EPA Proposes New Refrigerant Approval for Heavy-Duty Truck Air Conditioning
Published Date: 4/6/2026
Proposed Rule
Summary
The EPA wants to officially approve a new refrigerant called HFO-1234yf for use in heavy-duty pickup trucks and vans’ air conditioning systems, but with some rules to keep things safe. This update adds details and invites the public to share their thoughts by May 6, 2026. If you’re in the vehicle or refrigeration world, this could affect your choices and costs soon!
Analyzed Economic Effects
2 provisions identified: 2 benefits, 0 costs, 0 mixed.
New Refrigerant Allowed for Heavy-Duty Retrofits
The EPA proposes to list the refrigerant HFO-1234yf (CAS Reg. No. 754-12-1) as “acceptable, subject to use conditions” for retrofitting motor vehicle air conditioning (MVAC) systems in heavy‑duty (HD) pickup trucks and complete HD vans. This would give vehicle makers, repair shops, and others another refrigerant option for retrofits and increase flexibility for industry; the EPA requested public comment on the supplemental proposal with comments due on or before May 6, 2026.
EPA Safety Finding for HFO-1234yf Use
The EPA's risk screen found that HFO-1234yf is not expected to cause a significant risk to human health in the general population when manufactured for use and used as a refrigerant in HD pickup truck and complete HD van AC systems, provided systems are installed with proper engineering controls and follow manufacturer guidance. The EPA noted HFO-1234yf’s 8‑hour occupational exposure limit (OEL) of 500 ppm and concluded use in this end‑use can be managed to stay at or below that level.
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Key Dates
Department and Agencies
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