R134a

R134a, also known as 1,1,1,2-tetrafluoroethane, is a hydrofluorocarbon refrigerant used in air conditioning and refrigeration systems. Its chemical formula is CH2FCF3. It is a colorless, non-flammable gas at room temperature and is used in closed-cycle vapor-compression systems. R134a has an ozone depletion potential of zero and a relatively long atmospheric lifetime; its global warming potential (GWP) is about 1430 over a 100-year horizon. The boiling point is about -26 °C at 1 atm.

History and applications: Developed as a replacement for CFC-12 (R-12) in the 1990s, R134a became common in automotive air conditioning and in domestic and commercial refrigeration equipment. It was favored for its non-ozone-depleting properties, but its high GWP has drawn regulatory attention and spurred the search for lower-GWP alternatives.

Regulatory status: Under the Kigali Amendment to the Montreal Protocol, many countries are phasing down HFCs like R134a and moving toward lower-GWP substitutes. For mobile air conditioning, alternatives such as R1234yf are increasingly used, while stationary equipment uses a variety of low-GWP blends or natural refrigerants.

Safety and handling: R134a has low acute toxicity in typical occupational exposure ranges. It is non-flammable but can act as an asphyxiant in poorly ventilated areas if released in large quantities. Servicing should involve recovery and recycling of refrigerant, and venting to the atmosphere should be minimized in accordance with applicable regulations.