Believe it or not you can buy propane based universal refrigerants in the good ole USA. Iso-butane is what is in a Bic lighter yes, it is also a greenie-weenie mandated refrigerant for use in appliances now in Europe. So an eco-Nazi appliance blew up in an apartment and set the low bidder non fire retardant eco-Nazi mandated exterior cladding on fire and caused an inferno that so far has claimed 76 lives. All in the name of saving the planet, a win win for mother Gaia. The law of unintended consequences shall not be mocked.