EPA 608 Plan

Core: practice questions

5 original questions · 5 editor-approved · every choice explained.

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Blueprint-mapped questions with full rationales for every choice.

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CoreDifficulty 2/5

Since 1 January 2018, the venting prohibition in 40 CFR 82.154 has applied to refrigerant released while servicing which appliances?

  1. AThose containing any class I or class II refrigerant or a non-exempt substitute
  2. BThose containing a class I refrigerant that has not yet been fully phased out
  3. CThose containing a class I or class II refrigerant but no substitute refrigerant
  4. DThose containing more than fifty pounds of any refrigerant covered by the rule
Show answer and rationale

Correct: A. The 2018 expansion is the single most commonly missed Core fact. Section 82.154(a)(1) reaches any class I or class II refrigerant and any non-exempt substitute, with a short exemption list that includes carbon dioxide, nitrogen, water and specified hydrocarbon end-uses.

  • B — The ban was never limited to refrigerants still in production; phase-out status is irrelevant to it.
  • C — This was the position before 1 January 2018, when the rule was extended to non-exempt substitutes.
  • D — The fifty-pound threshold belongs to the leak repair rules in 82.157, not to the venting prohibition.
CoreDifficulty 3/5

What distinguishes reclaiming refrigerant from recycling it?

  1. AReclaiming returns the refrigerant to the same appliance it was removed from
  2. BReclaiming reprocesses refrigerant to a specification verified by chemical analysis
  3. CReclaiming removes the refrigerant from the appliance and stores it in a cylinder
  4. DReclaiming cleans the refrigerant by oil separation and passes through a filter-drier
Show answer and rationale

Correct: B. Reclaiming means reprocessing to new-product purity, confirmed by chemical analysis against the AHRI 700 standard. It cannot be done on a job site, which is the practical consequence the exam is testing.

  • C — That describes recovery, which is simply removing refrigerant and storing it externally.
  • D — That describes recycling, a field-level clean-up that does not meet the reclaim specification.
  • A — Where the refrigerant ends up does not define the term; the purity standard reached does.
CoreDifficulty 1/5

A recovery cylinder must not be filled beyond what proportion of its capacity?

  1. ASeventy percent, because the cylinder must be weighed before it is transported
  2. BSixty percent, because the relief valve cannot operate above that fill level
  3. CEighty percent, because liquid refrigerant expands as its temperature rises
  4. DNinety percent, because the remaining space allows vapour to be drawn off
Show answer and rationale

Correct: C. Overfilling is a rupture risk: a cylinder filled hydrostatically full has nowhere to expand into when it warms, and the vapour space is what absorbs that expansion.

  • D — Ninety percent is the small-appliance recovery threshold for a working compressor, not a fill limit.
  • A — Weighing a cylinder is required practice, but seventy percent is not the regulatory fill limit.
  • B — Relief valves are not rated by fill percentage, and sixty percent is not the figure in the rule.
CoreDifficulty 2/5

Ranked from highest ozone depletion potential to lowest, how do CFCs, HCFCs and HFCs compare?

  1. AHCFCs are highest, CFCs are lower, and HFCs have none because they lack fluorine
  2. BHFCs are highest, CFCs are lower, and HCFCs have none because they lack bromine
  3. CAll three are equal, because each contains a halogen that reaches the stratosphere
  4. DCFCs are highest, HCFCs are lower, and HFCs have none because they lack chlorine
Show answer and rationale

Correct: D. Chlorine is what destroys stratospheric ozone. CFCs carry the most, HCFCs carry less because hydrogen makes them break down lower in the atmosphere, and HFCs carry none at all.

  • A — The order is inverted, and fluorine is not the ozone-depleting element in these compounds.
  • B — HFCs have an ozone depletion potential of zero, and bromine is not present in any of the three.
  • C — They are not equal; the whole point of the HCFC and HFC transitions was to lower the potential.
CoreDifficulty 2/5

Why does EPA's Core topic list require nitrogen rather than oxygen or compressed air for pressurised leak detection?

  1. AOxygen and compressed air can form a combustible mixture with refrigerant oil
  2. BOxygen and compressed air dissolve into the refrigerant and contaminate the charge
  3. COxygen and compressed air cannot reach the pressure a leak test actually requires
  4. DOxygen and compressed air are not permitted inside a certified recovery machine
Show answer and rationale

Correct: A. Compressing oxygen in the presence of hydrocarbon oil is an explosion risk, which is why the rule pairs the nitrogen requirement with a pressure regulator and a relief valve.

  • B — Contamination is a genuine concern with air and moisture, but it is not the safety reason given.
  • C — Both can reach test pressures easily; capability is not the objection to using them.
  • D — The restriction concerns pressurising the appliance for a leak test, not recovery machine internals.

Primary references

  1. 40 CFR Part 82 Subpart F — Recycling and Emissions Reduction — Office of the Federal Register (eCFR) · government · retrieved 2026-09-22, verified 2026-09-22
  2. Section 608 Test Topics — United States Environmental Protection Agency · primary · retrieved 2026-09-22, verified 2026-09-22