[jabl]

Here in Europe (and I believe in many other parts of the world as well) propane and butane have been the standard refrigerant in domestic appliances for a couple of decades. I think the industry went straight to these when CFC's were banned.

Considering that your average refrigerator contains a quite modest amount of refrigerant, compared to all the other flammable stuff in your average apartment, it's not really any significant fire risk.