The EPA 15-lb Threshold: What Changed on January 1, 2026

Under the old rule (pre-2026), only systems containing 50 lbs or more of refrigerant were subject to EPA leak rate tracking requirements under 40 CFR Part 82, Subpart F. On January 1, 2026, the AIM Act rule (40 CFR Part 84, Subpart C) dropped the threshold to 15 lbs. Covered systems with a full charge of 15 lbs or more must now comply with leak rate tracking, mandatory repair timelines, and chronic leaker reporting. Two exemptions are written into the rule (84.106(a)(3)): appliances containing only ozone-depleting refrigerants (those stay under the old Part 82 rules), and appliances in the residential and light commercial air conditioning and heat pump subsector — a typical home split system or heat pump is NOT federally required to be tracked under Subpart C, even at 15 lbs or more.

The biggest impact falls on covered equipment that was previously below the 50-lb threshold but sits at or above 15 lbs. That means refrigeration equipment above all: reach-in coolers and display cases in convenience stores and restaurants, walk-in coolers and freezers in small commercial kitchens, and small refrigeration racks. It also pulls in commercial comfort cooling outside the exempt residential/light-commercial AC and heat pump subsector — think larger commercial split systems, packaged rooftop units serving bigger buildings, and small chillers — plus transport refrigeration at 15 lbs or more. What it does NOT pull in: residential split systems, residential heat pumps, and light commercial AC/HP equipment, which 84.106(a)(3)(ii) exempts from Subpart C regardless of charge. Systems below 15 lbs remain exempt too, though EPA venting prohibitions still apply to all systems regardless of charge size.

For every system with ≥15 lbs of refrigerant, equipment owners must track all refrigerant additions with dates and quantities, calculate leak rates using an EPA-approved method (Annualizing or Rolling Average), initiate repairs within 30 days if the calculated leak rate exceeds the category threshold (10% for comfort cooling, 20% for commercial refrigeration, 30% for industrial process), conduct verification testing after repairs, report chronic leakers (systems exceeding 125% of full charge in additions per calendar year) to the EPA by March 1 of the following year, and maintain records for a minimum of 3 years for audit purposes.

The threshold reduction is part of the AIM Act's broader strategy to reduce HFC emissions. By bringing smaller systems under regulatory oversight, the EPA expects to identify and repair leaks that have been going undetected for years. The agency estimates that the 15-lb threshold will prevent millions of pounds of additional refrigerant emissions annually — a significant contribution to climate goals under the Kigali Amendment.

Start by inventorying every system you own or service. Identify which systems have a full charge of 15 lbs or more and are not in the exempt residential/light-commercial AC and heat pump subsector — these are now in scope. For each regulated system, you need to know the full charge in lbs, the equipment category (comfort cooling, commercial refrigeration, industrial process, or transport), the refrigerant type, and the serial number and location. Next, choose your calculation method — Annualizing or Rolling Average — and apply it consistently across your organization. Finally, set up a tracking system that can calculate leak rates automatically, flag threshold exceedances, track repair deadlines, and generate audit-ready reports.