Efforts to limit the use of hydrofluorocarbons (HFCs) in cooling, refrigeration and foam blowing have encountered a legal setback in the United States. An August 8 decision from the U.S. Court of Appeals blocks the scheduled phase-out of HFC-based products with high global warming potential (GWP), ruling that the U.S. Environmental Protection Agency (EPA) lacks statutory authority for the regulatory approach it has taken. However, the presiding justices pointed to other potential paths to invoke an HFC prohibition.

Manufacturers of HFC-134a — a refrigerant and blowing agent with GWP 1,300 times greater than carbon dioxide — filed the legal challenge after the EPA designated it as an unacceptable substitute for ozone-depleting substances and established various deadlines for its elimination from newly manufactured products. This was in line with President Barack Obama’s 2013 climate action plan.

Arguments on both sides largely focused on the wording of the section of the U.S. Clean Air Act that governs the EPA’s listing or delisting of allowable products, known as the Significant New Alternatives Policy or SNAP program. Since the SNAP list’s original purpose was to target ozone-depleting substances, the challengers, Mexichem Fluor Inc. and Arkema Group, argued that they had replaced ozone-depleting substances with HFCs at a time when it was legal to do so and should not be retroactively compelled to replace them with a different non ozone-depleting substance. Two of the three presiding judges agreed with this interpretation.

“EPA’s authority to regulate ozone-depleting substances under Section 612 (of the Clean Air Act) and other statutes does not give EPA authority to order the replacement of substances that are not ozone depleting, but that contribute to climate change. Congress has not yet enacted general climate change legislation,” they state in their majority decision. “Under the Constitution, congressional inaction does not license an agency to take matters into its own hands, even to solve a pressing policy issue such as climate change…climate change is not a blank check for the President.”

Rather, the decision postulates the EPA could accomplish much the same ends if it undertakes the due process to retroactively disapprove HFCs or enacts a regulation under the Toxic Substances Control Act, which is within its statutory authority. “Of course, even if EPA concludes that it has cleared those hurdles, EPA’s conclusion many be subject to review in this Court in another case,” it notes.

Other prominent refrigerant manufacturers were on side with the EPA when the case was argued in February 2017. Honeywell and Chemours (formerly DuPont) were intervenors in the case, while representatives from the current U.S. administration also made presentations in favour of its predecessor’s initiative.

The United States continues to be a party to the Kigali amendment to the Montreal Protocol, which establishes a target for developed countries to reduce current levels of HFCs by 85 per cent  by 2036.