EPA Section 608 of the Clean Air Act and the AIM Act Part III (40 CFR Part 84 Subpart C, effective January 2026) impose federal compliance obligations on every HVAC technician and building operator who handles or owns systems containing regulated refrigerant. The threshold was lowered from 50 pounds to 15 pounds as of 2026, bringing the majority of commercial rooftop units, split systems, and chiller plants into full recordkeeping scope. Leak repair obligations apply to ozone-depleting refrigerants; the AIM Act is extending equivalent requirements to high-GWP HFCs. Violations carry civil penalties up to $44,539 per day per violation. Records must be retained for three years and be available for EPA inspection on demand. OxMaint’s compliance tracking and predictive monitoring platform calculates annual leak rates automatically on every refrigerant addition, schedules the required inspection and verification events, and stores every record per asset ID in an EPA-audit-ready format — eliminating the spreadsheet gaps that expose facilities during inspections.
01 — Leak Rate Thresholds: When Repair Obligations Are Triggered
EPA requires the leak rate to be recalculated every time refrigerant is added to a system containing 50 or more pounds of regulated refrigerant (15 or more pounds under AIM Act Part III). If the calculated rate exceeds the applicable threshold, a repair obligation begins — and the 30-day clock starts from the date the leak was discovered (typically the service date of the refrigerant addition). Leak rate must be recalculated using the annualising or rolling average method, both of which produce an annualised percentage.
Equipment Category
Leak Rate Trigger
Inspection Frequency (Post-Trigger)
Automatic Detection Required
Repair Deadline
Comfort Cooling (HVAC)
10% annualised leak rate
Annual inspection until rate < 10% for 1 year
1,500 lb+ charge (AIM Act 2026–2027)
30 days from discovery
Commercial Refrigeration
20% annualised leak rate
Quarterly (>500 lb charge); annual (50–500 lb)
1,500 lb+ charge (AIM Act 2026–2027)
30 days from discovery
Industrial Process Refrigeration (IPR)
30% annualised leak rate
Quarterly (>500 lb charge); annual (50–500 lb)
1,500 lb+ charge (AIM Act 2026–2027)
30 days (120 days with EPA extension)
Chronic Leaker (all types)
125%+ of full charge in 12 months
Report to EPA by March 1 of following year
—
EPA notification mandatory
Leak Rate Calculation Methods — EPA Section 608
Annualising Method
Leak Rate = (lbs added ÷ full charge lbs) × (365 ÷ days since last addition) × 100%
Days in denominator = shorter of: days since last addition, or days since installation if no prior addition exists.
Rolling Average Method
Leak Rate = (total lbs added in past 365 days ÷ full charge lbs) × 100%
Requires cumulative refrigerant addition log for 12 months. More accurate for systems with multiple small additions throughout the year.
02 — Refrigerant Leak Detection Checklist
A leak inspection is the systematic examination of an appliance to identify the location of refrigerant leaks before or after the threshold is exceeded. EPA Section 608 and AIM Act Part III require documentation of the inspection date, method used, locations of identified leaks, and a certification that no leaks were discovered (or all identified leaks were repaired). Technicians performing inspections on systems with 50 or more pounds must be Section 608 certified.
Pre-Inspection: System Documentation Verification
Confirm system asset record is current: refrigerant type, full charge (lbs), installation date, and any charge changes documented with date and methodRecord: Asset register · Ref: 40 CFR 82.166(a), AIM Act Part III
Calculate current annualised leak rate (annualising or rolling average method) before opening system — determine if threshold is already exceededRecord: Leak rate calculation with method noted · Ref: 40 CFR 82.157(b)
Confirm Section 608 certification of all technicians performing leak inspection — record certification type and number on service reportRecord: Technician cert number on invoice · Ref: 40 CFR 82.161
Select and confirm calibration status of leak detection equipment — electronic leak detectors, ultrasonic devices, or gas-imaging cameras must be maintained per manufacturer guidelinesRecord: Detection method and equipment calibration date · Ref: 40 CFR 82.157(c)
Inspection: Systematic Leak Location
Inspect all mechanical connections: flare fittings, brazed joints, compression fittings — these are the most common leak points in commercial HVAC systemsRecord: Location of each point inspected, result (pass/leak found)
Inspect all service valves (Schrader valves, ball valves) for core seal condition and cap presence — missing or loose valve caps are a common source of chronic low-level leakageRecord: Valve condition at each inspection point
Inspect evaporator and condenser coils — check for oil staining (indicative of refrigerant and oil co-migration through a leak) and physical coil damageRecord: Coil condition; oil stain location photographed where found
Inspect compressor shaft seal (where applicable) and crankcase pressure — shaft seals are a primary leak point on reciprocating and scroll compressorsRecord: Compressor seal inspection result
For systems with ≥1,500 lbs of HFC refrigerant: confirm automatic leak detection (ALD) system is installed, operational, and calibrated within the past 12 months per AIM Act 2026Record: ALD calibration date · Ref: AIM Act Part III · Required: Jan 2027 for existing systems
Post-Inspection: Documentation
Document inspection date, method used, list of all points inspected, location of any leaks identified, and result (no leaks found / leaks found at [locations])Record: Inspection report to customer · Ref: 40 CFR 82.166(c)(10)
If leaks found: initiate repair work order immediately. Record discovery date as the start of the 30-day repair clock. Notify building owner/operator of obligation and repair timelineRecord: Repair WO raised with discovery date · Ref: 40 CFR 82.156(a)
03 — Repair & Verification Checklist
After a leak is repaired, EPA requires two verification tests: an initial verification test (conducted before refrigerant is returned to the system) and, if the initial test passes, a follow-up verification test conducted within 30 days. Both must be documented with location of the repaired leak, test method, test date, and result. A failed follow-up test requires the owner/operator to either repair and retest, or notify EPA within 30 days and retrofit or retire the equipment.
Repair: Before Returning System to Service
Recover all refrigerant from the affected section per Section 608 recovery requirements before opening the system for repair — certified recovery equipment required, evacuation level must meet 40 CFR 82.156(f)Record: Recovery date, cylinder ID, lbs recovered · Ref: 40 CFR 82.156(f)
Complete all identified repairs — document repair method (re-braze, replace fitting, replace valve core, coil section repair) and location for each repaired pointRecord: Repair description per location · Ref: 40 CFR 82.157(d)
Pressure test repaired section with dry nitrogen to 1.1× MAWP before recharging — hold for minimum 15 minutes and confirm no pressure drop indicating a remaining leakRecord: Pressure test pressure, duration, result
Initial Verification Test
Conduct initial verification test before adding refrigerant: pressurise system with nitrogen or trace amount of refrigerant and perform leak test at all repaired locations using electronic detector or equivalent methodRecord: Date, test method, each location tested, result (pass/fail) · Ref: 40 CFR 82.157(d)
If initial verification test passes: record pass result, add refrigerant, return system to service. If fails: complete additional repairs and retest before adding refrigerantRecord: Pass/fail result and subsequent action · Ref: 40 CFR 82.157(d)(1)
Log refrigerant amount added (lbs), type, and date — invoice to customer must show quantity and type of refrigerant added. Update running annual total for this applianceRecord: Invoice + asset charge log updated · Ref: 40 CFR 82.166(a)
Recalculate annualised leak rate after refrigerant addition — confirm system is now below applicable threshold (10% comfort cooling / 20% commercial / 30% IPR). If still above threshold: re-enter repair cycleRecord: Updated leak rate calculation with method · Ref: 40 CFR 82.157(b)
Follow-Up Verification Test (within 30 days of initial repair)
Return to the appliance within 30 days of the initial repair — conduct follow-up verification test at all originally identified leak locations while system is operating at normal operating pressureRecord: Follow-up test date, method, all locations tested · Ref: 40 CFR 82.157(d)(2)
If follow-up test passes: document pass result. Repair cycle is complete. Record must show dates of initial repair, initial verification, and follow-up verification for each repaired locationRecord: Follow-up pass result · Ref: 40 CFR 82.157(d)(2)
If follow-up test fails: owner/operator must notify EPA within 30 days and either: (a) repair and retest within 180 days, or (b) retrofit to approved alternative refrigerant, or (c) retire the applianceRecord: EPA notification date and action taken · Ref: 40 CFR 82.156(d)–(e)
Calculate Leak Rates Automatically. Schedule Verification Tests. Never Miss a 30-Day Deadline.
OxMaint calculates your annualised leak rate on every refrigerant addition, auto-schedules the follow-up verification test, and stores every Section 608 record per asset — so your compliance documentation is always current and always ready for EPA audit.
04 — Records and Reporting: What EPA Requires You to Keep
Section 608 requires owners and operators of appliances with 50 or more pounds (15 lbs under AIM Act 2026) to maintain records accessible for a minimum of three years. Technicians are required to provide invoices documenting refrigerant additions. Both must be available for EPA inspection on demand — and “available” means immediately, not after a records search exercise.
Per Appliance Record (Owner/Operator)
Location of appliance within site and site address
Owner and operator name and contact information
Full charge of the appliance (lbs) — documented method and date
Any changes to full charge value with date and method
Date and type of service for each service event
Amount and type of refrigerant added at each service
Leak rate calculation results with method used
Date, type, and result of all verification tests
Date of recovery, type and quantity recovered (5+ lb systems)
Per Service Invoice (Technician)
Amount and type of refrigerant added (required on every invoice)
Technician Section 608 certification type and number
Date of inspection and method(s) used
Location of each leak identified during inspection
Certification that no leaks found (where applicable)
Dates and results of all initial and follow-up verification tests
Location of each repaired leak that was verification tested
Annual EPA Reporting (Chronic Leakers)
Submit to EPA by March 1 if any appliance leaked ≥125% of full charge in prior calendar year
Report includes appliance location, refrigerant type, full charge, and total refrigerant added
Include status of repair, retrofit, or retirement of the chronic leaker
Extension requests must be filed within 30 days of failed follow-up verification test
Retain all supporting records for minimum 3 years after appliance retirement
Frequently Asked Questions
Does the EPA Section 608 10% leak rate threshold apply to R-410A systems in 2026?
The traditional Section 608 leak repair obligations apply only to ozone-depleting refrigerants (R-22 and other ODSs). However, the AIM Act Part III (40 CFR Part 84 Subpart C), effective January 2026, extends equivalent leak rate requirements to appliances containing HFCs with a GWP above 53, including R-410A, R-404A, and R-134a. The threshold under AIM Act Part III mirrors Section 608 by equipment category. Facilities should verify their specific compliance status with current regulations and their EPA regional office, as AIM Act implementation timelines continue to evolve. OxMaint configures the applicable threshold per asset and automatically flags when a leak rate calculation exceeds the threshold for that refrigerant type. Start your free trial to configure leak rate thresholds per system in your portfolio.
What happens if a building cannot complete the repair within 30 days?
EPA Section 608 provides a 120-day extension (from the date of discovery) for industrial process refrigeration equipment where a repair requires custom fabricated parts or extensive system isolation that cannot be completed in 30 days. Comfort cooling and commercial refrigeration equipment does not have this extended deadline — the 30-day limit applies. If the 30-day window cannot be met for comfort cooling or commercial refrigeration, the owner/operator must notify EPA and commit to a retrofit or retirement timeline. All extension requests and notifications must be documented and retained in the appliance record. Book a demo to see how OxMaint tracks the 30-day repair deadline per asset and escalates approaching deadlines automatically.
Is a follow-up verification test always required, or only when the initial test fails?
A follow-up verification test is required whenever a repair is made to an appliance that contains 50 or more pounds of regulated ozone-depleting refrigerant and that system had exceeded the applicable leak rate threshold. The follow-up test must be conducted within 30 days of the initial repair, regardless of whether the initial verification test passed. The purpose is to confirm the repair holds under operating conditions and pressure rather than just under static test conditions. Both tests — initial and follow-up — must be documented with date, method, locations tested, and result, and both records must be provided to the appliance owner on the service invoice.
Can OxMaint automatically flag when a system becomes a chronic leaker?
Yes. OxMaint calculates the rolling 12-month refrigerant addition total for each asset and flags the system when cumulative additions reach or exceed 125% of the full charge — the EPA chronic leaker threshold requiring annual EPA reporting by March 1. The platform also calculates the annualised leak rate on every refrigerant addition entry and compares it against the configured threshold for that equipment category. When a threshold is exceeded, OxMaint generates a work order for the required inspection or repair event and starts the compliance deadline clock. All calculation records, work order history, and verification test results are stored per asset ID and exportable in EPA audit-ready format.
Stop Managing Section 608 Compliance in Spreadsheets. Start Tracking It per Asset.
OxMaint calculates leak rates automatically, schedules inspections and verification tests, tracks the 30-day repair deadline per system, and archives every Section 608 and AIM Act record in an EPA audit-ready format across your HVAC portfolio.
