HVAC Systems · Refrigeration — Refrigerants & ASHRAE 34
ASHRAE Standard 34
The standard that assigns refrigerants their "R-" number and a two-character safety group based on toxicity and flammability. It is the source of designations like R-410A and classes like A1 or A2L.
Common uses
Identifying and comparing refrigerants; required by ASHRAE 15 and building codes
Related terms
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