EPA 608 Core Practice Test
Updated October 26, 2026
Everyone taking the EPA 608 exam takes Core, plus the type or types for the equipment they work on. Core has 25 multiple-choice questions, and on the standard proctored exam you need 18 right (70%) to pass. Try the free questions below. Each one shows the answer and why as soon as you pick.
What Core covers
- Ozone depletion and which refrigerants cause it.
- The Clean Air Act, the Montreal Protocol and the rules against venting refrigerant.
- The difference between recovering, recycling and reclaiming.
- Recovery cylinders, shipping and labeling.
- Dehydration and evacuation, and the refrigeration cycle.
- Safety: pressure, heat and personal protective equipment.
Free EPA 608 Core practice questions
-
Which part of the atmosphere contains the ozone layer that CFC and HCFC refrigerants damage?Answer: BThe protective ozone layer is in the stratosphere. CFC and HCFC molecules are stable enough to drift up there, where ultraviolet light breaks them apart and the released chlorine destroys ozone.
-
Which element in CFC and HCFC refrigerants is responsible for destroying ozone?Answer: CChlorine is the ozone-depleting element. A single chlorine atom can break down many ozone molecules. HFCs contain no chlorine, so their ozone depletion potential is zero, although many have a high global warming potential.
-
Which refrigerant type has the highest ozone depletion potential?Answer: DCFCs contain the most chlorine and are the most stable, so they have the highest ozone depletion potential. HCFCs have a lower ODP because the hydrogen makes them break down sooner, and HFCs and HFOs have an ODP of zero.
-
Refrigerant has been reprocessed to the purity standard of AHRI 700 and verified by chemical analysis. This refrigerant has been:Answer: AReclaiming means reprocessing refrigerant to new-product purity (AHRI 700) and verifying it with chemical analysis, usually at a reclaimer's facility. Recovering only removes refrigerant from a system, and recycling cleans it by oil separation and filter-driers, usually on site, without meeting AHRI 700.
-
A refillable recovery cylinder should not be filled beyond what share of its capacity by liquid volume?Answer: CFill recovery cylinders to no more than 80% of capacity by liquid volume. The empty space leaves room for the liquid to expand as it warms. An overfilled cylinder can become liquid-full and rupture.
-
What colors identify a DOT-approved refrigerant recovery cylinder?Answer: BRecovery cylinders are gray with a yellow top (shoulder). They are designed for refilling and have both a liquid and a vapor valve. Disposable cylinders used for new refrigerant must never be used for recovery.
-
Which gas should be used to pressurize a system for leak testing?Answer: CUse dry nitrogen, with a pressure regulator and relief valve. Never use oxygen or compressed air: mixed with compressor oil under pressure, they can cause an explosion. A trace of the system's refrigerant may be added so an electronic leak detector can find leaks.
-
When is it legal to knowingly vent CFC or HCFC refrigerant to the atmosphere during service?Answer: DThe Clean Air Act prohibits knowingly venting ozone-depleting refrigerants and their substitutes. Only small de minimis releases that happen while following required practices, such as connecting and disconnecting hoses during proper recovery, are allowed.
Next steps
After Core, practise the type you need: Type I for small appliances, Type II for high-pressure systems such as residential split systems, or Type III for low-pressure chillers. Pass all four sections for Universal certification. See the EPA 608 certification guide for how the exam works.
Pass the EPA 608 exam on your first try
- All 168 questions across Core, Type I, Type II and Type III
- An explanation for every answer, with the rule or principle behind it
- Unlimited practice exams per section, scored like the real test (18 of 25 to pass)