Car research group SAE International says that additional risk analysis after Daimler’s criticism of refrigerant shows chance of fire ‘well below other risks accepted by general public’
SAE said its Co-operative Research Program, compiled with input from Daimler examined two new ‘fault tree scenarios’ to realistically address the carmaker’s claims. The new CRP also reviewed and analysed extensive new OEM test data which was used to complete the new Fault Tree Analysis.
The two new fault tree scenarios consider the possibility of an individual being unable to exit the vehicle due to a collision, or a non-collision event that involves a refrigerant/oil release, the refrigerant/oil being ignited and the fire propagating. SAE said the FTA examined average risks across the entire global fleet and used a number of conservative assumptions to ensure that the final risk estimate would be more likely to overestimate rather than underestimate actual risks.
Based on the updated analysis, SAE said the estimated overall risk of vehicle fire exposure attributed to use of R-1234yf is nearly six orders of magnitude less than the current risk of vehicle fires due to all causes and also well below other risks accepted by the general public.
All OEMs in the new CRP have indicated agreement with these conclusions, it said. The members of the CRP were Chrysler/Fiat, Ford, General Motors, Honda, Hyundai, Jaguar Land Rover, Mazda, PSA, Renault and Toyota.