On April 19, 2023, EPA finalized Rule 25 – Protection of Stratospheric Ozone: Listing of Substitutes under the Significant New Alternatives Policy Program in the Refrigeration & Air Conditioning and Fire Suppression Sectors. In this rule, EPA lists seven refrigerants and three fire suppressants as “acceptable, subject to use conditions” or “acceptable, subject to narrowed use limits.” The rule also adopts recent air conditioning and refrigeration industry standards to ensure the safe use of covered refrigerants. SNAP Rule 25 affects chemical producers, equipment manufacturers, commercial and consumer end users of equipment and products using refrigerants and fire suppressants, and service technicians.

The refrigerants listed as acceptable are:

• HFO-1234yf
• R-454A
• R-454B
• R-454C
• HFC-32
• R-452B
• R-1150 (ethylene)

The fire suppression substitutes listed as acceptable are:

• 2-BTP
• EXXFIRE®
• Powdered Aerosol H (Pyroquench-α™)

Note that, while allowed, each substitute has conditions and narrow use limits.

Following the December 2020 American Innovation and Manufacturing (AIM) Act, these new HFC alternative listings support the transition in the U.S. from hydrofluorocarbons (HFCs) to alternatives with lower global warming potential (GWP).   

SNAP Rule 25 follows other recent rulemakings on the HFC front, and will give way to more rules addressing HFCs and alternatives in the future as EPA continues to regulate under its new AIM Act authority.