It is a common name for (HCFC) hydro-chlorofluorocarbon

The R-22 is a commonly used refrigerant used by many HVAC manufactures. It has been in use for over 40 years. However, there is research that shows R-22 contains chlorine, which is an ozone-depleting agent. As such, the U.S. Clean Air Act decreed that as from 1st January 2010, HVAC manufactures should stop production of all products that use HCFC.