Which Appliances Are Covered
Since 10 April 2020, 40 CFR 82.157 applies only to appliances with a full charge of 50 lb or more of a class I or class II refrigerant (a CFC or HCFC, or a blend containing one). Appliances using only substitutes such as HFCs are not covered by 82.157. HFC leak repair is now handled by separate AIM Act rules in 40 CFR Part 84. ESCO has said those AIM Act requirements will not be on the 608 exam (ACHR News, Sep 2026).
Leak-Rate Triggers
| Appliance type | Repair when annual leak rate exceeds |
|---|---|
| Commercial refrigeration | 20% |
| Industrial process refrigeration | 30% |
| Comfort cooling and other appliances (50 lb or more) | 10% |
The owner or operator must calculate the leak rate every time refrigerant is added, except right after a retrofit, a new installation or a seasonal variance (82.157(b)).
Deadlines and Verification
- Find and repair leaks within 30 days of the refrigerant addition that showed the trigger was exceeded. Industrial process shutdowns get 120 days.
- Do an initial verification test after the repair, then a follow-up verification test once the system is back at normal operating conditions.
- If repair isn't possible, the owner may create a retrofit or retirement plan within 30 days and complete it within one year, with limited extensions.
Leak Inspections After an Exceedance
Commercial and industrial process refrigeration with 500 lb or more must be inspected quarterly until it stays under the trigger for four quarters in a row. Systems of 50–499 lb, and comfort cooling, must be inspected yearly until they stay under the trigger for one year. An automatic leak-detection system audited or calibrated each year can replace these inspections.
Chronic Leakers and Records
Appliances that leak 125% or more of their full charge in a calendar year must be reported to EPA by 1 March of the next year. Records under 82.157 are generally kept for three years.
Practise It
How to Calculate a Leak Rate
The regulation gives two methods for calculating the annual leak rate. Under the annualising method, you divide the pounds of refrigerant added by the full charge, then scale that to a year based on the time since the last addition. Under the rolling average method, you add up all the refrigerant added in the last 365 days (or since the last successful follow-up verification test, if that is shorter) and divide by the full charge. Owners must use the same method for all their appliances subject to the rule.
For example, if a comfort cooling system with a full charge of 100 lb of R-22 needs 15 lb added, the leak rate is at least 15%, which is above the 10% trigger. The owner must then repair the leak within 30 days.
Determining the Full Charge
The full charge is the amount of refrigerant needed for normal operation. The regulation allows several ways to determine it: the manufacturer's information, a calculation based on component sizes and operating conditions, or measurement during installation. A range may be used where conditions vary.
Verification Tests
An initial verification test confirms that the repair worked before the system is returned to service or soon after. A follow-up verification test, done once the system has returned to normal operating conditions, confirms that the repair has held. If either test fails, the owner must repair again or begin a retrofit or retirement plan.
Recordkeeping Responsibilities
Owners and operators keep records of the full charge, each refrigerant addition and the leak rate calculation, leak inspections and verification test results. Technicians must give owners documentation of the service performed, including the amount of refrigerant added. These records help EPA see whether an appliance has a recurring problem.
Why HFC Systems Are Treated Differently
Since 2020, 82.157 has applied only to appliances containing ozone-depleting refrigerants. Leak management for HFC appliances is handled under separate AIM Act rules in 40 CFR Part 84. Those rules are not part of the Section 608 exam, according to the certifying program cited in our sources, but they matter on the job. If you work on larger HFC systems, read the Part 84 rules as well.
Exam Tips
- The rules apply to appliances with 50 lb or more of a CFC or HCFC.
- Triggers: 10% comfort cooling, 20% commercial refrigeration, 30% industrial process refrigeration.
- Repairs are due within 30 days, or 120 days for some industrial process shutdowns.
- Chronic leakers lose 125% or more of their full charge in a year and must be reported.
Worked Example: Commercial Refrigeration
A supermarket rack system holds 600 lb of an HCFC blend. During a service call, the technician adds 60 lb. Using the rolling average method with no other additions in the past year, the leak rate is 60 ÷ 600 = 10%, which is under the 20% commercial refrigeration trigger, so the repair requirement isn't triggered by this addition. If a further 70 lb is added two months later, the rolling total is 130 lb, or about 22%, which is over the trigger. The owner must now repair the leak within 30 days, run the verification tests and, because the system holds 500 lb or more, arrange quarterly leak inspections until it stays under the trigger for four quarters in a row.
What Technicians Should Tell Owners
Technicians are often the first to notice a pattern of refrigerant additions. Give the owner clear documentation of how much refrigerant you added and the date, and explain if the addition may have pushed the system over a trigger. That gives the owner time to meet the 30-day deadline.
Seasonal Variances
Some systems need more refrigerant in cold weather and less in warm weather. The regulation lets owners avoid counting refrigerant added to account for a seasonal variance, provided it is removed later and the records support it.
Key Terms
- Full charge: the amount of refrigerant needed for an appliance to operate normally.
- Leak rate: the rate at which an appliance is losing refrigerant, expressed as a percentage of the full charge per year.
- Initial verification test: a test right after the repair to confirm it worked.
- Follow-up verification test: a later test, at normal operating conditions, to confirm the repair held.
- Retrofit: converting an appliance to a different refrigerant.
- Retirement: taking the appliance out of service permanently.
- Chronically leaking appliance: one that leaks 125% or more of its full charge in a calendar year.
Common Exam Traps
- Applying the 10% trigger to commercial refrigeration. Its trigger is 20%.
- Applying 82.157 to a small residential split system. It only covers appliances with 50 lb or more of a CFC or HCFC.
- Forgetting the follow-up verification test.
- Confusing the 30-day repair deadline with the one-year retrofit or retirement deadline.
Quick Questions
Do I need to calculate the leak rate for a 20 lb R-22 system?
No. The 82.157 leak repair requirements apply only to appliances with a full charge of 50 lb or more of a CFC or HCFC. Smaller systems should still be repaired properly, and venting is never allowed.
Who is responsible for meeting the deadlines?
The owner or operator of the appliance. Technicians support them by documenting refrigerant added and repairs made.
Can an owner avoid repairing by retiring the system?
Yes. An owner can choose a retrofit or retirement plan instead of repair, but the plan must be written within 30 days and completed within one year, with limited extensions.
Are leak inspections the same as verification tests?
No. Verification tests check a specific repair. Leak inspections are periodic checks of the whole appliance required after a trigger is exceeded.
Leak-rate questions show up in the EPA 608 Type III practice test. To check your overall readiness, take the EPA 608 Universal practice test.