The US Environment Protection Agency (EPA) announced that the refrigerant HFO-1234yf has been approved for use in car air-conditioning systems. The approval was granted despite open questions regarding the substance's impact on health and the environment that have led several organisations to openly advice against its use.

“The US administration has approved a substance whose evolution is not fully foreseeable yet. HFO-1234yf can be the next environmental time bomb: HCFC destroyed the ozone layer and HFCs are climate warming gases. Each time, chemical substances were praised to be the solution for all problems, only to reveal their nasty surprises in the short run", says Christianna Papazahariou, head of the campaign BeyondHFCs.

1234yf raises these concerns when used in cars' climate control systems:

- flammability: 1234yf is a flammable refrigerant;

- toxicity: results by the German Federal Institute for Materials Research show that 1234yf forms highly toxic hydrogen fluoride at concentrations dangerous to human life when burning or in contact with hot surfaces;

- environmental impact: the decomposition products include trifluoroacetic acid (TFA) which can lead to water toxicity;

 

Further concerns about HFO-1234yf have to do with ozone depletion, a higher than expected global warming potential, ozone production at ground level as well as purity and the need for new PAG oils in A/C units.

"The fact that EPA has approved a flammable refrigerant for automotive air-conditioning raises another question: why not use hydrocarbons, if flammability is not an issue any more?" asks BeyondHFCs. Hydrocarbons are natural refrigerants that are flammable but have been used safely in the automotive service market for decades. They have the great advantage to be a drop-in solution for R134a, the standard refrigerant in mobile air-conditioning. 

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