The failure of the German Federal Motor Transport Authority (KBA) to make a definitive ruling on the safety of the air conditioning refrigerant HFO-1234yf is bad news for the industry because it gives European car buyers another reason to delay their purchases — just as sales are starting to rebound.

The report says HFO-1234yf is more dangerous than the refrigerant it is supposed to replace, R134a, but the substance is not dangerous enough to pull from the market.