U.S. EPA announces final ‘Technology Transitions’ rule and proposed refrigerant management rule under AIM act

October 25, 2023

The U.S. Environmental Protection Agency (EPA) announced on October 6 its latest actions to phase down climate-damaging HFCs under the American Innovation and Manufacturing (AIM) Act, releasing a final “Technology Transitions” rule to accelerate the ongoing transition to more efficient and climate-safe technologies in new refrigeration, heating and cooling systems and other products by restricting the use of HFCs where alternatives are already available.

The final rule bans HFCs in certain new equipment and sets a limit on the GWP of the HFCs that can be used in each subsector, with compliance dates ranging from 2025 to 2028. It aligns closely with several petitions to replicate California’s HFC restrictions by setting GWP limits of 150 for many refrigeration uses, and 700 for air conditioning and heat pumps. The California regulations have spurred a significant uptick in the use of natural refrigerant-based alternatives like transcritical CO₂ (R744) systems and hydrocarbon cabinets in supermarkets in that state.

The rule applies to both imported and domestically manufactured products, which will “help ensure a level playing field for American businesses that are already transitioning to HFC alternatives,” said the EPA.

In addition, the EPA on October 6 announced a proposed rule to better manage and reuse existing HFCs, including by reducing wasteful leaks from equipment and supporting a growing U.S. industry for HFC recycling and reclamation. EPA will accept comments on the proposed rulemaking, _“Management of Certain Hydrofluorocarbons and Substitutes under Subsection (h) of the American Innovation and Manufacturing Act of 2020,” for 60 days after publication in the Federal Register and hold a public hearing.

Under the AIM Act, the EPA is also phasing down HFCs to achieve a 40% reduction of HFCs relative to baseline starting in 2024 and an 85% reduction by 2036. Recently, EPA issued HFC allowances, which allow companies to produce or import bulk HFCs for calendar year 2024 per the limits.

The EPA’s actions on October 6 followed by one day the announcement of a provisional agreement by Council of the EU and the European Parliament to phase down f-gases, putting into place the final pieces of the revised EU F-gas Regulation and setting the stage for the elimination of f-gases in the EU by 2050.

The new EPA’s moves also come one year after President Biden signed the U.S. ratification of the Kigali Amendment to the Montreal Protocol, the international agreement to phase down super-polluting HFCs and help avoid up to 0.5°C of global warming by 2100.



The Technology Transitions rule “sets an ambitious timetable for refrigerants used in heating and cooling equipment to be capped by their climate-damaging potential,” said Avipsa Mahapatra, Climate Campaign Director, Environmental Investigation Agency (EIA US). “Meanwhile, the proposed rule [on refrigerant management] ensures that the demand for ‘virgin’ HFCs is reduced by incentivizing their reuse. So we are turning off the faucet and mopping up the mess.”

Added Mahapatra: “This is a momentous week signaling the beginning of the end to our decades of reliance on these synthetic super pollutants.”

“We welcome EPA’s continued action to phase down HFCs, speed the transition to cost-effective alternatives, and ensure these harmful pollutants are reclaimed and recovered,” said Casey Katims, Executive Director of the U.S. Climate Alliance. “These rules build on the strong foundation Alliance states established and we look forward to working with EPA to continue to maximize the benefits for consumers and communities.”



EPA estimates that the Technology Transitions rule would provide additional cumulative greenhouse gas emissions reductions of at least 83 million metric tons of carbon dioxide equivalent (MMTCO₂e) from 2025 to 2050, a benefit of at least $3 billion. In addition to climate benefits, this final rule is estimated to provide $4.5 billion in savings for industry and consumers through 2050, largely from improved energy efficiency and lower cost refrigerants.

The proposed rule on an HFC emissions reduction and reclamation program is estimated to prevent at least an additional 142 million metric tons of CO₂e in HFC emissions over the same time, an incremental net benefit of at least $6.1 billion. Both actions will help unlock additional climate benefits and savings in addition to the national phasedown program, which is estimated to provide approximately $270 billion in benefits.

The proposed program to manage emissions reduction and reclamation of HFCs and their substitutes would help minimize HFC leaks across the lifespan of existing equipment, such as air conditioners and refrigeration systems, while also maximizing the reuse of existing HFCs. The proposed rule includes requirements for repairing leaky equipment (with no “trigger” leak rates), use of automatic leak detection systems on large refrigeration systems, use of reclaimed HFCs for certain applications, recovery of HFCs from cylinders before their disposal, and a container tracking system.

Notably, the EPA during the Trump administration rescinded a rule applying leak repair requirements to HFCs in addition to ozone-depleting substances; the proposed rule restores and expands those requirements, bringing a range of smaller equipment containing more than 15lbs of HFC refrigerants under their purview.

The proposed rule also contains a proposal for requiring the use of 100% reclaimed refrigerant in most new appliances and systems still containing HFCs beginning in 2028, ranging from new air conditioners and heat pumps to supermarkets and other commercial refrigeration equipment.

The proposed rule “will spur innovations to how cooling equipment is designed and how the entire U.S. industry and workforce tracks and handles refrigerants,” said Christina Starr, Senior Manager, EIA US. “It also incentivizes companies to take a truly cradle-to-grave approach in setting and meeting their climate targets.”

Details of Technology Transitions rule

According to the EPA’s Technology Transitions Fact Sheet, the final rule will restricts the sale, distribution, import, and export of new products containing high­er-GWP HFCs three years after the manufacture and import compliance dates “to allow for a sell-through period of previously manufactured or imported products.” This rule also restricts the installation of certain new systems by the designated compliance dates. Thus it distinguishes between “products” and “systems.”

The rule defines a product as “functional upon leaving a factory.” Examples of products include window air condi­tioning units, refrigerators, and stand-alone ice machines. By contrast, it defines a system as “assembled and charged in the field using multiple components.” Examples include supermarket refrigeration systems that include a centralized compressor room and mini-split air conditioners. Components include equipment such as compressors, condensers, and dis­play cabinets. In this rule, EPA is not restricting the manufacture, import, sale, distribution, or export of components that are used to repair existing RACHP systems.

This rule does not restrict the continued use of any existing products or RACHP systems.

“Allowing existing systems to continue to operate to the end of their useful life is important to ensuring a smooth transition in the phasedown of HFCs,” said the EPA. A product or system may be ser­viced and repaired throughout its useful life; this includes replacing components, as needed.

In this rule, EPA defines the distinction between maintenance of a system and installation of a new system. Specifically, the following actions, upon charging the system to full charge, are considered a new installation of a refrigeration, air-conditioning or heat pump system and subject to the relevant HFC use restrictions:

• Assembling a system for the first time from used or new components;
• Increasing the cooling capacity, in BTU per hour, of an existing system; or
• Replacing 75% or more of evaporators (by number) and 100% of the compressor racks, condensers, and connected evaporator loads of an existing system.

The following are a sample of some of the self-contained refrigeration, air-conditioning and heat pump product restrictions in the new Technology Transitions rule under the AIM Act, with GWP limit and manufacturer and import compliance date. A complete list can be found here.

• Retail food-refrigeration stand-alone units; 150 GWP; January 1, 2025
• Household refrigerators and freezers; 150 GWP; January 1, 2025
• Vending machines; 150 GWP, January 1, 2025
• Motor vehicle air conditioning (light-duty passenger vehicles); 150 GWP; Model year 2025, and no earlier than one year after publication in the Federal Register
• Stationary residential and light-commercial air conditioning and heat pumps (e.g., window units and portable room air-conditioning); 700 GWP, January 1, 2025

The following are a sample of some of the refrigeration, air-conditioning and heat pump system restrictions in the new Technology Transitions rule under the AIM Act, with GWP limit and installation compliance date. A complete list can be found here.

• Retail food supermarkets (with 200lbs/91kg or more of refrigerant charge, excluding high-temperature side of cascade system); 150 GWP; January 1, 2027
• Retail food remote condensing units (with 200lbs/91kg or more of refrigerant charge, excluding high-temperature side of cascade system); 150 GWP; January 1, 2026
• Cold-storage warehouses (with 200lbs/91kg or more of refrigerant charge, excluding high-temperature side of cascade system); 150 GWP; January 1, 2026
• Industrial process refrigeration not using chillers (with 200lbs/91kg or more of refrigerant charge, excluding high-temperature side of cascade system, and with temperature of the refrigerant entering the evaporator above -30°C/-22°F); 150 GWP; January 1, 2026
• Chillers (industrial process refrigeration with exiting fluid above -30°C/-22°F); 700 GWP; January 1, 2026)
• Chillers (comfort cooling); 700 GWP; January 1, 2025)
• Ice rinks; 700 GWP; January 1, 2025
• Data centers, computer room air-conditioning and information technology equipment cooling; 700 GWP; January 1, 2027
• Residential and light-commercial air-conditioning and heat pump systems; 700 GWP; January 1, 2025

In addition, for refrigerated road transport, systems with the following refrigerants will be banned as of January 1, 2025: R-402A, R-402B, R-404A, R-407B, R-408A, R-410B, R-417A, R-421A, R-421B, R-422A, R-422B, R-422C, R-422D, R-424A, R-428A, R-434A, R-438A, R-507A, R-125/290/134a/600a (55/1/42.5/1.5), RS-44 (2003 formulation), GHG-X5.

Details of proposed refrigerant management rule

The following are some of the provisions of the proposed refrigerant management rule under the AIM Act, and the proposed effective date. A complete list can be found here.

Leak repair

• For appliances containing 50lbs (23kg) or more of a refrigerant that contains an HFC or a substitute for an HFC with a GWP greater than 53; 60 days after final rule is published.
• For appliances containing between 15lbs (7kg) and 50lbs of a refrigerant that contains an HFC or a substitute for an HFC with a GWP greater than 53; one year after final rule is published.

Installation of automatic-leak-detection (ALD) systems

• For commercial refrigeration and industrial process refrigeration appliances that were installed prior to effective date of the final rule with a charge size of 1,500lbs (680kg) or more; within one year after the date of final rule publication
• For commercial refrigeration and industrial process refrigeration appliances that were installed on or after the effective date the final rule with a charge size of 1,500lbs or more; within 30 days of appliance installation.

Use of reclaimed HFCs

• For initial charge (installation) of certain equipment: residential and light commercial AC and heat pumps, cold storage warehouses, industrial process refrigeration, stand-alone retail food refrigeration, supermarket systems, refrigerated transport, automatic commercial ice makers; January 1, 2028.
• For servicing and/or repair of certain equipment: stand-alone retail food refrigeration supermarket systems, refrigerated transport, automatic commercial ice makers; January 1, 2028.