R-134a is a non-ozone depleting, hydrofluorocarbon (HFC) refrigerant. It was originally designed as a replacement refrigerant for R-12, an ozone depleting, chlorofluorocarbon (CFC). R-134a is the standard in many mobile air conditioning (AC) units.

R-134a can be used in many applications that previously use dichlorodifluoromethane (R-12). These include refrigeration, polymer foam blowing, and aerosol products. The thermodynamic and physical properties of R-134a, coupled with its low toxicity, make it a very efficient and safe replacement refrigerant for CFC-12 in many segments of the refrigeration industry, most notably in automotive air conditioning, appliances, small stationary equipment, medium-temperature supermarket cases, and industrial and commercial chillers.