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Resources for Stationary Refrigeration and Air-Conditioning Equipment Technicians

The following information can help technicians and contractors who service stationary refrigeration and air-conditioning equipment, as well as their customers.

Section 608 Technician Certification

Technicians must pass an EPA-approved test given by an EPA-approved certifying organization in order to become certified. Additional information about the Section 608 Technician Certification.

Phaseout of Ozone-Depleting Substances (ODS)

Learn about the phaseout of ODSHelpODSA family of man-made compounds that includes, but are not limited to, chlorofluorocarbons (CFCs), bromofluorocarbons (halons), methyl chloroform, carbon tetrachloride, methyl bromide, and hydrochlorofluorocarbons (HCFCs). These compounds have been shown to deplete stratospheric ozone, and therefore are typically referred to as ODSs. See ozone., and how the phaseout affects technicians and contractors.

Questions and Answers for Technicians

Read common questions and answers for technicians

Alternative Refrigerants

Learn what ODS alternatives are acceptable for use in stationary refrigeration and air conditioners.

Flammable Refrigerants and Technician Safety

Refrigerants with “22a” or “R-22a” in their names are highly flammable substances that are not approved for use in existing air-conditioning systems. These refrigerants have never been submitted to EPA for review of their health and environmental impacts. Using these propane-based refrigerants in an air conditioner that is not designed for flammable refrigerants poses a threat to homeowners and service technicians. EPA is investigating instances where propane-based refrigerants have been marketed and used as a substitutes for hydrochlorofluorocarbonHelphydrochlorofluorocarbonA compound consisting of hydrogen, chlorine, fluorine, and carbon. The HCFCs are one class of chemicals being used to replace the CFCs. They contain chlorine and thus deplete stratospheric ozone, but to a much lesser extent than CFCs. HCFCs have ozone depletion potentials (ODPs) ranging from 0.01 to 0.1. Production of HCFCs with the highest ODPs are being phased out first, followed by other HCFCs. A table of ozone-depleting substances ( shows their ODPs, GWPs, and CAS numbers. HCFCs are numbered according to a standard scheme ( (HCFC)-22 (also called R-22) and has taken enforcement actions where appropriate.

Access more information about R-22a and alternatives for air conditioning.

Reporting Violations of the Section 608 Regulations

Access information on how to report a violation of the Section 608 regulations.

Learn about EPA’s efforts to enforce regulations to protect the ozone layerHelpozone layerThe region of the stratosphere containing the bulk of atmospheric ozone. The ozone layer lies approximately 15-40 kilometers (10-25 miles) above the Earth's surface, in the stratosphere. Depletion of this layer by ozone depleting substances (ODS) will lead to higher UVB levels, which in turn will cause increased skin cancers and cataracts and potential damage to some marine organisms, plants, and plastics. The science page ( offers much more detail on the science of ozone depletion..

Materials to Share with Customers

EPA has developed several fact sheets and other outreach materials for owners of stationary refrigeration and air conditioning equipment. Technicians can use these materials as handouts for engaging with their customers.

Additional Information

Access links to stationary refrigeration and air-conditioning technician trade groups.