After receiving input from industry, environmental groups, and others, EPA is increasing available options for refrigerants, which offer improved climate protection without harming ozone layer, for use in refrigeration and air conditioning equipment in U.S. Approved substitutes have global warming potential (GWP) ratings from 3–675 and can replace older compounds with GWP from 1,400–4,000. All climate-friendly alternatives, except HFC-32, are exempt from Clean Air Act venting prohibition.