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Greenhouse Gases

EPA beefs up rules to curb HFC use

One final rule, one proposed rule seek to cap creation, emission of potent global warming hydrofluorocarbons

by Leigh Krietsch Boerner
October 12, 2023 | A version of this story appeared in Volume 101, Issue 34


Hand of car mechanic technician using a meter to check a car air conditioner system heat problem and fix repairing and filling air refrigerant.
Credit: Shutterstock
A mechanic uses a meter to check a car’s air conditioning system. The US Environmental Protection Agency has proposed a rule that includes the regulation of repairing leaky systems that use HFC refrigerants, including car air conditioners.

The US Environmental Protection Agency announced two new actions on Oct. 6 limiting the use and manufacture of hydrofluorocarbons, or HFCs. The first action is a final rule laying out timelines to cut the manufacture and use of HFCs. The second is a proposed rule to regulate emissions and support the reuse of existing HFCs.

HFCs are a class of compounds used in air conditioners, refrigerators, insulation foam, and other applications. Initially introduced by chemical makers as replacements for ozone–depleting chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs), HFCs were found to be potent greenhouse gases. Chemical companies such as Chemours and Honeywell are promoting hydrofluoroolefins as replacements for HFCs.

The final rule specifically restricts the use of HFCs with high global warming potential in new aerosols and foams and in refrigeration, air conditioning, and heat pump products and equipment. The rule supports the American Innovation and Manufacturing Act of 2020 goal to cut use of HFCs by 40% by 2024 and 85% by 2036. The EPA actions come a year after the US Senate voted to join the Kigali Amendment, an addendum to the Montreal Protocol to reduce the use and production of HFCs.

The proposed rule includes requirements to manage some HFCs that are already in use. It outlines approaches for leak repair on some appliances that use HFCs, tracking systems for HFC reuse, and standards for HFC recovery and recycling.

In a response to a request for comment, the Center for the Polyurethanes Industry, part of the American Chemistry Council, a trade group, says it supports the EPA’s final rule because it will create a federal standard and prevent “overburdensome requirements for manufacturers from varying state regulation.”

HFC emissions are tiny compared to those of carbon dioxide, but because of HFCs’ global warming potential, they account for fully 2% of total greenhouse gases on a CO2 basis. For example, the common refrigerant 1,1,1,2-tetrafluoroethane, known commercially as R-134a, is almost 1,500 times more potent a greenhouse gas than CO2.



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