SAE Panel Says It’s Official: New Refrigerant Is Safe

A group convened by SAE International late last year has declared the automotive refrigerant R-1234yf "safety and effective." The group also dismissed tests to the contrary by Daimler AG as "unrealistic," Inappropriate" and "artificial."

Last September Daimler said its tests showed the new material could catch fire and form poisonous fumes in a crash. The company and the German government petitioned for a delay in the European Union's rule that effectively mandated the use of R-1234yf in new vehicles beginning Jan. 1, 2013.

Daimler said it would continue to use R-134a, the previous industry standard refrigerant, pending further research. The EU threatened to bar the sale of noncompliant vehicles throughout the region and impose sanctions on Germany if it failed to enforce the regulation.

The SAE team used a fault tree analysis to assess the safety of the new refrigerant. Its conclusion, which will be formally published in June, says the risk of passengers being exposed to an R-1234yf fire is "exceptionally remote."

The team also notes that Daimler's testing didn't include actual vehicle collisions and ignored such mitigating factors as refrigerant dispersion or the extinguishing effect of engine coolant steam released during a crash.

R-1234yf has been repeatedly deemed safe in three years of tests by SAE, carmakers and independent labs. The material, which was co-developed by DuPont and Honeywell, has a global warming potential rating of 4 compared with 1,430 for R-134a.