What are AC (air conditioning) safety stickers?

Air conditioning systems are under extreme pressure and can cause injury. The details on these safety labels allow qualified personnel to operate on your A/C safely. Details such as the proper refrigerant (R-134a or HFC-134a) or oil (PAG & POE) and whether or not the system contains dye or coolant must be known before working on your Air Conditioner. AC labels are typically found under the hood, if not on the hood, then in the engine bay. AC & coolant labels can also contain warnings about moving parts or hot temperatures you may encounter during maintenance.

What else can my Air Conditioning label tell me?

Your AC & coolant label can also contain safety specifications that are set by SAE International. Your label will indicate SAE J-639 compliance. Also indicated are refrigerant charges and lubricant. The tolerance of the system will be indicated with a + or -, denoting the range the system can safely operate within.

Manufacturers often use the same AC & coolant labels across multiple cars, so be sure you are using the information provided for your vehicle and engine type.