Germany’s Transport Ministry says the release of the country’s Kraftfahrt-Bundesamt (KBA) road safety authority preliminary report concerning r134yf as an air-conditioning refrigerant is not a victory for any particular party.

Mercedes-Benz, the European Commission (EC) and the French Environment Ministry, are locked in a bitter dispute surrounding the rival claims of the Brussels-mandated r1234yf chemical and the Germans’ preferred r134a variant.

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All sides appear to remain as far apart as ever and have highlighted their particular preferences in the KBA report, but the German Ministry is opting to keep a neutral line.

“It is nothing to do with victory – it is one step on the way to solving the technical problem,” a German Transport Ministry spokeswoman told just-auto from Berlin. “They are sorting out the technical issue.

“They will need some time to do some extra testing. There are still questions relating to that liquid. It is not a political issue, it is a technical issue.

“There is a legal issue to be solved between us, Paris and Brussels where European legislation is being adhered to.”

Mercedes points out the testing is complete, but the report is not, while sticking to its view: “The old refrigerant does not burn – the new refrigerant does – so we have a higher risk with [the] new refrigerant.”

For its part the EC says it “still considers there is no evidence there is a general safety risk related to the flammability of the refrigerant HFO 1234yf,” while chemical provider Honeywell maintains: “”Honeywell continues to stand firmly behind the safety of HFO-1234yf, and it will continue to supply its customers to enable them to comply with the MAC directive.

“With the exception of Daimler, there is broad consensus that HFO-1234yf poses no greater risk than HFC-134a in cars.”

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