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  • John Tinsley

A guide to transition refrigerants

Who is required to use transition refrigerants?

Short answer? Everyone eventually. But that’s not why you’re reading this I bet. The long answer is a little more complicated - “it depends on where you live, what systems you’re operating, and whether you’re planning to build something new soon.” People will be forced into using transition refrigerants as a result of the banning of HFCs.

Not sure what a transition refrigerant is? In summary, we consider a transition refrigerant a refrigerant with a GWP between an HFC and a natural refrigerant.

The National Picture – A Recent History Lesson


In 2015 and 2016, EPA adopted an extensive set of amendments to its extant SNAP rules of note are SNAP 20 and 21. The SNAP 20 regulations were invalidated by the Circuit Court of Appeals for the District of Columbia, to the extent they replaced allowable HFCs with lower GWP HFCs, as exceeding EPA’s statutory authority. That decision then led to the Court also invalidating SNAP 21 in 2019. By then, the then-new administration had declared it would not enforce the SNAP 20 and 21 rules unless and until it underwent a new rulemaking action to address the court’s decision and rationale and in 2018 EPA stated it will not enforce those rules until further rulemaking is completed. 83 Fed. Reg. 18431 (April 27, 2018). No further action has been taken by EPA to re-adopt these SNAP rules.


On December 27, 2020, the American Innovation and Manufacturing (AIM) Act of 2020 was enacted as section 103 in Division S, Innovation for the Environment, of the Consolidated Appropriations Act, 2021 (H.R. 133 (116th): Consolidated Appropriations Act, 2021 [Including Coronavirus Stimulus & Relief]). The AIM Act directs EPA to address HFCs by providing new authorities in three main areas: to phase down the production and consumption of listed HFCs, manage these HFCs and their substitutes, and facilitate the transition to next-generation technologies.


The AIM Act, which was included in the Consolidated Appropriations Act, 2021, directs EPA to phase down the production and consumption of HFCs in the United States by 85 percent over the next 15 years. A global HFC phasedown is expected to avoid up to 0.5° Celsius of global warming by 2100.

This final rule is the first regulation under the AIM Act to address HFCs, which are potent greenhouse gases commonly used in refrigerators, air conditioners, and other applications. This final rule sets the HFC production and consumption baseline levels from which reductions will be made establish an initial methodology for allocating and trading HFC allowances for 2022 and 2023 and creates a robust, agile, and innovative compliance and enforcement system.

The reach of the AIM act

Yes, that was a lot of citing cases and timelines. So what does that actually mean for you? Over the next 15 years, the AIM Act will phase down the production and consumption of HFCs nationally by 85%. That seems like a long way off, no?

Well, you guessed it, requirements are coming sooner than the 2030s, and individual states are critical to track, because, in lieu of federal guidance, they’re taking more aggressive action. The ringleader? As always, California. To understand how we need to meet our friends SNAP 20 and 21.

What are SNAP rules 20 and 21?

Established under the Clean Air Act, the Environmental Protection Agency’s (EPA) Significant New Alternatives Policy (SNAP) program identifies and evaluates substitutes for ozone-depleting substances by end-use. SNAP Rules 20 and 21 list specific HFC refrigerants as unacceptable and identify acceptable alternatives.

When a state adopts SNAP 20/21, it's adopting this specific list of unacceptable and acceptable refrigerants and typically indicating a timeline and applications when those refrigerants can or can’t be used. In a short blog post, we can’t touch on every scenario, but we can provide the tools to figure it out.

The below chart, a screenshot from NASRC's policy tracker, shows a comprehensive summary of legislative action by each state.

Image courtesy of NASRC HFC Policy Tracker. Visit their site for more detailed summaries of each state.

State-Level Differences of SNAP

Now say we were thinking about building a new supermarket in New Jersey in 2021. New Jersey adopted SNAP 20/21 via Bill A5583 AcaSca (2R) in new supermarket refrigeration systems effective July 1, 2020. As such, we would be required to use refrigerants listed on the SNAP 20/21 approved lists for supermarket refrigeration (found here) in our new store. And guess what? Yes, we’d be required to use transition refrigerants. The same store in Idaho? No such restrictions.

Where do we go from here?

These rules and their implications continue to emerge and create new scenarios. We stay up-to-date on the recommendations so that we can confidently offer you the best value solution.