How is the annualized leak rate calculated?

EPA Section 608 annualizes leaks: leak rate equals refrigerant added divided by full charge, times 365 divided by the days since the last addition, expressed as a percent. This extrapolates a partial-year top-up to a full-year rate.

What are the EPA Section 608 leak-rate thresholds?

For appliances with at least 50 pounds of charge, the repair triggers are 10 percent per year for comfort cooling, 20 percent for commercial refrigeration and 30 percent for industrial process refrigeration. Exceeding the threshold requires repair within 30 days.

What is global warming potential (GWP)?

GWP is how much heat a gas traps relative to carbon dioxide over 100 years. R-410A has a GWP near 2088, so one pound of it leaked is roughly equivalent to 2088 pounds of CO2, which is why high-GWP refrigerants are being phased down.

What is the AIM Act HFC phasedown?

The American Innovation and Manufacturing Act directs the EPA to cut production and import of high-GWP hydrofluorocarbons over time. Chronic leakers on refrigerants like R-404A and R-410A are strong candidates to retrofit to lower-GWP blends such as R-32 or R-454B.

Does the rule apply to small systems?

The Section 608 leak-rate repair mandate applies to appliances containing 50 pounds or more of refrigerant. Smaller systems fall outside the formal trigger, though prompt leak repair remains good practice and venting is always prohibited.

What is the Refrigerant GWP & EPA Section 608 Quantity Calculator?

Compute the annualized leak rate from refrigerant added versus full charge, compare against EPA Section 608 thresholds (10 percent comfort, 20 percent commercial, 30 percent industrial), and report the charge CO2-equivalent from bundled refrigerant GWP values for AIM Act compliance. It runs free in your browser on Gera Tools, with nothing uploaded.

Refrigerant GWP & EPA Section 608 Quantity Calculator

Name: Refrigerant GWP & EPA Section 608 Quantity Calculator
Creator: Gera Tools
License: https://creativecommons.org/licenses/by/4.0/

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Refrigerant leaks are both a cost and a compliance issue. Under EPA Section 608, commercial systems that leak above a threshold must be repaired within 30 days, and high-GWP refrigerants face phasedown under the AIM Act. This calculator annualizes your leak rate, checks it against the regulatory trigger, and reports the climate impact of the full charge.

How it works

EPA annualizes leaks from the refrigerant added since the last service:

leak_rate% = (added / full_charge) × (365 / days_since_add) × 100

That rate is compared to the threshold for the appliance type: 10 percent comfort cooling, 20 percent commercial refrigeration, 30 percent industrial process refrigeration, for systems holding at least 50 lb. The charge’s climate impact is its CO2-equivalent:

CO2e (lb) = charge_lb × GWP

Worked example

A comfort-cooling system with a 100 lb charge of R-410A receives 8 lb of top-up 90 days after its last service:

leak_rate = (8 / 100) × (365 / 90) × 100 = 8 × 4.056 ≈ 32.4%

That far exceeds the 10 percent comfort-cooling threshold, so a repair is required within 30 days. The full charge represents 100 × 2088 = 208,800 lb of CO2-equivalent, approximately 95 metric tons.

Common refrigerant GWP values

The GWP figures below are the 100-year values used by EPA for Section 608 compliance reporting:

Refrigerant	Type	GWP (100-year)
R-22	HCFC (phased out)	~1,810
R-404A	HFC blend	~3,922
R-410A	HFC blend	~2,088
R-407C	HFC blend	~1,774
R-134a	HFC	~1,430
R-32	HFC (lower-GWP)	~675
R-454B (Opteon XL41)	HFO/HFC blend	~466
R-290 (propane)	HC (A3 flammability)	~3
R-744 (CO2)	Natural	1

R-404A is particularly scrutinized under the AIM Act due to its very high GWP and widespread use in commercial refrigeration.

AIM Act context

The American Innovation and Manufacturing Act of 2020 gives EPA authority to phase down HFC production and import in the US, broadly following the Kigali Amendment to the Montreal Protocol. The phasedown reduces HFC consumption in stages — this tightens supply and raises prices for high-GWP refrigerants like R-410A and R-404A over time.

Systems that are chronic leakers on these refrigerants face growing operating cost from increasingly expensive refrigerant plus Section 608 compliance exposure. Retrofitting to a lower-GWP blend (R-32, R-454B, or R-32-based blends for air conditioning; R-448A or R-449A for commercial refrigeration) is often the more cost-effective long-term path compared with repeated recharging.

Tips and notes

The annualizing method means a small top-up over a short interval can imply a high annual rate — this is intentional, since it flags fast leaks early before a full year elapses. Track each refrigerant addition with its date so the day count is accurate. Venting refrigerant is always prohibited regardless of charge size. For systems that repeatedly trigger the threshold, a leak search and repair followed by a retrofit evaluation is the right sequence.