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Questions and Answers About the Safety Risks of Using Hydrocarbons (HCs) in Motor Vehicle Air Conditioners (MVACs)

1. Is it safe to use hydrocarbon (HC) refrigerants in motor vehicle air conditioners (MVACs)?

No. HC refrigerants, such as propane, are highly flammable and are not acceptable alternatives for MVACs under the Clean Air Act and the EPA’s Significant New Alternatives Policy (SNAP) Program.

2. What are the safety risks of using HCs in MVACs?

The EPA strongly advises against using HC refrigerants in MVACs. The use of these refrigerants in MVACs can result in fire or explosion, possibly causing injury and property damage. It may also void your car’s warranty.

3. Under EPA regulations, can any flammable HC refrigerant or HC refrigerant blends be used in MVACs?

Given concerns for safety, there are no HC refrigerants listed as acceptable by the EPA’s SNAP Program for use in MVACs. All flammable refrigerants, except two non-HC refrigerants: R-152a (also known as HFC-152a) and R-1234yf (HFO-1234yf), are unacceptable for use in new and retrofit MVACs. Importantly, R-152a and R-1234yf are acceptable for new MVACs only, where there are built-in safety features.

4. Are HC refrigerants available for sale on the open market?

While unsafe and not approved under the EPA’s SNAP Program, HC refrigerants for use in MVACs can be purchased online and in stores, often in small cans. These cans can only be sold to certified technicians under CAA Sections 608 or 609, unless the cans have a self-sealing valve. They are sometimes advertised as replacements for refrigerants such as R-134a and R-1234yf. They have been sold under a variety of names, including ZeroR AC Refrigerant and Arctic Air for HFO-1234yf. The advertisements for these products may not mention that the alternative is a HC, such as propane, or a blend of HCs, or clearly state the safety risks associated with use of the product.

5. What should I do if I suspect a HC refrigerant was used in my MVAC?

If you believe that a HC refrigerant was introduced into your MVAC, the EPA recommends that you contact a certified Section 609 technician at an auto repair shop or your state or local fire marshal for guidance. You will want to provide as much information as you can, such as:

  • What HC refrigerant and/or which refrigerant product was charged into your MVAC
  • How much HC refrigerant was added
  • Where the HC refrigerant was purchased
  • When the HC refrigerant was added
  • Why the HC refrigerant was added (e.g., top-off for a leaky system)

Refrigerant recovery equipment that has been designed and approved for use with flammable refrigerants is available and the technician or fire marshal should be able to help you safely remove the HC refrigerant.

6. Which refrigerants are allowed to be used in MVACs?

The list of acceptable refrigerants for use in MVACs is available on the EPA’s SNAP Program website.

7. What should I do if I see small cans of HC refrigerant being sold?

Please contact the EPA by visiting our Contact Us page.