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EPA compliance · free tool
Refrigerant leak rate calculator
Built to 40 CFR 84.102 and 84.106 · the AIM Act rule in force since January 1, 2026
Put in the full charge and the refrigerant you added. This works out the leak rate by whichever of the EPA’s two methods you use, tells you the threshold for your appliance, and shows the arithmetic so you can put it in the record.
Calculation method
Capped at 365. Calculating for the first time since January 1, 2026? Use 365.
Calculated leak rate
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Fill in the full charge and the pounds added.
Nothing you type here is sent anywhere or stored. The sum happens in your browser.
How the leak rate is worked out
The EPA defines the leak rate as the percentage of an appliance’s full charge that would be lost over 12 months if the current rate of loss carried on. There are two permitted ways to arrive at it, and they are written into the rule at 40 CFR 84.102.
Annualizing method
Use this when you want the leak rate for the addition in front of you. It takes what you just put in and scales it up to a full year.
- Divide the pounds added to bring the appliance back to full charge by the pounds it holds at full charge.
- Take the shorter of the days since refrigerant was last added or 365 days, and divide that by 365.
- Divide the first number by the second.
- Multiply by 100.
Multiple additions made to chase the same leak count as one addition in step 1. If this is your first annualizing calculation since January 1, 2026, the rule tells you to substitute 365 as the number of days. — 40 CFR 84.102, 40 CFR 84.106(b)(1)
Rolling average method
Use this when you want the appliance’s behaviour over the year rather than one top-up.
- Add up the pounds put into the appliance over the previous 365 days — or, if it is shorter, the period since the last successful follow-up verification test that showed every identified leak repaired.
- Divide by the full charge.
- Multiply by 100.
First rolling average calculation since January 1, 2026? Count only the pounds added since that date. — 40 CFR 84.106(b)(2)
Pick one method and stay with it
This is the part that catches people out. The rule says the same method must be used for every appliance subject to the leak repair requirements at an operating facility. You do not get to run annualizing on the chiller and rolling average on the rack because it flatters the number.
You can only switch methods in one narrow situation: you have bought or otherwise acquired a facility that was using the other method, and you can show its appliances are not over the threshold under either method. You then have to keep a record of the change.
Which threshold applies
| Appliance type | Leak rate threshold |
|---|---|
| Industrial process refrigeration (IPR) | 30% |
| Commercial refrigeration | 20% |
| Comfort cooling, refrigerated transport, or anything else not covered above | 10% |
These apply to appliances with a full charge of 15 pounds or more containing an HFC, or a substitute for one with a global warming potential above 53. Residential and light commercial air conditioning and heat pumps are exempt, and appliances running solely on an ozone-depleting refrigerant stay under the older Section 608 rules instead. Which threshold applies to my appliance works through the edge cases.
When must the leak rate of an appliance be calculated?
Every single time refrigerant is added to a covered appliance. Not annually, not when it looks bad — every addition. There are three exceptions: an addition made immediately after a retrofit, the first charge of a newly installed appliance, and an addition that qualifies as a seasonal variance.
If you are over the threshold
The clock starts on the day the refrigerant was added. You have 30 days to find and repair the leaks — 120 if an industrial process shutdown is needed — and both an initial and a follow-up verification test have to be done and documented. The 30-day repair clock and the two verification tests sets out exactly what has to happen and by when.
Straight to your refrigerant
Same calculator, already set to the appliance type that refrigerant is usually found in, plus what it is made of and whether the exemptions reach it.
Doing this on every appliance
AirCert keeps the sum, the clock and the record together
One calculation on one appliance is easy. A site full of them, each with its own threshold, its own repair deadline and three years of records to produce on request, is not. AirCert does the leak rate on every refrigerant addition, starts the repair clock on the right date, schedules both verification tests and prints the record. It is out now on Android, and coming soon to iPhone and iPad.
Get it on Google PlayWhere this comes from
The leak rate definition and both formulas are at 40 CFR 84.102. The thresholds, the repair deadlines and the calculation trigger are at 40 CFR 84.106. The EPA’s own summary is in its January 2026 leak repair fact sheet.
This is a guide, not legal advice. It reflects the rule as published and we have cited every figure, but your obligations depend on your appliances and your circumstances. Check the regulation itself, and take advice if anything about your situation is unusual.