EPA is highlighting the safety hazards related to using propane in existing motor vehicle and home air conditioning systems. A number of refrigerants with "22a" or "R-22a" in the name contain highly flammable hydrocarbons, such as propane. Using a propane-based refrigerant in an air conditioner that is not designed for flammable refrigerants can cause the system to catch fire or explode, resulting in injury and property damage.
EPA has approved numerous substitute refrigerants that are safer for you and the environment that can be used to retrofit existing systems. Learn more about 22a and alternatives for air conditioning here. http://go.usa.gov/5Vy5
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