Final answer:
EPA regulations cover equipment containing ozone-depleting substances such as CFCs and HCFCs in air conditioning and refrigeration, with laws mandating alternatives like HFCs.
Step-by-step explanation:
The equipment covered by EPA regulations include all air conditioning and refrigeration equipment containing and using ozone-depleting substances, primarily Chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), and other compounds that harm the ozone layer.
These substances were once commonly used in refrigeration and aerosol sprays due to their stability and low toxicity, but it was discovered that they deplete the ozone layer, which protects Earth from harmful ultraviolet radiation.
Laws have mandated the use of alternative refrigerants such as hydrofluorocarbons (HFCs), which do not deplete the ozone layer.
The Clean Air Act was amended in 1990 to accelerate the phaseout of CFCs and HCFCs, enforce regulations on the handling and disposal of refrigerants, and promote the development and adoption of alternative technologies.