HVAC Compliance Calculator
EPA Refrigerant Leak Rate Calculator
The AIM Act leak repair rule (40 CFR 84.106) took effect January 1, 2026. Enter the charge and the refrigerant you added, and this tool runs the exact EPA formula, checks the 10/20/30 percent thresholds, and lists every deadline you are on the hook for.
Mirroring EPA's own fact sheet language: this information is provided for informational purposes only and should not be relied on for compliance. The regulation of record is 40 CFR part 84, subpart C. For compliance questions EPA lists HFCEmissionsReductions@epa.gov.
Leak Rate Thresholds by Appliance Type
| Appliance type | Threshold | Citation |
|---|---|---|
| Comfort cooling (chillers, splits, RTUs) | 10% | 84.106(c)(2)(iii) |
| Data center / computer room / ITEF cooling (comfort cooling per 89 FR 82700) | 10% | 84.106(c)(2)(iii) |
| Refrigerated transport | 10% | 84.106(c)(2)(iii) |
| Other covered appliances (15+ lb) | 10% | 84.106(c)(2)(iii) |
| Commercial refrigeration (retail food, cold storage) | 20% | 84.106(c)(2)(i) |
| Industrial process refrigeration (IPR) | 30% | 84.106(c)(2)(ii) |
Repairs must be performed by a certified technician (84.106(c)(1)) and only need to bring the leak rate below the applicable threshold (84.106(d)(2)).
AIM Act Deadlines: 84.106 Leak Repair and 84.108 Leak Detection
| Obligation | Deadline | Citation |
|---|---|---|
| Leak inspection and repair | 30 days (120 days if an industrial process shutdown is required) | 84.106(d) |
| Initial verification test | Within the same 30 or 120 day window | 84.106(e)(1) |
| Follow-up verification test | Within 10 days of the successful initial test | 84.106(e)(2) |
| Recurring inspections: commercial refrigeration and IPR, 500+ lb | Quarterly, until no exceedance for four quarters in a row | 84.106(g)(1) |
| Recurring inspections: commercial refrigeration and IPR, 15 to under 500 lb | Once per year, until no exceedance for one year | 84.106(g)(1) |
| Recurring inspections: comfort cooling and other covered appliances | Once per year, until no exceedance for one year | 84.106(g)(1) |
| Retrofit or retirement plan | Create within 30 days; complete within one year of the plan's date | 84.106(h) |
| Chronically leaking appliance report (125%+ of full charge in a calendar year) | By March 1 of the subsequent year | 84.106(j) |
| ALD install: appliance installed on or after Jan 1, 2026 | At installation or within 30 days | 84.108(b) |
| ALD install: appliance installed Jan 1, 2017 through Dec 31, 2025 | By January 1, 2027 | 84.108(b) |
Deadline clocks are suspended while an appliance is mothballed (evacuated to at least atmospheric pressure and temporarily shut down) and resume when refrigerant is added back (84.106(d)(3)).
If your appliance runs only an ozone-depleting refrigerant such as R-22, 84.106(a)(3)(i) excludes it and the Section 608 rule at 40 CFR 82.157 governs instead, but only at a full charge of 50 or more pounds (82.157(a)). Below 50 lb neither rule imposes a leak repair duty. Where 82.157 does apply, the repair, verification and retrofit deadlines above are the same, at 82.157(d), (e) and (h), and the chronic-leak report is still due March 1, though 82.157(j) sets its trigger at 50 lb rather than 15 lb. Three rows do not carry over as printed. Neither automatic leak detection row applies: 82.157 never mandates an ALD, it only lets one substitute for recurring inspections (82.157(g)(4)). The recurring inspection rows move to 82.157(g)(1), where the middle band runs 50 to under 500 lb rather than 15, and inspections are due once per calendar year rather than once per year measured from the successful follow-up verification test.
How the Two Calculation Methods Work
The formulas live in the definition of leak rate at 40 CFR 84.102, not in 84.106 itself. The definition opens with a constraint that trips people up: "The same method must be used for all appliances subject to the leak repair requirements located at an operating facility." Pick one method per facility, not per unit.
Annualizing Method (84.102, Leak rate (1))
The regulation spells it out in four steps, quoted directly:
"Step 1. Take the number of pounds of refrigerant added to the appliance to return it to a full charge, whether in one addition or in multiple additions related to same leak, and divide it by the number of pounds of refrigerant the appliance normally contains at full charge; Step 2. Take the shorter of the number of days that have passed since the last day refrigerant was added or 365 days and divide that number by 365 days; Step 3. Take the number calculated in Step 1 and divide it by the number calculated in Step 2; and Step 4. Multiply the number calculated in Step 3 by 100 to calculate a percentage."
In algebra, that works out to: leak rate = (lb added ÷ full charge) ÷ (min(days since last addition, 365) ÷ 365) × 100. The min(days, 365) cap means a top-off after 500 quiet days is treated as 365 days, never diluted further. For the first calculation after January 1, 2026, substitute 365 days as the number of days since the last addition (84.106(b)(1)).
Rolling Average Method (84.102, Leak rate (2))
Also quoted directly from the regulation:
"Step 1. Take the sum of the pounds of refrigerant added to the appliance over the previous 365-day period (or over the period that has passed since the last successful follow-up verification test showing all identified leaks in the appliance were repaired, if that period is less than one year); Step 2. Divide the result of Step 1 by the pounds of refrigerant the appliance normally contains at full charge; and Step 3. Multiply the result of Step 2 by 100 to obtain a percentage."
For the first use after January 1, 2026, count the pounds of refrigerant added since January 1, 2026 (84.106(b)(2)). A leak rate calculation is required every time refrigerant is added, unless the addition immediately follows a retrofit or a new installation, or qualifies as a seasonal variance (84.106(b)). Purged refrigerant that is destroyed at a verifiable destruction efficiency of 98 percent or greater does not count toward the rate (84.106(k)).
Worked Example: Same Leak, Two Very Different Numbers
A commercial appliance normally holds 100 lb at full charge. You add 15 lb to return it to full charge, 92 days after the last addition.
Annualizing: Step 1: 15 ÷ 100 = 0.15. Step 2: min(92, 365) ÷ 365 = 0.252. Step 3: 0.15 ÷ 0.252 = 0.595. Step 4: 0.595 × 100 = 59.5% per year. That exceeds every threshold in 84.106(c)(2).
Rolling average: if that 15 lb is the only refrigerant added in the trailing 365 days, the rate is 15 ÷ 100 × 100 = 15% per year. Below the 20% commercial refrigeration threshold, above the 10% comfort cooling threshold. Same leak event, and the method choice decides whether a 30-day repair clock starts. The annualizing method reacts fast to a fresh leak; the rolling average smooths it across the year. This example is our own construction to illustrate the formulas; the regulation and EPA's fact sheet do not publish a numeric example.
AIM Act Rule (84.106) vs Section 608 Rule (82.157)
Both leak repair rules are in force at once, split by refrigerant. HFC appliances follow 40 CFR 84.106; ODS appliances (R-22 and other CFC/HCFC systems) follow 40 CFR 82.157, and only at a full charge of 50 lb or more. The 2016 update to Section 608 had extended leak repair to HFC appliances at 50 lb, the 2020 rollback rescinded that, and the AIM Act ER&R rule reinstates HFC coverage at a tighter 15 lb trigger effective January 1, 2026.
| Item | AIM Act rule (40 CFR 84.106) | Section 608 rule (40 CFR 82.157) |
|---|---|---|
| Charge-size trigger | 15 lb full charge | 50 lb full charge |
| Covered refrigerants | Any refrigerant containing an HFC, or a non-HFC substitute with GWP > 53 | Only CFCs and HCFCs (e.g. R-22) or blends containing one, since April 10, 2020 |
| Residential / light commercial AC | Exempt (84.106(a)(3)(ii)) | No exemption; any 50+ lb ODS appliance is covered |
| Leak rate thresholds | 30% IPR / 20% commercial refrigeration / 10% comfort cooling, refrigerated transport, other | Identical 30/20/10 (82.157(c)(2)); refrigerated transport not named |
| Repair deadline | 30 days (120 with industrial process shutdown) | Same |
| Verification tests | Initial within 30/120 days, follow-up within 10 days | Same |
| Automatic leak detection | Mandatory for IPR and commercial refrigeration at 1,500+ lb | Never mandatory; optional substitute for inspections |
| Effective date | January 1, 2026 | January 1, 2019 (ODS-only scope since April 10, 2020) |
Which Refrigerants Are Covered
The applicability test in 40 CFR 84.106(a) has a nuance that catches even experienced techs. The GWP-greater-than-53 test applies only to substitutes, and EPA defines a substitute as a substance that itself contains no HFC and no ODS (84.102). Any refrigerant containing any HFC at all is covered under 84.106(a)(1) no matter how low the blend GWP is. R-454B (GWP 465 per EPA's Technology Transitions reference table) is covered because it contains HFC-32. So are R-454C (GWP 146) and R-513A (GWP 630). The GWP escape hatch only exists for non-HFC refrigerants: HFOs like R-1234yf, hydrocarbons like R-290, CO2, and ammonia, all with GWPs at or below 53 per Table 1 to 40 CFR 84.64(b).
Two chiller refrigerants get opposite answers under the same test. R-515B (R-1234ze(E)/227ea): Contains HFC-227ea (8.9 percent by mass, ASHRAE 34), a regulated substance, so it is covered under 84.106(a)(1). Its GWP of 287 is irrelevant to coverage; the 53 cutoff applies only to refrigerants with no HFC in them. R-1233zd(E) (HCFO): Non-HFC substitute with GWP 4 in Table 1 to 84.64(b), the table 84.106(a)(2) names, at or below the 53 cutoff, not covered. EPA's SNAP chiller listing prints a range of 4.7 to 7 for the same fluid; the verdict is the same at any value in it. Not a class I or class II ozone-depleting substance under 40 CFR part 82 subpart A, so 82.157 does not reach it either.
Data center, computer room and ITEF cooling gets a different answer under each EPA program, and EPA said so in the rule itself (89 FR 82700). For leak repair it is comfort cooling at 10 percent. Under Technology Transitions it is its own subsector: new systems installed on or after January 1, 2027 may not use an HFC or HFC blend with a GWP of 700 or greater (40 CFR 84.54(c)(13)), and increasing the cooling capacity of an existing system counts as an installation (84.54(e)(2)). The calculator asks which program you mean before it classes the equipment.
For a regulated substance (the HFCs) the GWP values the rule uses are the AIM Act exchange values in Appendix A to part 84, which are numerically identical to the IPCC AR4 100-year GWPs; for a non-HFC substitute, 84.106(a)(2) names Table 1 to 84.64(b) instead. Blend GWPs are the mass-weighted sum of the constituents per 40 CFR 84.64(b). The lowest exchange value assigned to any regulated substance is 53 (HFC-152), which is where the cutoff comes from. HFC-152a (GWP 124) is itself a regulated substance, so it is covered despite the low number.
Frequently Asked Questions
Is a data center chiller comfort cooling or industrial process refrigeration?
It depends on which EPA program you are asking about, and EPA says so itself. For the ER&R leak repair rule, EPA answered in the final rule's response to comments (89 FR 82700) that appliances cooling data centers, ITEF, computer rooms and communications rooms "are considered comfort cooling for purposes of the ER&R program", so the leak-rate trigger is 10 percent under 40 CFR 84.106(c)(2)(iii), not the 30 percent IPR trigger, recurring inspections after an exceedance are annual, and there is no automatic leak detection mandate at any charge size. A chiller serving both a process load and a data center is industrial process refrigeration if 50 percent or more of its operating capacity serves the process (84.102). Under Technology Transitions the same equipment is its own subsector: new systems installed on or after January 1, 2027 may not use an HFC or HFC blend with a GWP of 700 or greater (40 CFR 84.54(c)(13)). Pick the program first; this calculator asks that question before it asks what the equipment is.
What is an acceptable or allowable refrigerant leak rate?
The rule does not set an acceptable rate; it sets the rate above which repair becomes mandatory. For an appliance with a full charge of 15 pounds or more of a covered refrigerant, that trigger is 10 percent per year for comfort cooling (including data center and computer room cooling), refrigerated transport and other covered appliances, 20 percent for commercial refrigeration, and 30 percent for industrial process refrigeration (40 CFR 84.106(c)(2)). Below the trigger no repair duty arises under the rule, but the leak rate must still be calculated on every addition, except one made immediately after a retrofit or a new installation or one that qualifies as a seasonal variance (84.106(b)), and kept on record. Residential and light commercial AC and heat pumps are outside 84.106 entirely (84.106(a)(3)(ii)).
How do I determine the leak rate, and can I do it in a spreadsheet?
Yes, and the formula is short enough to check by hand. Annualizing method: pounds added divided by full charge, divided by (the shorter of days since the last addition or 365, divided by 365), times 100. Rolling average method: pounds added over the trailing 365 days, or since the last successful follow-up verification test if that is less than a year, divided by full charge, times 100. Both are defined in 40 CFR 84.102 and this calculator prints every intermediate step so a spreadsheet can be checked against it. What a spreadsheet will not do on its own is decide coverage (15 lb, HFC content or GWP above 53, the subsector exclusion), pick the right threshold for the subsector, or start the 30 day repair clock and the verification-test deadlines, which is the part that goes wrong.
Is R-515B covered by the leak repair rule? Is R-1233zd(E)?
R-515B is covered: contains HFC-227ea (8.9 percent by mass, ASHRAE 34), a regulated substance, so it is covered under 84.106(a)(1). Its GWP of 287 is irrelevant to coverage; the 53 cutoff applies only to refrigerants with no HFC in them. R-1233zd(E) is the opposite case and is not covered: non-HFC substitute with GWP 4 in Table 1 to 84.64(b), the table 84.106(a)(2) names, at or below the 53 cutoff, not covered. EPA's SNAP chiller listing prints a range of 4.7 to 7 for the same fluid; the verdict is the same at any value in it. Not a class I or class II ozone-depleting substance under 40 CFR part 82 subpart A, so 82.157 does not reach it either. Both answers come from the same test in 84.106(a): any regulated-substance (HFC) content means covered, and the 53 GWP cutoff is only applied when there is no HFC at all.
Which appliances are covered by the EPA leak repair rule?
40 CFR 84.106 applies to refrigerant-containing appliances with a full charge of 15 or more pounds where the refrigerant contains a regulated substance (any HFC) or a non-HFC substitute with a GWP greater than 53. That pulls in R-410A, R-404A, R-134a, R-32, R-454B, R-448A, R-449A, R-513A, and every other HFC-containing blend. Appliances running solely an ozone-depleting substance like R-22 are excluded by 84.106(a)(3)(i) and fall under the Section 608 rule at 40 CFR 82.157, which reaches them only at a full charge of 50 or more pounds (82.157(a)); below 50 lb neither rule imposes a leak repair duty. For devices with multiple circuits, each independent circuit counts as a separate appliance for the 15 lb test (84.102).
Is residential air conditioning exempt?
Yes. Appliances in the residential and light commercial air conditioning and heat pump subsector are excluded by 40 CFR 84.106(a)(3)(ii), even when they hold 15 or more pounds of a covered refrigerant. The exemption does not extend to chillers or certain VRF systems, which EPA treats as their own subsectors. Residential techs should still track leaks: this calculator shows the rate as an informational number for exempt equipment.
What is the 125 percent chronically leaking appliance rule?
Under 40 CFR 84.106(j), an appliance with a full charge of 15 or more pounds that leaks 125 percent or more of its full charge in a calendar year must be reported to EPA by March 1 of the subsequent year. The report (contents listed in 84.106(m)(4)) includes the appliance and refrigerant type, full charge, annual percent loss, dates and amounts of additions, the cause, repairs taken, any retrofit or retirement plan, and a signed statement from a company official.
When is automatic leak detection (ALD) required?
40 CFR 84.108(a) requires ALD systems on industrial process refrigeration and commercial refrigeration appliances with a full charge of 1,500 pounds or more of a covered refrigerant. Comfort cooling appliances are never required to install ALD regardless of size. Appliances installed on or after January 1, 2026 need ALD at installation or within 30 days; appliances installed on or after January 1, 2017 and before January 1, 2026 need it by January 1, 2027. The rule sets no ALD deadline for appliances installed before January 1, 2017.
How long do leak rate records have to be kept?
At least three years, in electronic or paper format, per 40 CFR 84.106(l). Per-service records must include the amount and type of refrigerant added, the full charge, and the leak rate with the method used to determine it (84.106(l)(2)). Full-charge records are the exception: those must be kept until three years after the appliance is retired (84.106(l)(1)). Technicians must hand service documentation to the owner or operator at the conclusion of service.
What counts as a seasonal variance?
A seasonal variance is refrigerant removed because of a seasonal change in ambient conditions, followed by re-addition of no more than the amount removed, with both steps inside one consecutive 12-month period (40 CFR 84.102). Additions that qualify as a seasonal variance do not trigger a leak rate calculation (84.106(b)), but usage must be recorded (84.106(l)(12)).
Does purged refrigerant count toward the leak rate?
Not if it is destroyed. Under 40 CFR 84.106(k), purged refrigerant that is destroyed at a verifiable destruction efficiency of 98 percent or greater is not counted toward the annual leak rate. Supporting records (flow rate, refrigerant concentration in the vent stream, control device description and destruction efficiency) must be kept per 84.106(l)(11). The Section 608 rule carries the identical carve-out for ozone-depleting refrigerants at 40 CFR 82.157(k), with the supporting records at 82.157(l)(9), which is the paragraph an R-123 low-pressure chiller runs under. A purge that vents to atmosphere rather than to a destruction device gets no carve-out under either rule.
What if the repair cannot be finished in 30 days?
The base deadline is 30 days from the refrigerant addition, or 120 days if an industrial process shutdown is required (40 CFR 84.106(d)). Extensions are available under 84.106(f) for radiological contamination, conflicting federal, state, local, or Tribal regulations, or unavailable components: up to 30 days after part delivery, capped at 180 days (270 with an industrial process shutdown) from the exceedance. The request must be filed electronically with EPA within the initial window. The clock also pauses while an appliance is mothballed, meaning evacuated to at least atmospheric pressure and temporarily shut down (84.106(d)(3)).
Which method should I use, annualizing or rolling average?
Either, but the same method must be used for all appliances subject to the leak repair requirements at an operating facility (40 CFR 84.102). The annualizing method projects the most recent addition to a 12-month rate, so it reacts fast to a fresh leak. The rolling average method sums everything added over the trailing 365 days. Switching methods is only allowed after acquiring a facility that used a different method, and only if no appliance whose method would change is exceeding its threshold under either method, with a record kept of the change (84.106(b)(3)).
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