EPA 608 certification is required under Section 608 of the Clean Air Act for technicians who work on stationary refrigeration and air-conditioning equipment. This guide explains who needs it, how the exam is built, what you need to pass and how to prepare.

Who needs it

Anyone who maintains, services, repairs or disposes of stationary air-conditioning or refrigeration equipment in a way that could release refrigerant needs to be certified. That includes attaching and removing gauges, adding refrigerant and opening a system. Anyone who disposes of equipment other than small appliances needs it too. Sellers must also see proof of certification before selling you most refrigerants.

Motor vehicle air conditioning is covered by a different certification, Section 609.

The four sections

The exam has four sections of 25 multiple-choice questions each:

Section	What it covers
Core	Ozone depletion, regulations, recovery, recycling and reclaiming, cylinders, safety and the refrigeration cycle. Required for every certification.
Type I	Small appliances: factory-sealed equipment with 5 pounds of refrigerant or less.
Type II	Medium-, high- and very high-pressure appliances, such as residential split systems, heat pumps and commercial refrigeration.
Type III	Low-pressure appliances, mainly centrifugal chillers.

You pass Core plus each type you need. Passing Core and all three types gives you Universal certification.

Passing scores

On the standard proctored, closed-book exam you need 18 of 25 (70%) in each section you take. Sections are scored separately, so you can pass Core and Type II even if you miss Type I.

Some certifying organizations offer Type I alone as an open-book test by mail or online. That version needs 84% (21 of 25) and can’t count toward Universal.

Who gives the exam

The exam is given by EPA-approved certifying organizations, not by EPA itself. Many trade schools, supply houses and training organizations offer it, usually with a proctor, in person or online. Fees vary by provider.

Does it expire?

No. EPA 608 certification doesn’t expire. Keep a copy of your certificate at your place of business.

How to prepare

1. Start with Core. Everyone needs it, and its topics (venting rules, recovery, cylinders, safety) show up in the type sections too.
2. Learn the numbers. Evacuation levels, leak-rate thresholds, the 80% cylinder fill limit and small appliance recovery percentages are common questions. See the evacuation levels table.
3. Take full 25-question practice sections and aim well above 18, so a few tricky questions on test day don’t matter.
4. Review every miss until you understand why the right answer is right.

Start with the free questions: Core, Type I, Type II and Type III.