Pass608

    A2L practice test: 40 questions on A2L and A3 refrigerants

    The Pass608 A2L/A3 set is 40 original multiple-choice questions on A2L and A3 refrigerants, written from EPA's SNAP rules and the CFR. Ten are free once you make a free account; all 40 come with both paid tiers.

    Start the 10 free A2L questions — free account, no card.

    What the 40 questions cover

    AreaQuestionsWhat they test
    ASHRAE 34 safety groups5What the letter and number mean, the 400 ppm toxicity line, the 10 cm/s limit for 2L, how blends are classed
    Which refrigerant is which6R-32, R-454B and the HFOs as A2L; R-410A as A1; propane, isobutane and R-441A as A3; R-123 as B1
    GWP as EPA lists it4R-32, R-454B and propane, compared with R-410A and R-134a
    SNAP use conditions8New equipment only, UL 60335-2-40 3rd edition, room-size charge limits, labels, red service ports, ductwork, servicing installed systems
    Technician safety6What EPA advises (spark-proof tools, recovery equipment for flammables, the 1/4 LFL line, extinguisher), Appendix B4 recovery equipment, RCRA
    Certification and venting5Why 608 covers A2Ls, the venting ban, hydrocarbon exemptions, the R-22a retrofit ban
    A3 charge limits3Vending machines, room AC, household refrigerators
    Pressure classes3The refrigerants EPA's rule names as examples

    Each question comes with an explanation. The 10 free ones are drawn from across the set. For the rules themselves, with sources, read the A2L refrigerants guide.

    Why practice A2L now

    EPA wrote in 2021 that its 608 test bank "already includes questions concerning A2L refrigerants" (86 FR 24468). The 2026 part is reported, not published by EPA. ESCO Institute offers both a "2018" and a "2026" EPA exam. ACHR News reported on Sept 19, 2026, quoting ESCO, "the addition of general knowledge questions on A2L and A3 refrigerants", and that old-bank exams "can be administered only through Jan. 1, 2027". EPA has not posted the change as of Sept 24, 2026, and it has published no A2L topic list for the exam. So this set is written to EPA's A2L rules, not to a guess at the bank. Details: the 2026 EPA 608 question bank.

    What you get

    • Free account: 10 A2L/A3 questions, plus the free Core run.
    • Core + Type II, $15 one-time: all 40 A2L/A3 questions, plus the Core and Type II material.
    • Universal, $29 one-time: all 40, plus all four sections and 100-question Universal mocks.
    • Upgrade from Core + Type II to Universal: $14.
    • 7-day money-back on each charge. See pricing.

    From Jan 1, 2027, the reported cut-over date, our full mocks mix A2L/A3 questions into the Core and Type sections by default.

    What this set is not

    • Not a certification. We found no federal A2L certification; the law requires Section 608 certification (40 CFR 82.161). EPA sets the rules and keeps its question bank secret. The 87 approved programs (EPA list, Aug 20, 2026) give the test and issue the card; see EPA 608 certification. Pass608 is an independent study tool.
    • Not EPA's questions. Every question is original.
    • Not hands-on training. This is exam-level knowledge. Working on flammable systems takes supervised training.

    Start the 10 free A2L questions — free account, no card.

    Sources