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Proposed Rule2023-09600

Protection of Stratospheric Ozone: Listing of Substitutes Under the Significant New Alternatives Policy Program in Commercial and Industrial Refrigeration

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Published

May 24, 2023

Issuing agencies

Environmental Protection Agency

Abstract

Pursuant to the U.S. Environmental Protection Agency's Significant New Alternatives Policy program, this action proposes to list certain substances in the refrigeration and air conditioning sector. Specifically, EPA proposes to list several substitutes as acceptable, subject to use conditions, for retail food refrigeration, commercial ice machines, industrial process refrigeration, cold storage warehouses, and ice skating rinks. Through this action, EPA is proposing to incorporate by reference standards which establish requirements for commercial refrigerating appliances and commercial ice machines, safe use of flammable refrigerants, and safe design, construction, installation, and operation of refrigeration systems. This action also proposes to exempt propane, in the refrigerated food processing and dispensing end-use, from the prohibition under the Clean Air Act (CAA) on knowingly venting, releasing, or disposing of substitute refrigerants, on the basis of current evidence that the venting, release, or disposal of this substance in this end-use does not pose a threat to the environment.

Full Text

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<title>Federal Register, Volume 88 Issue 100 (Wednesday, May 24, 2023)</title>
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[Federal Register Volume 88, Number 100 (Wednesday, May 24, 2023)]
[Proposed Rules]
[Pages 33722-33797]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2023-09600]

[[Page 33721]]

Vol. 88

Wednesday,

No. 100

May 24, 2023

Part III

Environmental Protection Agency

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40 CFR Part 82

Protection of Stratospheric Ozone: Listing of Substitutes Under the
Significant New Alternatives Policy Program in Commercial and
Industrial Refrigeration; Proposed Rule

Federal Register / Vol. 88 , No. 100 / Wednesday, May 24, 2023 /
Proposed Rules

[[Page 33722]]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 82

[EPA-HQ-OAR-2023-0043; FRL-10125-1-OAR]
RIN 2060-AV77

Protection of Stratospheric Ozone: Listing of Substitutes Under
the Significant New Alternatives Policy Program in Commercial and
Industrial Refrigeration

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice of proposed rulemaking.

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SUMMARY: Pursuant to the U.S. Environmental Protection Agency's
Significant New Alternatives Policy program, this action proposes to
list certain substances in the refrigeration and air conditioning
sector. Specifically, EPA proposes to list several substitutes as
acceptable, subject to use conditions, for retail food refrigeration,
commercial ice machines, industrial process refrigeration, cold storage
warehouses, and ice skating rinks. Through this action, EPA is
proposing to incorporate by reference standards which establish
requirements for commercial refrigerating appliances and commercial ice
machines, safe use of flammable refrigerants, and safe design,
construction, installation, and operation of refrigeration systems.
This action also proposes to exempt propane, in the refrigerated food
processing and dispensing end-use, from the prohibition under the Clean
Air Act (CAA) on knowingly venting, releasing, or disposing of
substitute refrigerants, on the basis of current evidence that the
venting, release, or disposal of this substance in this end-use does
not pose a threat to the environment.

DATES: Comments must be received on or before July 10, 2023. Any party
requesting a public hearing must notify the contact listed under FOR
FURTHER INFORMATION CONTACT by 5 p.m. Eastern Daylight Time on May 30,
2023. If a virtual public hearing is held, it will take place on or
before June 8, 2023, and further information will be provided on EPA's
Stratospheric Ozone website at <a href="https://www.epa.gov/snap">https://www.epa.gov/snap</a>.

ADDRESSES: You may send comments, identified by Docket ID No. EPA-HQ-
OAR-2023-0043, by any of the following methods:
<bullet> Federal eRulemaking Portal: <a href="https://www.regulations.gov/">https://www.regulations.gov/</a>
(our preferred method). Follow the online instructions for submitting
comments.
<bullet> Mail: U.S. Environmental Protection Agency, EPA Docket
Center, Air and Radiation Docket, Mail Code 28221T, 1200 Pennsylvania
Avenue NW, Washington, DC 20460.
<bullet> Hand Delivery or Courier: EPA Docket Center, WJC West
Building, Room 3334, 1301 Constitution Avenue NW, Washington, DC 20004.
The Docket Center's hours of operations are 8:30 a.m.-4:30 p.m.,
Monday-Friday (except Federal Holidays).
Instructions: All submissions received must include the Docket ID
No. for this rulemaking. Comments received may be posted without change
to <a href="https://www.regulations.gov/">https://www.regulations.gov/</a>, including any personal information
provided. For additional information on the rulemaking process, see the
SUPPLEMENTARY INFORMATION section of this document.
All documents in the docket are listed on the <a href="https://www.regulations.gov">https://www.regulations.gov</a> website. Although listed in the index, some
information is not publicly available, e.g., Confidential Business
Information (CBI) or other information whose disclosure is restricted
by statute. Certain other material, such as copyrighted material, is
not placed on the internet and will be publicly available only in hard
copy form. Publicly available docket materials are available
electronically through <a href="https://www.regulations.gov">https://www.regulations.gov</a> or in hard copy at
the Air and Radiation Docket at the address above. For further
information on EPA Docket Center services and the current status,
please visit <a href="https://www.epa.gov/dockets">https://www.epa.gov/dockets</a>.

FOR FURTHER INFORMATION CONTACT: Gerald Wozniak, Stratospheric
Protection Division, Office of Atmospheric Protection (Mail Code
6205A), Environmental Protection Agency, 1200 Pennsylvania Ave. NW,
Washington, DC 20460; telephone number: 202-343-9624; email address:
<a href="/cdn-cgi/l/email-protection#0e79617460676f6520696b7c6f626a4e6b7e6f20696178">[email&#160;protected]</a>. Notices and rulemakings under EPA's Significant
New Alternatives Policy (SNAP) program are available on EPA's SNAP
website at <a href="https://www.epa.gov/snap/snap-regulations">https://www.epa.gov/snap/snap-regulations</a>.

SUPPLEMENTARY INFORMATION:

Table of Contents

I. General Information
A. Executive Summary and Background
B. Does this action apply to me?
C. What acronyms and abbreviations are used in the preamble?
II. What is EPA proposing in this action?
A. Retail Food Refrigeration--Proposed Listing of HFO-1234yf,
HFO-1234ze(E), R-454C, R-455A, R-457A, and R-516A as Acceptable,
Subject to Use Conditions, for Use in New Stand-Alone Units, Remote
Condensing Units, Supermarket Systems and Refrigerated Food
Processing and Dispensing Equipment and Proposed Listing of R-454A
as Acceptable, Subject to Use Conditions, for Use in Remote
Condensing Units and Supermarket Systems
1. Background on Retail Food Refrigeration
2. What are the ASHRAE classifications for refrigerant
flammability?
3. What are HFO-1234yf, HFO-1234ze(E), R-454A, R-454C, R-455A,
R-457A, and R-516A and how do they compare to other refrigerants in
the same end-use?
4. Why is EPA proposing these specific use conditions?
5. What additional information is EPA including in these
proposed listings?
6. On which topics is EPA specifically requesting comment?
B. Retail Food Refrigeration--Proposed Listing of R-290 as
Acceptable, Subject to Use Conditions, for Use in New Refrigerated
Food Processing and Dispensing Equipment and Proposed Revision of
the Use Conditions in the Previous Listings of R-290 as Acceptable,
Subject to Use Conditions, for Use in New Stand-Alone Units
1. Background on Retail Food Refrigeration
2. What are the ASHRAE classifications for refrigerant
flammability?
3. What is R-290 and how does it compare to other refrigerants
in the refrigerated food processing and dispensing equipment end-use
category?
4. Why is EPA proposing these specific use conditions for
refrigerated food processing and dispensing equipment?
5. How would the proposed listing for R-290 in refrigerated food
processing and dispensing equipment relate to regulations
implementing the venting prohibition under CAA section 608?
6. What use conditions currently apply to this refrigerant in
the stand-alone units end-use category?
7. What updates to existing use conditions for stand-alone units
is EPA proposing?
8. How do the proposed use conditions for stand-alone units
differ from the existing ones and why is EPA proposing to change the
use conditions?
9. What additional information is EPA including in these
proposed listings?
10. On which topics is EPA specifically requesting comment?
C. Commercial Ice Machines--Proposed Listing of HFC-32, HFO-
1234yf, R-454A, R-454B, R-454C, R-455A, R-457A, and R-516A as
Acceptable, Subject to Use Conditions, for Use in New Commercial Ice
Machines
1. Background on Commercial Ice Machines
2. What are the ASHRAE classifications for refrigerant
flammability?
3. What are HFC-32, HFO-1234yf, R-454A, R-454B, R-454C, R-455A,
R-457A, and R-516A and how do they compare to other refrigerants in
the same end-use?
4. Why is EPA proposing these specific use conditions?
5. What additional information is EPA including in these
proposed listings?

[[Page 33723]]

6. On which topics is EPA specifically requesting comment?
D. Commercial Ice Machines--Proposed Revision of the Use
Conditions in the Previous Listing of R-290 as Acceptable, Subject
to Use Conditions, for Use in New Self-Contained Commercial Ice
Machines
1. Background on Commercial Ice Machines
2. What are the ASHRAE classifications for refrigerant
flammability?
3. What is R-290 and where is there information on its use in
this end-use?
4. What use conditions currently apply to this refrigerant in
this end-use?
5. What updates to existing use conditions for commercial ice
machines is EPA proposing?
6. How do the proposed use conditions for commercial ice
machines differ from the existing ones and why is EPA proposing to
change the use conditions?
7. What additional information is EPA including in this proposed
listing?
8. On which topics is EPA specifically requesting comment?
E. Industrial Process Refrigeration--Proposed Listing of HFC-32,
HFO-1234yf, HFO-1234ze(E), R-454A, R-454B, R-454C, R-455A, R-457A,
and R-516A as Acceptable, Subject to Use Conditions, for Use in New
Industrial Process Refrigeration
1. Background on Idustrial Process Refrigeration
2. What are the ASHRAE classifications for refrigerant
flammability?
3. What are HFC-32, HFO-1234yf, HFO-1234ze(E), R-454A, R-454B,
R-454C, R-455A, R-457A, and R-516A and how do they compare to other
refrigerants in the same end-use?
4. Why is EPA proposing these specific use conditions?
5. What additional information is EPA including in these
proposed listings?
6. On which topics is EPA specifically requesting comment?
F. Cold Storage Warehouses--Proposed Listing of HFO-1234yf, HFO-
1234ze(E), R-454A, R-454C, R-455A, R-457A, and R-516A as Acceptable,
Subject to Use Conditions, for Use in New Cold Storage Warehouses
1. Background on Cold Storage Warehouses
2. What are the ASHRAE classifications for refrigerant
flammability?
3. What are HFO-1234yf, HFO-1234ze(E), R-454A, R-454C, R-455A,
R-457A, and R-516A and how do they compare to other refrigerants in
the same end-use?
4. Why is EPA proposing these specific use conditions?
5. What additional information is EPA including in these
proposed listings?
6. On which topics is EPA specifically requesting comment?
G. Ice Skating Rinks--Proposed Listing of HFO-1234yf, HFO-
1234ze(E), R-454C, R-455A, R-457A, and R-516A as Acceptable, Subject
to Use Conditions, for Use in New Ice Skating Rinks With a Remote
Compressor
1. Background on Ice Skating Rinks
2. What are the ASHRAE classifications for refrigerant
flammability?
3. What are HFO-1234yf, HFO-1234ze(E), R-454C, R-455A, R-457A,
and R-516A and how do they compare to other refrigerants in the same
end-use?
4. Why is EPA proposing these specific use conditions?
5. What additional information is EPA including in these
proposed listings?
6. On which topics is EPA specifically requesting comment?
H. Use Conditions and Further Information for Retail Food
Refrigeration, Commercial Ice Machines, Industrial Process
Refrigeration, Cold Storage Warehouses, and Ice Skating Rinks With a
Remote Compressor
1. What use conditions is EPA proposing and why?
2. What additional information is EPA including in these
proposed listings?
3. On which topics is EPA specifically requesting comment?
I. Proposed Exemption for R-290 From the Venting Prohibition
Under CAA Section 608 for Refrigerated Food Processing and
Dispensing Equipment
1. What is EPA's proposed determination regarding whether
venting, releasing, or disposing of R-290 in refrigerated food
processing and dispensing equipment would pose a threat to the
environment?
2. What is EPA's proposal regarding whether venting of R-290
from refrigerated food processing and dispensing equipment should be
exempted from the venting prohibition under CAA section 608(c)(2)?
3. When would the exemption from the venting prohibition apply?
4. What is the relationship between this proposed exemption
under CAA section 608(c)(2) and other EPA rules?
5. On which topics is EPA specifically requesting comment?
III. Statutory and Executive Order Reviews
A. Executive Order 12866: Regulatory Planning and Review and
Executive Order 13563: Improving Regulation and Regulatory Review
B. Paperwork Reduction Act (PRA)
C. Regulatory Flexibility Act (RFA)
D. Unfunded Mandates Reform Act (UMRA)
E. Executive Order 13132: Federalism
F. Executive Order 13175: Consultation and Coordination With
Indian Tribal Governments
G. Executive Order 13045: Protection of Children From
Environmental Health and Safety Risks
H. Executive Order 13211: Actions That Significantly Affect
Energy Supply, Distribution, or Use
I. National Technology Transfer and Advancement Act and 1 CFR
Part 51
J. Executive Order 12898: Federal Actions To Address
Environmental Justice in Minority Populations and Low-Income
Populations
IV. References

I. General Information

A. Executive Summary and Background

EPA is proposing new and revised listings after its evaluation of
human health and environmental information for these substitutes under
the Significant New Alternatives Policy (SNAP) program. The Agency is
proposing action on these new listings in the refrigeration and air
conditioning (AC) sector based on the information that EPA has included
in the docket. This proposed action would provide new refrigerant
options, thereby increasing flexibility for industry, in specific uses.
This action proposes to list new alternatives for the refrigeration
and AC sector. Specifically, EPA is proposing to:
<bullet> List hydrofluoroolefin (HFO)-1234yf, HFO-1234ze(E), R-
454C, R-455A, R-457A, and R-516A as acceptable, subject to use
conditions, for use in new retail food refrigeration equipment (i.e.,
stand-alone units, remote condensing units, supermarket systems, and
refrigerated food processing and dispensing equipment);
<bullet> List R-454A as acceptable, subject to use conditions, for
use in new remote condensing units and supermarket systems;
<bullet> List R-290 (propane) as acceptable, subject to use
conditions, for use in new refrigerated food processing and dispensing
equipment and revise the existing use conditions for R-290 in new
stand-alone units.
<bullet> List hydrofluorocarbon (HFC)-32, HFO-1234yf, R-454A, R-
454B, R-454C, R-455A, R-457A, and R-516A as acceptable, subject to use
conditions, for use in new commercial ice machines;
<bullet> Revise the existing use conditions for R-290 for use in
new self-contained commercial ice machines;
<bullet> List HFO-1234yf, HFO-1234ze(E), R-454A, R-454C, R-455A, R-
457A, and R-516A as acceptable, subject to use conditions, for use in
new chillers for industrial process refrigeration (IPR);
<bullet> List HFC-32 and R-454B as acceptable, subject to use
conditions, for use in new chillers for IPR;
<bullet> List HFO-1234yf, HFO-1234ze(E), R-454A, R-454C, R-455A, R-
457A, and R-516A as acceptable, subject to use conditions, for use in
new cold storage warehouses; and
<bullet> List HFO-1234yf, HFO-1234ze(E), R-454C, R-455A, R-457A,
and R-516A as acceptable, subject to use conditions, for use in new ice
skating rinks using a remote compressor.
In general, the proposed use conditions are consistent across the
various substitutes and end-uses contained in this proposal. Because of
this similarity, EPA discusses the proposed use conditions that would
apply to all five end-uses in section II.H. In summary, the common use
conditions proposed are:

[[Page 33724]]

(1) These refrigerants may be used only in new equipment, designed
specifically and clearly identified for use with the refrigerant. None
of these substitutes may be used as a conversion or ``retrofit''
refrigerant for existing equipment.
(2) These refrigerants may be used only in equipment that meet all
requirements listed in the 2nd edition, dated October 27, 2021, of UL
\1\ Standard 60335-2-89, ``Household and Similar Electrical
Appliances--Safety--Part 2-89: Requirements for Commercial
Refrigerating Appliances and Ice-Makers with an Incorporated or Remote
Refrigerant Unit or Motor-Compressor'' (hereafter ``UL 60335-2-89'').
For refrigerants that already have listings that incorporate by
reference earlier UL standards, EPA is proposing a transition period
when equipment may meet either the earlier UL standard or UL 60335-2-
89.
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\1\ UL, formerly known as Underwriters Laboratories.
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(3) These refrigerants must be used with warning labels on the
equipment and packaging that are similar to or match verbatim those
required by UL 60335-2-89.
(4) Equipment must be marked with distinguishing red color-coded
hoses and piping to indicate use of a flammable refrigerant and marked
service ports, pipes, hoses, and other devices through which the
refrigerant is serviced.
(5) These refrigerants must be used with equipment and packaging
marked with the Global Harmonized System of Classification and
Labelling of Chemicals (GHS) symbol for hazard category 1 flammable
gases.
Additional use conditions specific to particular end-uses may also
apply and are discussed with each proposed listing. The regulatory text
of the proposed listings, including the proposed use conditions and
further information, appears in tables at the end of this document. The
proposed new listings would appear in appendix Y to 40 Code of Federal
Regulations (CFR) part 82, subpart G. The proposed revised listings for
R-290 in new retail food refrigeration equipment (stand-alone units
only) and in new self-contained commercial ice machines would appear,
respectively, in appendices R and V to 40 CFR part 82, subpart G.
There may be other legal obligations pertaining to the manufacture,
use, handling, and disposal of the listed substitutes that are not
included in the information in the tables (e.g., the CAA section
608(c)(2) venting prohibition or Department of Transportation (DOT)
requirements for transport of flammable gases). Flammable refrigerants
being recovered or otherwise disposed of from commercial or industrial
refrigeration equipment are likely to be hazardous waste under the
Resource Conservation and Recovery Act (RCRA) (see 40 CFR parts 260
through 270).
In addition, EPA is proposing to exempt R-290 used in the
refrigerated food processing and dispensing end-use from the CAA
section 608(c)(2) prohibition on knowingly venting, releasing, or
disposing of substitute refrigerants on the basis of current evidence
that the venting, release, or disposal of this substance in this end-
use does not pose a threat to the environment.
SNAP Program Background
The SNAP program implements CAA section 612. Several major
provisions of section 612 are:
1. Rulemaking
Section 612(c) requires EPA to promulgate rules making it unlawful
to replace any class I (chlorofluorocarbon (CFC), halon, carbon
tetrachloride, methyl chloroform, methyl bromide,
hydrobromofluorocarbon, and chlorobromomethane) or class II
(hydrochlorofluorocarbon (HCFC)) ozone-depleting substance (ODS) with
any substitute that the Administrator determines may present adverse
effects to human health or the environment where the Administrator has
identified an alternative that (1) reduces the overall risk to human
health and the environment and (2) is currently or potentially
available.
2. Listing of Unacceptable/Acceptable Substitutes
Section 612(c) requires EPA to publish a list of the substitutes
that it finds to be unacceptable for specific uses and to publish a
corresponding list of acceptable substitutes for specific uses.
3. Petition Process
Section 612(d) grants the right to any person to petition EPA to
add a substance to, or delete a substance from, the lists published in
accordance with section 612(c).
4. 90-Day Notification
Section 612(e) directs EPA to require any person who produces a
chemical substitute for a class I substance to notify the Agency not
less than 90 days before a new or existing chemical is introduced into
interstate commerce for significant new use as a substitute for a class
I substance. The producer must also provide the Agency with the
producer's unpublished health and safety studies on such substitutes.
The regulations for the SNAP program are promulgated at 40 CFR part
82, subpart G, and the Agency's process for reviewing SNAP submissions
is described in regulations at 40 CFR 82.180. Under these rules, the
Agency has identified five types of listing decisions: acceptable;
acceptable subject to use conditions; acceptable subject to narrowed
use limits; unacceptable; and pending (40 CFR 82.180(b)). Use
conditions and narrowed use limits are both considered ``use
restrictions.'' Substitutes that are deemed acceptable with no use
restrictions (no use conditions or narrowed use limits) can be used for
all applications within the relevant end-uses in the sector. After
reviewing a substitute, the Agency may determine that a substitute is
acceptable only if certain conditions in the way that the substitute is
used are met to minimize risks to human health and the environment. EPA
describes such substitutes as ``acceptable subject to use conditions''
(40 CFR 82.180(b)(2)). For some substitutes, the Agency may permit a
narrowed range of use within an end-use or sector. For example, the
Agency may limit the use of a substitute to certain end-uses or
specific applications within an industry sector. EPA describes these
substitutes as ``acceptable subject to narrowed use limits.'' Under the
narrowed use limit, users intending to adopt these substitutes ``must
ascertain that other alternatives are not technically feasible.'' (40
CFR 82.180(b)(3)).
In making decisions regarding whether a substitute is acceptable or
unacceptable, and whether substitutes present risks that are lower than
or comparable to risks from other substitutes that are currently or
potentially available in the end-uses under consideration, EPA examines
the following criteria in 40 CFR 82.180(a)(7): (i) atmospheric effects
and related health and environmental impacts; (ii) general population
risks from ambient exposure to compounds with direct toxicity and to
increased ground-level ozone; (iii) ecosystem risks; (iv) occupational
risks; (v) consumer risks; (vi) flammability; and (vii) cost and
availability of the substitute.
Many SNAP listings include ``comments'' or ``further information''
to provide additional information on substitutes. Since this additional
information is not part of the regulatory decision under SNAP, these
statements are not binding for use of the substitute

[[Page 33725]]

under the SNAP program. However, regulatory requirements so listed are
binding under other regulatory programs (e.g., worker protection
regulations promulgated by the U.S. Occupational Safety and Health
Administration (OSHA)). The ``further information'' classification does
not necessarily include all other legal obligations pertaining to the
use of the substitute. While the items listed are not legally binding
under the SNAP program, EPA encourages users of substitutes to apply
all statements in the ``Further Information'' column in their use of
these substitutes. In many instances, the information simply refers to
sound operating practices that have already been identified in existing
industry and/or building codes or standards. Thus, many of the
statements, if adopted, would not require the affected user to make
significant changes in existing operating practices.
For additional information on the SNAP program, visit the SNAP
website at <a href="https://www.epa.gov/snap">https://www.epa.gov/snap</a>. The full lists of acceptable
substitutes for ODS in all industrial sectors are available at <a href="https://www.epa.gov/snap/snap-substitutes-sector">https://www.epa.gov/snap/snap-substitutes-sector</a>. For more information on the
Agency's process for administering the SNAP program or criteria for
evaluation of substitutes, refer to the initial SNAP rulemaking
published March 18, 1994 (59 FR13044), codified at 40 CFR part 82,
subpart G. SNAP decisions and the appropriate Federal Register
citations can be found at <a href="https://www.epa.gov/snap/snap-regulations">https://www.epa.gov/snap/snap-regulations</a>.
Substitutes listed as unacceptable; acceptable, subject to narrowed use
limits; or acceptable, subject to use conditions, are also listed in
the appendices to 40 CFR part 82, subpart G.

Background on requirements concerning venting, release, or
disposal of refrigerants and refrigerant substitutes under CAA
section 608

The statutory requirements concerning venting, release, or disposal
of ODS refrigerants and substitutes for ODS used as refrigerants are
under CAA section 608, and EPA's authority to promulgate the regulatory
revisions in this action is based in part on CAA section 608. Section
608 of the Act, as amended, titled National Recycling and Emission
Reduction Program, requires, among other things, that EPA establish
regulations governing the use and disposal of ODS used as refrigerants,
such as certain CFCs and HCFCs, during the service, repair, or disposal
of appliances and IPR.\2\ Section 608(c)(1) provides that it is
unlawful for any person in the course of maintaining, servicing,
repairing, or disposing of an appliance (or IPR) to knowingly vent, or
otherwise knowingly release or dispose of, any class I or class II
substance used as a refrigerant in that appliance (or IPR) in a manner
which permits the ODS to enter the environment.
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\2\ Additional information about the 608 Refrigerant Management
Program is available in EPA's rules implementing that program, such
as rules published on May 14, 1993 (58 FR 28660), November 18, 2016
(81 FR 82272), and March 11, 2020 (85 FR 14150).
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Section 608(c)(2) extends the prohibition in section 608(c)(1) to
knowingly venting or otherwise knowingly releasing or disposing of any
refrigerant substitute for class I or class II substances by any person
maintaining, servicing, repairing, or disposing of appliances or IPR.
This prohibition applies to any substitute refrigerant unless the
Administrator determines that such venting, releasing, or disposing
does not pose a threat to the environment. Thus, section 608(c)
provides EPA authority to promulgate regulations to interpret,
implement, and enforce this prohibition on venting, releasing, or
disposing of class I or class II substances and their refrigerant
substitutes, which we also refer to as the ``venting prohibition'' in
this proposed action. EPA's authority under section 608(c) includes
authority to implement section 608(c)(2) by exempting certain
substitutes for class I or class II substances from the venting
prohibition when the Administrator determines that such venting,
release, or disposal does not pose a threat to the environment.
EPA issued a rule on March 12, 2004 (69 FR 11946), and a second
rule on April 13, 2005 (70 FR 19273), clarifying how the venting
prohibition in section 608(c) applies to substitutes for CFC and HCFC
refrigerants (e.g., HFCs and perfluorocarbons (PFCs)). These
regulations are codified at 40 CFR part 82, subpart F. In relevant
part, they provide that no person maintaining, servicing, repairing, or
disposing of appliances may knowingly vent or otherwise release into
the environment any refrigerant or substitute from such appliances,
with the exception of certain specified substitutes in the specified
end-uses, as provided in 40 CFR 82.154(a).
EPA has exempted from the venting prohibition several hydrocarbon
(HC) refrigerant substitutes, including R-290, in specific end-uses
where the Agency had also listed the substitutes as acceptable, subject
to use conditions, under the SNAP program. See, for example, EPA's
regulations issued May 23, 2014 (79 FR 29682), April 10, 2015 (80 FR
19453), and December 1, 2016 (81 FR 86778).\3\ Those regulatory
exemptions do not apply to blends of HCs with other refrigerants or
containing any amount of any CFC, HCFC, HFC, or PFC. The current
exemptions for R-290 by end-use are codified at 40 CFR
82.154(a)(1)(viii).
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\3\ The United States Court of Appeals for the District of
Columbia Circuit (``the court'') issued a partial vacatur of the
December 1, 2016 rule ```to the extent' it required manufacturers to
replace already lawfully installed HFC substitutes.'' See Mexichem
Fluor, Inc. v. EPA, Judgment, Case No. 17-1024 (D.C. Cir., April 5,
2019), 760 Fed. Appx. 6 (Mem). The court's decision on the December
1, 2016 rule did not affect the portion of that rule that exempted
certain HC refrigerant substitutes from the venting prohibition.
This proposed rule is not EPA's response to the court's decision.
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In establishing those exemptions, EPA determined that for the
purposes of CAA section 608(c)(2), the venting, release, or disposal of
such HC refrigerant substitutes in the specified end-uses does not pose
a threat to the environment, considering both the inherent
characteristics of these substances and the limited quantities used in
the relevant applications., see, e.g., December 1, 2016 (81 FR 86778).
EPA further concluded that other authorities, controls, or practices
that apply to such refrigerant substitutes help to mitigate
environmental risk from the release of those saturated HC refrigerant
substitutes.

B. Does this action apply to me?

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

<bullet> Plumbing, Heating, and Air Conditioning Contractors (NAICS
238220)
<bullet> All Other Basic Organic Chemical Manufacturing (NAICS 325199)
<bullet> Air Conditioning and Warm Air Heating Equipment and Commercial
and Industrial Refrigeration Equipment Manufacturing (NAICS 333415)
<bullet> Refrigeration Equipment and Supplies Merchant Wholesalers
(NAICS 423740)
<bullet> Recyclable Material Merchant Wholesalers (NAICS 423930)
<bullet> Supermarkets and Other Grocery (except Convenience) Stores
(NAICS 445110)
<bullet> Convenience Stores (NAICS 445120)
<bullet> Limited-Service Restaurants (NAICS 722211)
<bullet> Appliance Repair and Maintenance (NAICS 811412)

[[Page 33726]]

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

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

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

AC--Air Conditioning
AEL--Acceptable Exposure Limit
AIHA--American Industrial Hygiene Association
ANSI--American National Standards Institute
ASHRAE--American Society of Heating, Refrigerating and Air-
Conditioning Engineers
ASTM--American Society for Testing and Materials
ATEL--Acute Toxicity Exposure Limit
CAA--Clean Air Act
CAS Reg. No.--Chemical Abstracts Service Registry Identification
Number
CBI--Confidential Business Information
CFC--Chlorofluorocarbon
CFR--Code of Federal Regulations
CO<INF>2</INF>--Carbon Dioxide
DOE--United States Department of Energy
DOT--United States Department of Transportation
DX--Direct Heat Exchange
EPA--United States Environmental Protection Agency
FR--Federal Register
GHS--Global Harmonized System of Classification and Labelling of
Chemicals
GWP--Global Warming Potential
HC--Hydrocarbon
HCFC--Hydrochlorofluorocarbon
HCFO--Hydrochlorofluoroolefin
HFC--Hydrofluorocarbon
HFO--Hydrofluoroolefin
HP--Heat Pump
IBC--International Building Code
ICC--International Code Council
ICF--ICF International, Inc.
IEC--International Electrotechnical Commission
IPCC--Intergovernmental Panel on Climate Change
IPR--Industrial Process Refrigeration
ISO--International Organisation for Standardisation
LFL--Lower Flammability Limit
MIR--Maximum Incremental Reactivity
NAAQS--National Ambient Air Quality Standards
NAICS--North American Industrial Classification System
NARA--National Archives and Records Administration
ODP--Ozone Depletion Potential
ODS--Ozone Depleting Substances
OMB--United States Office of Management and Budget
OSHA--United States Occupational Safety and Health Administration
PEL--Permissible Exposure Limit
PFC--Perfluorocarbons
PMS--Pantone[supreg] Matching System
ppm--Parts Per Million
PRA--Paperwork Reduction Act
RCRA--Resource Conservation and Recovery Act
RFA--Regulatory Flexibility Act
SDS--Safety Data Sheet
SIP--State Implementation Plan
TLV--Threshold Limit Value
TSCA--Toxic Substances Control Act
TWA--Time Weighted Average
UL--UL, formerly known as Underwriters Laboratories, Inc.
UMRA--Unfunded Mandates Reform Act
VOC--Volatile Organic Compound, Volatile Organic Compounds
WEEL--Workplace Environmental Exposure Limit
WMO--World Meteorological Organization

II. What is EPA proposing in this action?

A. Retail Food Refrigeration--Proposed Listing of HFO-1234yf, HFO-
1234ze(E), R-454C, R-455A, R-457A, and R-516A as Acceptable, Subject to
Use Conditions, for Use in New Stand-Alone Units, Remote Condensing
Units, Supermarket Systems, and Refrigerated Food Processing and
Dispensing Equipment and Proposed Listing of R-454A as Acceptable,
Subject to Use Conditions, for Use in New Remote Condensing Units and
Supermarkets Systems

EPA is proposing to list HFO-1234yf, HFO-1234ze(E), R-454C, R-455A,
R-457A, and R-516A as acceptable, subject to use conditions, for use in
all end-use categories under retail food refrigeration (i.e., stand-
alone units, remote condensing units, supermarket systems, and
refrigerated food processing and dispensing equipment). EPA is also
proposing to list R-454A as acceptable, subject to use conditions, for
use in two end-use categories under retail food refrigeration (remote
condensing units and supermarket systems).
EPA is proposing several use conditions for these end-use
categories that are identical to those proposed for other end-uses
(commercial ice machines, IPR, cold storage warehouses, and ice skating
rinks with a remote compressor) discussed elsewhere in this proposal.
Because of this similarity, EPA discusses the use conditions that would
apply to all five end-uses in Section II.H. In summary, the common use
conditions EPA is proposing include the following: restricting the use
of each refrigerant to new equipment that is specifically designed for
that refrigerant; use consistent with the 2nd edition of UL 60335-2-89,
including testing, charge sizes, ventilation, usage space requirements,
and certain hazard warnings and markings; and requirements for warning
labels and markings on equipment to inform consumers, technicians, and
first responders of potential flammability hazards.
For use of these substitutes in retail food refrigeration
equipment, EPA is also proposing a use condition related to adherence
to the American National Standards Institute (ANSI)/American Society of
Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) Standard
15-2022 ``Safety Standard for Refrigeration Systems'' (hereafter
``ASHRAE 15-2022''). Specifically, we are proposing that these
refrigerants may only be used in commercial refrigeration equipment
that meets all requirements listed in ASHRAE 15-2022. In cases where
the final rule includes requirements that are different than those of
ASHRAE 15-2022, EPA is proposing that the appliance would need to meet
the requirements of this rule in place of the requirements in ASHRAE
15-2022. This additional use condition is discussed further in section
II.A.4.
EPA is also proposing the following use condition for R-454A in
supermarkets and remote condensing units: this substitute may only be
used either in equipment with a refrigerant charge capacity less than
200 pounds or in the high-temperature side of a cascade system.
1. Background on Retail Food Refrigeration
Retail food refrigeration, an end-use within the SNAP program,
encompasses the equipment used for storing and displaying (generally
for sale) food and beverages at different temperatures necessary for
the different products (e.g., chilled and frozen food). The designs and
refrigerating capacities of equipment vary widely to ensure the proper
temperatures are achieved and maintained.
Retail food refrigeration is composed of four categories of
equipment: stand-alone units; refrigerated food processing and
dispensing equipment; remote condensing units; and supermarket systems.
EPA treats each of these four end-use categories as a separate end-use
for purposes of our comparisons of the overall impact on human health
and the environment and of the availability of refrigerants.
Stand-alone units are refrigerators, freezers, and reach-in coolers
(either

[[Page 33727]]

open or with doors) where all refrigeration components are integrated
and, for the smallest types, the refrigeration circuit is entirely
brazed or welded. These systems are charged with refrigerant at the
factory and typically require only an electricity supply to begin
operation. Such systems are used to chill and temporarily store
perishable items for commercial sale, such as beverages and food.
Refrigerated food processing and dispensing equipment dispenses and
often processes a variety of food and beverage products. For instance,
some such equipment will process the product by combining ingredients,
mixing, and preparing it at the proper temperature, while others
function mainly as a holding tank to deliver the product at the desired
temperature or to deliver chilled ingredients for processing, mixing,
and preparation. Some may use a refrigerant in a heat pump, or utilize
waste heat from the cooling system, to provide hot beverages. Some may
also provide heating functions for melting or dislodging ice or for
sanitation purposes.
Refrigerated food processing and dispensing equipment can be self-
contained or can be connected via piping to a dedicated condensing unit
located elsewhere. Equipment within this end-use category include but
are not limited to refrigerated equipment used to process and dispense
beverages and food such as: chilled and frozen beverages (carbonated
and uncarbonated, alcoholic and nonalcoholic); frozen custards, gelato,
ice cream, Italian ice, sorbets, and yogurts; milkshakes, ``slushies''
and smoothies, and whipped cream.
Remote condensing units exhibit refrigerating capacities ranging
typically from 1kW to 20kW (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, which is 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. Remote condensing units are
commonly installed in convenience stores and specialty shops such as
bakeries and butcher shops.
Typical supermarket systems are also known as multiplex or
centralized systems. They operate with racks of compressors installed
in a machinery room; different compressors turn on to match the
refrigeration load necessary to maintain temperatures. Two main design
classifications are used: direct and indirect systems. In the United
States, direct systems are the most widespread. The plurality of
supermarkets in the United States use centralized direct expansion (DX)
systems to cool their display cases.\4\ The refrigerant circulates 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. The supermarket walk-in cold rooms are
often integrated into the system and cooled similarly, but an
alternative option is to provide a dedicated condensing unit for a
given storage room. 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, with five to ten such systems in a
store.
---------------------------------------------------------------------------

\4\ <a href="http://www.epa.gov/greenchill/advanced-refrigeration">www.epa.gov/greenchill/advanced-refrigeration</a>.
---------------------------------------------------------------------------

Indirect supermarket system designs include secondary loop systems
and cascade refrigeration. Indirect systems use a chiller or other
refrigeration system to cool a secondary fluid that is often circulated
throughout the store to the cases. Examples of secondary fluids include
water, air, HCs, ammonia, and carbon dioxide (CO<INF>2</INF>). Compact
chiller versions of an indirect system rely on a lineup of ten to 20
units, each using small charge sizes. As the refrigeration load
changes, more or fewer of the chillers are active. Compact chillers are
used in a secondary loop system whereby the chillers cool a secondary
fluid that is then circulated throughout the store to the display
cases. Each compact chiller is an independent unit with its own
refrigerant charge, reducing the potential for refrigerant to be
released from leaks or for a catastrophic failure. Cascade systems use
a compressor to raise the low-temperature, secondary fluid from low-
temperature conditions up to an intermediate temperature while a
separate, primary refrigerant system uses a different, higher
temperature refrigerant to condense the secondary fluid. Each system
within the cascade design contains its own refrigerant charge, allowing
the use of different refrigerants in each system. This application has
generally used a lower global warming potential (GWP) refrigerant,
specifically CO<INF>2</INF> (R-744), in the low-temperature system,
with a variety of refrigerants in the high temperature system.
Refrigerant choice depends on the refrigerant charge, ambient
temperatures and the temperature required, system performance, energy
efficiency, and health, safety and environmental considerations, among
other things. In addition to regulations pursuant to the SNAP program,
other federal or local regulations may also affect refrigerant choice.
For instance, regulations from OSHA may restrict or place requirements
on the use of some refrigerants, such as ammonia (R-717). Building
codes from local and state agencies may also incorporate limits on the
types and amounts of particular refrigerants used. There are and will
continue to be multiple factors that retailers must consider when
selecting the refrigerant and operating system design, including:
energy efficiency; system performance; potential impact on community
safety; ambient temperatures; risk to personnel safety; cost; and
minimization of direct and indirect environmental impacts.
2. What are the ASHRAE classifications for refrigerant flammability?
The ANSI/ASHRAE Standard 34-2022 ``Designation and Safety
Classification of Refrigerants'' (hereafter ``ASHRAE 34-2022'') assigns
a safety group classification for each refrigerant which consists of
two to three alphanumeric characters (e.g., A2L or B1). The initial
capital letter indicates the toxicity, and the numeral denotes the
flammability. ASHRAE classifies Class A refrigerants as refrigerants
for which toxicity has not been identified at concentrations less than
or equal to 400 parts per million (ppm) by volume, based on data used
to determine threshold limit value-time-weighted average (TLV-TWA) or
consistent indices. Class B signifies refrigerants for which there is
evidence of toxicity at concentrations below 400 ppm by volume, based
on data used to determine TLV-TWA or consistent indices.
The refrigerants are also assigned a flammability classification of
1, 2, 2L, or 3. Tests for flammability are conducted in accordance with
American Society for Testing and Materials (ASTM) E681 using a spark
ignition source at 140 [deg]F (60 [deg]C) and 14.7 psia (101.3 kPa).\5\
The flammability classification ``1'' is given to refrigerants that,
when tested, show no flame propagation. The flammability classification
``2'' is given to refrigerants that, when tested, exhibit flame
propagation, have a heat of combustion

[[Page 33728]]

less than 19,000 kJ/kg (8,169 Btu/lb), and have a lower flammability
limit (LFL) greater than 0.10 kg/m\3\. The flammability classification
``2L'' is given to refrigerants that, when tested, exhibit flame
propagation, have a heat of combustion less than 19,000 kJ/kg (8,169
Btu/lb), have an LFL greater than 0.10 kg/m\3\, and have a maximum
burning velocity of 10 cm/s or lower when tested in dry air at 73.4
[deg]F (23.0 [deg]C) and 14.7 psi (101.3 kPa). The flammability
classification ``3'' is given to refrigerants that, when tested,
exhibit flame propagation and that either have a heat of combustion of
19,000 kJ/kg (8,169 Btu/lb) or greater or have an LFL of 0.10 kg/m\3\
or lower.
---------------------------------------------------------------------------

\5\ ASHRAE, 2022b. ANSI/ASHRAE Standard 34-2022: Designation and
Safety Classification of Refrigerants.
---------------------------------------------------------------------------

For flammability classifications, refrigerant blends are designated
based on the worst case of formulation for flammability and the worst
case of fractionation for flammability determined for the blend.
[GRAPHIC] [TIFF OMITTED] TP24MY23.000

Using these safety group classifications, ASHRAE 34-2022
categorizes HFO-1234yf, HFO-1234ze(E), HFC-32 and the refrigerant
blends R-454A, R-454B, R-454C, R-455A, R-457A, and R-516A, which are
discussed in this section of this proposed rule, as being in the A2L
Safety Group, while R-290 is in the A3 Safety Group.
3. What are HFO-1234yf, HFO-1234ze(E), R-454A, R-454C, R-455A, R-457A,
and R-516A and how do they compare to other refrigerants in the same
end-use?
HFO-1234yf and HFO-1234ze(E) are lower flammability refrigerants,
and R-454A, R-454C, R-455A, R-457A, and R-516A are lower flammability
refrigerant blends, all with an ASHRAE safety classification of A2L.\6\
The respective Chemical Abstracts Service Registry Identification
Numbers (CAS Reg. Nos.) of HFO-1234yf, HFO-1234ze(E), and the
components of the refrigerant blends are listed here.
---------------------------------------------------------------------------

\6\ EPA previously listed HFO-1234yf as acceptable, subject to
use conditions, in motor vehicle AC in light-duty vehicles (74 FR
53445, October 19, 2009), in heavy-duty pickup trucks and complete
heavy-duty vans (81 FR 86778, December 1, 2016) and in nonroad
vehicles and service fittings for small refrigerant cans (87 FR
26276, May 4, 2022). EPA previously listed R-454A, R-454C, and R-
457A as acceptable, subject to use conditions, as a substitute in
residential and light commercial AC and heat pumps (HPs) (86 FR
24444, May 6, 2021).
---------------------------------------------------------------------------

HFO-1234yf, also known by the trade names ``Solstice[supreg] yf''
and ``Opteon TM YF,'' is also known as 2,3,3,3-
tetrafluoroprop-1-ene (CAS Reg. No. 754-12-1). HFO-1234ze(E), also
known by the trade names ``Solstice[supreg] ze and Solstice[supreg]
1234ze'', is also known as trans-1,3,3,3,tetrafluoroprop-1-ene (CAS
Reg. No. 29118-24-9). R-516A, also known by the trade name
``Forane[supreg] 516A,'' is a blend consisting of 77.5 percent HFO-
1234yf, 14 percent HFC-152a, and 8.5 percent HFC-134a. R-457A, also
known by the trade name ``Forane[supreg] 457A,'' is a blend consisting
of 18 percent HFC-32, 12 percent HFC-152a, and 70 percent HFO-1234yf.
R-455A, also known by the trade name ``Solstice[supreg] L40X,'' is a
blend consisting of 21.5 percent HFC-32, 75.5 percent HFO-1234yf, and
three percent R-744 (CO<INF>2</INF>). R-454A, also known by the trade
name ``OpteonTM XL 40,'' is a blend consisting of 35 percent
HFC-32 and 65 percent HFO-1234yf. R-454C, also known by the trade name
``OpteonTM XL 20,'' is a blend consisting of 21.5 percent
HFC-32 and 78.5 percent HFO-1234yf.
Redacted submissions and supporting documentation for HFO-1234yf,
HFO-1234ze(E), R-454A, R-454C, R-455A, R-457A, and R-516A are provided
in the docket for this proposed rule (EPA-HQ-OAR-2023-0043) at <a href="https://www.regulations.gov">https://www.regulations.gov</a>. EPA performed a risk screening assessment to
examine the health and environmental risks of each of these
substitutes. These risk screens are available in the docket for this
proposed rule.7 8 9 10 11 12 13
---------------------------------------------------------------------------

\7\ ICF, 2023a. Risk Screen on Substitutes in Retail Food
Refrigeration (New Equipment); Substitute: HFO-1234yf.
\8\ ICF, 2023b. Risk Screen on Substitutes in Retail Food
Refrigeration (New Equipment); Substitute: HFO-1234ze(E)
(Solstice[supreg] ze, Solstice[supreg] 1234ze)
\9\ ICF, 2023c. Risk Screen on Substitutes in Retail Food
Refrigeration (New Equipment); Substitute: R-454A (Opteon[supreg]
XL40).
\10\ ICF, 2023d. Risk Screen on Substitutes in Retail Food
Refrigeration (New Equipment); Substitute: R-454C
(OpteonTM XL20).
\11\ ICF, 2023e. Risk Screen on Substitutes in Retail Food
Refrigeration (New Equipment); Substitute: R-455A (Solstice[supreg]
L40X).
\12\ ICF, 2023f. Risk Screen on Substitutes in Retail Food
Refrigeration (New Equipment); Substitute: R-457A (Forane[supreg]
457A).
\13\ ICF, 2023g. Risk Screen on Substitutes in Retail Food
Refrigeration (New Equipment); Substitute: R-516A (Forane[supreg]
516A).
---------------------------------------------------------------------------

Environmental information: HFO-1234yf, HFO-1234ze(E) and R-454A, R-
454C, R-455A, R-457A, and R-516A have ozone depletion potentials (ODPs)
of zero.

[[Page 33729]]

HFO-1234yf has a GWP of less than four.14 15 16 HFO-
1234ze(E) has a GWP of less than six.17 18 The refrigerant
blends are made up of the components HFC-32, HFC-125, HFC-152a,
CO<INF>2</INF>, and HFO-1234yf, which have GWPs of 675, 3,500, 124,
one, and less than four, respectively.\19\ If these values are weighted
by mass percentage, then R-454A, R-454C, R-455A, R-457A, and R-516A
have GWPs of about 240, 150, 146, 140, and 142, respectively.
---------------------------------------------------------------------------

\14\ World Meteorological Organization (2018). Burkholder et al.
Appendix A, Table A-1 in Scientific Assessment of Ozone Depletion:
2018, Global Ozone Research and Monitoring Project, Report No. 58,
World Meteorological Organization, Geneva, Switzerland, <a href="https://ozone.unep.org/science/assessment/sap">https://ozone.unep.org/science/assessment/sap</a>. (WMO, 2018)
\15\ Nielsen et al., 2007. Nielsen, O.J., Javadi, M.S., Sulbaek
Andersen, M.P., Hurley, M.D., Wallington, T.J., Singh, R. 2007.
Atmospheric chemistry of CF3CF=CH2: Kinetics and mechanisms of gas-
phase reactions with Cl atoms, OH radicals, and O3. Chemical Physics
Letters 439, 18-22. Available online at: www.cogci.dk/network/
OJN_174_CF3CF=CH2.pdf.
\16\ Hodnebrog [Oslash]. et al., 2013. Hodnebrog [Oslash].,
Etminan, M., Fuglestvedt, J.S., Marston, G., Myhre, G., Nielsen,
C.J., Shine, K.P., Wallington, T.J.: Global Warming Potentials and
Radiative Efficiencies of Halocarbons and Related Compounds: A
Comprehensive Review, Reviews of Geophysics, 51, 300-378,
doi:10.1002/rog.20013, 2013.
\17\ Javadi et al., 2008. Atmospheric chemistry of trans-
CF<INF>3</INF>CH=CHF: products and mechanisms of hydroxyl radical
and chlorine atom initiated oxidation,' M.S. Javadi, R.
S[oslash]ndergaard, O.J. Nielsen, M.D. Hurley, and T.J. Wellington,
Atmospheric Chemistry and Physics Discussions 8, 1069-1088, 2008.
\18\ Ibid.
\19\ Unless otherwise specified, GWP values are 100-year values
from Intergovernmental Panel on Climate Change (IPCC) (2007) Climate
Change 2007: The Physical Science Basis. Contribution of Working
Group I to the Fourth Assessment Report of the Intergovernmental
Panel on Climate Change. S. Solomon, D. Qin, M. Manning, Z. Chen, M.
Marquis, K.B. Averyt, M. Tignor and H.L. Miller (eds.). Cambridge
University Press. Cambridge, United Kingdom 996 pp.
---------------------------------------------------------------------------

HFO-1234yf, HFO-1234ze(E), and the other components of the
refrigerant blends, CO<INF>2</INF>, HFC-32, HFC-125, and HFC-152a, are
excluded from EPA's regulatory definition of volatile organic compounds
(VOC) (see 40 CFR 51.100(s)) addressing the development of State
Implementation Plans (SIPs) to attain and maintain the National Ambient
Air Quality Standards (NAAQS). That definition provides that ``any
compound of carbon'' which ``participates in atmospheric photochemical
reactions'' is considered a VOC unless expressly excluded in that
provision based on a determination of ``negligible photochemical
reactivity.''
Under section 608(c)(2) of the CAA and EPA's regulations at 40 CFR
82.154(a)(1), it is unlawful for any person, in the course of
maintaining, servicing, repairing, or disposing of an appliance or
industrial process refrigeration, to knowingly vent or otherwise
knowingly release or dispose of any substitute substance for a class I
or class II substance used as a refrigerant in such appliance (or
industrial process refrigeration) in a manner which permits such
substance to enter the environment. EPA has established certain limited
exemptions to this venting prohibition, as listed in 40 CFR
82.154(a)(1), but none of those exemptions apply to HFO-1234yf, HFO-
1234ze(E), R-454A, R-454C, R-455A, R-457A, or R-516A.
Flammability information: HFO-1234yf, HFO-1234ze(E), R-454A, R-
454C, R-455A, R-457A, and R-516A have lower flammability, with an
ASHRAE flammability classification of 2L.
Toxicity and exposure data: HFO-1234yf, HFO-1234ze(E), R-454A, R-
454C, R-455A, R-457A, and R-516A have an ASHRAE toxicity classification
of A (lower toxicity). Potential health effects of exposure to these
substitutes include drowsiness or dizziness. The substitutes may also
irritate the skin or eyes or cause frostbite. At sufficiently high
concentrations, the substitutes may cause irregular heartbeat. The
substitutes could cause asphyxiation if air is displaced by vapors in a
confined space. These potential health effects are common to many
refrigerants.
OSHA has established a Permissible Exposure Limit (PEL) for
CO<INF>2</INF> of 5,000 ppm as an 8-hr TWA. The American Industrial
Hygiene Association (AIHA) has established Workplace Environmental
Exposure Limits (WEELs) of 1,000 ppm as an 8-hr TWA for HFC-32, HFC-
125, and HFC-152a; 500 ppm as an 8-hr TWA for HFO-1234yf; and 800 ppm
as an 8-hr TWA for HFO-1234ze(E). The manufacturers of R-454A, R-454C,
R-455A, R-457A, and R-516A recommend acceptable exposure limits (AELs)
for the workplace, respectively, of 690, 615, 650, 650, and 590 ppm on
an 8-hr TWA for these blends.\20\ EPA anticipates that users will be
able to meet the OSHA PEL, AIHA WEELs, and manufacturers' AELs and
address potential health risks by following requirements and
recommendations in the manufacturers' safety data sheets (SDSs), the
use conditions proposed (including adherence to Underwriters
Laboratories (UL) 60335-2-89 and ASHRAE 15-2022), and other safety
precautions common to the refrigeration and AC industry.
---------------------------------------------------------------------------

\20\ The 8-hr TWA AEL recommendations of these refrigerant
blends are based upon a mass-weighting of the PEL and WEELs of their
components.
---------------------------------------------------------------------------

Comparison to other substitutes in these end-uses: HFO-1234yf, HFO-
1234ze(E), R-454A, R-454C, R-455A, R-457A, and R-516A all have an ODP
of zero, comparable to or lower than some of the acceptable substitutes
in these end-uses, such as CO<INF>2,</INF> with an ODP of zero.
For new refrigerated food processing and dispensing equipment, R-
454A, R-454C, R-455A, R-457A, and R-516A have GWPs ranging from 140 to
240, higher than to that of CO<INF>2</INF>, an acceptable substitute in
this end-use category, with a GWP of 1, while HFO-1234yf and HFO-
1234ze(E) have comparable GWPs to CO<INF>2</INF> of less than four and
less than six, respectively. The GWPs of HFO-1234yf, HFO-1234ze(E), R-
454A, R-454C, R-455A, R-457A, and R-516A are lower than those of other
acceptable substitutes for new refrigerated food processing and
dispensing equipment, such as R-450A, R-513A, and HFC-134a, with GWPs
of approximately 600, 630, and 1,430, respectively.
For new remote condensing units and supermarket systems, R-454A, R-
454C, R-455A, R-457A, and R-516A have GWPs ranging from 140 to 240,
higher than that of ammonia and CO<INF>2</INF>, acceptable substitutes
in these end-use categories, with GWPs of zero and one, respectively,
while HFO-1234yf and HFO-1234ze(E) have comparable GWPs to
CO<INF>2</INF> of less than four and less than six, respectively. The
GWPs of HFO-1234yf, HFO-1234ze(E), R-454A, R-454C, R-455A, R-457A, and
R-516A are lower than those of some of the acceptable substitutes for
new remote condensing units and new supermarket systems, such as R-
450A, R-513A, HFC-134a, R-407A, and R-404A, with GWPs of approximately
600, 630, 1,430, 2,110, and 2,630, respectively.
For new stand-alone units, R-454A, R-454C, R-455A, R-457A, and R-
516A have GWPs ranging from 140 to 240, higher than some of the
acceptable substitutes in this end-use category such as CO<INF>2</INF>,
R-290, and R-441A with GWPs of one, three, and less than five, while
HFO-1234yf and HFO-1234ze(E) have comparable GWPs to GWPs of
CO<INF>2</INF>, R-290, and R-441A of less than four and less than six,
respectively. The GWPs of HFO-1234yf, HFO-1234ze(E), R-454A, R-454C, R-
455A, R-457A, and R-516A are lower than some of the acceptable
substitutes for new stand-alone units, such as R-450A and R-513A, with
GWPs of 601 and 630, respectively.
Information regarding the toxicity of other available alternatives
is provided in the listing decisions previously made (see https://
www.epa.gov/snap/retail-

[[Page 33730]]

food-refrigeration). Toxicity risks of use, determined by the
likelihood of exceeding the exposure limit, of HFO-1234yf, HFO-
1234ze(E), R-454A, R-454C, R-455A, R-457A, and R-516A in these end-uses
are evaluated in the risk screens referenced above. The toxicity risks
of using HFO-1234yf, HFO-1234ze(E), R-454A, R-454C, R-455A, R-457A, and
R-516A in retail food refrigeration equipment are comparable to or
lower than toxicity risks of other available substitutes in the same
end-uses. Toxicity risks of the proposed refrigerants can be minimized
by use consistent with UL 60335-2-89--which would be required by our
proposed use conditions--and other industry standards, such as ASHRAE
15-2022--which applies under the use conditions--as well as
recommendations in the manufacturers' SDS and other safety precautions
common in the refrigeration and AC industry.
The flammability risks with HFO-1234yf, HFO-1234ze(E), R-454A, R-
454C, R-455A, R-457A, and R-516A in these end-uses, determined by the
likelihood of exceeding their respective lower flammability limits, are
evaluated in the risk screens referenced above. In conclusion, while
these refrigerants may pose greater flammability risk than other
available substitutes in the same end-uses, this risk can be minimized
by use consistent with ASHRAE 15-2022, which would be required for
equipment with certain charge sizes by our proposed use conditions, and
other industry standards such as UL 60335-2-89, which would also be
required by our proposed use conditions, as well as recommendations in
the manufacturers' SDS and other safety precautions common in the
refrigeration and AC industry. EPA is proposing use conditions that
maintain the low potential risk associated with the flammability of
these alternatives so that they will not pose significantly greater
risk than other acceptable substitutes in this end-use category.
In addition, the proposed substitutes have lower GWPs than most
other available alternatives for the same uses. The proposed
refrigerants provide additional lower-GWP options for situations where
other refrigerants with lower GWPs are not viable, such as for use of
HCs in systems with remote compressors or equipment requiring larger
charge sizes, or where equipment using CO<INF>2</INF> may not be able
to meet energy conservation standards from the U.S. Department of
Energy (DOE). Given the wide range of applications for retail food
refrigeration, not all refrigerants listed as acceptable under SNAP
will be suitable for the range of equipment in the retail food
refrigeration end-use or in the four end-use categories within retail
food refrigeration. To provide additional options to ensure the
availability of substitutes for the full range of retail food
refrigeration equipment with lower GWP and, therefore, lower overall
risk to human health and the environment, EPA is proposing the listings
for HFO-1234yf, HFO-1234ze(E), R-454C, R-455A, R-457A, and R-516A as
acceptable, subject to use conditions, for use in all types of retail
food refrigeration equipment. In addition, to account for the
additional challenges for finding lower GWP refrigerants with higher
capacity for remote condensing units and supermarket systems with
moderate charge sizes and for cascade systems, EPA is proposing to list
R-454A as acceptable, subject to use conditions, for use in remote
condensing units and supermarket systems with a charge size capacity
less than 200 pounds or for use in the high-temperature side of a
cascade system.
4. Why is EPA proposing these specific use conditions?
This proposal applies to end-uses covered by UL 60335-2-89. This
standard applies to commercial and industrial refrigeration equipment,
including the SNAP end-uses of retail food refrigeration, commercial
ice machines, IPR, cold storage warehouses, and ice skating rinks. In
addition, ASHRAE 15-2022 applies to these refrigeration systems.
The standard UL 60335-2-89 discussed in section II.H indicates that
refrigerant charges greater than a specific amount (called
``m<INF>3</INF>'' in the standard and based on the refrigerant's LFL)
are beyond its scope and that national standards might apply, such as
ASHRAE 15-2022. Hence, EPA is proposing to require adherence to both
standards as use conditions for remote condensing units and supermarket
systems, broadening the coverage under this proposed rule.
EPA is proposing to incorporate by reference ASHRAE 15-2022,
including all addenda published by the date of this proposal, in use
conditions that apply to use of the proposed A2L refrigerants in new
remote condensing units and supermarket systems. Where the requirements
specified in this proposed rule (if finalized) and ASHRAE 15-2022
differ, the requirements of this rule would apply.
A partial summary of ASHRAE 15-2022 is provided here for
information only. This is not meant to be a full explanation of the
standard or how it is applied. ASHRAE 15-2022 specifies requirements
for refrigeration systems, based on the safety group classification of
the refrigerant used, the type of occupancy in the location for which
the system is used, and whether refrigerant-containing parts of the
system enter the space or ductwork and so leakage in the space is
deemed ``probable.'' ``High-probability'' installations are those such
that leaks or failures will result in refrigerant entering occupied
space. As previously explained, HFO-1234yf, HFO-1234ze(E), R-454A, R-
454C, R-455A, R-457A, and R-516A are all classified as A2L
refrigerants. Occupancies are divided into six classifications:
institutional, public assembly, residential, commercial, large
mercantile, and industrial. Examples of these include jails, theaters,
apartment buildings, office buildings, shopping malls, and chemical
plants, respectively.
Sections 7.2 and 7.3 of ASHRAE 15-2022 determine the maximum amount
of refrigerant allowed in the system, while section 7.4 provides an
option to locate equipment outdoors or in a machinery room constructed
and maintained under conditions specified in the standard. Section 7.7
of ASHRAE 15-2022 addresses the A2L refrigerants in this proposal when
used in ``high-probability'' systems that are not for human comfort,
including requirements for nameplates, labels, refrigerant detectors
(under certain conditions), airflow initiation and other actions (if a
rise in refrigerant concentration is detected), and other restrictions.
EPA recognizes that ASHRAE 15-2022 is undergoing continuous
maintenance with publication of periodic addenda and is typically
updated and republished every three years. While this proposed rule
incorporates all addenda published by the date of this proposal, there
may be additional changes to ASHRAE 15-2022 by the time EPA issues a
final rule based upon this proposal. However, given EPA would not have
reviewed and proposed use conditions based on those changes, EPA is not
proposing to include addenda or other changes made to ASHRAE 15-2022
after the date of the proposed rule.
EPA is proposing to list R-454A as acceptable, subject to use
conditions, in supermarkets and remote condensing units with a use
condition that this substitute may only be used either in equipment
with a refrigerant charge capacity less than 200 pounds or in the high-
temperature side of a cascade system. The Agency is proposing this use
condition to allow use of R-454A less broadly than for the other

[[Page 33731]]

refrigerants proposed for use in remote condensing units and
supermarket systems because its GWP is higher than those of the other
proposed listings for these end-use categories (about 240, compared to
less than four to 150). EPA's understanding is that there are two
particular situations where use of refrigerants is likely to be more
constrained, and thus, additional refrigerant options may be helpful.
The first of those situations is in what the industry standard ASHRAE
15-2022 identifies as a refrigerating system having a ``high
probability'' that leaked refrigerant from a failed connection, seal,
or component could enter an occupied area. An example of such a
constraint is that ASHRAE 15-2022 and UL 60335-2-89 effectively set
charge limits for A2L refrigerants to less than 200 pounds for
applications inside a supermarket or convenience store that are open to
the general public. In contrast, larger charge sizes could be used in
``low-probability'' locations where the general public is unlikely to
come in contact with the refrigerant, such as systems used outdoors or
in a machinery room with access restricted to store employees. Where
the general public is unlikely to come into contact with any leaked
refrigerant, such as where charge sizes of 200 pounds or more of A2L
refrigerant would be allowed under the use conditions incorporating UL
60335-2-89 and ASHRAE 15-2022, there would be fewer space constraints
and greater flexibility in equipment design, so refrigeration system
designers can accommodate a narrower set of substitutes. Conversely,
where the general public is more likely to come into contact with any
leaked refrigerant in an interior space, refrigerant charge capacities
of a system would be less than 200 pounds; there would be more space
constraints, less flexibility in equipment design, and potentially
stricter code requirements, leading to a need for more refrigerant
options. Allowing the additional option of R-424A for supermarket
systems and remote condensing units with smaller refrigerant charges
would enable the use of a wider set of available substitutes to manage
safety (in particular, flammability and toxicity), as well as allowing
more options to achieve adequate performance where there may be more
constraints. Therefore, EPA is proposing to list R-454A as acceptable,
subject to use conditions, only for supermarket systems and remote
condensing units with a refrigerant charge capacity less than 200
pounds.
EPA is also proposing to list R-454A as acceptable, subject to use
conditions, for use in the high temperature side of cascade systems
used for supermarket systems and remote condensing units. As discussed
above in section II.A.1, ``Background on retail food refrigeration,''
each system of a cascade system uses a different refrigerant that is
most suitable for the given temperature range. High temperature
systems, or the ``high temperature side,'' have typically used HFCs as
a refrigerant; however, it is technologically achievable and has become
more common to use ammonia in the high temperature side. For lower
temperature systems, or the ``low temperature side'' of the cascade
system, low boiling refrigerants such as R-744 can be used.
Considerations for the choice of refrigerant on the high or low
temperature side of cascade systems are influenced by many factors
including, but not limited to, a refrigerant's toxicity and
flammability, its temperature glide, and its suitability for lower
temperature applications. EPA understands that use of flammable or
toxic refrigerants, such as ammonia, on the high temperature side of a
cascade may be limited in certain circumstances (e.g., based on
building codes and/or standards). The Agency considered whether to
propose to list R-454A as acceptable, subject to narrowed use limits.
For listings with narrowed use limits, the refrigerant user (e.g.,
equipment manufacturer or end user) intending to adopt a substitute
with narrowed use limits ``must ascertain that other alternatives are
not technically feasible.'' 40 CFR 82.180(b)(3). In the case of the
high side of a cascade system, EPA is currently aware of a limited
number of available options with a GWP below R-454A; therefore, EPA
does not consider it necessary to require users to first consider those
lower GWP refrigerants before selecting R-454A. The Agency notes that
there are multiple substitutes available for the low temperature side
of the cascade system with GWPs lower than that of R-454A, but there
are few options for the high temperature side of the cascade system.
Therefore, instead of proposing to list R-454A as acceptable, subject
to narrowed use limits and subject to use conditions, EPA is proposing
to list R-454A as acceptable, subject to use conditions, when it is
used in the high temperature side of cascade systems; this would expand
the refrigerant options that can comply with local building codes and
industry safety standards while meeting the more challenging
application of the high temperature side of a cascade system.
5. What additional information is EPA including in these proposed
listings?
EPA is providing additional information related to these proposed
listings. Since this additional information is not part of the
regulatory decision under SNAP, these statements are not binding for
use of the substitute under the SNAP program. The additional
information applies to multiple end-uses covered in this proposal.
Because of this similarity, EPA discusses the proposed additional
information in these proposed listings that would apply to all five
end-uses in section II.H.2 While the items listed are not legally
binding under the SNAP program, EPA encourages users of substitutes to
apply all statements in the FURTHER INFORMATION column in their use of
these substitutes.
6. On which topics is EPA specifically requesting comment?
EPA is requesting comment on all aspects of the proposed decision
to list HFO-1234yf, HFO-1234ze(E), R-454A, R-454C, R-455A, R-457A, and
R-516A acceptable, subject to use conditions, in new supermarket
systems and new remote condensing units as discussed in this section
II.A. We also request comment on the use conditions specifically for R-
454A, restricting its use to supermarket systems and remote condensing
units used either with a refrigerant charge capacity of less than 200
pounds or in the high temperature side of a cascade system, and whether
EPA should use different criteria in the final use conditions. We
request comment on our proposal to find HFO-1234yf, HFO-1234ze(E), R-
454C, R-455A, R-457A, and R-516A acceptable, subject to use conditions,
for use in new refrigerated food processing and dispensing equipment
(self-contained equipment) and new stand-alone units. EPA also seeks
specific comments on the use conditions including the proposed
requirements to comply with UL 60335-2-89, and for charge sizes larger
than ``m<INF>3</INF>,'' also to comply with ASHRAE 15-2022 including
addenda as of the date of this proposal. With respect to these
standards, EPA is requesting comment on the risk mitigation offered by
compliance with the current version of the standards proposed as use
conditions, i.e., UL 60335-2-89 and ASHRAE 15-2022, the nature of
updates proposed for these standards, and the expected timeline for
those updates. EPA is requesting comment on the applicability of the
2nd edition of UL 60335-2-89 to retail food refrigeration equipment,
including which types of equipment and under which

[[Page 33732]]

applications the standard applies, as well as on the applicability of
ASHRAE 15-2022 with the addenda published as of the date of this
proposal. Finally, EPA requests comment on whether there are any
specific cases of conflicts between UL 60335-2-89 and ASHRAE 15-2022
that require a clarification as to which standard should apply.

B. Retail Food Refrigeration--Proposed Listing of R-290 as Acceptable,
Subject to Use Conditions, for Use in New Refrigerated Food Processing
and Dispensing Equipment and Proposed Revision of Use Conditions
Provided in the Previous Listing of R-290 as Acceptable, Subject to Use
Conditions, for Use in Stand-Alone Units

This proposed listing for R-290 would be a new listing for one end-
use category under retail food refrigeration, i.e., new refrigerated
food processing and dispensing equipment. Further, EPA is also
proposing to revise use conditions provided in the previous listing of
R-290 as acceptable, subject to use conditions, for use in new stand-
alone units. More specifically, EPA previously listed R-290 as
acceptable, subject to use conditions, in new stand-alone units in SNAP
Rule 17 (76 FR 78832, December 20, 2011). In this document, we are
proposing to update those use conditions to be consistent with the most
recent U.S. national standard for retail food refrigeration equipment,
the 2nd edition of UL 60335-2-89. Similar use conditions apply to other
refrigerants with lower flammability as proposed in this SNAP action in
section II.A above. The proposed use conditions would be allowed for
such equipment manufactured on or after the effective date of any final
rule and would not apply to nor affect equipment manufactured before
the effective date of any final action and manufactured in compliance
with the SNAP requirements applicable at the time of manufacture.
This proposed revision to the use conditions would incorporate by
reference a different industry standard, changing the reference from
Supplement SB to the 10th edition of UL 471, ``Commercial Refrigerators
and Freezers,'' which is required in the current SNAP listing for R-
290, to the 2nd edition of UL 60335-2-89. EPA is proposing a transition
period during which stand-alone units manufactured with R-290 may
follow either the earlier standard UL 471 or UL 60335-2-89. After the
transition period ends, stand-alone units manufactured with R-290 would
need to follow UL 60335-2-89 for purposes of the SNAP program.
Several use conditions proposed for these end-use categories are
similar to those proposed for other end-uses. Because of this
similarity, EPA discusses the use conditions that would apply to all
five end-uses in section II.H. In summary, the common use conditions
proposed include the following: restricting the use of each refrigerant
to new equipment that is specifically designed for that refrigerant;
use consistent with the 2nd edition of UL 60335-2-89, including
testing, charge sizes, ventilation, usage space requirements, and
certain hazard warnings and markings; and requirements for warning
labels and markings on equipment to inform consumers, technicians, and
first responders of potential flammability hazards.
If the regulatory text is finalized as proposed, EPA would revise
the existing listing for R-290 in new stand-alone units in appendix R
to 40 CFR part 82, subpart G, and would add the new listing for R-290
in refrigerated food processing and dispensing units in appendix Y to
40 CFR part 82, subpart G. The proposed regulatory text contains
revised listing decisions for new stand-alone units in appendix R, as
well as certain other previous listings that EPA is republishing for
purposes of formatting for the Federal Register; EPA is not proposing
substantive changes to, and is not taking comment on, those earlier
decisions (e.g., listings for R-290, R-441A, and R-600a in household
refrigerators and freezers and in vending machines).
1. Background on Retail Food Refrigeration
See section II.A.1 for background on the retail food refrigeration
end-use and particularly for the stand-alone units and refrigerated
food processing and dispensing equipment end-use categories.
2. What are the ASHRAE classifications for refrigerant flammability?
ASHRAE 34-2022 categorizes R-290 as being in the A3 Safety Group.
See section II.A.2 for further discussion on ASHRAE classifications.
3. What is R-290 and how does it compare to other refrigerants in the
refrigerated food processing and dispensing equipment end-use category?
R-290 is also known as propane and has the formula
C<INF>3</INF>H<INF>8</INF> (CAS Reg. No. 74-98-6). Redacted submissions
and supporting documentation for R-290 in retail food refrigeration are
provided in the docket for this proposed rule (EPA-HQ-OAR-2023-0043) at
<a href="https://www.regulations.gov">https://www.regulations.gov</a>. EPA performed a risk screening assessment
to examine the health and environmental risks of this substitute. This
risk screen is available in the docket for this proposed rule.\21\
---------------------------------------------------------------------------

\21\ ICF, 2023h. Risk Screen on Substitutes in Retail Food
Refrigeration (New Equipment); Substitute: Propane (R-290).
---------------------------------------------------------------------------

Environmental information: R-290 has an ODP of zero. R-290 has a
GWP of three. R-290 is regulated as a VOC under CAA regulations (40 CFR
51.100(s)) addressing the development of SIPs to attain and maintain
the NAAQS. EPA previously exempted R-290 in retail food refrigerators
and freezers (stand-alone units only) from the prohibition under CAA
section 608(c)(2) on knowingly venting, releasing, or disposing of
substitute refrigerants, finding that such venting, release, or
disposal does not pose a threat to the environment (79 FR 29682, May
23, 2014).
EPA evaluated potential impacts of R-290 and other HC refrigerants
on local air quality. R-290 (propane) is considered a VOC and is not
excluded from EPA's regulatory definition of VOC (see 40 CFR 51.100(s))
addressing the development of SIPs to attain and maintain the NAAQS. As
described below, EPA estimates that potential emissions of saturated HC
refrigerants, such as R-290 and R-600a (isobutane), do not have a
significant impact on local air quality.\22\
---------------------------------------------------------------------------

\22\ ICF, 2014a. Assessment of the Potential Impact of
Hydrocarbon Refrigerants on Ground Level Ozone Concentrations.
February, 2014.
---------------------------------------------------------------------------

EPA has conducted multiple analyses of various scenarios to
consider the potential impacts on local air quality if HC refrigerants
were used widely.\23\ The analyses considered both worst-case and more
realistic scenarios. In an analysis supporting the listings of R-290,
R-600a, and the HC blend R-441A in multiple refrigeration and air
conditioning end-uses in SNAP Rule 19 (80 FR 19454, April 10, 2015),
the worst-case scenario assumed that the most reactive HC listed as
acceptable as of the time of those listings (R-600a) was used in all
refrigeration and AC uses and that all refrigerant used was emitted to
the atmosphere rather than most being recovered. In that extreme
scenario, the model predicted that the maximum increase in any single
8-hour average ground-level ozone concentration would be 0.72 parts per
billion (ppb) in Los Angeles, which is the area with the highest level
of ozone pollution in the United States. At the time of the analysis in
2014, 0.72 ppb was less than 1% of the NAAQS, and

[[Page 33733]]

we stated at the time that the use of R-600a consistent with the use
conditions required in EPA's regulations would not result in
significantly greater risk to the environment than other alternatives.
Using the current ozone NAAQS value of 70 ppb, use of the most reactive
saturated HC, R-600a, with a 100% market penetration would just exceed
a level that might raise concerns for EPA. However, considering that R-
290 is less reactive than R-600a \24\ and that R-290 would have a
market penetration at least as high as that of R-600a,\25\ we still
consider use of saturated HC refrigerants not to result in
significantly greater risk.
---------------------------------------------------------------------------

\23\ Ibid.
\24\ R-600a has a maximum incremental reactivity (MIR) of 1.34 g
O<INF>3</INF>/g R-600a, while R-290 has a MIR of 0.56 g
O<INF>3</INF>/g R-290. ICF, 2023h, Op. cit.; Carter, 2010.
``Development of the SAPRC-07 Chemical Mechanism and Updated Ozone
Reactivity Scales,'' Report to the California Air Resources Board by
William P.L. Carter. Revised January 27, 2010.
---------------------------------------------------------------------------

In a less conservative analysis of potential impacts on ambient
ozone levels, EPA looked at a set of end-uses that would be more likely
to use HC refrigerants between now and 2030, including end-uses where
they previously have been listed as acceptable and where they are
proposed to be acceptable under this rule. For example, we assumed use
of R-290 in refrigerated food processing and dispensing equipment \25\
and in end-uses where it is already listed as acceptable, including
retail food refrigeration--stand-alone units, vending machines, water
coolers, self-contained commercial ice machines, room air conditioners,
and household refrigerators and freezers. We also assumed the use of
other HC refrigerants such as R-600a and R-441A in end-uses where they
are listed as acceptable, such as in retail food refrigeration--stand-
alone units, vending machines, and household refrigerators and
freezers. For further information on the specific assumptions, see the
docket for this rulemaking.\26\ Based on this still conservative but
more probable assessment of refrigerant use, we found that even if all
the refrigerant in appliances in end-uses addressed in this proposed
rule and in appliances in end-uses for which other HCs are listed as
acceptable were to be emitted, there would be a worst-case impact of a
0.15 ppb increase in ozone for a single 8-hour average concentration in
the Los Angeles area, which is the area with the highest level of ozone
pollution in the United States. In the other cities examined in the
analysis, Houston and Atlanta, impacts were smaller (no more than 0.03
and 0.01 ppb for a single 8-hour average concentration,
respectively).\27\ For areas in the analysis that were not violating
the 2008 ozone NAAQS, the impacts did not cause an exceedance of the
2008 ozone NAAQS.
---------------------------------------------------------------------------

\25\ In the analysis, refrigerated food processing and
dispensing equipment was evaluated under the category of ``small
retail food'' refrigeration equipment, along with stand-alone units,
vending machines, and water coolers.
\26\ ICF, 2014a. Assessment of the Potential Impact of
Hydrocarbon Refrigerants on Ground Level Ozone Concentrations.
February 2014.
\27\ Ibid.
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EPA also has performed more recent air quality analyses,
considering additional end-uses and refrigerants that have been listed
acceptable more recently (e.g., R-1150 in very low temperature
refrigeration) and using updated models.\28\ EPA found that the revised
air quality models showed slightly greater impacts compared to our 2014
analyses in all scenarios, but not enough to change our earlier
conclusions in 2015 and 2016 that use of saturated HCs as refrigerants,
including release of R-290, R-600a, and R-441A during repairing,
maintaining, servicing, or disposing of appliances, would not result in
a significant increase in ground-level ozone. Further, there would be
no change in the prior conclusion that use of the saturated HCs R-290,
R-600a, and R-441A, consistent with the SNAP listings, including their
use conditions and the proposed use conditions in this rule, would not
result in significantly greater risk to people's health or the
environment than other alternatives available for the same end-use,
refrigerated food processing and dispensing equipment.
---------------------------------------------------------------------------

\28\ ICF, 2020. Additional Assessment of the Potential Impact of
Hydrocarbon Refrigerants on Ground Level Ozone Concentrations. May
2020. Updated models included VM IO file_v5.1_10.01.19 and CMAQ
5.2.1 with carbon bond 06 (CB06) mechanism, as cited in ICF, 2020.
---------------------------------------------------------------------------

Based on the results of these analyses, EPA is proposing to list R-
290 as acceptable, subject to use conditions, in refrigerated food
processing and dispensing equipment. Because of the relatively minimal
air quality impacts of R-290 if it is released to the atmosphere from
the end-uses where it is listed as acceptable subject to use conditions
and from the proposed refrigerated processing and dispensing equipment
end-use category, even in a worst-case scenario, we conclude that R-290
does not have a significantly greater overall impact on human health
and the environment based on its effects on local air quality than
other refrigerants listed as acceptable in the same end-uses.
Flammability information: R-290 is a higher flammability
refrigerant, with an ASHRAE safety classification of A3. However, the
proposed substitute is not expected to present a flammability concern
provided the proposed use conditions are followed.
Toxicity and exposure data: R-290 has an ASHRAE toxicity
classification of A (lower toxicity). Potential health effects of
exposure to this substitute include drowsiness or dizziness. The
substitute may also irritate the skin or eyes or cause frostbite. This
substitute could cause asphyxiation if air is displaced by vapors in a
confined space. These potential health effects are common to many
refrigerants.
OSHA has established a PEL of 1,000 ppm as an 8-hr TWA for propane
(R-290). EPA anticipates that users will be able to meet OSHA's PEL and
address potential health risks by following requirements and
recommendations in the manufacturers' SDSs, the use conditions proposed
(including compliance with UL 60335-2-89), adherence to ASHRAE 15-2022,
and other safety precautions common to the refrigeration and AC
industry.
Comparison to other substitutes in the refrigerated food processing
and dispensing end-use category: R-290 has an ODP of zero, comparable
to or lower than some of the acceptable substitutes in new refrigerated
food processing and dispensing equipment, such as CO<INF>2,</INF> R-
450A, and R-513A, with ODPs of zero.
R-290's GWP of 3 is comparable to that of other acceptable
substitutes for new refrigerated food processing and dispensing
equipment, including CO<INF>2</INF>, with a GWP of 1. The GWP of R-290
is lower than some of the acceptable substitutes for new refrigerated
food processing and dispensing equipment, such as R-450A, R-513A, R-
134a, and R-407H, with GWPs of approximately 600, 630, 1,430, and
1,500, respectively.
EPA's risk screen for R-290 in retail food refrigeration,\29\
including refrigerated food processing and dispensing equipment, found
that R-290 can be used without exceeding its PEL of 1,000 ppm (8-hr
TWA); thus, the toxicity risks of R-290 are comparable to those of
other acceptable substitutes in the refrigerated food processing and
dispensing equipment end-use category, which also are used without
exceeding their workplace exposure limits.
---------------------------------------------------------------------------

\29\ ICF, 2023h. Op. cit.
---------------------------------------------------------------------------

Although we noted that the flammability of R-290 may be greater
than that of other available, substitutes with an ASHRAE 1, 2, or 2L
flammability classification in the same end-use, we found its
flammability risk to be not significant even under worst-case
assumptions in this end-use category when following the proposed

[[Page 33734]]

use conditions.\30\ We note that flammability risk can be minimized by
use consistent with industry standards such as UL 60335-2-89--which
would be required by our proposed use conditions--and ASHRAE 15-2022,
as well as recommendations in the manufacturers' SDS and other safety
precautions common in the refrigeration and air conditioning industry.
The proposed use conditions for refrigerated food processing and
dispensing equipment would maintain low potential risk associated with
the flammability of this alternative so that it will not pose
significantly greater risk than other acceptable substitutes in this
end-use category.
---------------------------------------------------------------------------

\30\ ICF, 2023h. Op. cit.
---------------------------------------------------------------------------

The proposed substitute, R-290, has a GWP of 3, lower than that of
most other available alternatives for the same end-use category with
similarly low toxicity. R-290 provides an additional lower-GWP option
for situations where other refrigerants with lower GWPs are not viable,
such as where equipment using CO<INF>2</INF> may not be able to meet
DOE's energy conservation standards. To provide additional, lower-GWP
options with lower overall risk to human health and the environment,
EPA is proposing the listing of R-290 as acceptable, subject to use
conditions, for use in refrigerated food processing and dispensing
equipment.
4. Why is EPA proposing these specific use conditions for refrigerated
food processing and dispensing equipment?
For refrigerated food processing and dispensing equipment, EPA
proposes to require use of UL 60335-2-89, for purposes of the SNAP
program, as of the effective date of the final rule based on this
proposal. Several of the use conditions proposed for refrigerated food
processing and dispensing equipment are common to those proposed for R-
290 in the commercial ice machine end-use in section II.D, and others
are common to all five end-uses in this proposed rule. Because of this
similarity, EPA discusses the use conditions that would apply to all
five end-uses in section II.H. In summary, the common use conditions
proposed include the following: restricting the use of each refrigerant
to new equipment that is specifically designed for that refrigerant;
use consistent with the 2nd edition of UL 60335-2-89, including
testing, charge sizes, ventilation, usage space requirements, and
certain hazard warnings and markings; and requirements for warning
labels and markings on equipment to inform consumers, technicians, and
first responders of potential flammability hazards.
5. How would the proposed listing for R-290 in refrigerated food
processing and dispensing equipment relate to regulations implementing
the venting prohibition under CAA section 608?
In section II.I of this document, EPA is proposing to exempt R-290
used as a refrigerant in refrigerated food processing and dispensing
equipment from the prohibition under CAA section 608(c)(2) on knowingly
venting or otherwise knowingly releasing or disposing of any substitute
refrigerant in the course of maintaining, servicing, repairing, or
disposing of an appliance or industrial process refrigeration.
6. What use conditions currently apply to this refrigerant in the
stand-alone units end-use category?
EPA previously listed R-290 acceptable, subject to use conditions,
in new stand-alone units in SNAP Rule 17 (76 FR 78832, December 20,
2011). Those requirements are codified in appendix R to 40 CFR part 82,
subpart G. EPA provided information on the potential environmental and
health risks of R-290 and the various substitutes available at that
time for use in this end-use category. Additionally, EPA's previous
risk screen for this refrigerant in this end-use category, based on the
use conditions in that rule, is available in the docket for that
previous rulemaking (EPA-HQ-OAR-2009-0286).
R-290 has an ASHRAE classification of A3, indicating that it has
low toxicity and higher flammability. In the presence of an ignition
source (e.g., static electricity, a spark resulting from a closing
door, or a cigarette), an explosion or a fire could occur if the
concentration of R-290 were to exceed the LFL of 21,000 ppm (2.1
percent) by volume.
The use conditions established in the 2011 listing for R-290 in new
stand-alone units addressed safe use of this flammable refrigerant
based on information available at that time and included the following:
incorporation by reference of Supplement SB to the 10th edition
(November 24, 2010) of the standard UL 471 ``Commercial Refrigerators
and Freezers''; refrigerant charge size limits based on cooling
capacity and type of equipment; and requirements for markings and
warning labels on equipment using the refrigerant to inform consumers,
technicians, and first responders of potential flammability hazards.
EPA explained in that rulemaking that without appropriate use
conditions, the flammability risk posed by this refrigerant could be
higher than non-flammable refrigerants because individuals may not be
aware that their actions could potentially cause a fire, and because
the refrigerant could be used in existing equipment that has not been
designed specifically to minimize flammability risks. Our assessment
and listing decisions in SNAP Rule 17 (76 FR 78832, December 20, 2011)
found that with the use conditions, the overall risk of R-290,
including the risk due to flammability, was not significantly greater
in the stand-alone units end-use than other substitutes that are
currently or potentially available for that same end-use.
7. What updates to existing use conditions for stand-alone units is EPA
proposing?
EPA is proposing to update the use conditions that apply to R-290
in new stand-alone units manufactured on or after the effective date of
any final rule based on this proposal. Several of the updated use
conditions proposed for use of R-290 in stand-alone units are common to
those proposed for the commercial ice machine end-use in section II.D,
and others are common to all five end-uses in this proposed rule.
Because of this similarity, EPA discusses the use conditions that would
apply to all five end-uses in section II.H. For R-290 in stand-alone
units, these are the only revised use conditions EPA is proposing. In
summary, with the updates proposed to the use conditions for stand-
alone units, the common use conditions proposed include the following:
restricting the use of each refrigerant to new equipment that is
specifically designed for that refrigerant; use consistent with the 2nd
edition of UL 60335-2-89, including testing, charge sizes, ventilation,
usage space requirements, and certain hazard warnings and markings; and
requirements for warning labels and markings on equipment to inform
consumers, technicians, and first responders of potential flammability
hazards.
If finalized as proposed, the use conditions in this action would
apply to new stand-alone units on or after the effective date of any
final rule. Any final rule would not apply to nor affect equipment
manufactured before the effective date of this action and manufactured
in compliance with the SNAP use conditions applicable at the time of
manufacture as stipulated in SNAP Rule 17 and appendix R to 40 CFR part
82, subpart G. EPA views equipment to be manufactured at the date upon
which the appliance's

[[Page 33735]]

refrigerant circuit is complete, the appliance can function, the
appliance holds a full refrigerant charge, and the appliance is ready
for use for its intended purposes. For stand-alone units (and most
refrigerated food processing and dispensing equipment), this occurs at
the factory. If this rule is finalized as proposed, new stand-alone
units manufactured between February 21, 2012, and the effective date of
the final rule would be required to meet the use conditions in SNAP
Rule 17 (which took effect February 21, 2012) and as listed in appendix
R to 40 CFR part 82, subpart G, including the use condition
incorporating by reference Supplement SB to the 10th edition of UL 471.
Such products would be permitted to be warehoused and sold through
normal channels, even if they are sold or installed after the effective
date of any final rule based on this proposed rule. Stand-alone units
using R-290 manufactured on or after the effective date of any final
rule based on this proposal would be required to meet the use
conditions so finalized and listed in the revisions to appendix R.
Those use conditions would allow manufacturers of new stand-alone units
using R-290 to follow either UL 471 or UL 60335-2-89 from the effective
date of any final rule based on this proposal and would last through
September 29, 2024. On and after September 30, 2024, the use condition
for use of R-290 in equipment that meets UL 60335-2-89 only would apply
under SNAP.
EPA is proposing use conditions allowing new stand-alone units to
be manufactured consistent with Supplement SB of UL 471, up to and
including September 29, 2024, which is the date when UL is sunsetting
UL 471. Therefore, during the time between the effective date of any
final rule based on this proposal and September 29, 2024, manufacturers
would be allowed to follow either UL 471, 10th Edition or UL 60335-2-
89, 2nd Edition. EPA is proposing allowing manufacturers to adhere to
either standard for this limited time because the Agency recognizes
that manufacturers may need time to make necessary changes including to
their product labels. The period during which manufacturers may follow
either standard should provide sufficient time for manufacturers to
transition from UL 471 to UL 60335-2-89. EPA proposes that, beginning
September 30, 2024, R-290 may only be used in new stand-alone units
that meet all requirements in UL 60335-2-89 for the purposes of the
SNAP program. See section II.H.1 for further discussion on the
requirements of this standard that EPA is proposing to incorporate by
reference.
In addition, we are proposing that manufacturers would need to
follow the set of use conditions that correspond with a specific UL
standard (i.e., when using UL 471, follow all use conditions in listing
2 and when using UL 60335-2-89, follow all use conditions in listing 4
in the proposed revisions to appendix R). After the transition period
ends, stand-alone units manufactured with R-290 would need to follow UL
60335-2-89 for purposes of the SNAP program.
EPA also notes that we are not proposing to change two use
conditions that currently apply, nor are we taking comment on those
other use conditions. The use conditions that restrict the use of R-290
to new equipment specifically designed for this refrigerant, and that
require red-colored markings on service ports, pipes, hoses, and other
devices through which the refrigerant is serviced, repeat the current
use conditions for R-290 in new stand-alone units. If the regulatory
text is finalized as proposed, EPA would amend to add use conditions
that apply to R-290 in new stand-alone units manufactured on or after
the effective date of the final rule. Equipment manufactured before the
effective date of the final rule would not be affected by this action
and would hence be subject to the current use conditions included in
appendix R.
8. How do the proposed use conditions for stand-alone units differ from
the existing ones and why is EPA proposing to change the use
conditions?
The revised use conditions EPA is proposing for stand-alone units
are similar to the ones that exist today in appendix R to 40 CFR part
82, subpart G, for R-290 in this end-use category. The requirements
that R-290 must be used in new equipment only, and that new stand-alone
units must include red markings at service ports, pipes, hoses, and
other devices through which the refrigerant is serviced, are repeated
in this proposed listing. The updated use conditions concern
incorporating by reference the most recent U.S. national standard and
updated labeling requirements consistent with that new standard. Stand-
alone units using R-290 manufactured before the effective date of a
final rule to this proposal would not be affected by the updated use
conditions.
Warning labels are required under EPA's current regulations, and
EPA is proposing to continue to require them, although with some
specific language changes. The proposed warning labels are similar to
those required currently as use conditions for the use of R-290 in
stand-alone units. EPA finds that using a common set of labels, similar
to those from UL 60335-2-89, would aid in compliance and could reduce
burden for the industry, especially for a manufacturer that uses more
than one refrigerant. EPA is proposing that the labels must be provided
in letters no less than 6.4 millimeter (\1/4\ inch) high and must be
permanent, which is identical to the current requirement for R-290 in
stand-alone units.
EPA is proposing to incorporate by reference a new industry
standard in the use conditions, including use of the 2nd edition of UL
60335-2-89 instead of continuing to require the standard Supplement SB
of the 10th edition of UL 471 for equipment manufactured on or after
the effective date of any final rule based on this proposal. UL 60335-
2-89 was developed in an open and consensus-based approach, with the
assistance of experts in the refrigeration and AC industry as well as
experts involved in assessing the safety of products. The revision
cycle for the 2nd edition, including final recirculation, concluded
with its publication on October 27, 2021. The 2nd edition of UL 60335-
2-89 replaces the previously published version of several standards,
including UL 471, which had already been published as a 10th edition by
that time. EPA was aware of the continuing progress of UL standards to
address flammable refrigerants more appropriately. In SNAP Rule 23 (86
FR 24444, May 6, 2021), which listed a number of A2L refrigerants for
use in the residential and light commercial AC and heat pumps (HPs)
end-use, we stated, ``EPA understands that the standard we relied on in
[SNAP] Rule 19 might `sunset' in the future. Therefore, we will
continue to evaluate the market for the equipment addressed in that
rule, including R-290 in stand-alone units, and whether to establish
new or revised use conditions that reference UL 60335-2-89.'' In this
document, we are proposing such a change knowing that UL is replacing
the standard to which such equipment is certified from UL 471 to the
newer standard UL 60335-2-89 starting September 30, 2024.
To allow time for manufacturers of stand-alone units to transition
between the current use condition using the 10th edition of UL 471, and
the new use condition using the 2nd edition of UL 60335-2-89, EPA is
proposing to allow R-290 to be used in stand-alone units manufactured
either following UL 471 or UL 60335-2-89 during a transition period. We
propose that transition period would begin on the effective date of the
final rule based on this proposal

[[Page 33736]]

and would last through September 29, 2024. It is EPA's understanding
that UL intends to sunset UL 471 on September 29, 2024, and EPA is
proposing to coordinate with that sunset date. Beginning September 30,
2024, the use condition in effect would only allow R-290 to be used in
new stand-alone units that follow UL 60335-2-89. In addition, we are
proposing that manufacturers would need to follow the set of use
conditions that correspond with a specific UL standard (i.e., when
using UL 471, follow all use conditions in listing 4 and when using UL
60335-2-89, follow all use conditions in listing 6 in the proposed
revisions to appendix R).
Updating the UL standard incorporated as a use condition will
provide more consistency amongst the products within the retail food
refrigeration end-use. This change will allow the industry to focus on
the most recent standard. The change will be helpful in implementing
any transitions needed or planned for manufacturers, installers, and
technicians. A manufacturer, who may offer different products within
this end-use with different refrigerants, could use similar processes,
such as in developing and applying the warning labels required.
Installers and technicians, likewise, would not need to reference
different standards depending on the type of equipment and the
particular flammable refrigerant being used in that equipment, when
putting in a new piece of equipment or servicing that equipment.
Another proposed revision to the use conditions is the limit on
charge sizes. The current use conditions from SNAP Rule 17 require the
charge sizes calculated consistent with UL 471, with a maximum charge
of 150 g allowed. The proposed revised use conditions for equipment
manufactured on or after the effective date of any final rule would
allow charge sizes calculated based on UL 60335-2-89, which allows
charges of up to 500 g of R-290 for open stand-alone units, or 300 g
for those with doors and drawers.
Because of the differences between UL 471 and UL 60335-2-89, EPA
performed a new risk screen for R-290 as a refrigerant in retail food
refrigeration equipment, including stand-alone units.\31\ In this risk
screen, EPA adjusted charge sizes to be consistent with the larger
charge sizes of 300 g and 500 g allowed for R-290 under UL 60335-2-89.
The risk screen also considered the impact of mitigation methods such
as valves that would restrict the amount of refrigerant that could be
released. The updated risk screen found that concentrations of R-290
still would not exceed the LFL when used according to the proposed use
condition and consistent with UL 60335-2-89, and thus the proposed new
use conditions would also address potential flammability risks of using
R-290.\32\ In addition, the risk screen modeled the reasonable work
case scenario of short-term exposure (15-minute TWA) due to a
catastrophic release of the charge. Under this highly conservative
scenario, the worst-case exposure of 5,770 ppm was still significantly
lower than the Acute Toxicity Exposure Limit (ATEL) of 50,000 ppm.\33\
For further information, see the risk screen in the docket for this
rulemaking.
---------------------------------------------------------------------------

\31\ ICF, 2023h. Op. cit.
\32\ Ibid.
\33\ The source of the ATEL is ASHRAE 34-2022, as cited in ICF,
2023h. Op cit.
---------------------------------------------------------------------------

9. What additional information is EPA including in these proposed
listings?
EPA is providing additional information related to the proposed
listing for R-290 in new refrigerated food processing and dispensing
equipment and the proposed revised listing for R-290 in new stand-alone
units. Since this additional information is not part of the regulatory
decision under SNAP, these statements are not binding for use of the
substitute under the SNAP program. See section II.H.2 for further
discussion on what additional information EPA is including in these
proposed listings. EPA notes that the additional information is similar
to, but not identical with, the addition information in the listing for
R-290 in stand-alone units in SNAP Rule 17. EPA is proposing additional
information consistent with that included in the other proposed
listings for stand-alone units in this rule and consistent with that
included in the listings for R-290 as acceptable, subject to use
conditions, in stand-alone units in Rule 17. While the items listed are
not legally binding under the SNAP program, EPA encourages users of
substitutes to apply all statements in the ``Further Information''
column in their use of these substitutes.
10. On which topics is EPA specifically requesting comment?
EPA is requesting comment on all aspects of the proposed decision
to list R-290 acceptable, subject to use conditions, in new
refrigerated food processing and dispensing equipment as discussed in
this section II.B. EPA also requests comments on the proposed change in
use conditions for use of R-290 in stand-alone units, and if and how
such change would affect the safety of stand-alone units using R-290.
The Agency requests comment on the time periods during which
manufacturers are to follow UL 471, either UL 471 or UL 60335-3-89, or
only UL 60335-2-89. EPA also requests comments on the proposed use
conditions for use of R-290 in new refrigerated food processing and
dispensing equipment, including the proposed requirements to comply
with UL 60335-2-89. With respect to this standard, EPA is requesting
comment on the risk mitigation offered by compliance with the current
version of the standard proposed as use conditions, i.e., UL 60335-2-
89, the nature of updates proposed for this standard, and the expected
timeline for those updates. EPA is requesting comment on the
applicability of the 2nd edition of UL 60335-2-89 to refrigerated food
processing and dispensing equipment, including which types of
equipment, under which applications the standard applies, and whether
the listing of R-290 should apply to refrigerated food processing and
dispensing equipment that has a remote compressor and is not self-
contained.

C. Commercial Ice Machines--Proposed Listing of HFC-32, HFO-1234yf, R-
454A, R-454B, R-454C, R-455A, R-457A, and R-516A as Acceptable, Subject
to Use Conditions, for Use in New Commercial Ice Machines

EPA is proposing to list HFC-32, HFO-1234yf, and the refrigerant
blends R-454A, R-454B, R-454C, R-455A, R-457A, and R-516A as
acceptable, subject to use conditions, for use in new commercial ice
machines.
Several use conditions proposed for commercial ice machines are
common to those proposed for other end-uses. Because of this
similarity, EPA discusses the use conditions that would apply to all
five end-uses in section II.H. For commercial ice machines, those are
the only use conditions EPA is proposing. In summary, the common use
conditions proposed include the following: restricting the use of each
refrigerant to new equipment that is specifically designed for that
refrigerant; use consistent with the 2nd edition of UL 60335-2-89,
including testing, charge sizes, ventilation, usage space requirements,
and certain hazard warnings and markings; and requirements for warning
labels and markings on equipment to inform consumers, technicians, and
first responders of potential flammability hazards.

[[Page 33737]]

If the regulatory text is finalized as proposed, EPA would revise
the existing listing for R-290 in new self-contained commercial ice
machines in appendix V to 40 CFR part 82, subpart G. The proposed
regulatory text contains listing decisions for the commercial ice
machines end-use, as well as certain other previous listings that EPA
is republishing for purposes of formatting for the Federal Register;
EPA is not proposing substantive changes to, and is not taking comment
on, those earlier decisions (i.e., listings for R-290 in new water
coolers and in new very low temperature refrigeration equipment).
1. Background on Commercial Ice Machines
Commercial ice machines are used in commercial establishments
(e.g., hotels, restaurants, convenience stores) to produce ice for
consumer use. Commercial ice machines \34\ are another subset of
commercial refrigeration and are considered a separate end-use within
the SNAP program from retail food refrigeration due to differences in
where such equipment is placed and the additional mechanical and
electronic components required to make and dispense ice. Ice machines
produce ice in various sizes and shapes, and with different retrieval
mechanisms (e.g., dispensers or self-retrieval from bins). Many
commercial ice machines are self-contained units, while some have the
condenser separated from the portion of the machine making the ice and
have refrigerated lines running between the two (also known as remote
equipment). Commercial ice machines fall under the scope of UL 60335-2-
89, ``Household and Similar Electrical Appliances--Safety--Part 2-89:
Requirements for Commercial Refrigerating Appliances and Ice-Makers
with an Incorporated or Remote Refrigerant Unit or Motor-Compressor.''
---------------------------------------------------------------------------

\34\ Industry standards for this type of equipment, e.g., UL 563
and UL 60335-2-89, use the terms ``ice maker'' or ``ice-maker''
rather than commercial ice machines. The terms may be used
interchangeably and refer to the same equipment.
---------------------------------------------------------------------------

This proposal, if finalized, would list HFC-32, HFO-1234yf, R-454A,
R-454B, R-454C, R-455A, R-457A, and R-516A as acceptable, subject to
use conditions, in new commercial ice machines.
2. What are the ASHRAE classifications for refrigerant flammability?
ASHRAE 34-2022 categorizes the refrigerants proposed for commercial
ice machines in this section as being in the A2L Safety Group. See
section II.A.2 for further discussion on ASHRAE classifications of
these refrigerants.
3. What are HFC-32, HFO-1234yf, R-454A, R-454B, R-454C, R-455A, R-457A,
and R-516A and how do they compare to other refrigerants in the same
end-use?
See section II.A.3 for further discussion on the environmental,
flammability, toxicity, and exposure information for HFC-32, HFO-
1234yf, R-454A, R-454B, R-454C, R-455A, R-457A, and R-516A.\35\
---------------------------------------------------------------------------

\35\ EPA previously listed HFO-1234yf as acceptable, subject to
use conditions, in motor vehicle AC in light-duty vehicles (74 FR
53445, October 19, 2009), in heavy-duty pickup trucks and complete
heavy-duty vans (81 FR 86778, December 1, 2016) and in nonroad
vehicles and service fittings for small refrigerant cans (87 FR
26276, May 4, 2022). EPA previously listed R-454A, R-454B, R-454C,
and R-457A as acceptable, subject to use conditions, as substitutes
in residential and light commercial AC and HPs (86 FR 24444, May 6,
2021). EPA previously listed HFC-32 as acceptable, subject to use
conditions, in self-contained room air conditioners (80 FR 19453,
April 10, 2015) and listed HFC-32 as acceptable, subject to use
conditions, in the remaining types of residential and light
commercial air conditioning and heat pumps.
---------------------------------------------------------------------------

HFC-32 is also known as R-32 or difluoromethane (CAS Reg. No. 75-
10-5). R-454B, also known by the trade names ``OpteonTM XL
41'' and ``Puron AdvanceTM,'' is a blend consisting of 68.9
percent HFC-32 and 31.1 percent HFO-1234yf. Redacted submissions and
supporting documentation for HFC-32, HFO-1234yf, and the refrigerant
blends are provided in the docket for this proposed rule (EPA-HQ-OAR-
2023-0043) at <a href="https://www.regulations.gov">https://www.regulations.gov</a>. EPA performed a risk
screening assessment to examine the health and environmental risks of
each of these substitutes. These risk screens are available in the
docket for this proposed rule.36 37 38
39 40 41 42 43
---------------------------------------------------------------------------

\36\ ICF, 2023i. Risk Screen on Substitutes in Commercial Ice
Machines (New Equipment); Substitute: HFC-32.
\37\ ICF, 2023j. Risk Screen on Substitutes in Commercial Ice
Machines (New Equipment); Substitute: HFO-1234yf.
\38\ ICF, 2023k. Risk Screen on Substitutes in Commercial Ice
Machines (New Equipment); Substitute: R-454A (Opteon[supreg] XL40).
\39\ ICF, 2023l. Risk Screen on Substitutes in Commercial Ice
Machines (New Equipment); Substitute: R-454B.
\40\ ICF, 2023m. Risk Screen on Substitutes in Commercial Ice
Machines (New Equipment); Substitute: R-454C (OpteonTM
XL20).
\41\ ICF, 2023n. Risk Screen on Substitutes in Commercial Ice
Machines (New Equipment); Substitute: R-455A (Solstice[supreg]
L40X).
\42\ ICF, 2023o. Risk Screen on Substitutes in Commercial Ice
Machines (New Equipment); Substitute: R-457A (Forane[supreg] 457A).
\43\ ICF, 2023p. Risk Screen on Substitutes in Commercial Ice
Machines (New Equipment); Substitute: R-516A (Forane[supreg] 516A).
---------------------------------------------------------------------------

Comparison to other substitutes in this end-use: HFC-32, HFO-
1234yf, and the refrigerant blends R-454A, R-454B, R-454C, R-455A, R-
457A, and R-516A all have an ODP of zero, comparable to or lower than
some of the acceptable substitutes in new commercial ice machines, such
as HFC-134a, R-410A, and R-513A, with ODPs of zero.
HFO-1234yf has a GWP of less than four, comparable to that of R-290
and ammonia with GWPs of 3 and zero. R-454A, R-454B, R-454C, R-455A, R-
457A, and R-516A have GWPs ranging from 140 to 470, higher than some of
the acceptable substitutes for new commercial ice machines, including
R-290 and ammonia with GWPs of 3 and zero, respectively, and lower than
those of other substitutes such as R-450A and R-513A, with GWPs of
about 600 and 630. HFC-32 has a GWP of 675, higher than some of the
acceptable substitutes including R-290, R-450A, and R-513A; however,
the GWP of HFC-32 is lower than those of R-410A and R-404A, with GWPs
of approximately 2,090 to 3,920, which are refrigerants that have
typically been employed in such systems. Our initial evaluation is that
the characteristics of HFC-32 meet the technical needs of larger
commercial ice machines, providing larger charge sizes, greater
capacity and no glide, allowing for even formation of ice, while lower-
GWP alternatives do not. For instance, R-513A and R-450A have lower
capacity than HFC-32, and R-290 is restricted to smaller charge sizes
(see section II.D for further information). Remote appliances using A2L
refrigerants, including remote condensers, may be either self-contained
or field erected and may be factory or field charged.
Information regarding the toxicity of other available alternatives
is provided in the previous listing decisions for new commercial ice
machines (<a href="https://www.epa.gov/snap/substitutes-commercial-ice-machines">https://www.epa.gov/snap/substitutes-commercial-ice-machines</a>). Toxicity risks of use, determined by the likelihood of
exceeding the exposure limit of HFC-32, HFO-1234yf, and the refrigerant
blends in these end-uses are evaluated in the risk screens referenced
previously. The toxicity risks of using HFC-32, HFO-1234yf, and the
refrigerant blends in new commercial ice machines are comparable to or
lower than toxicity risks of other available substitutes in the same
end-use. Toxicity risks of the proposed refrigerants can be mitigated
by use consistent with UL 60335-2-89, ASHRAE 15-2022, and other
industry standards; recommendations in the manufacturers' SDS; and
other safety precautions common in the refrigeration and AC industry.
The flammability risks of HFC-32, HFO-1234yf, and the refrigerant
blends R-454A, R-454B, R-454C, R-455A, R-

[[Page 33738]]

457A, and R-516A in the new commercial ice machine end-use, determined
by the likelihood of exceeding their respective lower flammability
limits, are evaluated in the risk screens referenced previously in this
section. While these refrigerants may pose greater flammability risk
than other available, non-flammable substitutes in the new commercial
ice machines end-use, this risk can be mitigated by use consistent with
ASHRAE 15-2022 and UL 60335-2-89, required by our proposed use
conditions, as well as recommendations in the manufacturers' SDS and
other safety precautions common in the refrigeration and AC industry.
EPA is proposing use conditions to reduce the potential risk associated
with the flammability of these alternatives so that they will not pose
significantly greater risk than other acceptable substitutes in the new
commercial ice machines end-use.
In addition, the proposed substitutes have lower GWPs than most
other available alternatives for new commercial ice machines. The
proposed refrigerants provide additional lower-GWP options for
situations where other refrigerants with lower GWPs are not viable,
such as for use of HCs in systems with remote compressors or equipment
requiring larger charge sizes, where equipment using CO<INF>2</INF> may
not be able to meet energy conservation standards from the DOE, or
where a refrigerant must have minimal glide to ensure consistent
freezing while manufacturing ice. Given the wide range of applications
and exacting performance requirements for commercial ice machines, not
all refrigerants listed as acceptable under SNAP will be suitable for
the range of equipment in new commercial ice machines. To provide
additional options to ensure the availability of substitutes with lower
GWP for the full range of new commercial ice machines and, therefore,
lower overall risk to human health and the environment, EPA is
proposing the listings for HFC-32, HFO-1234yf, and the refrigerant
blends R-454A, R-454B, R-454C, R-455A, R-457A, and R-516A as
acceptable, subject to use conditions, for use in new commercial ice
machines.
4. Why is EPA proposing these specific use conditions?
EPA is proposing to list HFC-32, HFO-1234yf, and the refrigerant
blends R-454A, R-454B, R-454C, R-455A, R-457A, and R-516A as
acceptable, subject to use conditions, for use in new commercial ice
machines. The use conditions identified in these proposed listings are
explained in section II.H.1 in greater detail.
5. What additional information is EPA including in these proposed
listings?
EPA is providing additional information related to these proposed
listings. Since this additional information is not part of the
regulatory decision under SNAP, these statements are not binding for
use of the substitute under the SNAP program. See section II.H.2 for
further discussion on what additional information EPA is including in
these proposed listings. While the items listed are not legally binding
under the SNAP program, EPA encourages users of substitutes to apply
all statements in the ``Further Information'' column in their use of
these substitutes.
6. On which topics is EPA specifically requesting comment?
EPA is requesting comment on all aspects of the proposed decision
to list HFC-32, HFO-1234yf, and R-454A, R-454B, R-454C, R-455A, R-457A,
and R-516A acceptable, subject to use conditions, in new commercial ice
machines as discussed in this section II.C. EPA seeks comment on the
risk mitigation offered by the proposed use conditions, including
requiring compliance with UL 60335-2-89, except to the extent the
proposed rule conflicts with the UL Standard, in which case we propose
that the use conditions specified in the rule would apply. We also
request comment on whether EPA should consider other use conditions to
further mitigate potential risk from the proposed refrigerants in this
end-use. EPA requests comment on whether commercial ice machines have
been designed for or manufactured with the refrigerants proposed and
any information on the safety of such equipment in other countries, and
if and how such experience would translate to safe use in the United
States.

D. Commercial Ice Machines--Proposed Revision of Use Conditions in the
Previous Listing of R-290 as Acceptable, Subject to Use Conditions, for
Use in New Self-Contained Commercial Ice Machines

EPA is proposing to revise use conditions in the previous listing
of R-290 as acceptable, subject to use conditions, for use in new self-
contained commercial ice machines. More specifically, EPA previously
listed R-290 as acceptable, subject to use conditions, in new self-
contained commercial ice machines in SNAP Rule 21 (81 FR 86779,
December 1, 2016). In this document, we are proposing to update those
use conditions to be consistent with the most recent U.S. national
standard for commercial refrigeration equipment, including commercial
ice machines, the 2nd edition of UL 60335-2-89. Similar use conditions
would apply to other refrigerants with lower flammability as proposed
in this SNAP action in section II.C above. The proposed revised use
conditions would be allowed for such equipment manufactured on or after
the effective date of any final rule and would not apply to nor affect
equipment manufactured before the effective date of any final action
and manufactured in compliance with the SNAP requirements applicable at
the time of manufacture.
This proposed revision to the use conditions would incorporate by
reference a different industry standard, changing the reference from
Supplement SA to the 8th edition, dated July 31, 2009, of the standard
UL 563, ``Ice Makers'' to the 2nd edition of UL 60335-2-89. EPA is
proposing a transition period during which self-contained commercial
ice machines manufactured with R-290 may follow either the earlier
standard UL 563 or UL 60335-2-89. After the transition period ends,
self-contained commercial ice machines manufactured with R-290 would
need to follow UL 60335-2-89 for purposes of the SNAP program.
Several use conditions proposed for this end-use are similar to
those proposed for other end-uses. Because of this similarity, EPA
discusses the use conditions that would apply to all five end-uses in
section II.H. In summary, the common use conditions proposed include
the following: restricting the use of the refrigerant to new equipment
that is specifically designed for that refrigerant; use consistent with
the 2nd edition of UL 60335-2-89, including testing, charge sizes,
ventilation, usage space requirements, and certain hazard warnings and
markings; and requirements for warning labels and markings on equipment
to inform consumers, technicians, and first responders of potential
flammability hazards. The regulatory text of the proposed decisions
appears in tables at the end of this document.
If the regulatory text is finalized as proposed, EPA would revise
the existing listing for R-290 in new self-contained commercial ice
machines in appendix V to 40 CFR part 82, subpart G. The proposed
regulatory text contains listing decisions for new self-contained
commercial ice machines in appendix V, as well as certain other
previous listings that EPA is republishing for purposes of formatting
for the Federal

[[Page 33739]]

Register; EPA is not proposing substantive changes to, and is not
taking comment on, those earlier decisions (i.e., listings for R-290 in
new water coolers and in new very low temperature refrigeration
equipment).
1. Background on commercial ice machines
See section II.C.1 for background on this end-use.
2. What are the ASHRAE classifications for refrigerant flammability?
ASHRAE 34-2022 categorizes R-290 as being in the A3 Safety Group.
See section II.A.2 for further discussion on ASHRAE classifications.
3. What is R-290 and were is there information on its use in this end-
use?
See section II.B.3 for further discussion on the identity,
environmental, flammability, toxicity, and exposure information for R-
290.
Redacted submissions and supporting documentation for R-290 are
provided in the docket for this proposed rule (EPA-HQ-OAR-2023-0043) at
<a href="https://www.regulations.gov">https://www.regulations.gov</a>. EPA performed a risk screening assessment
to examine the health and environmental risks of this substitute in
self-contained commercial ice machines. The risk screen is available in
the docket for this proposed rule.\44\
---------------------------------------------------------------------------

\44\ ICF, 2023q. Risk Screen on Substitutes in Commercial Ice
Machines (New Equipment); Substitute: (R-290).
---------------------------------------------------------------------------

4. What use conditions currently apply to this refrigerant in this end-
use?
EPA previously listed R-290 acceptable, subject to use conditions,
in new self-contained commercial ice machines in SNAP Rule 21 (81 FR
86779, December 1, 2016). Those requirements are codified in appendix V
to 40 CFR part 82, subpart G. EPA provided information on the
environmental and health risks of R-290 and the various substitutes
available at that time for use in this end-use. Additionally, EPA's
previous risk screen for this refrigerant, based on the use conditions
in that rule, is available in the docket for that previous rulemaking
(EPA-HQ-OAR-2015-0663).
R-290 has an ASHRAE classification of A3, indicating that it has
low toxicity and higher flammability. In the presence of an ignition
source (e.g., static electricity, a spark resulting from a closing
door, or a cigarette), an explosion or a fire could occur if the
concentration of R-290 were to exceed the LFL of 21,000 ppm (2.1
percent) by volume.
The use conditions established in the 2016 listing for R-290 in new
self-contained commercial ice machines addressed safe use of this
flammable refrigerant and included the following: incorporation by
reference of Supplement SA to the 8th edition (July 31, 2009, including
revisions through November 29, 2013) of the standard UL 563, ``Ice
Makers''; refrigerant charge size limits based on cooling capacity and
type of equipment; and requirements for markings and warning labels on
equipment using the refrigerant to inform consumers, technicians, and
first responders of potential flammability hazards. Our assessment and
listing decisions in SNAP Rule 21 (81 FR 86779, December 1, 2016) found
that with the use conditions, the overall risk of this substitute,
including the risk due to flammability, was not significantly greater
risk in this end-use than other substitutes that are currently or
potentially available for that same end-use.
5. What updates to the existing use conditions for commercial ice
machines is EPA proposing?
EPA is proposing to update the use conditions that apply to R-290
in new self-contained commercial ice machines manufactured on or after
the effective date of any final rule based on this proposal. Several of
the updated use conditions proposed for use of R-290 in self-contained
commercial ice machines are common to those proposed for the stand-
alone units end-use in section II.B, and other are common to all five
end-uses in this proposed rule. Because of this similarity, EPA
discusses the use conditions that would apply to all five end-uses in
section II.H. For R-290 in self-contained commercial ice machines,
these are the only revised use conditions EPA is proposing. In summary,
with the updates proposed to the use conditions for new self-contained
commercial ice machines, the common use conditions proposed include the
following: restricting the use of the refrigerant to new equipment that
is specifically designed for that refrigerant; use consistent with the
2nd edition of UL 60335-2-89, including testing, charge sizes,
ventilation, usage space requirements, and certain hazard warnings and
markings; and requirements for warning labels and markings on equipment
to inform consumers, technicians, and first responders of potential
flammability hazards.
If finalized as proposed, the use conditions in this action would
apply to new self-contained commercial ice machines manufactured on or
after the effective date of the final rule. Any final rule would not
apply to nor affect equipment manufactured before the effective date of
this action and manufactured in compliance with the SNAP use conditions
applicable at the time of manufacture as stipulated in SNAP Rule 21 and
appendix V to 40 CFR part 82, subpart G. EPA views equipment to be
manufactured at the date upon which the appliance's refrigerant circuit
is complete, the appliance can function, the appliance holds a full
refrigerant charge, and the appliance is ready for use for its intended
purposes. For new self-contained commercial ice machines, this occurs
at the factory. If this rule is finalized as proposed, new self-
contained commercial ice machines manufactured between January 3, 2017,
and the effective date of the final rule based on this proposal would
be required to meet the use conditions in SNAP Rule 21 (which took
effect January 3, 2017) and as listed in appendix V to 40 CFR part 82,
subpart G (in listing 1), including the use condition incorporating by
reference Supplement SA to the 8th edition of UL 563. Such products
would be permitted to be warehoused and sold through normal channels,
even if they are sold or installed after the effective date of any
final rule based on this proposed rule. Self-contained ice machines
using R-290 manufactured on or after the effective date of any final
rule based on this proposal through September 29, 2024, would be
required to meet the use conditions so finalized and listed in the
revisions to appendix V. Those use conditions would allow manufacturers
of new self-contained commercial ice machines using R-290 to follow
either UL 563 or UL 60335-2-89 from the effective date of any final
rule based on this proposal and would last through September 29, 2024.
On and after September 30, 2024, the use condition for use of R-290 in
equipment that meets UL 60335-2-89 only would apply under SNAP.
EPA is proposing use conditions allowing new self-contained
commercial ice machines to be manufactured consistent with Supplement
SA of UL 563, up to and including September 29, 2024, which is the date
when UL is sunsetting UL 563. Therefore, during the time between the
effective date of any final rule based on this proposal and September
29, 2024, manufacturers would be allowed to follow either UL 563, 8th
Edition or UL 60335-2-89, 2nd Edition. EPA is proposing allowing
manufacturers to adhere to either

[[Page 33740]]

standard for this limited time because the Agency recognizes that
manufacturers may need time to make necessary changes including to
their product labels. The period during which manufacturers may follow
either standard should provide sufficient time for manufacturers to
transition from UL 563 to UL 60335-2-89. EPA proposes that, beginning
September 30, 2024, R-290 may only be used in new self-contained
commercial ice machines that meet all requirements in UL 60335-2-89 for
the purposes of the SNAP program. See section II.H.1 for further
discussion on the requirements of this standard that EPA is proposing
to incorporate by reference.
In addition, we are proposing that manufacturers would need to
follow the set of use conditions that correspond with a specific UL
standard (i.e., when using UL 563, follow all existing use conditions
in listing 1 and when using UL 60335-2-89, follow all use conditions in
listing 3 in the proposed revisions to appendix V). After the
transition period ends, stand-alone units manufactured with R-290 would
need to follow UL 60335-2-89 for purposes of the SNAP program.
EPA also notes that we are not proposing to change two use
conditions that currently apply, nor are we taking comment on those
other use conditions. The use conditions that restrict the use of R-290
to new equipment specifically designed for this refrigerant, and that
require red-colored markings at service ports, pipes, hoses, and other
devices through which the refrigerant is serviced, are current use
conditions for R-290 in new self-contained commercial ice machines.
If the regulatory text is finalized as proposed, EPA would amend to
add use conditions that apply to R-290 in new self-contained commercial
ice machines manufactured on or after the effective date of the final
rule. Equipment manufactured before the effective date of the final
rule would not be affected by this action and would hence be subject to
the current use conditions included in appendix V.
6. How do the proposed use conditions for commercial ice machines
differ from the existing ones and why is EPA proposing to change the
use conditions?
The updated use conditions EPA is proposing are similar to the ones
that exist today in appendix V to 40 CFR part 82, subpart G, for R-290
in this end-use. The proposed requirements that R-290 must be used in
new equipment only and that new self-contained commercial ice machines
must include red markings at service ports, pipes, hoses, and other
devices through which the refrigerant is serviced, are repeated in this
proposed listing. The revised use conditions concern incorporating by
reference the most recent U.S. national standard for commercial ice
machines and labeling requirements consistent with that new standard.
Self-contained commercial ice machines using R-290 manufactured before
the effective date of a final rule based on this proposal would not be
affected by the revised use conditions.
Warning labels are required under EPA's current regulations, and
EPA is proposing to continue to require them, although with some
specific language changes. EPA is proposing warning labels that are
identical to those required as use conditions for the use of R-290 in
self-contained commercial ice machines. EPA finds that using a common
set of labels, similar to those from UL 60335-2-89, would aid in
compliance and could reduce burden for the industry, especially for a
manufacturer that uses more than one refrigerant. EPA is proposing that
the labels must be provided in letters no less than 6.4 millimeter (\1/
4\ inch) high and must be permanent, which is identical to the current
requirement for R-290 in self-contained commercial ice machines.
EPA is proposing to update the standard incorporated by reference
in the use conditions, and after a transition period, replacing the
requirement to follow Supplement SA of the 8th edition of UL 563 with
the proposed requirement to adhere to the 2nd edition of UL 60335-2-89.
UL 60335-2-89 was developed in an open and consensus-based approach,
with the assistance of experts in the refrigeration and AC industry as
well as experts involved in assessing the safety of products. The
revision cycle for the 2nd edition, including final recirculation,
concluded with its publication on October 27, 2021. The 2021 standard
UL 60335-2-89 replaces the previously published version of several
standards, including UL 563, which had already been revised into an 8th
edition by that time. EPA was aware of the continuing progress of UL
Standards to address flammable refrigerants more appropriately. In this
document, we are proposing such a change knowing that UL is replacing
the standard to which such equipment is certified from UL 563 to the
newer UL 60335-2-89 as of September 30, 2024.
To allow time for manufacturers of self-contained commercial ice
machines to transition between the current use condition using the 8th
edition of UL 563, and the new use condition using the 2nd edition of
UL 60335-2-89, EPA is proposing to allow R-290 to be used in self-
contained commercial ice machines manufactured either following UL 563
or UL 60335-2-89 during a transition period. We propose that transition
period would begin on the effective date of any final rule based on
this proposal and would last through September 29, 2024. It is EPA's
understanding that UL intends to sunset UL 563 on September 29, 2024,
and EPA is proposing to coordinate with that sunset date. Beginning
September 30, 2024, the use condition in effect would only allow R-290
to be used in new self-contained commercial ice machines that follow UL
60335-2-89. In addition, we are proposing that manufacturers would need
to follow the set of use conditions that correspond with a specific UL
standard (i.e., when using UL 563, follow all use conditions in listing
1 and when using UL 60335-2-89, follow all use conditions in listing 3
in the proposed revisions to appendix V).
Incorporating UL 60335-2-89 by reference in a use condition would
allow the industry to manufacture and test refrigeration equipment
following the most recent standard, which provides additional
flexibility and safeguards when using flammable refrigerants. The
transition period when equipment may follow either UL standard would be
helpful in implementing any transitions needed or planned for
manufacturers, installers, and technicians. A manufacturer, who may
offer different products within this end-use with different
refrigerants, could use similar processes, such as in developing and
applying the warning labels required.
Another proposed revision to the use conditions is the limit on
charge sizes. The current use conditions from SNAP Rule 21 require the
charge sizes from UL 563 calculated consistent with UL 563, with a
maximum charge size of 150 g allowed. The proposed revised use
conditions for equipment manufactured on or after the effective date of
any final rule would allow charge sizes calculated based on UL 60335-2-
89, which would allow charge sizes of R-290 up to approximately 500 g
for open equipment, 300 g for equipment with doors or drawers, or 115 g
for equipment near a pathway for egress. These changes would allow the
use of R-290 in larger equipment than previously and would provide more
options for industry, while maintaining safety.
Because of the differences between UL 563 and UL 60335-2-89, EPA
performed a new risk screen for R-290 as a refrigerant in commercial
ice

[[Page 33741]]

machines.\45\ In this risk screen, EPA adjusted charge sizes to be
consistent with the larger charge sizes allowed for R-290 under UL
60335-2-89. The risk screen also considered the impact of mitigation
methods such as valves that would restrict the amount of refrigerant
that could be released. The updated risk screen found that
concentrations of R-290 still would not exceed the LFL when used
according to the proposed use condition and consistent with UL 60335-2-
89, and thus the proposed new use conditions would also address
potential flammability risks of using R-290.\46\ In addition, the risk
screen modeled the reasonable worst-case scenario of short-term
exposure (15-minute TWA) due to a catastrophic release of the charge.
Under this highly conservative scenario, the worst-case exposure was
still significantly lower than the ATEL of 50,000 ppm.\47\ For further
information, see the risk screen in the docket for this rulemaking.
---------------------------------------------------------------------------

\45\ ICF, 2023q. Op. cit.
\46\ Ibid.
\47\ Ibid.
---------------------------------------------------------------------------

7. What additional information is EPA including in this proposed
listing?
EPA is providing additional information related to this proposed
listing. Since this additional information is not part of the
regulatory decision under SNAP, these statements are not binding for
use of the substitute under the SNAP program. See section II.H.2 for
further discussion on what additional information EPA is including in
these proposed listings. EPA notes that the additional information is
similar to, but not identical with, the addition information in the
listing for R-290 in self-contained commercial ice machines in SNAP
Rule 21. EPA is proposing additional information consistent with that
included in the other proposed listings for stand-alone units in this
rule and consistent with that included in the listings for R-290 as
acceptable, subject to use conditions, in self-contained commercial ice
machines in Rule 21. While the items listed are not legally binding
under the SNAP program, EPA encourages users of substitutes to apply
all statements in the ``Further Information'' column in their use of
these substitutes.
8. On which topics is EPA specifically requesting comment?
EPA is requesting comment on all aspects of the proposed updates to
the use conditions as discussed in this section II.D. EPA requests
comments on the proposed change in use conditions and if and how such
change would affect the safety of self-contained commercial ice
machines using R-290. EPA is requesting comment on the risk mitigation
offered by compliance with the current version of the standard proposed
as use conditions, i.e., UL 60335-2-89, the nature of updates proposed
for this standard, and the expected timeline for those updates. The
Agency also requests comment on allowing a transition period where
either of two sets of use conditions, including either UL 563 or UL
60335-2-89, may be followed and on the specific dates for the
transition period. EPA is requesting comment on the applicability of
the 2nd edition of UL 60335-2-89 to new self-contained commercial ice
machines, including which types of equipment, under which applications
the standard applies, and whether the listing of R-290 should apply to
commercial ice machines that have a remote compressor and are not self-
contained.

E. Industrial Process Refrigeration--Proposed Listing of HFC-32, HFO-
1234yf, HFO-1234ze(E), R-454A, R-454B, R-454C, R-455A, R-457A, and R-
516A as Acceptable, Subject to Use Conditions, for Use in New
Industrial Process Refrigeration

EPA is proposing to list HFC-32, HFO-1234yf, HFO-1234ze(E), and the
refrigerant blends R-454A, R-454B, R-454C, R-455A, R-457A, and R-516A
as acceptable, subject to use conditions, for use in new industrial
process refrigeration.
Most of the use conditions proposed for the proposed A2L
refrigerants when used in IPR are the same as those proposed for other
end-uses. Because of this similarity, EPA discusses the use conditions
that would apply to all five end-uses in section II.H. In summary, the
common use conditions proposed include the following: restricting the
use of each refrigerant to new equipment that is specifically designed
for that refrigerant; use consistent with the 2nd edition of UL 60335-
2-89, including testing, charge sizes, ventilation, usage space
requirements, and certain hazard warnings and markings; and
requirements for warning labels and markings on equipment to inform
consumers, technicians, and first responders of potential flammability
hazards.
The following use condition also applies for R-32 and R-454B in
industrial process refrigeration: these substitutes may only be used in
chillers for IPR.
The following use condition also applies for R-454A in IPR: this
substitute may only be used either in chillers for IPR, in equipment
with a refrigerant charge capacity less than 200 pounds, or in the high
temperature side of a cascade system.
The regulatory text of the proposed decisions appears in tables at
the end of this document. If finalized as proposed, this text would be
codified in appendix Y to 40 CFR part 82, subpart G. The proposed
regulatory text contains listing decisions for the end-use discussed
above. EPA notes that there may be other legal obligations pertaining
to the manufacture, use, handling, and disposal of the proposed
refrigerants that are not included in the information listed in the
tables (e.g., the CAA section 608(c)(2) venting prohibition, or DOT
requirements for transport of flammable gases). Flammable refrigerants
being recovered or otherwise disposed of from IPR equipment are likely
to be hazardous waste under RCRA (see 40 CFR parts 260 through 270).
1. Background on Industrial Process Refrigeration
IPR systems cool process streams in industrial applications, for
example, machining of metal products, fermentation of beer, or
operation of hydraulic circuits. The choice of substitute for specific
applications depends on ambient and required operating temperatures and
pressures. It is EPA's understanding that this type of equipment
generally falls under the scope of UL 60335-2-89, ``Requirements for
Commercial Refrigerating Appliances and Ice-Makers with an Incorporated
or Remote Refrigerant Unit or Motor-Compressor.'' In contrast,
industrial process air conditioning primarily cools people, may also
cool processes, and follows a different UL standard. In addition,
sometimes chillers are used primarily to cool process streams, rather
than for comfort cooling. EPA describes this application as ``chillers
in IPR.''
2. What are the ASHRAE classifications for refrigerant flammability?
ASHRAE 34-2022 categorizes the refrigerants proposed for IPR in
this section as being in the A2L Safety Group. See section II.A.2 for
further discussion on ASHRAE classifications.
3. What are HFC-32, HFO-1234yf, HFO-1234ze(E), R-454A, R-454B, R-454C,
R-455A, R-457A, and R-516A and how do they compare to other
refrigerants in the same end-use?
See section II.A.3 for further discussion on the environmental,
flammability, toxicity, and exposure information for these
refrigerants.

[[Page 33742]]

The redacted submission and supporting documentation for HFC-32,
HFO-1234yf, HFO-1234ze(E), blends R-454A, R-454B, R-454C, R-455A, R-
457A, and R-516A is provided in the docket for this proposed rule (EPA-
HQ-OAR-2023-0043) at <a href="https://www.regulations.gov">https://www.regulations.gov</a>. EPA performed risk
screening assessments to examine the health and environmental risks of
these substitutes. These risk screens are available in the docket for
this proposed rule.48 49 50 51 52 53 54 55 56
---------------------------------------------------------------------------

\48\ ICF, 2023r. Risk Screen on Substitutes in Industrial
Process Refrigeration (New Equipment); Substitute: HFC-32
(Difluoromethane).
\49\ ICF, 2023s. Risk Screen on Substitutes in Industrial
Process Refrigeration, Cold Storage Warehouses, and Ice Skating
Rinks (New Equipment); Substitute: HFO-1234yf.
\50\ ICF, 2023t. Risk Screen on Substitutes in Industrial
Process Refrigeration, Cold Storage Warehouses, and Ice Skating
Rinks (New Equipment); Substitute: HFO-1234ze(E) (Solstice[supreg]
ze, Solstice[supreg] 1234ze).
\51\ ICF, 2023u. Risk Screen on Substitutes in Industrial
Process Refrigeration and Cold Storage Warehouses (New Equipment);
Substitute: R-454A (Opteon[supreg] XL40).
\52\ ICF, 2023v. Risk Screen on Substitutes in Industrial
Process Refrigeration (New Equipment); Substitute: R-454B
(Opteon[supreg] XL41).
\53\ ICF, 2023w. Risk Screen on Substitutes in Industrial
Process Refrigeration, Cold Storage Warehouses, and Ice Skating
Rinks (New Equipment); Substitute: R-454C (OpteonTM
XL20).
\54\ ICF, 2023x. Risk Screen on Substitutes in Industrial
Process Refrigeration, Cold Storage Warehouses, and Ice Skating
Rinks (New Equipment); Substitute: R-455A (Solstice[supreg] L40X).
\55\ ICF, 2023y. Risk Screen on Substitutes in Industrial
Process Refrigeration, Cold Storage Warehouses, and Ice Skating
Rinks (New Equipment); Substitute: R-457A.
\56\ ICF, 2023z. Risk Screen on Substitutes in Industrial
Process Refrigeration, Cold Storage Warehouses, and Ice Skating
Rinks (New Equipment); Substitute: R-516A.
---------------------------------------------------------------------------

Comparison to other substitutes in this end-use: HFC-32, HFO-
1234yf, HFO-1234ze(E), and blends R-454A, R-454B, R-454C, R-455A, R-
457A, and R-516A all have an ODP of zero, comparable to or lower than
some of the acceptable substitutes in new IPR equipment, such as HFC-
134a, R-410A, and R-513A with ODPs of zero and hydrochlorofluoroolefin
(HCFO)-1233zd(E) with an ODP less than 0.0004.\57\
---------------------------------------------------------------------------

\57\ WMO, 2018.
---------------------------------------------------------------------------

HFO-1234yf and HFO-1234ze(E) have GWPs less than four and less than
six, respectively, comparable to that of R-290 and ammonia with GWPs of
3 and zero. R-454A, R-454B, R-454C, R-455A, R-457A, and R-516A have
GWPs ranging from 140 to 470, higher than some of the acceptable
substitutes for new IPR equipment, including R-290 and ammonia, and
lower than those of other substitutes such as R-450A and R-513A with
GWPs of about 600 and 630. HFC-32 has a GWP of 675, which is higher
than some of the acceptable substitutes including R-290, R-450A, and R-
513A; however, the GWP of HFC-32 is lower than those of R-410A and R-
404A, with GWPs of approximately 2,090 to 3,920, which are refrigerant
that have typically been employed in chillers for IPR.
Information regarding the toxicity of other available alternatives
is provided in the previous listing decisions for new IPR (<a href="https://www.epa.gov/snap/substitutes-industrial-process-refrigeration">https://www.epa.gov/snap/substitutes-industrial-process-refrigeration</a>).
Toxicity risks of use, determined by the likelihood of exceeding the
exposure limits of HFC-32, HFO-1234yf, HFO-1234ze(E), R-454A, R-454B,
R-454C, R-455A, R-457A, and R-516A in this end-use, is evaluated in the
risk screens referenced above. The toxicity risks of using HFO-1234yf
and the refrigerant blends in IPR, and of using all nine refrigerants
in chillers for IPR, are comparable to or lower than toxicity risks of
other available substitutes in the same end-use. Toxicity risks of the
proposed refrigerants can be mitigated by use consistent with ASHRAE
15-2022 and other industry standards, recommendations in the
manufacturers' SDS, and other safety precautions common in the
refrigeration and AC industry.
The flammability risks with HFC-32, HFO-1234yf, HFO-1234ze(E), R-
454A, R-454B, R-454C, R-455A, R-457A, and R-516A in the IPR end-use,
determined by the likelihood of exceeding their respective lower
flammability limits, are evaluated in the risk screens referenced in
this section above. While these refrigerants may pose greater
flammability risk than available substitutes in the new IPR end-use
that are non-flammable, this risk can be mitigated by use consistent
with ASHRAE 15-2022 and UL 60335-2-89, required by our proposed use
conditions, as well as recommendations in the manufacturers' SDS and
other safety precautions common in the refrigeration and AC industry.
We also note that other acceptable refrigerants in the IPR end-use have
higher flammability and are classified in the A3 Safety Group, such as
R-290, butane (R-600), and propylene (R-1270). EPA is proposing use
conditions to reduce the potential risk associated with the
flammability of the proposed alternatives so that they will not pose
significantly greater risk than other acceptable substitutes in the new
IPR end-use.
In addition, the proposed substitutes have lower GWPs than most
other available alternatives for the same uses. The proposed
refrigerants may provide additional lower-GWP options for situations
where other refrigerants with lower GWPs are not viable, such as
situations where sparks or flame might occur such that HCs are not
suitable for use, or for systems with remote compressors or equipment
requiring larger charge sizes, where refrigerant leaks are more likely
to create greater flammability risk. Given the wide range of
applications for IPR, not all refrigerants listed as acceptable under
SNAP will be suitable for the range of equipment in the IPR end-use. To
provide additional options to ensure the availability of substitutes
for the full range of IPR equipment with lower GWP and, therefore,
lower overall risk to human health and the environment, EPA is
proposing the listings for HFO-1234yf, HFO-1234ze(E), R-454C, R-455A,
R-457A, and R-516A as acceptable, subject to use conditions, for use in
IPR.
EPA is also proposing to list the refrigerants HFC-32 and R-454B
with a use condition restricting their use to chillers in IPR. These
refrigerants have higher GWPs than the other refrigerants EPA is
proposing to list as acceptable, subject to use conditions; lower GWPs
than many currently listed acceptable substitutes for IPR that are
commonly in use; and lower flammability than HC refrigerants currently
listed as acceptable in IPR. The Agency expects that these refrigerants
may provide additional, lower-GWP options for chillers for IPR, where
greater volumetric capacity and higher operating pressures may be
required to operate properly than for other types of IPR equipment
(e.g., direct expansion systems), to address applications where other
substitutes with lower GWPs may not be technically feasible.
EPA is also proposing to list the refrigerant R-454A with a use
condition that this substitute may only be used either in chillers for
IPR, in equipment with a refrigerant charge capacity less than 200
pounds, or in the high temperature side of a cascade system. This
refrigerant may provide additional, lower-GWP options for chillers for
IPR, where greater volumetric capacity and higher operating pressures
may be required to operate properly than for other types of IPR
equipment. R-454A may also address the additional challenges for
finding lower GWP refrigerants with higher capacity for ice skating
rinks with moderate charge sizes and for cascade systems, EPA is
proposing to list R-454A as acceptable, subject to use conditions, for
use in new ice skating rinks with a charge size capacity less than 200
pounds or for use

[[Page 33743]]

in the high-temperature side of a cascade system.
4. Why is EPA proposing these specific use conditions?
The use conditions identified in the proposed listings above for
all nine refrigerants are explained in section II.H.1 in greater
detail.
EPA is proposing the use condition for HFC-32 and R-454B
restricting their use to chillers for IPR because these substitutes
have higher GWPs than many of the available substitutes in IPR (e.g.,
HCs, HFOs); however, because chillers may require greater volumetric
capacity than other types of IPR equipment (e.g., DX systems), EPA is
proposing to list these two additional refrigerants to provide
additional options and to address a broader range of equipment and
applications. EPA also is proposing a use condition for R-454A that
would allow its use in chillers for IPR, as well as other certain other
applications, as described below in this section. In addition, the
Agency previously listed HFC-32, R-454A, and R-454B as acceptable,
subject to use conditions, in centrifugal and positive displacement
chillers for comfort cooling in SNAP Rule 25. EPA is proposing to list
the same refrigerants the same way for the same type of equipment
(chillers) because of similar technical issues, such as volumetric
capacity and operating pressure, which restrict the technical viability
of alternatives for some applications.
EPA is proposing to list R-454A as acceptable, subject to use
conditions, in IPR with a use condition that this substitute may only
be used in chillers for IPR, in equipment with a refrigerant charge
capacity less than 200 pounds or in the high-temperature side of a
cascade system. EPA is proposing to allow use of R-454A for use in
chillers for IPR for the same reasons as above for HFC-32 and R-454B.
The Agency is also proposing this use condition to allow use of R-454A
less broadly than for the refrigerants HFO-1234yf, HFO-1234ze(E), R-
454C, R-455A, R-457A, and R-516A because its GWP is higher than those
other proposed listings for non-chiller IPR equipment (that has a GWP
of about 240, compared to less than four to 150). EPA's understanding
is that, in addition to the technical constraints for refrigerant in
chillers, there are two more situations where use of refrigerants is
likely to be more constrained, and thus, additional refrigerant options
may be helpful. The first of those situations is in what industry
standard ASHRAE 15-2022 identifies as a refrigerating system having a
``high probability'' that leaked refrigerant from a failed connection,
seal, or component could enter an occupied area. An example of such a
constraint is that ASHRAE 15-2022 and UL 60335-2-89 effectively set
charge limits for A2L refrigerants to less than 200 pounds for
applications inside an occupied space where people might be located. In
contrast, larger charge sizes could be used in ``low-probability''
locations where the general public is unlikely to come in contact with
the refrigerant, such as systems used outdoors or in a machinery room
with access restricted to facility employees. Where the general public
is unlikely to come into contact with any leaked refrigerant, such as
where charge sizes of 200 pounds or more of A2L refrigerant would be
allowed under the use conditions incorporating UL 60335-2-89 and ASHRAE
15-2022, there would be fewer space constraints and greater flexibility
in equipment design, so refrigeration system designers can accommodate
a narrower set of substitutes. Conversely, where people are more likely
to come into contact with any leaked refrigerant in an interior space,
refrigerant charge capacities of a system would be less than 200
pounds; there would be more space constraints, less flexibility in
equipment design, and potentially stricter code requirements, leading
to a need for more refrigerant options. Allowing the additional option
of R-424A for non-chiller IPR equipment with smaller refrigerant
charges would enable the use of a wider set of available substitutes to
manage safety (in particular, flammability and toxicity), as well as
allowing more options to achieve adequate performance where there may
be more constraints. Therefore, EPA is proposing to list R-454A as
acceptable, subject to use conditions, only for non-chiller IPR
equipment with a refrigerant charge capacity less than 200 pounds.
EPA is also proposing to list R-454A as acceptable, subject to use
conditions, for use in the high temperature side of cascade systems
used for non-chiller IPR equipment. As discussed above in section
II.A.1, ``Background on retail food refrigeration,'' each system of a
cascade system uses a different refrigerant that is most suitable for
the given temperature range. Higher temperature systems, or the ``high
temperature side,'' have typically used HFCs as a refrigerant; however,
it is technologically achievable and has become more common to use
ammonia in the high temperature side. For lower temperature systems, or
the ``low temperature side'' of the cascade system, low boiling
refrigerants such as R-744 can be used. Considerations for the choice
of refrigerant on the high or low temperature side of cascade systems
are influenced by many factors including, but not limited to, a
refrigerant's toxicity and flammability, its temperature glide, and its
suitability to lower temperature applications. EPA understands that use
of flammable or toxic refrigerants, such as ammonia, on the high
temperature side of a cascade may be limited in certain circumstances
(e.g., based on building codes and/or standards). EPA notes that there
are a number of substitutes available for the low temperature side of
the cascade system with GWPs lower than that of R-454A. Therefore,
instead of proposing to list R-454A as acceptable, subject to narrowed
use limits and subject to use conditions, EPA is proposing to list R-
454A as acceptable, subject to use conditions, when it is used in the
high temperature side of cascade systems; this would expand the
refrigerant options that can comply with local building codes and
industry safety standards while meeting the more challenging
application of the high temperature side of a cascade system.
5. What additional information is EPA including in these proposed
listings?
EPA is providing additional information related to these proposed
listings. Since this additional information is not part of the
regulatory decision under SNAP, these statements are not binding for
use of the substitute under the SNAP program. See section II.H.2 for
further discussion on what additional information EPA is including in
these proposed listings. While the items listed are not legally binding
under the SNAP program, EPA encourages users of substitutes to apply
all statements in the ``Further Information'' column in their use of
these substitutes.
6. On which topics is EPA specifically requesting comment?
EPA is requesting comment on all aspects of the proposed decision
to list HFC-32, HFO-1234yf, HFO-1234ze(E), and the refrigerant blends
R-454A, R-454B, R-454C, R-455A, R-457A, and R-516A acceptable, subject
to use conditions, in IPR as discussed in this section II.E. EPA seeks
comment on the risk mitigation offered by the proposed use conditions,
including requiring compliance with the 2nd edition of UL 60335-2-89,
except to the extent the proposed rule conflicts with the UL standard,
in which case we propose that the conditions specified in the rule
would apply. We also request comment

[[Page 33744]]

on whether other use conditions would offer needed risk mitigation for
the flammable refrigerants proposed. EPA requests comment on whether
types of IPR equipment have been designed for the refrigerants
proposed; any information on the safety of such equipment in other
countries; and if and how such experience would translate to safe use
in the United States. The Agency requests comment on whether HFC-32, R-
454A, and R-454B should be listed as acceptable for chillers in IPR
given their higher GWP than some other alternatives listed as
acceptable, if they should not be listed in IPR at all, or if they
should be listed as acceptable for all types of IPR equipment, and if
so, why. Depending on public comments and information received, EPA may
revise the substitutes listed with a use condition for use only in
chillers for IPR or may not finalize some of the proposed listings.

F. Cold Storage Warehouses--Proposed Listing of HFO-1234yf, HFO-
1234ze(E), R-454A, R-454C, R-455A, R-457A and R-516A as Acceptable,
Subject to Use Conditions, for Use in New Cold Storage Warehouses

EPA is proposing to list HFO-1234yf, HFO-1234ze(E), and the
refrigerant blends R-454A, R-454C, R-455A, R-457A, and R-516A as
acceptable, subject to use conditions, for use in new cold storage
warehouses.
Several use conditions proposed for cold storage warehouses are
common to those proposed for the other end-uses in this rule. Because
of this similarity, EPA discusses the use conditions that would apply
to all five end-uses in section II.H. In summary, the common use
conditions proposed include the following: restricting the use of each
refrigerant to new equipment that is specifically designed for that
refrigerant; use consistent with the 2nd edition of UL 60335-2-89,
including testing, charge sizes, ventilation, usage space requirements,
and certain hazard warnings and markings; and requirements for warning
labels and markings on equipment to inform consumers, technicians, and
first responders of potential flammability hazards.
The following proposed use condition would also apply to R-454A in
cold storage warehouses: this substitute may only be used either in
equipment with a refrigerant charge capacity less than 200 pounds or in
the high temperature side of a cascade system.
The regulatory text of the proposed decisions appears in tables at
the end of this document. If finalized as proposed, this text would be
codified in appendix Y to 40 CFR part 82, subpart G. The proposed
regulatory text contains listing decisions for the end-use discussed
above. EPA notes that there may be other legal obligations pertaining
to the manufacture, use, handling, and disposal of the proposed
refrigerants that are not included in the information listed in the
tables (e.g., the CAA section 608(c)(2) venting prohibition, or
Department of Transportation requirements for transport of flammable
gases). Flammable refrigerants being recovered or otherwise disposed of
from cold storage warehouses are likely to be hazardous waste under
RCRA (see 40 CFR parts 260 through 270).
1. Background on Cold Storage Warehouses
Cold storage warehouses, an end-use within the SNAP program, are
refrigerated warehousing and are used to preserve meat, produce, dairy
products, and other perishable goods prior to their distribution and
sale.
Refrigerant choices depend on the refrigerant charge, ambient
temperatures and the temperature required, system performance, energy
efficiency, and health, safety and environmental considerations, among
other things. The majority of cold storage warehouses in the United
States use ammonia as the refrigerant in a vapor compression cycle,
although some rely on other refrigerants. In addition to regulations
pursuant to the SNAP program, other federal or local regulations may
also affect refrigerant choice. For instance, regulations from OSHA may
restrict or place requirements on the use of some refrigerants, such as
ammonia (R-717). Building codes from local and state agencies may also
incorporate limits on the charge size of particular refrigerants. EPA
understands that this type of equipment falls under the scope of UL
60335-2-89, ``Household and Similar Electrical Appliances--Safety--Part
2-89: Requirements for Commercial Refrigerating Appliances and Ice-
Makers with an Incorporated or Remote Refrigerant Unit or Motor-
Compressor.''
EPA is proposing to list HFO-1234yf, HFO-1234ze(E), R-454A, R-454C,
R-455A, R-457A, and R-516A as acceptable, subject to use conditions, in
new cold storage warehouses.
2. What are the ASHRAE classifications for refrigerant flammability?
ASHRAE 34-2022 categorizes the refrigerants proposed for cold
storage warehouses in this section as being in the A2L Safety Group.
See section II.A.2 for further discussion on ASHRAE classifications of
these refrigerants.
3. What are HFO-1234yf, HFO-1234ze(E), R-454A, R-454C, R-455A, R-457A,
and R-516A and how do they compare to other refrigerants in the same
end-use?
See section II.A.3 for further discussion on the environmental,
flammability, toxicity, and exposure information for HFO-1234yf, HFO-
1234ze(E), R-454A, R-454C, R-455A, R-457A, and R-516A.\58\
---------------------------------------------------------------------------

\58\ EPA previously listed HFO-1234yf as acceptable, subject to
use conditions, in motor vehicle AC in light-duty vehicles (74 FR
53445, October 19, 2009), in heavy-duty pickup trucks and complete
heavy-duty vans (81 FR 86778, December 1, 2016) and in nonroad
vehicles and service fittings for small refrigerant cans (87 FR
26276, May 4, 2022). EPA previously listed R-454A, R-454C, and R-
457A as acceptable subject to use conditions as substitutes in
residential and light commercial AC and HPs (86 FR 24444, May 6,
2021).
---------------------------------------------------------------------------

Redacted submissions and supporting documentation for HFO-1234yf,
HFO-1234ze(E), and the refrigerant blends are provided in the docket
for this proposed rule (EPA-HQ-OAR-2023-0043) at <a href="https://www.regulations.gov">https://www.regulations.gov</a>. EPA performed risk screening assessments to
examine the health and environmental risks of each of these
substitutes. These risk screens are available in the docket for this
proposed rule.59 60 61 62 63 64 65
---------------------------------------------------------------------------

\59\ ICF, 2023s. Op. cit.
\60\ ICF, 2023t. Op. cit.
\61\ ICF, 2023u. Op. cit.
\62\ ICF, 2023w. Op. cit.
\63\ ICF, 2023x. Op. cit.
\64\ ICF, 2023y. Op. cit.
\65\ ICF, 2023z. Op. cit.
---------------------------------------------------------------------------

Comparison to other substitutes in this end-use: HFO-1234yf, HFO-
1234ze(E), and R-454A, R-454C, R-455A, R-457A, and R-516A all have an
ODP of zero, comparable to or lower than some of the acceptable
substitutes in this end-use, such as ammonia with an ODP of zero and
HCFO-1233zd(E) with an ODP less than 0.0004.
HFO-1234yf and HFO-1234ze(E) have GWPs less than four and less than
six, respectively, comparable to that of (HCFO)-1233zd(E),
CO<INF>2</INF>, and ammonia with GWPs of 3.7, one, and zero
respectively. R-454A, R-454C, R-455A, R-457A, and R-516A have GWPs
ranging from 140 to 270, higher than some of the acceptable substitutes
for new cold storage warehouses, including HCFO-1233zd(E),
CO<INF>2</INF>, and ammonia with GWPs of 3.7, one, and zero,
respectively, and lower than those of other acceptable substitutes such
as R-450A, R-513A, and R-407F with GWPs of about 600, 630, and 1,820,
respectively.
Information regarding the toxicity of other available alternatives
is provided in the listing decisions previously made (see https://
www.epa.gov/snap/

[[Page 33745]]

substitutes-cold-storage-warehouses). Toxicity risks of use, determined
by the likelihood of exceeding the exposure limit of HFO-1234yf, HFO-
1234ze(E), and the refrigerant blends in these end-uses, are evaluated
in the risk screens referenced above. The toxicity risks of using HFO-
1234yf, HFO-1234ze(E), and the refrigerant blends in commercial
refrigeration are comparable to or lower than toxicity risks of other
available substitutes in the same end-use. Toxicity risks of the
proposed refrigerants can be minimized by use consistent with ASHRAE
15-2022 and other industry standards, recommendations in the
manufacturers' SDS, and other safety precautions common in the
refrigeration and AC industry.
The flammability risks with HFO-1234yf, HFO-1234ze(E), R-454A, R-
454C, R-455A, R-457A, and R-516A in this end-use, determined by the
likelihood of exceeding their respective lower flammability limits, are
evaluated in the risk screens referenced above. In conclusion, while
these refrigerants may pose greater flammability risk than other
available, non-flammable substitutes in the same end-use, this risk can
be minimized by use consistent with ASHRAE 15-2022 and other industry
standards such as UL 60335-2-89--which is required by our proposed use
conditions--as well as recommendations in the manufacturers' SDS and
other safety precautions common in the refrigeration and AC industry.
EPA is proposing use conditions to reduce the potential risk associated
with the flammability of these alternatives so that they will not pose
significantly greater risk than other acceptable substitutes in this
end-use.
The proposed refrigerants provide additional lower-GWP options for
situations where other refrigerants with lower GWPs are not viable,
such as for use of ammonia in systems with remote compressors or in
locations where local regulations restrict its use, or where a lower
pressure refrigerant like HCFO-1233zd(E) is not technically viable. Not
all refrigerants listed as acceptable under SNAP will be suitable for
the range of equipment in the cold storage warehouse end-use. To
provide additional options to ensure the availability of substitutes
for the full range of cold storage warehouses with lower GWP and,
therefore, lower overall risk to human health and the environment, EPA
is proposing the listings for HFO-1234yf, HFO-1234ze(E), R-454C, R-
455A, R-457A, and R-516A as acceptable, subject to use conditions, for
use in all types of cold storage warehouses. In addition, to account
for the additional challenges for finding lower GWP refrigerants for
cold storage warehouses with moderate charge sizes and for cascade
systems, EPA is proposing to list R-454A as acceptable, subject to use
conditions, for use in cold storage warehouses with a charge size
capacity less than 200 pounds or for use in the high-temperature side
of a cascade system.
4. Why is EPA proposing these specific use conditions?
The proposed use conditions identified in the proposed listings
above are explained in section II.H.1.
This proposal applies to end-uses covered by UL 60335-2-89,
including the SNAP cold storage warehouses end-use. In addition, ASHRAE
15-2022 applies to these refrigeration systems.
The standard UL 60335-2-89 discussed in section II.H indicates that
refrigerant charges greater than a specific amount (called
``m<INF>3</INF>'' in the standard and based on the refrigerant's LFL)
are beyond its scope and that national standards might apply, such as
ASHRAE 15-2022. Hence, EPA is proposing to require adherence to both
standards as use conditions for cold storage warehouses, broadening the
coverage under this proposed rule.
EPA is proposing to incorporate by reference ASHRAE 15-2022,
including all addenda published by the date of this proposal, in use
conditions that apply to use of the proposed A2L refrigerants in new
cold storage warehouses. Where the requirements specified in this
proposed rule (if finalized) and ASHRAE 15-2022 differ, the
requirements of this rule would apply.
EPA recognizes that ASHRAE 15-2022 is undergoing continuous
maintenance with publication of periodic addenda and is typically
updated and republished every three years. While this proposed rule
incorporates all addenda to ASHRAE 15-2022 published by the date of
this proposal, there may be additional changes by the time EPA issues a
final rule based upon this proposal. However, given EPA would not have
reviewed and proposed use conditions based on those changes, EPA is not
proposing to include addenda or other changes made to ASHRAE 15-2022
after the date of the proposed rule.
EPA is proposing to list R-454A as acceptable, subject to use
conditions, in cold storage warehouses with a use condition that this
substitute may only be used either in equipment with a refrigerant
charge capacity less than 200 pounds or in the high-temperature side of
a cascade system. The Agency is proposing this use condition to allow
use of R-454A less broadly than for the other refrigerants proposed for
use in cold storage warehouses because its GWP is higher than those of
the other proposed listings for this end-use (about 240, compared to
less than four to 150). EPA's understanding is that there are two
particular situations where use of refrigerants could be more
constrained, and thus, additional refrigerant options may be helpful.
The first of those situations is in what the industry standard ASHRAE
15-2022 identifies as a refrigerating system having a ``high
probability'' that leaked refrigerant from a failed connection, seal,
or component could enter an occupied area. An example of such a
constraint is that ASHRAE 15-2022 and UL 60335-2-89 effectively set
charge limits for A2L refrigerants to less than 200 pounds for
applications inside occupied areas. In contrast, larger charge sizes
could be used in ``low-probability'' locations where people are
unlikely to come in contact with the refrigerant, such as systems used
outdoors or in a machinery room with access restricted to employees.
Where people are unlikely to come into contact with any leaked
refrigerant, such as where charge sizes of 200 pounds or more of A2L
refrigerant would be allowed under the use conditions incorporating UL
60335-2-89 and ASHRAE 15-2022, there would be fewer space constraints
and greater flexibility in equipment design, so refrigeration system
designers can accommodate a narrower set of substitutes. Conversely,
where people are more likely to come into contact with any leaked
refrigerant in an interior space, refrigerant charge capacities of a
system would be less than 200 pounds; there would be more space
constraints, less flexibility in equipment design, and potentially
stricter code requirements, leading to a need for more refrigerant
options. Allowing the additional option of R-454A for cold storage
warehouses with smaller refrigerant charges would enable the use of a
wider set of available substitutes to manage safety (in particular,
flammability and toxicity), as well as allowing more options to achieve
adequate performance where there may be more constraints. Therefore,
EPA is proposing to list R-454A as acceptable, subject to use
conditions, only for cold storage warehouses with a refrigerant charge
capacity less than 200 pounds.
EPA is also proposing to list R-454A as acceptable, subject to use
conditions, for use in the high temperature side of cascade systems
used for cold storage

[[Page 33746]]

warehouses. As discussed above in section II.A.1, ``Background on
retail food refrigeration,'' each system of a cascade system uses a
different refrigerant that is most suitable for the given temperature
range. Higher temperature systems, or the ``high temperature side,''
have typically used HFCs as a refrigerant; however, it is
technologically achievable and has become more common to use ammonia in
the high temperature side. For lower temperature systems, or the ``low
temperature side'' of the cascade system, low boiling refrigerants such
as R-744 can be used. Considerations for the choice of refrigerant on
the high or low temperature side of cascade systems are influenced by
many factors including, but not limited to, a refrigerant's toxicity
and flammability, its temperature glide, and its suitability to lower
temperature applications. EPA understands that use of flammable or
toxic refrigerants, such as ammonia, on the high temperature side of a
cascade may be limited in certain circumstances (e.g., based on
building codes and/or standards). EPA notes that there are a number of
substitutes available for the low temperature side of the cascade
system with GWPs lower than that of R-454A. Therefore, instead of
proposing to list R-454A as acceptable, subject to narrowed use limits
and subject to use conditions, EPA is proposing to list R-454A as
acceptable, subject to use conditions, when it is used in the high
temperature side of cascade systems; this would expand the refrigerant
options that can comply with local building codes and industry safety
standards while meeting the more challenging application of the high
temperature side of a cascade system.
5. What additional information is EPA including in these proposed
listings?
EPA is providing additional information related to these proposed
listings. Since this additional information is not part of the
regulatory decision under SNAP, these statements are not binding for
use of the substitute under the SNAP program. See section II.H.2 for
further discussion on what additional information EPA is including in
these proposed listings. While the items listed are not legally binding
under the SNAP program, EPA encourages users of substitutes to apply
all statements in the ``Further Information'' column in their use of
these substitutes.
6. On which topics is EPA specifically requesting comment?
EPA is requesting comment on all aspects of the proposed decision
to list HFO-1234yf, HFO-1234ze(E), R-454A, R-454C, R-455A, R-457A, and
R-516A acceptable, subject to use conditions, in new cold storage
warehouses as discussed in this section II.F. EPA seeks comment on the
risk mitigation offered by the proposed use conditions, including
requiring compliance with the 2nd edition of UL 60335-2-89 under the
SNAP program, except to the extent the proposed rule conflicts with the
UL Standard, in which case we propose that the use conditions specified
in the rule would apply. The Agency takes comment on our proposal to
limit R-454A to use either in equipment with a refrigerant charge
capacity less than 200 pounds or in the high temperature side of a
cascade system. We also request comment on whether EPA should consider
other use conditions to further mitigate potential risk from
refrigerants. EPA requests comment on whether cold storage warehouses
have been designed for or manufactured with the refrigerants proposed
and any information on the safety of such equipment in other countries,
and if and how such experience would translate to safe use in the
United States.

G. Ice Skating Rinks--Proposed Listing of HFO-1234yf, HFO-1234ze(E), R-
454C, R-455A, R-457A, and R-516A as Acceptable, Subject to Use
Conditions, for Use in New Ice Skating Rinks With a Remote Compressor

EPA is proposing to list HFO-1234yf, HFO-1234ze(E), and the
refrigerant blends R-454C, R-455A, R-457A, and R-516A as acceptable,
subject to use conditions, for use in new ice skating rinks.
Several use conditions proposed for ice skating rinks with a remote
compressor are common to those proposed for other end-uses. Because of
this similarity, EPA discusses the use conditions that would apply to
all five end-uses in section II.H. For ice skating rinks with remote
compressors, those are the only use conditions EPA is proposing. In
summary, the common use conditions proposed include the following:
restricting the use of each refrigerant to new equipment that is
specifically designed for that refrigerant; use consistent with the 2nd
edition of UL 60335-2-89, including testing, charge sizes, ventilation,
usage space requirements, and certain hazard warnings and markings; and
requirements for warning labels and markings on equipment to inform
consumers, technicians, and first responders of potential flammability
hazards.
The regulatory text of the proposed decisions appears in tables at
the end of this document. If finalized as proposed, this text would be
codified in appendix Y to 40 CFR part 82, subpart G. EPA notes that
there may be other legal obligations pertaining to the manufacture,
use, handling, and disposal of the proposed refrigerants that are not
included in the information listed in the tables (e.g., the CAA section
608(c)(2) venting prohibition, or DOT requirements for transport of
flammable gases). Flammable refrigerants being recovered or otherwise
disposed of from ice skating rinks are likely to be hazardous waste
under RCRA (see 40 CFR parts 260 through 270).
1. Background on Ice Skating Rinks
Ice skating rinks, an end-use within the SNAP program, are used by
the general public for recreational purposes and also include
professional rinks. These systems frequently use secondary loop
refrigeration systems, where a primary loop containing a refrigerant
uses a remote compressor that is in a location away from the public,
such as a machinery room, and a secondary loop, containing propylene
glycol, water, or another innocuous fluid, is used to directly cool the
ice. Other types of refrigeration systems for ice skating rinks use a
direct heat exchange system, where the refrigerant moves directly under
the rink. The proposed listings would apply only to ice skating rinks
that have a remote compressor.
Refrigerant choice depends on the refrigerant charge; ambient
temperatures and the temperature required; system performance; energy
efficiency; and health, safety, and environmental considerations, among
other things. In addition to regulations pursuant to the SNAP program,
other federal or local regulations may also affect refrigerant choice.
For instance, regulations from OSHA may restrict or place requirements
on the use of some refrigerants, such as ammonia (R-717). Building
codes from local and state agencies may also incorporate limits on the
amount of particular refrigerants used. Acceptable substitutes in use
today for new ice skating rinks include ammonia, CO<INF>2</INF>, HCFO-
1233zd(E) as well as HFCs and HFC/HFO blends. These can be used alone
or in combination with other refrigerants in other parts of the
equipment, depending on the equipment and its design (e.g., a secondary
loop contains one refrigerant while the primary loop contains a
different refrigerant). This type of equipment falls under the scope of
UL 60335-2-89, ``Requirements for Commercial Refrigerating Appliances
and Ice-Makers with an Incorporated or

[[Page 33747]]

Remote Refrigerant Unit or Motor-Compressor.''
2. What are the ASHRAE classifications for refrigerant flammability?
ASHRAE Standard 34-2022 categorizes the refrigerants proposed for
ice skating rinks in this section as being in the A2L Safety Group. See
section II.A.2 for further discussion on ASHRAE classifications of
these refrigerants.
3. What are HFO-1234yf, HFO-1234ze(E), R-454C, R-455A, R-457A, and R-
516A and how do they compare to other refrigerants in the same end-use?
See section II.A.3 for further discussion on the environmental,
flammability, toxicity, and exposure information for these
refrigerants.\66\
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\66\ EPA previously listed HFO-1234yf as acceptable, subject to
use conditions, in motor vehicle AC in light-duty vehicles (74 FR
53445, October 19, 2009), in heavy-duty pickup trucks and complete
heavy-duty vans (81 FR 86778, December 1, 2016) and in nonroad
vehicles and service fittings for small refrigerant cans (87 FR
26276, May 4, 2022). EPA previously listed R-454C, and R-457A as
acceptable, subject to use conditions, as substitutes in residential
and light commercial AC and HPs (86 FR 24444, May 6, 2021).
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Redacted submissions and supporting documentation for HFO-1234yf,
HFO-1234ze(E) and the blends R-454C, R-455A, R-457A and R-516A are
provided in the docket for this proposed rule (EPA-HQ-OAR-2023-0043) at
<a href="https://www.regulations.gov">https://www.regulations.gov</a>. EPA performed a risk screening assessment
to examine the health and environmental risks of each of these
substitutes. These risk screens are available in the docket for this
proposed rule.67 68 69 70 71 72
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\67\ ICF, 2023s. Op. cit.
\68\ ICF, 2023t. Op. cit.
\69\ ICF, 2023w. Op. cit.
\70\ ICF, 2023x. Op. cit.
\71\ ICF, 2023y. Op. cit.
\72\ ICF, 2023z. Op. cit.
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Comparison to other substitutes in this end-use: HFO-1234yf, HFO-
1234ze(E) and R-454C, R-455A, R-457A, and R-516A all have an ODP of
zero, comparable to or lower than some of the acceptable substitutes in
this end-use, such as ammonia with an ODP of zero and HCFO-1233zd(E)
with an ODP of less than 0.0004.
HFO-1234yf and HFO-1234ze(E) have GWPs of less than four and less
than six, respectively, comparable to or lower than that of other
acceptable substitutes for new ice skating rinks, such as ammonia,
CO<INF>2</INF>, and HCFO-1233zd(E) with GWPs of zero, one, and 3.7,
respectively.
R-454C, R-455A, R-457A, and R-516A have GWPs, ranging from about
140 to 150, which are higher than that of other acceptable substitutes
for ice skating rinks, including ammonia, CO<INF>2</INF>, and HCFO-
1233zd(E) with GWPs of zero, one, and 3.7, respectively. The GWPs of
HFO-1234yf, HFO-1234ze(E), R-454C, R-455A, R-457A, and R-516A are lower
than some of the acceptable substitutes for new ice skating rinks, such
as R-450A, R-449A, and R-507A with GWPs of approximately 600, 1,400,
and 3,990, respectively.
Information regarding the toxicity of other available alternatives
is provided in the listing decisions previously made (see <a href="https://www.epa.gov/snap/substitutes-ice-skating-rinks">https://www.epa.gov/snap/substitutes-ice-skating-rinks</a>). Toxicity risks of use,
determined by the likelihood of exceeding the exposure limit of HFO-
1234yf, HFO-1234ze(E), R-454C, R-455A, R-457A, and R-516A in these end-
uses, are evaluated in the risk screens referenced above. The toxicity
risks of using HFO-1234yf, HFO-1234ze(E), and R-454C, R-455A, R-457A
and R-516A in ice skating rinks with remote compressors are comparable
to or lower than toxicity risks of other available substitutes in the
same end-use. Toxicity risks of the proposed refrigerants can be
minimized by use consistent with ASHRAE 15-2022--which would be
required by our proposed use conditions--and other industry standards,
recommendations in the manufacturers' SDS, and other safety precautions
common in the refrigeration and AC industry.
The potential flammability risks of HFO-1234yf, HFO-1234ze(E) R-
454C, R-455A, R-457A, and R-516A in this end-use, determined by the
likelihood of exceeding their respective lower flammability limits, are
evaluated in the risk screens referenced above. In conclusion, while
these refrigerants may pose greater flammability risk than other
available substitutes in the same end-use, this risk can be minimized
by use consistent with ASHRAE 15-2022 and other industry standards such
as UL 60335-2-89--which is required by our proposed use conditions--as
well as recommendations in the manufacturers' SDS and other safety
precautions common in the refrigeration and AC industry. EPA is
proposing use conditions to reduce the potential risk associated with
the flammability of these alternatives so that they will not pose
significantly greater risk than other acceptable substitutes in this
end-use. In addition, EPA is proposing to limit these listings to
equipment with a remote compressor. Such equipment reduces the chances
of exposure to the general public compared to refrigerants that are
piped directly under an ice skating rink. This also can reduce the
amount of refrigerant used, potentially reducing climate impacts of any
refrigerant released.
In addition, the proposed substitutes have lower GWPs than most
other available alternatives for the same end-use. The proposed
refrigerants may provide additional lower-GWP options for situations
where other refrigerants with lower GWPs are not viable, such as in
locations where local regulations restrict use of ammonia. Not all
refrigerants listed as acceptable under SNAP will be suitable for the
range of equipment in the ice skating rinks end-use. To provide
additional options to ensure the availability of substitutes with lower
GWP for more ice skating rinks and, therefore, lower overall risk to
human health and the environment, EPA is proposing the listings for
HFO-1234yf, HFO-1234ze(E), R-454C, R-455A, R-457A, and R-516A as
acceptable, subject to use conditions, for use in new ice skating
rinks.
4. Why is EPA proposing these specific use conditions?
The use conditions identified in the proposed listings above are
explained in section II.H.1.
This proposal applies to end-uses covered by UL 60335-2-89,
including the SNAP ice skating rinks end-use. In addition, ASHRAE 15-
2022 applies to these refrigeration systems.
The standard UL 60335-2-89 discussed in section II.H indicates that
refrigerant charges greater than a specific amount (called
``m<INF>3</INF>'' in the standard and based on the refrigerant's LFL)
are beyond its scope and that national standards might apply, such as
ASHRAE 15-2022. Hence, EPA is proposing to require adherence to both
standards as use conditions for ice skating rinks, broadening the
coverage under this proposed rule

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