The EPA offers four types of certification for refrigerant technicians. The four certifications are for small appliances, low-pressure appliances, high-pressure appliances and a universal certification covering all three types of appliances. This certification scheme was introduced as part of the Clean Air Act introduced into law by the U.S. Congress.
All technicians must have knowledge of the issues surrounding the type of HVAC appliance they are certified in. For example, small-appliance certification requires knowledge of recovery techniques including refrigerant 134 as a substitute. Core knowledge surrounding the use of CFC's and HCFC's, and the Clean Air Act and Montreal Protocol are required for certification in any of the four types of HVAC maintenance and repair.
Certification courses and tests are administered over a two-day period, with five hours of classroom study and a two-hour proctored test. Certification courses offered by Alabama Power cost $150, as of January 2011, with study materials included.