WASHINGTON — The U.S. Environmental Protection Agency (EPA) is warning homeowners, propane manufacturers and sellers, home improvement contractors, and air conditioning technicians of potential safety hazards related to the use of propane or other unapproved refrigerants in home air conditioning systems. The government organization is currently investigating instances where propane has been marketed and used as a substitute for R-22.

According to the EPA, home air conditioning systems are not designed to handle propane or other similar flammable refrigerants. The use of these substances poses a potential fire or explosion hazard for homeowners and service technicians.

The EPA is aware of incidents that have occurred both overseas and in the United States where individuals have been injured as a result of the use of propane and other unapproved refrigerants in air conditioning systems.

“We are investigating and will take enforcement actions where appropriate,” said the EPA. “Other names for these unapproved refrigerants include R-290, 22a, 22-A, R-22a, HC-22a, and CARE 40.”

At this time, EPA has not approved the use of propane refrigerant or other hydrocarbon refrigerants in any type of air conditioner. Homeowners and technicians are strongly recommended to limit use of propane or other hydrocarbons to only those appliances specifically designed for these substances and that are properly marked to alert technicians that the equipment contains a flammable substance. EPA has approved the use of propane as a substitute refrigerant for R-22 in industrial process refrigeration systems and in new, stand-alone retail food refrigerators and freezers that are specifically designed to use flammable hydrocarbon refrigerants.