Refrigerant R134a
International Fire Code section 606.16 – “ELECTRICAL EQUIPMENT. Where refrigerants of Groups A2, A3, B2 and B3 as defined in the International Mechanical Code, are used, refrigeration machinery rooms shall conform to the Class I, Division 2 hazardous location classification requirements of the ICC Electrical Code”
Refrigerant, R134a, is classified as Group A1.