40 CFR Appendix V to Subpart G of Part 82 - Appendix V to Subpart G of Part 82—Substitutes Subject to Use Restrictions and Unacceptable Substitutes Listed in the December 1, 2016, Final Rule, Effective January 3, 2017, and Listed in the June 13, 2024 Final Rule, Effective July 15, 2024

Appendix V to Subpart G of Part 82—Substitutes Subject to Use Restrictions and Unacceptable Substitutes Listed in the December 1, 2016, Final Rule, Effective January 3, 2017, and Listed in the June 13, 2024 Final Rule, Effective July 15, 2024

Refrigerants—Acceptable Subject to Use Conditions

End-use Substitute Decision Use conditions Further information
1. Commercial ice machines (self-contained) (new only) manufactured from January 3, 2017, and up to but not including 7/15/2024 Propane (R-290) Acceptable subject to use conditions This refrigerant may be used only in new equipment designed specifically and clearly identified for the refrigerant—i.e., this refrigerant may not be used as a conversion or “retrofit” refrigerant for existing equipment.
This refrigerant may be used only in self-contained commercial ice machines that meet requirements listed in Supplement SA to UL 563. 12, 5 In cases where this rule includes requirements more stringent than those in UL 563, the equipment must meet the requirements of the final rule in place of the requirements in the UL Standard.
The charge size must not exceed 150 g (5.29 oz) in each refrigerant circuit of a commercial ice machine.
As provided in clauses SA6.1.1 and SA6.1.2 of UL 563, the following markings must be attached at the locations provided and must be permanent:
(a) “DANGER—Risk of Fire or Explosion. Flammable Refrigerant Used. Do Not Use Mechanical Devices To Defrost Refrigerator. Do Not Puncture Refrigerant Tubing.” This marking must be provided on or near any evaporators that can be contacted by the consumer.
(b) “DANGER—Risk of Fire or Explosion. Flammable Refrigerant Used. To Be Repaired Only By Trained Service Personnel. Do Not Puncture Refrigerant Tubing.” This marking must be located near the machine compartment.
(c) “CAUTION—Risk of Fire or Explosion. Flammable Refrigerant Used. Consult Repair Manual/Owner's Guide Before Attempting To Service This Product. All Safety Precautions Must be Followed.” This marking must be located near the machine compartment.
(d) “CAUTION—Risk of Fire or Explosion. Dispose of Properly In Accordance With Federal Or Local Regulations. Flammable Refrigerant Used.” This marking must be provided on the exterior of the refrigeration equipment.
(e) “CAUTION—Risk of Fire or Explosion Due To Puncture Of Refrigerant Tubing; Follow Handling Instructions Carefully. Flammable Refrigerant Used.” This marking must be provided near all exposed refrigerant tubing.
All of these markings must be in letters no less than 6.4 mm ( 1/4 inch) high.
The equipment must have red Pantone® Matching System #185 marked pipes, hoses, or other devices through which the refrigerant passes, to indicate the use of a flammable refrigerant. This color must be applied at all service ports and other parts of the system where service puncturing or other actions creating an opening from the refrigerant circuit to the atmosphere might be expected and must extend a minimum of one (1) inch in both directions from such locations.		 Applicable OSHA requirements at 29 CFR part 1910 must be followed, including those at 29 CFR 1910.94 (ventilation), 1910.106 (flammable and combustible liquids), 1910.110 (storage and handling of liquefied petroleum gases), 1910.157 (portable fire extinguishers), and 1910.1000 (toxic and hazardous substances).
Proper ventilation should be maintained at all times during the manufacture and storage of equipment containing hydrocarbon refrigerants through adherence to good manufacturing practices as per 29 CFR 1910.106. If refrigerant levels in the air surrounding the equipment rise above one-fourth of the lower flammability limit, the space should be evacuated and re-entry should occur only after the space has been properly ventilated.
Technicians and equipment manufacturers should wear appropriate personal protective equipment, including chemical goggles and protective gloves, when handling propane. Special care should be taken to avoid contact with the skin since propane, like many refrigerants, can cause freeze burns on the skin.
A Class B dry powder type fire extinguisher should be kept nearby.
Technicians should only use spark-proof tools when working on equipment with propane.
Any recovery equipment used should be designed for flammable refrigerants.
Any refrigerant releases should be in a well-ventilated area, such as outside of a building.
Only technicians specifically trained in handling flammable refrigerants should service equipment containing propane. Technicians should gain an understanding of minimizing the risk of fire and the steps to use flammable refrigerants safely.
Room occupants should evacuate the space immediately following the accidental release of this refrigerant.
If a service port is added then, commercial ice machines or equipment using propane should have service aperture fittings that differ from fittings used in equipment or containers using non-flammable refrigerant. “Differ” means that either the diameter differs by at least 1/16 inch or the thread direction is reversed (i.e., right-handed vs. left-handed). These different fittings should be permanently affixed to the unit at the point of service and maintained until the end-of-life of the unit and should not be accessed with an adaptor.
2. Commercial ice machines (self-contained) (new only) manufactured on or after 7/15/2024, through September 29, 2024, or equipment manufactured on or after September 30, 2024, that remains unchanged, other than cosmetic changes, from an earlier model or design that was already certified to the UL 563 125 standard before September 30, 2024 Propane (R-290) Acceptable subject to use conditions This refrigerant may be used only in self-contained commercial ice machines that meet requirements in either:
1. Supplement SA to UL 563 125 and listing 1 of this table or
2. ASHRAE 15-2022, 17,8 UL 60335-2-89, 1,2,6 and listing 3 of this table.
3. Commercial ice machines (self-contained) (new only) manufacturedon or after September 30, 2024, except for equipment manufactured on or after September 30, 2024, that remains unchanged, other than cosmetic changes, from an earlier model or design that was already certified to the UL 563 125 standard before September 30, 2024 Propane (R-290) Acceptable subject to use conditions This refrigerant may be used only in new equipment specifically designed and clearly identified for the refrigerant (i.e., none of these substitutes may be used as a conversion or “retrofit” refrigerant for existing equipment designed for other refrigerants).
This refrigerant may be used in new commercial ice machines if and only if such equipment meets all requirements in ASHRAE 15-2022 1,7,8. In cases where this listing 3 includes requirements different than those of ASHRAE 15-2022 1,7,8 the appliance would need to meet the requirements of this listing in place of the requirements in ASHRAE 15-2022.
This refrigerant may only be used in commercial ice machines that meet all requirements in UL 60335-2-89, 1,2,6 except as provided otherwise in UL 60335-2-89, in ASHRAE 15-2022, or in this listing 3. In cases where this listing includes requirements more stringent than those of UL 60335-2-89, the appliance must meet the requirements of this listing 3 in place of the requirements in the UL 60335-2-89. Where similar requirements of ASHRAE 15-2022 and UL 60335-2-89 differ, the more stringent or conservative condition shall apply unless superseded by this listing 3.
The following markings must be attached at the locations provided and must be permanent:		 Applicable OSHA requirements at 29 CFR part 1910 must be followed, including those at 29 CFR 1910.94 (ventilation) and 1910.106 (flammable and combustible liquids), 1910.110 (storage and handling of liquefied petroleum gases), and 1910.1000 (toxic and hazardous substances).
Proper ventilation should be maintained at all times during the manufacture and storage of equipment containing flammable refrigerants through adherence to good manufacturing practices as per 29 CFR 1910.106. If refrigerant levels in the air surrounding the equipment rise above one-fourth of the lower flammability limit, the space should be evacuated, and reentry should occur only after the space has been properly ventilated.
Technicians and equipment manufacturers should wear appropriate personal protective equipment, including chemical goggles and protective gloves, when handling flammable refrigerants. Special care should be taken to avoid contact with the skin which, like many refrigerants, can cause freeze burns on the skin.
A class B dry powder type fire extinguisher should be kept nearby.
Technicians should only use spark-proof tools when working on air conditioning equipment with flammable refrigerants.
(a) On the outside of the equipment: “DANGER—Risk of Fire Or Explosion. Flammable Refrigerant Used. To Be Repaired Only By Trained Service Personnel. Do Not Puncture Refrigerant Tubing.”
(b) On the outside of the equipment: “WARNING—Risk of Fire OR Explosion. Dispose of Properly In Accordance With Federal Or Local Regulations. Flammable Refrigerant Used.”
(c) On the inside of the equipment near the compressor: “DANGER—Risk of Fire Or Explosion. Flammable Refrigerant Used. Consult Repair Manual/Owner's Guide Before Attempting to Service This Product. All Safety Precautions Must be Followed.”
(d) For any equipment pre-charged at the factory, on the equipment packaging or on the outside of the equipment: “DANGER—Risk of Fire or Explosion due to Flammable Refrigerant Used. Follow Handling Instructions Carefully in Compliance with National Regulations”
a. If the equipment is delivered packaged, this label shall be applied on the packaging.
b. If the equipment is not delivered packaged, this label shall be applied on the outside of the equipment near the control panel or nameplate.
(e) On indoor units near the nameplate:		 Any recovery equipment used should be designed for flammable refrigerants. Only technicians specifically trained in handling flammable refrigerants should service refrigeration equipment containing this refrigerant. Technicians should gain an understanding of minimizing the risk of fire and the steps to use flammable refrigerants safely.
Room occupants should evacuate the space immediately following the accidental release of this refrigerant.
Personnel commissioning, maintaining, repairing, decommissioning and disposing of appliances with this refrigerant should obtain training and follow practices consistent with Annex 101.DVT of UL 60355-2-89. 1,2,5
Department of Transportation requirements for transport of flammable gases must be followed.
Flammable refrigerants being recovered or otherwise disposed of from ice machine appliances are likely to be hazardous waste under the Resource Conservation and Recovery Act (RCRA) (see 40 CFR parts 260 through 270).
a. At the top of the marking: “Minimum Installation Height, X m (W ft)”. This marking is only required if required by UL 60335-2-89. The terms “X” and “W” shall be replaced by the numeric height as calculated per UL 60335-2-89. Note that the formatting here is slightly different than the UL Standard; specifically, the height in Inch-Pound units is placed in parentheses and the word “and” has been replaced by the opening parenthesis.
b. Immediately below (a) above or at the top of the marking if (a) is not required: “Minimum room area (operating or storage), Y m 2 (Z ft 2)”. The terms “Y” and “Z” shall be replaced by the numeric area as calculated per UL 60335-2-89. Note that the formatting here is slightly different than UL 60335-2-89; specifically, the area in Inch-Pound units is placed in parentheses and the word “and” has been replaced by the opening parenthesis.
(f) For non-fixed equipment, on the outside of the appliance: “WARNING—Risk of Fire or Explosion—Store in a well-ventilated room without continuously operating flames or other potential ignition.”
(g) For fixed equipment that is ducted, near the nameplate: “WARNING—Risk of Fire Or Explosion—Auxiliary devices which may be ignition sources shall not be installed in the ductwork, other than auxiliary devices listed for use with the specific appliance. See instructions.”
(h) All of these markings must be in letters no less than 6.4 mm ( 1/4 inch) high.
The equipment must have red Pantone® Matching System #185 or RAL 3020 marked service ports, pipes, hoses, or other devices through which the refrigerant passes, to indicate the use of a flammable refrigerant. This color must be applied at all service ports and other parts of the system where service puncturing or other actions creating an opening from the refrigerant circuit to the atmosphere might be expected and must extend a minimum of one (1) inch (25 mm) in both directions from such locations and shall be replaced if removed.
In addition to or instead of the markings described in Clause 7.6DV D1 of UL 60335-2-89, the equipment may display the Globally Harmonized System of Classification and Labelling of Chemicals GHS warning symbol for hazard category 1 flammable gases (black flame on a white background in a diamond with equal length sides with a red border), as defined in Chapter 2.2, Flammable Gasses, and Annex 1, Classification and Labelling Summary Tables, of ST/SG/AC.10/30/Rev.9, Global Harmonized System (GHS) of Classification and Labelling of Chemicals, Ninth revised edition 111,12:
• Outside of the equipment (label (a));
• on the appliance packaging for a factory-charged unit or adjacent to the control panel or nameplate of a unit charged in place (label (d)); and
• in a location visible when accessing a service port and where service puncturing or otherwise creating an opening from the refrigerant circuit to the atmosphere might be expected (e.g., process tubes) (service label).
The perpendicular height of the diamond containing the GHS warning symbol for hazard category 1 flammable gases shall be at least 15 mm ( 9/16 in). In addition, next to the GHS warning symbol for hazard category 1 flammable gases must be text of the refrigerant safety class of the refrigerant according to ASHRAE 34-2022, 17910 in letters at least one-third the height of the diamond symbol.
4. Very low temperature refrigeration equipment (new only) Propane (R-290) Acceptable subject to use conditions As of January 3, 2017:
This refrigerant may be used only in new equipment designed specifically and clearly identified for the refrigerant—i.e., this refrigerant may not be used as a conversion or “retrofit” refrigerant for existing equipment.
This refrigerant may only be used in equipment that meets requirements in Supplement SB to UL 471. 124 In cases where this listing 4 of this table includes requirements more stringent than those of UL 471, the appliance must meet the requirements of this listing 4 of this table in place of the requirements in UL 471.
The charge size for the equipment must not exceed 150 grams (5.29 ounces) in each refrigerant circuit of the very low temperature refrigeration equipment.
As provided in clauses SB6.1.2 to SB6.1.5 of UL 471, the following markings must be attached at the locations provided and must be permanent:		 Applicable OSHA requirements at 29 CFR part 1910 must be followed, including those at 29 CFR 1910.94 (ventilation) and 1910.106 (flammable and combustible liquids), 1910.110 (storage and handling of liquefied petroleum gases), 1910.157 (portable fire extinguishers), and 1910.1000 (toxic and hazardous substances).
Proper ventilation should be maintained at all times during the manufacture and storage of equipment containing hydrocarbon refrigerants through adherence to good manufacturing practices as per 29 CFR 1910.106. If refrigerant levels in the air surrounding the equipment rise above one-fourth of the lower flammability limit, the space should be evacuated and re-entry should occur only after the space has been properly ventilated.
(a) “DANGER—Risk of Fire or Explosion. Flammable Refrigerant Used. Do Not Use Mechanical Devices To Defrost Refrigerator. Do Not Puncture Refrigerant Tubing.” This marking must be provided on or near any evaporators that can be contacted by the consumer.
(b) “DANGER—Risk of Fire or Explosion. Flammable Refrigerant Used. To Be Repaired Only By Trained Service Personnel. Do Not Puncture Refrigerant Tubing.” This marking must be located near the machine compartment.
(c) “CAUTION—Risk of Fire or Explosion. Flammable Refrigerant Used. Consult Repair Manual/Owner's Guide Before Attempting To Service This Product. All Safety Precautions Must be Followed.” This marking must be located near the machine compartment.
(d) “CAUTION—Risk of Fire or Explosion. Dispose of Properly In Accordance With Federal Or Local Regulations. Flammable Refrigerant Used.” This marking must be provided on the exterior of the refrigeration equipment.
(e) “CAUTION—Risk of Fire or Explosion Due To Puncture Of Refrigerant Tubing; Follow Handling Instructions Carefully. Flammable Refrigerant Used.” This marking must be provided near all exposed refrigerant tubing.
All of these markings must be in letters no less than 6.4 mm ( 1/4 inch) high.
The equipment must have red Pantone® Matching System #185 marked pipes, hoses, or other devices through which the refrigerant passes, to indicate the use of a flammable refrigerant. This color must be applied at all service ports and other parts of the system where service puncturing or other actions creating an opening from the refrigerant circuit to the atmosphere might be expected and must extend a minimum of one (1) inch in both directions from such locations.		 Technicians and equipment manufacturers should wear appropriate personal protective equipment, including chemical goggles and protective gloves, when handling propane. Special care should be taken to avoid contact with the skin since propane, like many refrigerants, can cause freeze burns on the skin.
A Class B dry powder type fire extinguisher should be kept nearby.
Technicians should only use spark-proof tools when working on equipment with flammable refrigerants.
Any recovery equipment used should be designed for flammable refrigerants.
Any refrigerant releases should be in a well-ventilated area, such as outside of a building.
Only technicians specifically trained in handling flammable refrigerants should service equipment containing propane. Technicians should gain an understanding of minimizing the risk of fire and the steps to use flammable refrigerants safely
Room occupants should evacuate the space immediately following the accidental release of this refrigerant.
If a service port is added, then very low temperature equipment using propane should have service aperture fittings that differ from fittings used in equipment or containers using non-flammable refrigerant. “Differ” means that either the diameter differs by at least 1/16 inch or the thread direction is reversed (i.e., right-handed vs. left-handed). These different fittings should be permanently affixed to the unit at the point of service and maintained until the end-of-life of the unit, and should not be accessed with an adaptor.
Very low temperature equipment using propane may also use another acceptable refrigerant substitute in a separate refrigerant circuit or stage (e.g., one temperature stage with propane and a second stage with ethane).
5. Water coolers (new only) Propane (R-290) Acceptable subject to use conditions This refrigerant may be used only in new equipment designed specifically and clearly identified for the refrigerant—i.e., this refrigerant may not be used as a conversion or “retrofit” refrigerant for existing equipment.
This refrigerant may be used only in water coolers that meet requirements listed in Supplement SB to UL 399 123 In cases where this listing 5 includes requirements more stringent than those of UL 399, the appliance must meet the requirements of this listing 5 in place of the requirements in UL 399.
The charge size must not exceed 60 grams (2.12 ounces) per refrigerant circuit in the water cooler.
The equipment must have red Pantone® Matching System #185 marked pipes, hoses, or other devices through which the refrigerant passes, to indicate the use of a flammable refrigerant. This color must be applied at all service ports and other parts of the system where service puncturing or other actions creating an opening from the refrigerant circuit to the atmosphere might be expected and must extend a minimum of one (1) inch in both directions from such locations.
As provided in clauses SB6.1.2 to SB6.1.5 of UL 399, the following markings must be attached at the locations provided and must be permanent:		 Applicable OSHA requirements at 29 CFR part 1910 must be followed, including those at 29 CFR 1910.94 (ventilation) and 1910.106 (flammable and combustible liquids), 1910.110 (storage and handling of liquefied petroleum gases), 1910.157 (portable fire extinguishers), and 1910.1000 (toxic and hazardous substances).
Proper ventilation should be maintained at all times during the manufacture and storage of equipment containing hydrocarbon refrigerants through adherence to good manufacturing practices as per 29 CFR 1910.106. If refrigerant levels in the air surrounding the equipment rise above one-fourth of the lower flammability limit, the space should be evacuated and re-entry should occur only after the space has been properly ventilated.
Technicians and equipment manufacturers should wear appropriate personal protective equipment, including chemical goggles and protective gloves, when handling propane. Special care should be taken to avoid contact with the skin since propane, like many refrigerants, can cause freeze burns on the skin.
A Class B dry powder type fire extinguisher should be kept nearby.
Technicians should only use spark-proof tools when working on equipment with flammable refrigerants.
(a) “DANGER—Risk of Fire or Explosion. Flammable Refrigerant Used. Do Not Use Mechanical Devices To Defrost Refrigerator. Do Not Puncture Refrigerant Tubing.” This marking must be provided on or near any evaporators that can be contacted by the consumer.
(b) “DANGER—Risk of Fire or Explosion. Flammable Refrigerant Used. To Be Repaired Only By Trained Service Personnel. Do Not Puncture Refrigerant Tubing.” This marking must be located near the machine compartment.
(c) “CAUTION—Risk of Fire or Explosion. Flammable Refrigerant Used. Consult Repair Manual/Owner's Guide Before Attempting To Service This Product. All Safety Precautions Must be Followed.” This marking must be located near the machine compartment.
(d) “CAUTION—Risk of Fire or Explosion. Dispose of Properly In Accordance With Federal Or Local Regulations. Flammable Refrigerant Used.” This marking must be provided on the exterior of the refrigeration equipment.
(e) “CAUTION—Risk of Fire or Explosion Due To Puncture Of Refrigerant Tubing; Follow Handling Instructions Carefully. Flammable Refrigerant Used.” This marking must be provided near all exposed refrigerant tubing.		 Any recovery equipment used should be designed for flammable refrigerants.
Any refrigerant releases should be in a well-ventilated area, such as outside of a building.
Only technicians specifically trained in handling flammable refrigerants should service equipment containing propane. Technicians should gain an understanding of minimizing the risk of fire and the steps to use flammable refrigerants safely.
Room occupants should evacuate the space immediately following the accidental release of this refrigerant.
If a service port is added, then water coolers or equipment using propane should have service aperture fittings that differ from fittings used in equipment or containers using non-flammable refrigerant. “Differ” means that either the diameter differs by at least 1/16 inch or the thread direction is reversed (i.e., right-handed vs. left-handed). These different fittings should be permanently affixed to the unit at the point of service and maintained until the end-of-life of the unit, and should not be accessed with an adaptor.

1 The Director of the Federal Register approves this incorporation by reference (5 U.S.C. 552(a) and 1 CFR part 51). You may inspect a copy at the U.S. EPA or at the National Archives and Records Administration (NARA). Contact the U.S. EPA at: EPA Docket Center, WJC West Building, Room 3334, 1301 Constitution Avenue NW, Washington, DC 20004, www.epa.gov/dockets; (202) 202-1744. For information on the availability of this material at NARA, visit www.archives.gov/federal-register/cfr/ibr-locations or email fr.inspection@nara.gov.

2 You may obtain the UL material from: Underwriters Laboratories Inc. (UL) COMM 2000; 151 Eastern Avenue; Bensenville, IL 60106; phone: 1-888-853-3503 in the U.S. or Canada (other countries +1-415-352-2168); email: orders@shopulstandards.com; website: https://ulstandards.ul.com or www.shopulstandards.com.

3 UL 399, Standard for Safety: Drinking Water Coolers- Supplement SB: Requirements for Drinking Water Coolers Employing a Flammable Refrigerant in the Refrigerating System, 7th edition, dated August 22, 2008, including revisions through October 17, 2013.

4 UL 471, Standard for Safety: Commercial Refrigerators and Freezers. Supplement SB: Requirements for Refrigerators and Freezers Employing a Flammable Refrigerant in the Refrigerating System, 10th edition, dated November 24, 2010.

5 UL 563, Standard for Safety: Ice Makers. Supplement SA: Requirements for Ice Makers Employing a Flammable Refrigerant in the Refrigerating System, 8th edition, dated July 31, 2009, including revisions through November 29, 2013.

6 UL 60335-2-89, Standard for Safety for Household and Similar Electrical Appliances—Safety—Part 2-89: Particular Requirements for Commercial Refrigerating Appliances, 2nd edition, dated October 27, 2021.

7 You may obtain the ANSI/ASHRAE material from: American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE), 180 Technology Parkway NW, Peachtree Corners, Georgia 30092; phone: 1-800-527-4723 or 1-404-636-8400 in the U.S. or Canada; email: cservice@ashrae.org; website: https://w0ww.ashrae.org/technical-resources/bookstore/ashrae-refrigeration-resources.

8 ANSI/ASHRAE Standard 15-2022. Safety Standard for Refrigeration Systems, copyright 2022,

9 ANSI/ASHRAE Standard 34-2022. Designation and Safety Classification of Refrigerants, copyright 2022.

10 ANSI/ASHRAE Addendum a to ANSI/ASHRAE Standard 34-2022, Designation and Safety Classification of Refrigerants, ANSI-/ASHRAE-approved December 20, 2022.

11 You may obtain the UN material from the United Nations Publications section at: https://shop.un.org/books/global-harmon-syst-class-9-92280; by mail: United Nations Publications Customer Service, PO Box 960, Herndon, VA 20172; phone: 1-703-661-1571; email: order@un.org.

12 ST/SG/AC.10/30/Rev.9, Global Harmonized System (GHS) of Classification and Labelling of Chemicals, Ninth revised edition, copyright 2021; Chapter 2.2, Flammable Gasses, and Annex 1, Classification and Labelling Summary Tables.

Refrigerants—Substitutes Acceptable Subject to Narrowed Use Limits

End-use Substitutes Decision Narrowed use limits Further information
Centrifugal chillers (new only) HFC-134a Acceptable subject to narrowed use limits Acceptable after January 1, 2024, only in military marine vessels where reasonable efforts have been made to ascertain that other alternatives are not technically feasible due to performance or safety requirements Users are required to document and retain the results of their technical investigation of alternatives for the purpose of demonstrating compliance. Information should include descriptions of:
• Application in which the substitute is needed;
• Substitutes examined and rejected;
• Reason for rejection of other alternatives, e.g., performance, technical or safety standards; and/or
• Anticipated date other substitutes will be available and qualified and projected time for switching.
Centrifugal chillers (new only) HFC-134a and R-404A Acceptable subject to narrowed use limits Acceptable after January 1, 2024, only in human-rated spacecraft and related support equipment where reasonable efforts have been made to ascertain that other alternatives are not technically feasible due to performance or safety requirements Users are required to document and retain the results of their technical investigation of alternatives for the purpose of demonstrating compliance. Information should include descriptions of:
• Application in which the substitute is needed;
• Substitutes examined and rejected;
• Reason for rejection of other alternatives, e.g., performance, technical or safety standards; and/or
• Anticipated date other substitutes will be available and qualified and projected time for switching.
Positive displacement chillers (new only) HFC-134a Acceptable subject to narrowed use limits Acceptable after January 1, 2024, only in military marine vessels where reasonable efforts have been made to ascertain that other alternatives are not technically feasible due to performance or safety requirements Users are required to document and retain the results of their technical investigation of alternatives for the purpose of demonstrating compliance. Information should include descriptions of:
• Application in which the substitute is needed;
• Substitutes examined and rejected;
• Reason for rejection of other alternatives, e.g., performance, technical or safety standards; and/or
• Anticipated date other substitutes will be available and qualified and projected time for switching.
Positive displacement chillers (new only) HFC-134a and R-404A Acceptable subject to narrowed use limits Acceptable after January 1, 2024, only in human-rated spacecraft and related support equipment where reasonable efforts have been made to ascertain that other alternatives are not technically feasible due to performance or safety requirements Users are required to document and retain the results of their technical investigation of alternatives for the purpose of demonstrating compliance. Information should include descriptions of:
• Application in which the substitute is needed;
• Substitutes examined and rejected;
• Reason for rejection of other alternatives, e.g., performance, technical or safety standards; and/or
• Anticipated date other substitutes will be available and qualified and projected time for switching.

Refrigerants—Unacceptable Substitutes

End-use Substitutes Decision Further information
Centrifugal chillers (new only) FOR12A, FOR12B, HFC-134a, HFC-227ea, HFC-236fa, HFC-245fa, R-125/134a/600a (28.1/70/1.9), R-125/290/134a/600a (55.0/1.0/42.5/1.5), R-404A, R-407C, R-410A, R-410B, R-417A, R-421A, R-422B, R-422C, R-422D, R-423A, R-424A, R-434A, R-438A, R-507A, RS-44 (2003 composition), and THR-03 Unacceptable as of January 1, 2024 except where allowed under a narrowed use limit These refrigerants have GWPs ranging from approximately 900 to 9,810. Other alternatives will be available for this end-use with lower overall risk to human health and the environment by the status change date.
Centrifugal chillers (new only) Propylene (R-1270) and R-443A Unacceptable as of January 3, 2017 These refrigerants are highly photochemically reactive in the lower atmosphere and may deteriorate local air quality (that is, may increase ground level ozone). Other alternatives are available for this end-use with lower overall risk to human health and the environment.
Cold storage warehouses (new only) HFC-227ea, R-125/290/134a/600a (55.0/1.0/42.5/1.5), R-404A, R-407A, R-407B, R-410A, R-410B, R-417A, R-421A, R-421B, R-422A, R-422B, R-422C, R-422D, R-423A, R-424A, R-428A, R-434A, R-438A, R-507A, and RS-44 (2003 composition) Unacceptable as of January 1, 2023 These refrigerants have GWPs ranging from approximately 2,090 to 3,990. Other alternatives will be available for this end-use with lower overall risk to human health and the environment by the status change date.
Cold storage warehouses (new only) Propylene (R-1270) and R-443A Unacceptable as of January 3, 2017 These refrigerants are highly photochemically reactive in the lower atmosphere and may deteriorate local air quality (that is, may increase ground level ozone). Other alternatives are available for this end-use with lower overall risk to human health and the environment.
Household refrigerators and freezers (new only) FOR12A, FOR12B, HFC-134a, KDD6, R-125/290/134a/600a (55.0/1.0/42.5/1.5), R-404A, R-407C, R-407F, R-410A, R-410B, R-417A, R-421A, R-421B, R-422A, R-422B, R-422C, R-422D, R-424A, R-426A, R-428A, R-434A, R-437A, R-438A, R-507A, RS-24 (2002 formulation), RS-44 (2003 formulation), SP34E, and THR-03 Unacceptable as of January 1, 2021 These refrigerants have GWPs ranging from approximately 900 to 3,985. Other alternatives will be available for this end-use with lower overall risk to human health and the environment by the status change date.
Positive displacement chillers (new only) FOR12A, FOR12B, HFC-134a, HFC-227ea, KDD6, R-125/134a/600a (28.1/70/1.9), R-125/290/134a/600a (55.0/1.0/42.5/1.5), R-404A, R-407C, R-410A, R-410B, R-417A, R-421A, R-422B, R-422C, R-422D, R-424A, R-434A, R-437A, R-438A, R-507A, RS-44 (2003 composition), SP34E, and THR-03 Unacceptable as of January 1, 2024 except where allowed under a narrowed use limit These refrigerants have GWPs ranging from approximately 900 to 3,985. Other alternatives will be available for this end-use with lower overall risk to human health and the environment by the status change date.
Positive displacement chillers (new only) Propylene (R-1270) and R-443A Unacceptable as of January 3, 2017 These refrigerants are highly photochemically reactive in the lower atmosphere and may deteriorate local air quality (that is, may increase ground level ozone). Other alternatives are available for this end-use with lower overall risk to human health and the environment.
Residential and light commercial air conditioning and heat pumps (new only) Propylene (R-1270) and R-443A Unacceptable as of January 3, 2017 These refrigerants are highly photochemically reactive in the lower atmosphere and may deteriorate local air quality (that is, may increase ground level ozone). Other alternatives are available for this end-use with lower overall risk to human health and the environment.
Residential and light commercial air conditioning—unitary split AC systems and heat pumps (retrofit only) All refrigerants identified as flammability Class 3 in ANSI/ASHRAE Standard 34-2013 1 2 3
All refrigerants meeting the criteria for flammability Class 3 in ANSI/ASHRAE Standard 34-2013. This includes, but is not limited to, refrigerant products sold under the names R-22a, 22a, Blue Sky 22a refrigerant, Coolant Express 22a, DURACOOL-22a, EC-22, Ecofreeez EF-22a, Envirosafe 22a, ES-22a, Frost 22a, HC-22a, Maxi-Fridge, MX-22a, Oz-Chill 22a, Priority Cool, and RED TEK 22a		 Unacceptable as of January 3, 2017 These refrigerants are highly flammable and present a flammability risk when used in equipment designed for nonflammable refrigerants. Other alternatives are available for this end-use with lower overall risk to human health and the environment.
Retail food refrigeration (refrigerated food processing and dispensing equipment) (new only) HFC-227ea, KDD6, R-125/290/134a/600a (55.0/1.0/42.5/1.5), R-404A, R-407A, R-407B, R-407C, R-407F, R-410A, R-410B, R-417A, R-421A, R-421B, R-422A, R-422B, R-422C, R-422D, R-424A, R-428A, R-434A, R-437A, R-438A, R-507A, RS-44 (2003 formulation) Unacceptable as of January 1, 2021 These refrigerants have GWPs ranging from approximately 1,770 to 3,990. Other alternatives will be available for this end-use with lower overall risk to human health and the environment by the status change date.

1 The Director of the Federal Register approves this incorporation by reference (5 U.S.C. 552(a) and 1 CFR part 51). You may inspect a copy at U.S. EPA's Air and Radiation Docket; EPA West Building, Room 3334, 1301 Constitution Ave. NW., Washington, DC or at the National Archives and Records Administration (NARA). For questions regarding access to this standard, the telephone number of EPA's Air and Radiation Docket is 202-566-1742. For information on the availability of this material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.

2 You may obtain this material from: American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) 6300 Interfirst Drive, Ann Arbor, MI 48108; 1-800-527-4723 in the U.S. or Canada; http://www.techstreet.com/ashrae/ashrae_standards.html?ashrae_auth_token=.

3 ANSI/ASHRAE Standard 34-2013, Designation and Safety Classification of Refrigerants, 2013.

Foam Blowing Agents—Substitutes Acceptable Subject to Narrowed Use Limits

End-use Substitutes Decision Narrowed use limits Further information
Rigid PU: Spray foam—high-pressure two-component HFC-134a, HFC-245fa, and blends thereof; blends of HFC-365mfc with at least four percent HFC-245fa, and commercial blends of HFC-365mfc with seven to 13 percent HFC-227ea and the remainder HFC-365mfc; and Formacel TI Acceptable subject to narrowed use limits Acceptable from January 1, 2020, until January 1, 2025, only in military or space- and aeronautics-related applications where reasonable efforts have been made to ascertain that other alternatives are not technically feasible due to performance or safety requirements
Closed cell foam products and products containing closed cell foams manufactured with these substitutes on or before January 1, 2025, may be used after that date		 Users are required to document and retain the results of their technical investigation of alternatives for the purpose of demonstrating compliance. Information should include descriptions of:
• Process or product in which the substitute is needed;
• Substitutes examined and rejected;
• Reason for rejection of other alternatives, e.g., performance, technical or safety standards; and/or
• Anticipated date other substitutes will be available and projected time for switching.
Rigid PU: Spray foam—low-pressure two-component HFC-134a, HFC-245fa, and blends thereof; blends of HFC-365mfc with at least four percent HFC-245fa, and commercial blends of HFC-365mfc with seven to 13 percent HFC-227ea and the remainder HFC-365mfc; and Formacel TI Acceptable subject to narrowed use limits Acceptable from January 1, 2021, until January 1, 2025, only in military or space- and aeronautics-related applications where reasonable efforts have been made to ascertain that other alternatives are not technically feasible due to performance or safety requirements
Low pressure two-component spray foam kits manufactured with these substitutes on or before January 1, 2025, for military or space- and aeronautics-related applications may be used after that date		 Users are required to document and retain the results of their technical investigation of alternatives for the purpose of demonstrating compliance. Information should include descriptions of:
• Process or product in which the substitute is needed;
• Substitutes examined and rejected;
• Reason for rejection of other alternatives, e.g., performance, technical or safety standards; and/or
• Anticipated date other substitutes will be available and projected time for switching.

Foam Blowing Agents—Unacceptable Substitutes

End-use Substitutes Decision Further information
Flexible PU Methylene chloride Unacceptable as of January 3, 2017 Methylene chloride is a carcinogen and may present a toxicity risk. Other alternatives are available for this end-use with lower overall risk to human health and the environment.
Rigid PU: Spray foam—one component foam sealants HFC-134a, HFC-245fa, and blends thereof; blends of HFC-365mfc with at least four percent HFC-245fa, and commercial blends of HFC-365mfc with seven to 13 percent HFC-227ea and the remainder HFC-365mfc; and Formacel TI Unacceptable as of January 1, 2020
One-component foam sealant cans manufactured with these substitutes on or before January 1, 2020, may be used after that date		 These foam blowing agents have GWPs ranging from higher than 730 to approximately 1,500. Other alternatives will be available for this end-use with lower overall risk to human health and the environment by the status change date.
Rigid PU: Spray foam—high-pressure two-component HFC-134a, HFC-245fa, and blends thereof; blends of HFC-365mfc with at least four percent HFC-245fa, and commercial blends of HFC-365mfc with seven to 13 percent HFC-227ea and the remainder HFC-365mfc; and Formacel TI Unacceptable as of January 1, 2020, except where allowed under a narrowed use limit. Closed cell foam products and products containing closed cell foams manufactured with these substitutes on or before January 1, 2020, may be used after that date These foam blowing agents have GWPs ranging from higher than 730 to approximately 1,500. Other alternatives will be available for this end-use with lower overall risk to human health and the environment by the status change date.
Rigid PU: Spray foam—low-pressure two-component HFC-134a, HFC-245fa, and blends thereof; blends of HFC-365mfc with at least four percent HFC-245fa, and commercial blends of HFC-365mfc with seven to 13 percent HFC-227ea and the remainder HFC-365mfc; and Formacel TI Unacceptable as of January 1, 2021, except where allowed under a narrowed use limit
Low pressure two-component spray foam kits manufactured with these substitutes on or before January 1, 2025, may be used after that date		 These foam blowing agents have GWPs ranging from higher than 730 to approximately 1,500. Other alternatives will be available for this end-use with lower overall risk to human health and the environment by the status change date.

Fire Suppression and Explosion Protection Agents—Acceptable Subject to Use Conditions

End-use Substitute Decision Use conditions Further information
Streaming 2-BTP Acceptable, subject to use conditions As of January 3, 2017, acceptable only for use in handheld extinguishers in aircraft This fire suppressant has a relatively low GWP of 0.23-0.26 and a short atmospheric lifetime of approximately seven days.
This agent is subject to requirements contained in a Toxic Substance Control Act (TSCA) section 5(e) Consent Order and any subsequent TSCA section 5(a)(2) Significant New Use Rule (SNUR).
For establishments manufacturing, installing and maintaining handheld extinguishers using this agent:
(1) Use of this agent should be used in accordance with the latest edition of NFPA Standard 10 for Portable Fire Extinguishers;
(2) In the case that 2-BTP is inhaled, person(s) should be immediately removed and exposed to fresh air; if breathing is difficult, person(s) should seek medical attention;
(3) Eye wash and quick drench facilities should be available. In case of ocular exposure, person(s) should immediately flush the eyes, including under the eyelids, with fresh water and move to a non-contaminated area;
(4) Exposed person(s) should remove all contaminated clothing and footwear to avoid irritation, and medical attention should be sought if irritation develops or persists;
(5) Although unlikely, in case of ingestion of 2-BTP, the person(s) should consult a physician immediately;
(6) Manufacturing space should be equipped with specialized engineering controls and well ventilated with a local exhaust system and low-lying source ventilation to effectively mitigate potential occupational exposure; regular testing and monitoring of the workplace atmosphere should be conducted;
(7) Employees responsible for chemical processing should wear the appropriate PPE, such as protective gloves, tightly sealed goggles, protective work clothing, and suitable respiratory protection in case of accidental release or insufficient ventilation;
(8) All spills should be cleaned up immediately in accordance with good industrial hygiene practices; and
(9) Training for safe handling procedures should be provided to all employees that would be likely to handle containers of the agent or extinguishing units filled with the agent.
Total flooding 2-BTP Acceptable, subject to use conditions As of January 3, 2017, acceptable only for use in engine nacelles and auxiliary power units on aircraft This fire suppressant has a relatively low GWP of 0.23-0.26 and a short atmospheric lifetime of approximately seven days.
This agent is subject to requirements contained in a TSCA section 5(e) Consent Order and any subsequent TSCA section 5(a)(2) SNUR.
For establishments manufacturing, installing, and servicing engine nacelles and auxiliary power units on aircraft using this agent:
(1) This agent should be used in accordance with the safety guidelines in the latest edition of the National Fire Protection Association (NFPA) 2001 Standard for Clean Agent Fire Extinguishing Systems;
(2) In the case that 2-BTP is inhaled, person(s) should be immediately removed and exposed to fresh air; if breathing is difficult, person(s) should seek medical attention;
(3) Eye wash and quick drench facilities should be available. In case of ocular exposure, person(s) should immediately flush the eyes, including under the eyelids, with fresh water and move to a non-contaminated area.
(4) Exposed person(s) should remove all contaminated clothing and footwear to avoid irritation, and medical attention should be sought if irritation develops or persists;
(5) Although unlikely, in case of ingestion of 2-BTP, the person(s) should consult a physician immediately;
(6) Manufacturing space should be equipped with specialized engineering controls and well ventilated with a local exhaust system and low-lying source ventilation to effectively mitigate potential occupational exposure; regular testing and monitoring of the workplace atmosphere should be conducted;
(7) Employees responsible for chemical processing should wear the appropriate PPE, such as protective gloves, tightly sealed goggles, protective work clothing, and suitable respiratory protection in case of accidental release or insufficient ventilation;
(8) All spills should be cleaned up immediately in accordance with good industrial hygiene practices;
(9) Training for safe handling procedures should be provided to all employees that would be likely to handle containers of the agent or extinguishing units filled with the agent;
(10) Safety features that are typical of total flooding systems such as pre-discharge alarms, time delays, and system abort switches should be provided, as directed by applicable OSHA regulations and NFPA standards; use of this agent should also conform to relevant OSHA requirements, including 29 CFR 1910, subpart L, sections 1910.160 and 1910.162.
[81 FR 86889, Dec. 1, 2016, as amended at 89 FR 50474, June 13, 2024]