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.

That means the customer has to accept that HFO-1234yf can be deadly under certain circumstances, for instance, one of the four models crash tested by the KBA burst into flames and emitted a considerable amount of toxic hydrogen fluoride.

This is not the kind of news potential customers want to hear, even if they already realize there are other potentially dangerous liquids in every car on the road.

At the same time, the EU has banned R134a from new-model vehicles because it is much worse for the environment than HFO-1234yf.

In France, you can’t take delivery of your new A class or B class or CLA because each still uses R134a.

Does that mean customers who are thinking about purchasing new-model cars with R134a in other markets will face the hassle of a recall? Thoughts like this cause doubt and doubt kills sales.

The industry needs a final ruling on this matter — and it needs it fast.