EPA Section 608 Certification Study Guide 2026

How Section 608 certification works

Section 608 of the Clean Air Act and EPA's rules in 40 CFR Part 82, Subpart F require certification for technicians who maintain, service, repair or dispose of equipment that could release refrigerant into the air. A technician is anyone whose work could reasonably be expected to open the refrigerant circuit, for example by attaching hoses or adding or removing refrigerant.

• You must pass a test from an EPA-approved certifying organization. EPA keeps the list of approved programs. Some offer remote or online testing.
• EPA does not issue cards. The certifying organization that tested you issues your card and can replace a lost one.
• Certification does not expire. EPA keeps the right to add recertification in the future.
• Keep a copy of your certificate at your place of business until three years after you stop working as a technician.
• Apprentices may work without certification only while closely and continually supervised by a certified technician.

The test format and pass marks

EPA keeps a bank of questions in groups: a core group and technical groups for each type. Certifying programs build each test from randomly chosen questions.

• Type II, Type III and Universal tests are closed-book and proctored in a secure setting.
• Programs that offer only Type I may use an on-site format or a mail-in format.
• Universal needs a proctored core test. Open-book core tests and mail-in Type I tests cannot count toward Universal.
• You may take Universal all at once, or combine passing scores on separate Type I, II and III tests.
• Proctors check photo ID, such as a driver's license or passport.
• The federal rules do not set a time limit. Ask your certifying organization about its own rules.

Core: ozone, refrigerants and the phaseout

The ozone layer is in the stratosphere, the layer above the one where our weather happens. It absorbs most of the sun's UVB radiation. More UV reaching the ground is linked to skin cancer, cataracts and harm to crops and sea life.

When strong UV light breaks down CFCs and HCFCs high in the atmosphere, they release chlorine. One chlorine atom can destroy over 100,000 ozone molecules.

• The Montreal Protocol is the international treaty to phase out ozone-depleting substances.
• Virgin R-22 has not been allowed in systems made on or after January 1, 2010.
• R-22 was phased out in the United States on January 1, 2020. Existing systems may still be serviced, and recovered or reclaimed R-22 is legal to use.
• There are no true drop-in replacements. Check that oils are compatible when changing refrigerants.

Core: venting, sales and the three Rs

The venting ban

No one servicing or disposing of an appliance may knowingly vent refrigerant. Small releases are de minimis (not a violation) only when they happen while you follow the required practices, such as recovery with certified equipment. Carbon dioxide, nitrogen and water are exempt substitutes and may be released.

Recover, recycle, reclaim

• If recovered refrigerant changes owner, it must be reclaimed by an EPA-certified reclaimer.
• Recovered refrigerant may go back into the same appliance, or another appliance of the same owner.
• Do not mix different refrigerants in one recovery cylinder. A mixture is hard to reclaim.

The sales restriction

• Only certified technicians, or employers who give written proof that they employ one, may buy refrigerant in cylinders, cans or drums for stationary equipment.
• Small cans of MVAC refrigerant (2 pounds or less) with unique fittings and self-sealing valves may be sold to anyone.
• Wholesalers keep invoices with the buyer's name, the date and the quantity.

Core: recovery equipment, evacuation and safety

• Recovery and recycling equipment must be certified by an EPA-approved testing organization (with an exception for some equipment made before November 15, 1993).
• Before opening an appliance, evacuate it to the required level and verify the level.
• A dehydration evacuation at the end of a job removes air and moisture.
• Changing oil above 5 psig is a violation.
• Use dry nitrogen to pressurize for leak checks.
• Refrigerant exposed to flame or very hot surfaces can break down into toxic products.
• Wear eye and hand protection when handling refrigerant and cylinders, and follow labeling rules when shipping cylinders.

When you dispose of an appliance holding more than 5 and less than 50 pounds of refrigerant, keep records for three years: the location, recovery date, refrigerant type, amounts and any transfers for reclaim or destruction.

Type I: small appliances

A small appliance is fully made, charged and hermetically sealed in a factory with 5 pounds or less of refrigerant. Examples are household refrigerators and freezers, window air conditioners and dehumidifiers.

• System-dependent recovery equipment uses the appliance's own parts, such as its compressor, to remove refrigerant. Self-contained equipment does the work on its own.
• For disposal, the final person in the disposal chain (such as a scrap recycler or landfill) must make sure refrigerant was recovered.
• If an appliance arrives empty, the final person keeps a signed statement with the name and address of who recovered the refrigerant and the date. A sticker is not enough.
• People recovering refrigerant from small appliances for disposal do not have to be certified technicians.

Type II: high-pressure appliances

Appliances are classed by the refrigerant's saturation pressure at 104 degrees F.

Required evacuation levels (inches of Hg vacuum)

• Major repair means removing the compressor, condenser, evaporator or auxiliary heat exchanger coil.
• For a non-major repair, bring the appliance to no higher than 0 psig before opening.
• System-dependent recovery may not be used on appliances over 15 pounds, unless it is a permanently attached pump-out unit.

Leak repair rules (Type II and Type III)

The Section 608 leak repair rules in 40 CFR 82.157 apply to appliances with a full charge of 50 pounds or more of ozone-depleting refrigerant (CFC or HCFC).

• Repair leaks within 30 days (120 days if an industrial process shutdown is needed).
• Do an initial and a follow-up verification test. The follow-up is due within 10 days of a successful initial test.
• Commercial and industrial systems of 500 pounds or more need quarterly leak inspections until four quarters in a row are below the trigger rate. Smaller systems and comfort cooling need annual inspections until one year is below it.
• An appliance that leaks 125 percent or more of its full charge in a calendar year must be reported to EPA by March 1 of the next year.
• A retrofit or retirement plan is due within 30 days when required, and the work is generally finished within one year.
• Records are generally kept for three years.

Since January 1, 2026, separate EPA rules under the AIM Act (40 CFR Part 84, Subpart C) also require leak repair on many appliances with 15 pounds or more of HFC refrigerant. Check EPA's pages for the current details.

Type III: low-pressure appliances

Low-pressure appliances, such as chillers using R-11, R-123 or R-245fa, run partly below atmospheric pressure. Air and moisture can leak in, so they have a purge unit to remove them.

• Evacuate to 25 mm Hg absolute before a major repair or disposal.
• For a non-major repair, pressurize to no higher than 0 psig before opening.
• If the refrigerant boils above 85 degrees F, raise the pressure with heat first. Nitrogen may then bring it up to atmospheric pressure.
• If it boils at or below 85 degrees F, do not use nitrogen or other methods that would need purging later.
• Recover the liquid first, then the vapor.
• Heat the oil before removing it, so less refrigerant leaves with the oil.
• When recharging from a deep vacuum, add vapor before liquid so water in the tubes does not freeze. Centrifugals are charged through the evaporator charging valve.
• ASHRAE Standard 15 equipment rooms using R-123 need a refrigerant sensor.