Okay to recharge a car AC with R134a, but not Okay with R12 for

Is it legal to recharge your car’s air conditioning at home? The answer is yes, with a few exceptions. Do not add Freon to automobiles made prior to 1993 or to one that uses R-12 for refrigerant. This is illegal and can only be done by a certified mechanic. A good rule of thumb that I checked on by asking a few of the local parts stores was, if the part store sells recharge kits or Freon in the store to the general public than it should be legal to use those supplies to recharge your own air-conditioning system.