R-453A

For R-453A, ashrae safety class is A1, verified against its source on 2026-08-11.

Refrigerant: R-453A verified
ASHRAE safety class: A1 verified
Retrofit / new: retrofit per federalregister.gov
Listing status / notes: acceptable, subject to use conditions per federalregister.gov

Verified2026-08-11

Review by2027-08-11

What the source says

ASHRAE 34-2024 categorizes HFO-1234yf and R-444A as being in the A2L Safety Group and R-453A, R-456A, and R-480A in the A1 Safety Group.

— federalregister.gov, retrieved 2026-08-11

List the blend R-453A as acceptable, subject to use conditions, in retrofit MVACs on buses and trains; and

— federalregister.gov, retrieved 2026-08-11

federalregister.govhttps://www.federalregister.gov/documents/2025/11/10/2025-19812/protection-of-stratospheric-ozone-listing-of-substitutes-under-the-significant-new-alternatives

Last verified against source: 2026-08-11. Due for re-check by 2027-08-11. This page as Markdown · OKF bundle · full dataset as JSON.