Late last year concerns over the harmful effects of a new type of refrigerant, R1234yf, used in car air conditioners and shown by Mercedes-Benz to be flammable in certain situations, such as in a head-on collision, emerged.

This led to the German automaker recalling a number of cars, including the SL-Class here in the U.S., and reverting to the previous R134a refrigerant that R1234yf was meant to replace. R134a was deemed to be harmful to the environment and is currently being phased out of the industry, which is why R1234yf was developed.

Some countries, such as France, have already blocked the sale of new cars fitted with R134a due to concerns of greenhouse gases. Many of these are Mercedes models as other automakers have switched to R1234yf.  

The makers of R1234yf, Honeywell and Dupont, claim its product is safe and is alleged to have accused Mercedes of rigging its test in favor of R134a due to the substantially lower cost of the older refrigerant. R1234yf costs roughly ten times as much as R134a.

More than a dozen other automakers are in the process of testing the safety of R1234yf, some of which, such as General Motors Company [NYSE:GM], have deemed it safe. Others, such as Volkswagen, have sided with Mercedes and plan to develop their own refrigerant.

Unfortunately, while further results on the safety of R1234yf are still to be compiled, the EU is pushing ahead with its mandate to make it standard on all new cars.

According to Reuters, the EU said this week that some Mercedes models were being sold in breach of EU rules, which mandate the use of R1234yf, and according to its preliminary assessment the French ban could be justified. Furthermore, officials from many of the EU countries said all cars should have to meet the rules.

Germany has permitted automakers to use R134a and has since been asked by the EU to explain its decision. The German government has until August 20 to come up with an explanation.

The talks are ongoing but for now it looks like certain Mercedes models will be ban from sale in France and a ban in more countries may follow.

Stay tuned for an update.


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