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EPA Section 608 · plain answers
EPA 608 leak rate questions, answered
Every answer cited to 40 CFR 82.157, 40 CFR 82.152 or 40 CFR 84.106
The leak rate questions that come up on the job, and the ones that come up in EPA 608 exam prep, with the paragraph of the regulation each answer comes from. If you want the arithmetic done for you, the EPA 608 leak rate calculator is free and does not ask for anything.
Starting in 2019, leaking industrial process refrigeration with an ozone depleting refrigerant must be repaired when the leak rate exceeds what?
30% of the full charge per year. Commercial refrigeration is 20%, and comfort cooling or any other covered appliance is 10%. Those three figures took effect on January 1, 2019 and have not changed since.
40 CFR 82.157(c)(2)
What size appliance does the Section 608 leak repair rule apply to?
A full charge of 50 pounds or more. Since April 10, 2020 the rule reaches only appliances holding 50 pounds or more of a class I or class II refrigerant, or a blend containing one. An appliance charged solely with a substitute refrigerant is not covered by 82.157 at all.
40 CFR 82.157(a)
When must the leak rate of an appliance be calculated?
Every time refrigerant is added. Not annually, not on suspicion of a leak: on every addition. Three additions are excused, and only three: one made immediately following a retrofit, the first charge of a newly installed appliance, and one that qualifies as a seasonal variance.
40 CFR 82.157(b)
How is the leak rate actually calculated?
It is the percentage of the appliance’s full charge that would be lost over 12 months if the current rate of loss carried on, and there are two permitted ways to work it out.
Annualizing method. Divide the pounds added to return the appliance to full charge by the pounds it holds at full charge. Divide the shorter of the days since refrigerant was last added or 365 by 365. Divide the first figure by the second, then multiply by 100.
Rolling average method. Add up the pounds put in over the previous 365 days, or since the last successful follow-up verification test if that is more recent. Divide by the full charge, then multiply by 100.
Whichever you choose, the same method has to be used for every appliance subject to leak repair at an operating facility.
40 CFR 82.152, definition of leak rate
How long do I have to repair the leak?
30 days from the day the refrigerant was added, or 120 days where an industrial process shutdown is required. Inside that window a certified technician has to conduct a leak inspection to find the leaks, the leaks have to be repaired, and an initial verification test has to show the repairs hold.
40 CFR 82.157(d) and (e)(1)
What are the two verification tests?
The initial verification test is done inside the same 30 or 120 day window, after the repair work and before any more refrigerant goes in. The follow-up verification test is done within 10 days of a successful initial test, or within 10 days of the appliance reaching normal operating conditions if it had to be evacuated. Both have to be documented.
40 CFR 82.157(e)
What happens if the repairs do not get the appliance under the threshold?
The owner or operator has to create and implement a retrofit or retirement plan. You cannot simply keep topping the appliance up.
40 CFR 82.157(c)(1), (h) and (i)
How often do leak inspections have to be done after that?
Commercial refrigeration and industrial process refrigeration appliances holding 500 pounds or more go on quarterly inspections until four quarters in a row come in under the threshold. Appliances from 50 to 500 pounds, and comfort cooling or other appliances of 50 pounds or more, are inspected once per calendar year on the same basis.
40 CFR 82.157(g)
When does a leak have to be reported to the EPA?
An appliance holding 50 pounds or more that leaks 125% or more of its full charge in a calendar year has to be reported by March 1 of the following year, along with an account of what was done to find the leaks and repair it.
40 CFR 82.157(j)
How long do the records have to be kept?
Three years, on paper or electronically. The record of the appliance itself, including its full charge and how that charge was determined, has to be kept until three years after the appliance is retired.
40 CFR 82.157(l)
Does purged refrigerant count against the leak rate?
Not if it is destroyed at a verifiable destruction efficiency of 98% or greater. Purged refrigerant that is not destroyed to that standard does count.
40 CFR 82.157(k)
My appliance runs on R-410A. Is it under Section 608?
Not for leak repair. HFCs and other substitutes come under 40 CFR 84.106 instead, which took effect on January 1, 2026 and starts at a full charge of 15 pounds rather than 50. The three thresholds are the same three figures. Residential and light commercial air conditioning and heat pumps are outside it.
40 CFR 84.106(a)
Knowing the rule is the easy part
AirCert keeps the sum, the clock and the record together
A site full of appliances, some under Section 608 and some under the HFC rule, each with its own threshold, its own repair deadline and three years of records to produce on request, is where this gets hard. 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
Section 608 leak repair, thresholds, deadlines, inspections and recordkeeping are at 40 CFR 82.157. The leak rate definition and both formulas are at 40 CFR 82.152. The HFC leak repair rule is at 40 CFR 84.106. The EPA’s own pages are at epa.gov/section608.
This is a guide, not legal advice, and it is not an EPA study course. It reflects the regulations 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.