WARRENDALE, Pa., Feb. 11, 2013 – The SAE International Cooperative Research Project (CRP1234-4) team, which formed last year, met face-to-face during the week of February 4th, 2013. As the CRP continues to review relevant research and testing to finalize the risk assessment, the high level of confidence that R1234yf can be used safely in automotive applications continues to grow. The findings of the original CRP1234 remain well founded in that R1234yf poses no greater risk than other engine compartment fluids.
The CRP continues its process of carefully reviewing the use of R1234yf by using universally accepted engineering methods, including analysis of recent OEM testing from actual vehicle crash data, on-vehicle simulations, laboratory simulations, bench tests, and over 100 engine compartment refrigerant releases. Based on this testing the CRP has found that the refrigerant is highly unlikely to ignite and that ignition requires extremely idealized conditions.
The SAE CRP team of OEMs has also identified that the refrigerant release testing completed by Daimler was unrealistic by creating the extremely idealized conditions for ignition while ignoring actual real world collision scenarios. These conditions include specific combinations of temperature, amount and distribution of refrigerant, along with velocity, turbulence, and atomization, which are highly improbable to simultaneously occur in real-world collisions.
The CRP continues to populate the fault trees to insure completeness of the risk assessment through pragmatic and factual input based on the latest and most accurate data available. Fault tree analysis as conducted by the CRP is the most appropriate approach for evaluating risks of new alternative refrigerants. This approach has been recommended and employed by numerous public and private organizations including the U.S. Environmental Protection Agency, the U.S. Department of Energy, the International Electrotechnical Commission, the European Union Joint Research Centre and the United Kingdom Health and Safety Executive.
The CRP notes with disappointment the recent decision by Daimler to discontinue its participation in the group. This was followed shortly thereafter by BMW and Audi also leaving the CRP. The new CRP began by conducting a detailed review of the original Fault Tree Analysis (FTA). Primarily in response to Daimler’s concerns, the original FTA was significantly expanded to encompass new parameters and incorporate their recent test results. The FTA process is enhanced by having contributions from multiple parties representing a diversity of experience and expertise, building toward consensus under the spirit of collaboration.
The SAE International CRP1234-4 team formed last year to perform an updated engineering review of R-1234yf refrigerant and continues to meet regularly to review and share test information completed since the close of the original CRP1234-3 in 2009. The original CRP1234-3 concluded that R-1234yf is a safe and acceptable alternative refrigerant for mobile air conditioning systems that can be used to meet new environmental standards and consumer needs. The CRP is targeting the second quarter of 2013 for the completion of its work and the publication of a final report.
The SAE CRP1234-4 team includes European, North American and Asian OEMs including Chrysler/Fiat, Ford, General Motors, Honda, Hyundai, Jaguar Land Rover, Mazda, PSA, Renault and Toyota.
SAE International Cooperative Research Programs (CRP) provide neutral environments for joint venture projects where numerous organizations pool their resources and expertise to study areas of common technical interest where results are shared. The information contained in press releases from SAE International CRPs reflects the collective opinion of the partner organizations of the CRP teams.