EPA 608 Exam Traps

“Must” vs. “should”: requirement vs. advice

The CFR speaks in must (mandatory) and may (permitted). When a question asks what the rules require, only a “must” answers it. Guidance language — what a good tech should do, what EPA recommends, what a manufacturer suggests — is real advice, but it is not a regulation, and it does not make an answer correct when the question asks for the rule. Three places this bites:

• Leak-checking recovery equipment: checking the device for leaks is taught as routine practice, but the CFR sets no technician check interval (see the Equipment Certification page). A choice that states a CFR-mandated frequency for that check is inventing a rule.
• “Should repair” vs. “must repair”: small-appliance leaks are the classic case — EPA does not impose the §82.157 leak-repair regime on small appliances, so a question that turns “good practice” into a repair deadline is overstating the rule.
• Manufacturer directions: equipment must be used per the manufacturer's directions unless those directions conflict with Subpart F (§82.156(g)). The manual is authoritative until it contradicts the regulation — then the regulation wins. “The manual said so” is never the final answer.

Exceptions that look like rules (and rules that look like exceptions)

• Hooking up gauges is not “opening.” Connecting/disconnecting hoses and gauges to measure pressures, add refrigerant, or recover refrigerant is expressly not “opening an appliance” (§82.152) — but it still makes you a “technician” who must be certified. Two definitions, two different answers.
• Apprentices are the only uncertified hands allowed — and only if registered with the DOL Office of Apprenticeship (or a recognized State Apprenticeship Council), closely and continually supervised by an appropriately certified technician, for a maximum of 2 years from first registration (§82.152). “My boss is certified” is not an apprentice exception.
• CO₂ is exempt from the venting ban; HFCs are not. The venting prohibition covers ODS and non-exempt substitutes (§82.154(a)); the exempt list in (a)(1) is short and specific. A choice that treats “substitute” as “exempt” fails.
• De minimis releases are excused; recovered refrigerant is not. Small releases during a good-faith recovery attempt, with required practices and certified equipment and technicians, fall outside the ban — but knowingly releasing refrigerant after it has been recovered is expressly a violation (§82.154(a)(2)–(3)).
• Mothballing suspends the clock; it does not erase it. Leak-repair timelines are suspended while an appliance is mothballed (evacuated to at least atmospheric pressure, temporarily shut down) and resume when it returns to service (§82.152; EPA leak-repair page).
• The retail sales exception is tiny. Refrigerant sales are limited to certified technicians, their employers, manufacturers, and resale into that chain (§82.154(c)); the only retail carve-out is MVAC substitute cans of 2 lb or less with a self-sealing valve. A contractor's license alone does not authorize a purchase.
• The pump-out owner exemption is narrower than it sounds. Owners servicing only their own pump-out-unit appliances are exempt from the certified self-contained equipment requirement (§82.156(f)) — not from certification, venting, or evacuation rules.

Old keys vs. current law: the four stale answers

If your study guide disagrees with the right-hand column, trust the citation, not the guide — and check the guide's print date before you trust anything else in it.

The number traps: same digits, different rules

• 0 psig vs. 5 psig: non-major openings cap at 0 psig (pressurize for low-pressure, evacuate for everything else); 5 psig is oil changes only (§82.156(a)(1)).
• 15 lb, three meanings: the §84.106 HFC leak-repair threshold; the system-dependent equipment ceiling (§82.156(e)); and the small-appliance boundary is 5 lb, not 15 — do not swap them.
• 30 days, three clocks: repair within 30 days of discovering an exceedance; a retrofit/retire plan within 30 days; a follow-up verification test within 30 days of return to normal operating conditions. Same length, different start events — read which clock the question started.
• 125% / March 1: an appliance leaking 125% or more of its full charge in a calendar year is a chronic leaker, reported to EPA by March 1 of the following year (§84.106(j), (m)(4)). First reports, for calendar 2026, are due March 1, 2027.
• 3 years, two records: disposal records for 5–50 lb appliances are kept 3 years (§82.156(a)(3)), and leak-repair records are likewise a 3-year federal floor — but that is not a 5-year rule (5 years is a state overlay in some programs, not the federal minimum).