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Rule2026-10387

Phasedown of Hydrofluorocarbons: Reconsideration of Certain Regulatory Requirements Promulgated Under the Technology Transitions Provisions of the American Innovation and Manufacturing Act of 2020

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Published

May 26, 2026

Effective

July 27, 2026

Issuing agencies

Environmental Protection Agency

Abstract

The U.S. Environmental Protection Agency (EPA) is finalizing changes to regulations promulgated under the Technology Transitions provision of the American Innovation and Manufacturing Act of 2020 (AIM Act), which authorizes the Administrator to restrict fully, partially, or on a graduated schedule, the use of a "regulated substance" in the sector or subsector in which they are used. This final rule addresses administrative petitions and input received from regulated industry and other interested parties relevant to requirements and restrictions across various refrigeration and air conditioning subsectors, including: refrigerated transport--intermodal containers; industrial process refrigeration and chillers for industrial process refrigeration used in semiconductor manufacturing; retail food supermarket systems; retail food remote condensing unit systems; cold storage warehouses; refrigerated laboratory centrifuges and laboratory shakers; and condensing units in residential and light commercial air conditioning and heat pumps. This final rule also allows the inventory of residential and light commercial air conditioning and heat pump equipment that was manufactured in the United States or imported into the United States before January 1, 2025, to continue to be installed.

Full Text

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<title>Federal Register, Volume 91 Issue 100 (Tuesday, May 26, 2026)</title>
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[Federal Register Volume 91, Number 100 (Tuesday, May 26, 2026)]
[Rules and Regulations]
[Pages 31284-31330]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2026-10387]

[[Page 31283]]

Vol. 91

Tuesday,

No. 100

May 26, 2026

Part IV

Environmental Protection Agency

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40 CFR Part 84

Phasedown of Hydrofluorocarbons: Reconsideration of Certain Regulatory
Requirements Promulgated Under the Technology Transitions Provisions of
the American Innovation and Manufacturing Act of 2020; Final Rules

Federal Register / Vol. 91, No. 100 / Tuesday, May 26, 2026 / Rules
and Regulations

[[Page 31284]]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 84

[EPA-HQ-OAR-2025-0005; FRL-12166-02-OAR]
RIN 2060-AW39

Phasedown of Hydrofluorocarbons: Reconsideration of Certain
Regulatory Requirements Promulgated Under the Technology Transitions
Provisions of the American Innovation and Manufacturing Act of 2020

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: The U.S. Environmental Protection Agency (EPA) is finalizing
changes to regulations promulgated under the Technology Transitions
provision of the American Innovation and Manufacturing Act of 2020 (AIM
Act), which authorizes the Administrator to restrict fully, partially,
or on a graduated schedule, the use of a ``regulated substance'' in the
sector or subsector in which they are used. This final rule addresses
administrative petitions and input received from regulated industry and
other interested parties relevant to requirements and restrictions
across various refrigeration and air conditioning subsectors,
including: refrigerated transport--intermodal containers; industrial
process refrigeration and chillers for industrial process refrigeration
used in semiconductor manufacturing; retail food supermarket systems;
retail food remote condensing unit systems; cold storage warehouses;
refrigerated laboratory centrifuges and laboratory shakers; and
condensing units in residential and light commercial air conditioning
and heat pumps. This final rule also allows the inventory of
residential and light commercial air conditioning and heat pump
equipment that was manufactured in the United States or imported into
the United States before January 1, 2025, to continue to be installed.

DATES: This final rule is effective on July 27, 2026.

ADDRESSES: The EPA has established a docket for this action under
Docket ID No. EPA-HQ-OAR-2025-0005. All documents in the docket are
listed on the <a href="https://www.regulations.gov">https://www.regulations.gov</a> website. Although listed,
some information is not publicly available, e.g., Confidential Business
Information or other information whose disclosure is restricted by
statute. The EPA does not place certain other material, such as
copyrighted material, on the internet; this material is publicly
available only as Portable Document Format versions and accessible only
on the EPA computers in the docket office reading room. The public
cannot download certain databases and physical items from the docket
but may request these items by contacting the docket office by
telephone at (202) 566-1744. The docket office has 10 business days to
respond to such requests. Except for these items, publicly available
docket materials are available electronically at <a href="https://www.regulations.gov">https://www.regulations.gov</a> or on the EPA computers in the docket office
reading room at the EPA Docket Center, WJC West Building, Room Number
3334, 1301 Constitution Ave. NW, Washington, DC. The Public Reading
Room hours of operation are 8:30 a.m. to 4:30 p.m. Eastern Time, Monday
through Friday. The telephone number for the Public Reading Room is
(202) 566-1744.

FOR FURTHER INFORMATION CONTACT: For further information about this
final rule, contact Joshua Silver, Chemicals, Coatings, and Products
Division, Office of Clean Air Programs (Mail Code 6205A), Environmental
Protection Agency, 1200 Pennsylvania Ave. NW, Washington, DC 20460;
telephone number: (202) 564-2473; email address: <a href="/cdn-cgi/l/email-protection#22514b4e5447500c484d514a5743624752430c454d54"><span class="__cf_email__" data-cfemail="66150f0a100314480c09150e13072603160748010910">[email&#160;protected]</span></a>.
You may also visit the EPA's website at <a href="https://www.epa.gov/climate-hfcs-reduction">https://www.epa.gov/climate-hfcs-reduction</a> for further information.

SUPPLEMENTARY INFORMATION:
Preamble acronyms and abbreviations. Throughout this document,
whenever ``we,'' ``us,'' ``the Agency,'' or ``our'' is intended to
refer to the EPA. We use multiple acronyms and terms in this preamble.
While this list may not be exhaustive, to ease the reading of this
preamble and for reference purposes, the EPA defines the following
terms and acronyms here:

AC Air Conditioning
AC/HP Air Conditioning and Heat Pumps
AHJ Authority Having Jurisdiction
AHRI Air-Conditioning, Heating, and Refrigeration Institute
AIM Act American Innovation and Manufacturing Act of 2020
ANSI American National Standards Institute
APA Administrative Procedure Act
ASHRAE American Society of Heating, Refrigerating and Air-
Conditioning Engineers
BTU British Thermal Units
CAA Clean Air Act
CFR Code of Federal Regulations
CO<INF>2</INF> Carbon Dioxide
CRA Congressional Review Act
CUSER Coalition for the Use of Safe and Efficient Refrigerants, Inc.
EAV Equivalent Annualized Value
EPA U.S. Environmental Protection Agency
FMI Food Industry Association
FR Federal Register
GHG Greenhouse Gas
GWP Global Warming Potential
HARDI Heating, Air-Conditioning, and Refrigeration Distributors
International
HCFC Hydrochlorofluorocarbon
HFC Hydrofluorocarbon
HFO Hydrofluoroolefin
HVAC Heating, Ventilation, and Air Conditioning
IBC International Building Code
ICC International Code Council
IEBC International Existing Building Code
IFC International Fire Code
IFR Interim Final Rule
IMC International Mechanical Code
IPR Industrial Process Refrigeration
ISO International Organization for Standardization
MCA Maximum Credible Accident
MMTEVe Million Metric Tons of Exchange Value Equivalent
NAICS North American Industry Classification System
NFPA National Fire Protection Association
NTTAA National Technology Transfer and Advancement Act
ODS Ozone-Depleting Substance
OEM Original Equipment Manufacturer
OMB Office of Management and Budget
PFAS Per- and Polyfluoroalkyl Substances
PRA Paperwork Reduction Act
PV Present Value
RFA Regulatory Flexibility Act
RTC Response to Comments
SC-GHG Social Cost of Greenhouse Gases
SEMI Semiconductor Equipment and Materials International
SMRE Semiconductor Manufacturing and Related Equipment
SNAP Significant New Alternatives Policy
UL Underwriters Laboratories (formerly)
UMC Uniform Mechanical Code
UMRA Unfunded Mandates Reform Act
U.S.C. United States Code
VRF Variable Refrigerant Flow

Table of Contents

I. General Information
A. Executive Summary
B. Does this action apply to me?
II. Statutory Background and Regulatory History
A. What is the authority for this action?
B. Severability
C. Summary of 2023 Final Rule
D. Summary of 2023 Interim Final Rule
E. Summary of Administrative Petitions and Requests Related to
This Rulemaking
F. Judicial Review and Administrative Review
III. Summary of Final Action
A. Refrigerated Transport--Intermodal Containers
B. Industrial Process Refrigeration and Chillers for Industrial
Process Refrigeration in Semiconductor Manufacturing
C. Retail Food--Supermarkets
D. Retail Food--Remote Condensing Units
E. Cold Storage Warehouses
F. Replacement Condensing Units in the Residential and Light
Commercial Air Conditioning and Heat Pump Subsector

[[Page 31285]]

G. Industrial Process Refrigeration in Certain Laboratory
Equipment
H. Preventing Stranded Inventory of Residential and Light
Commercial Air Conditioning and Heat Pump Equipment
I. Labeling Correction
J. Effective Date of Rules Under Paragraph (i)(6)
IV. Comments and Responses
A. Refrigerated Transport--Intermodal Containers
B. Industrial Process Refrigeration and Chillers for Industrial
Process Refrigeration in Semiconductor Manufacturing
C. Retail Food--Supermarkets
D. Retail Food--Remote Condensing Units
E. Cold Storage Warehouses
F. Replacement Condensing Units in the Residential and Light
Commercial Air Conditioning and Heat Pump Subsector
G. Industrial Process Refrigeration in Certain Laboratory
Equipment
H. Preventing Stranded Inventory of Residential and Light
Commercial Air Conditioning and Heat Pump Equipment
I. Labeling Correction
J. Effective Date of Rules Under Paragraph (i)(6)
K. Other Comments and Responses
V. How do these final amendments impact the implementation of the
Technology Transitions Provisions?
VI. Statutory and Executive Order Reviews
A. Executive Order 12866: Regulatory Planning and Review and
Executive Order 13563: Improving Regulation and Regulatory Review
B. Executive Order 14192: Unleashing Prosperity Through
Deregulation
C. Paperwork Reduction Act (PRA)
D. Regulatory Flexibility Act (RFA)
E. Unfunded Mandates Reform Act (UMRA)
F. Executive Order 13132: Federalism
G. Executive Order 13175: Consultation and Coordination With
Indian Tribal Governments
H. Executive Order 13045: Protection of Children From
Environmental Health and Safety Risks
I. Executive Order 13211: Actions Concerning Regulations That
Significantly Affect Energy Supply, Distribution, or Use
J. National Technology Transfer and Advancement Act (NTTAA)
K. Congressional Review Act (CRA)

I. General Information

A. Executive Summary

The AIM Act was included as part of the Consolidated Appropriations
Act, 2021 that included funding for the Federal Government and the
Coronavirus Response and Relief Supplemental Appropriations, 2021.\1\
The AIM Act authorizes the EPA to regulate hydrofluorocarbons (HFCs) in
three main areas: phasing down the production and consumption of listed
HFCs; management of these HFCs and their substitutes; and facilitating
the transition to next-generation technologies by restricting use of
these HFCs in the sector or subsectors in which they are used. The AIM
Act is inherently inflationary because it phases down the production
and consumption of HFCs, which increases the consumer prices of goods
and services that rely upon or use HFCs for refrigeration or other
purposes. This final rule addresses where the AIM Act was forcing more
expensive technology onto consumers (through the Technology Transitions
provisions). This reconsideration ensures that the EPA meets our
statutory obligations under the AIM Act while ensuring that the Agency
keeps the cost of living as low as legally possible for all Americans.
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\1\ Public Law 116-260, div. S, Sec. 103, 134 Stat. 1182, 2255
(2020).
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1. Purpose of the Deregulatory Action
Subsection (i) of the AIM Act provides that the Administrator ``may
by rule restrict, fully, partially, or on a graduated schedule, the use
of a regulated substance \2\ in the sector or subsector in which the
regulated substance is used.'' \3\ The EPA may exercise this
discretionary authority either on its own initiative or in response to
petitions for a restriction on the use of one or more regulated
substance(s). In deciding whether and how to exercise this authority,
the EPA must consider the best available data, the availability of
substitutes (including technological achievability, commercial demand,
affordability for consumers, safety, and other relevant factors),
overall economic costs and environmental impacts as compared to
historical trends, and the remaining phasedown period for the regulated
substance(s), if applicable.\4\
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\2\ ``Regulated substance'' and ``HFC'' are used interchangeably
in this rule. The AIM Act defines ``regulated substance'' by
reference to a list of HFCs and the EPA has not attempted to add any
additional saturated hydrofluorocarbons to the statutory list
pursuant to subsection (c)(3). See 42 U.S.C. 7675(c)(1), (c)(2)(A).
\3\ See 42 U.S.C. 7675(i)(1).
\4\ See 42 U.S.C. 7675(i)(4)-(5).
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On October 24, 2023, the EPA published a final rule under
subsection (i) of the AIM Act entitled ``Phasedown of
Hydrofluorocarbons: Restrictions on the Use of Certain
Hydrofluorocarbons Under the American Innovation and Manufacturing Act
of 2020'' (2023 Final Rule).\5\ This final rule restricted the use of
HFCs in specific sectors or subsectors, established a process for
submitting technology transitions petitions, established recordkeeping
and reporting requirements, and addressed certain other elements
related to the effective implementation of the AIM Act. The 2023 Final
Rule became effective on December 26, 2023. The 2023 Final Rule applied
to over 40 subsectors across the aerosols, foams, and refrigeration,
air conditioning, and heat pumps sectors.
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\5\ See 88 FR 73098 (October 24, 2023).
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After publication of the 2023 Final Rule, manufacturers, importers,
and distributors of residential and light commercial air conditioning
and heat pump equipment informed the EPA that the compliance date for
the restriction on installation will result in substantial stranded
inventory in that subsector for residential new construction, including
both single-family and multi-family dwellings, where builders order
heating and cooling equipment well in advance of knowing the exact date
of installation. In response, the EPA issued an interim final rule
(IFR) \6\ to address the unique circumstances of that particular
subsector to prevent such equipment from being stranded.
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\6\ See 88 FR 88825 (December 26, 2023).
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The EPA also received four administrative petitions for
reconsideration and several requests to adjust certain provisions of
the 2023 Final Rule after its publication.
On January 31, 2025, the President issued Executive Order 14192
(Unleashing Prosperity through Deregulation).\7\ On March 12, 2025,
against this backdrop, the EPA announced plans for deregulatory actions
to, among other things, lower the cost of living for American
families.\8\ On that same day, and as part of the larger Agency plan,
the EPA announced plans to reconsider the regulations promulgated via
the 2023 Final Rule ``that forces companies to use certain technologies
that increased costs on food at grocery stores and semiconductor
manufacturing.'' \9\
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\7\ See 90 FR 9065 (February 6, 2025).
\8\ See EPA Launches Biggest Deregulatory Action in U.S.
History, March 12, 2025, in the docket for this action.
\9\ See Trump EPA Announces OOOO b/c Reconsideration of Biden-
Harris Rules Strangling American Energy Producers, March 12, 2025,
in the docket for this action.
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On October 3, 2025, the EPA published a notice of proposed
rulemaking entitled ``Phasedown of Hydrofluorocarbons: Reconsideration
of Certain Regulatory Requirements Promulgated Under the Technology
Transitions Provisions of the American Innovation and Manufacturing Act
of 2020'' (October 2025 Proposal) \10\ that proposed revisions for
restrictions applicable to: certain intermodal refrigerated transport
containers, certain

[[Page 31286]]

industrial process refrigeration and chillers for industrial process
refrigeration equipment used in semiconductor manufacturing, retail
food--supermarket systems, retail food--remote condensing units, cold
storage warehouses, residential and light commercial air conditioning
and heat pump systems, and certain laboratory equipment, among other
provisions.
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\10\ See 90 FR 47999 (October 3, 2025).
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2. Summary of the Major Provisions of This Regulatory Action
This final rule addresses significant issues raised in
administrative petitions and input received from regulated industry and
other interested parties with respect to regulatory provisions
promulgated in the Code of Federal Regulations (CFR) pursuant to the
AIM Act subsection (i). In particular, the EPA received four
administrative petitions \11\ to reconsider certain provisions of 40
CFR part 84, subpart B, entitled ``Restrictions on the Use of
Hydrofluorocarbons,'' that were finalized in the 2023 Final Rule. We
also received other requests to reassess compliance dates and/or other
provisions finalized in the 2023 Final Rule. Specifically, this final
rule:
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\11\ See administrative petitions for reconsideration in the
docket for this action.
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1. Amends the intermodal refrigerated transport provisions at 40
CFR 84.54(a)(6) and 84.54(c)(7) to: (a) adjust the lower bound
temperature exclusion threshold of -50 [deg]C to -35 [deg]C, and (b)
change the location where that temperature is measured.
2. Amends the compliance date for certain chillers used for
industrial process refrigeration (IPR) and certain IPR equipment used
to manufacture semiconductors from January 1, 2026, and January 1,
2028, as applicable, to January 1, 2030.
3. Amends the global warming potential (GWP) limit (hereafter
``limit'') for retail food remote condensing units at 40 CFR
84.54(c)(11) from 150 or 300, as applicable, to 1,400 until January 1,
2032, and either 150 or 300, depending on charge size or whether it is
part of the high temperature side of a cascade system, starting January
1, 2032.
4. Amends the limit for supermarket systems at 40 CFR 84.54(c)(12)
from 150 or 300, as applicable, to 1,400 until January 1, 2032, and
either 150 or 300, depending on charge size or whether it is part of
the high temperature side of a cascade system, starting January 1,
2032.
5. Amends 40 CFR 84.54(e)(2) to allow supermarket systems to
increase system cooling capacity up to 15 percent from zero percent
compared to original installed capacity without this being considered
the installation of a new system.
6. Amends the limit for cold storage warehouses at 40 CFR
84.54(c)(9) from 150 or 300, as applicable, to 700 until January 1,
2032, and either 150 or 300, depending on charge size or whether it is
part of the high temperature side of a cascade system, starting January
1, 2032.
7. Amends the compliance date for refrigerated laboratory
centrifuges and laboratory shakers from January 1, 2026, to January 1,
2028.
8. Removes the installation deadline for systems in the residential
and light commercial air conditioning and heat pumps (AC/HP) subsector,
where all specified components of such systems were domestically
manufactured or imported before January 1, 2025.
9. Corrects a typographical error at 40 CFR 84.58(b).
3. Impacts From This Rule
Table 1 of this preamble below provides a summary of both monetized
and non-monetized impacts. Monetized impacts include estimated
engineering cost savings for equipment owners in affected subsectors.
These cost savings arise from cases where additional flexibility
provided by the rule allows for the use of refrigerant-containing
equipment with lower capital and/or operating costs than equipment that
would otherwise likely be chosen without additional flexibility. As
part of fulfilling analytical guidance with respect to Executive Order
12866, the EPA presents estimates of the present value (PV) of the
benefits and costs over the full time series included in this analysis
(2026-2050). To calculate the PV of the cost savings of the rule,
annual savings are discounted to 2025 at three percent and seven
percent discount rates as directed by Office of Management and Budget
(OMB) Circular A-4. The EPA also presents the equivalent annualized
value (EAV), which represents a flow of constant annual values that,
had they occurred in each year in the time series, would yield a sum
equivalent to the PV, discounted at three percent and seven percent.

Table 1--Summary of Monetized and Non-Monetized Economic Impacts, 2026-2050
[Millions of 2024 dollars]
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----------------------------------------------------------------------------------------------------------------
Monetized Impacts
----------------------------------------------------------------------------------------------------------------
Engineering Cost Savings in Affected Subsectors. 3 Percent discount rate
7 Percent discount rate
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PV EAV PV EAV
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$976 $56 $653 $56
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Non-Monetized Impacts
----------------------------------------------------------------------------------------------------------------
Benefits and Cost Savings:
<bullet> Avoided loss of ability to produce semiconductor wafers within the United States...................
<bullet> National security benefits.........................................................................
Costs and Forgone Benefits:
<bullet> Indirect costs via HFC market impacts..............................................................
<bullet> Costs to equipment manufacturers and suppliers related to incremental investments required.........
<bullet> Forgone benefits from potential increased emissions of HFCs........................................
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The EPA anticipates that this action will result in indirect market
and/or distributional consumer effects not explicitly included in the
monetized impacts. For example, as supermarkets operate with extremely
thin margins (1-

[[Page 31287]]

2%), supermarkets are not able to internalize additional regulatory
costs much and externalize those costs on customers, thereby driving up
costs of food and other goods. Therefore, we expect that almost all, if
not all, of the cost savings for supermarkets will be passed onto
customers, thus reducing the burden of AIM Act implementation under
subsection (i) on consumers in the form of increased prices for food
and other goods.
There are economic effects with potentially significant
consequences related to other provisions as well, including for
semiconductor manufacturing. For example, under the baseline
requirements, semiconductor facilities using IPR or Chillers for IPR
equipment with charge sizes of 100 pounds or less faced technically
infeasible requirements. Such facilities would have been forced to
delay operations or invest in costly pre-commercial technologies. To
the extent productivity may have been impacted, the costs could have
been significantly larger than the costs of refrigeration
equipment.\12\
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\12\ Comment from Semiconductor Equipment and Materials
International (SEMI): ``The economic costs of downtime in
semiconductor production are extraordinary. A modern fabrication
plant can lose millions of dollars per day in halted output.'' See
Docket ID No. EPA-HQ-OAR-2025-0005-0051.
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In addition, this action may result in increased demand for HFCs.
This in turn may result in tighter supply \13\ and higher HFC prices
for downstream consumers, including users of HFCs in subsectors outside
the scope of this final rule. In combination with other AIM Act rules,
the adjustments in this action can continue to support an efficient
transition from HFCs to lower-GWP alternatives, consistent with the
statutory requirements under the AIM Act.
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\13\ Overall supply of HFCs is constrained by the statutory HFC
phasedown caps contained in subsection (e) of the AIM Act.
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For more detailed information, see the memorandum entitled Analysis
of Economic and Environmental Impacts--Phasedown of Hydrofluorocarbons:
Reconsideration of Certain Regulatory Requirements Promulgated Under
the Technology Transitions Provisions of the American Innovation and
Manufacturing Act of 2020 (``Economic and Environmental Impacts
Memo''). The information provided in the Economic and Environmental
Impacts Memo and in this section of the preamble is descriptive and for
informational purposes only; it is not part of the rationale for
reaching the decisions in this final rule. The EPA is not relying on
this section or the Economic and Environmental Impacts Memo as a record
basis for the final action.

B. Does this action apply to me?

You may be potentially affected by this rule if you manufacture,
import, export, sell, distribute, install, or use refrigerated
transport intermodal containers, chillers and industrial process
refrigeration equipment used in the manufacture of semiconductors,
retail food refrigeration equipment for remote condensing units and
supermarkets, refrigeration systems in cold storage warehouses,
refrigerated centrifuges, refrigerated laboratory shakers, or
residential and light commercial air-conditioning and heat pump
systems. Potentially affected categories, by North American Industry
Classification System (NAICS) code, are:

<bullet> 236116; New Multifamily Housing Construction (except For-Sale
Builders)
<bullet> 236117; New Housing For-Sale Builders
<bullet> 236118; Residential Remodelers
<bullet> 236210; Industrial Building Construction
<bullet> 236220; Commercial and Institutional Building Construction
<bullet> 238220; Plumbing, Heating, and Air Conditioning Contractors
<bullet> 325120; Industrial Gas Manufacturing
<bullet> 333242; Semiconductor Machinery Manufacturing
<bullet> 333415; Air Conditioning and Warm Air Heating Equipment and
Commercial and Industrial Refrigeration Equipment Manufacturing
<bullet> 333998; All Other Miscellaneous General Purpose Machinery
Manufacturing
<bullet> 334413; Semiconductor and Related Device Manufacturing
<bullet> 335220; Major Household Appliance Manufacturing
<bullet> 423620; Household Appliances, Electric Housewares, and
Consumer Electronics Merchant Wholesalers
<bullet> 423720; Plumbing and Heating Equipment and Supplies
(Hydronics) Merchant Wholesalers
<bullet> 423730; Warm Air Heating and Air Conditioning Equipment and
Supplies Merchant Wholesalers
<bullet> 423740; Refrigeration Equipment and Supplies Merchant
Wholesalers
<bullet> 424410; General Line Grocery Merchant Wholesalers
<bullet> 424420; Packaged Frozen Food Merchant Wholesalers
<bullet> 445110; Supermarkets and Other Grocery (except Convenience)
Stores
<bullet> 445131; Convenience Retailers
<bullet> 449210; Electronics and Appliance Retailers
<bullet> 452311; Warehouse Clubs and Supercenters
<bullet> 483111; Deep Sea Freight Transportation
<bullet> 484230; Specialized Freight (Except Used Goods) Trucking,
Long-Distance
<bullet> 493120; Refrigerated Warehousing Storage
<bullet> 531110; Lessors of Residential Buildings and Dwellings
<bullet> 531120; Lessors of Nonresidential Buildings (except
Miniwarehouses)
<bullet> 541380; Testing Laboratories
<bullet> 561210; Facilities Support Services
<bullet> 811412; Appliance Repair and Maintenance

This list is not intended to be exhaustive but rather provides a
guide for readers regarding entities likely to be regulated by this
action. This list includes the types of entities that the EPA is now
aware could potentially be regulated by this action. Other types of
entities not listed could also be regulated. To determine whether your
entity may be regulated by this action, you should carefully examine
the applicability criteria found in the regulatory text at the end of
this document. 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.

II. Statutory Background and Regulatory History

A. What is the authority for this action?

The AIM Act authorizes the EPA to regulate HFCs in three main
areas: phasing down the production and consumption of listed HFCs;
management of these HFCs and their substitutes; and facilitating the
transition to next-generation technologies by restricting use of these
HFCs in the sector or subsectors in which they are used. This rule
focuses on the third area: the transition to next-generation
technologies.
Subsection (i) of the AIM Act, titled ``Technology Transitions,''
provides that ``the Administrator may by rule restrict, fully,
partially, or on a graduated schedule, the use of a regulated substance
in the sector or subsector in which the regulated substance is used.''
\14\ Unlike other provisions in the AIM Act, the Administrator's
subsection (i) authority is discretionary. When deciding whether and
how to exercise this discretionary authority, the EPA ``shall, to the
extent practicable, factor in'' several enumerated considerations,
including use of ``the best available data,'' ``the availability of
substitutes for

[[Page 31288]]

use of the regulated substance that is the subject of the rulemaking or
petition, as applicable, in a sector or subsector, taking into account
technological achievability, commercial demands, affordability for
residential and small business consumers, safety, consumer costs,
building codes, appliance efficiency standards, contractor training
costs, and other relevant factors, including the quantities of
regulated substances available from reclaiming, prior production, or
prior import,'' ``overall economic costs and environmental impacts, as
compared to historical trends,'' and ``the remaining phase-down period
for regulated substances'' under applicable regulations.\15\ In this
way, Congress expressly required the EPA to consider the cost of
subsection (i) rules, including costs to consumers, as well as
additional factors like technical feasibility, and authorized the
Agency to consider ``other relevant factors'' pertaining to the
availability of substitutes. For additional discussion of the EPA's
authorities under subsection (i) of the AIM Act, please refer to the
2023 Final Rule.\16\
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\14\ See 42 U.S.C. 7675(i)(1).
\15\ See 42 U.S.C. 7675(i)(4)(A)-(D); see also id. 7675(i)(5)
(``In carrying out this subsection, the Administrator shall--(A)
evaluate substitutes for regulated substances in a sector or
subsector, taking into account technological achievability,
commercial demands, safety, overall economic costs and environmental
impacts, and other relevant factors; and (B) make the evaluation
under subparagraph (A) available to the public, including the
factors associated with the safety of those substitutes.'').
\16\ See 88 FR 73098 (October 24, 2023).
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In addition, subsection (k)(1)(A) of the AIM Act authorizes the EPA
to promulgate such regulations as are necessary to carry out the AIM
Act's functions, including its obligations to ensure that requirements
of the AIM Act are satisfied.\17\ Subsection (k)(1)(C) of the AIM Act
further provides that CAA sections 113, 114, 304, and 307 apply to the
AIM Act and any regulations promulgated thereunder as though the AIM
Act were part of title VI of the CAA.\18\ Accordingly, this rulemaking
is subject to the procedural requirements of CAA section 307(d).\19\
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\17\ See 42 U.S.C. 7675(k)(1)(A).
\18\ See 42 U.S.C. 7675(k)(1)(C).
\19\ See 42 U.S.C. 7607(d)(1)(I).
---------------------------------------------------------------------------

The EPA noted in the preamble to the proposed rule that this
rulemaking does not merit the use of negotiated rulemaking procedures
described in paragraph (i)(2). The EPA received no comments on this
issue and is not revisiting it in this final rule.
Unless provided otherwise by statute, an agency may revise or
rescind prior actions so long as it acknowledges the change in
position, provides a reasonable explanation for the new position, and
considers legitimate reliance interests in the prior position.\20\
Relevant case law confirms that legitimate reliance interests do not
create a higher bar for adopting a new policy but rather serve as
relevant considerations along with other relevant factors informing the
new policy.\21\
---------------------------------------------------------------------------

\20\ See FDA v. Wages & White Lion Invs., LLC, 145 S. Ct. 898
(2025); FCC v. Fox TV Stations, Inc., 556 U.S. 502 (2009); Motor
Vehicle Mfrs. Ass'n v. State Farm Mut. Auto. Ins. Co., 463 U.S. 29
(1983); Clean Air Council v. Pruitt, 862 F.3d 1, 8 (D.C. Cir. 2017)
(``Agencies obviously have broad discretion to reconsider a
regulation at any time.'').
\21\ DHS v. Regents of Univ. of Cal., 591 U.S. 1, 21 (2020)
(``Agencies are not compelled to explore every alternative device
and thought conceivable by the mind of man. But, because DHS was not
writing on a blank slate, it was required to assess whether there
were reliance interests, determine whether they were significant,
and weigh any such interests against competing policy concerns.'')
(internal citations omitted); MediNatura, Inc. v. FDA, 998 F.3d 931,
942-43 (D.C. Cir. 2021) (in withdrawing a 30-year old guidance
document on enforcement of homeopathic drugs, FDA considered
reliance interests and reasonably explained that the new policy was
supported by safety concerns, the continued expansion in the
impacted industry, and the agency's general interest in its risk-
based enforcement approach).
---------------------------------------------------------------------------

The EPA has considered the reliance interests presented to the
Agency in this rulemaking in the comments and elsewhere. Here, the
Agency has considered the reliance interests detailed in the comments
along with other considerations, including the AIM Act's subsection
(i)(4) statutory factors, and has determined that the requirements
should be amended as is detailed in this rulemaking. The EPA received
specific comments on reliance interests relating to the retail food--
supermarkets, retail food--remote condensing units, and cold storage
warehouses subsectors. For particular responses to those comments, see
section IV.K.2 of this preamble.

B. Severability

This final rule addresses restrictions in several distinct
refrigeration and air conditioning applications regulated under
subsection (i) of the AIM Act. The EPA has independently considered
each of those provisions in this rule, and intends that each change to
restrictions in distinct applications be severable from all other
changes to restrictions in distinct applications. The changes made for
each application are supported by their own record and analyses,
including separate analysis of the AIM Act statutory factors under
subsection (i)(4). If a court were to review the EPA's final action and
invalidate any particular change to a restriction, the Agency would
intend that any remaining changes remain effective. This final rule
also includes an interpretation of the requirements contained in
subsection (i)(6) of the AIM Act. If a court were to review the EPA's
final action and invalidate the Agency's interpretation of subsection
(i)(6), the EPA would intend that the substantive amendments to
applicable restrictions remain with an effective date reflecting the
outcome of judicial review.

C. Summary of 2023 Final Rule

In the 2023 Final Rule, the EPA considered a number of petitions
submitted under subsection (i)(3) to restrict, fully, partially, or on
a graduated schedule, the use of HFCs in the sector or subsector in
which the regulated substance is used.\22\ The Agency's analysis
supporting that final rule endeavored to apply the factors in
subsection (i)(4) of the AIM Act to the information available to the
EPA at that time, including with respect to availability of
substitutes, overall economic costs and environmental impacts, and the
remaining phasedown period for HFCs. Among other things, the 2023 Final
Rule prohibited the domestic manufacture and import of aerosols, foams,
and factory-completed refrigeration, AC, and heat pump products as well
as the installation of refrigeration, AC, and heat pump systems that
use HFCs or HFC blends above specified limits.
---------------------------------------------------------------------------

\22\ See 88 FR 73098 (October 24, 2023).
---------------------------------------------------------------------------

The compliance dates for these restrictions varied by sector and
subsector and generally ranged from January 1, 2025, to January 1,
2028. The rule also prohibited the sale, distribution, and export of
factory-completed products that do not comply with the relevant
restrictions three years after the prohibition on domestic manufacture
and import goes into effect. The rule did not prohibit the sale,
distribution, and export of components needed to repair existing
refrigeration and air conditioning systems.
To meet the compliance dates and limits for the sectors and
subsectors with restrictions in the 2023 Final Rule, various degrees of
change were required. The Agency based decisions for compliance dates
and limits on a variety of factors, including, but not limited to:
petitions submitted under AIM Act subsection (i), comments received on
those petitions, information we provided in market characterization
technical support documents located in the docket for the 2023 Final
Rule, and comments on the proposal to the 2023 Final Rule. For example,
for sectors such as aerosols and foams, alternatives

[[Page 31289]]

below the limits were in use, often to large degrees. Similarly,
several subsectors in the refrigeration and AC sector, such as motor
vehicle air conditioning, household refrigerators and freezers, retail
food--refrigeration stand-alone units, and others, had alternatives
below the applicable limits that were widely available and in use.
Other subsectors had known alternatives with more nascent technologies
such as retail food--supermarket systems. The subsectors with
identified alternatives with more limited use generally had later
compliance dates, such as Chiller for IPR systems and IPR systems that
operate at temperatures between -50 [deg]C to -30 [deg]C. Equipment in
such subsectors had compliance dates of January 1, 2028. See the 2023
Final Rule and the Regulatory Impact Analysis and other documents in
that docket for additional information.

D. Summary of 2023 Interim Final Rule

After publication of the 2023 Final Rule, manufacturers, importers,
and distributors of residential and light commercial AC/HP equipment
informed the EPA that the compliance date for the restriction on
installation will result in substantial stranded inventory in that
subsector for residential new construction, including both single-
family and multi-family dwellings, where builders order heating and
cooling equipment well in advance of knowing the exact date of
installation. In response, the EPA issued an IFR \23\ to address the
unique circumstances of that particular subsector to prevent such
equipment from being stranded. In particular, that rule extended the
installation compliance date from January 1, 2025, to January 1, 2026,
so long as all the components were manufactured in the United States or
imported into the United States before January 1, 2025.
---------------------------------------------------------------------------

\23\ See 88 FR 88825 (December 26, 2023).
---------------------------------------------------------------------------

E. Summary of Administrative Petitions and Requests Related to This
Rulemaking

The EPA received four administrative petitions to reconsider
certain aspects of the 2023 Final Rule.\24\ One petitioner requested
that the EPA adjust the temperature threshold and temperature location
for transport refrigeration--intermodal containers. Another requested
an extension of the compliance date for process refrigeration equipment
used in semiconductor manufacturing. Two separate petitioners requested
that the EPA consider limiting import, domestic manufacture, and
installation of condensing units used for residential and light
commercial AC/HP systems. The EPA granted reconsideration of these
administrative petitions in June 2024 \25\ and the October 2025
Proposal for this rulemaking provided an opportunity for public comment
on a set of proposed changes based on these administrative petitions.
The EPA also received other requests to adjust certain restrictions at
40 CFR part 84, subpart B for certain retail food subsectors,\26\ cold
storage warehouses,\27\ refrigerated laboratory centrifuges,\28\ and
laboratory shakers.\29\ In response to these requests and additional
concerns identified by the Agency and stakeholders, the EPA announced a
reconsideration of aspects of the 2023 Final Rule on March 12, 2025, as
one of the deregulatory actions included in the Administrator's
``Powering the Great American Comeback'' initiative.\30\
---------------------------------------------------------------------------

\24\ Three petitions for judicial review of the 2023 Final Rule
were also filed in the U.S. Court of Appeals for the D.C. Circuit
and are being held in abeyance. See Semiconductor Equipment &
Materials Int'l v. EPA (D.C. Cir. Case No. 23-1344); Chemours Co.
FC, LLC v. EPA (D.C. Cir. Case No. 23-1345); and Food Marketplace,
Inc. et al. v. EPA (D.C. Cir. Case No. 23-1347).
\25\ The four administrative petitions for reconsideration and
the EPA's responses granting reconsideration are in the docket for
this action.
\26\ See letter from trade association dated February 11, 2025,
in the docket for this action.
\27\ See request from trade association dated March 6, 2025, in
the docket for this action.
\28\ See request from manufacturer dated June 6, 2024, in the
docket for this action.
\29\ See request from manufacturer, dated April 8, 2025, in the
docket for this action.
\30\ See EPA Launches Biggest Deregulatory Action in U.S.
History, March 12, 2025, in the docket for this action.
---------------------------------------------------------------------------

F. Judicial Review and Administrative Review

The AIM Act regulations promulgated herein may be challenged in the
United States Court of Appeals for the District of Columbia Circuit.
Pursuant to CAA section 307(b)(1), petitions for judicial review of the
AIM Act regulations must be filed in that court within 60 days after
the date notice of this final action is published in the Federal
Register.
The AIM Act provides that certain sections of the CAA ``shall
apply'' to the AIM Act and actions ``promulgated by the Administrator
of [EPA] pursuant to [the AIM Act] as though [the AIM Act] were
expressly included in title VI of [the CAA].'' \31\ Among the
applicable sections of the CAA is section 307, which includes
provisions on judicial review. CAA section 307(b)(1) provides, in part,
that petitions for review must only be filed in the United States Court
of Appeals for the District of Columbia Circuit: (i) when the agency
action consists of ``nationally applicable regulations promulgated, or
final actions taken, by the Administrator,'' or (ii) when such action
is locally or regionally applicable, but ``such action is based on a
determination of nationwide scope or effect.'' \32\
---------------------------------------------------------------------------

\31\ See 42 U.S.C. 7675(k)(1)(C).
\32\ See 42 U.S.C. 7607(b)(1).
---------------------------------------------------------------------------

The AIM Act regulations promulgated herein are ``nationally
applicable regulations'' within the meaning of CAA section 307(b)(1).
These regulations establish regulatory requirements applicable across
the entire United States to implement restrictions under subsection (i)
of the AIM Act. The regulations promulgated herein amend an existing
nationally applicable regulation by adjusting a compliance deadline for
certain systems. The deadlines in the amended regulation and the
conditions required to qualify for those extended deadlines are
nationally applicable to all affected entities. Accordingly, under CAA
section 307(b)(1), petitions for judicial review of these AIM Act
regulations must be filed in the United States Court of Appeals for the
District of Columbia Circuit by July 27, 2026.
CAA section 307(d)(7)(B) further provides that ``[o]nly an
objection to a rule or procedure which was raised with reasonable
specificity during the period for public comment (including any public
hearing) may be raised during judicial review.'' This section also
provides a mechanism for the EPA to convene a proceeding for
reconsideration ``[i]f the person raising an objection can demonstrate
to the EPA that it was impracticable to raise such objection within
[the period for public comment] or if the grounds for such objection
arose after the period for public comment, (but within the time
specified for judicial review) and if such objection is of central
relevance to the outcome of the rule.'' \33\ Any person seeking to make
such a demonstration to us should submit a Petition for Reconsideration
to the Office of the Administrator, U.S. Environmental Protection
Agency, Room 3000, WJC South Building, 1200 Pennsylvania Ave. NW,
Washington, DC 20460, with a copy to both the person(s) listed in the
preceding FOR FURTHER INFORMATION CONTACT section and the Associate
General Counsel for the Air and Radiation Law Office, Office of General
Counsel (Mail Code 2344A), U.S. EPA, 1200 Pennsylvania Ave. NW,
Washington, DC 20460.
---------------------------------------------------------------------------

\33\ See 42 U.S.C. 7607(d)(7)(B).

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[[Page 31290]]

III. Summary of Final Action

A. Refrigerated Transport--Intermodal Containers

The EPA is finalizing amendments to provisions related to
refrigerated transport--intermodal containers, as proposed.
Specifically, this final rule raises the lower-bound temperature
exclusion threshold of -50 [deg]C to -35 [deg]C and changes the
location where that temperature is measured to the inside of the
container, referred to as the box temperature.
1. Background
Refrigerated transport--intermodal containers are refrigerated
containers with an integrated power source that allow uninterrupted
storage during transport on different mobile platforms, including
railways, road trucks, and vessels.\34\ These intermodal containers
used for refrigerated transport are regulated as products and systems
at 40 CFR 84.54(a)(6) and (c)(7), respectively, depending on their
design. They primarily carry perishable goods (e.g., food) and
pharmaceuticals at temperatures between -30 [deg]C and 16 [deg]C and
can be designed to operate at higher and lower temperatures.
---------------------------------------------------------------------------

\34\ See 88 FR 73171 (October 24, 2023).
---------------------------------------------------------------------------

The 2023 Final Rule restricted the use of HFCs in intermodal
containers when the temperature of the refrigerant entering the
evaporator (for direct heat exchange systems) or the temperature of the
fluid exiting (for chillers) is -50 [deg]C or higher.\35\ These
regulations do not apply where temperatures are below -50 [deg]C. At
the time, the EPA understood that several substitutes were available
for refrigerated transport--intermodal containers, including R-744
(also known as carbon dioxide or CO<INF>2</INF>),\36\ R-450A, R-
513A.\37\ As discussed in the October 2025 proposal, the EPA received
comments on the proposal to the 2023 Final Rule, including a request
for a higher limit than 700 for such equipment operating below -50
[deg]C.\38\ The EPA did not receive information at the time indicating
that operating such equipment with refrigerants below a 700 limit at
temperatures above -50 [deg]C and below -35 [deg]C was infeasible.
---------------------------------------------------------------------------

\35\ The restrictions for refrigerated transport--intermodal
containers began January 1, 2025. The EPA issued a no action
assurance on January 17, 2025, regarding the restrictions at 40 CFR
84.54(a)(6) and (c)(7), which remained in effect until January 1,
2026. The EPA extended the no action assurance on December 22, 2025,
until September 1, 2026, or the date this rulemaking is finalized,
whichever occurs earlier.
\36\ R-744 is the ASHRAE refrigerant designation for carbon
dioxide (CO<INF>2</INF>).
\37\ See 88 FR 73172 (October 24, 2023).
\38\ See 90 FR 48002 (October 3, 2025).
---------------------------------------------------------------------------

After publication of the 2023 Final Rule, a manufacturer of
intermodal containers that maintain a range of temperatures, petitioned
the EPA to raise the temperature threshold and change the temperature
measurement location for this subsector.\39\ The petitioner requested
the regulatory text at 40 CFR 84.54(a)(6) and (c)(7) be changed to,
``Effective January 1, 2025, refrigerated transport--intermodal
containers designed to reach and maintain -35 [deg]C box temperature or
higher using a regulated substance, or a blend containing a regulated
substance, with a global warming potential of 700 or greater.'' In
particular, the petitioner requested that the EPA adjust the
temperature threshold to distinguish between refrigerants used for deep
frozen cargo and those used for fresh and frozen cargo. The petitioner
noted that deep frozen cargo containers are used to transport cargo
that require temperatures at or below -35 [deg]C and include critical
life sciences products such as blood plasma and pharmaceuticals. The
petitioner stated that intermodal containers used to transport deep
frozen cargo must use refrigerants with lower boiling points, including
R-404A and R-452A.\40\ This contrasts with fresh and frozen cargo
containers, which the petitioner noted require temperatures that range
from -30 [deg]C to 30 [deg]C, and previously could use R-134a. One
compliant refrigerant that can achieve temperatures in this range, and
is currently used, includes R-513A.\41\ The petitioner indicated that
there are no available refrigerants below the applicable limit that can
achieve and maintain box temperatures below -35 [deg]C.
---------------------------------------------------------------------------

\39\ See manufacturer's administrative petition for
reconsideration in the docket for this action.
\40\ See email from manufacturer, dated January 16, 2025, in the
docket for this action.
\41\ See materials from manufacturer submitted November 2023 in
the docket for this action.
---------------------------------------------------------------------------

In the administrative petition, the petitioner also requested an
adjustment to the location at which the temperature is measured from
the ``temperature of the refrigerant entering the evaporator (for
direct heat exchange systems) or the temperature of the fluid exiting
(for chillers)'' to the ``box temperature'' because this measurement is
more commonly used by the industry in this subsector. The box
temperature is the temperature within the intermodal refrigerated
transport container (i.e., the ``box''). The petitioner also requested
that the EPA clarify that the temperature measurement be based on the
lowest temperature at which the equipment is ``designed to reach and
maintain.'' The petitioner further explained that this subsector uses
direct expansion equipment, not chillers, so the reference to chillers
in the regulatory text is unnecessary.
Based on the new information from the administrative petition, the
EPA agreed with the petitioner that there are currently no refrigerants
available with sufficiently low boiling points and high refrigeration
capacities for this temperature range. The EPA thus proposed to raise
the temperature threshold for this equipment from -50 [deg]C to -35
[deg]C. The EPA also agreed with the petitioner that the location at
which the temperature is measured is better suited as the box
temperature. The EPA thus also proposed to adjust the location at which
the temperature is measured to be the box temperature.\42\
---------------------------------------------------------------------------

\42\ See 90 FR 47999 (October 3, 2025).
---------------------------------------------------------------------------

2. Final Rule
The EPA is amending the provisions related to refrigerated
transport--intermodal containers as proposed. The EPA evaluated the
additional information provided by the petitioner \43\ after
publication of the 2023 Final Rule, the comments provided on the
proposed rule, and other information, and reassessed the factors under
AIM Act subsection (i)(4). The Agency concludes that refrigerants used
to reach and maintain such low temperatures in intermodal containers
require refrigerants with sufficiently low boiling points and high
refrigeration capacities.\44\ Among other rationale provided within
this section, section IV.A of this preamble, and in the Response to
Comments document, the Agency finds that there is no alternative that
is currently available that meets the limit established in the 2023
Final Rule and which could meet the needs of intermodal refrigerated
transport equipment designed to operate at box temperatures below -35
[deg]C. Given the transportation conditions necessary for shipping
blood plasma, pharmaceuticals, temperature-sensitive enzymes, dangerous
goods, and other materials at temperatures below -35 [deg]C, the EPA
concludes that targeted relief is appropriate and consistent with the
factors and considerations set out in AIM Act subsection (i)(4) given
the change in our understanding of availability of substitutes for this
temperature range for this equipment. The Agency describes and responds
to

[[Page 31291]]

comments in section IV.A of this preamble and the Response to Comments
document in the docket.
---------------------------------------------------------------------------

\43\ See materials from manufacturer submitted November 2023 in
the docket for this action.
\44\ See table of refrigerants (R-404A, R-452A, R-513A, R-450A,
R-744), their boiling points, and refrigeration capacities in the
docket for this action.
---------------------------------------------------------------------------

B. Industrial Process Refrigeration and Chillers for Industrial Process
Refrigeration in Semiconductor Manufacturing

The EPA is finalizing amendments to provisions related to IPR and
Chillers for IPR used to manufacture semiconductors as proposed.
Specifically, the EPA is extending the compliance date for certain IPR
and Chillers for IPR. The compliance date is extended from January 1,
2026, and January 1, 2028, as applicable, to January 1, 2030. This
extension is limited to equipment used in semiconductor manufacturing
that has a charge size of 100 pounds or less.
1. Background
The EPA considers refrigeration equipment used in semiconductor
manufacturing to fall within the IPR and Chillers for IPR
subsectors.\45\ The refrigeration equipment is often built into
specialized machines that sort, mark, and cut wafers during the
semiconductor manufacturing process, referred to as ``Semiconductor
Manufacturing and Related Equipment,'' or SMRE, throughout this rule.
SMRE may operate at a range of temperatures depending on the function
being performed and typically must maintain precise temperatures to
produce high-quality semiconductor wafers.
---------------------------------------------------------------------------

\45\ See 88 FR 73119 (October 24, 2023).
---------------------------------------------------------------------------

IPR systems are used to cool process streams at a specific point in
manufacturing and other industrial processes (e.g., in the chemical,
pharmaceutical, and petrochemical industries). IPR systems are directly
linked to the industrial process, meaning the refrigerant leaving the
condenser and metering device is delivered directly to the heat source
before returning to the compressor.\46\
---------------------------------------------------------------------------

\46\ See 88 FR 73141-42.
---------------------------------------------------------------------------

A chiller is a type of equipment that uses refrigerant to cool
water or a brine solution that is then pumped to fan coil units or
other air handlers to cool the air that is supplied to the conditioned
spaces. The heat absorbed by the water or brine can be used for heating
purposes and/or transferred directly to the air (``air-cooled''), to a
cooling tower or body of water (``water-cooled''), or through
evaporative coolers (``evaporative-cooled'').\47\ Chillers can be used
to cool process streams in industrial applications; in such instances,
these chillers are regulated as ``Chillers for IPR'' and not as
``IPR.'' Throughout this rule, the term ``IPR'' refers to IPR equipment
that does not use chillers. The term ``Chillers for IPR'' refers to IPR
equipment that utilizes chillers.
---------------------------------------------------------------------------

\47\ See 88 FR 73174.
---------------------------------------------------------------------------

Restrictions on the use of HFCs and HFC blends in IPR and Chillers
for IPR, including process equipment used to manufacture
semiconductors, are implemented at different limits (150, 300, and
700). The restrictions put in place by the 2023 Final Rule start on
either January 1, 2026, or January 1, 2028, depending on charge size
and the temperature at which the equipment is designed to operate.\48\
IPR and Chillers used for IPR at temperatures below -50 [deg]C are not
subject to restrictions under the 2023 Final Rule.
---------------------------------------------------------------------------

\48\ The EPA issued a no action assurance on December 22, 2025,
for this equipment that lasts until September 1, 2026, or until this
rule is finalized, whichever comes sooner.
---------------------------------------------------------------------------

A trade association representing the semiconductor industry
petitioned the EPA on December 22, 2023, to reconsider the compliance
dates that affect SMRE for the IPR and Chillers for IPR subsectors. The
petitioner submitted multiple supplemental letters to the Agency in the
following months clarifying requests in their administrative petition.
In one letter, they clarified that the administrative petition seeks
relief only for SMRE that have a charge size of 100 pounds or less.
They also clarified that for the relevant restrictions with compliance
dates of January 1, 2026, or January 1, 2028, they request delaying the
compliance date to January 1, 2030.\49\ Five SMRE suppliers also
submitted letters to the Agency between May 2024 and August 2024
indicating their support of the trade association's request to extend
the relevant compliance dates to January 1, 2030.\50\
---------------------------------------------------------------------------

\49\ See semiconductor trade association's letter to the EPA,
dated May 3, 2024, in the docket for this action.
\50\ See letters of support from five semiconductor equipment
manufacturing suppliers in the docket for this action.
---------------------------------------------------------------------------

The petitioner stated that equipment using substitute refrigerants
that fit this industry's unique circumstances will not be available by
the current compliance dates and estimated that developing and
implementing alternatives that are fit for purpose could take five
years.\51\ In particular, the petitioner noted that to manufacture
semiconductors, process refrigeration equipment must be able to
maintain precise control of narrow temperature tolerances, which can be
as small as 0.1 [deg]C <plus-minus> 0.05 [deg]C for some applications.
The petitioner also explained that using certain substitutes such as
CO<INF>2</INF> or lower flammability and flammable alternatives as a
refrigerant in SMRE would require changing how equipment is integrated
into semiconductor manufacturing facilities or limit the capabilities
of the process equipment.
---------------------------------------------------------------------------

\51\ See semiconductor trade association's supplemental
submission to the EPA, dated June 18, 2024, in the docket for this
action.
---------------------------------------------------------------------------

The petitioner stated that CO<INF>2</INF> offers a potential path,
yet some challenges would require further validation and testing.\52\
The petitioner has indicated that although R-728 \53\ may also be a
viable refrigerant, it would not be tested and validated in time to
meet the compliance dates established in the 2023 Final Rule.\54\ The
petitioner also indicated that R-32 and R-454C are not immediately
viable solutions because they both are flammable and R-32 would not
meet the limit for all SMRE use cases.
---------------------------------------------------------------------------

\52\ See semiconductor trade association's supplemental
submission to the EPA, dated June 18, 2024, in the docket for this
action.
\53\ R-728 is the ASHRAE refrigerant designation for nitrogen
gas (N<INF>2</INF>).
\54\ See February 20, 2024, meeting between semiconductor trade
association and the EPA in the docket for this action.
---------------------------------------------------------------------------

The petitioner noted that SMRE are custom-engineered and that
equipment availability is limited to meet the precise temperature and
humidity control requirements, particularly in the range between -50
[deg]C and -30 [deg]C. Due to the combination of factors that present
unique circumstances for this industry, the petitioner asserted that
the development of substitutes for SMRE will take more time than for
IPR and Chillers for IPR used in other sectors.\55\ Further details are
found in the proposed rule for this action.
---------------------------------------------------------------------------

\55\ See semiconductor trade association's letter to the EPA,
dated May 3, 2024, in the docket for this action.
---------------------------------------------------------------------------

The EPA agreed with the petitioner on the time needed to design,
test, qualify, validate, and deploy substitutes for SMRE with charge
sizes of 100 pounds or less. The EPA also agreed that a compliance
deadline of January 1, 2030, for this equipment, as suggested by the
petitioner and five semiconductor equipment manufacturing suppliers, is
reasonable for available substitutes to be developed. The EPA therefore
proposed to extend the compliance date for IPR and Chillers for IPR
equipment used in semiconductor manufacturing which have a charge size
of 100 pounds or less from January 1, 2026, and January 1, 2028, as
applicable, to January 1, 2030.
2. Final Rule
The EPA is finalizing provisions related to IPR and Chillers for
IPR used to manufacture semiconductors as

[[Page 31292]]

proposed. Specifically, the EPA is delaying the compliance dates for
certain IPR and Chillers for IPR from January 1, 2026, and January 1,
2028, as applicable, to January 1, 2030. This extension is limited to
equipment used in semiconductor manufacturing that has a charge size of
100 pounds or less.
Given the additional information the Agency received since the 2023
Final Rule, the Agency has reassessed the factors under subsection AIM
Act subsection (i)(4). The EPA finds that the semiconductor
manufacturing industry faces unique circumstances in manufacturing
semiconductors, including ensuring that available substitutes can
satisfy precise temperature control requirements. For example, the
petitioner explained that precise control is required to realize
process performance, including a uniform application of photoresist
coatings. They noted that small changes in temperature during
production can impact semiconductor device features, product
functionality, and product yields. As a further example, the petitioner
described how a 1 [deg]C change in temperature in a projection lens can
result in a few microns accuracy loss and would be ``catastrophic''
\56\ for semiconductor production. The EPA reviewed the comments and
information provided by industry, including letters submitted by five
semiconductor manufacturing equipment suppliers,\57\ that provided
additional details on the time needed to test and validate
alternatives. The EPA agrees with semiconductor manufacturers'
concerns, particularly for potential downtime and that such downtime
could have impacts on critical industries and national security. An
inability to acquire compliant technology could disrupt semiconductor
manufacturing output, which could lead to supply chain disruptions,
with global repercussions in the form of shortages and price
volatility. These supply chain disruptions could cascade across
industries dependent on advanced semiconductor chips, including defense
manufacturing, telecommunications, energy production, artificial
intelligence, and the automotive industry.
---------------------------------------------------------------------------

\56\ See 90 FR 48004 (October 3, 2025).
\57\ See letters of support from five semiconductor equipment
manufacturing suppliers in the docket for this action.
---------------------------------------------------------------------------

Given the information provided by the petitioner on the need for
more time to test, qualify, and validate substitutes, additional
related information from five semiconductor manufacturing equipment
suppliers, and comments on the proposed rule, the EPA agrees that a
transition to available substitutes will be able to be made by January
1, 2030. The EPA also finds that semiconductor manufacturing equipment
faced technically infeasible requirements to transition and that
companies that run facilities with such equipment would have been
forced to delay operations or invest in costly pre-commercial
technologies. To the extent that productivity may have been impacted,
the costs could have been significantly larger than the costs of
refrigeration. The Agency concludes that the targeted relief provided
for this equipment is appropriate given our change in understanding of
the availability of substitutes and the overall economic costs and
environmental impacts. The Agency describes and responds to comments in
section IV.B of this preamble and the Response to Comments document in
the docket.

C. Retail Food--Supermarket Systems

The EPA is finalizing, as proposed, amendments to the limits for
supermarket systems to establish a graduated schedule with an interim
limit of 1,400 starting January 1, 2027, and 150 or 300, depending on
charge size or whether it is part of the high temperature side of a
cascade system, starting January 1, 2032. The EPA is also finalizing a
provision allowing for a 15 percent increase in cooling capacity of an
existing supermarket system without triggering the requirements that
apply to new installations.
1. Background
Supermarket systems, also known as multiplex or centralized
systems, operate with racks of compressors installed in a machinery
room where different compressors turn on to match the refrigeration
load necessary to maintain temperatures in display cases in the sales
area. Direct supermarket designs circulate refrigerant from the
machinery room to the sales area, where it evaporates in display-case
heat exchangers, and then returns in vapor phase to the suction headers
of the compressor racks.\58\ Indirect supermarket designs include
secondary loop systems and cascade refrigeration systems. Indirect
systems use a chiller or other refrigeration system to cool a secondary
fluid that is then circulated throughout the store to the cases.
Compact chiller versions of an indirect system rely on a lineup of 10
to 20 units, each using small charge sizes. As the refrigeration load
changes, so does the number of active chillers. Each compact chiller is
an independent unit with its own refrigerant charge, reducing the
potential volume of refrigerant that could be released from leaks or
catastrophic failures. Despite the term ``chiller'' used in the
description, these systems are considered supermarket systems for
purposes of 40 CFR part 84, subpart B. Another type of supermarket
design, often referred to as a distributed refrigeration system, uses
an array of separate compressor racks located near the display cases
rather than having a central compressor rack system. Each of these
smaller racks handles a portion of the supermarket load,\59\ with 5 to
10 such systems in a store.\60\
---------------------------------------------------------------------------

\58\ Supermarket walk-in cold rooms are often integrated into
the system and cooled similarly, but a dedicated condensing unit can
be provided for a given storage room.
\59\ A supermarket may also use other types of refrigeration
equipment covered by separate subsectors, including stand-alone
units, remote condensing units, refrigerated beverage dispensers,
and ice machines. Such equipment is not a part of the ``supermarket
system'' subsector for purposes of 40 CFR part 84, subpart B merely
as a result of being located in a supermarket.
\60\ See 88 FR 73157-58 (October 24, 2023).
---------------------------------------------------------------------------

Supermarket systems account for a significant amount of HFC demand.
In particular, supermarket systems accounted for 24 percent of the
demand for HFCs in the refrigeration and AC/HP sector in 2025.\61\
Supermarket systems' large charge sizes and higher leak rates than many
other subsectors \62\ drive the demand for HFCs in these systems. Prior
to 2010, this subsector used R-22, which is an ozone-depleting
substance (ODS) that has been phased out, consistent with the
requirements of title VI of the CAA and its implementing regulations.
Since 2010, the majority of refrigeration systems in this subsector
have used refrigerants such as R-404A, R-407A, and R-507A. More
recently, supermarket systems have transitioned to substitutes such as
HFC/hydrofluoroolefin (HFO) blends, like R-448A, R-449A, and R-513A,
while a portion of the market has transitioned to CO<INF>2</INF>.
---------------------------------------------------------------------------

\61\ See EPA's Vintaging Model of ODS Substitutes Peer Review
Factsheet, in the docket for this action.
\62\ See Annex 3.9 of the 2024 U.S. Inventory of GHG Emissions
and Sinks, pg. 113, <a href="https://www.epa.gov/system/files/documents/2024-04/us-ghg-inventory-2024-annex-3-additional-source-or-sink-categories-part-a.pdf">https://www.epa.gov/system/files/documents/2024-04/us-ghg-inventory-2024-annex-3-additional-source-or-sink-categories-part-a.pdf</a>.
---------------------------------------------------------------------------

The 2023 Final Rule established restrictions on the installation of
HFCs and HFC blends in new supermarket systems starting January 1,
2027. The limit finalized in the 2023 Final Rule was 150 for systems
with refrigerant charge capacities greater than or equal to 200 pounds,
and 300 for systems with refrigerant charge capacities less than

[[Page 31293]]

200 pounds or for the high temperature side of cascade systems
irrespective of the total charge capacity. The EPA distinguished
between larger and smaller supermarket systems by their refrigerant
charge capacity based on a distinction between charge sizes in the
safety standards.\63\
---------------------------------------------------------------------------

\63\ The same distinction exists for systems in industrial
process refrigeration, cold storage warehouses, and retail food
remote condensing units. Elsewhere this notice refers to these
limits as ``150 or 300, as applicable'' with the meaning described
here. See 87 FR 76775-76 (December 15, 2022).
---------------------------------------------------------------------------

The 2023 Final Rule would have required new retail food supermarket
systems to be installed with refrigerants below a 150 or 300 limit, as
applicable, including CO<INF>2</INF>, certain HFOs, or certain HFC/HFO
blends.\64\ While some retailers had installed CO<INF>2</INF> in new
systems at the time, certain HFOs and HFC/HFO blends were still under
development and had not yet been listed by the SNAP program as
acceptable for use in new supermarket systems. While these additional
options were listed by SNAP in June 2024,\65\ and in advance of the
January 1, 2027, compliance date, the 2023 Final Rule would have
largely required retailers to install either CO<INF>2</INF> or newly
listed alternatives.
---------------------------------------------------------------------------

\64\ See 88 FR 73158-59 (October 24, 2023).
\65\ See 89 FR 50410 (June 13, 2024).
---------------------------------------------------------------------------

Certain food retailers and a trade association representing the
supermarket industry expressed concerns about the limited number and
types of substitutes that the EPA determined in the 2023 Final Rule
that would be available for use in supermarket systems by January 1,
2027. Specifically, they stated the rule restricts the food industry to
a handful of substitute refrigerants, including CO<INF>2</INF>,
ammonia,\66\ and those that are flammable,\67\ which they said are
impractical, infeasible, or create safety concerns.\68\
---------------------------------------------------------------------------

\66\ The ASHRAE designation for ammonia is R-717.
\67\ ANSI/ASHRAE Standard 34-2024 Designation and Safety
Classification of Refrigerants. This standard assigns a designation
consisting of two to three alphanumeric characters (e.g., A2L or
B1). The initial capital letter indicates the toxicity, and the
numeral and trailing letter, if any, denotes flammability. The
toxicity class is determined based on allowable exposure and is
signified with a capital letter, where ``A'' denotes lower toxicity
and ``B'' denotes refrigerants of higher toxicity. The standard also
assigns refrigerants a flammability classification of 1, 2, 2L, or 3
based upon the results of standardized testing for flame
propagation, heat of combustion, lower-flammability limit (LFL), and
burning velocity. The flammability classification ``1'' is given to
refrigerants that show no flame propagation. The flammability
classification ``2L'' is given to refrigerants that have lower
flammability. The flammability classification ``2'' is given to
refrigerants that are flammable. The flammability classification
``3'' is given to refrigerants that have higher flammability.
\68\ See trade association's letter to the EPA, dated February
11, 2025, in the docket for this action.
---------------------------------------------------------------------------

In addition, they asserted that CO<INF>2</INF> technologies are
unreasonably costly, and that, in their current state, they expend a
significant amount of energy to function at a cooling level comparable
to commonly used HFCs, that such technologies are unreliable, that
leaks are difficult to detect and repair, and that such leaks can be
catastrophic to the system's performance.\69\ These food retailers
shared that since water is used to cool CO<INF>2</INF> in such systems,
some states' water laws, like those in Nevada, would also be
prohibitive to the effective use of CO<INF>2</INF> systems.\70\ They
also asserted that CO<INF>2</INF> is not suitable for very large
stores, such as those that are 50,000 square feet or larger. They also
raised safety concerns about using ammonia, a regulated, toxic, and
flammable substance, in some retail environments.\71\ These food
retailers also said that refrigerants with flammability
classifications, such as A2L and A3 refrigerants, may not be
universally available due to delays in updates to local building codes
and potential shortages in technicians trained to use them.
Furthermore, these food retailers are concerned that future regulation
of per- and polyfluoroalkyl substances (PFAS) could require retailers
to change systems again from certain compliant fluorinated refrigerants
to others.\72\ Based on these concerns, food retailers requested
additional time to allow the technology and building codes to catch up.
They requested the EPA move the compliance deadline for supermarket
systems to the end of 2032 and suggested an interim limit of 1,400
starting January 1, 2027.\73\ In the proposal for this rulemaking, the
EPA requested comments on various topics including on costs associated
with transitioning to refrigerants in supermarkets systems below the
compliance limit of 150 or 300, as applicable, as well as costs
associated with meeting an interim compliance limit of 1,400.
---------------------------------------------------------------------------

\69\ Id.
\70\ See Memorandum--EPA Meetings Related to the Technology
Transitions Reconsideration Notice of Proposed Rulemaking, April 18,
2025, in the docket for this action.
\71\ See trade association's letter to the EPA, dated February
11, 2025, in the docket for this action.
\72\ CO<INF>2</INF>, hydrocarbons, and ammonia are not
fluorinated chemicals and are not PFAS. The EPA notes that the
Federal Government has not adopted a specific definition of PFAS and
has not included HFCs or HFOs in any PFAS-related restrictions.
\73\ See trade association's presentation dated April 18, 2025,
in the docket for this action.
---------------------------------------------------------------------------

The EPA proposed an interim limit of 1,400 starting January 1,
2027, for new supermarket systems. Starting January 1, 2032, the EPA
proposed the limit for supermarket systems to be 150 or 300, depending
on the characteristics of the system, as described previously in this
section.
A trade association representing the supermarket industry also
requested clarifications and potential changes to the codified
regulations at 40 CFR 84.54(e)(2) and (3) to ensure that certain
routine store refreshes, remodels, or layout changes do not trigger the
requirements for new systems.\74\ The 2023 Final Rule discussed two
scenarios in which the EPA would consider modifications to an existing
system to be equal to a new installation requiring the use of compliant
refrigerants:
---------------------------------------------------------------------------

\74\ See email from trade association, dated April 24, 2025, in
the docket for this action.
---------------------------------------------------------------------------

<bullet> When an existing system's cooling capacity is increased as
measured in British Thermal Units (BTU) per hour, and
<bullet> When replacing 75 percent or more of evaporators (by
number) and 100 percent of the compressor racks, condensers, and
connected evaporator loads of an existing system.
The trade association stated that it is normal for stores to
modestly expand the cooling capacity of existing systems when doing a
remodel to accommodate additional products and layouts. They gave a
specific example in which expanding a refrigerated case by 60 inches
could increase the overall cooling capacity of the system, meaning it
would be treated as a new system under the regulations at 40 CFR part
84 subpart B. The trade association requested that the EPA allow
supermarkets to increase the cooling capacity measured in BTU per hour
by up to 25 percent before the equipment is considered a new system.
The EPA requested comments on whether to allow supermarket systems to
expand cooling capacity by some amount without triggering the criteria
for installation of a new system, and if so, what that increase could
be (e.g., 25 percent).
The EPA requested comments on whether to allow supermarket systems
to increase cooling capacity to a certain degree without triggering a
new installation during routine store refreshes, remodels, or layout
changes. The EPA did not propose a specific increase in cooling
capacity that would be allowable without triggering a new installation
of a supermarket system.

[[Page 31294]]

2. Final Rule
The EPA is finalizing, as proposed, amendments to the limits for
supermarket systems to establish a graduated schedule with an interim
limit of 1,400 starting January 1, 2027, and 150 or 300, depending on
charge size or whether it is part of the high temperature side of a
cascade system, starting January 1, 2032. The EPA is also finalizing a
provision allowing for a 15 percent increase in cooling capacity of an
existing supermarket system without triggering the requirements that
apply to new installations.
a. Graduated Schedule
The EPA is finalizing a graduated schedule for the use of HFCs in
new supermarket systems as proposed. Specifically, the EPA is relaxing
the existing limit, on an interim basis, to 1,400 starting January 1,
2027, and a limit of 150 or 300 starting January 1, 2032. The limit of
150 is for supermarket systems with refrigerant charge capacities
greater than or equal to 200 pounds, and 300 for supermarket systems
with refrigerant charge capacities less than 200 pounds or for the high
temperature side of cascade systems irrespective of the total charge
capacity. The limits of 150 or 300, as described here, are the same
limits as those promulgated with the 2023 Final Rule, just on an
extended timeline. The EPA has reassessed the four factors under AIM
Act subsection (i)(4) given the additional information received ahead
of the October 2025 Proposal and during the comment period. The Agency
understands the need for additional flexibility for supermarket systems
in the near term, and acknowledges the complexity involved with
designing and installing such systems and potential challenges with
building code adoption, particularly at the local level. The interim
limit provides additional flexibility to retailers installing new
equipment in the near term. The EPA also notes that challenges in
deploying such systems vary across certain geographical areas of the
United States which can result in lagging adoption in certain areas.
The targeted relief in this rule is appropriate given changes in our
understanding of the availability of substitutes and the overall
economic costs and environmental impacts. The Agency describes and
responds to comments, including those related to building codes, energy
efficiency, and more, in section IV.C of this preamble and the Response
to Comments document in the docket.
The EPA also recognizes that some supermarkets already use
refrigerants that would have complied with the 2023 Final Rule's
limits. This final rule does not prevent manufacturers or installers
from choosing to use refrigerants below the limits of 150 or 300 ahead
of the new compliance requirements for new systems. The EPA anticipates
the additional time for compliance will allow these systems to continue
to be improved and have additional widespread availability across the
country. Supermarket systems are not off-the-shelf systems and are
configured with many different components to meet the specific needs of
store in which it will be used. The graduated schedule considers this
as some retailers may transition to these available substitutes sooner
than January 1, 2032, while others may require additional flexibility.
b. Expansion of Existing Supermarket Systems
In this final rule, the EPA is establishing that an increase in
cooling capacity of a supermarket system measured in BTU per hour of up
to 15 percent would not be considered a new installation. The EPA is
aware that supermarkets often undergo routine store refreshes,
remodels, or layout changes which may occur once or twice over the
lifetime of the supermarket system to update the look of the retail
floor or improve overall efficiency. The proposed rule discussed the
EPA's intention, consistent with past practice from the phaseout of R-
22, where the Agency considered if there was sufficient cooling
capacity within the system to support the expansion (e.g. new display
cases), then the store is not changing the intended purpose of the
system, and may use virgin R-22 after the modification/remodel. If the
expansion includes an increase in cooling capacity, then the EPA
presumes that the system's purpose is changing and a new system is
being manufactured. In other words, changes that expanded cooling
capacity for R-22 supermarket systems beyond the initial system designs
were treated as new systems. In this rule the EPA is acknowledging that
for the purposes of subsection (i) of the AIM Act, minor changes during
store refreshes, remodels, or layout changes do not trigger treatment
as a new system and has set an upper bound as discussed in section
IV.C.2 of this preamble.

D. Retail Food--Remote Condensing Unit Systems

The EPA is finalizing amendments to the limits for retail food
remote condensing units to establish an interim limit of 1,400 upon the
effective date of this rule, and 150 or 300, depending on charge size
or whether it is part of the high temperature side of a cascade system,
starting January 1, 2032.
1. Background
Remote condensing units are a type of retail food refrigeration
equipment with refrigeration capacities typically ranging from 1 kW to
20 kW (0.3 to 5.7 refrigeration tons). They are composed of one (and
sometimes two) compressor(s), one condenser, and one receiver assembled
into a single unit, normally located external to the sales area. This
equipment is connected to one or more nearby evaporator(s) used to cool
food and beverages stored in display cases and/or walk-in storage
rooms. A cascade system might be used, for example, to reach low
temperatures in a long-term storage room. A supermarket often uses
remote condensing units in food retail environments such as dairy and
deli displays. Remote condensing units are also commonly installed in
convenience stores and specialty shops, such as bakeries and butcher
shops.\75\
---------------------------------------------------------------------------

\75\ See 88 FR 73157 (October 24, 2023).
---------------------------------------------------------------------------

The 2023 Final Rule established restrictions on the use of HFCs in
new remote condensing unit systems installed starting January 1, 2026.
The limit was 150 for systems with refrigerant charge capacities
greater than or equal to 200 pounds, and 300 for systems with
refrigerant charge capacities less than 200 pounds or for the high
temperature side of cascade systems irrespective of the total charge
capacity. The EPA distinguished between larger and smaller remote
condensing units by their refrigerant charge capacity based on a
distinction between charge sizes in the safety standards.\76\
---------------------------------------------------------------------------

\76\ See 87 FR 76775-76 (December 15, 2022).
---------------------------------------------------------------------------

The 2023 Final Rule would have required new retail food remote
condensing unit systems to be installed with refrigerants below a 150
or 300 limit, as applicable, including CO<INF>2</INF>, certain HFOs, or
certain HFC/HFO blends.\77\ In general, retail food remote condensing
units have lower relative charge sizes compared to supermarket systems,
often under 200 pounds, meaning they can generally use refrigerants
complying with the 300 limit. While some retailers had installed
CO<INF>2</INF> in new systems at the time, other alternatives including
certain HFOs and HFC/HFO blends were still under development and had
not yet been listed by the SNAP program as acceptable for use in new
remote

[[Page 31295]]

condensing units. While these additional options were listed by SNAP in
June 2024,\78\ and in advance of the January 1, 2026, compliance date,
the 2023 Final Rule would have largely made these relatively new HFC/
HFO blends as the primary options for new installations of remote
condensing units.
---------------------------------------------------------------------------

\77\ See 88 FR 73157 (October 24, 2023).
\78\ See 89 FR 50410 (June 13, 2024).
---------------------------------------------------------------------------

Certain supermarket retailers and a trade association expressed
concerns about the limited number and types of substitutes that the EPA
determined in the 2023 Final Rule would be available for use in remote
condensing units by January 1, 2026. Specifically, they stated that the
rule restricts the food industry to a handful of substitute
refrigerants, including CO<INF>2</INF>, ammonia, and those that are
flammable,\79\ which they stated are either impractical, infeasible, or
create safety concerns.\80\
---------------------------------------------------------------------------

\79\ ANSI/ASHRAE Standard 34-2024 Designation and Safety
Classification of Refrigerants.
\80\ See trade association's letter to the EPA, dated February
11, 2025, in the docket for this action.
---------------------------------------------------------------------------

In addition they asserted that CO<INF>2</INF> technologies are
costly, and that, in their current state, they expend a significant
amount of energy to function at a cooling level comparable to commonly
used HFCs, that such technologies are unreliable, that leaks are
difficult to detect and repair, and that such leaks can be catastrophic
to the system's performance.\81\ These food retailers also said that
refrigerants with flammability characteristics, such as A2L and A3
refrigerants, may not be universally available due to delays in updates
to local building codes and potential shortages in technicians trained
to use them. Furthermore, these food retailers are concerned that
future regulation of PFAS could require retailers to change systems
again from certain compliant fluorinated refrigerants to others.\82\
Based on these concerns, food retailers requested additional time to
allow the technology and building codes to catch up. They requested
that the EPA move the compliance deadline for retail food remote
condensing units to the end of 2032 with an interim limit of 1,400
starting January 1, 2026.\83\
---------------------------------------------------------------------------

\81\ Id.
\82\ CO<INF>2</INF>, hydrocarbons, and ammonia are not
considered PFAS. The EPA notes that the Federal Government has not
adopted a specific definition of PFAS and has not included HFCs or
HFOs in any PFAS-related restrictions.
\83\ See trade association's presentation dated April 18, 2025,
in the docket for this action.
---------------------------------------------------------------------------

The EPA considered concerns from stakeholders in the retail food
industry to allow additional flexibility in refrigerant choice for
retail food remote condensing units, understanding there may be
challenges such as building codes to adopting newer technologies. Thus,
the EPA proposed a graduated schedule with an interim limit of 1,400
starting January 1, 2026, for new retail food remote condensing units
to allow additional flexibility for a limited period of time. Such
additional flexibility allows for the use of nonflammable options such
as R-448A and R-449A. As previously described, the EPA also proposed
limits of 150 or 300, depending on the characteristics of the system,
starting January 1, 2032, given that the Agency anticipated that the
period of the interim limit would be a sufficient amount of time for
implementation challenges to resolve.
2. Final Rule
The EPA is finalizing the graduated schedule for the use of HFCs in
new retail food remote condensing units similar to what was proposed.
Specifically, the EPA is relaxing the existing limit, on an interim
basis, to 1,400 upon the effective date of this rule, and limits of 150
or 300, depending on charge size or whether it is part of the high
temperature side of a cascade system, starting January 1, 2032. For
remote condensing units with a charge size of 200 pounds or more,
excluding the high temperature side of a cascade system, the limit is
150. For remote condensing unit systems with a charge size less than
200 pounds or remote condensing unit systems on the high temperature
side of a cascade system, the limit is 300. The limits of 150 or 300,
as described here, are the same limits as those promulgated with the
2023 Final Rule, just on an extended timeline. The EPA has reassessed
the factors under AIM Act subsection (i)(4) given the additional
information received ahead of the October 2025 Proposal and during the
comment period. The Agency concludes that the targeted relief in this
rule is appropriate given changes in our understanding of the
availability of substitutes, particularly with regard to building codes
and safety, and the overall economic costs. Similar to supermarket
systems, the interim limit temporarily allows for the use of a set of
certain refrigerants and reduces the burden on remote condensing unit
systems as they transition to new substitutes. The EPA also recognizes
that many remote condensing units are already using refrigerants that
would have complied with the 2023 Final Rule's limits. This rule does
not prevent anyone from choosing to use refrigerants below the limits
of 150 or 300 ahead of the new compliance requirements for new systems.
The Agency describes and responds to comments in section IV.D of this
preamble and the Response to Comments document in the docket.

E. Cold Storage Warehouses

The EPA is finalizing amendments to the limits for cold storage
warehouses to establish a graduated schedule with an interim limit of
700 upon the effective date of this rule, and 150 or 300, depending on
charge size or whether it is part of the high temperature side of a
cascade system, starting January 1, 2032.
1. Background
Cold storage warehouses are refrigerated facilities used for the
storage of temperature-controlled substances. Refrigeration systems
within cold storage warehouses can be divided into two categories:
packaged systems and central plant systems. Central plants are custom-
built refrigeration systems that are typically used in large,
refrigerated warehouses with cooling capacities that range from 20 to
5,000 kW. Central plant systems deliver cool air to the refrigerated
space through evaporators, which are typically suspended from the
ceiling in the refrigerated space. The evaporators are connected
through a piping network to multiple compressors located in a central
machine room, and a condenser, which is typically mounted outside near
the compressors. Central plant systems may have a direct or indirect
(secondary loop) design. Direct systems circulate a primary refrigerant
throughout the refrigerated space. In an indirect system, a primary
refrigerant cools a secondary refrigerant in the machine room, and the
secondary refrigerant is then circulated throughout the refrigerated
space.\84\
---------------------------------------------------------------------------

\84\ See 88 FR 73162 (October 24, 2023).
---------------------------------------------------------------------------

The 2023 Final Rule established restrictions on the use of HFCs in
new cold storage warehouses installed starting January 1, 2026. The
limit is 150 for systems with refrigerant charge capacities greater
than or equal to 200 pounds, and 300 for systems with refrigerant
charge capacities less than 200 pounds or for the high temperature side
of cascade systems irrespective of the total charge capacity.
The 2023 Final Rule would have required new cold storage warehouses
to be installed with refrigerants below a 150 or 300 limit, as
applicable, including ammonia, CO<INF>2</INF>, certain HFOs, or certain
HFC/HFO blends.\85\ While most cold storage warehouses had used ammonia
at the time, substitutes with lower toxicity and lower flammability
were still under development and had

[[Page 31296]]

not yet been listed by the SNAP program as acceptable for use in new
cold storage warehouses. While additional options were listed by SNAP
in June 2024,\86\ in advance of the January 1, 2026, compliance date,
the 2023 Final Rule would have largely made these newer refrigerant
blends, ammonia, or CO<INF>2</INF> the only options for new
installations of cold storage warehouses.
---------------------------------------------------------------------------

\85\ See 88 FR 73157 (October 24, 2023).
\86\ See 89 FR 50410 (June 13, 2024).
---------------------------------------------------------------------------

A new trade association submitted a request to the EPA on March 6,
2025, to adjust the limits for cold storage warehouses from 150 or 300,
as applicable, to 700. The trade association highlighted that ammonia,
a higher toxicity and flammable refrigerant, can present potential
safety concerns particularly when cold storage warehouses are not
located in isolated, unpopulated areas. The trade association cited a
number of recent examples of fatalities, injuries, and facility
evacuations related to the use of ammonia as a refrigerant in cold
storage warehouses in the United States.
The trade association's request was to adjust the limit for cold
storage to allow for the use of additional refrigerants, and in
particular, R-513A. The trade association identified R-513A as a
refrigerant in this subsector that met their safety, commercial
availability, energy efficiency, and usability requirements. The trade
association indicated that the substitutes identified by the EPA in the
2023 Final Rule would not necessarily be available in every situation
due to flammability or toxicity concerns, commercial availability,
decreased energy efficiency, not being mechanically practical due to
excessive displacement, building codes not being updated, and/or
economic costs.\87\
---------------------------------------------------------------------------

\87\ See request from trade association, dated March 6, 2025, in
the docket for this action.
---------------------------------------------------------------------------

The EPA also received information from another trade association
representing cold storage warehouses on June 9, 2025, in response to
the March 6, 2025, request, concerning a 2023 survey from the Global
Cold Chain Alliance (GCCA).\88\ That survey showed that over 90 percent
of cold storage warehouse refrigeration systems in the United States
used either ammonia or CO<INF>2</INF>.
---------------------------------------------------------------------------

\88\ See letter from trade association, dated June 9, 2025, in
the docket for this action.
---------------------------------------------------------------------------

The EPA proposed an interim limit of 700 starting January 1, 2026,
for new cold storage warehouses. Starting January 1, 2032, the EPA
proposed limits of 150 or 300, depending on the characteristics of the
system, as described previously. To balance near-term safety,
feasibility, and substitute availability, the EPA proposed an interim
limit of 700 for new cold storage warehouses to allow the use of
nonflammable, lower toxicity options such as R-513A, where ammonia or
alternatives with flammability designations are impractical due to
documented safety incidents, building code constraints, mechanical and
efficiency considerations, and/or supply-chain limitations. Beginning
January 1, 2032, the EPA proposed to lower the limit to 150 or 300, as
applicable in anticipation that building codes will be updated,
technologies will mature, and market availability of substitutes will
expand.
2. Final Rule
The EPA is finalizing the graduated schedule for the use of HFCs in
new cold storage warehouses similar to what was proposed. Specifically,
the EPA is amending the existing limit, on an interim basis, to 700,
upon the effective date of this rule, and limits of 150 or 300,
depending on charge size or whether it is part of the high temperature
side of a cascade system, starting January 1, 2032. For cold storage
warehouse systems with a charge size of 200 pounds or more, excluding
the high temperature side of a cascade system, the limit is 150. For
cold storage warehouse systems with a charge size less than 200 pounds,
or for the high temperature side of a cascade system, the limit is 300.
The limits of 150 or 300, as described here, are the same limits as
those promulgated with the 2023 Final Rule, just on an extended
timeline. The EPA has reassessed the factors under AIM Act subsection
(i)(4) given the additional information received ahead of the October
2025 Proposal and during the comment period. The Agency concludes that
the targeted relief in this rule is appropriate given changes in our
understanding of the availability of substitutes, and in particular a
need for additional non-flammable, lower toxicity alternatives in the
near term. The interim limit temporarily allows for the use of a set of
certain refrigerants and reduces the burden on cold storage warehouse
systems as they transition to new substitutes. The EPA also recognizes
that most cold storage warehouses are already using refrigerants that
would have complied with the 2023 Final Rule's limits, including
ammonia and CO<INF>2</INF>. This rule does not prevent anyone from
choosing to use refrigerants below the limits of 150 or 300 ahead of
the new compliance requirements for new systems.
While entities in many areas of the United States can and do use
substitute refrigerants in this subsector, the EPA acknowledged in the
proposal that factors such as the use of ammonia in a system containing
thousands of pounds of refrigerant charge could pose a safety risk in
densely populated areas if a leak were to occur, or if such a system
were to be handled improperly and could hinder compliance on a
nationwide scale, including in densely populated areas. The Agency
describes and responds to comments in section IV.E of this preamble and
the Response to Comments document in the docket.

F. Replacement Condensing Units in the Residential and Light Commercial
Air Conditioning and Heat Pump Subsector

The EPA did not propose and is not finalizing changes to the
treatment of new condensing units used as replacements in the
residential and light commercial AC/HP subsector.
1. Background
The residential and light commercial AC/HP subsector includes many
types of equipment, from self-contained products such as packaged
terminal air conditioners and window AC units to unitary split systems
such as ducted and non-ducted mini-splits, multi-splits, and ducted air
conditioners and heat pumps. This section pertains only to the
treatment of condensing units used in split AC/HP systems, including
mini-splits and multi-splits, that are field assembled and charged.
These systems consist of an outdoor unit with a condenser and a
compressor, refrigerant lines, and an indoor unit with an evaporator.
The evaporator and air handler may, or may not, be connected to ducts
to carry conditioned air throughout a building.
The unit in which the condenser and compressor are packaged
together is called a ``condensing unit.'' The condensing unit
discharges heat and is typically located outside. ASHRAE defines a
condensing unit as a ``machine designed to condense refrigerant vapor
to a liquid by compressing the vapor in a positive displacement
compressor and rejecting heat to a cooling medium. A condensing unit
usually consists of one or more positive displacement compressors and
motors, condensing coils, liquid receivers, and other devices mounted
on a common base.'' \89\
---------------------------------------------------------------------------

\89\ See ASHRAE Terminology in the docket for this action, and
at <a href="https://terminology.ashrae.org">https://terminology.ashrae.org</a>.
---------------------------------------------------------------------------

In proposing the 2023 Final Rule (hereinafter ``Proposed 2023
Rule'') the EPA proposed that restrictions would apply to ``products,''
which would have

[[Page 31297]]

included condensing units.\90\ Specifically, the proposal stated,
``effective January 1, 2025, no person may manufacture or import any
product . . . as listed in Sec. 84.56(a)'' (emphasis added).\91\
Likewise, ``effective January 1, 2026, no person may sell or
distribute, offer to sell or distribute, make available to sell or
distribute, purchase or receive, attempt to purchase or receive, or
export any product . . . as listed in Sec. 84.56(a)'' (emphasis
added). The proposed definition of ``product'' in 40 CFR 84.56(a) would
have contained a non-exhaustive list that included ``equipment,
appliances, components, [and] subcomponents.'' A condensing unit is a
component of the larger unitary split AC/HP system and therefore, under
the proposed rule, would have been subject to restrictions. Under that
proposal, the condenser and compressor housed within a condensing unit
would have been considered either components or subcomponents and would
have been subject to restrictions.
---------------------------------------------------------------------------

\90\ See 87 FR 76738 (December 15, 2022).
\91\ 40 CFR 84.56(a)(24) lists ``Residential and light
commercial air-conditioning and heat pump systems, when using or
intended to use a regulated substance or a blend containing a
regulated substance with a global warming potential of 700 or
greater, except for variable refrigerant flow air-conditioning
systems.'' The Proposed 2023 Rule did not distinguish between
``products'' and ``systems'' like the 2023 Final Rule.
---------------------------------------------------------------------------

The EPA received many comments on the Proposed 2023 Rule expressing
concern about the impact of restricting components and subcomponents
using legacy refrigerants. The comments were almost universally
opposed, with the specific concerns varying on the type of restriction
placed on the component, including: manufacture and import; sale and
distribution; and the purchase and use to maintain existing equipment.
Most comments were made in the context of refrigeration systems, such
as supermarket systems, which contain numerous components, including
multiple compressors on a rack, that are commonly replaced to keep the
expensive and complex systems operational. One comment made in the
context of AC systems expressed concern about the ability to honor
warranties for existing systems without replacement components. Based
on the concern expressed by commenters, the Agency removed components
and subcomponents from the final definition of ``product.'' Instead,
the final rule classified condensing units as one of five ``specified
components'' at 40 CFR 84.52 to make clear that they were not subject
to the restrictions on manufacture, import, sale, distribution, or
export and thus allow for the continued servicing and maintenance of
existing equipment. The EPA prohibited specified components using
legacy refrigerant to be installed as new systems after the applicable
installation compliance date.
After finalization of the 2023 Final Rule, the EPA received two
administrative petitions, one from a chemical manufacturer and the
other from a group of trade associations, requesting that the Agency
reconsider that final rule as it applies to the residential and light
commercial AC/HP subsector. The two administrative petitions requested
reconsideration of separate provisions of the regulations as means to
achieve a similar outcome, that is, reconsideration of the treatment of
condensing units used as replacements in existing systems.
The administrative petition from the chemical manufacturer
requested that the EPA remove provisions that allow the continued use
of specified components that use regulated substances above the 700
limit in the residential and light commercial AC/HP subsector. The
petitioner stated that the EPA did not propose a definition of
``specified component,'' nor did it propose to exempt specified
components from the HFC use prohibitions. The petitioner noted that the
EPA proposed the opposite by including components and subcomponents in
the list of products subject to the proposed restrictions. The
petitioner stated that the final rule allows for unlimited replacement
of condensers, evaporators, and compressors in this subsector, thereby
extending the life of existing systems beyond their designed lifetimes
without taking comment on the impacts of such extended use. In meetings
with the EPA regarding the petition, the petitioner clarified that its
concern was limited to the replacement of condensing units used in
split AC systems in the residential and light commercial AC/HP
subsector, not the other four specified components, nor condensing
units used in refrigeration subsectors.\92\
---------------------------------------------------------------------------

\92\ See Memorandum--EPA Meetings Related to the Technology
Transitions Reconsideration Notice of Proposed Rulemaking in the
docket for this action.
---------------------------------------------------------------------------

The administrative petition from the group of trade associations
requested that the EPA make a determination that replacing certain
condensing units in the residential and light commercial AC/HP
subsector would be considered the installation of a new system under 40
CFR 84.54(e). The administrative petition is limited to condensing
units in this subsector that are designed for use with a single
condenser and a single evaporator. The administrative petition
requested that the EPA not restrict condensing units used in variable
refrigerant flow (VRF) systems,\93\ multi-split systems, and commercial
AC systems with more than one condenser and/or more than one
evaporator. After submitting their initial administrative petition, the
group of trade associations submitted a letter to the EPA containing
supplemental information that limited their request to condensing units
with a capacity less than 65,000 BTUs.\94\
---------------------------------------------------------------------------

\93\ See 88 FR 73178 for a description of VRF systems.
\94\ See supplemental letter from trade associations, dated
April 30, 2024, in the docket for this action.
---------------------------------------------------------------------------

In the proposal for this rule and in response to stakeholder
administrative petitions, the EPA proposed to retain the requirements
established by the 2023 Final Rule regarding the treatment of
condensing units used in the residential and light commercial AC/HP
subsector. The proposal provided an opportunity for the public to
comment on the treatment of condensing units in this subsector and in
doing so, the EPA noted it was addressing one petitioner's concerns
about their inability to comment on changes made between proposal and
finalization of the 2023 Final Rule regarding the treatment of
components.
2. Final Rule
In this final rule, the EPA is not making any changes to the
treatment of new condensing units in the residential and light
commercial AC/HP subsector. This includes no change to the definitions
at 40 CFR 84.52, the installation restriction at 40 CFR 84.54(c)(1),
the list of actions that the EPA considers an installation of a new
system at 40 CFR 84.54(e), the exemption for components at 40 CFR
84.56(b), or the labeling, reporting, and recordkeeping requirements
applicable to specified components. Allowing a continued market (i.e.,
manufacture, import, export, sale, or distribution) for specified
components enables end-users to maintain their existing systems, even
if those systems use legacy HFC refrigerants. By making no changes to
the current regulations, a homeowner can choose to replace their failed
condensing unit rather than purchase a whole new system. The EPA's
decision to not change the treatment of condensing units aligns with
subsection (i)(7)(B) of the AIM Act and consistent with the Agency's
historical practice of allowing repair of legacy equipment throughout
its useful life. This final decision is also consistent with the

[[Page 31298]]

Presidential Memorandum titled Delivering Emergency Price Relief for
American Families and Defeating the Cost-of-Living Crisis, which
directs ``the heads of all executive departments and agencies to
deliver emergency price relief, consistent with applicable law, to the
American people and increase the prosperity of the American worker,''
including by ``pursuing appropriate actions to . . . eliminate
counterproductive requirements that raise the costs of home
appliance[.]'' If restrictions were to be placed on replacing the
condensing unit, the owner's only recourse would be to replace the
entire system. Installing a new system is more costly than replacing
just the condensing unit, particularly if the system is relatively new,
and in some instances, warranties or insurance will only cover the
replacement of like equipment. The Agency describes and responds to
comments in section IV.F of this preamble and the Response to Comments
document in the docket.

G. Industrial Process Refrigeration in Certain Laboratory Equipment

The EPA is finalizing provisions related to certain laboratory
equipment within the industrial process refrigeration subsector. This
final rule extends the compliance date for refrigerated centrifuges and
laboratory shakers to January 1, 2028.
1. Background
a. Refrigerated Centrifuges
A refrigerated centrifuge is a laboratory device that spins samples
at a high speed while keeping them at a low, controlled temperature.
Refrigerated centrifuges are a niche subset of equipment used in
laboratories and have narrow technical requirements which limit the
refrigerants that can be used. The EPA understands that refrigerated
centrifuges are critical for blood processing and other essential
pharmaceutical and medical industries.
The 2023 Final Rule included refrigerated laboratory equipment
within the IPR subsector.\95\ Specifically, the 2023 Final Rule stated
that refrigerated laboratory equipment covered by either the 2nd
edition of the UL 61010-2-011 standard or the 2nd edition of the UL
60335-2-89 standard are subject to the restrictions in the rule.\96\
The restrictions on the use of HFCs and HFC blends in new IPR equipment
vary based on the lowest temperature at which the equipment is designed
to operate, charge size, and the configuration of the equipment. IPR
equipment with refrigerants entering the evaporator at temperatures
between -50 [deg]C and -30 [deg]C have a compliance date of January 1,
2028, while IPR equipment with refrigerants entering the evaporator at
temperatures at or above -30 [deg]C have a compliance date of January
1, 2026. These restrictions are codified at 40 CFR 84.54(a)(12) and
84.54(c)(10).
---------------------------------------------------------------------------

\95\ The EPA is not aware of IPR centrifuge configurations used
for laboratory applications that would be covered by the IPR chiller
subsector as opposed to the IPR subsector at 40 CFR 84.54(a)(10),
(c)(5), or (c)(6).
\96\ See p. 209 of the Response to Comments document for the
2023 Final Rule.
---------------------------------------------------------------------------

The 2023 Final Rule excluded centrifuges with charge sizes above
the threshold consistent with UL 61010-2-011. The EPA recognized that
refrigerated centrifuges that contain less than 150 g of flammable
refrigerant charge (or 370 g of nonflammable refrigerant charge) can
meet the UL standards using refrigerants below the limits for IPR and
are subject to the HFC use restriction. Conversely, the EPA recognized
that refrigerated centrifuges that require more refrigeration capacity
than can be achieved using refrigerants that meet the HFC use
restrictions while meeting the charge size limits in UL 61010-2-011 are
not restricted. This is because the refrigerants that meet the IPR
restrictions are either flammable, have a higher toxicity, or have
higher pressure than other available refrigerants, and as such, either
require an upper limit on charge size to meet the UL standard's safety
requirements or are outside the current scope of the UL standard
altogether.
After issuance of the 2023 Final Rule, a manufacturer contacted the
EPA concerning refrigerated centrifugal equipment that follows UL
61010-2-011 or UL 61010-2-020. The manufacturer stated that
refrigerated centrifuges need to be tested to American National
Standards Institute (ANSI)/UL standards 61010-2-011 or 61010-2-020
before mass production. The manufacturer described how UL 61010-2-020
requires a particular test for refrigerated centrifuges called the
Maximum Credible Accident (MCA) test which assesses the safety of
centrifugal equipment in a worst-case mechanical failure. The test
simulates an accident scenario where the rotor assembly, a high-speed
spinning part of the centrifuge, experiences catastrophic failure or
becomes detached during rotation. This test ensures that the design and
structure of the equipment are robust enough to contain debris and
prevent personnel from hazardous exposure in such an event. The
manufacturer explained that the MCA test itself is currently not
designed in a manner that allows for testing of flammable or high-
pressure refrigerants.
The EPA understands that this update to the UL safety testing
procedure impacts all centrifuge manufacturers. The manufacturer noted
that the MCA test was expected to be updated in 2025, before the
January 1, 2026, compliance date, but that additional time would be
needed for manufacturers to redesign, test, and certify centrifuges to
the revised standards. The manufacturer later stated in a meeting that
they anticipate that standards and equipment will be updated by January
1, 2028.\97\ The EPA understands that as of February 2026, the updates
to UL 61010-2-020 have not yet been finalized to accommodate testing
refrigerated centrifuges with the MCA test using flammable and high-
pressure refrigerants. While the EPA does not know when the updates
will be completed, we have no information to suggest it will not be
completed by January 1, 2028.
---------------------------------------------------------------------------

\97\ See Memorandum--EPA Meetings Related to the Technology
Transitions Reconsideration Notice of Proposed Rulemaking in the
docket for this action.
---------------------------------------------------------------------------

The EPA proposed and is now finalizing an extension of the
compliance date for refrigerated laboratory centrifuges within the IPR
subsector from January 1, 2026, to January 1, 2028. This extension
allows additional time for the industry standard setting process to
finalize updated test procedures specific to refrigerated centrifuges
so that new refrigerants can be safely deployed for use in this niche
application.
b. Refrigerated Laboratory Shakers
Laboratory shakers are specialized pieces of equipment used in
scientific and medical laboratories to continuously agitate liquid
biological samples at controlled temperatures. These devices are
designed for applications that require temperature-sensitive
conditions, such as growing microbial cell cultures or eukaryotic
tissue cultures. The temperature range can span in some applications
from around 4 [deg]C to 80 [deg]C.
The 2023 Final Rule indicated that refrigerated laboratory
equipment that use an HFC or blend containing HFC(s) are regulated
within the IPR subsector.\98\ Refrigerated laboratory shakers are
covered by the UL 60335-2-89 standard

[[Page 31299]]

and are regulated as a part of this subsector.
---------------------------------------------------------------------------

\98\ The EPA is not aware of IPR shaker configurations used for
laboratory applications that would be covered by the IPR chiller
subsector as opposed to the IPR subsector at 40 CFR 84.54(a)(10),
(c)(5), or (c)(6).
---------------------------------------------------------------------------

Under the regulations at 40 CFR 84.54, IPR equipment with
refrigerants entering the evaporator at temperatures at or above -30
[deg]C have a compliance date of January 1, 2026. After issuance of the
2023 Technology Transition Rule, a manufacturer contacted the EPA
regarding refrigerated laboratory shaker equipment. The manufacturer
stated that there are currently limited alternatives for small, compact
IPR systems, such as laboratory shakers.\99\ The manufacturer noted
that while there are some non-HFC alternatives currently on the market
in some laboratory equipment applications, such as R-290 \100\ and R-
1234yf, these alternatives pose safety, efficiency, and cooling
capacity challenges in compact lab environments and in certain
laboratory applications. For example, flammability is a particular
concern from both a regulatory and safety perspective, as laboratories
often have open flames, solvents, or other electronics present that
could trigger an ignition.
---------------------------------------------------------------------------

\99\ See materials from manufacturer at EPA-HQ-OAR-0005-0007.
\100\ Commonly known as propane.
---------------------------------------------------------------------------

Since laboratory shakers are used in various cell culture
applications, the manufacturer also described how a wide temperature
operation range and precise temperature control are crucial to ensure
optimal cell growth conditions and experimental accuracy. A temperature
operation range that extends as low as 4 [deg]C and up to 80 [deg]C
allows for a range of biological laboratory research applications. The
manufacturer indicated that currently R-134a is the only refrigerant
used that can achieve such a wide temperature range. Not all shakers
have this wide temperature range, and in particular, some do not extend
as high as 80 [deg]C. Shakers that use R-600a \101\ or a Peltier
cooling method \102\ can operate at temperatures as high as 60 [deg]C.
This limits the capability of such shakers from operating at
temperatures above 60 [deg]C, in which certain niche research processes
are conducted.
---------------------------------------------------------------------------

\101\ Commonly known as isobutane.
\102\ Peltier cooling uses a thermoelectric effect for cooling.
It does not contain refrigerant.
---------------------------------------------------------------------------

While a range of options are used to control temperature in
laboratory shakers, including compliant refrigerants that can meet the
requirements in some refrigerated laboratory shaker applications, there
remain some use cases in which compliant refrigerants are unable to
meet the requirements. The manufacturer noted that temperature accuracy
to within 0.1 [deg]C is required to maintain the integrity of the cell
cultures and reliability of results in certain research
applications.\103\ The manufacturer shared information that illustrated
how not all shakers have this precise temperature control capability.
Some laboratory shakers can provide an accuracy within 0.3 [deg]C, and
some of those are already using compliant refrigerants, including R-
600a.
---------------------------------------------------------------------------

\103\ See materials from manufacturer at EPA-HQ-OAR-0005-0007.
---------------------------------------------------------------------------

The manufacturer noted that one feasible alternative that could
achieve desired temperature specifications is CO<INF>2</INF>, but that
current IPR systems for this refrigerant are primarily designed for
large-scale industrial refrigeration systems and that there are limited
solutions for small-scale laboratory equipment. Systems are currently
in development but are not expected to be available until mid-2027 at
the earliest.\104\
---------------------------------------------------------------------------

\104\ See materials from manufacturer at EPA-HQ-OAR-0005-0007.
---------------------------------------------------------------------------

The EPA proposed and is now finalizing an extension of the
compliance date for refrigerated laboratory shakers within the IPR
sector from January 1, 2026, to January 1, 2028. This extension is to
allow additional time for the safe deployment of new refrigerants and
not-in-kind substitutes (e.g., Peltier cooling) for use in this niche
refrigerated laboratory application.
2. Final Rule
The EPA is extending the compliance date to January 1, 2028, for
refrigerated laboratory centrifuges and refrigerated laboratory shakers
within the IPR subsector. This extension does not apply to other types
of equipment in the IPR subsector or to refrigerated laboratory
equipment not discussed in this action. After reviewing public comments
received during the comment period, the EPA is finalizing this
extension as proposed.
a. Refrigerated Centrifuges
Comments received on the October 2025 Proposal reiterated
information received from requests to reconsider the compliance
deadline for refrigerated laboratory centrifuges finalized in the 2023
Final Rule. This extension allows additional time for the industry
standard setting process to finalize updated test procedures specific
to refrigerated centrifuges so that new refrigerants can be safely
deployed for use in this niche application. The EPA did not receive
adverse comments opposing the proposal.
The EPA has reassessed the four factors under AIM Act subsection
(i)(4) given the additional information received ahead of the October
2025 Proposal and during the comment period. Based on comments and the
information provided by manufacturers, the Agency agrees that the MCA
test required in UL 61010-2-020 cannot be performed until modifications
are made to accommodate the safety risks associated with fire hazards,
ballistic threats, or toxicity hazards and understands that the
standards and equipment updates are expected to be completed by January
1, 2028. Therefore, the EPA concludes that the targeted relief in this
rule is appropriate given changes in our understanding of the
availability of substitutes and is extending the compliance date to
January 1, 2028, for refrigerated centrifuges within the IPR subsector.
The Agency describes and responds to comments in section IV.G of this
preamble and the Response to Comments document in the docket.
b. Refrigerated Laboratory Shakers
Comments received on the October 2025 Proposal reiterated
information received from requests to reconsider the compliance
deadline for refrigerated laboratory shakers finalized in the 2023
Final Rule. This extension is to allow additional time for the safe
deployment of new refrigerants and not-in-kind substitutes (e.g.,
Peltier cooling) for use in this niche refrigerated laboratory
application. The EPA did not receive adverse comments opposing the
proposal.
The EPA has reassessed the factors under AIM Act subsection (i)(4)
given the additional information received ahead of the October 2025
Proposal and during the comment period. Based on comments and the
information provided by manufacturers, the Agency acknowledges that
several refrigerants are currently being used in refrigerated
laboratory shakers but that they do not all have the same temperature
operation range or control capacity. The Agency is also aware that
CO<INF>2</INF> is being developed for use in laboratory shakers to have
the necessary specifications that can meet manufacturers and
researchers' requirements in time before 2028. As such, the EPA
concludes that the targeted relief in this rule is appropriate given
changes in our understanding of the availability of substitutes and is
extending the compliance date from January 1, 2026, to January 1, 2028,
for all refrigerated laboratory shakers, to provide additional time for
compliant refrigerant options to be developed for refrigerated
laboratory shaker uses. The

[[Page 31300]]

Agency describes and responds to comments in section IV.G of this
preamble and the Response to Comments document in the docket.

H. Preventing Stranded Inventory of Residential and Light Commercial
Air Conditioning and Heat Pump Equipment

The EPA is finalizing, as proposed, the removal of the deadline for
installing residential and light commercial AC/HP systems when using
equipment that was domestically manufactured or imported into the
United States before January 1, 2025.
1. Background
The 2023 Final Rule restricted installation of new residential and
light commercial AC/HP systems using refrigerants above a limit of 700
beginning January 1, 2025. Systems in this subsector include unitary
split systems such as ducted and non-ducted mini-splits, multi-splits,
and ducted air conditioners and heat pumps.
After that rule was finalized, the EPA received information
including data concerning how the January 1, 2025, installation date
restriction would result in substantial stranded inventory for
residential new construction, including both single-family and multi-
family dwellings, where builders order heating and cooling equipment
well in advance of knowing the exact date of installation. The EPA
published an IFR on December 26, 2023, to address the unique
circumstances of this subsector to prevent equipment from being
stranded.\105\ That rule extended the installation compliance date for
such systems by one year, to January 1, 2026, so long as the equipment
was manufactured in the United States or imported into the United
States before January 1, 2025. Since publication of the IFR, other
entities requested additional time beyond January 1, 2026, to install
residential and light commercial AC/HP systems.\106\ These requesters
shared that additional time is needed because of construction delays
particularly for certain large construction projects (e.g., for
multifamily housing) that have long timelines.\107\ Without further
extension of the installation compliance date, they noted that there
could still be stranded inventory of equipment domestically
manufactured or imported before 2025.
---------------------------------------------------------------------------

\105\ See 88 FR 88825 (December. 26, 2023).
\106\ See comment on the IFR (88 FR 88825 (December. 26, 2023))
from the National Multifamily Housing Council and National Apartment
Association, as well as a list of stakeholders who submitted
relevant questions and comments to the EPA, both at EPA-HQ-OAR-0005-
0007.
\107\ See comment on the IFR (88 FR 88825 (December. 26, 2023))
from the National Multifamily Housing Council and National Apartment
Association at EPA-HQ-OAR-0005-0007.
---------------------------------------------------------------------------

In addition, at the time of the 2023 Final Rule, the EPA understood
that substitutes, including R-454B and R-32, were being developed and
deployed. The rate of new installations that used these substitutes has
increased significantly, in particular in 2025.\108\ This left larger
inventories than expected of equipment using refrigerants above the 700
limit at risk of being stranded.
---------------------------------------------------------------------------

\108\ See HARDI press release, ``A2L Equipment Reaches 90% of
Market Share as Cooling Season Ends,'' November 19, 2025, in the
docket for this action.
---------------------------------------------------------------------------

Further, the EPA observed that the transition to equipment in the
residential and light commercial AC/HP subsector using compliant
refrigerants, including R-454B, saw unexpected supply issues during
deployment.\109\ While there was a sufficient supply of R-454B, there
were challenges supplying the refrigerant in service cylinders to
contractors and technicians, resulting in R-454B scarcity in some
regions. In particular, some contractors and technicians had
difficulties securing R-454B refrigerant in the field to charge these
units during installation.
---------------------------------------------------------------------------

\109\ See Memorandum--Overview of R-454B Refrigerant Shortage
and Current Status, in the docket for this action.
---------------------------------------------------------------------------

The EPA proposed to remove the installation compliance date for the
residential and light commercial AC/HP subsector if the components were
manufactured domestically or imported into the United States before
January 1, 2025, to avoid stranded inventory. The EPA also considered
extending the installation compliance date to January 1, 2027, as an
alternative means by which to also avoid stranding inventory.
2. Final Rule
The EPA is finalizing, as proposed, the removal of the deadline for
installing residential and light commercial AC/HP systems that use
specified components that were domestically manufactured or imported
into the United States before January 1, 2025.
The EPA has reassessed the factors under AIM Act subsection (i)(4)
given the additional information received ahead of the October 2025
Proposal and during the comment period. The EPA proposed and is now
finalizing this provision to provide additional options to support
consumers given the specific circumstances discussed in this section
and in section IV.H of this preamble concerning the introduction of R-
454B equipment ahead of 2026 and the resulting supply chain issues
observed in 2025. Removing the installation compliance date allows for
the installation of the remaining inventory of R-410A equipment that
had been manufactured in the United States or imported into the United
States before January 1, 2025, for use in this subsector, which could
be a lower cost option for consumers. The EPA does not expect there to
be discernible impacts from those already modeled in the analysis for
the 2023 Final Rule, since the total number of systems available for
installation using legacy refrigerants would match what the Agency
modeled for that rule. The EPA concludes that the targeted relief in
this rule is appropriate given changes in our understanding of the
supply chain issues that resulted in more limited availability of
substitutes than was anticipated and overall economic costs. The Agency
describes and responds to comments in section IV.H of this preamble and
the Response to Comments document in the docket.

I. Labeling Correction

The EPA is finalizing the correction of an erroneous citation in
the regulatory text at 40 CFR 84.58(b). The regulatory text now
correctly directs the reader to paragraph (d), not to paragraph (c).

J. Effective Date of Rules Under Paragraph (i)(6)

The EPA is making this final rule effective 60 days after
publication in the Federal Register, as proposed.
Subsection (i)(6) of the AIM Act states that ``no rule under this
subsection may take effect before the date that is 1 year after the
date on which the Administrator promulgates the applicable rule under
this subsection.'' \110\ The best reading of this statutory text is
that the one-year clock begins upon promulgation of the ``applicable
rule'' that established the restrictions at issue--here, the 2023 Final
Rule, which invoked the EPA's discretionary authority under subsection
(i) for the first time to establish the restrictions at issue in this
reconsideration action. In other words, the one-year effective date
delay requirement does not apply to subsequent rules that are
unambiguously less stringent than the existing restrictions, including
the relaxation or removal of existing restrictions.
---------------------------------------------------------------------------

\110\ See 42 U.S.C. 7675(i)(6).
---------------------------------------------------------------------------

The 2023 Final Rule described the EPA's interpretation of
subsection (i)(6) of the AIM Act as applying to the

[[Page 31301]]

establishment of restrictions on the use of HFCs under subsection
(i)(1) of the AIM Act. Based on that interpretation, the Agency
established compliance dates for the restrictions on the domestic
manufacture and import of products and installation of systems that
were at least one year from the date of promulgation. At the same time,
we did not delay compliance or effective dates for provisions
pertaining to program administration and petitions processing and
elected to make those provisions effective 60 days after publication in
the Federal Register.\111\ Thus, in the 2023 Final Rule, the Agency
recognized that subsection (i)(6) does not require a one year delayed
effective date for all regulatory actions under subsection (i).
---------------------------------------------------------------------------

\111\ See 88 FR 73104 (October 24, 2023).
---------------------------------------------------------------------------

This interpretation flows from the statutory text of subsection
(i)(6): ``No rule under this subsection may take effect before the date
that is 1 year after the date on which the Administrator promulgates
the applicable rule under this subsection.'' \112\ Congress's inclusion
of the word ``applicable'' makes it clear that the ``rule under this
subsection'' referred to at the beginning of the sentence may be
different in at least some cases than the ``applicable rule under this
subsection'' referenced at the end. The canon against surplusage argues
that every word and phrase in a statute should be assumed to have an
effect. If this section was drafted with the intent that the two rules
referenced are always one and the same--i.e., that the effective date
requirement applies to any rule--the word ``applicable'' could be
simply struck from the text and the meaning would remain the same: ``No
rule under this subsection may take effect before the date that is 1
year after the date on which the Administrator promulgates the [ ] rule
under this subsection.''
---------------------------------------------------------------------------

\112\ See 42 U.S.C. 7675(i)(6).
---------------------------------------------------------------------------

Assuming that the word ``applicable'' means something, the best
interpretation of the statutory text in this provision is that the
``applicable'' rule is a rule that creates new restrictions for a
particular sector or subsector, which is when a one-year delay
accomplishes Congress's objectives. Providing a full year delay between
promulgation and application of a compliance deadline is important when
a new sector or subsector is being regulated, as with the 2023 Final
Rule, to provide regulated parties sufficient notice to plan for and
adjust to new restrictions. However, when the EPA is revising an
existing restriction by, for example, providing additional time for
compliance or changing a temperature threshold to make the previously
existing restriction less stringent, the need for adequate notice to
parties subject to the restriction is less compelling. In that case,
the ``applicable rule'' is the rule that created the original
restrictions, not a subsequent rule making the restrictions less
stringent. That interpretation is consistent with the purpose of
subsection (i)--authorizing the EPA to manage the transition toward
non-HFC substitutes while ensuring that implementation is not unduly
disruptive--and with general principles of administrative law.\113\
This interpretation also aligns best with the text and structure of
subsection (i), which contemplates the remaining provisions of
subsection (i) applying to rules creating restrictions: ``the
Administrator may by rule restrict, fully, partially, or on a graduated
schedule, the use of a regulated substance in the sector or subsector
in which the regulated substance is used.'' \114\ The Agency therefore
finds the best reading of the effective date provision in subsection
(i)(6) as not restarting the one-year delay in effective date upon
promulgation of the adjustments in this rulemaking that provide relief
from existing restrictions originally promulgated in the 2023 Final
Rule. The provision would still require a one-year delay in effective
date for the creation of any new restrictions, whether in the sectors
or subsectors covered by the 2023 Final Rule or otherwise, as that
would be an ``applicable rule'' under subsection (i)(6).
---------------------------------------------------------------------------

\113\ Congress has long recognized in the Administrative
Procedure Act, for example, the distinction between ``a substantive
rule'' that ``relieves a restriction'' and one that does not for
effective-date purposes. 5 U.S.C. 553(d)(1). See Indep. U.S. Tanker
Owners Comm. v. Skinner, 884 F.2d 587 (D.C. Cir. 1989) (effective
date requirement did not apply even when a waiting period would have
benefited third parties).
\114\ See 42 U.S.C. 7675(i)(1) (emphasis added).
---------------------------------------------------------------------------

Since finalizing the 2023 Final Rule, the EPA has issued two rules
under subsection (i) of the AIM Act that adjusted existing restrictions
based on new information. In those rules, we made changes to the
requirements under subsection (i), including extending compliance
dates, at least one year before the restriction taking effect.\115\ To
the extent those previous rules took a position to the contrary, the
Agency has reconsidered its position and finds that the best reading of
subsection (i)(6) is that the one-year clock begins upon promulgation
of the ``applicable rule'' at issue, and does not begin again upon
promulgation of a rule modifying existing restrictions that were
originally promulgated under subsection (i) if those modifications
provide relief from a restriction.
---------------------------------------------------------------------------

\115\ See 88 FR 88826 (December 26, 2023); 89 FR 100381
(December 12, 2024).
---------------------------------------------------------------------------

IV. Comments and Responses

This section of the preamble presents a summary of, and the EPA's
responses to, the significant comments received on the October 2025
Proposal for the topics addressed in each subsection. The EPA's full
response to comments on the October 2025 Proposal, including any
comments not discussed in this preamble, is available in the EPA's
Response to Comments (RTC) document for this final rule.

A. Refrigerated Transport--Intermodal Containers

Comment: Commenters that addressed this provision were generally
supportive of the EPA's proposal to raise the temperature threshold.
Many commenters noted that this was a targeted change based on new data
that properly differentiates low-temperature transport refrigeration
equipment that has unique technical challenges from other equipment.
One commenter indicated this adjustment is tailored, technically
justified, and administratively sound. Another commenter described this
change as a ``technical tweak'' that relaxes an overly stringent use
condition and does not introduce any new restrictions.
Response: The EPA agrees with the commenters that supported the
proposal for reasons that include it is tailored, technically
justified, administratively sound, and a technical adjustment.
Comment: A few commenters disagreed with the Agency's proposal. One
commenter suggested that the threshold be -40 [deg]C since intermodal
containers that use compliant refrigerants at that temperature have
been commercially available on the global market for more than a
decade. This commenter also did not believe that there is a significant
distinction between the temperature needs of deep frozen versus fresh
and frozen cargo in the -35 [deg]C to -40 [deg]C range, and that most
critical life sciences products such as blood plasma and
pharmaceuticals require temperatures below -50 [deg]C. A few commenters
who were generally opposed to any relaxing of the requirements of the
2023 Final Rule were opposed to changing the temperature threshold due
to environmental impacts. One commenter suggested that relief could be
time-limited. This commenter noted that if the relief is provided for
the purpose of shipping critical materials, then the

[[Page 31302]]

reliable supply of refrigerant is also critical.
Response: The EPA disagrees with commenters who opposed changing
the temperature threshold for refrigerated transport intermodal
containers. These commenters did not provide technical information to
counter the information cited in the proposed rule that demonstrated
the need for a change given a lack of available refrigerants that would
be effective at this low temperature range.
The EPA disagrees with the suggestion of a temporary change to this
restriction as the Agency does not have information at this time
indicating when an alternative will be available that would meet the
limit established in the 2023 Final Rule which could meet the needs of
intermodal refrigerated transport equipment in this temperature range.
Given the transportation conditions necessary for shipping blood
plasma, pharmaceuticals, temperature-sensitive enzymes, dangerous
goods, and other materials at temperatures below -35 [deg]C, the EPA
agrees to provide targeted relief. However, to the extent that
alternatives are developed in the future, the Agency may consider a
rulemaking to restrict the use of legacy refrigerants. The EPA also
disagrees with one commenter's request to change the temperature
threshold to -40 [deg]C. While this commenter indicated that there is
not a significant distinction between the temperature needs of cargo in
the -35 [deg]C to -40 [deg]C range, the commenter did not provide
technical information to support the change, such as which
refrigerant(s) or any supporting documentation. The lack of a
distinction between -35 [deg]C and -40 [deg]C supports the Agency's
decision.
The EPA also clarifies that the lowest temperature at which
equipment is designed to operate determines whether it is subject to
use restrictions. This means that if a refrigerated transport--
intermodal container is designed to achieve a box temperature below -35
[deg]C, it would not be subject to restrictions even if at times the
container is operated at temperatures at or above -35 [deg]C.
Comment: Several commenters who addressed this provision in their
comments confirmed that utilizing box temperature is the standard
industry practice for designing, marketing, and selling refrigeration
equipment used in intermodal refrigerated transport, and no commenter
opposed the Agency's proposal to change the temperature measurement
location.
Response: The EPA is finalizing the box temperature as the point of
temperature measurement to better align with common industry practice.

B. Industrial Process Refrigeration and Chillers for Industrial Process
Refrigeration in Semiconductor Manufacturing

Comment: Commenters that addressed this provision in their comments
were generally supportive of the Agency's proposal. Commenters in the
semiconductor manufacturing industry agreed with the charge size
threshold of 100 pounds or less for SMRE and stated that the proposal
correctly recognizes the additional time needed to design, test,
qualify, validate, and deploy the type of specialty equipment used in
semiconductor manufacturing. Two commenters noted that the proposal
appropriately accounts for long qualification cycles and complex supply
chain integration that is unique to the industry.
Response: The EPA acknowledges commenters' support for the
rationale behind the proposed revisions and is finalizing as proposed.
Comment: One commenter described the impacts if additional time to
transition is not provided. This commenter stated there could be supply
chain disruptions that could cascade across industries dependent on
advanced chips, including automotive, telecommunications, energy
production, and defense manufacturing. This commenter further noted
that semiconductor manufacturing is uniquely capital-intensive, and
even temporary interruptions can reverberate globally and cause
shortages and price volatility.
Response: The EPA agrees with the semiconductor manufacturers'
concerns, particularly for potential downtime and that such downtime
could have impacts on critical industries and national security. Given
the information provided on more time to test, qualify, and validate
substitutes, the EPA is providing until January 1, 2030, as described
above.
Comment: One commenter stated the contribution of SMRE to overall
HFC emissions is minimal, estimated at less than one-tenth of one
percent of annual U.S. greenhouse gas emissions. Several commenters who
were generally opposed to relaxing the requirements of the 2023 Final
Rule due to impacts on the environment were opposed to this proposal.
Response: The EPA agrees that any potential impacts on HFC
emissions would be minimal. The EPA also notes that the statute directs
the Agency to factor in to the extent practicable the factors listed in
subsection (i)(4) which includes the availability of substitutes, among
other things. Based on the totality of the record for this rulemaking,
and in particular the information on alternatives, the Agency has
determined that more time is needed for substitutes to be designed,
tested, qualified, validated, and deployed.
Comment: Three commenters said that an extension to January 1,
2030, may still be insufficient. Two of these commenters suggested that
it may be insufficient for applications between -50 [deg]C and -30
[deg]C. The other commenter recommended an extension until December 31,
2030, to provide regulatory predictability and flexibility noting that
the proposed timeline to transition may be too short. This commenter
also supported an exemption for this equipment, noting that transition
challenges will likely continue to persist past 2030. One commenter
noted that even where substitutes may eventually become viable,
equipment redesign, testing and qualification processes typically take
at least five years from concept to deployment.
Response: The EPA acknowledges that qualification cycles for
process refrigeration equipment in the semiconductor manufacturing
industry can take a long time. The EPA notes that the submitter of the
administrative petition indicated January 1, 2030, as a realistic
compliance deadline, and that five semiconductor equipment
manufacturers submitted letters in support of the petition. At this
time, the EPA does not have any technical information or data that
justifies a date other than what the Agency proposed. To the extent
additional information is provided that January 1, 2030, may not be
sufficient, the EPA will consider revising the compliance date.
Comment: One commenter suggested that the EPA should provide a
mechanism to re-evaluate the compliance date in 2028 for very low
temperature applications.
Response: The EPA appreciates this comment, but the Agency did not
propose and is not finalizing a mechanism to re-evaluate the 2030
compliance date. The Agency will continue to monitor the transition and
encourages regulated entities to continue to share information on the
development and deployment of alternative refrigerants, including those
for low temperature applications. Based on the information and data the
EPA currently has, the Agency anticipates this sector will be able to
meet the January 1, 2030, compliance date as it will continue its
progress on equipment

[[Page 31303]]

redesign, testing, and qualification processes.
Comment: One commenter suggested the EPA establish a formal supply
chain readiness review in advance of the 2030 deadline.
Response: The EPA did not propose and is not finalizing a formal
mechanism to evaluate supply chain readiness in advance of 2030. The
Agency will continue to monitor supply chain readiness. Based on the
information the EPA currently has, the Agency does not foresee any
supply challenges with meeting a 2030 deadline. However, if that
changes, the EPA will reevaluate whether the 2030 deadline is
achievable.
Comment: Commenters requested that the EPA narrow or expand the
scope of equipment subject to this provision. One commenter encouraged
the EPA to be clear that this flexibility applies to a narrow subset of
equipment that requires extreme-precision projection lenses (e.g.,
lithography), and not to other chillers and refrigeration systems used
in fabrication plants. One commenter suggested that the EPA consider
extending the proposal to all industrial process chillers with charge
sizes up to 100 pounds, not just those used in SMRE. They stated that a
uniform compliance date for these equipment types would be easier for
manufacturers and users to administer, given the practical difficulty
of identifying end-use applications.
Response: The EPA reaffirms that it is finalizing an extension only
for a narrow subset of process refrigeration equipment that requires
extreme precision used in the manufacture of semiconductors. Based on
the information provided to the EPA, these process chillers and IPR
equipment are highly specialized and require time to be qualified,
validated, and deployed for use in semiconductor manufacturing. The EPA
does not have sufficient technical information and does not consider it
necessary to further narrow this provision to a specific subset(s) of
semiconductor manufacturing equipment, such as projection lenses. The
EPA finds that a delineation of SMRE with a charge size of 100 pounds
or less is appropriate given the shared challenges of this equipment to
be qualified, validated, and deployed for use.
The EPA did not propose and is not finalizing an exemption for all
IPR and Chillers for IPR equipment with a charge size of 100 pounds or
less except where such equipment is used for semiconductor
manufacturing. The EPA acknowledges that IPR and Chillers for IPR are
used in a range of applications. The EPA understands from the
petitioner and from supporting information that semiconductor
manufacturing use of IPR and Chillers for IPR equipment have unique
challenges.
As described in this section IV.B, section III.B of this preamble,
and in the October 2025 Proposal, the Agency received and considered
new information after the issuance of the 2023 Final Rule specifically
about semiconductor manufacturing. The Agency did not receive
information concerning the limit or compliance for IPR and Chillers for
IPR equipment containing 100 pounds or less more generally. Further,
the EPA does not have information that would support the conclusion
that it would be impossible to differentiate semiconductor
manufacturers from other users of IPR or Chillers for IPR equipment.
Comment: Two commenters supported the EPA's clarification in the
proposal that ``the lowest temperature at which equipment is designed
to operate determines whether it is subject to use restrictions.''
Response: The EPA acknowledges these commenters' support. The EPA
reiterates that IPR and Chillers for IPR used in the semiconductor
manufacturing industry may operate at one temperature while being
designed to reach lower temperatures. As stated in section III.A of
this preamble, the lowest temperature at which equipment is designed to
operate determines whether it is subject to use restrictions.

C. Retail Food--Supermarkets

1. Graduated Schedule
Comment: Some commenters supported the proposed graduated schedule
to provide time for manufacturers and contractors to adapt, train
technicians, develop safety protocols, and update building codes. One
commenter also claimed that the original transition dates would
disproportionately affect independent grocers, who would bear
additional costs and pass them on to consumers. Another commenter
stated that the phased approach benefits small and/or rural
supermarkets with reasonable capital planning, coordinated vendor
engagement, and long-term equipment investment, all of which provide
critical flexibility for independent grocers.
Another commenter supported the limit of 1,400 for retail food
applications to allow industry to organically transition to A2L
refrigerants. According to one commenter, industry experts estimate
that a minimum of 2-3 years is required after code updates before safe
implementation can begin. Another commenter stated that the extended
compliance date to 2032 allows code officials to put the appropriate
Life Safety codes in place before introducing lower flammability
refrigerants. One commenter agreed that supermarket systems required a
later start date compared to remote condensing units in the phase-in
approach, given they are more complex. The commenter also stated that
the revisions to the compliance schedule provide immediate relief for
stores needing to install new systems while providing a workable
pathway to the 2023 Technology Transition Rule's targets.
Response: The EPA acknowledges commenters' support for the proposed
graduated schedule of limits for supermarket systems. The Agency
understands the need for additional flexibility for supermarket systems
in the near term, and acknowledges the complexity involved with
designing and installing such systems and potential challenges with
building code adoption, particularly at the local level. The EPA
understands that many factors may be considered by store owners and
operators when selecting a supermarket system, including choice of
refrigerant. The EPA assessed the additional flexibility of providing
the interim limit of 1,400 beginning on January 1, 2027, as adding for
an additional set of refrigerants to be available for such
consideration and aligns with the comments the EPA received. Commenters
pointed to the need for more flexibility when selecting a refrigerant
for their supermarket systems as well as allowing additional time for
wider adoption of building codes to allow even more options, including
A2L refrigerants.
Delaying the compliance date to 2032 for the limit of 150 or 300,
as applicable, provides an additional five years for retailers to
continue to install systems using HFC refrigerants below the 1,400
limit, which provides sufficient time for any current concerns
identified by commenters to be resolved. The EPA is aware that there
are already available options in use for supermarket systems that meet
the requirements in the 2023 Final Rule; however, based on the
information received ahead of the proposed changes and during the
comment period, the EPA concludes that there are challenges related to
deploying such systems in certain geographical areas of the United
States that result in lag which is addressed by this rule. The Agency
describes and responds to these comments and concerns, including
building codes,

[[Page 31304]]

energy efficiency, and more, in later responses in this section and in
the Response to Comments found in the docket for this rule.
Comment: Some commenters opposed the sector-wide delay and interim
limit for supermarket systems and stated that the requirements
established in the 2023 Final Rule should be maintained. One commenter
stated that weakening the rules for retail food systems will confuse
the market, penalize early adopters, reward laggards, and lock in more
environmentally harmful refrigerants for decades to come. Another
commenter stated that California state regulations adopted a 150 limit
for commercial and industrial refrigeration that have been enforced
since 2022. They noted that through extensive stakeholder outreach, the
retail food industry expressed desire to have future-proof solutions
rather than interim solutions that would be more costly.
One commenter stated that EPA proposed these delays and increases
in limits without having necessary information available, as evidenced
by the Agency seeking multiple types of information in the proposed
rule, and thus the proposed timelines and limits are not supported by
technical information. One commenter stated that maintaining the
previous compliance schedule preserves the United States as an early
mover promoting American innovation and technology.
Delays in the compliance schedule would re-open the domestic market
to outdated technologies and give foreign manufacturers a competitive
advantage. Another commenter stated that delaying implementation until
2032 would negate potential reductions in emissions of refrigerants,
and the delay goes against the AIM Act's requirement for a rapid
transition to alternatives.
Response: The EPA disagrees with the commenters' opposition to the
proposal and generally disagrees with these comments related to
retaining the limits and compliance dates for supermarket systems. The
EPA is finalizing a graduated schedule approach which retains as a
first step the January 1, 2027, compliance date, consistent with the
compliance date in the 2023 Final Rule for supermarket systems. The
Agency reiterates that it is aware that some retailers are able to use
refrigerants below the limits set in the 2023 Final Rule already;
however, the Agency concludes for reasons stated elsewhere in this
section, there are supermarkets that will benefit from the flexibility
the EPA is creating by moving to the graduated schedule. While the
interim limit is in effect from January 1, 2027, until January 1, 2032,
store owner and operators would have options for refrigerants that are
above the 150 and 300 limits and below the 1,400 limit, including but
not limited to R-448A, R-449A, and R-513A.<SUP>116 117</SUP> R-448A, R-
449A, and R-513A are classified under ASHRAE as A1 refrigerants,
meaning they are non-flammable and do not have the same installation
challenges as refrigerants with A2, A2L, and A3 flammability
characteristics.\118\ Thus, this offers retailers the opportunity to
use a refrigerant with similar flammability and pressure ratings to
what the industry may have historically used. However, the EPA notes
that there will be other reasons for retailers to move to refrigerants
with 150 or 300 limits ahead of 2032.
---------------------------------------------------------------------------

\116\ R-448A is a blend of three HFCs and two HFOs. R-449A is a
blend of three HFCs and one HFO. R-513A is a blend of one HFC and
one HFO.
\117\ See trade association's letter to the EPA, dated February
11, 2025, in the docket for this action, and GreenChill
``Partnership Accomplishments'' at <a href="https://www.epa.gov/greenchill/partnership-accomplishments">https://www.epa.gov/greenchill/partnership-accomplishments</a>.
\118\ ANSI/ASHRAE Standard 34-2024 Designation and Safety
Classification of Refrigerants.
---------------------------------------------------------------------------

For example, the HFC phasedown and particularly the 2029 HFC
reduction step could impact price and availability of R-448A, R-449A,
R-513A, and other HFC or HFC refrigerant blends. There will also be
time for the supermarket industry to become more familiar with
CO<INF>2</INF> systems. Therefore, some retailers may choose to use a
substitute that is below 150 or 300, as applicable, prior to the
compliance date of January 1, 2032. The EPA disagrees that finalizing
the graduated schedule would go against the goals of the AIM Act for a
rapid transition to alternatives. While subsection (e) of the AIM Act
establishes the HFC phasedown schedule, the AIM Act does not prescribe
a defined schedule for the transition to alternatives for any specific
sectors and subsectors.
The EPA understands that a delay in the compliance date for the
limits of 150 or 300, as applicable, could result in additional use of
HFCs in this subsector; however, the EPA does not agree that this would
have a significant impact on the continued use of legacy HFC systems.
The interim limit of 1,400 beginning on January 1, 2027, means that
legacy HFC refrigerant blends, such as R-404A, R-407A, and R-507A,
would not be installed in new supermarket systems starting January 1,
2027, and instead only those that meet the interim limit could be used.
The EPA considers the 2027 interim limit to be significant, and it is
important that it occurs ahead of the 2029 phasedown step. Further, the
EPA disagrees that the graduated schedule approach finalized in this
rulemaking would discourage American innovation and reward foreign
entities.
By providing the interim limit for five years, the EPA is providing
additional time for U.S. companies to further develop, design, and
distribute technologies for supermarket systems that use refrigerants
below the 2032 limits that meet the needs of particular stores.
Retailers also still have the option to adopt technologies that use
refrigerants below the 150 or 300 limit sooner than the 2032 compliance
date in this rule.
Comment: Some commenters suggested alternate compliance dates or
limits compared to the proposal for supermarket systems. Commenters
requested the limit align with the next stepdown date of the allocation
phasedown schedule and should be adjusted to 2029 for supermarket
systems. One commenter stated that instituting the interim limit of
1,400 followed by a limit of 150 or 300, as applicable, beginning in
2029 would still allow flexibility in the near term and would
accelerate retrofits or replacements to available substitutes. Another
commenter stated that a shorter extension to 2029 would avoid possible
long-term cost increases for regulated refrigerants.
Some commenters opposed the proposed delays and interim limits but
said if the EPA were to finalize a delayed compliance date for the
limits of 150 or 300, as applicable, it should be no later than January
1, 2029. One commenter stated that a two-year extension would be needed
for supermarket systems due to constraints on the use of A2L
refrigerants that meet the limits of 150 or 300, as applicable.
Response: The EPA disagrees with these commenters' assertion that
EPA must or should align the 150 or 300 limit, as applicable, with the
2029 phasedown step. As a general matter, the EPA does not agree that
compliance dates established under the Technology Transitions
subsection of the AIM Act need to align with the dates Congress
established for the phasedown schedule under AIM Act subsection (e).
These are two distinct subsections, each with their own direction and
authority. The EPA concludes that only providing an additional two
years would provide limited flexibility to retailers and would not be
sufficient. As described elsewhere in comment responses in this
section, the interim limit and delay in the final limit for the
subsector, as finalized, provide sufficient flexibility in refrigerant
choice and time for industry nationwide to fully prepare

[[Page 31305]]

with the 150 or 300 limits, as applicable. For example, the additional
five years will allow OEMs more time to develop equipment meeting the
needs of all their customers and to establish supply chains to
distribute such equipment throughout the United States.
Comment: Commenters stated that the proposed delay in compliance
dates for supermarket systems would conflict with the AIM Act's
requirement for phasing down production of HFCs, and there will be a
much greater demand for HFCs by 2032 than allowed production can
support. One commenter stated that delays in the compliance dates and
limits would continue to elevate demand for new systems as the
phasedown gets tighter, which would draw down HFC inventories and push
demand above supply by 2030. One commenter stated that the delays to
the requirements would increase near-term HFC demand and misalign the
AIM Act's intended ability to guide an orderly transition. Another
commenter expressed concern that extending use of legacy refrigerants
in the retail food sectors will significantly add to demand, draw down
existing stocks of HFCs, and shift the allowance pool away from HFCs
that meet lower limits towards unnecessary legacy refrigerants.
Another commenter stated that raising the limit for refrigerants in
commercial refrigeration systems would increase HFC consumption, given
high average leak rates in this sector, and would contradict the
overall phasedown of HFCs under the AIM Act. One commenter stated that
an extension to 2029 for supermarket systems would not materially
impact a potential shortage of HFCs in 2029, while delaying to 2032
could have such adverse effects and since supermarkets would have a
longer period of time to use legacy HFC systems.
Some commenters noted that the delays and increased demand will
cause prices to increase for HFCs in the retail food sector. One
commenter expressed warning that the delays may come with broader
negative impacts to the entire consumer base in the near term,
including refrigerant shortages as soon as 2028. Another commenter
stated the increased costs for maintenance and refrigerants in the
retail food sector would be passed on to American consumers. Another
commenter stated that any shortfall between available supply and
required servicing demand is likely to cause higher prices for all end
users.
One commenter anticipates that a refrigerant shortage may occur
starting in 2027 if compliance dates and limits are relaxed. They
commented that such delays and relaxed limits will further cause
shortages beyond the commercial refrigeration sector and would affect
other sectors such as residential and commercial air conditioning,
leading to increased servicing costs for consumers.
Response: The EPA disagrees with commenters that assert that
delaying the 2023 Final Rule limits of 150 or 300, as applicable, for
supermarket systems by an additional five years would adversely affect
the overall phasedown of HFCs under the AIM Act. As noted previously,
the phasedown schedule Congress established in subsection (e) of the
AIM Act is wholly separate from the Technology Transitions provisions
in subsection (i). The EPA acknowledges that continued installation of
new HFC supermarket systems inherently results in future demand for
HFCs to service such systems.
The EPA disagrees that it is necessary or appropriate to choose
compliance dates under subsection (i) based on the phasedown schedule
that align the limits for supermarket systems with the next phasedown
step are a hook upon which to establish a date. Congress' direction
under subsection (i) is to the extent practicable, factor in ``the
remaining phase-down period for regulated substances,'' among other
factors. In addition, the phasedown itself is a separate and key market
driver for all refrigerant users. The EPA has considered the remaining
phasedown period as well as the other factors listed in subsection
(i)(4) and factored them in to the extent practicable, consistent with
Congressional direction.
Comment: One commenter suggested adjusting the interim limits to
750 rather than 1,400 and reduce to 150 or 300 in 2032. The commenter
stated this aligns more closely with currently available technology.
Response: The EPA disagrees that an interim limit of 750 would be
appropriate for the supermarket systems subsector. The EPA acknowledges
that to a large extent, in the 2023 Final Rule, the Agency used a few
numerical limits, such as 150 or 700. However, the EPA did not use 750
in any sector or subsector and, moreover, it made its decisions based
on information relevant specifically to each sector or subsector. As
described in other comment responses in this section, two HFC
refrigerant blends (i.e., R-448A and R-449A) are currently being used
in new supermarket system installations and are below the 1,400 limit;
however, these substitutes are above a limit of 750. While R-513A was
also mentioned as a refrigerant option for this subsector and could
meet a 750 limit, such a limit would not allow R-448A or R-449A and
would limit the flexibility in refrigerant choice for supermarket
systems during the interim period.
Comment: Commenters stated that there are substitutes and
technologies available for supermarket systems. One commenter noted
that the record does not support claims that substitutes are not
available, or the building codes require sector-wide delays. One
commenter stated that many distributors report that complete
supermarket refrigeration solutions that meet the 150 or 300 limit are
on the market and used in the installation of supermarket systems in
various regions across the country, including the southern United
States. Other commenters stated that there are multiple Significant New
Alternatives Policy (SNAP) listings for available substitutes for
supermarket systems with safety standards incorporating Underwriters
Laboratories (UL) 60335-2-89 and ASHRAE 15-2022.
Response: As stated previously, the EPA understands that there are
challenges with transitioning to substitutes and technologies in
certain cases even if there are substitutes available for supermarket
systems that may be able to comply with the 2023 Final Rule compliance
timelines and limits. The EPA indicated in the 2023 Final Rule that
several substitutes, including CO<INF>2</INF> and some A1 and A2L HFC
blends, were available or would soon be available in time for the
supermarket systems subsector compliance date of 2027.\119\ The EPA
finalized SNAP Rule 26 and listed seven A2L substitutes as acceptable,
subject to use conditions, for use in new supermarket systems.\120\ Two
are non-HFC refrigerants (HFO-1234yf and HFO-1234ze(E)) and thus are
not subject to subsection (i) rules. Five are HFC/HFO blends (R-457A,
R-516A, R-454C, R-455A, and R-454A), which, except for R-454A, satisfy
the 150 limit for installation in new supermarket systems that have a
charge size of 200 pounds or more. All of these refrigerants may also
be installed in such systems that have a charge size less than 200
pounds, or as part of the high temperature side of a cascade system.
---------------------------------------------------------------------------

\119\ See 88 FR 73098 (October 24, 2023).
\120\ See 89 FR 50410 (June 13, 2024).
---------------------------------------------------------------------------

While increasing the number of refrigerants listed as acceptable
under the SNAP program can provide more options, more time is needed
for chemical suppliers to provide them in sufficient quantities, for
equipment manufacturers to develop equipment for these substitutes, and
for this equipment

[[Page 31306]]

to be incorporated into new supermarket system designs and be deployed.
The EPA is seeking to avoid supply chain issues similar to those that
arose with the deployment of the new refrigerant blend, R-454B, in the
residential and light commercial AC/HP subsector. In that situation,
while the refrigerant was being manufactured in sufficient quantities,
it was not available in field for equipment installation and
servicing.\121\
---------------------------------------------------------------------------

\121\ See Memorandum--Overview of R-454B Refrigerant Shortage
and Current Status, in the docket for this action.
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Extending the compliance date for this subsector to 2032 for the
limits of 150 or 300, as applicable, preserves optionality and
flexibility in the interim period and allows market pressure and the
advantages of the new refrigerants to drive the continued transition to
identified substitutes as the commercial availability of newer
substitutes matures. The EPA thus expects that refrigerant options
below the 150 or 300 limits, as applicable, including those identified
as available substitutes for supermarket systems in the 2023 Final Rule
and those listed in SNAP Rule 26 for this subsector, will become more
widely available for this subsector by January 1, 2032.
Comment: One commenter stated that the EPA contradicted itself in
asserting that there are too few refrigerants available that meet the
150 or 300 limit since the EPA already stated there are available
substitutes in the 2023 Final Rule. The commenter further stated that
any one of the available substitutes identified by the EPA would be
enough to support the existing rule (i.e., the 2023 Final Rule).
Another commenter further stated that the EPA's request for more
information on alternatives was unnecessary because availability of
substitutes was already demonstrated in the 2023 Final Rule, and the
use of alternatives continues to grow. One commenter stated that the
statutory test for availability of alternatives is when one is
available, and there is no requirement for an arbitrary number of
multiple substitutes to be available.
Response: As described in the prior comment response, the EPA
agrees that there are substitutes available for the supermarket systems
subsector. However, the EPA disagrees with the comment that there is a
statutory test indicating that the availability of a single substitute,
or a number of multiple substitutes, demands a particular outcome. The
availability of substitutes is one factor the EPA considers when
promulgating rulemaking under subsection (i) of the AIM Act. Subsection
(i) directs the EPA to factor in, to the extent practicable, more than
a half dozen considerations, some or all of which may be applicable for
a particular subsector or substitute. Furthermore, the breadth of end
uses in a subsector may require multiple substitutes, which the EPA may
consider to determine that substitutes are available in that subsector.
Comment: Commenters provided examples of substitutes, primarily
CO<INF>2,</INF> in use today in supermarket systems. One commenter
provided evidence that large and small retail food facilities
throughout California have been effectively using CO<INF>2</INF> and
other refrigerants that meet the 150 or 300 limit. Another commenter
provided multiple examples of large and small grocery stores and chains
that have made progress and commitments to transition to CO<INF>2</INF>
and refrigerants that meet the 150 or 300 limit in their stores. One
commenter stated that in their research, 2,800 retail food stores in
the United States have transitioned to equipment using CO<INF>2</INF>
as of the end of 2023. Some commenters stated that approximately 4,100
stores were using transcritical CO<INF>2</INF> systems as of December
2024. One commenter provided data on the numbers of stores by certain
companies that are already using CO<INF>2</INF> in supermarket systems,
including in larger and smaller format stores. Other commenters stated
that the use of CO<INF>2</INF> in supermarket systems increased by over
40-50 percent from 2023 to 2024. Another commenter stated that
CO<INF>2</INF> adoption in supermarket systems is projected to grow
from 5.8 percent of retail food stores today to 22 percent by 2028.
Another commenter stated that CO<INF>2</INF> systems are proven and
widely used by many retailers and that components such as compressors,
valves, controls, etc. are available from a diversified supply chain.
The commenter noted that there are technician training programs in
place nationwide to support adoption. One commenter stated that
CO<INF>2</INF> is already being used in supermarket systems, even in
warmer climates, and year-to-date manufacturing of equipment that meets
the 150 or 300 limit has increased dramatically. The commenter further
stated that they use multiple available substitutes for commercial
refrigeration categories in the proposal in their standard product
offerings, including R-454A, R-454C, R-455A, and CO<INF>2</INF>. They
commented that they provide a product line that is currently
manufactured and sold that meets the 150 or 300 limits, including
refrigerant rack systems.
Response: The EPA acknowledges the examples provided by commenters
of equipment that is currently available that meets the 150 or 300
limit, as applicable, for supermarket systems, and which aligns with
the EPA's understanding of available equipment described in the prior
comment response in this section. As stated previously, nothing in this
rule would prevent retailers from transitioning to a supermarket system
that would comply with the 150 or 300 limits. As commenters stated,
there are many such examples, and the EPA expects that there will be
retailers who might opt for such refrigerants prior to January 1, 2032,
if they are installing a new supermarket system. The EPA anticipates
that at least 20% of the market will transition to a supermarket system
below the limits of 150 or 300, as applicable, well before the
compliance date on January 1, 2032.\122\ The EPA is aware of several
major supermarket chains that have made announcements indicating such
transitions and thus the EPA assumes those companies will not take
advantage of the additional flexibility afforded by this final rule.
The EPA anticipates the additional time for compliance will allow these
systems to continue to be improved and have additional widespread
availability across the country.
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\122\ See Economic and Environmental Impacts Memo in the docket
for this action.
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As stated in prior responses, while there are supermarket systems
available with substitutes below the limit of 150 or 300, as
applicable, the graduated schedule in this rule is still necessary to
provide flexibility for choice of refrigerant until these limits are
effective in 2032. The availability of substitutes is just one factor
among many that the EPA considers for establishing the limits in the
supermarket systems subsector. Supermarket systems are not off-the-
shelf systems and are configured with many different components to meet
the specific needs of the store in which it will be used. The graduated
schedule considers this as some retailers may transition to these
available substitutes sooner than January 1, 2032, while others may
require additional flexibility.
Comment: Some commenters provided information on the potential
energy efficiency benefits of certain refrigerants in supermarket
systems. One commenter disagreed with the EPA's claims that installing
CO<INF>2</INF> in warmer climates may be less energy efficient; the
commenter provided an example of a grocer who announced

[[Page 31307]]

they would transition to CO<INF>2</INF> for all stores, including those
in warmer climates. One commenter also stated that CO<INF>2</INF>
systems can provide energy efficiency benefits, even in warmer
climates. One commenter stated that properly configured CO<INF>2</INF>
and A2L systems use similar or less energy compared to older HFC
technologies. Another commenter stated that A2L blends like R-454C
match capacity within 3-5 percent and improve energy efficiency as
compared to R-404A for supermarket systems.
Response: The EPA acknowledges that some store owners and operators
have experienced energy-efficiency benefits when installing supermarket
systems with newer refrigerants. Retailers may select supermarket
systems with a particular refrigerant for a number of reasons,
including the overall energy efficiency of the system. However,
retailers may also factor in other considerations such as capital and
operating costs, required maintenance of a system, availability of
technicians trained to use substitutes, and geographic location of the
store. New supermarket systems using CO<INF>2</INF> have been installed
at an increasing rate in recent years, and it is expected this trend
will continue. As the EPA understands, many installations of
CO<INF>2</INF> systems have been in colder climates, where existing
technology can provide energy efficiency benefits and overall lower
cost of ownership throughout the life of the system. There have been
installations in warmer climates as well; however, the EPA does not
have sufficient information that would allow the Agency to tie a
certain energy cost or savings to a certain climate. Further, retailers
who choose to install a supermarket system with CO<INF>2</INF> or an
A2L blend must also consider other factors such as available
technicians to install and service the system. It is likely that more
technicians are available in areas of the country where CO<INF>2</INF>
supermarket systems have already been deployed, potentially limiting
the availability of technicians on a regional basis at this time.
Delaying the compliance date for limits of 150 or 300 for
supermarket systems will allow sufficient time for CO<INF>2</INF>
technologies to be improved and made more efficient nationwide, as well
as provide time for more technicians to be trained and familiar with
these types of systems.
Comment: Commenters provided information and comments on the
challenges of availability and using substitutes for supermarket
systems. One commenter stated that many refrigerants below the 150 or
300 limit are either unavailable or withdrawn from the market and that
equipment manufacturers have not yet scaled to demand. One commenter
noted that they have experienced issues deploying A2L refrigeration
systems, as manufacturers currently only offer a handful of A2L systems
and most are small remote condensing units that are not suitable for
large grocery stores. Another commenter stated that A2L refrigerants
(e.g., R-454A, R-454C) remain prohibited under local building codes
that are more prohibitive than the state codes; and propane has a
charge size limit per circuit that requires dozens of self-contained
systems per supermarket, which is inefficient and space-intensive. One
commenter stated that even where A2L equipment is installed, many
installation companies are having issues with sourcing A2L refrigerants
in a reliable or timely manner. Conversely, another commenter stated
that HFOs, which are components in certain A2L refrigerant blends, are
ready to supply A2L refrigerants for use in supermarket systems;
however, supermarket systems (i.e., rack systems) using these
refrigerants may require more time for development and building codes
may need more time for these systems to use A2L refrigerants.
Other commenters stated that CO<INF>2</INF> systems pose numerous
challenges in warmer climates, and such systems are only efficient in
colder climates where they can be adequately cooled by ambient air. One
commenter stated that CO<INF>2</INF> systems are unreliable and only a
limited number of systems exist which require additional controls to
mitigate energy inefficiency. The commenter also pointed out that there
are additional safety and practical concerns with using alternatives,
including potential generation of hydrogen fluoride gas if an A2L
ignites, energy demand for CO<INF>2</INF> systems compared to HFC
systems, and a lack of trained technicians. One commenter stated that
there are only a handful of substitutes available for supermarket
systems, and each has certain challenges. They state that
CO<INF>2</INF> systems consume 20 percent more energy in southeastern
states, have higher capital costs, and there are a limited number of
qualified technicians available.
Response: The EPA acknowledges that there are currently available
substitutes for supermarket systems; however, the EPA has previously
indicated that challenges remain that could prevent transition in
accordance with the 2023 Final Rule. As stated previously in a comment
response in this section, the EPA also indicated in the 2023 Final Rule
that several substitutes, including CO<INF>2</INF> and some A1 and A2L
HFC blends were available or would be available in time for the
compliance date in that rule. Further, the EPA received comments
providing examples of stores currently using and planning to use
substitute refrigerants meeting the 150 or 300 limits, as applicable,
in their supermarket systems. While these substitutes are available,
the challenges with some substitutes that often are specific to regions
of the United States, may be related to availability of equipment,
installation and operation of equipment on a regional basis, design of
complex systems, availability of properly trained technicians, and
needed building code updates.
Providing an interim limit of 1,400 for five years will provide
additional flexibility and options of refrigerant choice when
installing a new supermarket system. The EPA understands that some
retailers may need this flexibility where the challenges may be too
cumbersome to use an available substitute that meets the 150 or 300
limit in 2027. As stated above in this section, the interim limit of
1,400 allows for certain common HFC blend refrigerants (e.g., R-448A,
R-449A, R-513A) in supermarket systems to be used in new installations
until the limits of 150 or 300, as applicable, take effect on January
1, 2032. Retailers have been using R-448A, R-449A, and R-513A in recent
years and technicians are familiar with and trained to work on
equipment using these refrigerants.
Delaying the compliance date for the 150 or 300 limits, as
applicable, for supermarket systems to January 1, 2032, provides
sufficient time for industry to prepare for these limits for new
installations of supermarket systems. The additional five years will
provide additional time for more technicians to be trained on
supermarket systems using compliant refrigerants. For example,
supermarket systems that use CO<INF>2</INF> as a refrigerant operate at
high pressures, and technicians will need to be trained to properly and
safely maintain these systems. As noted, many technicians across the
country may be qualified to service systems using refrigerants meeting
the 150 or 300 limits; however, they may be more regionally
concentrated in areas of the country where such supermarket systems
have had higher adoption rates over recent years. The EPA expects that
as more supermarket systems are installed across the country in all
regions that are compliant with the 150 or 300 limits, technicians will
likewise adapt and become qualified and trained to maintain these
systems.

[[Page 31308]]

The EPA also acknowledges that there may be certain challenges for
supermarket systems that use CO<INF>2</INF> based on where the store is
located regionally. Particularly, commenters noted that CO<INF>2</INF>
supermarket systems are less efficient in warmer climates where they
cannot take advantage of cooling from ambient conditions. The EPA
understands that current technologies may present such challenges;
however, as noted in a prior response, there have been installations of
CO<INF>2</INF> in warmer climates. Other comments submitted on the
proposed rule provided examples where CO<INF>2</INF> supermarket
systems have been installed across the country in various regions and
have proven to be at least as efficient as legacy HFC systems. Further,
other commenters noted commitments from retailers to continue with new
installations of CO<INF>2</INF> systems in new stores across the
country. Nonetheless, the EPA acknowledges that challenges and
opportunities may vary in independent cases, as supermarket systems are
large and complex. As such, delaying the compliance date for limits of
150 or 300 in supermarket systems will provide sufficient time for
innovation in supermarket systems using CO<INF>2</INF>. The EPA
anticipates that technologies will continue to improve and provide
equipment and designs that will operate efficiently in any region of
the country.
In addition to CO<INF>2</INF> as a choice of refrigerant in
supermarket systems, the EPA recognizes that there are additional
substitutes available that are classified as A2L. Commenters described
challenges with potential safety concerns and building code updates
preventing wide-scale adoption of supermarket systems with A2L
refrigerants. Regarding the toxicity of breakdown products such as
hydrogen fluoride, the EPA's SNAP program considers potential impacts
of breakdown products, including hydrogen fluoride upon combustion. The
EPA also notes that HFCs mixed with compressor oil also can be
flammable at high enough temperatures, and thus, generation of hydrogen
fluoride is not unique to A2L refrigerants. The EPA discusses comments
related to building codes and provides a more detailed response later
in this section. Building code updates are rapidly occurring and
underway in nearly all states with processes in place to use A2Ls where
codes have not been fully updated. While this is the case, there may be
challenges or time-consuming approval processes for installations of
supermarket systems with large charge sizes in some jurisdictions.
Thus, delaying the compliance dates for limits of 150 or 300 in
supermarket systems would allow additional time for more uniform
adoption of updated building codes across the country, including in
local jurisdictions.
Comment: One commenter stated that the initial start-up costs of
CO<INF>2</INF> systems have dropped considerably in the last five
years. Another commenter also stated that CO<INF>2</INF> technologies
have advanced significantly in recent years, resulting in lower
sustained costs as initial costs decrease with increased adoption. The
commenter also stated that A2L systems have already been developed for
the 2026 and 2027 compliance dates, and they are expected to be
comparable in cost to HFC systems. Another commenter stated that ultra-
low GWP refrigerants provide cost savings, including reduced operating
costs through greater energy efficiency.
Response: The EPA appreciates comments provided on the costs of
supermarket systems installed with substitute refrigerants. The EPA
agrees that with increased adoption of such systems, initial costs
would be expected to decrease, although the rate and amount of the
decrease in costs is uncertain and the EPA has not assumed declining
capital or operating costs over time for purposes of the Economic and
Environmental Impacts Memo. The EPA also acknowledges that in some
cases, there may be energy efficiency benefits with supermarkets
systems using certain refrigerants. The EPA further discusses these
considerations in other responses in this section.
Comment: Some commenters stated that CO<INF>2</INF> systems carry
higher operating costs than HFC refrigerants due to complexity,
inefficiency, and higher leak rates. Another commenter stated that the
current compliance schedules would result in exorbitant compliance
costs as a result of the barriers for HFC alternative refrigerants and
technologies, including higher ca

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