Remember the hazy, lazy days of summer. Lying on the beach, cooling off in the water. Then walking back to the car, opening the door and being hit with the wall of super heated air. First thing is to start the car and put the air conditioning on full force.
If you have an older car, the refrigerant used is likely freon or R-12. However, R-12, is partially responsible for depletion of the ozone layer. The refrigerant is no longer manufactured and its use is strictly controlled. If you have a failure with your air conditioning system, you will likely require a conversion kit to modify the type of coolant used to a much less harmful R-134a. These conversions are reliable, and let you do your part to protect the environment.