Document ID: EPA-HQ-OAR-2019-0698-0070
Agency: epa
Document Type: Rule
Title: Protection of Stratospheric Ozone: Listing of Substitutes under the Significant New Alternatives Policy Program
Posted Date: 2021-05-06T04:00Z

[Federal Register Volume 86, Number 86 (Thursday, May 6, 2021)]
[Rules and Regulations]
[Pages 24444-24474]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-08968]

[[Page 24443]]

Vol. 86

Thursday,

No. 86

May 6, 2021

Part II

 Environmental Protection Agency

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

40 CFR Part 82

Protection of Stratospheric Ozone: Listing of Substitutes Under the 
Significant New Alternatives Policy Program; Final Rule

  Federal Register / Vol. 86 , No. 86 / Thursday, May 6, 2021 / Rules 
and Regulations  

[[Page 24444]]

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

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 82

[EPA-HQ-OAR-2019-0698; FRL-10020-41-OAR]
RIN 2060-AU81

Protection of Stratospheric Ozone: Listing of Substitutes Under 
the Significant New Alternatives Policy Program

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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

SUMMARY: Pursuant to the U.S. Environmental Protection Agency's (EPA) 
Significant New Alternatives Policy program, this action lists certain 
substances in the refrigeration and air conditioning sector. For the 
retail food refrigeration--medium-temperature stand-alone units (new) 
end-use, EPA is listing three substitutes as acceptable subject to 
narrowed use limits. For the residential and light commercial air 
conditioning and heat pumps (new) end-use, EPA is listing six 
substitutes as acceptable subject to use conditions. Through this 
action, EPA is incorporating by reference the 2019 Underwriters 
Laboratories (UL) Standard 60335-2-40, 3rd Edition, which establishes 
requirements for the evaluation of electrical air conditioners, heat 
pumps, and dehumidifiers, and safe use of flammable refrigerants. This 
action also removes an acceptable subject to use conditions listing for 
the fire suppression sector because EPA more recently listed the 
substitute as acceptable with no use restrictions.

DATES: This rule is effective June 7, 2021. The incorporation by 
reference of certain publications listed in the rule is approved by the 
Director of the Federal Register as of June 7, 2021.

ADDRESSES: EPA has established a docket for this action under Docket ID 
No. EPA-HQ-OAR-2019-0698. All documents in the docket are listed on the 
https://www.regulations.gov website. Although listed in the index, some 
information is not publicly available, e.g., Confidential Business 
Information (CBI) or other information whose disclosure is restricted 
by statute. Certain other material, such as copyrighted material, is 
not placed on the internet and will be publicly available only in hard 
copy form. Publicly available docket materials are available 
electronically through https://www.regulations.gov or in hard copy at 
the Air and Radiation Docket, EPA/DC, EPA West, Room 3334, 1301 
Constitution Avenue NW, Washington, DC 20460. EPA is temporarily 
suspending its Docket Center and Reading Room for public visitors, with 
limited exceptions, to reduce the risk of transmitting COVID-19. Our 
Docket Center staff will continue to provide remote customer service 
via email, phone, and webform. For further information on EPA Docket 
Center services and the current status, please visit us online at 
https://www.epa.gov/dockets.

FOR FURTHER INFORMATION CONTACT: Christina Thompson, Stratospheric 
Protection Division, Office of Atmospheric Programs (Mail Code 6205T), 
Environmental Protection Agency, 1200 Pennsylvania Ave. NW, Washington, 
DC 20460; telephone number: 202-564-0983; email address: 
thompson.christina@epa.gov. Notices and rulemakings under EPA's 
Significant New Alternatives Policy program are available on EPA's 
Stratospheric Ozone website at https://www.epa.gov/snap/snap-regulations.

SUPPLEMENTARY INFORMATION:

Table of Contents

I. General Information
    A. Executive Summary and Background
    B. Does this action apply to me?
    C. What acronyms and abbreviations are used in the preamble?
II. What is EPA finalizing in this action?
    A. Retail Food Refrigeration--Listing of R-448A, R-449A and R-
449B as Acceptable, Subject to Narrowed Use Limits, for Retail Food 
Refrigeration--Medium-Temperature Stand-Alone Units (New)
    1. Background on Retail Food Refrigeration--Medium-Temperature 
Stand-Alone Units (New)
    2. What are R-448A, R-449A and R-449B and how do they compare to 
other refrigerants in the same end-use?
    3. AHRI Petition
    4. What is EPA's final listing decision for R-448A, R-449A and 
R-449B?
    5. How is EPA responding to comments on retail food 
refrigeration--medium-temperature stand-alone units (new)?
    B. Residential and Light Commercial Air Conditioning and Heat 
Pumps--Listing of R-452B, R-454A, R-454B, R-454C, and R-457A as 
Acceptable, Subject to Use Conditions, for Use in Residential and 
Light Commercial Air Conditioning and Heat Pumps End-Use for New 
Equipment; and R-32 as Acceptable, Subject to Use Conditions, for 
Use in Residential and Light Commercial Air Conditioning and Heat 
Pumps--Equipment Other Than Self-Contained Room Air Conditioners, 
for New Equipment
    1. What use conditions is EPA finalizing?
    2. Background on Residential and Light Commercial Air 
Conditioning and Heat Pumps (New)
    3. What are the ASHRAE classifications for refrigerant 
flammability?
    4. What are R-32, R-452B, R-454A, R-454B, R-454C, and R-457A and 
how do they compare to other refrigerants in the same end-use?
    5. Why is EPA finalizing these specific use conditions?
    6. What additional information is EPA including in these 
listings?
    7. How is EPA responding to comments on residential and light 
commercial air conditioning and heat pumps?
    C. Total Flooding: Removal of Powdered Aerosol E From the List 
of Substitutes Acceptable Subject to Use Conditions
III. How is EPA responding to other public comments?
IV. Statutory and Executive Order Reviews
    A. Executive Order 12866: Regulatory Planning and Review and 
Executive Order 13563: Improving Regulation and Regulatory Review
    B. Paperwork Reduction Act (PRA)
    C. Regulatory Flexibility Act (RFA)
    D. Unfunded Mandates Reform Act (UMRA)
    E. Executive Order 13132: Federalism
    F. Executive Order 13175: Consultation and Coordination With 
Indian Tribal Governments
    G. Executive Order 13045: Protection of Children From 
Environmental Health and Safety Risks
    H. Executive Order 13211: Actions That Significantly Affect 
Energy Supply, Distribution, or Use
    I. National Technology Transfer and Advancement Act
    J. Executive Order 12898: Federal Actions To Address 
Environmental Justice in Minority Populations and Low-Income 
Population
    K. Congressional Review Act (CRA)
V. References

I. General Information

A. Executive Summary and Background

    This final rule lists new alternatives for the refrigeration and 
air conditioning sector and changes an existing listing for the fire 
suppression sector. Specifically, EPA is:
     Listing R-448A, R-449A and R-449B as acceptable, subject 
to narrowed use limits, for use in retail food refrigeration--medium-
temperature stand-alone units for new equipment;
     Listing R-452B, R-454A, R-454B, R-454C and R-457A as 
acceptable, subject to use conditions, for use in residential and light 
commercial air conditioning (AC) and heat pumps for new equipment; and 
R-32 as acceptable, subject to use conditions, for use in residential 
and light commercial AC and heat pumps--equipment other than self-
contained room air conditioners, for new equipment; and
     Removing Powdered Aerosol E from the list of fire 
suppression substitutes acceptable subject to use conditions in total 
flooding applications.

[[Page 24445]]

    EPA is finalizing these new listings after its evaluation of human 
health and environmental information for these substitutes under the 
Significant New Alternatives Policy (SNAP) program. The Agency is 
taking final action on these new listings in the refrigeration and air 
conditioning sector and the change to the listings in the fire 
suppression sector based on consideration of the information that 
supported the June 12, 2020 Notice of Proposed Rulemaking (``2020 
NPRM'') (85 FR 35874), the public comments and publicly-available 
information that EPA has included in the docket. This action provides 
additional flexibility for industry by providing new options in 
specific uses.
    EPA is not taking final action at this time on listings for three 
foam blowing agent blends for extruded polystyrene: Boardstock and 
billet that were also proposed in the 2020 NPRM. Based on public 
comments and new information that EPA has received after issuing the 
proposed rule, the Agency is considering future action on these 
substitutes. EPA's consideration of options for these substitutes is 
not related to and does not affect this final action on the remainder 
of the proposal.
    In this final action, EPA refers to listings made in a final rule 
issued July 20, 2015, at 80 FR 42870 (``2015 Rule''). The 2015 Rule, 
among other things, changed the listings for certain hydrofluorocarbons 
(HFCs) and blends from acceptable to unacceptable in various end-uses 
in the aerosols, refrigeration and air conditioning, and foam blowing 
sectors. After a challenge to the 2015 Rule, the United States Court of 
Appeals for the District of Columbia Circuit (``the court'') issued a 
partial vacatur of the 2015 Rule ``to the extent it requires 
manufacturers to replace HFCs with a substitute substance'' \1\ and 
remanded the rule to the Agency for further proceedings.\2\ The court 
also upheld EPA's listing changes as being reasonable and not 
``arbitrary and capricious.'' \3\ This final rule is not EPA's response 
to the court's decision.
---------------------------------------------------------------------------

    \1\ Mexichem Fluor, Inc. v. EPA, 866 F.3d 451, 462 (D.C. Cir. 
2017).
    \2\ Later, the court issued a similar decision on portions of a 
similar final rule issued December 1, 2016 at 81 FR 86778 (``2016 
Rule''). See Mexichem Fluor, Inc. v. EPA, Judgment, Case No. 17-1024 
(D.C. Cir., April 5, 2019), 760 Fed. Appx. 6 (Mem). That rule is not 
relevant for this action.
    \3\ Mexichem Fluor, 866 F.3d at 462-63.
---------------------------------------------------------------------------

SNAP Program Background
    The SNAP program implements section 612 of the Clean Air Act (CAA). 
Several major provisions of section 612 are:
1. Rulemaking
    Section 612(c) requires EPA to promulgate rules making it unlawful 
to replace any class I (chlorofluorocarbon (CFC), halon, carbon 
tetrachloride, methyl chloroform, methyl bromide, 
hydrobromofluorocarbon, and chlorobromomethane) or class II 
(hydrochlorofluorocarbon (HCFC)) ozone-depleting substances (ODS) with 
any substitute that the Administrator determines may present adverse 
effects to human health or the environment where the Administrator has 
identified an alternative that (1) reduces the overall risk to human 
health and the environment and (2) is currently or potentially 
available.
2. Listing of Unacceptable/Acceptable Substitutes
    Section 612(c) requires EPA to publish a list of the substitutes 
that it finds to be unacceptable for specific uses and to publish a 
corresponding list of acceptable substitutes for specific uses.
3. Petition Process
    Section 612(d) grants the right to any person to petition EPA to 
add a substance to, or delete a substance from, the lists published in 
accordance with section 612(c).
4. 90-Day Notification
    Section 612(e) directs EPA to require any person who produces a 
chemical substitute for a class I substance to notify the Agency not 
less than 90 days before a new or existing chemical is introduced into 
interstate commerce for significant new use as a substitute for a class 
I substance. The producer must also provide the Agency with the 
producer's unpublished health and safety studies on such substitutes.
    The regulations for the SNAP program are promulgated at 40 CFR part 
82, subpart G, and the Agency's process for reviewing SNAP submissions 
is described in regulations at 40 CFR 82.180. Under these rules, the 
Agency has identified five types of listing decisions: Acceptable; 
acceptable subject to use conditions; acceptable subject to narrowed 
use limits; unacceptable; and pending (40 CFR 82.180(b)). Use 
conditions and narrowed use limits are both considered ``use 
restrictions,'' as described below. Substitutes that are deemed 
acceptable with no use restrictions (no use conditions or narrowed use 
limits) can be used for all applications within the relevant end-uses 
in the sector. After reviewing a substitute, the Agency may determine 
that a substitute is acceptable only if certain conditions in the way 
that the substitute is used are met to minimize risks to human health 
and the environment. EPA describes such substitutes as ``acceptable 
subject to use conditions.'' (40 CFR 82.180(b)(2)). For some 
substitutes, the Agency may permit a narrowed range of use within an 
end-use or sector. For example, the Agency may limit the use of a 
substitute to certain end-uses or specific applications within an 
industry sector. EPA describes these substitutes as ``acceptable 
subject to narrowed use limits.'' Under the narrowed use limit, users 
intending to adopt these substitutes ``must ascertain that other 
alternatives are not technically feasible.'' (40 CFR 82.180(b)(3)).
    In making decisions regarding whether a substitute is acceptable or 
unacceptable, and whether substitutes present risks that are lower than 
or comparable to risks from other substitutes that are currently or 
potentially available in the end-uses under consideration, EPA examines 
the criteria in 40 CFR 82.180(a)(7): (i) Atmospheric effects and 
related health and environmental impacts; (ii) general population risks 
from ambient exposure to compounds with direct toxicity and to 
increased ground-level ozone; (iii) ecosystem risks; (iv) occupational 
risks; (v) consumer risks; (vi) flammability; and (vii) cost and 
availability of the substitute.
    Many SNAP listings include ``comments'' or ``further information'' 
to provide additional information on substitutes. Since this additional 
information is not part of the regulatory decision, these statements 
are not binding for use of the substitute under the SNAP program. 
However, regulatory requirements so listed are binding under other 
regulatory programs (e.g., worker protection regulations promulgated by 
the U.S. Occupational Safety and Health Administration (OSHA)). The 
``further information'' classification does not necessarily include all 
other legal obligations pertaining to the use of the substitute. While 
the items listed are not legally binding under the SNAP program, EPA 
encourages users of substitutes to apply all statements in the 
``further information'' column in their use of these substitutes. In 
many instances, the information simply refers to sound operating 
practices that have already been identified in existing industry and/or 
building codes or standards. Thus, many of the statements, if adopted, 
would not require the affected user to make

[[Page 24446]]

significant changes in existing operating practices.
    For additional information on the SNAP program, visit the SNAP 
portion of EPA's Ozone Layer Protection website at https://www.epa.gov/snap. Copies of the full lists of acceptable substitutes for ODS in all 
industrial sectors are available at https://www.epa.gov/snap/snap-substitutes-sector. For more information on the Agency's process for 
administering the SNAP program or criteria for evaluation of 
substitutes, refer to the initial SNAP rulemaking published March 18, 
1994 (59 FR 13044), codified at 40 CFR part 82, subpart G. SNAP 
decisions and the appropriate Federal Register citations found at: 
https://www.epa.gov/snap/snap-regulations. Substitutes listed as 
unacceptable; acceptable, subject to narrowed use limits; or 
acceptable, subject to use conditions, are also listed in the 
appendices to 40 CFR part 82, subpart G.

B. Does this action apply to me?

    The following list identifies regulated entities that may be 
affected by this rule and their respective North American Industrial 
Classification System (NAICS) codes:

 All Other Basic Organic Chemical Manufacturing (NAICS 325199)
 Air Conditioning and Warm Air Heating Equipment and Commercial 
and Industrial Refrigeration Equipment Manufacturing (NAICS 333415)
 Refrigeration Equipment and Supplies Merchant Wholesalers 
(NAICS 423740)
 Supermarkets and Other Grocery (except Convenience) Stores 
(NAICS 44511 & 445110)
 Convenience Stores (NAICS 445120)
 Limited-Service Restaurants (NAICS 722513)
 Cafeterias, Grill Buffets, and Buffets (NAICS 722514)
 Snack and Nonalcoholic Beverage Bars (NAICS 722515)
 Fire Protection (NAICS 922160)

    This list is not intended to be exhaustive, but rather to provide a 
guide for readers regarding entities likely to be affected by this 
action. To determine whether your facility, company, business, or 
organization could be affected by this action, you should carefully 
examine the regulations at 40 CFR part 82, subpart G and the revisions 
below. If you have questions regarding the applicability of this action 
to a particular entity, consult the person listed in the FOR FURTHER 
INFORMATION CONTACT section.

C. What acronyms and abbreviations are used in the preamble?

    Below is a list of acronyms and abbreviations used in the preamble 
of this document:

AC--Air Conditioning
ACCA--Air Conditioning Contractors of America
ADA--Americans with Disabilities Act
AEL--Acceptable Exposure Limit
AHIA--American Industrial Hygiene Association
AHJ--Authority Having Jurisdiction
AHRI--Air-Conditioning, Heating, and Refrigeration Institute
AHRTI--Air-Conditioning, Heating, and Refrigeration Technology 
Institute
Alliance--Alliance for Responsible Atmospheric Policy
ANSI--American National Standards Institute
ASHRAE--American Society of Heating, Refrigerating and Air-
Conditioning Engineers
CAA--Clean Air Act
CARB--California Air Resources Board
CAS Reg. No.--Chemical Abstracts Service Registry Identification 
Number
CBI--Confidential Business Information
CFC--Chlorofluorocarbon
CFR--Code of Federal Regulations
CRA--Congressional Review Act
CO2--Carbon Dioxide
DOE--United States Department of Energy
EIA--Environmental Investigation Agency
EPA--United States Environmental Protection Agency
FR--Federal Register
GSHP--Ground-Source Heat Pump
GWP--Global Warming Potential
HARDI--Heating, Air-conditioning, & Refrigeration Distributors 
International
HCFC--Hydrochlorofluorocarbon
HFC--Hydrofluorocarbon
HFO--Hydrofluoroolefin
HVAC--Heating, Ventilation, and Air Conditioning
HPPH--Heat Pump Pool Heaters
HPWH-- Heat Pump Water Heaters
ICF--ICF International, Inc.
IEC--International Electrotechnical Commission
IPCC--Intergovernmental Panel on Climate Change
LFL--Lower Flammability Limit
NAAQS--National Ambient Air Quality Standards
NAFEM--North American Association of Food Equipment Manufacturers
NAICS--North American Industrial Classification System
NARA--National Archives and Records Administration
NATE--North American Technician Excellence
NPRM--Notice of Proposed Rulemaking
NRDC--Natural Resources Defense Council
ODP--Ozone Depletion Potential
ODS--Ozone Depleting Substances
OMB--United States Office of Management and Budget
OSHA--United States Occupational Safety and Health Administration
PFAS--Perfluoroalkyl Substances, Polyfluoroalkyl Substances
PPM--Parts Per Million
PRA--Paperwork Reduction Act
PTAC--Packaged Terminal Air Conditioner
PTHP--Packaged Terminal Heat Pump
RCL--Refrigerant Concentration Limit
RCRA--Resource Conservation and Recovery Act
RFA--Regulatory Flexibility Act
RSES--Refrigeration Service Engineers Society
SDS--Safety Data Sheet
SIP--State Implementation Plan
SNAP--Significant New Alternatives Policy
TLV-TWA--Threshold Limit Value-Time-Weighted Average
TFA--Trifluoroacetic Acid
TSCA--Toxic Substances Control Act
TWA--Time Weighted Average
UL--Underwriters Laboratories Inc
UMRA--Unfunded Mandates Reform Act
VOC--Volatile Organic Compounds
VRF--Variable Refrigerant Flow
VSLS--Very Short-Lived Substances
WEEL--Workplace Environmental Exposure Limit
WMO--World Meteorological Organization
WSHP--Water-Source Heat Pump

II. What is EPA finalizing in this action?

A. Retail Food Refrigeration--Listing of R-448A, R-449A and R-449B as 
Acceptable, Subject to Narrowed Use Limits, for Retail Food 
Refrigeration--Medium-Temperature Stand-Alone Units (New)

    As proposed, EPA is listing R-448A, R-449A, and R-449B as 
acceptable, subject to narrowed use limits, in new equipment only for 
new medium-temperature stand-alone units in retail food refrigeration 
(hereafter, ``new medium-temperature stand-alone units'').\4\ As 
explained below, we have revised the regulatory text from the 2020 NPRM 
to indicate that failure to comply with the Americans with Disabilities 
Act (ADA) requirements is not the only reason other alternatives can be 
deemed infeasible under the narrowed use limit.
---------------------------------------------------------------------------

    \4\ EPA previously divided the retail food refrigeration end-use 
into separate categories, including stand-alone equipment (76 FR 
78832, December 20, 2011). The Agency further subdivided stand-alone 
equipment to distinguish between medium-temperature equipment, which 
maintains products above 32 [deg]F (0 [deg]C), and low-temperature 
equipment, which maintains products at or below 32 [deg]F (0 [deg]C) 
(80 FR 42870, July 20, 2015).

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

[[Page 24447]]

1. Background on Retail Food Refrigeration--Medium-Temperature Stand-
Alone Units (New)
    Retail food refrigeration is characterized by storing and 
displaying, generally for sale, food and beverages at different 
temperatures for different products (e.g., chilled and frozen food). 
Stand-alone units in retail food refrigeration (hereafter, ``stand-
alone units'') consist of refrigerators, freezers, and reach-in coolers 
(either open or with doors) where all refrigeration components are 
integrated and, for the smallest types, the refrigeration circuit is 
entirely brazed or welded. For purposes of the SNAP program, medium-
temperature stand-alone units maintain a temperature above 32 [deg]F (0 
[deg]C). For further background on this end-use, see the 2020 NPRM at 
85 FR 35877.
    In the 2015 Rule, EPA changed the listing of 31 refrigerants \5\ 
from acceptable to unacceptable for new medium temperature stand-alone 
units. At that time, EPA indicated that it believed that other 
alternatives that posed lower risk were available for this end use. 
After the 2015 Rule, as part of a petition from the Air-Conditioning, 
Heating, and Refrigeration Institute (AHRI),\6\ described in section 3 
below, EPA received information indicating that manufacturers were 
unable to design certain types of medium-temperature stand-alone 
equipment with the available acceptable alternatives, and that certain 
equipment configurations would require significantly larger 
refrigeration equipment that could jeopardize compliance with the ADA 
for those types of equipment.
---------------------------------------------------------------------------

    \5\ Specifically, FOR12A, FOR12B, HFC-134a, HFC-227ea, KDD6, 
R125/290/134a/600a (55.0/1.0/42.5/1.5), R-404A, R-407A, R-407B, R-
407C, R-407F, R-410A, R-410B, R-417A, R-421A, R-421B, R-422A, R-
422B, R-422C, R-422D, R-424A, R-426A, R-428A, R-434A, R-437A, R-
438A, R-507A, RS-24 (2002 formulation), RS-44 (2003 formulation), 
SP34E, and THR-03.
    \6\ AHRI, 2017. Petition Requesting EPA SNAP Approval of R-448A/
449A/449B for Medium Temperature, Stand-Alone Retail Food 
Refrigeration Equipment. Submitted March 20, 2017.
---------------------------------------------------------------------------

2. What are R-448A, R-449A and R-449B and how do they compare to other 
refrigerants in the same end-use?
    R-448A, marketed under the trade name Solstice[supreg] N-40, is a 
weighted blend of 26 percent HFC-32,\7\ which is also known as 
difluoromethane (Chemical Abstracts Service Registry Number [CAS Reg. 
No.] 75-10-5); 26 percent HFC-125, which is also known as 1,1,1,2,2-
pentafluoroethane (CAS Reg. No. 354-33-6); 21 percent HFC-134a, which 
is also known as 1,1,1,2-tetrafluoroethane (CAS Reg. No. 811-97-2); 20 
percent HFO-1234yf, which is also known as 2,3,3,3-tetrafluoroprop-1-
ene (CAS Reg. No. 754-12-1); and seven percent HFO-1234ze(E), which is 
also known as trans-1,3,3,3-tetrafluoroprop-1-ene (CAS Reg. No. 29118-
24-9). R-449A, marketed under the trade name Opteon[supreg] XP 40, is a 
weighted blend of 24.3 percent HFC-32, 24.7 percent HFC-125, 25.7 
percent HFC-134a, and 25.3 percent HFO-1234yf. R-449B, marketed under 
the trade name Forane[supreg] 449B, is a weighted blend of 25.2 percent 
HFC-32, 24.3 percent HFC-125, 27.3 percent HFC-134a, and 23.2 percent 
HFO-1234yf.
---------------------------------------------------------------------------

    \7\ In this final rule, we refer to this refrigerant with the 
technical prefix (i.e., R-32) and with the composition designating 
prefix (i.e., HFC-32) interchangeably.
---------------------------------------------------------------------------

    EPA previously listed R-448A, R-449A, and R-449B as acceptable 
refrigerants in a number of other refrigeration and air conditioning 
end-uses, including other retail food refrigeration end-use categories 
(e.g., 80 FR 42053, July 16, 2015; 81 FR 70029, October 11, 2016; 82 FR 
33809, July 21, 2017; 83 FR 50026, October 4, 2018; 84 FR 64765, 
November 25, 2019).
    Redacted submissions and supporting documentation for R-448A, R-
449A, and R-449B are provided in the docket for this rule (EPA-HQ-OAR-
2019-0698) at https://www.regulations.gov. EPA performed an assessment 
to examine the health and environmental risks of each of these 
substitutes, and these assessments are also available in the docket for 
this rule.8 9 10
---------------------------------------------------------------------------

    \8\ ICF, 2020a. Risk Screen on Substitutes in Retail Food 
Refrigeration (Medium-temperature Stand-alone Units) (New 
Equipment); Substitute: R-448A.
    \9\ ICF, 2020b. Risk Screen on Substitutes in Retail Food 
Refrigeration (Medium-temperature Stand-alone Units) (New 
Equipment); Substitute: R-449A.
    \10\ ICF, 2020c. Risk Screen on Substitutes in Retail Food 
Refrigeration (Medium-temperature Stand-alone Units) (New 
Equipment); Substitute: R-449B.
---------------------------------------------------------------------------

    Environmental information: R-448A, R-449A, and R-449B have an ozone 
depletion potential (ODP) of zero.\11\ Their components, HFC-32, HFC-
125, HFC-134a, HFO-1234yf, and in the case of R-448A, HFO-1234ze(E), 
have global warming potentials (GWPs) of 675; 3,500; 1,430; \12\ less 
than one to four; 13 14 15 and less than one to six; 
16 17 respectively. If these values are weighted by mass 
percentage, then R-448A, R-449A, and R-449B have GWPs of about 1,390, 
1,400, and 1,410, respectively. HFC-32 (CAS Reg. No. 75-10-5), HFC-125 
(CAS Reg. No. 354-33-6), HFC-134a (CAS Reg. No. 811-97-2), HFO-1234yf 
(CAS Reg. No. 754-12-1) and HFO-1234ze(E) (CAS Reg. No. 29118-24-9)--
the components of R-448A, R-449A, and R-449B--are excluded from the 
definition of volatile organic compounds (VOC) under CAA regulations 
(see 40 CFR 51.100(s)) addressing the development of state 
implementation plans (SIPs) to attain and maintain the national ambient 
air quality standards (NAAQS).
---------------------------------------------------------------------------

    \11\ If a compound contains no chlorine, bromine, or iodine, or 
if it is a solid under conditions of use, its ODP is generally 
considered to be zero. Unless otherwise stated, all non-zero ODPs in 
this document are from EPA's regulations at appendix A to subpart A 
of 40 CFR part 82.
    \12\ Unless otherwise specified, GWP values are from IPCC (2007) 
Climate Change 2007: The Physical Science Basis. Contribution of 
Working Group I to the Fourth Assessment Report of the 
Intergovernmental Panel on Climate Change. S. Solomon, D. Qin, M. 
Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor and H.L. Miller 
(eds.). Cambridge University Press. Cambridge, United Kingdom 996 
pp.
    \13\ Nielsen et al., 2007. Nielsen, O.J., Javadi, M.S., Sulbaek 
Andersen, M.P., Hurley, M.D., Wallington, T.J., Singh, R. 2007. 
Atmospheric chemistry of CF3CF=CH2: Kinetics 
and mechanisms of gas-phase reactions with Cl atoms, OH radicals, 
and O3. Chemical Physics Letters 439, 18-22. Available 
online at http://www.cogci.dk/network/OJN_174_CF3CF=CH2.pdf.
    \14\ Hodnebrog [Oslash]. et al., 2013. Hodnebrog [Oslash]., 
Etminan, M., Fuglestvedt, J.S., Marston, G., Myhre, G., Nielsen, 
C.J., Shine, K.P., Wallington, T.J.: Global Warming Potentials and 
Radiative Efficiencies of Halocarbons and Related Compounds: A 
Comprehensive Review, Reviews of Geophysics, 51, 300-378, 
doi:10.1002/rog.20013, 2013.
    \15\ WMO (World Meteorological Organization), Scientific 
Assessment of Ozone Depletion: 2018, Global Ozone Research and 
Monitoring Project-- Report No. 58, 588 pp., Geneva, Switzerland, 
2018. Available at: https://ozone.unep.org/sites/default/files/2019-05/SAP-2018-Assessment-report.pdf. In this action, the 100-year GWP 
values are used.
    \16\ Ibid.
    \17\ Hodnebrog [Oslash]. et al., 2013 and Javadi et al., 2008. 
M.S. Javadi, R. S[oslash]ndergaard, O.J. Nielsen, M.D. Hurley, and 
T.J. Wellington, 2008. Atmospheric chemistry of trans-
CF3CH=CHF: Products and mechanisms of hydroxyl radical 
and chlorine atom-initiated oxidation. Atmospheric Chemistry and 
Physics Discussions 8, 1069-1088, 2008.
---------------------------------------------------------------------------

    Knowingly venting or otherwise knowingly releasing or disposing of 
these refrigerant blends in the course of maintaining, servicing, 
repairing or disposing of an appliance or industrial process 
refrigeration is prohibited as provided in section 608(c)(2) of the CAA 
and EPA's regulations at 40 CFR 82.154(a)(1).
    Flammability information: R-448A, R-449A, and R-449B as formulated, 
and even considering the worst-case fractionation for flammability, are 
not flammable.
    Toxicity and exposure data: Potential health effects of exposure to 
these substitutes include drowsiness or dizziness. The substitutes may 
also irritate the skin or eyes or cause frostbite. At sufficiently high 
concentrations, the substitutes may cause irregular heartbeat. The 
substitutes could cause asphyxiation if

[[Page 24448]]

air is displaced by vapors in a confined space. These potential health 
effects are common to many refrigerants.
    The American Industrial Hygiene Association (AIHA) has established 
workplace environmental exposure limits (WEELs) of 1,000 parts per 
million (ppm) as an eight hour time-weighted average (8-hr TWA) for 
HFC-32, HFC-125, and HFC-134a, and 500 ppm as an 8-hr TWA for HFO-
1234yf, the components of R-448A, R-449A, and R-449B; and 800 ppm as an 
8-hr TWA for HFO-1234ze(E), also a component of R-448A. The 
manufacturer of R-448A recommends an acceptable exposure limit (AEL) of 
890 ppm on an 8-hr TWA for the blend. The manufacturer of R-449A 
recommends an AEL of 830 ppm on an 8-hr TWA for the blend. The 
manufacturer of R-449B recommends an AEL of 865 ppm on an 8-hr TWA for 
the blend. EPA anticipates that users will be able to meet the AIHA 
WEELs and manufacturers' AELs and address potential health risks by 
following requirements and recommendations in the manufacturers' safety 
data sheets (SDS), in American Society of Heating, Refrigerating, and 
Air-Conditioning Engineers (ASHRAE) Standard 15, and other safety 
precautions common to the refrigeration and air conditioning industry.
    Comparison to other substitutes in this end-use: R-448A, R-449A, 
and R-449B have ODPs of zero, comparable to or lower than other 
acceptable substitutes in this end-use, with ODPs ranging from zero to 
0.098.
    R-448A's GWP of 1,390, R-449A's GWP of 1,400, and R-449B's GWP of 
1,410 are higher than those of other acceptable substitutes for retail 
food refrigeration--medium-temperature stand-alone units (new), 
including ammonia absorption, R-744, R-450A, and R-513A with GWPs 
ranging from zero to 630.
    Information regarding the flammability and toxicity of other 
available alternatives are provided in the listing decisions previously 
made (see https://www.epa.gov/snap/substitutes-stand-alone-equipment). 
Flammability and toxicity risks for R-448A, R-449A, and R-449B are 
comparable to or lower than flammability and toxicity risks of other 
available substitutes in the same end-use. Toxicity risks can be 
minimized by use consistent with ASHRAE Standard 15 and other industry 
standards, recommendations in the manufacturers' SDS, and other safety 
precautions common in the refrigeration and air conditioning industry.
    Although R-448A, R-449A, and R-449B present a higher overall risk 
to human health and the environment than other acceptable alternatives 
in this end-use category based on significantly higher GWPs than other 
available alternatives, with GWPs ranging from zero (ammonia in a 
secondary loop) to 630 (R-513A), as provided below, EPA has determined 
that other alternatives may not be available for certain uses and users 
of medium-temperature stand-alone equipment. Thus, EPA is listing these 
substitutes as acceptable subject to narrowed use limits in this end-
use. Under the SNAP program, when using an alternative listed as 
acceptable with narrowed use limits, users, including manufacturers, of 
new medium-temperature stand-alone equipment will need to ascertain 
that the other alternatives are not technically feasible before using 
R-448A, R-449A, or R-449B in such equipment.\18\ Consistent with 
existing SNAP regulations, they must document the results of their 
evaluation that showed the other alternatives to be not technically 
feasible and maintain that documentation in their files. This 
documentation, which does not need to be submitted to EPA unless 
requested to demonstrate compliance, ``shall include descriptions of 
substitutes examined and rejected, processes or products in which the 
substitute is needed, reason for rejection of other alternatives, e.g., 
performance, technical or safety standards, and the anticipated date 
other substitutes will be available and projected time for switching to 
other available substitutes.'' (40 CFR 82.180(b)(3)).\19\
---------------------------------------------------------------------------

    \18\ As noted in the proposal, under the SNAP regulations the 
definition of ``use'' includes ``but [is] not limited to use in a 
manufacturing process or product, in consumption by the end-user, or 
in intermediate uses, such as formulation or packaging for other 
subsequent uses;'' hence, this definition includes the manufacture 
of a product pre-charged with a particular refrigerant. (40 CFR 
82.172).
    \19\ In the regulatory text of the 2020 NPRM, the description of 
the information to document was included in the ``Further 
information'' column. Because this information is required under the 
existing SNAP regulations at 40 CFR 82.180(b)(3), we have listed 
this in the ``Narrowed use limits'' column in this final action.
---------------------------------------------------------------------------

3. AHRI Petition
    AHRI petitioned EPA under CAA section 612(d) to add R-448A, R-449A, 
and R-449B to the list of acceptable substitutes for new and retrofit 
medium-temperature stand-alone units. See 40 CFR 82.184 for further 
information regarding petitions under the SNAP program. EPA and AHRI 
exchanged information related to this petition between March 2017 and 
November 2018. Information received as part of this petition is 
relevant to this listing, and EPA's action in this rulemaking may be 
considered responsive to certain aspects of this petition, although EPA 
is not taking formal action on the petition in this rulemaking. We 
describe the contents of the petition, including elements that we are 
not considering in this action, in detail in the 2020 NPRM, and the 
petition is available in the docket for this rulemaking.
4. What is EPA's final listing decision for R-448A, R-449A and R-449B?
    EPA is listing R-448A, R-449A, and R-449B as acceptable, subject to 
narrowed use limits, for new medium-temperature stand-alone units in 
this final rule.
    EPA understands that to construct certain medium-temperature stand-
alone units with the available acceptable refrigerants would require 
significantly larger components, or the addition of multiple 
refrigeration systems, which may lead to redesigning the units in such 
a manner that could be inconsistent with the ADA requirements. AHRI's 
petition specifically pointed to R-448A, R-449A, and R-449B as 
refrigerants that would, on the contrary, be feasible in such equipment 
and requested that those refrigerants be added to the list of 
acceptable refrigerants for new medium-temperature stand-alone units.
    Users under SNAP, including manufacturers, using a substitute 
listed as acceptable, subject to narrowed use limits, must ascertain 
that other substitutes or alternatives are not technically feasible. As 
explained in the initial SNAP rulemaking (59 FR 13063, March 18, 1994), 
under the narrowed use limit, ``[u]sers are expected to undertake a 
thorough technical investigation of alternatives before implementing 
the otherwise restricted substitute'' (i.e., R-448A, R-449A or R-449B 
for this rule). Further, ``[t]he Agency expects users to contact 
vendors of alternatives to explore with experts whether or not other 
acceptable substitutes are technically feasible for the process, 
product or system in question'' (i.e., in new medium-temperature stand-
alone units for this rule) to the otherwise restricted substitute. The 
initial SNAP rule also explained that ``[a]lthough users are not 
required to report the results of their investigations to EPA, 
companies must document these results, and retain them in company files 
for the purpose of demonstrating compliance'' for up to five years 
after the date of creation of the records. This information includes 
descriptions of:

[[Page 24449]]

     Process or product in which the substitute is needed;
     Substitutes examined and rejected;
     Reason for rejection of other alternatives, e.g., 
performance, technical or safety standards; and/or
     Anticipated date other substitutes will be available and 
projected time for switching.
    An example of a viable explanation under a narrowed use limit in 
this circumstance could include information such as a market analysis 
of the components for other alternatives that indicate a lack of 
availability in the required sizes or with required features, or design 
diagrams that indicate excessive loss of refrigerated volumes or 
failure to meet ADA requirements. As explained below, we have revised 
the regulatory text from the 2020 NPRM to indicate that failure to 
comply with ADA requirements is not the only reason the other 
alternatives can be deemed infeasible under the narrowed use limit.
5. How is EPA responding to comments on retail food refrigeration--
medium-temperature stand-alone units?
    EPA received comments from organizations with various interests in 
retail food refrigeration regarding the proposed listing of R-448A, R-
449A and R-449B. Most commenters supported the proposed listings, 
although some supported listing these refrigerants as acceptable 
without narrowed use limits and others did not support the listing at 
all. Other commenters addressed the environmental impacts of the 
proposed listing of R-448A, R-449A and R-449B and the proposed narrowed 
use limits. Other comments unrelated to these listings and beyond the 
scope of this final action are addressed in section III.
    Commenters on these proposed listings were AHRI, the Alliance for 
Responsible Atmospheric Policy (the Alliance), North American 
Association of Food Equipment Manufacturers (NAFEM), and Heating, Air-
conditioning, & Refrigeration Distributors International (HARDI), four 
industry organizations; Chemours and Honeywell, two chemical producers; 
Hussmann Corporation, Johnson Controls, Lennox International Inc., 
Parker Hannifin Corporation, and Rheem Manufacturing Company, five 
equipment manufacturers; and the Natural Resource Defense Council 
(NRDC) and the Environmental Investigation Agency (EIA), two 
environmental organizations.
    We have grouped comments together and responded to the issues 
raised by the comments in the sections that follow.
a. Support Listings
    Comment: HARDI indicated that it ``supports the overall effort to 
phase down the use of HFC refrigerants'' and held that the listing of 
R-448A, R-449A, and R-449B (and others discussed later in its comments) 
``is one part of a larger process in the industry's effort to phase 
down older refrigerants.'' Lennox International Inc. also supported the 
proposed listing of R-448A, R-449A, and R-449B for use in medium 
temperature stand-alone refrigeration applications indicating that 
``[t]hese refrigerants generally replace R404[A] and provide 
significant environmental benefits while providing the appropriate 
technology to meet the ongoing regulatory requirements.''
    Response: The Agency acknowledges HARDI's and Lennox's support for 
this proposed listing. After considering all the public comments on 
this proposal, we are finalizing this listing, as described in section 
II.A.
    Comment: Parker Hannifin Corporation's Sporlan division ``agrees 
with AHRI's positions and statements concerning this proposed listing, 
and [they] support it and the narrowed use limits as proposed.''
    Response: To the extent this comment refers to comments from the 
AHRI, we have responded separately. To the extent Sporlan is supporting 
the proposed listing including the narrowed use limits, we acknowledge 
this support. After considering all the public comments on this 
proposal, we are finalizing this listing, as described in section II.A.
b. Support Listings Without Narrowed Use Limits
i. Comparison to Other Acceptable SNAP Listings
    Comment: The Alliance, Chemours, Honeywell and Rheem supported 
finding R-448A, R-449A, and R-449B acceptable, but they did not support 
the proposal to make such listings subject to narrowed use limits. 
NAFEM also supported approval of R-448A, R-449A, and R-449B without use 
restrictions ``so that those refrigerants still can be allowed for 
critical applications.'' Noting that these blends are listed as 
acceptable for low temperature stand-alone equipment, Rheem commented 
that ``a common platform of low-GWP refrigerants is more beneficial to 
the installer and service personnel as well as for the manufacturer.''
    Response: In this final rule, EPA is including the narrowed use 
limits for these refrigerants. EPA explained why these alternatives 
posed higher risk to human health and the environment than other 
acceptable substitutes in this end-use in the proposal (85 FR 35879-
35880, June 12, 2020) and summarized those findings again above. In the 
proposal, EPA noted that the GWPs of these compounds, ranging from 
1,390 to 1,410, ``are higher than those of other acceptable substitutes 
for retail food refrigeration--medium-temperature stand-alone units 
(new)'' (85 FR 35878, June 12, 2020) and pointed to examples of such 
acceptable substitutes with lower GWPs and otherwise similar overall 
risk to human health and the environment. For those same reasons, EPA 
concludes in this final action that these alternatives pose higher risk 
to human health and the environment than other acceptable substitutes 
in this end-use. By finding these higher-GWP blends acceptable subject 
to narrowed use limits, EPA is allowing for these refrigerants to be 
used under SNAP as long as the requirements for the narrowed use limit 
have been met. Further, we note that because EPA evaluates the 
available or potentially available alternatives for different end-use 
categories separately, given that each intersection of an alternative 
and end-use category poses unique risk to human health and the 
environment, as well as unique technical challenges and requirements 
that must be met in order for a substitute to be available in a 
particular end-use or application, we would not necessarily list the 
same refrigerant as acceptable across multiple end-use or end-use 
categories. For example, in low temperature stand-alone equipment, EPA 
has listed a number of other refrigerants as acceptable with overall 
risk, including GWPs, similar to or greater than the overall risk, 
including GWPs, of R-448A, R-449A, and R-449B, unlike in medium 
temperature stand-alone equipment. To the extent industry stakeholders 
see a benefit for a single refrigerant for use across all their 
equipment, and find that the required analysis to use R-448A, R-449A, 
or R-449B under a narrowed use limit does not support such across-the-
board use, we note that there are already several alternatives that are 
listed acceptable for both medium and low temperature equipment that 
they can pursue.
    Comment: Chemours notes that R-448A, R-449A, and R-449B have been 
listed as acceptable in several other end-uses. They contend that ``EPA 
fails to provide a rational basis for treating R-448A, R-449A and R-
449B differently

[[Page 24450]]

in this proposed rule as opposed to past approvals.''
    Response: Since the inception of the SNAP program, alternatives are 
evaluated on an end-use by end-use (or in this case, an end-use 
category) basis. There is no reason to believe whether and how an 
alternative is listed in one end-use would be the same as a different 
end-use. In this case, as described above and in the proposal, EPA 
finds that, with other criteria being comparable, the GWP of R-448A, R-
449A, and R-449B, each of which has a GWP of approximately 1,400 that 
is higher compared to other acceptable alternatives in the medium 
temperature stand-alone equipment end-use, justifies the need for 
narrowed use limits. Other acceptable alternatives are available for 
this end-use which have GWPs of approximately 630 or lower, and some of 
which have already been implemented in equipment within this end-use 
category. EPA had not listed R-448A, R-449A, and R-449B as acceptable 
without restriction in this end-use before this final rule specifically 
because the higher GWPs indicate they pose a greater overall risk to 
human health and the environment. After receiving information 
indicating that manufacturers were unable to design certain types of 
medium-temperature stand-alone equipment with the available acceptable 
alternatives, we are finding the use of these high-GWP blends 
acceptable in this end-use consistent with the narrowed use limit 
established by this final rule.
    Comment: Chemours states that R-448A, R-449A, and R-449B have 
substantially lower GWPs compared with current refrigerants.
    Response: EPA understands Chemours' comment to refer to substitutes 
in existing equipment that have higher GWPs, such as HFC-134a, R-404A 
or R-507A, with GWPs of 1,430, 3,920 and 3,990, respectively. EPA 
changed the listing for these and certain other high-GWP refrigerants 
to unacceptable in stand-alone equipment and other end-uses in the 2015 
Rule. EPA compared the substitutes under consideration in this action 
with other available or potentially available substitutes and not with 
unacceptable substitutes which are prohibited under SNAP. While some 
acceptable alternatives for new medium temperature stand-alone 
equipment do have higher GWPs than the three refrigerant blends under 
consideration in this action, EPA notes that those refrigerants have an 
ODP being comprised in part of ozone-depleting chemicals, e.g., HCFCs. 
However, regulations promulgated under CAA section 605 phasing out the 
production and import of HCFCs also ban their use in new equipment. All 
acceptable non-ozone depleting alternatives for this end-use category 
have GWPs lower than R-448A, R-449A, and R-449B, in some cases 
significantly so (e.g., GWPs less than 10 compared to GWPs of 
approximately 1,400 for these three blends).
ii. Insufficient Justification for Narrowed Use Limits
    Comment: The Alliance stated that EPA ``does not offer 
justification why the [narrowed] use limits are necessary.'' Chemours 
says that ``EPA fails to provide any independent rationale supporting 
such [narrowed use limits] conditions'' and Honeywell added that ``the 
proposed rule offers no justification for such [narrowed] use limits 
and indeed they are not necessary.'' Honeywell contended that EPA did 
not explain the specific reasons why narrowed use limits are necessary. 
Johnson Controls requested EPA to add justification for the narrowed 
use limits.
    Response: EPA provided justification for the narrowed use limits in 
the proposal (85 FR 35879-35880, June 12, 2020). These alternatives 
pose higher risk to human health and the environment than other 
acceptable substitutes listed in this end-use. Relying on information 
submitted by AHRI in its petition to EPA, the proposal explained that 
while other acceptable alternatives were available for certain types of 
equipment within this end-use, the thermodynamic properties of other 
acceptable alternatives would require larger components and potentially 
lead to designs that would fail to comply with the ADA for certain 
equipment. For instance, in its comments, the Alliance quoted EPA 
statements from the proposal to this effect. EPA provided some examples 
of equipment within the medium-temperature stand-alone equipment 
category that have been manufactured with other acceptable alternatives 
that are available and for which there is no known conflict with the 
ADA requirements. Other commenters such as EIA added to this record. 
Hence, based on the information from AHRI and the evidence of existing, 
available equipment using acceptable refrigerants, EPA is concluding in 
this final action that within this end-use category, while some models 
can be manufactured using other acceptable alternatives, those 
alternatives might not be feasible for other models which could be 
manufactured with R-448A, R-449A, or R-449B. This conclusion warrants 
the narrowed use limit for these alternatives and conforms with the 
instances where listing with a narrowed use limit is justified as 
discussed in the original SNAP Rule (59 FR 13044, March 18, 1994) and 
codified in our regulations. Specifically, ``[e]ven though the Agency 
can restrict the use of a substitute based on the potential for adverse 
effects, it may be necessary to permit a narrowed range of use within a 
sector end-use because of the lack of alternatives for specialized 
applications'' (40 CFR 82.180(b)(3)). Here we find there may be 
specialized applications where the other acceptable alternatives are 
not feasible and use of R-448A, R-449A, or R-449B may be feasible. 
Thus, although we find R-448A, R-449A, or R-449B have the potential 
adverse effects due to their higher GWP compared to the other 
alternatives in this end-use category, we find that their use may be 
justified in certain equipment under a narrowed use limit.
iii. Clarification of Narrowed Use Limits
    Comment: Johnson Controls requests that EPA provide clarification 
regarding the narrowed use limits.
    Response: Because this comment was not specific on what needs to be 
clarified, no specific response is possible. However, we note that 
other comments had clearer requests for clarification on the narrowed 
use limits and we have addressed those in this final rule. These 
clarifications may also respond to Johnson Controls' request.
    Comment: Hussmann Corporation asked whether the narrowed use limit 
requirement to analyze and document that the other alternatives are 
infeasible before using R-448A, R-449A, or R-449B is to be performed 
for each model or a family of models. AHRI also asked whether the 
justification document would be required for each piece of equipment. 
Similarly, NAFEM stated ``EPA is unclear whether documentation may be 
kept by product number or for a group of similar products or group of 
alternatives.'' NAFEM also quoted the text in the ``Further 
information'' column on 85 FR 35893 and stated this was ambiguous in 
the level of detail being requested. They said that it was important to 
receive clarification that EPA's expectations of the documentation 
``will be flexible to recognize the different ways manufacturers may be 
able to categorize products, document by issue, or perhaps individual 
products based on a particular manufacturer's operations.''
    Response: EPA's SNAP regulations do not specify whether the 
analysis should be performed or documented for models

[[Page 24451]]

or families of models or group of alternatives. A manufacturer or other 
user wishing to avail itself of the flexibility provided by the 
narrowed use limit under the SNAP program is required to conduct the 
evaluation described in the SNAP regulations (see 40 CFR 82.180(b)(3)), 
document that the circumstances described in the those regulations have 
been met, and retain such documentation as required under those 
regulations. NAFEM said ``[t]here can be great variability in these 
products, with certain features perhaps customized for particular 
customers.'' Thus, a single analysis might not be able to adequately 
cover an entire family of models for these products or their customized 
design. EPA can envision scenarios where an analysis that shows other 
alternatives are infeasible could cover more than one model, however. 
For instance, models of similar size that differ in some 
characteristics--facings, shelf placements, etc.--without affecting the 
load, the required refrigeration equipment, and the determination that 
other alternatives are not feasible (e.g., due to ADA concerns) might 
be grouped together under a single analysis. Another example might 
include a model that is offered with doors and without. If the analysis 
addresses both types of equipment and concludes the with-doors version 
cannot use the other alternatives due to refrigeration equipment sizes 
leading to noncompliance with ADA, and the open-type version is of 
higher capacity and requires even larger refrigeration equipment to 
maintain the refrigeration load that has increased because the case is 
open to the surrounding air rather than enclosed by the doors, then the 
analysis could be applied to both models. In any such situation the 
analysis and any other documentation would need to address the factors 
listed in 40 CFR 82.180(b)(3), including listing the different products 
being evaluated, the reasons for rejection of other alternatives, the 
anticipated date other alternatives will be available, and the 
projected time for switching to available alternatives. If the analysis 
relies on a conclusion that the inability of one product to use the 
other acceptable alternatives also logically means the additional 
product(s) would not be able to use the other alternatives, the basis 
for that conclusion should be explained.
    Comment: Hussmann Corporation asked what would be required to show 
that other alternatives are not feasible, giving examples of testing 
results and calculations. Rheem similarly requested that EPA 
``[c]larify the burden of proof required for Narrowed Use Limits for R-
448A, R-449A, and R-449B'' asking ``[w]hat type of calculations or test 
results constitute sufficient proof of design unfeasibility.''
    Response: EPA does not dictate how a manufacturer or other user 
must prove that other alternatives are not feasible, as long as the 
requirements of the regulations regarding narrowed use limits are met. 
The regulations regarding narrowed use limits likewise give some leeway 
in how one determines the need for the otherwise restricted substitute. 
The regulations state that the user must ascertain that other 
alternatives are not technically feasible and that the documented 
analysis must include the other substitutes examined and rejected, the 
products where the alternatives (R-448A, R-449A, or R-449B) are needed, 
and the reason for rejecting the other alternatives. EPA responds to 
several comments, summarized below, that address the suitability of 
certain types of information that could be used and retained as part of 
the analysis required under the narrowed use limits.
    Comment: AHRI asked whether ``a description of the enabling 
regulations needed plus a period of time for preparation might be 
sufficient documentation'' to meet the requirements to use R-448A, R-
449A, or R-449B under the narrowed use limits. They provided as an 
example ``higher charge limits allowed for A2L refrigerant plus three 
years to prepare for the transition.''
    Response: The regulations pertaining to narrowed use limits require 
manufacturers or other users to include an anticipated time other 
alternatives might be available and a projected time for switching to 
other alternatives. Therefore, information such as what AHRI describes 
could be useful as part of addressing this portion of the analysis that 
must be performed and documented before relying on the flexibility 
under SNAP provided by the narrowed use limit that allows use of R-
448A, R-449A, or R-449B in appropriate circumstances. As described 
elsewhere, other information must also be included in this analysis. 
EPA does not generally believe, however, an open-ended time period 
(e.g., when ``enabling regulations'' are completed) would meet the 
intent of the requirement to address the anticipated time other 
alternatives might be available and the projected time for 
transitioning to other substitutes because that kind of general 
statement does not speak directly to the anticipated timing for 
availability or the projected timing for making the transition. 
Instead, EPA anticipates that manufacturers would use their technical 
expertise to describe the projected timing for these steps. For 
example, manufacturers could use their technical expertise to describe 
the regulations or standards that might need updating and how those 
items affect the choice of refrigerant, what steps must be taken to 
update the regulations and how long those steps are expected to take, 
and ultimately what steps are needed to implement the change in 
refrigerant in their equipment and whether those steps can commence 
even before the regulation and standard updates are final. On this last 
item of implementing the new refrigerant, EPA believes the additional 
three years in AHRI's comments could be reasonable for this type of 
equipment in appropriate circumstances. We note this is similar to the 
three years and five months found as an achievable transition time in 
previous regulations specifically for small medium temperature stand-
alone equipment (80 FR 42870, July 20, 2015).
iv. Grounds for Utilizing the Narrowed Use Limits
    Comment: The Alliance requested clarification on whether R-448A, R-
449A, and R-449B may be used in products that did conform with the ADA 
requirements but for other reasons the other alternatives are not able 
to be used. AHRI maintained that ADA compliance ``would not be the only 
reason that would allow for the use of these products'' and requested 
clarification of such.
    Response: The Alliance did not provide specifics on what these 
other reasons could be, so EPA is not addressing whether a given reason 
would or would not justify the use of R-448A, R-449A, or R-449B under 
the narrowed use limit. In considering this comment, EPA acknowledges 
that under the existing requirements in the SNAP regulations for 
utilizing a substitute under a narrowed use limit, it is possible that 
there are other reasons beside ADA requirements that the other 
alternatives could not be used and that inclusion of the phrase ``due 
to the inability to meet ADA requirements'' in the regulatory text as 
part of the narrowed use limit could unnecessarily limit users' ability 
to meet the requirements for using these substitutes under the narrowed 
use limit. Accordingly, EPA concludes that it is appropriate to clarify 
the text as the comment requests and is finalizing the regulatory text 
without this phrase included in the narrowed use limit. Thus, compared 
to the regulatory text of the proposed rule (85 FR 35892), under the 
``Narrowed use limits'' column, EPA in this final action is not 
including the phrase ``due to the inability to meet

[[Page 24452]]

ADA requirements'' but maintains the information in the ``Further 
information'' column that mentions ADA requirements as a possible 
reason for rejection of other alternatives. Under the final action, a 
manufacturer relying on ``other reasons'' for the narrowed use limit 
would need to document their analysis justifying this use, including 
the required information as described in the existing SNAP regulations, 
the same as those that found ADA requirements would be violated using 
the other alternatives must document their analysis.
    Comment: NAFEM noted the proposed rule pointed to the possible 
inability to comply with the ADA with the other alternatives as a 
justification to use R-448A, R-449A, and R-449B. NAFEM contended that 
other reasons may exist that would render the other alternatives not 
feasible for new medium temperature stand-alone equipment. They listed 
technical challenges such as ``[s]afety standards, user space 
constraints, energy efficiency requirements, and other performance 
considerations'' as reasons where use of R-448A, R-449A, or R-449B 
might be justifiable.
    Response: EPA agrees that there could be other reasons to determine 
that other alternatives are infeasible under the narrowed use limit. 
EPA concludes that in reviewing the AHRI petition and similar 
information such as that supplied in NAFEM's comments, including the 
September 1, 2015 letter attached to their comments, requesting R-448A 
and R-449A be acceptable for this equipment, the Agency considers ADA 
compliance to be one possible reason for the use of these high-GWP 
blends. That said, we cannot predict if all the other challenges listed 
by NAFEM, or any future challenges, might render the other alternatives 
technically infeasible for certain equipment in this end use, but 
acknowledge that such situations could arise. In this final rule, we 
clarify that compliance with the ADA is one example that a manufacturer 
might find makes the other alternatives technically infeasible, and 
thereby justify the use of R-448A, R-449A, or R-449B under the narrowed 
use limit, but that other reasons, if supported by the manufacturer's 
analysis under the SNAP regulations, might likewise justify use of 
these high-GWP blends under the narrowed use limit.
v. Narrowed Use Limits Are Burdensome
    Comment: Chemours was opposed to the narrowed use limits and stated 
that the narrowed use limits ``impose unnecessary burden on the 
industry's transition away from high global warming potential (`GWP') 
refrigerants.'' They stated that other alternatives have GWPs up to 65% 
higher than those of R-448A, R-449A, and R-449B and implied that 
approving these three blends without the narrowed use limit would 
support industry transition from high GWP refrigerants.
    Response: EPA disagrees that the narrowed use limits impose 
unnecessary burden. As described above, EPA finds that the narrowed use 
limits are necessary in this circumstance and without their inclusion, 
the Agency would not be able to find these three refrigerants 
acceptable for this specific end-use. These refrigerants present an 
overall greater risk to human health and the environment due to their 
higher GWP but for other factors have similar risks to other acceptable 
alternatives. All other zero-ODP alternatives that are acceptable 
within this end-use category have lower GWPs than the three found 
acceptable subject to narrowed use limits in this action. The listing 
of these three refrigerants subject to narrowed use limits under the 
SNAP regulations provides an option to use R-448A, R-449A, or R-449B, 
despite the higher GWP and higher overall risk to human health and the 
environment that these refrigerants pose compared to other acceptable 
refrigerants, when use of the other lower GWP alternatives is 
determined to be technically infeasible.
    Comment: Chemours contends that manufacturers should not be 
required to conduct the technical analysis to justify the use of R-
448A, R-449A, and R-449B under the narrowed use limit because AHRI has 
already completed this effort.
    Response: EPA disagrees with this comment. While EPA relies on 
information provided by AHRI to justify the listing of these high GWP 
blends, AHRI did not provide an analysis on any specific model that 
manufacturers offer and did not perform such analysis for all types of 
equipment that fall within this end-use category. Accordingly, the AHRI 
petition does not satisfy the requirements of 40 CFR 82.180(b)(3) for 
users who wish to avail themselves of the flexibility provided by the 
narrowed use limit to use R-448A, R-449A, and R-449B where other 
alternatives are found to be technically infeasible.
    Comment: Chemours points out that how a unit is placed within a 
store could impact aisle widths and compliance with ADA. Chemours says 
that manufacturers would need to know the layout of any store that 
would use a medium temperature stand-alone unit in order to justify the 
need for R-448A, R-449A, or R-449B as the only available alternatives 
that would comply with the ADA. They held that knowing the layout of 
each location where a unit is placed was an unreasonable burden. As 
such, they concluded that EPA should list these alternatives as 
acceptable without imposing narrowed use limits.
    Response: EPA disagrees that manufacturers would necessarily need 
to know the layout of the store to meet the requirements of the 
narrowed use limit. For example, information in the AHRI petition 
contended certain equipment models would not comply with the ADA using 
other available alternatives due to counter height requirements. If the 
required analysis shows that other alternatives are technically 
infeasible in such models due to counter height requirements and the 
ADA requirements, that could support a manufacturer's justification for 
reliance on the narrowed use limit in this equipment without knowledge 
of store layouts. In addition, as noted above, there may be 
justifications other than ADA compliance that could be used for relying 
on the narrowed use limit, as long as the requirements of 40 CFR 
82.180(b)(3) are met.
    Comment: Chemours also states that conducting a pre-manufacture 
analysis to justify the use of R-448A, R-449A, or R-449B based on ADA 
issues would not account for situations in which a unit was moved 
within a store or perhaps transferred to another retail location where 
a unit manufactured with another alternative would be feasible. They 
held that this possibility of a user moving a unit would make the 
narrowed use limit requirement to justify the use of the alternative 
ineffective and therefore argued for removing those narrowed use 
limits.
    Response: EPA understands that equipment may be moved or sold on a 
secondary market. However, the intent of this action is that for those 
availing themselves of the narrowed use limits provided in this rule 
conduct the necessary analysis and maintain the necessary 
documentation. Such documentation provides the justification to use 
these refrigerants under SNAP which otherwise would be unacceptable due 
to the higher risk to human health and the environment that they 
impose. If a chemical manufacturer or original equipment manufacturer 
is concerned with downstream users, they could consider options such as 
including relevant information about the narrowed use limit with their 
sales documentation. In addition, as noted above, there may be 
justifications other than ADA compliance that could be

[[Page 24453]]

used for relying on the narrowed use limit, as long as the requirements 
of 40 CFR 82.180(b)(3) are met.
    Comment: Chemours says the narrowed use limits ``unreasonably 
discourage the use of R-448A, R-449A and R-449B'' as compared to 
finding these refrigerants acceptable without use restrictions. They 
say that instead approving, without narrowed use limits, these 
refrigerants with a GWP lower than the currently used refrigerants 
would meet the Agency's duty to evaluate when an alternative would 
reduce overall risk to human health and the environment.
    Response: Although EPA lists refrigerants under CAA section 612, we 
do not encourage or discourage the use of any particular refrigerant. 
There are several alternatives listed as acceptable, some with use 
conditions, some, as in this final rule, with narrowed use limits, and 
some without use restrictions. In this final rule, we have evaluated 
these refrigerants under the SNAP program's comparative risk framework 
and concluded the narrowed use limits are appropriate because they 
present an overall greater risk to human health and the environment due 
to their higher GWP but for other factors have similar risks to other 
acceptable alternatives. Given that R-448A, R-449A and R-449B were not 
listed as acceptable for medium temperature stand-alone equipment prior 
to this final rule, the listing, even with a narrowed use limit, would 
not limit the use of these refrigerants. Rather, it could serve to 
increase the use of these refrigerants should manufacturers choose to 
adopt them based on their analyses.
    Comment: Chemours indicated that requirements of a narrowed use 
limit including the need for a documented transition plan to other 
alternatives are unworkable, as they require understanding when other 
substitutes will be available and a timeline for transitioning. They 
say users would not know what future regulations or requirements may 
exist, or what new alternatives may be introduced in the future, and 
would therefore need to speculate on these aspects in their analysis to 
justify the use of R-448A, R-449A, or R-449B. As such, Chemours says 
these refrigerants should be found acceptable without narrowed use 
limits.
    Response: EPA finalized regulations on narrowed use limits in 1994 
and has implemented such narrowed use limits in past decisions with no 
indication that such listings are unworkable. EPA further notes that 
the existing regulations, quoted in the proposal, require an 
``anticipated date other substitutes will be available and projected 
time for switching to other available substitutes.'' (emphasis added). 
Thus, EPA does not view these requirements as requiring manufacturers 
to provide a precise date of what will be available and when a 
transition will occur, but rather a reasonable assessment of such dates 
based on their technical expertise. It would be reasonable to assume 
chemical producers and suppliers could assist in this evaluation for 
users that choose to avail themselves of the flexibility offered by 
listing these refrigerants subject to narrowed use limits. Accordingly, 
EPA disagrees that it should find these refrigerants acceptable without 
narrowed use limits based on the uncertainties identified in this 
comment.
    Comment: Chemours further argues against including the narrowed use 
limits by indicating that the requirement to retain any analysis that 
supports the use of R-448A, R-449A, or R-449B in medium temperature 
stand-alone equipment is to support potential enforcement actions, and 
that developing such documentation including a transition plan is 
unreasonable ``when the Agency cannot concurrently provide clarity for 
this segment.''
    Response: EPA is not addressing enforcement in this final rule. 
However, we note that the existing regulations covering narrowed use 
limits, as quoted in the proposal, require a manufacturer to ``retain 
the results on file for purposes of demonstrating compliance.'' 
(emphasis added). As the requirement to retain the analysis is 
consistent with the existing SNAP regulations, which are not modified 
in this action, EPA disagrees with the suggestion that it should not 
finalize the narrowed use limits based on the points identified in this 
comment. The comment was unclear on what type of ``clarity for this 
segment'' Chemours is seeking; however, we have provided clarity for 
this end-use category including the listings to date of multiple 
alternatives as acceptable and the listing in this final rule providing 
flexibility to use R-448A, R-449A, and R-449B under SNAP subject to 
narrowed use limits.
c. Oppose Listings
i. Other Alternatives Available With Lower GWP
    Comment: The EIA and the NRDC opposed the listing of R-448A, R-449A 
and R-449B as acceptable subject to narrowed use limits. They indicated 
that because of these refrigerants' high GWP, they should not be listed 
for this type of equipment. EIA claimed that better alternatives, ``R-
513C, R-290, and R-600a'' exist and pointed to three different 
manufacturers that offer a wide range of equipment that meets ADA 
requirements and uses lower-GWP refrigerants. NRDC likewise noted SNAP-
acceptable alternatives for this end-use category include lower-GWP 
options such as ``ammonia vapor compression with secondary loop, carbon 
dioxide, R-290, R-441A, R-450A, R-513A, and isobutane'' and stated that 
``[s]everal companies are already producing and selling compliant 
products that use already-approved, low-GWP refrigerants'' without 
identifying those companies.
    Response: EPA agrees there is a variety of equipment using other 
acceptable alternatives with lower GWPs in medium temperature stand-
alone equipment and therefore did not propose to list the three 
refrigerants as acceptable but instead included a narrowed use limit to 
address specific circumstances that would render the other refrigerants 
as technically infeasible in particular applications within this end 
use. EPA is aware of such equipment using R-290, R-600a (isobutane), 
and R-744 (carbon dioxide). We also noted in the 2015 Rule that R-450A 
and R-513A were designed as HFC-134a replacements and therefore were 
potentially available for medium temperature stand-alone units that 
previously relied on HFC-134a. (We are not aware of a refrigerant being 
designated R-513C as noted by EIA and believe it may have been a 
typographical error for R-513A; regardless R-513C is not listed 
acceptable for this end-use category.) EPA also pointed to examples of 
medium temperature stand-alone equipment using lower-GWP refrigerants 
in our proposed rule. We further note that even manufacturers that do 
offer such equipment using the available alternatives may find such 
alternatives technically infeasible for some applications. Other 
information in the record elaborates on the limitations of the other 
acceptable alternatives in certain circumstances. For instance, in its 
comments on the 2020 NPRM, Hussmann Corporation stated ``[f]lammable 
and non-flammable refrigerant options currently approved by SNAP have 
less capacity and may require the use of multiple condensing units. 
This in turn creates additional heat rejection into stores, an increase 
in noise, store infrastructure issues that don't have the capacity for 
the electrical loads, increased design feasibility risks for the stand-
alone units due to increased piping, and increased

[[Page 24454]]

difficulty for servicing. Other refrigerant options may also require 
redesign due to the larger sizes of the condensing units which will 
limit the equipment installation due to narrow aisle and doorway 
openings.'' Accordingly, EPA concludes that the fact that other lower 
GWP refrigerants are listed as acceptable under SNAP for this end use 
does not mean that it should not list R-448A, R-449A and R-449B as 
acceptable subject to narrowed use limits.
ii. Adoption of Safety Standard UL 60335-2-89 2nd Ed.
    Comment: EIA notes that a proposal to modify UL 60335-2-89 is being 
considered. The proposal would allow up to 500 grams of R-290, or 13 
times the lower flammability limit (LFL) of other A3 refrigerants such 
as R-600a. EIA expects the revision to be complete in March 2021 and 
urges EPA to adopt it when available. EIA expects that adoption by EPA 
would further limit any need for R-448A, R-449A, or R-449B as it would 
allow feasible designs, e.g., requiring a single refrigeration circuit 
as opposed to a physically larger multi-circuit approach, over a 
broader range of equipment. With respect to the listing of R-448A, R-
449A, and R-449B under narrowed use limits, NRDC agreed that ``EPA 
should revisit this approval upon adoption of safety standard UL 60335-
2-89 2nd Ed. which will make it simpler to design compliant products 
with low-GWP refrigerants.'' Further, NRDC maintained that any 
rulemaking listing R-448A, R-449A or R-449B should only apply ``until 
products can be designed and sold to the specifications of the new UL 
standard.''
    Response: EPA acknowledges the ongoing process to update on UL 
60335-2-89. We also note that revisions to this standard were released 
for public comment in December 2020. As EIA notes, if we were to change 
use conditions that currently exist for R-290, R-600a and R-441A in 
stand-alone equipment (both medium and low temperature), we would 
undertake a rulemaking to do so. We cannot predict if or when we would 
do so before that standard is finalized and we can evaluate it to 
assess whether a change in use conditions is warranted; therefore, we 
have not limited the time that the listing of R-448A, R-449A, and R-
449B applies as NRDC suggests. That said, manufacturers availing 
themselves of the flexibilities offered by these SNAP listings subject 
to narrowed use limits could assess the status of this UL Standard and 
the possibility of adoption by EPA as part of their analyses that 
require an anticipated date other substitutes would be available and a 
projected time for switching.
d. Narrowed Use Limits Description
i. Narrowed Use Limits Should Be Temporary
    Comment: AHRI requested that R-448A, R-449A, and R-449B be listed 
as acceptable without narrowed use limits but felt that was only needed 
``until additional alternatives become available.''
    Response: To the extent that this comment suggests that R-448A, R-
449A, and R-449B may not be needed in the future, EPA agrees. Even if 
the current acceptable refrigerants are not currently feasible in this 
equipment, additional alternatives being investigated, if added to the 
list of acceptable substitutes, may take the place of these high-GWP 
blends. As explained above, should additional alternatives become 
available in the future, or use conditions of existing alternatives 
change in the future, a manufacturer using R-448A, R-449A, or R-449B 
under the narrowed use limit may need to consider the implications of 
such a change for its future use of R-448A, R-449A, or R-449B under the 
narrowed use limits for new medium temperature stand-alone equipment.
ii. Scope of Narrowed Use Limits
    Comment: NAFEM stated that the proposal to list R-448A, R-449A, and 
R-449B as acceptable subject to narrowed use limits ``is too narrowly 
defined and there should be other circumstances under which these 
refrigerants can be used for medium temperature applications.'' NAFEM 
pointed out that their member companies produce a wide range of 
equipment types and held that some of these do not fit neatly into 
EPA's end-use category of medium temperature stand-alone equipment and 
requested ``EPA to expand the product uses in which R-448A, R-449A, and 
R-449B may be used.'' NRDC however felt that should EPA list these 
refrigerants acceptable subject to narrowed use limits--which NRDC did 
not support--EPA should limit the listing ``to only specific product 
subtypes for which no alternatives are currently or potentially 
available.''
    Response: EPA has previously listed R-448A, R-449A, and R-449B as 
acceptable under several end-uses, some of which may operate at medium 
temperature, including supermarket systems, refrigerated transport, 
cold storage, refrigerated food processing and dispensing equipment, 
and others. We expect that some NAFEM members manufacture equipment 
under these end-uses; however, the comment is unclear as to whether 
NAFEM is requesting EPA ``to expand the product uses'' for these other 
end-uses where R-448A, R-449A, and R-449B are already listed as 
acceptable. To the extent NAFEM is referring to a broader list of 
circumstances in medium-temperature stand-alone equipment only, the 
specific types of such equipment were not defined, and thus EPA cannot 
judge whether they fit in the subject end-use category or another end-
use or if the end-use category might be further broken down into 
separate end-use subcategories. Accordingly, EPA is not expanding the 
product uses in which R-448A, R-449A, and R-449B may be used in this 
final rule. Likewise, NRDC did not specifically list the product 
subtypes in their comments, except to mention that more equipment could 
feasibly use lower GWP refrigerants in the future should EPA adopt 
revised use conditions for certain acceptable refrigerants based on a 
UL standard under development. Because information was not presented 
that would allow EPA to distinguish the product types within the 
medium-temperature stand-alone equipment end-use category that are and 
are not feasible with the acceptable alternatives, EPA is not limiting 
or expanding the narrowed use limits beyond new medium-temperature 
stand-alone equipment as proposed. As discussed in other responses, 
should additional alternatives be listed in this end-use category, a 
manufacturer utilizing R-448A, R-449A, or R-449B under the narrowed use 
limits may need to consider the implications of such a change for its 
future use of R-448A, R-449A, or R-449B under the narrowed use limits 
for new medium temperature stand-alone equipment.
iii. Routinely Submit Narrowed Use Limits Information
    Comment: Notwithstanding their argument against the listing, NRDC 
urged that if R-448A, R-449A, and R-449B were listed for this 
equipment, EPA should ``require that users of these three blends 
actively and periodically submit to EPA the specified required 
information under the narrowed use limits.''
    Response: Regulations for listing alternatives subject to narrowed 
use limits were established in the original SNAP rule (59 FR 13044, 
March 18, 1994) and were not reopened in the 2020 NPRM. The 1994 final 
regulations do not require or provide for users to submit their 
analysis, except when requested to demonstrate compliance.

[[Page 24455]]

To the extent the comment is suggesting that EPA should add a separate 
submission requirement for this particular listing, EPA is not 
establishing such a requirement because doing so would be inconsistent 
with the requirements of narrowed use limits that have existed for 27 
years and as indicated in this document and the proposal, EPA's 
intention is to maintain consistency with those existing requirements. 
If EPA decides in the future that additional reporting may be needed 
under narrowed use limits, either in general or for specific 
alternatives so listed, we can consider any relevant changes and if any 
revisions to this final rule should be proposed.
e. Approve for Retrofits
    Comment: Chemours requests that the Agency list R-448A, R-449A, and 
R-449B as acceptable for retrofits of medium temperature stand-alone 
equipment.
    Response: EPA has consistently viewed refrigerant listings for new 
equipment and for retrofitting existing equipment separately, as the 
overall risk to human health and the environment differs depending on 
whether equipment is newly manufactured (for this equipment, in a 
factory environment) compared to retrofitted (e.g., in the field or at 
a service center). We appreciate Chemours' comments; however, we did 
not propose the use of R-448A, R-449A, and R-449B in retrofits. There 
is not enough information in the record to make a determination for 
retrofits of this equipment in this rule, but we will take the 
suggestion under advisement for potential future listings.
f. Request for Cost-Benefit Analysis
    Comment: NAFEM ``encourages EPA to consider a benefit-cost analysis 
before finalizing this rulemaking.''
    Response: The listing of R-448A, R-449A, and R-449B as acceptable 
subject to narrowed use limits imposes no costs compared to the 
previous state where such refrigerants were not listed as acceptable 
for the subject end-use category. Instead, this final rule allows these 
three refrigerants to be used in instances where they were not allowed 
before and thus provides additional flexibilities under SNAP that 
manufacturers may choose to pursue. While there may be costs borne by 
those pursuing these refrigerants, it is a manufacturer's decision 
whether to pursue these alternatives and not a requirement that EPA is 
imposing on the manufacturer.

B. Residential and Light Commercial Air Conditioning and Heat Pumps--
Listing of R-452B, R-454A, R-454B, R-454C, and R-457A as Acceptable, 
Subject to Use Conditions, for Use in Residential and Light Commercial 
Air Conditioning and Heat Pumps End-Use for New Equipment; and R-32 as 
Acceptable, Subject to Use Conditions, for Use in Residential and Light 
Commercial Air Conditioning and Heat Pumps--Equipment Other Than Self-
Contained Room Air Conditioners for New Equipment

    As proposed, EPA is listing R-452B, R-454A, R-454B, R-454C, and R-
457A (hereafter called ``the five refrigerant blends'') as acceptable 
subject to use conditions as substitutes in residential and light 
commercial air conditioning and heat pumps for both self-contained and 
split systems, and R-32 as acceptable subject to use conditions in 
residential and light commercial air conditioning and heat pumps for 
split systems and for specific types of self-contained systems that are 
part of the residential and light commercial air conditioning and heat 
pump end-use but for which R-32 has not been previously listed.
    We note references to hydrocarbons mistakenly included in the 
``Further information'' column of the regulatory text in the 2020 NPRM 
are not included in this final rule. Also, in the 2020 NPRM we used the 
term ``mildly flammable'' in the ``Further information'' column of the 
regulatory text. Based on comments received, we have changed that term 
to ``flammable.'' \20\ Finally, we note that where the use requirement 
for red markings appeared in regulatory text of the 2020 NRPM, we 
indicated initially that it must be applied to ``pipes, hoses, or other 
devices through which the refrigerant passes.'' In this final action we 
are adding ``service ports'' there to be consistent with the sentence 
that follows. We offer clarification on this requirement below.
---------------------------------------------------------------------------

    \20\ In the NPRM, EPA used the term ``mildly flammable'' to 
describe A2L refrigerants. Based on comment as explained below, this 
is not the correct term used in ASHRAE Standard 34 and hence it has 
been revised throughout this final rule.
---------------------------------------------------------------------------

1. What use conditions is EPA finalizing?
    EPA is finalizing the use conditions as proposed, except for a 
revision, explained in subsections II.B.1.b and II.B.5.a below, to what 
constitutes ``new'' equipment. The use conditions were proposed and are 
finalized as a means to reduce the risk that exists when using 
flammable refrigerants. EPA has adopted similar use conditions in the 
past when listing flammable refrigerants acceptable, including the 
listing of HFC-32 for some of the equipment types that are included in 
the listing of the five refrigerant blends in this final rule (e.g., 76 
FR 78832, December 20, 2011; 80 FR 19454, April 10, 2015). Further 
discussion of these use conditions is in section 5 below.
    Under this listing, use of these refrigerants under the SNAP 
program requires adhering to all of the following use conditions:
a. UL Standard
    These refrigerants may be used only in AC equipment, both self-
contained equipment and split-systems, that meet all requirements 
listed in the 3rd edition, dated November 1, 2019, of UL Standard 
60335-2-40, ``Standard for Safety for Household And Similar Electrical 
Appliances--Safety--Part 2-40: Particular Requirements for Electrical 
Heat Pumps, Air Conditioners and Dehumidifiers'' (UL Standard).\21\ The 
UL Standard contains requirements for the types of equipment covered 
here, including testing, charge sizes, ventilation, usage space 
requirements, and certain hazard warnings and markings, among other 
topics. In cases where this final rule includes requirements more 
stringent than those of UL Standard 60335-2-40, the appliance will need 
to meet the requirements of this final rule in place of the 
requirements in the UL Standard. See section II.B.5 below for further 
discussion on the requirements of this UL Standard that EPA is 
incorporating by reference.
---------------------------------------------------------------------------

    \21\ All references to UL Standard 60335-2-40 are to the third 
edition unless otherwise noted.
---------------------------------------------------------------------------

    EPA finds, as in past rules, that it is appropriate to reference 
consensus standards that set conditions to reduce risk. As in past 
listings of flammable refrigerants, we find that such standards have 
already gone through a development phase that incorporates the latest 
findings and research. Likewise, such standards have gone through a 
vetting and refinement process that provides the affected parties an 
opportunity to comment. For the U.S. stationary air conditioning and 
refrigeration industry, EPA sees UL standards in general as a 
pervasively used body of work to address risks and these standards are 
the most applicable and recognized by the U.S. market. Most, and likely 
nearly all, covered equipment in the U.S. is listed as complying with 
the appropriate UL standard. In this case, UL 60335-2-40 covers, with 
modifications, equipment

[[Page 24456]]

also covered by other UL standards previously finalized and 
incorporates the works of international standards setting bodies; 
specifically, the International Electrotechnical Commission (IEC) 
standard IEC 60335-2-40 was used in the development of UL 60335-2-40.
b. New Equipment Only
    These refrigerants are being listed under SNAP only for use in new 
equipment designed specifically and clearly identified for the 
refrigerant; i.e., none of these substitutes are being listed for use 
as a conversion or ``retrofit'' refrigerant for existing equipment. In 
the 2020 NPRM, we stated in a footnote that we intended ``new'' 
equipment to include a new compressor, evaporator, condenser and 
refrigerant tubing (85 FR 35884). Based on consideration of public 
comments on the 2020 NPRM, we conclude that existing tubing can be 
inspected and if suitable re-used and the system would still be 
considered ``new'' for the purpose of this final rule.
    Given the possible ignition sources that exist in equipment 
designed for non-flammable refrigerants, EPA finds that retrofitting 
such equipment to use flammable refrigerants presents additional risks 
not adequately addressed by this standard. This position is widely 
supported by the comments as described below.
c. Warning Labels
    The following markings, or the equivalent, must be provided in 
letters no less than 6.4 mm (\1/4\ inch) high and must be permanent:
    i. On the outside of the air conditioning equipment: ``WARNING--
Risk of Fire. Flammable Refrigerant Used. To Be Repaired Only By 
Trained Service Personnel. Do Not Puncture Refrigerant Tubing''
    ii. On the outside of the air conditioning equipment: ``WARNING--
Risk of Fire. Dispose of Properly In Accordance With Federal Or Local 
Regulations. Flammable Refrigerant Used''
    iii. On the inside of the air conditioning equipment near the 
compressor: ``WARNING--Risk of Fire. Flammable Refrigerant Used. 
Consult Repair Manual/Owner's Guide Before Attempting to Service This 
Product. All Safety Precautions Must be Followed''
    iv. For any equipment pre-charged at the factory, on the equipment 
packaging: ``WARNING--Risk of Fire due to Flammable Refrigerant Used. 
Follow Handling Instructions Carefully in Compliance with National 
Regulations''
    v. On the indoor unit \22\ near the nameplate:
---------------------------------------------------------------------------

    \22\ This labeling is required for split systems and self-
contained equipment alike.
---------------------------------------------------------------------------

    (a) At the top of the marking: ``Minimum Installation height, X m 
(W ft)''. This marking is only required if the similar marking is 
required by the UL Standard. The terms ``X'' and ``W'' shall be 
replaced by the numeric height as calculated per the UL Standard. Note 
that the formatting here is slightly different than the UL Standard; 
specifically, the height in Inch-Pound units is placed in parentheses 
and the word ``and'' has been replaced by the opening parenthesis.
    (b) Immediately below the warning label indicated in (a) above or 
at the top of the marking if (a) is not required: ``Minimum room area 
(operating or storage), Y m\2\ (Z ft\2\)''. The terms ``Y'' and ``Z'' 
shall be replaced by the numeric area as calculated per the UL 
Standard. Note that the formatting here is slightly different than the 
UL Standard; specifically, the area in Inch-Pound units is placed in 
parentheses and the word ``and'' has been replaced by the opening 
parenthesis.
    vi. For non-fixed equipment, including portable air conditioners, 
window air conditioners, packaged terminal air conditioners and 
packaged terminal heat pumps, on the outside of the product: 
``WARNING--Risk of Fire or Explosion--Store in a well-ventilated room 
without continuously operating flames or other potential ignition.''
    vii. For fixed equipment, including rooftop units and split air 
conditioners, ``WARNING--Risk of Fire--Auxiliary devices which may be 
ignition sources shall not be installed in the ductwork, other than 
auxiliary devices listed for use with the specific appliance. See 
instructions.''
    The text of these labels is nearly identical to those in UL 60335-
2-40, with slight modifications noted above. We highlight this 
difference above and repeat those labels whose text we have not changed 
here to emphasize the importance of including such labels and to 
provide the labels we are requiring in a single place. We find labels 
as one of two marking conventions (the other being red markings as 
explained in section II.B.1.d below) that combined will provide 
adequate warning of the presence of a flammable refrigerant to those 
who may come into contact with it in potentially dangerous quantities 
and situations (i.e., in concentrations above the LFL and in the 
presence of an ignition source).
    EPA believes that it would be difficult to see warning labels with 
the minimum lettering height requirement of \1/8\ inch provided in the 
UL Standard. Therefore, consistent with the use conditions in our 
previous rules listing flammable refrigerants, including HFC-32, 
acceptable subject ot use conditions (e.g., 76 FR 78832, December 20, 
2011; 80 FR 19454, April 10, 2015), the minimum height for lettering 
must be \1/4\ inch as opposed to \1/8\ inch, which will make it easier 
for technicians, consumers, retail storeowners, and emergency first 
responders to view the warning labels.
d. Markings
    Equipment must have distinguishing red (Pantone[supreg] Matching 
System (PMS) #185 or RAL 3020) color-coded hoses and piping to indicate 
use of a flammable refrigerant. The air conditioning equipment shall 
have marked service ports, pipes, hoses and other devices through which 
the equipment's refrigerant circuit is serviced. Markings shall extend 
at least 1 inch (25mm) and shall be replaced if removed. As noted in 
comments below, there were some questions of what this use condition 
requires; EPA clarifies this requirement as follows. For equipment that 
contain field-constructed parts (i.e., finished at the site where the 
installation occurs), the connections to be finished in the field shall 
be marked red as described. For equipment with service ports, the 
service ports and/or piping extending therefrom shall be marked red as 
described. We note equipment might fit both categories above and hence 
must have both sets of red markings. For self-contained equipment 
without service ports, the location the manufacturer recommends as the 
place to access the refrigerant circuit (e.g., process tube) shall be 
marked red as described.

[[Page 24457]]

    The reason to include red markings in combination with warning 
labels is noted above. EPA finds that when combined with labels, such 
markings will provide adequate warning of the presence of a flammable 
refrigerant to those who may come into contact with it in potentially 
dangerous quantities and situations (i.e., in concentrations above the 
LFL and in the presence of an ignition source). As in previous 
rulemakings on flammable refrigerants cited above, we conclude that the 
red markings will provide an additional warning for technicians, 
consumers, retail storeowners, first responders, and those disposing 
the appliance to understand that a flammable refrigerant is used and 
appropriate caution should be taken. Furthermore, the red markings, as 
with symbols required by the UL Standard, provide a more universally-
understood warning demarcation, which would be useful for those who may 
not be able to read or understand the English language labels.
    The regulatory text of our decisions for the end-uses discussed 
above appears in tables at the end of this document. This text will be 
codified in appendix W of 40 CFR part 82 subpart G. EPA notes that 
there may be other legal obligations pertaining to the manufacture, 
use, handling, and disposal of the refrigerants that are not included 
in the information listed in the tables (e.g., the CAA section 
608(c)(2) prohibition on knowingly venting or otherwise knowingly 
releasing or disposing of substitute refrigerants in the course of 
maintaining, servicing, repairing or disposing of an appliance or 
industrial process refrigeration, or Department of Transportation 
requirements for transport of flammable gases). Flammable refrigerants 
being recovered or otherwise disposed of from residential and light 
commercial air conditioning appliances are likely to be hazardous waste 
under the Resource Conservation and Recovery Act (RCRA) (see 40 CFR 
parts 260-270).
2. Background on Residential and Light Commercial Air Conditioning and 
Heat Pumps (New)
    The residential and light commercial air conditioning and heat 
pumps end-use includes equipment for cooling air in individual rooms, 
in single-family homes, and in small commercial buildings. This end-use 
includes both self-contained and split systems. For further background 
on this end-use, see the 2020 NPRM (85 FR 35881-35882).
3. What are the ASHRAE classifications for refrigerant flammability?
    The six refrigerants that we are listing in this final rule for 
residential and light commercial AC and heat pumps are all assigned a 
safety group classification of ``A2L'' by The American National 
Standards Institute/American Society of Heating, Refrigerating and Air 
Conditioning Engineers (ANSI/ASHRAE) Standard 34-2019. ASHRAE 
classifies Class A refrigerants as refrigerants for which toxicity has 
not been identified at concentrations less than or equal to 400 ppm by 
volume, based on data used to determine threshold limit value-time-
weighted average (TLV-TWA) or consistent indices. The flammability 
classification ``2L'' is given to refrigerants that, when tested, 
exhibit flame propagation, have a heat of combustion less than 19,000 
kJ/kg (8,169 BTU/lb), have an LFL greater than 0.10 kg/m\3\, and have a 
maximum burning velocity of 10 cm/s or lower when tested in dry air at 
73.4 [deg]F (23.0 [deg]C) and 14.7 psia (101.3 kPa). ASHRAE Standard 
34-2019 requires testing at that temperature to determine if flame 
propagation exists and if not, tests at 140 [deg]F (60 [deg]C) are 
conducted to determine the refrigerant flammability classification. For 
further information on the ASHRAE safety group classifications, see the 
2020 NPRM at 85 FR 35882.
4. What are R-32, R-452B, R-454A, R-454B, R-454C and R-457A and how do 
they compare to other refrigerants in the same end-use?
    R-32 is a refrigerant with lower flammability, and the five 
refrigerant blends are refrigerant blends with lower flammability, all 
with an ASHRAE safety classification of A2L. The respective CAS Reg. 
Nos. of R-32 and the components of the five refrigerant blends are 
listed below.
    R-32 is also known as HFC-32 or difluoromethane (CAS Reg. No. 75-
10-5). EPA previously listed R-32 as an acceptable refrigerant for some 
types of residential and light commercial air conditioning and heat 
pumps end-use categories, specifically self-contained room air 
conditioners such as window units, packaged terminal air conditioners 
(PTACs), packaged terminal heat pumps (PTHPs), portable room AC, and 
wall-mounted AC (80 FR 19454, April 10, 2015). As noted in the 2020 
NPRM, this action adds a listing for this substitute to include rooftop 
units, ground-source heat pump (GSHPs) and water-source heat pump 
(WSHPs), which are typically self-contained but not sized for a single 
room, and various types of split systems.
    R-452B, also known by the trade name ``OpteonTM XL 55,'' 
and also known as ``Solstice[supreg] L41y,'' is a blend with lower 
flammability consisting of 67 percent by weight HFC-32; seven percent 
HFC-125, also known as 1,1,1,2,2-pentafluoroethane (CAS Reg. No. 354-
33-6); and 26 percent HFO-1234yf, also known as 2,3,3,3-
tetrafluoroprop-1-ene (CAS Reg. No. 754-12-1). R-454A, also known by 
the trade name ``OpteonTM XL 40,'' is a blend with lower 
flammability consisting of 35 percent HFC-32 and 65 percent HFO-1234yf. 
R-454B, also known by the trade names ``OpteonTM XL 41'' and 
``Puron AdvanceTM,'' is a blend with lower flammability 
consisting of 68.9 percent HFC-32 and 31.1 percent HFO-1234yf. R-454C, 
also known by the trade name ``OpteonTM XL 20,'' is a blend 
with lower flammability consisting of 21.5 percent HFC-32 and 78.5 
percent HFO-1234yf. R-457A, also known by the trade name 
``Forane[supreg] 457A,'' is a blend with lower flammability consisting 
of 70 percent HFO-1234yf, 18 percent HFC-32, and 12 percent HFC-152a, 
which is also known as ethane, 1,1-difluoro (CAS Reg. No. 75-37-6).
    Redacted submissions and supporting documentation for R-32 and the 
five refrigerant blends are provided in the docket for this rule (EPA-
HQ-OAR-2019-0698) at https://www.regulations.gov. EPA performed an 
assessment to examine the health and environmental risks of each of 
these substitutes, and these assessments are also available in the 
docket for this rule.23 24 25 26 27 28
---------------------------------------------------------------------------

    \23\ ICF, 2020d. Risk Screen on Substitutes in Residential and 
Light Commercial Air-Conditioning and Heat Pumps (New Equipment); 
Substitute: HFC-32.
    \24\ ICF, 2020e. Risk Screen on Substitutes in Residential and 
Light Commercial Air-Conditioning and Heat Pumps (New Equipment); 
Substitute: R-452B.
    \25\ ICF, 2020f. Risk Screen on Substitutes in Residential and 
Light Commercial Air-Conditioning and Heat Pumps (New Equipment); 
Substitute: R-454A.
    \26\ ICF, 2020g. Risk Screen on Substitutes in Residential and 
Light Commercial Air-Conditioning and Heat Pumps (New Equipment); 
Substitute: R-454B.
    \27\ ICF, 2020h. Risk Screen on Substitutes in Residential and 
Light Commercial Air-Conditioning and Heat Pumps (New Equipment); 
Substitute: R-454C.
    \28\ ICF, 2020i. Risk Screen on Substitutes in Residential and 
Light Commercial Air-Conditioning and Heat Pumps (New Equipment); 
Substitute: R-457A.
---------------------------------------------------------------------------

    Environmental information: R-32, R-452B, R-454A, R-454B, R-454C and 
R-457A have ODPs of zero.

[[Page 24458]]

    R-32 has a GWP of 675. The five refrigerant blends are made up of 
the components HFC-32, HFC-125, HFO-1234yf and HFC-152a, which have 
GWPs of 675, 3,500, less than one to four, and 124, 
respectively.\29\ \30\ \31\ \32\ If 
these values are weighted by mass percentage, then R-452B, R-454A, R-
454B, R-454C and R-457A have GWPs of about 700, 240, 470, 150 and 140 
respectively.
---------------------------------------------------------------------------

    \29\ Unless otherwise specified, GWP values are from IPCC (2007) 
Climate Change 2007: The Physical Science Basis. Contribution of 
Working Group I to the Fourth Assessment Report of the 
Intergovernmental Panel on Climate Change. S. Solomon, D. Qin, M. 
Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor and H.L. Miller 
(eds.). Cambridge University Press. Cambridge, United Kingdom 996 
pp.
    \30\ Nielsen et al., 2007. Nielsen, O.J., Javadi, M.S., Sulbaek 
Andersen, M.P., Hurley, M.D., Wallington, T.J., Singh, R. 2007. 
Atmospheric chemistry of CF3CF=CH2: Kinetics 
and mechanisms of gas-phase reactions with Cl atoms, OH radicals, 
and O3. Chemical Physics Letters 439, 18-22. Available 
online at http://www.cogci.dk/network/OJN_174_CF3CF=CH2.pdf.
    \31\ Hodnebrog [Oslash]. et al., 2013. Hodnebrog [Oslash]., 
Etminan, M., Fuglestvedt, J.S., Marston, G., Myhre, G., Nielsen, 
C.J., Shine, K.P., Wallington, T.J.: Global Warming Potentials and 
Radiative Efficiencies of Halocarbons and Related Compounds: A 
Comprehensive Review, Reviews of Geophysics, 51, 300-378, 
doi:10.1002/rog.20013, 2013.
    \32\ WMO (World Meteorological Organization), Scientific 
Assessment of Ozone Depletion: 2018, Global Ozone Research and 
Monitoring Project-- Report No. 58, 588 pp., Geneva, Switzerland, 
2018. Available at: https://ozone.unep.org/sites/default/files/2019-05/SAP-2018-Assessment-report.pdf. In this action, the 100-year GWP 
values are used.
---------------------------------------------------------------------------

    HFC-32 (CAS Reg. No. 75-10-5), HFC-125 (CAS Reg. No. 354-33-6), 
HFC-152a (CAS Reg. No. 75-37-6), and HFO-1234yf (CAS Reg. No. 754-12-
1)--the components of the five refrigerant blends--are excluded from 
the definition of VOC under CAA regulations (see 40 CFR 51.100(s)) 
addressing the development of SIPs to attain and maintain the NAAQS.
    Knowingly venting or otherwise knowingly releasing or disposing of 
these refrigerants in the course of maintaining, servicing, repairing 
or disposing of an appliance or industrial process refrigeration is 
prohibited as provided in section 608(c)(2) of the CAA and EPA's 
regulations at 40 CFR 82.154(a)(1).
    Flammability information: R-32 and the five refrigerant blends are 
designated under ASHRAE flammability classification of 2L, which is a 
classification for refrigerants also referred to as ``lower 
flammability'' (i.e., lower than those designated as 2 or 3) in ASHRAE 
Standard 34-2019. See section 3 above for information on ASHRAE 
classifications.
    Toxicity and exposure data: Potential health effects of exposure to 
these substitutes include drowsiness or dizziness. The substitutes may 
also irritate the skin or eyes or cause frostbite. At sufficiently high 
concentrations, the substitutes may cause irregular heartbeat. The 
substitutes could cause asphyxiation if air is displaced by vapors in a 
confined space. These potential health effects are common to many 
refrigerants.
    ASHRAE Standard 34-2019 classifies HFC-32 and the five refrigerant 
blends under the toxicity classification A (``lower toxicity''). The 
AIHA has established WEELs of 1,000 ppm as an 8-hr TWA for HFC-32 and 
the component refrigerants HFC-125 and HFC-152a; the AIHA has 
established a WEEL of 500 ppm as an 8-hr TWA for HFO-1234yf. The 
manufacturer of R-452B, R-454A, R-454B, and R-454C recommends AELs, 
respectively, of 874, 690, 854, and 615 ppm on an 8-hr TWA for these 
blends. EPA anticipates that users will be able to meet the AIHA WEEL 
and manufacturers' AELs and address potential health risks by following 
requirements and recommendations in the manufacturers' SDS, in ASHRAE 
Standard 15, and other safety precautions common to the refrigeration 
and air conditioning industry.
    Comparison to other substitutes in this end-use: R-32 and the five 
refrigerant blends all have an ODP of zero, the same as other 
acceptable substitutes in this end-use.
    R-32 and the five refrigerant blends' GWPs, ranging from about 140 
to about 700, are higher than some of the acceptable substitutes for 
residential and light commercial air conditioning and heat pumps, 
including ammonia absorption, R-290, and R-441A with GWPs ranging from 
zero to three. R-32 and the five refrigerant blends' GWPs are lower 
than some of the acceptable substitutes for residential and light 
commercial air conditioning and heat pumps, such as HFC-134a, R-410A, 
and R-507A with GWPs of 1,430, 2,087.5 and 3,985 respectively.
    Information regarding the toxicity of other available alternatives 
are provided in the listing decisions previously made (see https://www.epa.gov/snap/substitutes-residential-and-light-commercial-air-conditioning-and-heat-pumps). Toxicity risks for R-32 and the five 
refrigerant blends are comparable to or lower than toxicity risks of 
other available substitutes in the same end-use. Toxicity risks can be 
minimized by use consistent with ASHRAE 15 and other industry 
standards, recommendations in the manufacturers' SDS, and other safety 
precautions common in the refrigeration and air conditioning industry.
    Although flammability risk may be greater than flammability risks 
of other available substitutes in the same end-use, this risk can be 
minimized by use consistent with ASHRAE 15 and other industry standards 
such as UL 60335-2-40, recommendations in the manufacturers' SDS, and 
other safety precautions common in the refrigeration and air 
conditioning industry. The use conditions reduce the potential risk 
associated with the flammability of these alternatives so that they 
will not pose significantly greater risk than other acceptable 
substitutes in this end-use.
5. Why is EPA finalizing these specific use conditions?
    As finalized, the use conditions in this SNAP listing include: Use 
only in new equipment, which can be specifically designed for the 
refrigerant; use consistent with the UL 60335-2-40 industry standard, 
including testing, charge sizes, ventilation, usage space requirements, 
and certain hazard warnings and markings; and warnings and markings on 
equipment to inform consumers and technicians of potential flammability 
hazards. Each of these is described in greater detail below. The 
listings with specific use conditions are intended to allow for the use 
of these refrigerants with lower flammability in a manner that will 
ensure they do not pose a greater overall risk to human health and the 
environment than other substitutes in this end-use.
a. New Equipment Only; Not Intended for Use as a Retrofit Alternative
    Under this listing, these refrigerants may be used under the SNAP 
program only in new equipment \33\ designed to address concerns unique 
to flammable refrigerants--i.e., this listing does not allow these 
substitutes to be used as a conversion or ``retrofit'' refrigerant for 
existing equipment. These flammable refrigerants were not submitted 
under the SNAP program to be used in retrofitted equipment, and no 
information was provided on how to address hazards if these flammable 
refrigerants were to be used in equipment that was designed for non-
flammable refrigerants.
---------------------------------------------------------------------------

    \33\ This is intended to mean a completely new refrigeration 
circuit containing a new compressor, evaporator, and condenser.
---------------------------------------------------------------------------

b. UL Standard
    Under this listing, the flammable refrigerants may be used under 
the SNAP program only in equipment that meets all requirements in UL 
Standard

[[Page 24459]]

60335-2-40, Edition 3 for air conditioning equipment. This UL Standard 
indicates that refrigerant charges greater than a specific amount 
(called ``m3'' in the UL Standard and based on the 
refrigerant's LFL) are beyond its scope and that national standards 
might apply, such as for instance ANSI/ASHRAE 15-2019.
    Those participating in the UL 60335-2-40 consensus standards 
process (hereafter ``UL'') have tested equipment for flammability risk 
in residential applications and evaluated the relevant scientific 
studies. Further, UL has developed safety standards including 
requirements for construction and system design, for markings, and for 
performance tests concerning refrigerant leakage, ignition of switching 
components, surface temperature of parts, and component strength after 
being scratched. Certain aspects of system construction and design, 
including charge size, ventilation, and installation space, and greater 
detail on markings, are discussed further below in this section. The UL 
Standard was developed in an open and consensus-based approach, with 
the assistance of experts in the air conditioning industry as well as 
experts involved in assessing the safety of products. While similar 
standards exist from other bodies, such as the IEC, we are relying on a 
specific UL standard because it is the most applicable and recognized 
by the U.S. market. This approach is the same as that in previous rules 
on flammable refrigerants (e.g. 76 FR 78832, December 20, 2011; 80 FR 
19454, April 10, 2015).
    A description of the requirements of UL 60335-2-40 as they affect 
the refrigerants and end-use addressed in this section of our final 
rule follows. This description is offered for information only and does 
not provide a complete review of the requirements in this standard.
    Under this SNAP listing, the refrigerant charge size for 
residential and light commercial air conditioning and heat pumps is 
limited in accordance with the UL Standard. EPA is requiring as a use 
condition adherence to the standard; hence, charge size limits for each 
of the refrigerants by equipment type in accordance with the UL 
Standard apply to this SNAP listing. Annex GG of the standard provides 
the charge limits, air circulation requirements and requirements for 
secondary circuits. The standard specifies requirements for 
installation space of an appliance (i.e., room floor area) and/or air 
circulation or other requirements which are determined according to the 
refrigerant charge used in the appliance, the installation location and 
the type of air circulation of the location or of the appliance. In 
some applications the introduction of outdoor air into a space, also 
known as ventilation, is required. Within Annex GG, Table GG.1 
describes how to apply the requirements to allow for safe use of 
flammable refrigerants. The UL Standard contains provisions for safety 
mitigation. These mitigation requirements were developed to ensure the 
safe use of flammable refrigerants over a range of appliances. In 
general, as larger charge sizes are used, more stringent mitigation 
requirements are required. In certain applications refrigerant 
detection systems (as described in Annex LL, Refrigerant detection 
systems for A2L refrigerants) must be factory installed as part of the 
equipment. Likewise, in some cases refrigerant sensors (as described in 
Annex MM, Refrigerant sensor location confirmation tests) are required. 
The standard does not require audible alarms in most cases and instead 
relies on sensors/detectors to initiate a mitigation strategy such as 
activating ``fan operation and air circulation or ventilation'' if 
refrigerant concentrations are found to exceed certain thresholds. 
Where mechanical ventilation (i.e., fans) is required in accordance 
with Annex GG or Annex 101.DVG, it must be initiated by a separate 
refrigerant detection system either as part of the appliance or 
installed separately. In a room with no mechanical ventilation, Annex 
GG provides requirements for openings to rooms based on several 
factors, including the charge size and the room area. The minimum 
opening is intended to be sufficient so that natural ventilation would 
reduce the risk of using a flammable refrigerant. The standard also 
includes specific requirements for split system appliances using A2L 
refrigerants covering construction, instruction manuals, and allowable 
charge sizes, mechanical ventilation, safety alarms, and, for variable 
refrigerant flow (VRF) systems, shut off valves.
    In addition to Annex GG and Table GG.1 mentioned above, UL 60335-2-
40 has a requirement for the maximum charge for an appliance using an 
A2L refrigerant. If the appliance is a portable appliance, a non-fixed 
factory-sealed single package, or a cord-connected appliance which may 
be periodically or seasonally relocated (excluding servicing) by the 
end user, there are no additional requirements for room area and air 
circulation if the charge is sufficiently small--under three times the 
LFL; however risk mitigation for labeling, ignition source controls and 
other features are required. Additional requirements exist for charge 
sizes exceeding three times the LFL.
i. Incorporation by Reference
    Through this action, EPA is incorporating by reference the 2019 UL 
Standard 60335-2-40, 3rd Edition, which establishes requirements for 
the evaluation of electrical air conditioners, heat pumps, and 
dehumidifiers, and safe use of flammable refrigerants. The standard is 
discussed in greater detail elsewhere in this preamble. This approach 
is the same as that used to incorporate the 8th edition of UL Standard 
484 in our previous rule in which we listed R-32 as acceptable, subject 
to use conditions, for use in self-contained room air conditioners for 
residential and light commercial AC (80 FR 19454, April 10, 2015).
    The 2019 UL Standard 60335-2-40, 3rd Edition, is available at 
https://www.shopulstandards.com/ProductDetail.aspx?UniqueKey=36463, and 
for purchase by mail at: Comm 2000, 151 Eastern Avenue, Bensenville, IL 
60106; Email: orders@shopulstandards.com; Telephone: 1-888-853-3503 in 
the U.S. or Canada (other countries dial 1-415-352-2178); internet 
address: https://www.shopulstandards.com. The cost of the 2019 UL 
Standard 60335-2-40, 3rd Edition is $440 for an electronic copy and 
$550 for hardcopy. UL also offers a subscription service to the 
Standards Certification Customer Library that allows unlimited access 
to their standards and related documents. The cost of obtaining this 
standard is not a significant financial burden for equipment 
manufacturers and purchase is not necessary for those selling, 
installing, and servicing the equipment. Therefore, EPA concludes that 
the UL standard being incorporated by reference is reasonably 
available.
c. Labeling
    As a use condition, EPA is requiring labeling of residential and 
light commercial air conditioning and heat pump equipment. EPA is 
requiring the warning labels on the equipment contain letters at least 
\1/4\ inch high. The label must be permanently affixed to the 
equipment. Warning label language requirements are described in section 
II.B.1.c of this rule as well as in the regulatory text. The warning 
label language is similar to or exactly the same as that required in UL 
60335-2-40.
d. Markings
    Our understanding of the UL Standard is that red markings, similar 
to

[[Page 24460]]

those EPA has applied as use conditions in past actions for flammable 
refrigerants (76 FR 78832, December 20, 2011; 80 FR 19454, April 10, 
2015), are required by the UL Standard for A2 and A3 refrigerants but 
not A2L refrigerants. The final use condition requires that such 
markings apply to these A2L refrigerants as well to establish a common, 
familiar and standard means of identifying the use of a flammable 
refrigerant.
    These red markings will help technicians immediately identify the 
use of a flammable refrigerant, thereby potentially reducing the risk 
of using sparking equipment or otherwise having an ignition source 
nearby. The AC and refrigeration industry currently uses red-colored 
hoses and piping as means for identifying the use of a flammable 
refrigerant based on previous SNAP listings. Likewise, distinguishing 
coloring has been used elsewhere to indicate an unusual and potentially 
dangerous situation, for example in the use of orange-insulated wires 
in hybrid electric vehicles. Currently in SNAP listings, color-coded 
hoses or pipes must be used for ethane, HFC-32, isobutane, propane, or 
R-441A in certain types of equipment. All such SNAP listings indicate 
that the tubing, hoses, etc. must be colored red PMS #185 or RAL 3020 
to match the red band displayed on the container of flammable 
refrigerants under the AHRI Guideline N, ``2016 Guideline for 
Assignment of Refrigerant Container Colors.'' EPA is requiring red 
markings in this SNAP final action to ensure that there is adequate 
notice for technicians and others that a flammable refrigerant is being 
used within a particular piece of equipment or appliance. These 
requirements are also intended to provide adequate notification of the 
presence of flammable refrigerants for personnel disposing of 
appliances containing flammable refrigerants. Consistent with a 
previous SNAP rule, one mechanism to distinguish hoses and pipes is to 
add a colored plastic sleeve or cap to the service tube. (80 FR 19465, 
April 10, 2015). The colored plastic sleeve or cap would have to be 
forcibly removed in order to access the service tube. Likewise, red 
tape adhered to or around the tube would meet the intent of this use 
condition. These types of red markings would signal to the technician 
that the refrigeration circuit that she/he was about to access 
contained a flammable refrigerant, even if all warning labels were 
somehow removed or were illegible or not understood (e.g., for non-
English speakers), and would provide similar notification to consumers, 
retail store owners, building owners and operators, first responders, 
and those disposing the appliance. This sleeve or other marking would 
be of the same red color (PMS #185 or RAL 3020) and could also be 
boldly marked with a graphic to indicate the refrigerant was flammable. 
This could be a cost-effective alternative to painting or dyeing the 
hose or pipe.
    In this SNAP listing, EPA is requiring the use of color-coded 
service ports, hoses or piping as a way for technicians and others to 
recognize that a flammable refrigerant is used in the equipment. This 
will be in addition to the use of warning labels discussed above. EPA 
believes having two such warning methods is reasonable and consistent 
with other general industry practices. This approach is the same as 
that adopted in our previous rules on flammable refrigerants (e.g., 76 
FR 78832, December 20, 2011; 80 FR 19454, April 10, 2015).
6. What additional information is EPA including in these listings?
    EPA is including recommendations, found in the ``Further 
information'' column of the regulatory text at the end of this 
document, to inform personnel of other practices to protect them from 
the risks of using flammable refrigerants. Similar to our previous 
listing of flammable refrigerants for this end-use (80 FR 19454, April 
10, 2015), EPA is including information on the OSHA requirements at 29 
CFR part 1910, proper ventilation, personal protective equipment, fire 
extinguishers, use of spark-proof tools and equipment designed for 
flammable refrigerants, and training.
    Since this additional information is not part of the regulatory 
decision, these statements are not binding for the use of the 
substitutes under the SNAP program. However, the information so listed 
may be binding under other regulatory programs (e.g., worker protection 
regulations promulgated by OSHA). The ``Further information'' 
identified in the listing does not necessarily include all other legal 
obligations pertaining to the use of the substitutes. While the items 
listed would not be legally binding under the SNAP program, EPA 
encourages users of substitutes to apply all statements in the 
``Further information'' column in their use of these substitutes. In 
many instances, the information simply refers to sound operating 
practices that have already been identified in existing industry and/or 
building codes or standards. Thus, many of the statements, if adopted, 
would not result in the user making significant changes in existing 
operating practices.
    EPA notes that Annex HH of UL 60335-2-40, Competence of service 
personnel, provides guidelines for service personnel to ensure they 
receive training specifically to address potential risks of servicing 
equipment using flammable refrigerants. Annex HH provides 
recommendations that such training cover several aspects relevant to 
flammable refrigerants including recognition of ignition sources, 
information about refrigerant detectors, and other safety concepts. The 
training information recommended in Annex HH would address the proper 
working procedures for equipment commissioning, maintenance, repair, 
decommissioning and disposal. The Agency notes that this section of the 
UL Standard is described as informational, rather than ``normative,'' 
i.e., it is intended to provide information but not to be an absolute 
requirement under the UL standard. Because Annex HH is informative, 
rather than normative, it is not a requirement of the UL Standard and 
following it is not required under the use conditions finalized in this 
action. Nonetheless, EPA is providing as ``Further information'' some 
information on training, including a recommendation that personnel 
follow Annex HH.
7. How is EPA responding to comments on residential and light 
commercial air conditioning and heat pumps?
    EPA received several comments from organizations with various 
interests in residential and light commercial AC. Most commenters 
supported the proposed listing decision in general. Major topics raised 
by commenters included the proposed use conditions, industry standards, 
and training for technicians. Other comments unrelated to these 
listings and beyond the scope of this final action are addressed in 
section III below.
    Commenters included AHRI, Air Conditioning Contractors of America 
(ACCA), the Alliance, and HARDI, four industry organizations; Chemours 
and Honeywell, two chemical producers; Carrier, Daikin, Johnson 
Controls, Lennox International Inc., the Sporlan division of Parker 
Hannifin Corporation (Sporlan), Rheem Manufacturing Company, and Trane 
Technologies (Trane), seven equipment manufacturers; and two 
environmental organizations, NRDC and EIA.
    We have grouped comments together and responded to the issues 
raised by the comments in the sections that follow.

[[Page 24461]]

a. Substitutes and End-Use Proposed
    Comment: Several commenters voiced general support for the proposed 
listing of HFC-32, R-452A, R-454A, R-454B, R-454C, and R-457A as 
acceptable subject to use conditions in residential and light 
commercial air conditioning and heat pumps. Chemours likewise supported 
the proposal. Daikin voiced strong support and encouraged EPA to 
approve HFC-32 quickly, noting that ``[o]ver 100 million R-32 split 
system air conditioners have been sold since 2012'' and provided a list 
showcasing their and other manufactures' implementation of air 
conditioning products using A2L refrigerants in other countries. HARDI 
supported these listings as ``one part of a larger process in the 
industry's effort to phase down older refrigerants.''
    Response: EPA acknowledges these commenters' general support for 
this proposed listing and appreciates the additional information 
provided by Daikin on the use of HFC-32. We add to that information 
that it has been reported that products using HFC-32 are operating in 
over 90 countries.\34\ After considering all the public comments on 
this proposal, we are finalizing this portion of the rule as proposed 
with only a few modifications discussed elsewhere in this final rule.
---------------------------------------------------------------------------

    \34\ The Air Conditioning, Heating, and Refrigeration News, An 
HVAC Technician's Guide to R-32, November 12, 2020. Available at 
https://www.achrnews.com/articles/144053-an-hvac-technicians-guide-to-r-32?oly_enc_id=8731J4776701J6C.
---------------------------------------------------------------------------

b. Clarifications
    Comment: AHRI suggested that rather than ``mildly flammable 
refrigerants'' EPA use the term ``refrigerants with lower 
flammability'' to remain consistent with ASHRAE classifications.
    Response: EPA acknowledges this correction and has used the ``lower 
flammability'' description for the A2L refrigerants in the preamble to 
this final rule. In the ``Further information'' column of the 
regulatory text in this final rule, we have used the term ``Flammable'' 
to replace the term ``Mildly flammable'' that was contained in the 2020 
NPRM.
    Comment: AHRI pointed out that EPA indicated class 2L flammability 
is determined based on testing at 73.4 [deg]F (23.0 [deg]C). They noted 
that ASHRAE Standard 34-2019 requires testing at that temperature to 
determine if flame propagation exists and if not, tests at 140 [deg]F 
(60 [deg]C) are conducted to determine the refrigerant flammability 
classification.
    Response: EPA acknowledges this clarification, which is 
incorporated in the description of the ASHRAE standard testing 
procedures to determine flammability classification in section II.B.3 
above.
    Comment: AHRI provided additional detail on requirements contained 
in UL 60335-2-40 and stated that some of the summary information EPA 
provided (85 FR 35884-34885, June 12, 2020) may be taken out of context 
or be incorrect. For instance, they stated alarms might not be required 
for most systems and if refrigerant concentrations are found to exceed 
certain thresholds a mitigation strategy such as ``fan operation and 
air circulation or ventilation'' would be activated; shut-off valves 
are only an option for VRF systems; connected space requirements exist 
for duct-free equipment but are not required for ducted systems with 
sensors/detectors; mitigation requirements for labeling, ignition 
source controls, and other features are required for portable 
appliances with charge sizes less than three times the LFL; that 
similar requirements exist for fixed appliances where the charge is 
less than six times the LFL; that detectors are required to be factory 
installed, qualified and listed with the product for equipment above a 
charge size calculated per the standard; outdoor air ventilation is 
required ``[o]nly in a few cases;'' and while Annex HH is informative 
as EPA stated in the proposal, installation and service instructions 
are required by the UL standard and that these instructions would 
tailor Annex HH recommendations to the specific product. Carrier 
pointed out that Annex DD of the standard, while also informative, 
provides guidance on what information should be included in operation, 
service and installation manuals.
    Response: EPA acknowledges these clarifications and we agree with 
the commenters' more detailed characterization of certain aspects of UL 
Standard 60335-2-40. Our description in section II.B.5 above is offered 
only for informational purposes and is not meant to be an exhaustive 
summary of the standard. We emphasize that our use conditions are not 
reliant on that informational description but rather adherence to the 
actual requirements in the standard, which is incorporated by reference 
in this rulemaking.
    Comment: AHRI stated that the proposed rule would require the use 
of spark-free equipment but states such tools ``are not required for 
A2L refrigerants as these refrigerants have a high minimum ignition 
energy and sparks from tools and even some electrical devices is not a 
competent ignition source for an A2L refrigerant due to their higher 
minimum ignition energies.''
    Response: EPA noted in the proposal and reiterates in this final 
rule that the information on spark-free tools is included in the 
``Further information'' column of the regulatory text and so is not a 
requirement of the rule. While we believe the use of spark-free tools 
provides additional risk mitigation for technicians working with 
flammable refrigerants, it was not proposed as a requirement and in 
this final rule we maintain the recommendation in the ``Further 
information'' column.
c. Use Conditions
i. Standards
    Comment: Daikin supported EPA's reliance on UL Standard 60335-2-40 
as a basis for listing as acceptable with a use condition requiring 
adherence to that standard. NRDC, speaking in part about the UL 
Standard, stated that ``EPA's approach of reviewing, adjusting as 
needed, and then adopting these standards' safe use requirements is 
sound.''
    Response: EPA acknowledges Daikin's and NRDC's support for these 
aspects of the proposed listing. After considering all the public 
comments on this proposal, we are finalizing this listing, as described 
in section II.B, including the use conditions related to UL 60335-2-40.
    Comment: Pointing to ASHRAE 15-2019 and the third edition of UL 
60335-2-40, Chemours stated that the ``[a]pplication and product 
standards for the end-uses referenced in the proposed rule are 
complete.'' AHRI stated that industry has proposed requirements to 
reduce risk with A2L refrigerants in UL Standard 60335-2-40, ASHRAE 
Standard 15, and ASHRAE Standard 15.2. They provided some examples of 
these including air circulation as well as control of ignition sources 
and hot surface temperatures. Trane stated EPA's use conditions should 
be linked to the current and future versions of ASHRAE 15 and ASHRAE 
15.2, the latter of which they expected to be published in early 2021. 
They noted that these standards govern the installation, operation and 
maintenance of heating, ventilation, and air conditioning (HVAC) 
systems using A2L refrigerants in commercial and residential 
occupancies.
    Response: EPA understands that other risk mitigation requirements 
have been proposed by the standards project committee for ASHRAE 15 and 
ASHRAE 15.2 and may be used by the HVAC industry, just as mitigation 
requirements have already been

[[Page 24462]]

included in the UL Standard that is adopted as a use condition in these 
final SNAP listings. Nonetheless, we find that these A2L refrigerants 
can be used safely provided the use conditions in this rule are 
followed, including compliance with the requirements of the UL 
Standard. In certain clauses, the UL Standard requires compliance with 
ASHRAE 15. We also note that other authorities might impose additional 
requirements, such as adoption of ASHRAE 15 and 15.2 in building codes, 
that would provide an additional layer of safety above what EPA is 
requiring. If in the future EPA were to determine that additional 
requirements are needed after this rulemaking to ensure safe use of the 
refrigerants in the residential and light commercial AC and heat pumps 
end-use, EPA could consider any relevant changes and if any revisions 
to this final rule should be proposed.
    Comment: The Alliance noted that the standard proposed to be 
incorporated by reference, UL 60335-2-40, 3rd edition, will likely be 
updated again. Daikin noted the standard is a ``continuous maintenance 
standard'' supporting reference to the current edition. AHRI also 
pointed out that ``new and updated standards will become more important 
as standards sunset in the coming years.'' The Alliance expected the 
fourth edition ``soon,'' and forecasted that most products manufactured 
to this standard with the six A2L refrigerants would likely be 
certified to that fourth edition. They asked that ``the UL 60355-2-40 
[sic] standard update to include refrigerants that meet all the 
requirements listed in the fourth edition as well.'' More generally 
they asked that ``references to the standards be updated as new 
editions become available for the products listed in SNAP Rule 23 and 
other rules.'' Carrier also suggested EPA align with new safety 
standards ``as new editions and future revisions become available'' and 
Chemours offered similar suggestions. Sporlan and Trane suggested the 
use condition reference the latest edition of the UL Standard, such 
that the reference remains up to date. Sporlan suggested ``this use 
condition be modified to reference the latest released edition of this 
same standard, instead of tying Rule 23 exclusively to the 3rd 
Edition.'' Trane noted that future editions of the UL Standard are 
already underway and predicted the fourth edition would be complete 
within two years (i.e., by July 27, 2022). Honeywell also supported 
referencing a 4th edition and indicated that the process for writing 
such would start in August 2020 and expected completion in 2021. 
Honeywell asked EPA to wait until the 4th edition is published before 
finalizing these listings of the A2L refrigerants and noted that the 
3rd edition ``does not cover mitigation measures for external fires 
caused by refrigerant leaks.'' AHRI also pointed out that there is an 
ongoing effort to harmonize the relevant safety standards and 
recommended that EPA update references to requirements for compliance 
with product safety standards as new editions and revisions become 
available. Referencing both the third and fourth edition of UL 60335-2-
40 as well as ASHRAE 15-2019 and the proposed ASHRAE 15.2, Johnson 
Controls called for the acceptability listing of these A2L refrigerants 
to be ``contingent upon the completion and harmonization of the 
governing UL and ASHRAE standards for the safe design and application 
of stationary air conditioning.'' Honeywell made a similar point, 
referencing ASHRAE Standards 15 and 15.2, and suggested that these A2L 
listings be delayed until this harmonization process was complete.
    Response: EPA acknowledges the information on further developments 
in the UL 60335-2-40 standard and ASHRAE standards processes. After 
considering all the public comments on this proposal, we are finalizing 
this listing, as described in section II.B. EPA is incorporating by 
reference the 3rd edition of the UL standard (the existing version of 
the standard). As addressed below, we conclude, and several commenters 
agree, that this version adequately addresses the use of these A2L 
refrigerants in the equipment proposed.
    As we noted above, in certain cases the UL Standard refers to 
ASHRAE 15-2019 for compliance. We are not, however, providing a use 
condition based on one or more future editions of this standard, nor do 
we feel it necessary or appropriate to rely on future standards and 
harmonization efforts. Not only does EPA not know exactly what these 
future standards may entail, those commenting on the proposed rule have 
not had the opportunity to review those updates, as they have not yet 
been finalized. Similarly, we do not find it necessary or appropriate 
to wait for such actions to be finalized before taking this action. The 
third edition of the UL Standard included extensive revisions 
specifically to address flammability risks of A2L refrigerants and 
reach industry-wide consensus. We further note that Chemours' comments 
on the 2020 NPRM called finalization of this rule ``critical'' and 
``timely'' and stated that with this final rule, the HVAC ``industry is 
now well prepared to take this important step forward'' in the use of 
lower-GWP--and lower overall risk to human health and the environment--
refrigerants in this end-use. If and when a 4th edition of the UL 
Standard is released, EPA can consider any relevant changes and if any 
revisions to this final rule should be proposed.
    Further, as mentioned by AHRI and Daikin, the UL standards are 
under continuous maintenance--as are ASHRAE Standards 15 and 15.2--and 
hence may change again even after the mentioned editions are published. 
Nonetheless, most commenters supported moving forward with the rule 
using the third edition of the UL Standard. Daikin, for instance, 
``endorses EPA's determination that this consensus safety standard 
adequately protects against the reasonably foreseeable risks associated 
with the use of R-32 in the applications being considered.'' Chemours 
added that ``[a]pplication and product standards for the end-uses 
referenced in the proposed rule are complete'' and that ``these updated 
standards sufficiently address the risks associated with the use of A2L 
solutions.'' EPA concludes that reliance on the current UL Standard and 
our other use conditions allows applicable products to be used safely.
    Regarding Honeywell's comment on external fires, we note that a 
leak, even of a flammable refrigerant, does not ``cause'' a fire. It 
would require an ignition source and a concentration of the refrigerant 
higher than the lower flammability limit and below the higher 
flammability limit. Requirements in the UL Standard mitigate the risk 
of the equipment serving as an ignition source. As noted above, AHRI 
pointed out that ``[f]or almost all applications air circulation will 
be sufficient to dilute the refrigerant concentration in the event of a 
catastrophic leak to below 25% of the LFL. Only in [a] rare case will 
ventilation be used to introduce outside air.'' Further, the industry 
is actively studying the behavior of A2L refrigerants (presuming a leak 
does occur) in a structural fire. Should the results of this research 
or other information lead in the future EPA to determine that 
additional requirements are needed after this rulemaking to ensure safe 
use of the refrigerants in the residential and light commercial AC and 
heat pumps end-use, EPA could consider any relevant changes and if any 
revisions to this final rule should be proposed.
    We understand that the Alliance is asking EPA to modify the use 
condition so that it requires adherence to the fourth edition once the 
fourth edition

[[Page 24463]]

publishes, similar to suggestions from other commenters, and to also 
consider revising the listing beyond the six refrigerants in this 
rulemaking to others. If in the future an updated standard is 
published, or the harmonization with other standards is completed, EPA 
could consider any relevant changes and if any revisions to this final 
rule should be proposed. In a similar manner, and through the normal 
SNAP submission review, we can consider taking future action to list, 
or propose to list with use conditions, other refrigerants if we were 
to determine we had enough information to do so.
    Comment: Honeywell predicted that ASHRAE Standard 15.2 would be 
published in late 2021 or early 2022 and then adopted into model 
building codes in 2024. They asked EPA to delay finalization of this 
rule listing of A2L refrigerants until these actions occurred. They 
stated that ``[c]urrent model mechanical and fire codes prohibit mildly 
flammable refrigerants to be used in direct HVAC systems.''
    Response: EPA has not participated in the revisions to the model 
codes discussed by Honeywell, and we find that these SNAP listings can 
be finalized before Honeywell's prediction that a proposed standard 
would be adopted into such codes, consistent with how we have proceeded 
with other listings in past SNAP actions that could be affected by 
anticipated revisions to building codes. As noted both in the proposal 
and above in this final rule, however, information listed in the 
``Further information'' column of the listings might refer to ``sound 
operating practices that have already been identified in existing 
industry and/or building codes or standards.'' (85 FR 35885, June 12, 
2020). The listings in this final rule find certain refrigerants 
acceptable and establishes EPA's use conditions, and do not require any 
particular entity to use these refrigerants. Should other requirements 
or standards also apply, such as building codes as Honeywell states, 
other authorities would be responsible for ensuring such requirements 
are addressed and enforced. We also note that some states are in the 
process of updating their building code requirements to allow for 
refrigerants with lower flammability (e.g., 2Ls), which will address 
Honeywell's concern that such codes ``prohibit mildly flammable 
refrigerants.'' Further, we are aware of the safe use of 2L 
refrigerants in the end-uses covered by this rule in other countries. 
While other states' building codes might currently prohibit use of 
these refrigerants, the adoption by some states and the safe use 
demonstrated gives support to listing these now. Further, we note that 
regardless of the status of building codes, alternative means and 
measures exist under which interested parties may present to the 
Authority Having Jurisdiction (AHJ) evidence to demonstrate a similar 
level of safety as provided under the existing building codes and 
receive an exception to use an A2L refrigerant. For these reasons, the 
Agency determines it is appropriate to finalize this final rule now. If 
and when building codes are updated as indicated by the comment, EPA 
can consider any relevant changes and if any revisions to this final 
rule should be proposed.
    Comment: Rheem asked EPA to ``[p]rovide revised guidance for charge 
limits for R-32 refrigerant, currently defined in SNAP Notice 25 and 
based on unit capacity, to be governed by the safety standards.''
    Response: We believe Rheem is referring to SNAP Rule 19 (80 FR 
19454, April 10, 2015) wherein EPA found HFC-32 acceptable, subject to 
use conditions, for self-contained room air conditioners. One use 
condition referenced parts of the August 3rd, 2012 version of UL 
Standard 484, Edition 8 and another set charge size limits based on the 
type of equipment (window unit, portable room AC, etc.) and cooling 
capacity. In the proposal for this final rule we noted that we were not 
proposing to revisit or modify the existing requirements from SNAP Rule 
19, and consistent with that proposal, we are not finalizing changes to 
these requirements. EPA understands that the standard we relied on in 
Rule 19 might ``sunset'' in the future. Therefore, we will continue to 
evaluate the market for the equipment addressed in that rule, including 
HFC-32 in self-contained room air conditioners, and whether to 
establish new or revised use conditions that reference UL 60335-2-40. 
If in the future we wish to revise the existing requirements for HFC-32 
self-contained room air conditioners, EPA could consider any relevant 
changes and if any revisions to this final rule, or SNAP Rule 19, 
should be proposed.
ii. New Equipment
    Comment: AHRI, Carrier, Daikin, EIA, Honeywell, Johnson Controls 
and Lennox strongly support the proposed use condition that these A2L 
refrigerants may only be used in new equipment and not retrofits. AHRI 
noted that ``refrigerants from a higher ASHRAE flammability 
classification'' should not be used to retrofit existing equipment; 
i.e., these A2L lower flammability refrigerants should not be used to 
retrofit systems using A1 (``no flame propagation'') refrigerants, such 
as R-410A. Carrier added that such a use condition continues EPA's 
precedent from similar listings of flammable refrigerants that were 
only listed for new equipment.
    Response: EPA acknowledges these commenters' support of our 
proposed use condition that finds these refrigerants acceptable for new 
equipment and not for retrofits. After considering all the public 
comments on this proposal, we are finalizing this listing, as described 
in section II.B., including that use condition.
    Comment: AHRI, Carrier, Chemours, Daikin, Johnson Controls, and 
Rheem sought clarification on footnote 33 in the proposed rule, which 
sought to distinguish a ``new'' system from a ``retrofitted'' system. 
AHRI noted that since the inception of the International Building Codes 
in the 1990s, nail strips have been required to be used to support 
existing piping within 1.5 inches of a wall when a new system is 
installed. AHRI also indicated that any ``[e]xisting external piping 
must be pressure-tested, leak-checked and vacuum-checked per the safety 
standards during the installation process,'' a point also noted by 
Johnson Controls. Daikin pointed to provisions in UL Standard 60335-2-
40 that address situations where ``partial units'' (as defined in the 
Standard) are installed without new refrigerant tubing between indoor 
and outdoor components. They also noted that clause DD.3.1DV.2 of the 
UL Standard provides mandatory requirements, including strength test, 
leak tightness checks, and compliance with national and local codes, 
for field-installed refrigerant tubing and as such tubing meeting those 
conditions may be reused. Carrier stated that ``[l]ine sets, however, 
have been safely re-used in the HVACR field for decades'' and noted 
that equipment manufacturer installation instructions and standards, 
such as UL 60335-2-40 and ASHRAE 15, allow for reuse of line sets 
provided they meet requirements including ``line sizing, as well as 
pressure and vacuum testing of the line sets to ensure they are free of 
leaks.'' Chemours offered similar observations. Rheem asked that 
``external field-erected line sets'' be excluded from the definition of 
a new unit, observing that replacement of these should be left to the 
AHJ such as a building code inspector. Carrier and Chemours offered 
alternative language for the footnote and suggested providing such 
guidance in appendix W of the proposed regulatory text where the 
listing is provided. On the other hand,

[[Page 24464]]

Honeywell states that the definition of ``new system'' should require 
the installation of new refrigerant piping, tubing or linesets and 
later stated that ``the tubing must be replaced, or at least inspected 
and reinforced to meet proposed requirements under ASHRAE 15.2.'' They 
said that existing tubing was not likely to meet minimum safety 
regulations. Trane said ``[b]asing the proposed use conditions on 
ASHRAE 15 and ASHRAE 15.2 incorporates appropriate piping guidance and 
avoids the potential of unnecessary and costly restrictions.''
    Response: After consideration of these comments, EPA concludes that 
the use of existing piping that is consistent with the use conditions 
finalized--such as adherence to the UL 60335-2-40 Standard and the 
inclusion of markings and labels as required--and the safety protocols 
mentioned should not pose additional risk. We have clarified this in 
section II.B.5.a and likewise in the text of the corresponding footnote 
in section II.B.1.b of this final rule by not including ``refrigerant 
tubing'' in the description of new equipment in this final action. As 
such, existing piping does not need to be replaced for the equipment to 
be considered ``new'' while a new compressor, evaporator, and condenser 
are all required to be considered ``new.'' We believe this preamble 
text sufficiently indicates our intention and so have not included 
additional discussion in the regulatory text.
    As noted by other comments, discussed elsewhere in this final rule, 
the UL Standard 60335-2-40, which is incorporated by reference through 
this rule, addresses the situations where existing tubing might be used 
when installing a new system using a refrigerant in this rule. 
Consistent with the use conditions established in this rule, EPA finds 
that this standard provides appropriate criteria by which an installer 
would decide when exiting tubing may be used or needs to be replaced. 
Accordingly, EPA concludes it is not necessary or appropriate to define 
a ``new'' system to require installation of new refrigerant piping, 
tubing or linesets. If the existing tubing and linesets do not meet 
existing regulations separate from the UL Standard and our other use 
conditions, e.g. applicable building codes, other regulations or other 
authorities may require installation of new refrigerant piping, tubing 
or linesets. EPA also does not find it appropriate to adopt ``proposed 
requirements,'' including those proposed in October for ASHRAE 15.2, as 
those have not been finalized and neither commenters nor EPA can know 
the future content of a standard for certain until it is finalized.
    Comment: Carrier brought up the possibility that an outdoor 
condensing unit using a non-flammable refrigerant (e.g., HCFC-22 or R-
410A) might illegally be replaced with one of the six refrigerants in 
the listings in this final rule. Carrier urged EPA to work with the 
industry concerning the replacement of all components, e.g. including 
the indoor unit, as these instances will exhibit ``inspection and 
enforcement challenges.''
    Response: EPA notes that the final listings of these six 
refrigerants require they be used in a new system, including the 
replacement of the indoor unit of an existing HCFC-22 or R-410A system 
when the corresponding outdoor unit is replaced. We support education 
and training across the industry to improve awareness of and compliance 
with the requirements of this final rule. EPA intends to continue to 
work with industry towards these goals.
    Comment: Carrier and Chemours sought clarification where EPA stated 
in footnote 33 that the use condition for ``new equipment'' meant a 
``completely new circuit.'' Chemours noted that a literal translation 
of that might be to require that an entire system be replaced, even if 
in the future a repair was being conducted on a system using one of the 
six A2L refrigerants in this final rule.
    Response: EPA acknowledges Carrier's and Chemours' comments 
pointing out this potential misinterpretation of the use condition. 
Under the use conditions finalized in this rule, EPA intends that once 
systems using these A2L refrigerants are installed, technicians, using 
proper safety procedures, may service the equipment similarly to 
servicing current day equipment using A1 refrigerants. This intention 
to allow servicing and not strand equipment prematurely is consistent 
with prior SNAP decisions, as well as with approaches that we have 
taken under other provisions of Title VI of the CAA to achieve a smooth 
phaseout and transition to safer alternatives. Such service would 
include replacing components including the condensing unit, and other 
adjustments. In those cases where one of the heat exchangers needs 
replacing, EPA recommends that outdoor units and indoor units be 
properly matched, including for instance replacing a functioning indoor 
A2L evaporator unit if warranted when the original A2L outdoor unit is 
replaced with a higher-efficiency outdoor unit using that same A2L 
refrigerant.
iii. Labels
    Comment: AHRI, the Alliance, Carrier, Chemours, Daikin, Johnson 
Controls, Lennox, and Rheem suggested that EPA rely on the labeling 
requirements found in UL 60335-2-40, including the font size 
requirement in the standard. Carrier held that the \1/8\-inch font size 
specified in the standard is ``easily readable'' and further noted that 
``visual icons and flammability symbols'' are required by the standard. 
Lennox felt this size, which is half the size required in other EPA 
listings (e.g., 80 FR 19454, April 10, 2015), was justified given the 
refrigerants proposed have lower flammability (A2L) whereas the 
referenced listings were for higher flammability refrigerants (A3). 
Chemours stated that using a larger font ``disproportionally emphasizes 
flammability versus other safety aspects including electrical or 
pressure requirements.'' Rheem said that diverging from the UL Standard 
``adds unnecessary complexity'' and Johnson Controls held that ``[t]he 
introduction of new, unique requirements could lead to confusion in the 
field and thus increase safety risks.'' EIA, on the other hand, 
``strongly supports the labelling requirements . . . outlined on the 
proposed rulemaking.''
    Response: As in other regulations promulgated under CAA section 
612, EPA concludes that the proposed labeling requirement to use \1/4\-
inch fonts provides for an easier-to-read label than the \1/8\-inch 
fonts in the standard; hence, the large font size provides an extra 
layer of risk mitigation for technicians, consumers, retail store 
owners, building owners and operators, first responders, and those 
disposing of the equipment to readily understand the possibility that 
the equipment contains a flammable refrigerant. Accordingly, EPA is 
finalizing the larger text size as proposed.
    The only differences to the actual text of the label between UL 
60335-2-40 and the requirement proposed and finalized in this rule are 
to the label(s) on the indoor unit, where for instance the minimum 
installation height in meters (m) and feet (ft) is to be referred to in 
the format ``X m (Y ft)'' rather than ``X m and Y ft'' as in the UL 
Standard, with X and Y calculated per the standard (85 FR 35881, June 
12, 2020). EPA believes the format is appropriate and would help avoid 
possible confusion if an installer were to interpret the label as 
called for in the UL Standard to mean X meters plus Y feet (i.e., 4.28 
times Y feet or 1.305 times X meters). Likewise, we proposed and are 
finalizing the same change in text

[[Page 24465]]

format for the minimum room area label.
    Comment: AHRI and Daikin indicated EPA could in the future submit a 
proposed change to UL to modify the labeling requirements. AHRI also 
pointed out that there is an ongoing effort to harmonize the relevant 
safety standards and recommended that EPA update references to 
requirements for compliance with product safety standards as new 
editions and revisions become available. They also suggested EPA 
consider incorporating application standards such as ASHRAE 15 when 
this harmonization process is complete.
    Response: As explained above, EPA finds that these A2L refrigerants 
can be used safely provided the use conditions in this final rule are 
followed, including compliance with the current (3rd edition) UL 60335-
2-40. Accordingly, EPA is taking final action on the proposal without 
waiting for the harmonization process to be completed. EPA understands 
that it could submit a change proposal to UL and if in the future EPA 
were to determine that additional use conditions are needed after this 
rulemaking to ensure safe use of the refrigerants in the residential 
and light commercial AC and heat pumps end-use, EPA could consider any 
relevant changes and if any revisions to this final rule should be 
proposed, for instance by proposing to reference a revised standard and 
specific application standards. Given the time required to propose, 
discuss, and finalize any change to the UL Standard, EPA understands 
that such a revised UL standard would not have been finalized for this 
final rule, nor did we expect the harmonization effort to be complete. 
If and when a 4th edition of the UL Standard is released, EPA can 
consider any relevant changes and if any revisions to this final rule 
should be proposed.
    Comment: Carrier stated that ``[t]he consensus safety standard CSA/
UL 60335-2-89 committee included representatives from fire service 
which concluded that the proposed label requirements replicated from 
UL/CSA 60335-2-40 in addition to label requirements for buildings in 
building codes were sufficient from their perspective.'' Lennox made 
the same point, saying the committee that developed the CSA/UL 60335-2-
89 standard ``included representatives from fire services which 
concluded that the UL label requirements were sufficient.''
    Response: EPA appreciates learning that fire service personnel were 
part of the consensus process for the 60335-2-89 standard but notes 
that this is a different UL standard from the one addressed in this 
rule. Thus, any conclusions about the adequacy of the label 
requirements for that standard are not the same as a conclusion that 
the label requirements for the UL standard addressed in this final rule 
is sufficient, including the font size. For example, as the 60335-2-89 
standard covers commercial refrigeration equipment, it is reasonable to 
assume that the fire service personnel were only evaluating the label 
requirements for the types of appliances covered by that standard, and 
not necessarily agreeing to the adequacy of those requirements for the 
equipment covered in this final rule, considering that much of the 
equipment in the residential and light commercial AC and heat pumps 
end-use has higher refrigerant charge sizes than the appliances covered 
in the 60335-2-89 standard. As described elsewhere in this action, we 
are concluding that the larger font size is appropriate under SNAP to 
reduce risks to technicians, consumers, retail store owners, building 
owners and operators, first responders, and those disposing the 
appliance, consistent with EPA's approach in other prior SNAP rules.
    Comment: Daikin stated that the UL Standard was drafted under a 
consensus process and requested that EPA's proposed use conditions 
regarding labels be removed, allowing the standard to address any such 
requirements.
    Response: EPA understands that this UL standard was drafted 
following consensus practices, as were standards referenced in past EPA 
listings of flammable refrigerants (e.g., 76 FR 78832, December 20, 
2011; 80 FR 19454, April 10, 2015). In those cases, as in this action, 
we find that the extra level of safety provided by EPA's labeling 
requirement is appropriate under SNAP and that the larger font size 
will reduce risks to technicians, consumers, retail store owners, 
building owners and operators, first responders, and those disposing 
the appliance. Accordingly, EPA is finalizing the use conditions 
regarding labels as proposed.
iv. Red Markings
    Comment: Chemours indicates that using the same use condition for 
red markings for these A2L refrigerants as was used for A3 refrigerants 
previously listed acceptable amounts to a ``one size fits all'' 
approach. They disagreed that this should be done and specifically drew 
attention to the UL 60335-2-40 standard, which provides different 
requirements for equipment with A2L refrigerants compared to equipment 
with A3 refrigerants. They indicated that ``treating A2 [sic] and A3 
refrigerants the same is likely to cause confusion to end-users, 
especially technicians responsible for installation and maintenance of 
systems.'' Daikin, Lennox, and Rheem commented that the UL Standard was 
adequate and as such the proposed requirement for red markings was not 
warranted. EIA, on the other hand, ``strongly supports . . . the 
required red markings on piping and hoses outlined on the proposed 
rulemaking.''
    Response: EPA is finalizing the proposed requirement for red 
markings. Consistent with other rules promulgated under CAA section 
612, EPA's requirements of red markings add an extra layer of safety on 
top of the labels required under the UL standards, and EPA concludes 
this extra protection is appropriate for this listing under SNAP. As 
noted above, these types of red markings would signal to the technician 
that the refrigeration circuit that she/he was about to access 
contained a flammable refrigerant, even if all warning labels were 
somehow removed or were illegible or not understood (e.g., for non-
English speakers), and would provide similar notification to consumers, 
retail store owners, building owners and operators, first responders, 
and those disposing the appliance. We understand that UL 60335-2-40 
treats A2L and A3 refrigerants differently; however, our proposal and 
this final rule do not cover the A3 refrigerants. EPA relied on 
different standards when we previously listed A3 refrigerants as 
acceptable subject to use conditions and hence we are not treating 
these two classes of refrigerants the same. For this SNAP listing, as 
in our past listings for A3 (and also A2L) refrigerants, EPA concluded 
that it is most important to warn technicians that there is a flammable 
refrigerant present, not whether it is specifically an A2L, A2, or A3 
refrigerant. Once warned, we would expect the technician then seek to 
know which refrigerant is used and to proceed accordingly. While we see 
that the flammability risk can be considered ``lower'' when using A2L 
refrigerants compared to A3 refrigerants, a risk does exist and we find 
that the red markings will provide an additional warning to 
technicians, consumers, retail store owners, building owners and 
operators, first responders, and those disposing the appliance. We also 
note that the use of red markings is already required for HFC-32 as 
well as A3 refrigerants in self-contained room air conditioners based 
on previous regulations (80 FR 19454, April 10, 2015), and we are not 
aware that the marking requirements have led to any confusion.

[[Page 24466]]

    Comment: AHRI read the proposal to be proposing all tubing be red, 
but thought the intent was to only require such markings for service 
ports.
    Response: EPA did not intend to propose that all tubing in 
equipment using A2L refrigerants be red and we are not finalizing such 
a requirement in this final rule. We are finalizing this use condition 
as proposed and clarifying in section II.B.1.d that where the red 
markings would be applied depends primarily on the equipment design. 
The intent in the proposed rule and finalized in this rule is for the 
red marking to be present at all service ports for equipment that 
includes such service ports, and for the marking to extend one inch 
from those ports. Likewise, if connections need to be made in the field 
as opposed to at a factory, the one-inch red marking is required at 
those connection points. If, however, equipment is provided without 
such service ports, the one-inch red marking would be required at the 
point in the equipment where any service involving the refrigerant, 
including the evacuation of the refrigerant prior to equipment 
disposal, would occur. On smaller appliances, we have noted in the past 
that a process tube is often provided for such service, and that the 
red marking would be required there. As we have also noted previously, 
the manufacturer must decide the method of providing the red marking, 
for instance via paint, plastic sleeve, shrink wrap, tape, etc.
    Comment: AHRI described the labeling requirements of the UL 
standard for service ports and indicated that ``use of red markings and 
the use of red hoses may cause some confusion.'' The reason the 
commenter provided was that typical gage sets currently use red housing 
for the higher-pressure side, a comment echoed by Carrier.
    Response: EPA does not agree that the similarity of color between 
the gage set and the servicing port would lead to confusion. Given that 
connections in the gage set also exist for the low-pressure side, we 
feel that technicians would understand that a red marking of a service 
port does not mean that only the red hose of a gage set must be 
connected there. Other EPA requirements, such as the venting 
prohibition under section 608(c) of the CAA and technician training 
requirements, have existed since the early 1990s, and thus EPA believes 
technicians will be able to use gage sets without confusion. Further, 
training on flammable refrigerants which several commenters have 
pointed to would reinforce the understanding of red service ports and 
the use of gage sets. Finally, EPA notes that a similar red coloring 
requirement use condition exists for flammable refrigerants, including 
HFC-32, in other end-uses, and we are not aware that such coloring has 
led to any confusion.
    Comment: Chemours stated that the requirement of red markings would 
be difficult to implement in certain types of residential and light 
commercial air conditioning equipment. As an example, they indicated 
that quick-release Schrader valves ``may be impossible to get in red 
color.''
    Response: EPA does not see evidence that the construction of red-
colored Schrader valves is impossible. In fact, Chemours' comments may 
point to the reason why they say such valves are not available. 
Chemours pointed out that the equipment types where flammable 
refrigerants are currently acceptable subject to use conditions were 
self-contained equipment generally using process tubes rather than 
Schrader valves. Thus, there may have been no reason to develop them in 
the past. However, that does not mean that such valves will not become 
available if there is demand for such valves in the future. Although we 
cannot confirm that such valves do not exist at all, it is important to 
note that other means of applying the red marking may be used. The 
regulatory text proposed and finalized in this rule states the red 
``color must be applied at all service ports;'' hence, items such as a 
red plastic sleeve or shrink wrap at both sides of the port, rather 
than the entire port itself, would be acceptable means of meeting this 
use condition.
d. SNAP Criteria
i. Flammability Risks and Safety
    Comment: AHRI and Lennox pointed to an approximately $7 million 
research effort with the U.S. Department of Energy (DOE), the 
California Air Resources Board (CARB) and other stakeholders on the 
behavior and safe use of next generation refrigerants, including the 
lower toxicity, lower flammability (A2L) refrigerants in the proposed 
rule. Lennox emphasized that such research was used to develop the 
safety standards and develop training. Sporlan said this research on 2L 
refrigerants is ``of mature enough nature that they will be able to be 
safely applied in new systems designed for 2L flammable refrigerants.'' 
AHRI detailed the extensive use of A2L refrigerants in the United 
States and other countries and noted that ``it has yet to find 
incidents related to A2L refrigerants.''
    Response: The Agency acknowledges AHRI's and Lennox's support for 
this proposed listing. EPA acknowledges AHRI and Lennox for providing 
this information and note Sporlan's comment, which supports EPA's 
finding that the flammability risk of A2L refrigerants can be safely 
addressed. After considering all the public comments on this proposal, 
we are finalizing this listing, as described in section II.B.
    Comment: HARDI indicated that the industry is supporting updates to 
the building, mechanical, and fire codes as well as transportation 
regulations to allow new equipment to use new refrigerants, including 
the A2L ones listed in the proposed rule. HARDI is working with the 
industry ``to ensure a smooth and safe transition takes place.''
    Response: EPA acknowledges HARDI's information on their efforts to 
support the safe use of these refrigerants in residential and light 
commercial equipment as well as other types of equipment not covered by 
this final rule.
    Comment: Honeywell commented that EPA should update the Risk 
Screens for R-32 and R-454B included in supporting documents for the 
proposed rule. They suggested that because ASHRAE Standard 15 mandates 
use of a refrigerant concentration limit (RCL), and ASHRAE Standard 34 
sets the RCL to be 25% of the LFL, EPA should use that amount rather 
than the 100% of LFL.
    Response: EPA has consistently evaluated alternatives through a 
risk screen process that begins with a highly conservative worst-case 
scenario, such as where the entire refrigerant charge of a specific 
equipment type leaks out rapidly in a specific room size. If a 
substitute's concentrations remain below 100% of the LFL and relevant 
toxicity limits in the worst-case scenario with highly conservative 
assumptions, we do no further assessment. If the substitute's 
concentrations exceed the LFL or a relevant toxicity limit in the 
worst-case scenario, then we consider more typical scenarios based on 
less conservative assumptions. EPA's risk screens indicate that none of 
the types of equipment in this rule with these refrigerants came close 
to 100% of the LFL, although they did exceed the 25% mark under the 
most conservative scenarios analyzed.
    To the extent ASHRAE 15 is incorporated into building codes--as 
Honeywell indicates--that requirement to adhere to the ASHRAE RCL would 
provide an additional layer of safety above the use conditions set in 
this final rule. More generally, the use of risk screens was developed 
in the original SNAP Rule issued in 1994 and was not meant to 
incorporate every possible risk factor. In fact, in that rule we stated

[[Page 24467]]

``[w]henever the initial risk screen indicated a potential risk, the 
substitute was evaluated further to ascertain whether the potential 
risk was accurately estimated and if management controls could reduce 
any risk to acceptable levels.'' In this case, in the worst-case 
scenario where the 25% RCL was exceeded, we concluded that the 
additional risk mitigation offered by the UL Standard and our other use 
conditions adequately addressed any such risk.
ii. Toxicity and PFAS
    Comment: EIA indicated there are ``concerns regarding potential 
risks to human health and the environment due to toxicity of 
trifluoroacetic acid (`TFA') and other by-products of breakdown of HFO-
1234yf, which is a component of the five refrigerant blends.'' They 
pointed to scientific literature that finds HFO-1234yf has a 100% 
conversion rate into TFA. They noted that increased use of alternative 
refrigerants including HFOs has increased ecosystem levels of 
anthropogenic TFA. EIA advised EPA to lead with caution but did not, 
however, recommend that additional restrictions be placed on these 
refrigerant blends based on TFA concerns. NRDC noted that ``EPA's risk 
analyses do not evaluate the potential human health and environmental 
impacts of approving additional uses for substances known to degrade 
into [TFA].'' NRDC pointed to the previous analyses EPA performed on 
TFA and requested that EPA revise those studies to include the 
potential use of the five blends in the air-conditioning sector.
    Response: EPA does not agree that increased controls on HFOs or 
other refrigerants is warranted to address generation of TFA. EPA 
studied the potential generation of TFA when we first listed neat 
(i.e., 100%, not in blends) HFO-1234yf as acceptable subject to use 
conditions in motor vehicle air conditioners. The myriad studies we 
referenced all concluded that the additional TFA from HFO-1234yf did 
not pose a significant additional risk, even if it were assumed to be 
used as the only refrigerant in all refrigeration and air conditioning 
equipment (76 FR 17492-17493, March 29, 2011). More recently, the World 
Meteorological Organization (WMO) concluded that ``[t]here is increased 
confidence that [TFA] produced from degradation of HFCs, HCFCs, and 
HFOs will not harm the environment over the next few decades'' while 
also calling for periodic reevaluation of this conclusion.\35\ EPA 
likewise finds that the data on TFA is not sufficient to propose or 
establish additional restrictions under SNAP at this time. We further 
note that the venting prohibition under section 608(c) of the CAA, 
codified at 40 CFR 82.154(a), and accompanying refrigerant management 
requirements reduce emissions of these refrigerants. EPA intends to 
continue reviewing the research on potential impacts from TFA in the 
future.
---------------------------------------------------------------------------

    \35\ World Meteorological Organization (WMO), Executive Summary: 
Scientific Assessment of Ozone Depletion: 2018, World Meteorological 
Organization, Global Ozone Research and Monitoring Project--Report 
No. 58, 67 pp., Geneva, Switzerland, 2018. Available at https://ozone.unep.org/sites/default/files/2019-04/SAP-2018-Assessment-report-ES-rev%20%281%29.pdf.
---------------------------------------------------------------------------

    Comment: NRDC asked EPA to revise the Agency's analysis of the 
substances included in this rulemaking that are polyfluoroalkyl or 
perfluoroalkyl substances (PFAS), citing two recent papers on the 
subject.\36\ \37\
---------------------------------------------------------------------------

    \36\ Cousins, Ian T, et al. The concept of essential use for 
determining when uses of PFASs can be phased out. Environmental 
Science: Processes & Impacts. The Royal Society of Chemistry. May 
28, 2019. https://pubs.rsc.org/en/content/articlelanding/2019/em/c9em00163h#!divAbstract.
    \37\ Kwiatkowski, Carol F. et al. Scientific Basis for Managing 
PFAS as a Chemical Class. Environmental Science & Technology 
Letters. June 30, 2020. https://pubs.acs.org/doi/10.1021/acs.estlett.0c00255.
---------------------------------------------------------------------------

    Response: EPA acknowledges these references. Upon review of these 
papers, EPA does not conclude that any revisions to the evaluation of 
overall risk to human health and the environment of the refrigerants 
addressed in this final rule is necessary at this time. While the 
papers NRDC referenced indicate there are potential health effects due 
to accumulation of PFAS in the environment, they do not provide 
information concerning the incremental effect that adoption of the five 
refrigerants listed in this rule for the residential and light 
commercial air conditioning end-use would have or how those effects 
would compare to effects from other available substitutes in this end-
use.
    Both papers reference decision IV/25 by parties to the Montreal 
Protocol on Substances that Deplete the Ozone Layer. That decision 
concerns applying specific criteria and procedures in assessing an 
essential use for the purposes of the control measures in Article 2 of 
the Protocol and therefore is not directly relevant to the SNAP 
program. Cousins et al. reviewed several examples of PFAS uses to 
assess whether they would consider those uses to be ``essential,'' and 
those uses did not include the refrigerants considered in this final 
rule. Kwiatkowski et al. likewise did not provide an overview of 
refrigerants to indicate any additional restrictions that they would 
consider warranted.
    EPA intends to continue monitoring the scientific research on PFAS 
in the future and consider whether this information is relevant for the 
SNAP program.
e. Training
    Comment: ACCA argues that training and certification of technicians 
on the handling of A2L refrigerants is necessary for safety and 
consumer peace of mind. ACCA indicated it and others were developing 
training and guidelines on A2L refrigerants and provided a list of 
several aspects that they are addressing. Carrier noted that industry 
has developed an exam for flammable refrigerants under the North 
American Technician Excellence (NATE) certification organization. 
Chemours also pointed to NATE and ACCA training as well as that by the 
Refrigeration Service Engineers Society (RSES), AHRI, and that provided 
by refrigerant producers and equipment manufacturers. Daikin also noted 
that AHRI is developing guidelines for A2L refrigerants and that 
equipment manufacturers are providing training to their service 
personnel. Chemours stated that ``[t]echnician training, guidelines, 
informational brochures, and certifications for flammable refrigerants 
have been or are currently being developed by a number of industry 
organizations'' and that ``recovery machines, leak detectors, service 
cylinders and fittings are also available to the industry.'' HARDI 
indicated the industry is supporting ``the development of training to 
allow contractors to install newly designed equipment.'' ACCA asked EPA 
to work with them and other industry stakeholders ``to develop and 
implement training standards for the handling of flammable 
refrigerants.'' Carrier similarly encouraged industry stakeholder 
engagement and Chemours stated that given the number of programs that 
already exist, EPA should collect a wide range of comments and move 
forward with a separate rule on training that incorporates stakeholder 
feedback. Rheem agreed that EPA should not undertake the creation of 
new training requirements in this rule and went further to say they 
were not in favor of a separate rulemaking, believing industry should 
create any new training requirements.
    Response: EPA acknowledges the commenters' information related to 
their work to educate and train technicians on the proper and safe use 
of flammable refrigerants, including the A2L refrigerants in this final 
rule. In the

[[Page 24468]]

proposed rule (85 FR 35886, June 12, 2020), EPA indicated it would take 
advance comments on the possibility of proposing, in a separate rule, 
training and service requirements, and we thank the industry for their 
advance comments. We will take these comments into consideration to 
determine whether we should propose such a rule on training or 
undertake other future action. We note that certain safety requirements 
for refrigerant recovery and/or recycling equipment are already 
included in 40 CFR part 82, subpart F, under EPA's Refrigerant 
Management Program. We also indicated in our proposal, as we did in 
previous rules finding flammable refrigerants acceptable subject to use 
conditions (e.g. 76 FR 78832, December 20, 2011; 80 FR 19454, April 10, 
2015), that industry may be better suited than EPA to develop 
appropriate training, and we see that this development has already 
started across multiple fronts.
    Comment: AHRI ``strongly supports incorporation of new refrigerant 
and requirements regarding A2L refrigerants into existing certification 
requirements.'' The Alliance likewise supported this position asking 
EPA to update the training and certification framework. Rheem 
``encourages EPA to incorporate group A2L and group A3 refrigerants 
into any requirements for training and certification that currently 
exist for group A1 refrigerants.'' (emphasis in original). EIA 
recommended that ``EPA mandate training and servicing requirements for 
all flammable refrigerants'' holding that ``[i]n addition to putting 
consumers at risk, not mandating such training would create confusion 
for contractors if EPA has different rules and standards for different 
refrigerants.''
    Response: Although AHRI and Rheem did not indicate which existing 
training and certification requirements to which they were referring, 
we believe it would include the existing technician certification 
required under regulations implementing section 608 of the Clean Air 
Act. EPA has incorporated information on flammable refrigerants into 
the question bank for tests for such certification, which is required 
to service equipment that contains the refrigerants covered by this 
rulemaking, and has standards in place for refrigerant recovery and/or 
recycling equipment used with such refrigerants. As we consider these 
advance comments, we note that EPA's 608 test bank already includes 
questions concerning A2L refrigerants and the appliances covered by 
this rule, and EPA continues to review the test bank and can consider 
adding additional questions in the future if appropriate. As noted 
above, EPA will consider these advance comments as we determine what, 
if any, additional actions we might take, including considering issuing 
a proposed rulemaking addressing the possibility of mandating certain 
additional training requirements.
    Comment: In their support of a separate rulemaking to update 
training and certification requirements for A2L refrigerants, Carrier 
suggested that a rulemaking provide ``training and service requirements 
for anyone purchasing A2L refrigerants or servicing equipment 
containing A2L refrigerants,'' noting that Australia and Japan have 
credited such requirements in their successful adoption of such 
refrigerants. Johnson Controls recommended a licensing system, 
delivered by trade schools and accredited by established contractor 
trade organizations, for handling A2L refrigerants. They emphasized the 
need for hands-on training, including ``demonstration of skills as it 
relates to the brazing, evacuating, charging, handling, storage, 
transportation, etc. of mildly flammable, A2L refrigerants.''
    Response: EPA acknowledges the suggestion of undertaking a 
rulemaking to provide training and service requirements for technicians 
and the suggestion that it cover those purchasing A2L refrigerants and 
servicing equipment containing them. Likewise, we acknowledge Johnson 
Controls' recommendations of hands-on training and the topics suggested 
to be included in a licensing training curriculum. As noted above, EPA 
is taking these advance comments into consideration for possible future 
industry engagement and possible rulemaking or other future action.
    Comment: EIA commented that industry has ``an aging and diminishing 
workforce that need to be retrained.'' In addition to flammability, 
they opined the training needs to cover other safety aspects including 
health and environmental aspects of venting and accidental release. 
They also stated that ``[t]here is significant confusion and lack of 
clarity when it comes to applicability of the venting prohibition 
itself, which still applies to the maintenance, service, repair, and 
disposal of equipment containing HFCs.'' They noted that ``the 
workforce needs to be provided basic awareness and education of 
refrigerant lifecycle and impacts at different stages'' while also 
noting that such education and training already exists. EIA offered 
suggestions on how the training program they support could be managed, 
such as allowing ``a certain grace period for servicing companies to 
bring technicians into compliance before such training becomes 
mandatory.'' They noted EPA could partner with the Department of Labor 
to ``support the transition to low-GWP alternatives, particularly to 
small businesses and women or minority owned companies,'' possibly 
complementary to apprenticeship programs under the Workforce 
Opportunity and Innovation Act.
    Response: EPA appreciates EIA's concern with respect to 
technicians' handling of refrigerants. We further note that EPA's 
current CAA section 608 technician certification test bank includes 
questions concerning topics such as environmental impacts, laws and 
regulations (including the venting prohibition and its applicability), 
safety, flammable refrigerants, and safe disposal. Under the current 
regulations, EPA can make changes to the test bank.
    EPA observes that while our proposed rulemaking took advance 
comment on the possibility of proposing training and service 
requirements for certain flammable refrigerants through a separate 
rulemaking, we neither proposed to create a complementary technician 
training and certification program in the current rulemaking, nor did 
we propose to modify our existing CAA 608 technician certification 
program in the current rulemaking. We appreciate EIA's suggestions and 
as noted above we will take these comments into consideration in 
determining whether to propose a rule or undertake other future action 
on such training or service requirements.
    Comment: Honeywell stated that ``[a]ny transition to A2L 
refrigerants should also be accompanied by a comprehensive training 
program'' covering the installation and maintenance of equipment 
containing A2L refrigerants. They held that such a training program 
should be established, through rulemaking, by EPA before finalization 
of this rule. Others, including manufacturers intending to use these 
A2L refrigerants in their equipment, disagreed. For instance, Carrier 
said they see no reason to delay this rulemaking in order to initiate a 
separate rulemaking on training and certification for A2L refrigerants. 
Daikin also supported EPA's approach of not proposing specific training 
or service practices at this time, stating that manufacturers using A2L 
refrigerants provide training to their service personnel.
    Response: After considering these comments, we agree with the 
comments that it is not necessary to delay this rulemaking to undertake 
separate action

[[Page 24469]]

on training, certification, or service practices for A2L refrigerants. 
As noted by comments, training is already being provided by some 
manufacturers and several organizations have developed or are in the 
process of developing training. In past rulemakings listing flammable 
refrigerants, we stated our conclusion that training is best left to 
the industry, and we find no reason to change that conclusion in this 
action. We are not aware of any safety issues that have arisen with the 
equipment covered by those rules and our current understanding based on 
comments to this rule is that action is already being taken to 
adequately train service technicians. While we will nonetheless 
consider these advance comments as we determine what, if any, 
additional actions we might take, including considering issuing a 
proposed rulemaking addressing the possibility of mandating certain 
additional training requirements, our current understanding based on 
comments to this rule is that the industry in general and interested 
manufacturers in particular are already preparing for an adequate level 
of training. As noted above, many additional sources are available, and 
more are under development, to provide training on the A2L refrigerants 
in this final rule and on flammable refrigerants in general.

C. Total Flooding: Removal of Powdered Aerosol E From the List of 
Substitutes Acceptable Subject to Use Conditions

    Powdered Aerosol E, also marketed under the trade names of FirePro, 
FirePro Xtinguish, and FireBan, is generated in an automated 
manufacturing process during which the chemicals, in powder form, are 
mixed and then supplied to end users as a solid contained within a fire 
extinguisher. In the presence of heat, the solid converts to an aerosol 
consisting mainly of potassium salts. EPA listed Powdered Aerosol E as 
acceptable, subject to use conditions, as a total flooding agent (71 FR 
56359, September 27, 2006). The use conditions required that Powdered 
Aerosol E be used only in areas that are normally unoccupied, because 
the Agency did not have sufficient information at that time supporting 
its safe use in areas that are normally occupied. Based on a review of 
additional information from the submitter to support the safe use of 
Powdered Aerosol E in normally occupied spaces, EPA subsequently 
determined that Powdered Aerosol E is also acceptable for use in total 
flooding systems for normally occupied spaces (83 FR 50026, October 4, 
2018). The listing provides that Powdered Aerosol E is acceptable for 
total flooding uses, which includes both unoccupied and occupied 
spaces. In the October 2018 listing action, EPA noted that in a 
subsequent rulemaking, the Agency would remove the previous listing of 
Powdered Aerosol E as acceptable, subject to use conditions since the 
use condition is no longer applicable. We received no comments on the 
proposal for this listing. Therefore, in this final rule, as proposed, 
EPA is taking the ministerial action of removing that listing for 
Powdered Aerosol E.

III. How is EPA responding to other public comments?

    EPA received other comments beyond the scope of this final action 
and addresses them below.
    Comment: EIA stated ``that ODS are still undergoing replacement in 
the residential and light commercial AC and heat pump end-use and are 
subject to EPA's authority under the SNAP Program. EIA urges EPA to 
promulgate additional SNAP Program regulations listing high-GWP 
substitutes that pose a considerably higher comparable risk to the five 
refrigerant blends, as unacceptable for this end-use, including R-410A, 
R-404A, R-134a, and R-434A.''
    Response: This final rule lists additional substitutes as 
acceptable, subject to use conditions, in the residential and light 
commercial air conditioning end-use. The proposed rule did not discuss 
finding other substitutes unacceptable in this end-use and such 
listings are out of scope for this action. Accordingly, this comment 
requires no further response.
    Comment: EIA noted EPA's ``Ongoing Responsibility to Protect Global 
Ozone'' as it relates to methylene chloride 
(CH2Cl2). The commenter stated that the 
atmospheric concentrations of very short-lived substances (VSLS) 
including methylene chloride are increasing and that they are 
``increasingly seen as a threat to the progress made by the Montreal 
Protocol . . . to protect the ozone layer.'' In order to address this 
threat, EIA asks that the agency consider listing methylene chloride 
and other similar VSLS as unacceptable in some end-uses.
    Response: We appreciate EIA's comments on VSLS and note that EPA 
has taken domestic action on methylene chloride under the Toxic 
Substances Control Act (TSCA) due to its toxicity (84 FR 11420, March 
27, 2019). The proposed rule did not discuss listing VSLS as 
unacceptable and such listings are out of scope for this final action. 
Accordingly, this comment requires no further response.
    Comment: Trane commented that HFC-32, R-452B, and R-454B should 
also be approved for scroll chillers. AHRI requested EPA to find HFC-32 
and R-454B acceptable for positive displacement chillers, and Rheem 
similarly asked that SNAP list group A2L refrigerants in such 
equipment. Johnson Controls suggested listing HFC-32 and all five 
blends acceptable for positive displacement chillers, to include 
reciprocating, screw and scroll chillers. The Alliance, Carrier, and 
Chemours agreed and encouraged listing HFC-32 and the five A2L blends 
acceptable in chillers in general. Carrier pointed out that for 
chillers, requirements for machine rooms would be needed and held that 
the ASHRAE 15 standard could serve this purpose.
    Response: EPA notes that five of these six refrigerants (HFC-32, R-
452B, R-454A, R-454B, and R-454C) have been submitted to the SNAP 
program for use in chillers and EPA is evaluating them for the chiller 
end-use, encompassing both the centrifugal chiller and positive 
displacement chiller end-uses. The other refrigerant, R-457A, has been 
submitted but not for the chiller end-uses. The proposed rule addressed 
listings for certain end-use categories, which did not include the 
chiller end-use. The proposed rule did not discuss finding these 
substitutes acceptable in other end uses, and such listings are out of 
scope for this action. Accordingly, this comment requires no further 
response.
    Comment: Rheem sought clarification as to which SNAP end-use Heat 
Pump Pool Heaters (HPPH) and Heat Pump Water Heaters (HPWH) belong in 
and for clarification as to whether an end use category currently 
exists for these types of equipment.
    Response: The classification of HPPHs and HPWHs is beyond the scope 
of this final rule. Accordingly, this comment requires no further 
response. Nonetheless, EPA is now aware of this clarification request 
and we invite Rheem and other manufacturers of such equipment to 
further pursue this issue separately with EPA and the SNAP program.

IV. Statutory and Executive Order Reviews

A. Executive Order 12866: Regulatory Planning and Review and Executive 
Order 13563: Improving Regulation and Regulatory Review

    This action is not a significant regulatory action and was 
therefore not submitted to the Office of Management and Budget (OMB) 
for review.

[[Page 24470]]

B. Paperwork Reduction Act (PRA)

    This action does not impose any new information collection burden 
under the PRA. OMB has previously approved the information collection 
activities contained in the existing regulations and has assigned OMB 
control number 2060-0226. The approved Information Collection Request 
includes five types of respondent reporting and recordkeeping 
activities pursuant to SNAP regulations: Submission of a SNAP petition, 
filing a TSCA/SNAP Addendum, notification for test marketing activity, 
recordkeeping for substitutes acceptable subject to use restrictions, 
and recordkeeping for small volume uses. This rule contains no new 
requirements for reporting or recordkeeping.

C. Regulatory Flexibility Act (RFA)

    I certify that this action will not have a significant economic 
impact on a substantial number of small entities under the RFA. In 
making this determination, the impact of concern is any significant 
adverse economic impact on small entities. An agency may certify that a 
rule will not have a significant economic impact on a substantial 
number of small entities if the rule relieves regulatory burden, has no 
net burden or otherwise has a positive economic effect on the small 
entities subject to the rule. This action allows the additional options 
under SNAP of using R-32, R-448A, R-449A, R-449B, R-452B, R-454A, R-
454B, R-454C, and R-457A in the specified end-uses, but does not 
mandate such use. Users who choose to avail themselves of this 
flexibility for R-448A, R-449A, and R-449B must make a reasonable 
effort to ascertain that other substitutes or alternatives are not 
technically feasible and must document and keep records of the results 
of such investigations. Because equipment for R-452B, R-454A, R-454B, 
R-454C, and R-457A is not manufactured yet in the U.S. for the 
residential and light commercial air conditioning and heat pumps end-
use, no change in business practice is required to meet the use 
conditions, resulting in no adverse impact compared to the absence of 
this rule. Equipment for R-32 already being manufactured has been 
subject to similar use conditions, resulting in no adverse impact 
compared to the absence of this rule. Thus, this final rule would not 
impose new costs on small entities. We have therefore concluded that 
this action will not impose a significant adverse regulatory burden for 
all directly regulated small entities.

D. Unfunded Mandates Reform Act (UMRA)

    This action does not contain any unfunded mandate as described in 
UMRA, 2 U.S.C. 1531-1538, and does not significantly or uniquely affect 
small governments. The action imposes no enforceable duty on any state, 
local, or tribal governments or the private sector.

E. Executive Order 13132: Federalism

    This action does not have federalism implications. It will not have 
substantial direct effects on the states, on the relationship between 
the National Government and the states, or on the distribution of power 
and responsibilities among the various levels of government.

F. Executive Order 13175: Consultation and Coordination With Indian 
Tribal Governments

    This action does not have tribal implications as specified in 
Executive Order 13175. It will not have substantial direct effects on 
tribal governments, on the relationship between the Federal Government 
and Indian tribes, or on the distribution of power and responsibilities 
between the Federal Government and Indian tribes, as specified in 
Executive Order 13175.
    Thus, Executive Order 13175 does not apply to this action. EPA 
periodically updates tribal officials on air regulations through the 
monthly meetings of the National Tribal Air Association and will share 
information on this rulemaking through this and other fora.

G. Executive Order 13045: Protection of Children From Environmental 
Health and Safety Risks

    This action is not subject to Executive Order 13045 because it is 
not economically significant as defined in Executive Order 12866 and 
because EPA does not believe the environmental health or safety risks 
addressed by this action present a disproportionate risk to children. 
EPA has not conducted a separate analysis of risks to infants and 
children associated with this rule. Any risks to children are not 
different than the risks to the general population. This action's 
health and risk assessments are contained in the comparisons of 
toxicity for the various substitutes, as well as in the risk screens 
for the substitutes that are listed in this final rule. The risk 
screens are in the docket for this rulemaking.

H. Executive Order 13211: Actions That Significantly Affect Energy 
Supply, Distribution, or Use

    This action is not subject to Executive Order 13211, because it is 
not a significant regulatory action under Executive Order 12866.

I. National Technology Transfer and Advancement Act

    This action involves technical standards. EPA uses and incorporates 
by reference portions of the 2019 UL Standard 60335-2-40, which 
establishes requirements for the evaluation of residential air 
conditioning equipment and safe use of flammable refrigerants, among 
other things. The standard is discussed in greater detail in section 
II.B.5 of this preamble.
    The 2019 UL Standard 60335-2-40 is available at https://www.shopulstandards.com/ProductDetail.aspx?UniqueKey=36463, and may be 
purchased by mail at: Comm 2000, 151 Eastern Avenue, Bensenville, IL 
60106; Email: orders@shopulstandards.com; Telephone: 1-888-853-3503 in 
the U.S. or Canada (other countries dial 1-415-352-2178); internet 
address: https://www.shopulstandards.com. The cost of the 2019 UL 
Standard 60335-2-40 is $440 for an electronic copy and $550 for 
hardcopy. UL also offers a subscription service to the Standards 
Certification Customer Library that allows unlimited access to their 
standards and related documents. The cost of obtaining this standard is 
not a significant financial burden for equipment manufacturers and 
purchase is not necessary for those selling, installing, and servicing 
the equipment. Therefore, EPA concludes that the UL standard 
incorporated by reference is reasonably available.

J. Executive Order 12898: Federal Actions To Address Environmental 
Justice in Minority Populations and Low-Income Population

    EPA believes that it is not feasible to quantify any 
disproportionately high and adverse human health or environmental 
effects from this action on minority populations, low-income 
populations and/or indigenous peoples, as specified in Executive Order 
12898 (59 FR 7629, February 16, 1994) because for all affected 
populations there is no requirement to use any of the alternatives 
listed in this action.

K. Congressional Review Act (CRA)

    This action is subject to the CRA, and EPA will submit a rule 
report to each House of the Congress and to the Comptroller General of 
the United States. This action is not a ``major rule'' as defined by 5 
U.S.C. 804(2).

[[Page 24471]]

V. References

    Unless specified otherwise, all documents are available 
electronically through the Federal Docket Management System, Docket 
number EPA-HQ-OAR-2019-0698.

AHRI, 2017. Petition Requesting EPA SNAP Approval of R-448A/449A/
449B for Medium Temperature, Stand-Alone Retail Food Refrigeration 
Equipment. Submitted March 20, 2017.
ASHRAE, 2019. ANSI/ASHRAE Standard 34-2019: Designation and Safety 
Classification of Refrigerants.
Cousins, et al., 2019. Cousins, I.T., Goldenman G., Herzke, D., 
Lohmann, R., Miller, M., Ng, C.A., Patton, S., Scheringer, M., 
Trier, X., Vierke, L., Wang, Z., and DeWitt, J.C. (2019). The 
concept of essential use for determining when uses of PFASs can be 
phased out. Environ. Sci.: Processes Impacts, 2019, 21, 1803-1815. 
Available online at: https://pubs.rsc.org/en/content/articlelanding/2019/em/c9em00163h#!divAbstract.
Hodnebrog, et al., 2013. Hodnebrog, [Oslash]., Etminan, M., 
Fuglestvedt, J.S., Marston, G., Myhre, G., Nielsen, C.J., Shine, 
K.P., and Wallington, T.J. (2013). Global Warming Potentials and 
Radiative Efficiencies of Halocarbons and Related Compounds: A 
Comprehensive Review, Reviews of Geophysics, 51, 300-378. Available 
online at doi.org/10.1002/rog.20013.
ICF, 2020a. Risk Screen on Substitutes in Retail Food Refrigeration 
(Medium-temperature Stand-alone Units) (New Equipment); Substitute: 
R-448A.
ICF, 2020b. Risk Screen on Substitutes in Retail Food Refrigeration 
(Medium-temperature Stand-alone Units) (New Equipment); Substitute: 
R-449A.
ICF, 2020c. Risk Screen on Substitutes in Retail Food Refrigeration 
(Medium-temperature Stand-alone Units) (New Equipment); Substitute: 
R-449B.
ICF, 2020d. Risk Screen on Substitutes in Residential and Light 
Commercial Air-Conditioning and Heat Pumps (New Equipment); 
Substitute: HFC-32.
ICF, 2020e. Risk Screen on Substitutes in Residential and Light 
Commercial Air-Conditioning and Heat Pumps (New Equipment); 
Substitute: R-452B.
ICF, 2020f. Risk Screen on Substitutes in Residential and Light 
Commercial Air-Conditioning and Heat Pumps (New Equipment); 
Substitute: R-454A.
ICF, 2020g. Risk Screen on Substitutes in Residential and Light 
Commercial Air-Conditioning and Heat Pumps (New Equipment); 
Substitute: R-454B.
ICF, 2020h. Risk Screen on Substitutes in Residential and Light 
Commercial Air-Conditioning and Heat Pumps (New Equipment); 
Substitute: R-454C.
ICF, 2020i. Risk Screen on Substitutes in Residential and Light 
Commercial Air-Conditioning and Heat Pumps (New Equipment); 
Substitute: R-457A.
IPCC, 2007. Climate Change 2007: The Physical Science Basis. 
Contribution of Working Group I to the Fourth Assessment Report of 
the Intergovernmental Panel on Climate Change. Solomon, S., Qin, D., 
Manning, M., Chen, Z., Marquis, M., Averyt, K.B., Tignor, M., and 
Miller, H.L. (eds.). Cambridge University Press. Cambridge, United 
Kingdom and New York, NY, USA. Available online at: www.ipcc.ch/
publications_and_data/ar4/wg1/en/contents.html.
Javadi et al., 2008. Javadi, M.S., S[oslash]ndergaard, R., Nielsen, 
O.J., Hurley, M.D., and Wellington, T.J., (2008). Atmospheric 
chemistry of trans-CF3CH=CHF: products and mechanisms of hydroxyl 
radical and chlorine atom-initiated oxidation. Atmospheric Chemistry 
and Physics Discussions 8, 1069-1088. Available online at https://www.atmos-chem-phys.net/8/3141/2008/.
Kwiatkowski et al. 2020. Kwiatkowski, C.F., Andrews, D.Q., Birnbaum, 
L.S., Bruton, T.A., DeWitt, J.C., Knappe, D.R.U., Maffini, M.V., 
Miller, M.F., Pelch, K.E., Reade, A., Soehl, A., Trier, X., Venier, 
M., Wagner, C.C., Wang, Z., and Blum, A. (2020). Scientific Basis 
for Managing PFAS as a Chemical Class. Environ. Sci. Technol. Lett. 
2020, 7, 532-543. Available online at: https://pubs.acs.org/doi/10.1021/acs.estlett.0c00255.
Nielsen et al., 2007. Nielsen, O.J., Javadi, M.S., Sulbaek Andersen, 
M.P., Hurley, M.D., Wallington, T.J., Singh, R. (2007). Atmospheric 
chemistry of CF3CF=CH2: Kinetics and mechanisms of gas-phase 
reactions with Cl atoms, OH radicals, and O3. Chemical Physics 
Letters 439, 18-22. Available online at http://www.lexissecuritiesmosaic.com/gateway/FedReg/network_OJN_174_CF3CF=CH2.pdf.
The Air Conditioning, Heating, and Refrigeration News, 2020. ``An 
HVAC Technician's Guide to R-32,'' November 12, 2020. Available 
online at: https://www.achrnews.com/articles/144053-an-hvac-technicians-guide-to-r-32?oly_enc_id=8731J4776701J6C
UL 60335-2-40, 2019. Standard for Safety for Household And Similar 
Electrical Appliances--Safety--Part 2-40: Particular Requirements 
for Electrical Heat Pumps, Air-Conditioners and Dehumidifiers. Third 
Edition. November 1, 2019.

List of Subjects in 40 CFR Part 82

    Environmental protection, Administrative practice and procedure, 
Air pollution control, Incorporation by reference, Reporting and 
recordkeeping requirements, Stratospheric ozone layer.

Michael S. Regan,
Administrator.

    For the reasons set forth in the preamble, EPA amends 40 CFR part 
82 as follows:

PART 82--PROTECTION OF STRATOSPHERIC OZONE

0
1. The authority citation for part 82 continues to read as follows:

    Authority:  42 U.S.C. 7414, 7601, 7671-7671q.

Subpart G--Significant New Alternatives Policy Program

Appendix O to Subpart G of Part 82 [Amended]

0
2. Appendix O to subpart G of part 82 is amended by removing the entry 
``Total flooding; Powdered Aerosol E (FirePro[supreg])''.

[[Page 24472]]

0
3. Add appendix W to subpart G of part 82 to read as follows:

Appendix W to Subpart G of Part 82--Substitutes Listed in the May 6, 
2021 Final Rule--Effective June 7, 2021

                                           Refrigerants--Substitutes Acceptable Subject to Narrowed Use Limits
--------------------------------------------------------------------------------------------------------------------------------------------------------
              End-use                      Substitute               Decision                   Narrowed use limits                Further information
--------------------------------------------------------------------------------------------------------------------------------------------------------
Retail food refrigeration-- medium-  R-448A, R-449A, R-449B  Acceptable Subject to   Acceptable only for use in new medium-   A possible reason for
 temperature stand-alone units (new                           Narrowed Use Limits.    temperature stand-alone units where      rejection of one or more
 only).                                                                               reasonable efforts have been made to     other alternative(s)
                                                                                      ascertain that other alternatives are    could be based on ADA
                                                                                      not technically feasible.                requirements.
                                                                                     Users are required to document and
                                                                                      retain the results of their technical
                                                                                      investigation of alternatives for the
                                                                                      purpose of demonstrating compliance.
                                                                                     Information shall include descriptions
                                                                                      of:
                                                                                         Process or product in which
                                                                                         the substitute is needed;
                                                                                         Substitutes examined and
                                                                                         rejected;
                                                                                         Reason for rejection of
                                                                                         other alternatives, e.g.,
                                                                                         performance, technical or safety
                                                                                         standards; and
                                                                                         Anticipated date other
                                                                                         substitutes will be available and
                                                                                         projected time for switching.
--------------------------------------------------------------------------------------------------------------------------------------------------------

                                             Refrigerants--Substitutes Acceptable Subject to Use Conditions
--------------------------------------------------------------------------------------------------------------------------------------------------------
              End-use                      Substitute               Decision                      Use conditions                  Further information
--------------------------------------------------------------------------------------------------------------------------------------------------------
Residential and light commercial     R-452B, R-454A, R-      Acceptable Subject to   These refrigerants may be used only in   Applicable OSHA
 air conditioning and heat pumps      454B, R-454C and R-     Use Conditions.         new equipment specifically designed      requirements at 29 CFR
 (new only).                          457A.                                           and clearly identified for the           part 1910 must be
                                                                                      refrigerants (i.e., none of these        followed, including those
                                                                                      substitutes may be used as a             at 29 CFR 1910.94
                                                                                      conversion or ``retrofit'' refrigerant   (ventilation) and
                                                                                      for existing equipment designed for      1910.106 (flammable and
                                                                                      other refrigerants).                     combustible liquids),
                                                                                     These substitutes may only be used in     1910.110 (storage and
                                                                                      air conditioning equipment that meets    handling of liquefied
                                                                                      all requirements in the 3rd edition of   petroleum gases), and
                                                                                      UL 60335-2-40. 1 2 3 In cases where      1910.1000 (toxic and
                                                                                      this appendix includes requirements      hazardous substances).
                                                                                      more stringent than those of UL 60335-  Proper ventilation should
                                                                                      2-40, the appliance must meet the        be maintained at all
                                                                                      requirements of this appendix in place   times during the
                                                                                      of the requirements in the UL            manufacture and storage
                                                                                      Standard.                                of equipment containing
                                                                                     The charge size for the equipment must    flammable refrigerants
                                                                                      not exceed the maximum refrigerant       through adherence to good
                                                                                      mass determined according to UL 60335-   manufacturing practices
                                                                                      2-40 for the room size where the air     as per 29 CFR 1910.106.
                                                                                      conditioner is used.                     If refrigerant levels in
                                                                                                                               the air surrounding the
                                                                                                                               equipment rise above one-
                                                                                                                               fourth of the lower
                                                                                                                               flammability limit, the
                                                                                                                               space should be evacuated
                                                                                                                               and reentry should occur
                                                                                                                               only after the space has
                                                                                                                               been properly ventilated.
                                                                                     The following markings must be attached  Technicians and equipment
                                                                                      at the locations provided and must be    manufacturers should wear
                                                                                      permanent:                               appropriate personal
                                                                                     (a) On the outside of the air             protective equipment,
                                                                                      conditioning equipment: ``WARNING--      including chemical
                                                                                      Risk of Fire. Flammable Refrigerant      goggles and protective
                                                                                      Used. To Be Repaired Only By Trained     gloves, when handling
                                                                                      Service Personnel. Do Not Puncture       flammable refrigerants.
                                                                                      Refrigerant Tubing.''                    Special care should be
                                                                                     (b) On the outside of the air             taken to avoid contact
                                                                                      conditioning equipment: ``WARNING--      with the skin which, like
                                                                                      Risk of Fire. Dispose of Properly In     many refrigerants, can
                                                                                      Accordance With Federal Or Local         cause freeze burns on the
                                                                                      Regulations. Flammable Refrigerant       skin.
                                                                                      Used.''                                 A class B dry powder type
                                                                                     (c) On the inside of the air              fire extinguisher should
                                                                                      conditioning equipment near the          be kept nearby.
                                                                                      compressor: ``WARNING--Risk of Fire.    Technicians should only
                                                                                      Flammable Refrigerant Used. Consult      use spark-proof tools
                                                                                      Repair Manual/Owner's Guide Before       when working on air
                                                                                      Attempting To Service This Product.      conditioning equipment
                                                                                      All Safety Precautions Must be           with flammable
                                                                                      Followed.''                              refrigerants.
                                                                                     (d) For any equipment pre-charged at     Any recovery equipment
                                                                                      the factory, on the equipment            used should be designed
                                                                                      packaging: ``WARNING--Risk of Fire due   for flammable
                                                                                      to Flammable Refrigerant Used. Follow    refrigerants. Only
                                                                                      Handling Instructions Carefully in       technicians specifically
                                                                                      Compliance with National                 trained in handling
                                                                                      Regulations.''                           flammable refrigerants
                                                                                     (e) On the indoor unit near the           should service
                                                                                      nameplate:                               refrigeration equipment
                                                                                     a. At the top of the marking: ``Minimum   containing these
                                                                                      Installation height, X m (W ft)''.       refrigerants. Technicians
                                                                                      This marking is only required if         should gain an
                                                                                      required by UL 60335-2-40. The terms     understanding of
                                                                                      ``X'' and ``W'' shall be replaced by     minimizing the risk of
                                                                                      the numeric height as calculated per     fire and the steps to use
                                                                                      the UL Standard. Note that the           flammable refrigerants
                                                                                      formatting here is slightly different    safely.
                                                                                      than the UL Standard; specifically,     Room occupants should
                                                                                      the height in Inch-Pound units is        evacuate the space
                                                                                      placed in parentheses and the word       immediately following the
                                                                                      ``and'' has been replaced by the         accidental release of
                                                                                      opening parenthesis.                     this refrigerant.
                                                                                     b. Immediately below (a) above or at     Personnel commissioning,
                                                                                      the top of the marking if (a) is not     maintaining, repairing,
                                                                                      required: ``Minimum room area            decommissioning and
                                                                                      (operating or storage), Y m\2\ (Z        disposing of appliances
                                                                                      ft\2\)''. The terms ``Y'' and ``Z''      with these refrigerants
                                                                                      shall be replaced by the numeric area    should obtain training
                                                                                      as calculated per the UL Standard.       and follow practices
                                                                                      Note that the formatting here is         consistent with Annex HH
                                                                                      slightly different than the UL           of UL 60335-2-40, 3rd
                                                                                      Standard; specifically, the area in      edition.1 2 3
                                                                                      Inch-Pound units is placed in           CAA section 608(c)(2)
                                                                                      parentheses and the word ``and'' has     prohibits knowingly
                                                                                      been replaced by the opening             venting or otherwise
                                                                                      parenthesis.                             knowingly releasing or
                                                                                                                               disposing of substitute
                                                                                                                               refrigerants in the
                                                                                                                               course of maintaining,
                                                                                                                               servicing, repairing or
                                                                                                                               disposing of an appliance
                                                                                                                               or industrial process
                                                                                                                               refrigeration.
                                                                                                                              Department of
                                                                                                                               Transportation
                                                                                                                               requirements for
                                                                                                                               transport of flammable
                                                                                                                               gases must be followed.
                                                                                                                              Flammable refrigerants
                                                                                                                               being recovered or
                                                                                                                               otherwise disposed of
                                                                                                                               from residential and
                                                                                                                               light commercial air
                                                                                                                               conditioning appliances
                                                                                                                               are likely to be
                                                                                                                               hazardous waste under the
                                                                                                                               Resource Conservation and
                                                                                                                               Recovery Act (RCRA) (see
                                                                                                                               40 CFR parts 260-270).

[[Page 24473]]

 
                                                                                        (f) For non-fixed equipment,
                                                                                         including portable air
                                                                                         conditioners, window air
                                                                                         conditioners, packaged terminal air
                                                                                         conditioners and packaged terminal
                                                                                         heat pumps, on the outside of the
                                                                                         product: ``WARNING--Risk of Fire or
                                                                                         Explosion--Store in a well
                                                                                         ventilated room without
                                                                                         continuously operating flames or
                                                                                         other potential ignition.''
                                                                                        (g) For fixed equipment, including
                                                                                         rooftop units and split air
                                                                                         conditioners, ``WARNING--Risk of
                                                                                         Fire--Auxiliary devices which may
                                                                                         be ignition sources shall not be
                                                                                         installed in the ductwork, other
                                                                                         than auxiliary devices listed for
                                                                                         use with the specific appliance.
                                                                                         See instructions.''
                                                                                        (h) All of these markings must be in
                                                                                         letters no less than 6.4 mm (\1/4\
                                                                                         inch) high.
                                                                                     The equipment must have red Pantone
                                                                                      Matching System (PMS) #185 or RAL 3020
                                                                                      marked service ports, pipes, hoses, or
                                                                                      other devices through which the
                                                                                      refrigerant passes, to indicate the
                                                                                      use of a flammable refrigerant. This
                                                                                      color must be applied at all service
                                                                                      ports and other parts of the system
                                                                                      where service puncturing or other
                                                                                      actions creating an opening from the
                                                                                      refrigerant circuit to the atmosphere
                                                                                      might be expected and must extend a
                                                                                      minimum of one (1) inch (25mm) in both
                                                                                      directions from such locations and
                                                                                      shall be replaced if removed.
Residential and light commercial     R-32..................  Acceptable Subject to   These refrigerants may be used only in   Applicable OSHA
 air conditioning and heat pumps                              Use Conditions.         new equipment specifically designed      requirements at 29 CFR
 (new only), excluding self-                                                          and clearly identified for the           part 1910 must be
 contained room air conditioners.                                                     refrigerants (i.e., none of these        followed, including those
                                                                                      substitutes may be used as a             at 29 CFR 1910.94
                                                                                      conversion or ``retrofit'' refrigerant   (ventilation) and
                                                                                      for existing equipment designed for      1910.106 (flammable and
                                                                                      other refrigerants).                     combustible liquids),
                                                                                     These substitutes may only be used in     1910.110 (storage and
                                                                                      air conditioning equipment that meets    handling of liquefied
                                                                                      all requirements in the 3rd edition of   petroleum gases), and
                                                                                      UL 60335-2-40.1 2 3 In cases where       1910.1000 (toxic and
                                                                                      this appendix includes requirements      hazardous substances).
                                                                                      more stringent than those of UL 60335-  Proper ventilation should
                                                                                      2-40, the appliance must meet the        be maintained at all
                                                                                      requirements of this appendix in place   times during the
                                                                                      of the requirements in the UL            manufacture and storage
                                                                                      Standard.                                of equipment containing
                                                                                     The charge size for the equipment must    flammable refrigerants
                                                                                      not exceed the maximum refrigerant       through adherence to good
                                                                                      mass determined according to UL 60335-   manufacturing practices
                                                                                      2-40 for the room size where the air     as per 29 CFR 1910.106.
                                                                                      conditioner is used.                     If refrigerant levels in
                                                                                                                               the air surrounding the
                                                                                                                               equipment rise above one-
                                                                                                                               fourth of the lower
                                                                                                                               flammability limit, the
                                                                                                                               space should be evacuated
                                                                                                                               and reentry should occur
                                                                                                                               only after the space has
                                                                                                                               been properly ventilated.
                                                                                     The following markings must be attached  Technicians and equipment
                                                                                      at the locations provided and must be    manufacturers should wear
                                                                                      permanent:                               appropriate personal
                                                                                     (a) On the outside of the air             protective equipment,
                                                                                      conditioning equipment: ``WARNING--      including chemical
                                                                                      Risk of Fire. Flammable Refrigerant      goggles and protective
                                                                                      Used. To Be Repaired Only By Trained     gloves, when handling
                                                                                      Service Personnel. Do Not Puncture       flammable refrigerants.
                                                                                      Refrigerant Tubing.''                    Special care should be
                                                                                     (b) On the outside of the air             taken to avoid contact
                                                                                      conditioning equipment: ``WARNING--      with the skin which, like
                                                                                      Risk of Fire. Dispose of Properly In     many refrigerants, can
                                                                                      Accordance With Federal Or Local         cause freeze burns on the
                                                                                      Regulations. Flammable Refrigerant       skin.
                                                                                      Used.''                                 A class B dry powder type
                                                                                     (c) On the inside of the air              fire extinguisher should
                                                                                      conditioning equipment near the          be kept nearby.
                                                                                      compressor: ``WARNING--Risk of Fire.    Technicians should only
                                                                                      Flammable Refrigerant Used. Consult      use spark-proof tools
                                                                                      Repair Manual/Owner's Guide Before       when working on air
                                                                                      Attempting To Service This Product.      conditioning equipment
                                                                                      All Safety Precautions Must be           with flammable
                                                                                      Followed.''                              refrigerants.
                                                                                     (d) For any equipment pre-charged at     Any recovery equipment
                                                                                      the factory, on the equipment            used should be designed
                                                                                      packaging: ``WARNING--Risk of Fire due   for flammable
                                                                                      to Flammable Refrigerant Used. Follow    refrigerants. Only
                                                                                      Handling Instructions Carefully in       technicians specifically
                                                                                      Compliance with National Regulations''   trained in handling
                                                                                     (e) On the indoor unit near the           flammable refrigerants
                                                                                      nameplate:                               should service
                                                                                     a. At the top of the marking: ``Minimum   refrigeration equipment
                                                                                      Installation height, X m (W ft)''.       containing this
                                                                                      This marking is only required if         refrigerant. Technicians
                                                                                      required by UL 60335-2-40. The terms     should gain an
                                                                                      ``X'' and ``W'' shall be replaced by     understanding of
                                                                                      the numeric height as calculated per     minimizing the risk of
                                                                                      the UL Standard. Note that the           fire and the steps to use
                                                                                      formatting here is slightly different    flammable refrigerants
                                                                                      than the UL Standard; specifically,      safely.
                                                                                      the height in Inch-Pound units is       Room occupants should
                                                                                      placed in parentheses and the word       evacuate the space
                                                                                      ``and'' has been replaced by the         immediately following the
                                                                                      opening parenthesis.                     accidental release of
                                                                                     b. Immediately below (a) above or at      this refrigerant.
                                                                                      the top of the marking if (a) is not    Personnel commissioning,
                                                                                      required: ``Minimum room area            maintaining, repairing,
                                                                                      (operating or storage), Y m\2\ (Z        decommissioning and
                                                                                      ft\2\)''. The terms ``Y'' and ``Z''      disposing of appliances
                                                                                      shall be replaced by the numeric area    with this refrigerant
                                                                                      as calculated per the UL Standard.       should obtain training
                                                                                      Note that the formatting here is         and follow practices
                                                                                      slightly different than the UL           consistent with Annex HH
                                                                                      Standard; specifically, the area in      of UL 60335-2-40, 3rd
                                                                                      Inch-Pound units is placed in            edition.\1\ \2\ \3\
                                                                                      parentheses and the word ``and'' has    CAA section 608(c)(2)
                                                                                      been replaced by the opening             prohibits knowingly
                                                                                      parenthesis.                             venting or otherwise
                                                                                                                               knowingly releasing or
                                                                                                                               disposing of substitute
                                                                                                                               refrigerants in the
                                                                                                                               course of maintaining,
                                                                                                                               servicing, repairing or
                                                                                                                               disposing of an appliance
                                                                                                                               or industrial process
                                                                                                                               refrigeration.
                                                                                                                              Department of
                                                                                                                               Transportation
                                                                                                                               requirements for
                                                                                                                               transport of flammable
                                                                                                                               gases must be followed.
                                                                                                                              Flammable refrigerants
                                                                                                                               being recovered or
                                                                                                                               otherwise disposed of
                                                                                                                               from residential and
                                                                                                                               light commercial air
                                                                                                                               conditioning appliances
                                                                                                                               are likely to be
                                                                                                                               hazardous waste under the
                                                                                                                               Resource Conservation and
                                                                                                                               Recovery Act (RCRA) (see
                                                                                                                               40 CFR parts 260-270).
                                                                                        (f) For fixed equipment, including
                                                                                         rooftop units and split air
                                                                                         conditioners, ``WARNING--Risk of
                                                                                         Fire--Auxiliary devices which may
                                                                                         be ignition sources shall not be
                                                                                         installed in the ductwork, other
                                                                                         than auxiliary devices listed for
                                                                                         use with the specific appliance.
                                                                                         See instructions.''
                                                                                        (g) All of these markings must be in
                                                                                         letters no less than 6.4 mm (\1/4\
                                                                                         inch) high.

[[Page 24474]]

 
                                                                                        The equipment must have red Pantone
                                                                                         Matching System (PMS) #185 or RAL
                                                                                         3020 marked service ports, pipes,
                                                                                         hoses, or other devices through
                                                                                         which the refrigerant passes, to
                                                                                         indicate the use of a flammable
                                                                                         refrigerant. This color must be
                                                                                         applied at all service ports and
                                                                                         other parts of the system where
                                                                                         service puncturing or other actions
                                                                                         creating an opening from the
                                                                                         refrigerant circuit to the
                                                                                         atmosphere might be expected and
                                                                                         must extend a minimum of one (1)
                                                                                         inch (25mm) in both directions from
                                                                                         such locations and shall be
                                                                                         replaced if removed.
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ UL 60335-2-40, Standard for Safety for Household And Similar Electrical Appliances--Safety--Part 2-40: Particular Requirements for Electrical Heat
  Pumps, Air-Conditioners and Dehumidifiers, Third edition, Dated November 1, 2019.
\2\ You may purchase the material from UL by mail: Comm 2000; 151 Eastern Avenue; Bensenville, IL 60106; email: orders@shopulstandards.com; phone: 1-888-
  853-3503 in the U.S. or Canada (other countries dial +1-415-352-2168); or web: www.shopulstandards.com.
\3\ The Director of the Federal Register approves this incorporation by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. All approved
  material is available for inspection at U.S. EPA's Air and Radiation Docket; EPA West Building, Room 3334, 1301 Constitution Ave. NW, Washington, DC,
  202-566-1742 and is available from Underwriters Laboratories Inc. (UL), 333 Pfingsten Road, Northbrook, IL 60062, 877.854.3577, www.ul.com. It is also
  available for inspection at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA,
  email fedreg.legal@nara.gov, or go to: www.archives.gov/federal-register/cfr/ibr-locations.html.

[FR Doc. 2021-08968 Filed 5-5-21; 8:45 am]
BILLING CODE 6560-50-P