The Refrigerant Compliance Glossary

The site whose appliances are grouped for compliance — the unit at which a leak-rate calculation method must be applied consistently and at which registration and reporting are typically assessed.

A factory-charged, hermetically sealed unit containing 5 pounds or less of refrigerant — household refrigerators, window units, water coolers. Not subject to leak repair requirements.

A closed refrigerant loop that can be isolated and charged independently of others in the same physical unit. Each independent circuit is treated as its own appliance for compliance purposes.

Any device containing and using a refrigerant for cooling, heating, or dehumidifying. Each independent refrigerant circuit in a multi-circuit system counts as a separate appliance.

The charge size at which AIM Act Subpart C obligations attach. Appliances holding 15 pounds or more of an HFC — or of a substitute with a GWP above 53 — became subject to leak repair, leak inspection, recordkeeping, and reporting on January 1, 2026. Residential and light commercial AC and heat pumps are exempt. Section 608’s comparable threshold, for

Refrigeration units on trailers, containers, and rail cars. Called out explicitly under AIM Act Subpart C with a 10% leak-rate threshold.

Complex, customized refrigeration serving an industrial process — chemical and pharmaceutical manufacturing, ice rinks, and power generation. If 50% or more of an appliance’s capacity serves an industrial process, it is classified as IPR, with a 30% federal threshold and a 120-day repair window when shutdown is required.

Retail food and cold storage refrigeration — supermarkets, convenience stores, restaurants, and warehouses. Federal leak-rate threshold is 20%.

Air conditioning for occupied spaces — chillers, split systems, and packaged rooftop units serving human comfort rather than a product or process. Carries the strictest federal leak-rate threshold at 10%.

The application category that sets an appliance’s leak-rate threshold — comfort cooling, commercial refrigeration, industrial process refrigeration, or other. Classification follows what the equipment does, not what it looks like.