Application: Detect leaks in air-conditioner and other refrigerant systems. It will respond all halogen gases (including Chlorine and Florine),which include but are not limited to: CFCs : R12, R11, R500, R503, HCFCs : R22, R123, R124, R502, R134a, R404a, R125 Detect Ethylene Oxide gas leaks in hospital sterilizing equipment (it will detect the homogenate carrier gas). Detect SF-6 in high voltage circuit breakers. Detect cleaning agents used in dry cleaning applications such as perchloroethylene.