperatures of the air surrounding the unit cooler 

and the condensing unit. The standard test conditions are different for indoor and outdoor 

locations for the condensing unit and for coolers and freezers. 

 The AHRI procedure also specifies the calculations used to ascertain the nominal box 

loads under typical low-load and high-load conditions, expressed as a function of the ambient air 

temperature. (The “nominal box load” refers to the refrigeration load imposed on the system by 

the walk-in envelope.) During the test, the system must operate under steady-state conditions. 

For systems in which the condensing unit is located outdoors, the test procedure uses bin 

temperature data and bin hour data to represent the impact of the seasonal variation in outside 

ambient air temperature on energy use. The test procedure provides a calculation methodology to 

compute an annual walk-in efficiency factor (AWEF) for the refrigeration system under a 

specified load profile. For unit coolers and condensing units sold separately, the test procedure 

allows for testing the components individually and then calculating the system AWEF from the 

component test results. 
76 

 Several interested parties agreed with DOE’s proposed methodology. AHRI urged DOE 

to allow a rating of walk-in refrigeration systems using the calculation methodologies in the 

proposed protocols contained in AHRI 1250. (AHRI, No. 0070.1 at p. 2) American Panel, 

Thermo-Kool, Bally, and NRDC also supported DOE’s proposal to allow the evaporator and 

condensing unit to be tested separately according to the proposed methodology. (American 

Panel, No. 0057.1 at p. 1; Thermo-Kool, No. 0072.1 at p. 1; Bally, No. 0078.1 at p. 3; NRDC, 

No. 0064.1 at p. 3) Craig Industries supported a formula that would allow the efficiency of the 

refrigeration system to be calculated from testing data provided by each component supplier. 

(Craig, No. 0068.1 at p. 3) Heatcraft advised that the refrigeration system procedure should allow 

for testing new components. (Heatcraft, No. 0065.1 at p. 1) However, the Joint Utilities 

disagreed with the assumption in AHRI 1250-2009 that unit coolers and remote condensing units 

that are sold separately will be matched and installed together, and stated that AHRI 1250-2009 

does not allow unit coolers to be compared with each other unless they have been tested on the 

same condensing unit. (Joint Utilities, No. 0059.1 at p. 2) No parties opposed DOE’s proposal to 

allow evaporator and condensing unit to be tested separately. 

 DOE notes the support of AHRI, American Panel, and NRDC for the proposed method 

and incorporates it into this final rule. In response to Heatcraft’s suggestion that the procedure 

should allow for testing new components, DOE anticipates that the method will lead to 

manufacturers testing unit coolers and condensing units when they are manufactured separately, 

so that they can be used in new systems. Regarding the issues raised by Craig Industries and the 

Joint Utilities, DOE emphasizes that the proposed procedure contains a calculation method by 

which the overall refrigeration performance can be calculated using testing data from a 
77 

condensing unit and unit cooler, even if the two components are provided by different suppliers. 

The test results for a unit cooler or condensing unit are independent from whichever condensing 

unit or unit cooler is matched with the tested component. In contrast, the test results for each 

component are in the form of a performance curve to facilitate calculation of matched 

performance, which, as suggested by the Joint Utilities, does not lend itself to meaningful 

comparisons between unit coolers without matching the particular unit coolers with the same 

condensing unit. DOE acknowledges this limitation but believes it is important to maintain the 

results in terms of the performance curve to facilitate calculation of the performance of the 

system as a whole, because the entire refrigeration system is treated as a component under the 

approach adopted in today’s final rule. Given that the refrigeration system is treated as a single 

component under the procedure, the procedure offers a simple method for determining the 

energy efficiency profile of the walk-in refrigeration system because it allows the unit cooler and 

condensing unit to be tested separately. 

 Additionally, DOE notes that if unit coolers are tested and rated as if they were to be 

combined with a multiplex condensing system, they could be compared against each other. The 

test data for unit coolers in a mix-match system include the data necessary for calculating the 

unit cooler’s performance when paired with a multiplex condensing system. Thus, it would be 

relatively simple for manufacturers of unit coolers to provide both the performance data for 

matching purposes and the performance as connected to a multiplex condensing system. DOE 

may consider requiring this information as part of any related labeling requirements for WICF 

equipment. 
78 

 While interested parties generally agreed with the adoption of AHRI 1250-2009, others 

disagreed with how that method would be applied to different system configurations. The Joint 

Utilities and NEEA both recommended that all remote condensing systems be tested using the 

“walk-in unit cooler match to parallel rack system” test method and noted that the matched 

system approach only be used for self-contained condensing units. (Joint Utilities, No. 0059.1 at 

p. 3; NEEA, No. 0061.1 at p. 4) The Joint Utilities further stated that the proposed AHRI 1250-

2009 test method for rating dedicated remote condensing systems would create confusion and 

additional testing burden because there are many different test methods and categories for 

different locations and types of condensing units. (Joint Utilities, No. 0059.1 at pp. 2 and 5) 

Other interested parties questioned the methodology for rating unit coolers connected to 

multiplex condensing systems. American Panel stated that the exemption of multiplex equipment 

would give that equipment an unfair advantage over single piece equipment. (American Panel, 

No. 0057.1 at p. 3) Master-Bilt stated that the multiplex exemption seemed to suggest that any 

condensing unit connected to more than one unit cooler would not be covered. (Master-Bilt, No. 

0069.1 at p. 3) NRDC stated that the proposed equations for evaluating the energy use of units 

with indoor condensing units and those connected to multiplex condensing systems should 

account for differences in the systems’ ability to reject heat. (NRDC, No. 0064.1 at p. 7) 

 Addressing the comments from the Joint Utilities and NEEA, as discussed in section 

III.C.1, DOE considers dedicated remote condensing units as distinct from multiplex condensing 

systems in that dedicated remote condensers are part of only one walk-in, while multiplex 

condensing systems are connected to more than one walk-in or other unit of refrigeration 

equipment.. DOE believes that dedicated remote condensing units represent a substantial 
79 

opportunity for energy savings in a regulation for walk-in components because the configuration 

of a dedicated remote condensing unit is widespread in several market segments such as 

restaurants. Manufacturers can optimize the dedicated remote condensing unit with the unit 

cooler to take advantage of certain conditions such as low ambient outdoor temperatures. The 

approach suggested by the Joint Utilities and NEEA would exclude dedicated remote condensing 

units from this regulation, but DOE views these units as part of the walk-in cooler or freezer if 

the unit is connected only to the walk-in and not to any other refrigeration equipment. Therefore, 

the test procedure for walk-in refrigeration equipment accounts for these units. 

 To address Master-Bilt’s request for clarification, for systems where the walk-in is 

connected to a central multiplex condensing system that runs multiple pieces of equipment, the 

compressor and condenser would not be covered because they are not exclusively part of the 

walk-in. DOE realizes there are certain condensing units that are connected to more than one unit 

cooler inside a single walk-in. These systems would not be considered “multiplex condensing 

systems” because they are connected to a single walk-in. However, if the condensing unit were 

connected to more than one unit cooler inside more than one walk-in or other piece of 

equipment, DOE would consider that a multiplex condensing system because the system’s 

performance could not be attributed to one walk-in alone. While DOE understands American 

Panel’s concern that multiplex condensing systems could have an advantage because those 

condensing units would not need to be tested, the condensing unit and compressor part of a 

multiplex condensing system is not exclusively part of a walk-in unit. Therefore, DOE is not 

covering them in this test procedure. DOE notes that unit coolers connected to the multiplex 

condensing systems would still be considered part of the walk-in and would need to be tested. 
80 

The procedure considers the different performance of multiplex condensing systems and indoor 

condensing systems as recommended by NRDC. For multiplex condensing systems, the 

calculation of energy use includes a nominal efficiency that accounts for that type of system’s 

ability to reject heat. The rating conditions for indoor condensing units provide an opportunity 

for crediting energy savings that result from an increased ability to reject heat. 

 Finally, one interested party proposed to expand the test procedure to provide more 

information than DOE previously proposed. NRDC suggested that testing data should be input 

into standardized calculations that would determine the overall system performance for each 

application and recommended that performance data should be able to be interpolated or 

extrapolated for hot climates. (NRDC, No. 0064.1 at p. 3) DOE notes that standardized rating 

conditions are not typically application-specific and may not be useful for determining the 

performance of the system in conditions outside the rating conditions. To provide this flexibility, 

as suggested by NRDC, the AHRI 1250 test procedure contains provisions for conducting testing 

with application ratings to obtain the performance for a particular application. However, DOE 

emphasizes that the standardized rating conditions are useful for comparing systems with each 

other and must be used for evaluating a product’s compliance with a particular standard. 

3. Alternative Efficiency Determination Method 

 For some covered equipment, DOE has allowed manufacturers to use their own methods, 

whether a calculation or computer simulation, to rate their equipment after they substantiate 

those calculation or simulation methods with test data. The purpose of this provision is to reduce 
81 

the burden of testing customized, low-volume equipment. DOE has allowed rating methods in 

the form of alternate rating methods (ARMs) or alternative efficiency determination methods 

(AEDMs). An ARM, which is allowed for rating residential central air conditioners and heat 

pumps, must be a representation of the test data and calculations of a mechanical vaporcompression refrigeration cycle. Manufacturers may use an ARM after submitting 

documentation to DOE and receiving specific approval from DOE to use that ARM to rate their 

equipment. (10 CFR § 430.24(m)(4)-(6)) An AEDM, which is allowed for certain products and 

commercial equipment -- including electric motors, distribution transformers, and commercial 

heating, ventilating, air-conditioning, and water heating (HVAC and WH) equipment -- is a 

rating method derived from a mathematical model that represents the mechanical and electrical 

characteristics of the equipment and is based on engineering or statistical analysis, computer 

simulation or modeling, or other analytical evaluations of performance data. An AEDM must be 

substantiated by test data before it can be used to rate equipment. (10 CFR § 431.17(a)(2)-(3); 10 

CFR § 431.197(a)(2); and 10 CFR § 431.197(a)(2)-(3)) 

 For the walk-in coolers and freezers rulemaking, DOE introduced the concept of an 

AEDM at the Framework public meeting (February 4, 2009) and requested comment on whether 

it could be applied to walk-ins. At the Framework public meeting, DOE asked how an AEDM 

could be implemented for walk-ins, what a sufficient test sample size for validating an AEDM 

would be, and how accurate (to what percentage) an AEDM should be. DOE did not receive any 

feedback regarding these questions. Several interested parties did, however, raise concerns in 

written comments on the Framework and during the Framework public meeting about the 

potential for inconsistency among manufacturers’ rating methods. For example, Owens Corning 
82 

stated that a single AEDM should be accepted to keep comparisons consistent (instead of 

different AEDMs from different manufacturers), and Craig said that requiring manufacturers to 

follow the same model (that is, not allowing manufacturers to use their own AEDMs) would 

provide consistent information to end users. (Owens Corning, No. EERE-2008-BT-STD-0015-

0034.1 at p. 2; Craig, No. EERE-2008-BT-STD-0015-0025.1 at p. 5) DOE summarized and 

addressed these comments in the January NOPR. 75 FR 186, 190 (Jan. 4, 2010).As a result, DOE 

did not propose any specific provisions regarding AEDMs or any other provisions that would 

allow manufacturers to develop their own rating methods for walk-ins. Instead, DOE proposed 

its own calculation methodology for manufacturers to use in rating similar units of walk-in 

equipment. 75 FR 186, 191 (Jan. 4, 2010). 

 

While the procedure divides the envelope into its major components, the refrigeration 

system is considered as a single component. Consistent with this approach, DOE is incorporating 

a single metric to cover the performance of the refrigeration system. DOE noted in the 

September 2010 SNOPR that the proposed refrigeration test procedure, AHRI 1250 (I-P)-2009, 

“2009 Standard for Performance Rating of Walk-In Coolers and Freezers,” allows manufacturers 

to test condensing units and unit coolers separately in certain situations, and to calculate the 

performance of the combined system. DOE anticipated that this approach would reduce the 

overall testing burden by eliminating the need to test the many possible unit cooler and 

condensing unit combinations that could comprise a complete refrigeration system. 75 FR 55073 

(Sept. 9, 2010). In proposing this approach, DOE also recognized that there could still be some 

burdens due to system variations. To mitigate these burdens, DOE noted that it might consider 
83 

allowing manufacturers of refrigeration to use AEDMs to rate their equipment. 75 FR 55089 

(Sept. 9, 2010). 

 In comments on the September 2010 SNOPR, interested parties commented on the 

burden of testing refrigeration systems because a manufacturer’s product line may have many 

different condensing units and unit coolers, which may be similar, but not identical, and need to 

be tested individually. Craig Industries stated that even if unit coolers and condensing units could 

be tested separately, testing each component with all the options available would substantially 

increase the need for testing and would discourage manufacturers from improving their 

equipment. (Craig Industries, No. 0068.1 at p. 3) AHRI requested that DOE allow manufacturers 

to rate their equipment and demonstrate compliance with the Federal standard through the use of 

an AEDM to minimize testing burden. (AHRI, No. 0070.1 at p. 3) Manufacturers were also 

concerned about how they would rate custom units. Heatcraft stated that refrigeration system 

manufacturers would face an undue testing burden and asserted that manufacturers would not be 

able to sell a particular piece of equipment if it had been tested. (Heatcraft, No. 0065.1 at p. 2) 

DOE acknowledges that when a refrigeration system is tested, it undergoes some modifications 

in order to accommodate the apparatus for taking test measurements. As a result, these units can 

no longer be sold as new equipment after testing and are typically destroyed. This situation, in 

Heatcraft’s view, would prevent them from selling custom equipment if the inclusion of a 

custom piece requires a separate test of the refrigeration system. 

 DOE recognizes the potential for variability with respect to walk-in components, in terms 

of their physical characteristics and, consequently, their energy performance or efficiency. To 
84 

address Craig’s concern that testing all equipment variations would be burdensome, and AHRI’s 

request that DOE allow manufacturers to use AEDMs, DOE will continue to consider the 

application of AEDMs or ARMs. DOE recognizes the value of permitting the use of AEDMs 

and ARMs in limited instances and may consider the adoption of such methods for walk-in 

equipment, including the statistical basis and the sample size required to validate them, in a 

future rulemaking. 

 

D. Other Issues -- Definition of Walk-In Cooler or Freezer

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)) 

 During the public meeting for the January 2010 NOPR, Hired Hand and several 

interested parties stated that DOE should clarify the definition of walk-in coolers and walk-in 

freezers with respect to temperature limits. Multiple interested parties commented that DOE 
85 

should set an upper temperature limit for walk-ins. After reviewing the comments from 

interested parties, DOE proposed in the September 2010 SNOPR to modify the definition of 

“refrigerated” within the definition of walk-in cooler or freezer to mean at or below 55 °F. 75 FR 

55068, 55069 (Sept. 9, 2010). 

 The Joint Utilities, AHRI, American Panel, the Joint Manufacturers, NEEA, Craig 

Industries, Thermo-Kool, Master-Bilt, and Bally agreed to the proposed upper temperature limit 

of 55 °F for walk-ins. (Joint Utilities, No. 0059.1 at p. 6; AHRI, No. 0070.1 at p. 1; American 

Panel, No. 0057.1 at p.1; Joint Manufacturers, No. 0062.1 at p. 1, NEEA, No. 0061.1 at p. 2; 

Craig Industries, No. 0068.1 at p. 1; Thermo-Kool, No. 0072.1 at p. 1; Master-Bilt, No. 0069.1 at 

p. 1; Bally, No. 0078.1 at p.1) The Joint Utilities also recommended that DOE develop 

definitions for walk-in coolers and freezers that are similar to California Title 24, Buildings 

Efficiency Standards, which contain a definition for “refrigerated warehouse” that clarifies a 

temperature of 55 degrees or less. (Joint Utilities, No. 0059.1 at p. 6) NEEA suggested that walkin coolers and freezers are essentially buildings and should be modeled as such. (NEEA, No. 

0061.1 at p. 5) 

 

 DOE notes that any regulation it develops must be consistent with, and fall within the 

parameters of, the statutory provisions set by Congress. Working within the confines of the 

statutorily-prescribed definition of the walk-in definition, DOE is clarifying what the term 

“refrigerated” means in the context of the walk-in definition to help address the concerns raised 

by commenters. In particular, DOE is defining “refrigerated” for purposes of walk-ins to mean 

“held at a temperature at or below 55 degrees Fahrenheit using a refrigeration system” as 
86 

suggested by commenters. Adopting this approach should enable DOE to sufficiently account for 

the range of walk-in equipment that exist.

 In comments on the January 2010 NOPR, interested parties expressed concern about the 

potential for abuse in light of the breadth of the exclusion in the statute and requested that DOE 

clarify the scope of this clause. At the public meeting for the January 2010 NOPR, Craig 

Industries stated that the definition of “medical, scientific, and research walk-ins” should be 

better defined, and Hired Hand agreed that the definition is unclear. (Craig Industries, Public 

Meeting Transcript, No. 0016 at p. 19; Hired Hand, Public Meeting Transcript, No. 0016 at p. 

26) These commenters were concerned because the current statutory language does not account 

for the fact that, in practice, walk-ins may be used interchangeably for either food storage or 

medical, scientific, or research usage. Because a given walk-in sold by a company could be used 

in any of these types of applications, Craig Industries and Hired Hand were both concerned that a 

company could market its walk-in as medical equipment and avoid having to meet any energy 

efficiency standards. Craig Industries and Hired Hand requested that DOE work to improve the 

definition of exempted uses for walk-ins because the definition could create ambiguity and 

loopholes. (Craig Industries, Public Meeting Transcript, No. 0016 at p. 4; Hired Hand, No. 

0051.1 at p. 2) 

 DOE is sensitive to the potential for abuse regarding walk-ins. To ensure that such abuse 

does not occur and to help clarify the scope of the exclusion created by Congress, DOE notes 

that for any walk-in – including those components that are covered by today’s test procedure and 

any applicable standards that DOE may promulgate – a manufacturer seeking to avail itself of 
87 

the statutory exclusion would, consistent with the statute, need to affirmatively demonstrate to 

DOE that its equipment is “designed and marketed exclusively for medical, scientific, or 

research purposes.” 42 U.S.C. 6311(20)(B). Further, while DOE is currently unaware of any 

instances where this exclusion is being abused, DOE will monitor the situation and take steps to 

prevent these types of activities from occurring when it receives sufficient information 

substantiating the existence of such activities. In examining whether a given walk-in satisfies the 

statutory exclusion, DOE may consider a number of factors, including, but not limited to, how a 

particular walk-in has been designed, how it has been marketed, to whom the equipment has 

been distributed, and steps taken by manufacturers. Accordingly, while DOE appreciates the 

concerns raised by Craig Industries and Hired Hand, DOE has decided that, at this time, the 

exclusion set by Congress is sufficiently clear. DOE may revisit this issue in the future if 

necessary. 

 One commenter requested clarification of the 3,000 square foot provision. Bally 

suggested that DOE add a corroborating cubic foot threshold, and stated that the large variability 

in panel heights could impact the energy conservation standards. (Bally, No. 0078.1 at p.1) 

Under the component-level test procedures established today, a cubic foot threshold for a walk-in 

is not necessary. Rather, a panel is considered as an individual component and its dimensions, 

including its height, are accounted for in the calculation methodology that DOE developed. 

IV. Procedural Issues and Regulatory Review 
88 

A. Review Under Executive Order 12866

 The Office of Management and Budget 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.) requires preparation of an initial 

regulatory flexibility analysis (IFRA) for any rule that by law must be proposed for public 

comment, unless the agency certifies that the rule, if promulgated, will not have a significant 

economic impact on a substantial number of small entities. As required by Executive Order 

13272, “Proper Consideration of Small Entities in Agency Rulemaking,” 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 the General Counsel’s website: http://www.gc.doe.gov. 

 DOE reviewed the test procedures considered in today’s final rule under the provisions of 

the Regulatory Flexibility Act and the procedures and policies published on February 19, 2003. 
89 

 As discussed in detail below, DOE found that because these test procedures have not 

previously been required of manufacturers, all manufacturers, including small manufacturers, 

could experience a financial burden associated with new testing requirements. While examining 

this issue, DOE determined that it could not certify that this rule would not have a significant 

effect on a substantial number of small entities. Therefore, DOE prepared an Initial Regulatory 

Flexibility Analysis (IRFA) for this rulemaking. 75 FR 55068, 55087. The Final Regulatory 

Flexibility Analysis (FRFA) set forth below, which describes potential impacts on small 

businesses associated with walk-in cooler and freezer testing requirements, incorporates the 

IRFA and changes made to the IRFA in response to the comments from interested parties, 

including the Small Business Administration (SBA), on the September 2010 SNOPR. 

1. Statement of the need for, and objectives of, the rule 

 A statement of the need for, and objectives of, the rule is stated elsewhere in the preamble 

and not repeated here. 

2. Summary of the significant issues raised by the public comments, DOE’s response to these 

issues, and any changes made in the proposed rule as a result of such comments 

The comments received on the IRFA and the economic impacts of the rule and responses 

thereto are provided in the analysis below. 

 

3. Description and Estimated Number of Small Entities Regulated 

 DOE uses the SBA small business size standards published on January 31, 1996, as 

amended, to determine whether any small entities would be required to comply with the rule. 61 
90 

FR 3286; see also 65 FR 30836, 30850 (May 15, 2000), as amended. 65 FR 53533, 53545 

(September 5, 2000). 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 

www.sba.gov/idc/groups/public/documents/sba_homepage/serv_sstd_tablepdf.pdf. 

 In the January 2010 NOPR and September 2010 SNOPR, DOE classified walk-in cooler 

and freezer equipment manufacturing under NAICS 333415, “Air-Conditioning and Warm Air 

Heating Equipment and Commercial and Industrial Refrigeration Equipment Manufacturing,” 

which has a size standard of 750 employees. 75 FR 186, 204 (Jan. 4, 2010) and 75 FR 55068, 

55087 (Sept. 9, 2010). After reviewing industry sources and publicly available data, DOE 

identified at least 37 small manufacturers of walk-in cooler and freezer envelopes and at least 5 

small manufacturers of walk-in cooler and freezer refrigeration systems that met this criterion. 

DOE also noted that the walk-in industry can be characterized by a few manufacturers that are 

subsidiaries of much larger companies (that would not be considered small businesses) and a 

large number of small companies as categorized by NAICS code 333415. Furthermore, more 

than half of small walk-in manufacturers have 100 or fewer employees. 75 FR at 55088 (Sept. 9, 

2010). 

 Interested parties commented on the market characterization DOE presented in the 

September 2010 SNOPR. SBA agreed with DOE’s characterization of the walk-in manufacturing 

industry. (SBA, No. 0066.1 at p. 2) American Panel stated that most walk-in companies are small 

businesses and would be at a disadvantage compared to the large conglomerates. American Panel 
91 

characterized the majority of small walk-in manufacturers as making between $10 and $25 

million in sales while large manufacturers represent $75 million in walk-in sales and $250 

million in overall sales. (American Panel, No. 0057.1 at p. 3) American Panel stated that the cost 

of testing would be passed down to the product selling price, which would trickle down and 

seriously impact small business restaurant owners. (American Panel, No. 0057.1 at p. 4) Zero 

Zone agreed that small manufacturers would be impacted by the regulations and stated that many 

will not be able to stay in business once they are burdened with the costs of certification. (Zero 

Zone, No. 0077.1 at p. 2) 

 In response to comments on the January 2010 NOPR and September 2010 SNOPR 

regarding DOE’s proposed standards for WICF, DOE is taking a component-level approach in 

the WICF test procedure rulemaking. Specifically, DOE is establishing test procedures for 

individual components of a walk-in: panels, doors, and refrigeration systems. Manufacturers of 

these components will be required to test the components they manufacture for walk-ins and 

certify that they meet any applicable component performance standard. This approach will 

mitigate the overall burdens posed by this regulation and ensure that those burdens are borne on 

those manufacturers who are best suited and positioned to conduct these types of tests. See 

section III.A for further details on this approach. 

 As a result of this approach, DOE re-evaluated the number of small manufacturers it 

identified in the September 2010 SNOPR for this final rule. Because DOE is considering 

refrigeration systems as a single component under the proposed approach, DOE estimates that 

there are 4 small manufacturers of refrigeration systems. Furthermore, DOE notes that entities it 
92 

previously considered walk-in envelope manufacturers also manufacture the panels. As a result, 

DOE estimates that there are 37 small manufacturers of panels. For doors, DOE notes that some 

of the panel manufacturers make doors and others buy doors from suppliers. DOE researched 

manufacturers who solely manufacture the doors of WICF, and estimates that there are four 

small manufacturers of walk-in doors who do not also manufacture panels. DOE notes SBA’s 

and American Panel’s characterization of the walk-in industry as being composed mainly of 

small manufacturers. DOE believes the new approach of regulating WICFs at the component 

level will reduce burden on small manufacturers because the testing and compliance burden will 

be reduced due to an enhanced ability to apply the basic model concept. See section III.A.3.a for 

details. In response to American Panel’s comment that the cost of testing would affect small 

restaurant owners, DOE notes that this analysis considers entities who are directly regulated by 

this test procedure rulemaking (i.e., manufacturers). The concurrent energy conservation 

standards rulemaking will address effects on walk-in manufacturers’ customers. 

4. Description and Estimate of Compliance Requirements and Description of Steps to Minimize 

the Economic Impact on Small Entities. 

 DOE recognizes the particular burden of the test procedures on small manufacturers. 

DOE does not expect that small manufacturers would have fewer basic models or component 

types than large manufacturers. Therefore, a small manufacturer could have the same total cost 

of testing as a large manufacturer, but this cost would be a higher percentage of a small 

manufacturer’s annual revenues. Thus, the differential impact associated with walk-in cooler and 
93 

walk-in freezer test procedures on small businesses may be significant even if the overall testing 

burden is reduced as described elsewhere in the preamble. 

 Due to the nature of walk-in coolers and freezers within the appliance standards program, 

DOE is considering use of a component-based approach to walk-in standards, setting individual 

performance standards for each component. This approach would require the component 

manufacturers to test the components they manufacture for walk-in applications, comply with the 

applicable performance standard for those components, and certify to DOE that those 

components meet the standard. See section III.A for details on this approach. At this time there 

are no performance standards in place for walk-in equipment, as those standards are being 

developed in a concurrent rulemaking. Details on the performance standards rulemaking can be 

found on the DOE website at 

http://www1.eere.energy.gov/buildings/appliance_standards/commercial/wicf.html. However, 

manufacturers will be required to use these test procedures to certify performance once any final 

standards are issued and must use the test procedures outlined in this final rule if they make 

representations as to the performance of their components. 

 To further address concerns about costs, DOE is anticipating developing a sampling plan 

in a future rulemaking to determine how many units of each walk-in component must be tested. 

In such a rulemaking, DOE will consider the impacts to small businesses. 

a. Panel and Door Manufacturer Testing Impacts 
94 

In the September 2010 SNOPR, DOE proposed to require envelope manufacturers to test 

their equipment in accordance with several industry test standards: ASTM C1363-05, “Standard 

Test Method for Thermal Performance of Building Materials and Envelope Assemblies by 

Means of a Hot Box Apparatus;” DIN EN 13164:2009-02, “Thermal insulation products for 

buildings— Factory made products of extruded polystyrene foam (XPS)—Specification;” DIN 

EN 13165:2009-02, “Thermal insulation products for buildings— Factory made rigid 

polyurethane foam (PUR) products—Specification;” and NFRC 100-2010[E0A1], “Procedure 

for Determining Fenestration Product U-factors.” 

 DOE spoke with industry experts to determine the approximate cost of each test. Under 

the new component level approach to testing, entire walk-ins are not required to be tested or 

certified. Rather, component manufacturers are required to test and certify their own 

components. Therefore, DOE evaluated the cost of each test to the component manufacturer. For 

foam used in panels, a test using DIN EN 13164:2009-02 or DIN EN 13165:2009-02 costs 

approximately $5,000 for each type of foam, though DOE has found that most manufacturers use 

only one type. The test result would be used to calculate the LTTR for all the manufacturer’s 

panels that use that type of foam. For the panels themselves, a test using ASTM C1363-05 costs 

approximately $5,000. Manufacturers would need to test the core and edge U-factor of a pair of 4 

ft. by 8 ft. panels, for each foam type, frame type, and panel thickness they manufacture. DOE 

estimated that manufacturers use either one or two types of foam and may have up to nine 

different combinations of frame type and panel thickness. Using this estimate, the total cost of 

testing compliance with a panel standard could be up to an average of $5,000–$10,000 for the 

foam panels and $45,000 to test the U-factors of the different panel configurations. However, for 
95 

manufacturers who have fewer unique combinations of frame type and panel thickness, the 

testing cost would be substantially less. DOE has incorporated other burden reducing measures 

to reduce cost. Specifically, it incorporated a method that allows manufacturers to test a 

reference panel that is 4 ft. by 8 ft. and then calculate the U-factor of other panels of different 

dimensions from those test results as long as certain aspects of the panels are the same. See 

section III.B.2 for details. 

For doors, a test of door U-factor using NFRC 100 costs approximately $5,000. DOE 

estimates that a typical door manufacturer would have to certify up to 20 to 40 basic models of 

doors, which would cost $100,000 to $200,000 if each door were to be physically tested. 

However, NFRC 100 also permits computer modeling of a door’s U-factor, which could further 

reduce the testing cost. See section III.B.3 for discussion of the NFRC testing requirements for 

doors. 

The estimated costs only include the cost of one test on each basic model, and do not 

include additional testing on the same basic model that may be required as part of a sampling 

plan. As mentioned above, DOE anticipates developing sampling plans in a future rulemaking to 

determine how many tests need to be performed on the same type of envelope component, to 

ensure the test results are repeatable and statistically valid. 

b. Refrigeration System Manufacturer Testing Impacts 
96 

 The test procedure for refrigeration systems will require manufacturers to perform testing 

in accordance with a single industry test standard: AHRI 1250 (I-P)-2009, “2009 Standard for 

Performance Rating of Walk-In Coolers and Freezers.” DOE researched the cost of performing 

this test and, based on discussions with experts, estimates that a test using AHRI 1250 (I-P)-2009 

would likely cost approximately $8,500. DOE estimates that the total testing cost for a typical 

refrigeration manufacturer could be approximately $425,000, based on an estimate of 50 basic 

models, but that it could be higher for manufacturers of more customized equipment. For 

instance, a manufacturer with 200 basic models would incur a testing cost of approximately $1.7 

million. 

To address concerns of manufacturer impact, DOE is including burden-reducing 

measures for refrigeration system manufacturers. The test procedure referenced in this final rule, 

AHRI 1250-2009, allows for rating the condensing unit and the unit cooler separately and then 

calculating their combined efficiency. This reduces testing burden by not requiring testing of 

every combination. Allowing such a calculation to be used will significantly decrease the number 

of tests. See section III.C.2 for details. DOE also notes that the CCE final rule, published March 

7, 2011, allows that in general, manufacturers may elect to group individual models of 

equipment into basic models at their discretion to the extent the models have essentially identical 

electrical, physical, and functional characteristics that affect energy efficiency or energy 

consumption. Furthermore, manufacturers may rate models conservatively, meaning the tested 

performance of the model(s) must be at least as good as the certified rating, after applying the 

appropriate sampling plan. 76 FR 12429. DOE believes these provisions will reduce the burden 

of testing for refrigeration manufacturers because they will reduce the number of basic models a 
97 

manufacturer must test. DOE may also consider allowing manufacturers to use validated 

alternative methods to rate their equipment. See section III.C.3 for further discussion of these 

methods. 

 DOE also considered a number of alternatives to these test procedures, including test 

procedures that incorporate industry test standards other than the referenced standards, DIN EN 

13164:2009-02, DIN EN 13165:2009-02, ASTM C1363-05, and AHRI 1250-2009, all 

previously described in section III. (DOE also notes that NFRC 100, the test method adopted for 

determining the U-factor of doors, was the least burdensome test DOE identified.) Instead of 

requiring DIN EN 13164:2009-02 or DIN EN 13165:2009-02 for testing the long-term thermal 

properties of insulation, DOE could require only ASTM C518-04, “Standard Test Method for 

Steady-State Thermal Transmission Properties by Means of the Heat Flow Meter Apparatus,” 

which tests the thermal properties of insulation at a certain point in time (that is, the point of 

manufacture). This test could also be used in place of ASTM 1363-05. A test conducted as per 

ASTM C518-04 would cost approximately $500 to $1,000, as compared to $5,000 for a test 

conducted as per DIN EN 13164:2009-02 or DIN EN 13165:2009-02 and $5,000 for a test 

conducted as per ASTM C1363-05. DOE is including ASTM C1363-05 as part of the test 

procedure because heat conduction through structural members is a significant panel 

characteristic that is not addressed under ASTM C518-04. See section III.B.2.a for details. DOE 

is including DIN EN 13164:2009-02 and DIN EN 13165:2009-02 as part of the test procedure 

because these methods account for the effect of aging on foam’s insulation performance, a 

phenomenon that is not captured under ASTM C518-04. See section III.B.2.b for details. 
98 

C. Review Under the Paperwork Reduction Act of 1995

 Manufacturers of walk-in cooler and walk-in freezer components must certify to DOE 

that their equipment complies with any applicable energy conservation standard. In certifying 

compliance, manufacturers must test their equipment according to the DOE test procedure for 

walk-in cooler and walk-in freezer components, including any amendments adopted for that test 

procedure. DOE has adopted regulations for the certification and recordkeeping requirements 

for all covered consumer products and commercial equipment, including walk-in cooler and 

walk-in freezer components. 76 FR 12442 (March 7, 2011). The collection-of-information 

requirement for the certification and recordkeeping has been approved by OMB under control 

number 1910-1400. The public reporting burden for the certification is estimated to average 20 

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. 

 Public comment is sought regarding: whether this proposed collection of information is 

necessary for the proper performance of the functions of the agency, including whether the 

information shall have practical utility; the accuracy of the burden estimate; ways to enhance the 

quality, utility, and clarity of the information to be collected; and ways to minimize the burden of 

the collection of information, including through the use of automated collection techniques or 

other forms of information technology. Send comments on these or any other aspects of the 

collection of information to Charles Llenza (see ADDRESSES) and by e-mail to 

Christine_J._Kymn@omb.eop.gov. 
99 

 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. 

D. Review Under the National Environmental Policy Act of 1969

 In this final rule, DOE establishes a new test procedure for walk-in coolers and walk-in 

freezers. 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 rule 

establishes a test procedure without affecting the amount, quality or distribution of energy usage, 

and, therefore, will not result in any environmental impacts. Thus, this rulemaking is covered by 

Categorical Exclusion A5 under 10 CFR part 1021, subpart D, which applies to any rulemaking 

that does not result in any environmental impacts. Accordingly, neither an environmental 

assessment nor an environmental impact statement is required. 

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 
100 

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 today’s final rule. States can petition DOE for exemption from 

such preemption to the extent, and based on criteria, set forth in EPCA. (42 U.S.C. 6297(d)) 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 
101 

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. Pub. L. No. 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 http://www.gc.doe.gov. DOE examined today’s 

final rule according to UMRA and its statement of policy and determined that the rule contains 
102 

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. Today’s 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 
103 

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 today’s 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. 

Today’s regulatory action is not a significant regulatory action under Executive Order 

12866. Moreover, it would not have a significant adverse 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. 
104 

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 notice of proposed rulemaking 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 procedures addressed by this action incorporate the following commercial standards: 

ASTM C1363-05, AHRI 1250 (I-P)-2009, DIN EN 13164:2009-02, DIN EN 13165:2009–02, 

and NFRC 100-2010[E0A1]. DOE has evaluated these standards and is unable to conclude 

whether they fully comply with the requirements of section 32(b) of the FEAA (i.e. whether they 

were 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. 
105 

M. Congressional Notification

As required by 5 U.S.C. 801, DOE will report to Congress on the promulgation of today's 

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). 

 

107 

PART 431—ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL and 

INDUSTRIAL EQUIPMENT 

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

Authority: 42 U.S.C. 6291-6317. 

2. Section 431.302 is amended by adding, in alphabetical order, new definitions for 

“Display door,” “Display panel,” “Door”, “Envelope,” “K-factor,” “Panel,” “Refrigerated,” 

“Refrigeration system,” and “U-factor” to read as follows: 

§ 431.302 Definitions concerning walk-in coolers and walk-in freezers. 

* * * * * 

 Display door means a door designed for product movement, display, or both, rather than 

the passage of persons. 

 Display panel means a panel that is entirely or partially comprised of glass, a transparent 

material, or both and is used for display purposes. 

 Door means an assembly installed in an opening on an interior or exterior wall that is 

used to allow access or close off the opening and that is movable in a sliding, pivoting, hinged, 

or revolving manner of movement. For walk-in coolers and walk-in freezers, a door includes the 

door panel, glass, framing materials, door plug, mullion, and any other elements that form the 

door or part of its connection to the wall. 
108 

 Envelope means— 

 (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. 

 K-factor means the thermal conductivity of a material. 

* * * * * 

 Panel means a construction component that is not a door and is used to construct the 

envelope of the walk-in, i.e., elements that separate the interior refrigerated environment of the 

walk-in from the exterior. 

 Refrigerated means held at a temperature at or below 55 degrees Fahrenheit using a 

refrigeration system. 

 Refrigeration system means the mechanism (including all controls and other components 

integral to the system’s operation) used to create the refrigerated environment in the interior of a 

walk-in cooler or freezer, consisting of: 

 (1) A packaged dedicated system where the unit cooler and condensing unit are 

integrated into a single piece of equipment; or 

 (2) A split dedicated system with separate unit cooler and condensing unit sections; or 

 (3) A unit cooler that is connected to a multiplex condensing system. 
109 

 U-factor means the heat transmission in a unit time through a unit area of a specimen or 

product and its boundary air films, induced by a unit temperature difference between the 

environments on each side. 

* * * * * 

3. Section 431.303 is amended by: 

a. Re-designating paragraph (b) as paragraph (c); 

b. Adding at the end of the sentence in redesignated paragraph (c)(1), “and Appendix A to 

Subpart R of Part 431.” 

c. Adding new paragraphs (b), (c)(2), (d), and (e) to read as follows. 

§ 431.303 Materials incorporated by reference. 

* * * * * 

(b) AHRI. Air-Conditioning, Heating, and Refrigeration Institute, 2111 Wilson Boulevard, Suite 

500, Arlington, VA 22201, (703) 600-0366, or www.ahrinet.org. 

(1) AHRI 1250 (I-P)-2009, (“AHRI 1250”), 2009 Standard for Performance Rating of Walk-In 

Coolers and Freezers, approved 2009, IBR approved for § 431.304. 

(2) [Reserved]. 

(c) * * * 

(1) * * * 

(2) ASTM C1363-05, (“ASTM C1363”), Standard Test Method for Thermal Performance of 

Building Materials and Envelope Assemblies by Means of a Hot Box Apparatus, approved May 

1, 2005, IBR approved for Appendix A to Subpart R of part 431. 
110 

(d) CEN. European Committee for Standardization (French: Norme or German: Norm), Avenue 

Marnix 17, B-1000 Brussels, Belgium, Tel: + 32 2 550 08 11, Fax: + 32 2 550 08 19 or 

http://www.cen.eu/. 

(1) DIN EN 13164:2009-02, (“DIN EN 13164”), Thermal insulation products for buildings – 

Factory made products of extruded polystyrene foam (XPS) – Specification, approved February 

2009, IBR approved for Appendix A to Subpart R of part 431. 

(2) DIN EN 13165:2009-02, (“DIN EN 13165”), Thermal insulation products for buildings – 

Factory made rigid polyurethane foam (PUR) products – Specification, approved February 2009, 

IBR approved for Appendix A to Subpart R of part 431. 

(e) NFRC. National Fenestration Rating Council, 6305 Ivy Lane, Ste. 140, Greenbelt, MD 

20770, (301) 589-1776, or www.nfrc.org/. 

(1) NFRC 100-2010[E0A1], (“NFRC 100”), Procedure for Determining Fenestration Product Ufactors, approved June 2010, IBR approved for Appendix A to Subpart R of part 431. 

(2) [Reserved]. 

4. Section 431.304 is amended by re-designating paragraphs (b)(2), (b)(3), (b)(4), and 

(b)(5) as (b)(1), (b)(2), (b)(3), and (b)(4), respectively, and by adding new paragraphs (b)(5), 

(b)(6), (b)(7), (b)(8), and (b)(9) to read as follows. 

§ 431.304 Uniform test method for the measurement of energy consumption of walk-in 

coolers and walk-in freezers. 

* * * * * 

 (b) Testing and Calculations. 

* * * * * 
111 

 (5) Determine the U-factor, conduction load, and energy use of walk-in cooler and walkin freezer display panels, floor panels, and non-floor panels by conducting the test procedure set 

forth in Appendix A, sections 4.1, 4.2, and 4.3, respectively. 

 (6) Determine the energy use of walk-in cooler and walk-in freezer display doors and 

non-display doors by conducting the test procedure set forth in Appendix A, sections 4.4 and 4.5, 

respectively. 

 (7) Determine the Annual Walk-in Energy Factor of walk-in cooler and walk-in freezer 

refrigeration systems by conducting the test procedure set forth in AHRI 1250 (incorporated by 

reference; see § 431.303). 

 (8) Determine the annual energy consumption of walk-in cooler and walk-in freezer 

refrigeration systems: 

 (i) For systems consisting of a packaged dedicated system or a split dedicated system, 

where the condensing unit is located outdoors, by conducting the test procedure set forth in 

AHRI 1250 and recording the annual energy consumption term in the equation for annual walkin energy factor in section 7 of AHRI 1250: 

Annual Energy Consumption =෍ ܧሺݐ௝ሻ

௡

௝ୀଵ

where tj and n represent the outdoor temperature at each bin j and the number of hours in each 

bin j, respectively, for the temperature bins listed in Table D1 of AHRI 1250. 

 (ii) For systems consisting of a packaged dedicated system or a split dedicated system 

where the condensing unit is located in a conditioned space, by performing the following 

calculation: 
112 

Annual Energy Consumption ൌ ቆ 0.33 ൈ ܪܮܤሶ ൅ 0.67 ൈ ܮܮܤሶ

Annual Walk-in Energy Factorቇ ൈ 8760

where ܪܮܤሶ and ܮܮܤሶ for refrigerator and freezer systems are defined in sections 6.2.1 and 6.2.2, 

respectively, of AHRI 1250 and the annual walk-in energy factor is calculated from the results of 

the test procedures set forth in AHRI 1250. 

 (iii) For systems consisting of a single unit cooler or a set of multiple unit coolers 

serving a single piece of equipment and connected to a multiplex condensing system, by 

performing the following calculation: 

Annual Energy Consumption ൌ ቆ 0.33 ൈ ܪܮܤሶ ൅ 0.67 ൈ ܮܮܤሶ

Annual Walk-in Energy Factorቇ ൈ 8760

where ܪܮܤሶ and ܮܮܤሶ for refrigerator and freezer systems are defined in section 7.9.2.2 and 

7.9.2.3, respectively, of AHRI 1250 and the annual walk-in energy factor is calculated from the 

results of the test procedures set forth in AHRI 1250. 

5.Appendix A to subpart R of part 431 is added to read as follows: 

Appendix A to Subpart R of Part 431—Uniform Test Method for the Measurement of 

Energy Consumption of the Components of Envelopes of Walk-In Coolers and Walk-In 

Freezers 

1.0 Scope 

This appendix covers the test requirements used to measure the energy consumption of the 

components that make up the envelope of a walk-in cooler or walk-in freezer. 
113 

2.0 Definitions 

The definitions contained in § 431.302 are applicable to this appendix. 

3.0 Additional Definitions 

3.1 Automatic door opener/closer means a device or control system that “automatically” 

opens and closes doors without direct user contact, such as a motion sensor that senses 

when a forklift is approaching the entrance to a door and opens it, and then closes the door 

after the forklift has passed. 

3.2 Core region means the part of the panel that is not the edge region. 

3.3 Edge region means a region of the panel that is wide enough to encompass any framing 

members and edge effects. If the panel contains framing members (e.g. a wood frame) then 

the width of the edge region must be as wide as any framing member plus 2 in. ± 0.25 in. If 

the panel does not contain framing members then the width of the edge region must be 4 in 

± 0.25 in. For walk-in panels that utilize vacuum insulated panels (VIP) for insulation, the 

width of the edge region must be the lesser of 4.5 in. ± 1 in. or the maximum width that 

does not cause the VIP to be pierced by the cutting device when the edge region is cut. 

3.4 Surface area means the area of the surface of the walk-in component that would be 

external to the walk-in. For example, for panel, the surface area would be the area of the 

side of the panel that faces the outside of the walk-in. It would not include edges of the 

panel that are not exposed to the outside of the walk-in. 

3.5 Rating conditions means, unless explicitly stated otherwise, all conditions shown in 

Table A.1. For installations where two or more walk-in envelope components share any 

surface(s), the “external conditions” of the shared surface(s) must reflect the internal 
114 

conditions of the adjacent walk-in. For example, if a walk-in component divides a walk-in 

freezer from a walk-in cooler, then the internal conditions are the freezer rating conditions 

and the external conditions are the cooler rating conditions. 

3.6 Percent time off (PTO) means the percent of time that an electrical device is assumed to 

be off. 

Table A.1 - Temperature Conditions 

Internal Temperatures (cooled space within the envelope) Value 

Cooler Dry Bulb Temperature 35 °F 

Freezer Dry Bulb Temperature -10 °F 

External Temperatures (space external to the envelope) Value

Freezer and Cooler Dry Bulb Temperatures 75 °F 

Subfloor Temperatures Value 

Freezer and Cooler Dry Bulb Temperatures 55 °F

4.0 Calculation Instructions 

4.1 Display Panels 

(a) Calculate the U-factor of the display panel in accordance with section 5.3 of this 

appendix, Btu/ h-ft2-

o

F. 

(b) Calculate the display panel surface area, as defined in section 3.4 of this appendix, Adp, 

ft2, with standard geometric formulas or engineering software. 

(c) Calculate the temperature differential, ΔTdp, °F, for the display panel, as follows: 

 

∆Tୢ୮ ൌ หTDB,ୣ୶୲,ୢ୮ െ TDB,୧୬୲,ୢ୮ ห (4-1) 

Where: 

TDB,ext,dp = dry-bulb air external temperature, °F, as prescribed in Table A.1; and 
115 

TDB,int, dp = dry-bulb air temperature internal to the cooler or freezer, °F, as prescribed in Table 

A.1. 

(d) Calculate the conduction load through the display panel, Qcond-dp, Btu/h, as follows: 

 

Qୡ୭୬ୢ,ୢ୮ ൌ Aୢ୮ ൈ ∆Tୢ୮ ൈ Uୢ୮ (4-2) 

Where: 

Adp = surface area of the walk-in display panel, ft2

; 

ΔTdp = temperature differential between refrigerated and adjacent zones, °F; and 

Udp = thermal transmittance, U-factor, of the display panel in accordance with section 5.3 of this 

appendix, Btu/ h-ft2-

o

F. 

(e) Select Energy Efficiency Ratio (EER), as follows: 

(1) For coolers, use EER = 12.4 Btu/W-h 

(2) For freezers, use EER = 6.3 Btu/W-h 

(f) Calculate the total daily energy consumption, Edp, kWh/day, as follows: 

Eୢ୮ ൌ Qౙ౥౤ౚ,ౚ౦

EER

ൈ

ଶସ ୦ൈଵ ୩W

ଵ ୢୟ୷ ൈଵ଴଴଴ W (4-3) 

Where: 

Qcond, dp = the conduction load through the display panel, Btu/h; and 
116 

EER = EER of walk-in (cooler or freezer), Btu/W-h. 

4.2 Floor Panels 

(a) Calculate the surface area, as defined in section 3.4 of this appendix, of the floor panel 

edge, as defined in section 3.3, Afp edge, ft2

, with standard geometric formulas or engineering 

software as directed in section 5.1 of this appendix. 

(b) Calculate the surface area, as defined in section 3.4 of this appendix, of the floor panel 

core, as defined in section 3.2, Afp core, ft2

, with standard geometric formulas or engineering 

software as directed in section 5.1 of this appendix. 

(c) Calculate the total area of the floor panel, Afp, ft2, as follows: 

A୤୮ ൌ A୤୮ ୡ୭୰ୣ ൅ A୤୮ ୣୢ୥ୣ (4-4) 

Where: 

Afp core = floor panel core area, ft2; and 

Afp edge = floor panel edge area, ft2. 

(d) Calculate the temperature differential of the floor panel, ΔΤfp, °F, as follows: 

 

∆T୤୮ ൌ หTୣ୶୲,୤୮ െ TDB,୧୬୲,୤୮ห (4-5) 

Where: 
117 

Text, fp = subfloor temperature, °F, as prescribed in Table A.1; and 

TDB,int, fp = dry-bulb air internal temperature, °F, as prescribed in Table A.1. If the panel spans 

both cooler and freezer temperatures, the freezer temperature must be used. 

(e) Calculate the floor foam degradation factor, DFfp, unitless, as follows: 

DF୤୮ ൌ RLTTR,౜౦

Rబ,౜౦

 (4-6) 

Where: 

RLTTR,fp = the long term thermal resistance R-value of the floor panel foam in accordance with 

section 5.2 of this appendix, h-ft2-

o

F/Btu; and 

Ro,fp = the R-value of foam determined in accordance with ASTM C518 (incorporated by 

reference; see section § 431.303) for purposes of compliance with the appropriate energy 

conservation standard, h-ft2

-

o

F/Btu. 

(f) Calculate the U-factor for panel core region modified by the long term thermal 

transmittance of foam, ULT,fp core, Btu/h-ft2

-

o

F, as follows: 

ULT,୤୮ ୡ୭୰ୣ ൌ U౜౦ ౙ౥౨౛

DF౜౦

 (4-7) 

Where: 

Ufp core = the U-factor in accordance with section 5.1 of this appendix, Btu/h-ft2

-

o

F; and 
118 

DFfp = floor foam degradation factor, unitless. 

(g) Calculate the overall U-factor of the floor panel, Ufp, Btu/h-ft2-

o

F, as follows: 

U୤୮ ൌ A౜౦ ౛ౚౝ౛ൈ U౜౦ ౛ౚౝ౛ାA౜౦ ౙ౥౨౛ൈULT,౜౦ ౙ౥౨౛

A౜౦

 (4-8) 

Where: 

Afp edge = area of floor panel edge, ft2;

Ufp edge = U-factor for panel edge area in accordance with section 5.1 of this appendix, Btu/h-ft2-

o

F; 

Afp core = area of floor panel core, ft2

; 

ULT,fp core = U-factor for panel core region modified by the long term thermal transmittance of 

foam, Btu/h-ft2

-

o

F; and 

Afp = total area of the floor panel, ft2

. 

(h) Calculate the conduction load through floor panels, Qcond-fp, Btu/h, 

Qୡ୭୬ୢି୤୮ ൌ ∆T୤୮ ൈ A୤୮ ൈ U୤୮ (4-9) 

Where: 

ΔTfp = temperature differential across the floor panels, oF; 

Afp = total area of the floor panel, ft2

; and
119 

Ufp = overall U-factor of the floor panel, Btu/h-ft2-

o

F. 

(i) Select Energy Efficiency Ratio (EER), as follows: 

(1) For coolers, use EER = 12.4 Btu/W-h 

(2) For freezers, use EER = 6.3 Btu/W-h 

(j) Calculate the total daily energy consumption, Efp, kWh/day, as follows: 

E୤୮ ൌ Qౙ౥౤ౚష౜౦

EER

ൈ

ଶସ ୦ൈଵ ୩W

ଵ ୢୟ୷ ൈଵ଴଴଴ W (4-10) 

Where: 

Qcond-fp = the conduction load through the floor panel, Btu/h; and 

EER = EER of walk-in (cooler or freezer), Btu/W-h. 

4.3 Non-Floor Panels 

(a) Calculate the surface area, as defined in section 3.4, of the non-floor panel edge, as 

defined in section 3.3, Anf edge, ft2

, with standard geometric formulas or engineering 

software as directed in section 5.1 of this appendix. 

(b) Calculate the surface area, as defined in section 3.4, of the non-floor panel core, as 

defined in section 3.2, Anf core, ft2, with standard geometric formulas or engineering software 

as directed in section 5.1 of this appendix. 

(c) Calculate total non-floor panel area, Anf, ft2

: 
120 

Anf = Anf edge+ Anf core (4-11) 

Where: 

Anf edge = non-floor panel edge area, ft2; and 

Anf core = non-floor panel core area, ft2

. 

(d) Calculate temperature differential, ΔTnf , °F: 

∆T୬୤, ൌ หTDB,ୣ୶୲,୬୤ െ TDB,୧୬୲,୬୤ห (4-12) 

Where: 

TDB,ext, nf = dry-bulb air external temperature, °F, as prescribed in Table A.1; and 

TDB,int, nf = dry-bulb air internal temperature, °F, as prescribed in Table A.1. If the non-floor panel 

spans both cooler and freezer temperatures, then the freezer temperature must be used. 

(e) Calculate the non-floor foam degradation factor, DFnf, unitless, as follows: 

DF୬୤ ൌ RLTTR,౤౜,

R౥,౤౜

 (4-13) 

Where: 

RLTTR,nf = the R-value of the non-floor panel foam in accordance with section 5.2 of this 

appendix, h- ft2

-

o

F /Btu; and 
121 

Ro,nf = the R-value of foam determined in accordance with ASTM C518 (incorporated by 

reference; see section § 431.303) for purposes of compliance with the appropriate energy 

conservation standard, h-ft2-

o

F/Btu. 

(f) Calculate the U-factor, ULT,nf core, Btu/h-ft2

-

o

F, as follows: 

ULT,୬୤ ୡ୭୰ୣ ൌ U౤౜ ౙ౥౨౛

DF౤౜

 (4-14) 

Where: 

Unf core = the U-factor, in accordance with section 5.1 of this appendix, of non-floor panel, Btu/hft2

-

o

F; and 

DFnf = the non-floor foam degradation factor, unitless. 

(g) Calculate the overall U-factor of the non-floor panel, Unf, Btu/h-ft2-

o

F, as follows: 

U୬୤ ൌ A౤౜ ౛ౚౝ౛ൈ U౤౜ ౛ౚౝ౛ାA౤౜ ౙ౥౨౛ൈULT,౤౜ ౙ౥౨౛

A౤౜

 (4-15) 

Where: 

Anf edge = area of non-floor panel edge, ft2

;

Unf edge = U-factor for non-floor panel edge area in accordance with section 5.1 of this appendix, 

Btu/h-ft2

-

o

F; 

Anf core = area of non-floor panel core, ft2

; 
122 

ULT,nf core = U-factor for non-floor panel core region modified by the long term thermal 

transmittance of foam, Btu/h-ft2

-

o

F; and 

Anf = total area of the non- floor panel, ft2. 

(h) Calculate the conduction load through non-floor panels, Qcond-nf, Btu/h, 

Qୡ୭୬ୢି୬୤ ൌ ∆T୬୤ ൈ A୬୤ ൈ U୬୤ (4-16) 

Where: 

ΔTnf = temperature differential across the non-floor panels, o

F; 

Anf = total area of the non-floor panel, ft2; and

Unf = overall U-factor of the non-floor panel, Btu/h-ft2-

o

F. 

(i) Select Energy Efficiency Ratio (EER), as follows: 

(1) For coolers, use EER = 12.4 Btu/W-h 

(2) For freezers, use EER = 6.3 Btu/W-h 

(j) Calculate the total daily energy consumption, Enf, kWh/day, as follows: 

E୬୤ ൌ Qౙ౥౤ౚష౤౜

EER

ൈ

ଶସ ୦ൈଵ ୩W

ଵ ୢୟ୷ ൈଵ଴଴଴ W (4-17) 

Where: 

Qcond-nf = the conduction load through the non-floor panel, Btu/h; and 
123 

EER = EER of walk-in (cooler or freezer), Btu/W-h. 

4.4 Display Doors 

4.4.1 Conduction through Display Doors 

(a) Calculate the U-factor of the door in accordance with section 5.3 of this appendix, 

Btu/h-ft2

-

o

F 

(b) Calculate the surface area, as defined in section 3.4 of this appendix, of the display 

door, Add, ft2, with standard geometric formulas or engineering software. 

(c) Calculate the temperature differential, ΔTdd, °F, for the display door as follows: 

∆Tୢୢ ൌ หTDB,ୣ୶୲,ୢୢ െ TDB,୧୬୲,ୢୢห (4-18) 

Where: 

TDB,ext, dd = dry-bulb air temperature external to the display door, °F, as prescribed in Table A.1; 

and 

TDB,int, dd = dry-bulb air temperature internal to the display door, °F, as prescribed in Table A.1. 

(d) Calculate the conduction load through the display doors, Qcond-dd, Btu/h, as follows: 

Qୡ୭୬ୢ,ୢୢ ൌ Aୢୢ ൈ ∆Tୢୢ ൈ Uୢୢ (4-19) 

Where: 
124 

∆Tୢୢ = temperature differential between refrigerated and adjacent zones, °F; 

Add = surface area walk-in display doors, ft2; and 

Udd = thermal transmittance, U-factor of the door, in accordance with section 5.3 of this 

appendix, Btu/ h-ft2-

o

F. 

4.4.2 Direct Energy Consumption of Electrical Component(s) of Display Doors 

 Electrical components associated with display doors could include, but are not limited to: 

heater wire (for anti-sweat or anti-freeze application); lights (including display door lighting 

systems); control system units; and sensors. 

(a) Select the required value for percent time off (PTO) for each type of electricity 

consuming device, PTOt (%) 

(1) For lights without timers, control system or other demand-based control, PTO = 

25 percent. For lighting with timers, control system or other demand-based control, PTO = 

50 percent. 

(2) For anti-sweat heaters on coolers (if included): Without timers, control system or 

other demand-based control, PTO = 0 percent. With timers, control system or other 

demand-based control, PTO = 75 percent. For anti-sweat heaters on freezers (if included): 

Without timers, control system or other auto-shut-off systems, PTO = 0 percent. With 

timers, control system or other demand-based control, PTO = 50 percent. 

(3) For all other electricity consuming devices: Without timers, control system, or 

other auto-shut-off systems, PTO = 0 percent. If it can be demonstrated that the device is 

controlled by a preinstalled timer, control system or other auto-shut-off system, PTO = 25 

percent. 
125 

(b) Calculate the power usage for each type of electricity consuming device, Pdd-comp,u,t, 

kWh/day, as follows: 

Pୢୢିୡ୭୫୮,୳,୲ ൌ P୰ୟ୲ୣୢ,୳,୲ ൈ ൫1 െ PTO୳,୲൯ൈn୳,୲ ൈ 24h/day (4-20) 

Where: 

u = the index for each of type of electricity-consuming device located on either (1) the interior 

facing side of the display door or within the inside portion of the display door, (2) the exterior 

facing side of the display door, or (3) any combination of (1) and (2). For purposes of this 

calculation, the interior index is represented by u = int and the exterior index is represented by u 

= ext. If the electrical component is both on the interior and exterior side of the display door then 

u = int. For anti-sweat heaters sited anywhere in the display door, 75 percent of the total power is 

be attributed to u = int and 25 percent of the total power is attributed to u = ext; 

t = index for each type of electricity consuming device with identical rated power; 

Prated,u,t = rated power of each component, of type t, kW; 

PTOu,t = percent time off, for device of type t, %; and 

nu,t = number of devices at the rated power of type t, unitless. 

(c) Calculate the total electrical energy consumption for interior and exterior power, Pdd-tot, 

int (kWh/day) and Pdd-tot, ext (kWh/day), respectively, as follows: 

Pୢୢି୲୭୲,୧୬୲ ൌ ∑ Pୢୢିୡ୭୫୮,୧୬୲,୲

୲

ଵ (4-21) 
126 

Pୢୢି୲୭୲,ୣ୶୲ ൌ ∑ Pୢୢିୡ୭୫୮,ୣ୶୲,୲

୲

ଵ (4-22) 

Where: 

t = index for each type of electricity consuming device with identical rated power; 

Pdd-comp,int, t = the energy usage for an electricity consuming device sited on the interior facing 

side of or in the display door, of type t, kWh/day; and 

Pdd-comp,ext, t = the energy usage for an electricity consuming device sited on the external facing 

side of the display door, of type t, kWh/day. 

(d) Calculate the total electrical energy consumption, Pdd-tot, (kWh/day), as follows: 

Pୢୢି୲୭୲ ൌ Pୢୢି୲୭୲,୧୬୲ ൅ Pୢୢି୲୭୲,ୣ୶୲ (4-23) 

Where: 

Pdd-tot,int = the total interior electrical energy usage for the display door, kWh/day; and 

Pdd-tot,ext = the total exterior electrical energy usage for the display door, kWh/day. 

4.4.3 Total Indirect Electricity Consumption Due to Electrical Devices 

(a) Select Energy Efficiency Ratio (EER), as follows: 

(1) For coolers, use EER = 12.4 Btu/Wh 

(2) For freezers, use EER = 6.3 Btu/Wh 

(b) Calculate the additional refrigeration energy consumption due to thermal output from 

electrical components sited inside the display door, Cdd-load, kWh/day, as follows: 
127 

Cୢୢି୪୭ୟୢ ൌ Pୢୢି୲୭୲,୧୬୲ ൈ

ଷ.ସଵଶ

EER

B୲୳

Wି୦ (4-24) 

Where: 

EER = EER of walk-in cooler or walk-in freezer, Btu/W-h; and 

Pdd-tot,int = The total internal electrical energy consumption due for the display door, kWh/day. 

4.4.4 Total Display Door Energy Consumption 

(a) Select Energy Efficiency Ratio (EER), as follows: 

(1) For coolers, use EER = 12.4 Btu/W-h 

(2) For freezers, use EER = 6.3 Btu/W-h 

(b) Calculate the total daily energy consumption due to conduction thermal load, Edd, thermal, 

kWh/day, as follows: 

Eୢୢ,୲୦ୣ୰୫ୟ୪ ൌ Qౙ౥౤ౚ,ౚౚ

EER

ൈ

ଶସ ୦ൈଵ ୩W

ଵ ୢୟ୷ ൈଵ଴଴଴ W (4-25) 

Where: 

Qcond, dd = the conduction load through the display door, Btu/h; and 

EER = EER of walk-in (cooler or freezer), Btu/W-h. 

(c) Calculate the total energy, Edd,tot, kWh/day, 
128 

Eୢୢ,୲୭୲ ൌ Eୢୢ,୲୦ୣ୰୫ୟ୪ ൅ Pୢୢି୲୭୲ ൅ Cୢୢି୪୭ୟୢ (4-26) 

Where: 

Edd, thermal = the total daily energy consumption due to thermal load for the display door, 

kWh/day; 

Pdd-tot = the total electrical load, kWh/day; and 

Cdd-load = additional refrigeration load due to thermal output from electrical components 

contained within the display door, kWh/day. 

4.5 Non-Display Doors 

4.5.1 Conduction through Non-Display Doors 

(a) Calculate the surface area, as defined in section 3.4 of this appendix, of the non-display 

door, And, ft2, with standard geometric formulas or with engineering software. 

(b) Calculate the temperature differential of the non-display door, ΔTnd,°F, as follows: 

 

∆T୬ୢ ൌ หTDB,ୣ୶୲,୬ୢ െ TDB,୧୬୲,୬ୢห (4-27) 

Where: 

TDB,ext, nd = dry-bulb air external temperature, °F, as prescribed by Table A.1; and 

TDB,int, nd = dry-bulb air internal temperature, °F, as prescribed by Table A.1. If the component 

spans both cooler and freezer spaces, the freezer temperature must be used. 

(c) Calculate the conduction load through the non-display door: Qcond-nd, Btu/h, 
129 

Qୡ୭୬ୢି୬ୢ ൌ ∆T୬ୢ ൈ A୬ୢ ൈ U୬ୢ (4-28) 

Where: 

ΔTnd = temperature differential across the non-display door, oF; 

Und = thermal transmittance, U-factor of the door, in accordance with section 5.3 of this 

appendix, Btu/ h-ft2

-

o

F; and 

And = area of non-display door, ft2

. 

4.5.2 Direct Energy Consumption of Electrical Components of Non-Display Doors 

 Electrical components associated with a walk-in non-display door comprise any 

components that are on the non-display door and that directly consume electrical energy. This 

includes, but is not limited to, heater wire (for anti-sweat or anti-freeze application), control 

system units, and sensors. 

(a) Select the required value for percent time off for each type of electricity consuming 

device, PTOt (%) 

(1) For lighting without timers, control system or other demand-based control, PTO = 

25 percent. For lighting with timers, control system or other demand-based control, PTO = 

50 percent. 

(2) For anti-sweat heaters on coolers (if included): Without timers, control system or 

other demand-based control, PTO = 0 percent. With timers, control system or other 

demand-based control, PTO = 75 percent. For anti-sweat heaters on freezers (if included): 
130 

Without timers, control system or other auto-shut-off systems, PTO = 0 percent. With 

timers, control system or other demand-based control, PTO = 50 percent. 

(3) For all other electricity consuming devices: Without timers, control system, or 

other auto-shut-off systems, PTO = 0 percent. If it can be demonstrated that the device is 

controlled by a preinstalled timer, control system or other auto-shut-off system, PTO = 25 

percent. 

(b) Calculate the power usage for each type of electricity consuming device, Pnd-comp,u,t, 

kWh/day, as follows: 

P୬ୢିୡ୭୫୮,୳,୲ ൌ P୰ୟ୲ୣୢ,୳,୲ ൈ ൫1 െ PTO୳,୲൯ൈn୳,୲ ൈ 24h/day (4-29) 

Where: 

u = the index for each of type of electricity-consuming device located on either (1) the interior 

facing side of the display door or within the inside portion of the display door, (2) the exterior 

facing side of the display door, or (3) any combination of (1) and (2). For purposes of this 

calculation, the interior index is represented by u = int and the exterior index is represented by u 

= ext. If the electrical component is both on the interior and exterior side of the display door then 

u = int. For anti-sweat heaters sited anywhere in the display door, 75 percent of the total power is 

be attributed to u=int and 25 percent of the total power is attributed to u=ext; 

t = index for each type of electricity consuming device with identical rated power; 

Prated,u,t = rated power of each component, of type t, kW; 

PTOu,t = percent time off, for device of type t, %; and 

nu,t = number of devices at the rated power of type t, unitless. 
131 

(c) Calculate the total electrical energy consumption for interior and exterior power, Pnd-tot, 

int (kWh/day) and Pnd-tot, ext (kWh/day), respectively, as follows: 

P୬ୢି୲୭୲,୧୬୲ ൌ ∑ P୬ୢିୡ୭୫୮,୧୬୲,୲

୲

ଵ (4-30) 

P୬ୢି୲୭୲,ୣ୶୲ ൌ ∑ P୬ୢିୡ୭୫୮,ୣ୶୲,୲

୲

ଵ (4-31) 

Where: 

t = index for each type of electricity consuming device with identical rated power; 

Pnd-comp,int, t = the energy usage for an electricity consuming device sited on the internal facing 

side or internal to the non-display door, of type t, kWh/day; and 

Pnd-comp,ext, t = the energy usage for an electricity consuming device sited on the external facing 

side of the non-display door, of type t, kWh/day. For anti-sweat heaters, 

(d) Calculate the total electrical energy consumption, Pnd-tot, kWh/day, as follows: 

P୬ୢି୲୭୲ ൌ P୬ୢି୲୭୲,୧୬୲ ൅ P୬ୢି୲୭୲,ୣ୶୲ (4-32) 

Where: 

Pnd-tot,int = the total interior electrical energy usage for the non-display door, of type t, kWh/day; 

and 

Pnd-tot,ext = the total exterior electrical energy usage for the non-display door, of type t, kWh/day. 
132 

4.5.3 Total Indirect Electricity Consumption Due to Electrical Devices 

(a) Select Energy Efficiency Ratio (EER) , as follows: 

(1) For coolers, use EER = 12.4 Btu/Wh 

(2) For freezers, use EER = 6.3 Btu/Wh 

(b) Calculate the additional refrigeration energy consumption due to thermal output from 

electrical components associated with the non-display door, Cnd-load, kWh/day, as follows: 

C୬ୢି୪୭ୟୢ ൌ P୬ୢି୲୭୲,୧୬୲ ൈ

ଷ.ସଵଶ

EER

B୲୳

Wି୦ (4-33) 

Where: 

EER = EER of walk-in cooler or freezer, Btu/W-h; and 

Pnd-tot,int = the total interior electrical energy consumption for the non-display door, kWh/day. 

4.5.4 Total Non-Display Door Energy Consumption 

(a) Select Energy Efficiency Ratio (EER) , as follows: 

(1) For coolers, use EER = 12.4 Btu/W-h 

(2) For freezers, use EER = 6.3 Btu/W-h 

(b) Calculate the total daily energy consumption due to thermal load, End, thermal, kWh/day, 

as follows: 
133 

E୬ୢ,୲୦ୣ୰୫ୟ୪ ൌ Qౙ౥౤ౚష౤ౚ

EER

ൈ

ଶସ ୦ൈଵ ୩W

ଵ ୢୟ୷ ൈଵ଴଴଴ W (4-34) 

Where: 

Qcond-nd = the conduction load through the non-display door, Btu/hr; and 

EER = EER of walk-in (cooler or freezer), Btu/W-h. 

(c) Calculate the total energy, End,tot, kWh/day, as follows: 

E୬ୢ,୲୭୲ ൌ E୬ୢ,୲୦ୣ୰୫ୟ୪ ൅ P୬ୢି୲୭୲ ൅ C୪୭ୟୢ (4-35) 

Where: 

End, thermal = the total daily energy consumption due to thermal load for the non-display door, 

kWh/day; 

Pnd-tot = the total electrical energy consumption, kWh/day; and 

Cnd-load = additional refrigeration load due to thermal output from electrical components 

contained on the inside face of the non-display door, kWh/day. 

5.0 Test Methods and Measurements 

5.1 Measuring Floor and Non-floor Panel U-factors 

Follow the test procedure in ASTM C1363, (incorporated by reference; see § 431.303), 

exactly, with these exceptions: 

(1) Test Sample Geometry Requirements 
134 

(i) Two (2) panels, 8 ft. ± 1 ft. long and 4 ft. ± 1 ft. wide must be used. 

(ii) The panel edges must be joined using the manufacturer’s panel interface joining 

system (e.g., camlocks, standard gasketing, etc.). 

(iii) The Panel Edge Test Region, see figure 1, must be cut using the following 

dimensions: 

1. If the panel contains framing members (e.g. a wood frame), then the 

width of edge (W) must be as wide as any framing member plus 2 in. 

± 0.25 in. For example, if the face of the panel contains 1.5 in. thick 

framing members around the edge of the panel, then width of edge 

(W) = 3.5 in. ± 0.25 in and the Panel Edge Test Region would be 7 

in. ± 0.5 in. wide. 

2. If the panel does not contain framing members, then the width of 

edge (W) must be 4 in ± 0. 25 in. 

3. Walk-in panels that utilize vacuum insulated panels (VIP) for 

insulation, width of edge (W) = the lesser of 4.5 in. ± 1 in. or the 

maximum width that does not cause the VIP to be pierced by the 

cutting device when the edge region is cut. 

(iv) Panel Core Test Region of length Y and height Z, see Figure 1, must also be cut 

from one of the two panels such that panel length = Y + X, panel height = Z +X 

where X=2W.
135 

Figure 1 ASTM C1363 Test Regions (Note: diagram not drawn to scale) 

(2) Testing Conditions 

(i) The air temperature on the “hot side”, as denoted in ASTM C1363, of the nonfloor panel should be maintained at 75 °F ± 1 °F. 

1. Exception: When testing floor panels, the air temperature should be 

maintained at 55 °F ± 1 °F. 

(ii) The temperature on the “cold side”, as denoted in ASTM C1363, of the panel 

should be maintained at 35 °F ± 1 °F for the panels used for walk-in coolers and 

−10 °F ± 1 °F for panels used for walk-in freezers. 
136 

(iii) The air velocity must be maintained as natural convection conditions as 

described in ASTM C1363. The test must be completed using the masked 

method and with surround panel in place as described in ASTM C1363. 

(3) Required Test Measurements 

(i) Non-floor Panels 

1. Panel Edge Region U-factor: Unf, edge

2. Panel Core Region U-factor: Unf, core

(ii) Floor Panels 

1. Floor Panel Edge Region U-factor: Ufp, edge

2. Floor Panel Core Region U-factor: Ufp, core

5.2 Measuring Long Term Thermal Resistance (LTTR) of Insulating Foam 

Follow the test procedure in Annex C of DIN EN 13164 or Annex C of DIN EN 13165 (as 

applicable), (incorporated by reference; see § 431.303), exactly, with these exceptions: 

(1) Temperatures During Thermal Resistance Measurement 

(i) For freezers: 35 °F ± 1 °F must be used 

(ii) For coolers: 55 °F ± 1 must be used 

(2) Sample Panel Preparation 

(i) A 800mm × 800mm square (× thickness of the panel) section cut from the 

geometric center of the panel that is being tested must be used as the sample for 

completing DIN EN 13165. 
137 

(ii) A 500mm × 500mm square (× thickness of the panel) section cut from the 

geometric center of the panel that is being tested must be used as the sample for 

completing DIN EN 13164. 

(3) Required Test Measurements 

(i) Non-floor Panels 

1. Long Term Thermal Resistance: RLTTR,nf

(ii) Floor Panels 

1. Long Term Thermal Resistance: RLTTR,fp

5.3 U-factor of Doors and Display Panels 

(a) Follow the procedure in NFRC 100, (incorporated by reference; see § 431.303), exactly, 

with these exceptions: 

(1) The average convective heat transfer coefficient on both interior and exterior 

surfaces of the door should be based on the coefficients described in section 4.3 of NFRC 

100. 

(2) Internal conditions: 

(i) Air temperature of 35 °F (1.7 °C) for cooler doors and −10 °F (−23.3 °C) for 

freezer doors 

(ii) Mean inside radiant temperature must be the same as shown in section 

5.3(a)(2)(i), above. 

(3) External conditions 

(i) Air temperature of 75 °F (23.9 °C) 
138 

(ii) Mean outside radiant temperature must be the same as section 5.3(a)(3)(i), 

above. 

(4) Direct solar irradiance = 0 W/m2

 (Btu/h-ft2). 

(b) Required Test Measurements 

(i) Display Doors and Display Panels 

1. Thermal Transmittance: Udd

(ii) Non-Display Door 

1. Thermal Transmittance: Und