The Clean Air Act prohibits the knowing release of ozone- depleting and substitute refrigerants during the course of maintaining, servicing, repairing, or disposing of appliances or industrial process refrigeration. The existing regulations require that persons maintaining, servicing, repairing, or disposing of air-conditioning and refrigeration equipment containing more than 50 pounds of refrigerant observe certain service practices that reduce emissions of ozone- depleting refrigerant. This rule updates those existing requirements as well as extends them, as appropriate, to non-ozone depleting substitute refrigerants, such as hydrofluorocarbons. Updates include strengthened leak repair requirements, recordkeeping requirements for the disposal of appliances containing more than five and less than 50 pounds of refrigerant, revisions to the technician certification program, and revisions for improved readability and compliance. As a result, this action reduces emissions of ozone-depleting substances and gases with high global warming potentials.