EPA 608 Type 3 Practice Test: 50 Free Questions

Answer: A. Only the R-123 chiller.

Why: Type III follows the refrigerant's pressure class, not the style of equipment. EPA lists R-123 as a low-pressure refrigerant (liquid saturation pressure below 45 psia at 104°F) and R-22 as a high-pressure one. Low-pressure appliances are Type III; high-pressure appliances are Type II.

Why not the others: "Chiller" doesn't decide the Type, so "every chiller is Type III" and "chillers are Type II" both fail. Picking only the R-22 chiller flips the two refrigerants. A Universal card covers both machines.

Source: 40 CFR 82.152 (definitions), low-pressure and high-pressure appliance · 40 CFR 82.161, (a)(1)(ii)–(iii)

Answer: D. 25 mm Hg absolute.

Why: Removing a compressor is a major repair. For low-pressure appliances, Table 1 lists one level, 25 mm Hg absolute, in both the pre- and post-November 15, 1993 equipment columns. There's no 200-lb split for low-pressure appliances.

Why not the others: 15 and 10 in. Hg come from the medium- and high-pressure rows, where charge size matters. 0 psig is the ceiling for certain non-major repairs, not for this job.

Source: 40 CFR 82.156, Table 1 · 40 CFR 82.152 (definitions), major maintenance, service, or repair

Answer: C. About 29 in. Hg vacuum.

Why: 25 mm is 0.98 in. Table 1 measures vacuum against a 29.9 in. Hg atmosphere, so 29.9 − 0.98 ≈ 28.9 in. Hg vacuum. That's close to a full vacuum. It's also 25,000 microns.

Why not the others: 25 in. Hg vacuum is the classic mm/inches mix-up; it still leaves about 5 in. Hg absolute in the shell. "About 1 in. Hg vacuum" confuses the absolute reading with the vacuum reading. 15 in. Hg vacuum is a medium-pressure level.

Source: 40 CFR 82.156, Table 1 header and low-pressure row

Answer: B. No, because the opening isn't more than 4 square inches of flow area.

Why: Without a major component removed, work is major only if it uncovers more than 4 square inches of flow area for more than 15 minutes. Both conditions have to be true. A 1.5-square-inch opening fails the size test no matter how long it stays open.

Why not the others: The time condition alone isn't enough. Not every opening of the circuit is major; the definition sets the line. Charge size isn't part of the definition.

Source: 40 CFR 82.152 (definitions), major maintenance, service, or repair

Answer: D. Cover the openings, because isolation isn't possible.

Why: For a non-major repair on a low-pressure appliance, the rule says to pressurize it to no higher than 0 psig and to cover openings when isolation isn't possible. Covering the opening keeps air and moisture out and refrigerant in.

Why not the others: 25 mm Hg absolute is the full Table 1 level for major repairs. Nitrogen to 5 psig breaks two rules: 5 psig is the oil-change allowance, and nitrogen isn't allowed for refrigerants that boil at or below 85°F, like R-123.

Source: 40 CFR 82.156, (a)(1)(ii)

Answer: A. Transfer the liquid refrigerant first, then recover the remaining vapor.

Why: EPA's Type 3 list says recovering liquid at the start speeds up recovery, and that vapor still has to be recovered afterward. A pound of liquid moves far faster than the same pound as low-pressure vapor.

Why not the others: Staying on vapor has it backward. Nitrogen mixes a noncondensable into the refrigerant you're recovering. Shutting off the condenser water cools the refrigerant and lowers its pressure, which slows recovery; EPA lists heating the source, not cooling it, as a way to speed things up.

Source: EPA Test Topics, Type 3 → Recovery Techniques; Type 2 → Recovery Techniques

Answer: B. Warm oil holds less dissolved refrigerant, so less refrigerant leaves with the oil.

Why: Refrigerant dissolves in chiller oil. EPA's Type 3 list says to heat the oil to 130°F before removing it to minimize refrigerant release. Heating drives the refrigerant out of the oil and back into the system.

Why not the others: Warm oil may drain more easily, but that isn't the reason EPA gives. Freezing oil isn't the concern, and no rule requires hot oil for disposal.

Source: EPA Test Topics, Type 3 → Recovery Techniques

Answer: A. At that pressure R-123's saturation temperature is far below 32°F, so water in the tubes can freeze and split them.

Why: As shell pressure drops, so does the refrigerant's saturation temperature. At 25 in. Hg vacuum, R-123 is well below water's freezing point, so standing water in the tubes can freeze. EPA's Type 3 topic list says to circulate or remove water during evacuation to prevent freezing.

Why not the others: R-123 doesn't decompose from low pressure. A rupture disc relieves overpressure, not vacuum. The purge unit isn't what's at risk here; the tubes are.

Source: EPA Test Topics, Type 3 → Recovery Techniques · Hudson Technologies pressure-temperature charts (refrigerant-specific charts)

Answer: B. The liquid flashes to vapor at the very low pressure, and the cooling can freeze water in the tubes.

Why: Liquid entering a deep vacuum boils instantly and gets very cold. EPA's Type 3 list says to introduce vapor before liquid to prevent freezing water in the tubes. Once vapor has raised the pressure past the point where the refrigerant boils at 32°F, liquid can follow.

Why not the others: Liquid-first ignores the freeze risk. Liquid entering a vacuum doesn't overpressure the shell, so the rupture disc isn't the issue. The purge unit removes noncondensables, not liquid refrigerant.

Source: EPA Test Topics, Type 3 → Recharging Techniques

Answer: D. Through the evaporator charging valve.

Why: EPA's Type 3 list names the evaporator charging valve as the place to charge centrifugals.

Why not the others: The purge unit removes noncondensables; it isn't a charging port. The rupture disc is a pressure-relief device and should never be used as a service connection.

Source: EPA Test Topics, Type 3 → Recharging Techniques

Answer: B. About 32°F.

Why: On a pressure-temperature chart, R-11 at about 18 in. Hg vacuum (about 5.8 psia) boils at roughly 32°F. Reading a low-pressure P-T chart in inches of vacuum is part of EPA's Type 3 refrigeration topic.

Why not the others: 0°F is far deeper in vacuum. About 75°F is R-11's boiling point at atmospheric pressure (0 psig), not at 18 in. of vacuum.

Source: EPA Test Topics, Type 3 → Refrigeration · Hudson Technologies pressure-temperature charts (refrigerant-specific charts)

Answer: D. Treat it as a sign of a leak letting air in, then find and repair the leak.

Why: Much of a low-pressure chiller runs below atmospheric pressure, so leaks pull air and moisture in. The purge unit removes those noncondensables. EPA lists excessive purging as a sign of leakage into a low-pressure system.

Why not the others: Resetting the timer or closing the discharge hides the symptom and leaves the air in. Adding refrigerant treats the loss without fixing the leak, and each addition feeds the leak-rate calculation.

Source: EPA Test Topics, Type 3 → Leak Detection · Trane CVHE/CVHF/CVHG IOM manual (CVHE-SVX02H-EN, 2015), p. 30 (purge removes noncondensables)

Answer: B. On the evaporator side (suction); it breaks if shell pressure goes above about 15 psig.

Why: That manual puts the rupture disk on the suction elbow and says it breaks when evaporator pressure goes above 15 psig. Low-pressure shells aren't built for high internal pressure, which is why leak-test pressure has to stay well below the disc. Other models and newer relief assemblies can differ, so check the unit in front of you.

Why not the others: "High side" placement is a common error in free study material. 10 psig and 50 psig aren't the disc rating. A rupture disc relieves pressure, not vacuum.

Source: Trane CVHE/CVHF/CVHG IOM manual (CVHE-SVX02H-EN, 2015), p. 31

Answer: D. Dry nitrogen through a regulator, kept well below the rupture-disc rating and within the manufacturer's limit.

Why: EPA ranks hot water or a built-in pressurizing device first and nitrogen second, and calls for nitrogen with a pressure regulator rather than compressed air. The allowable nitrogen pressure is equipment-specific: the cited Trane manual limits this product line to 8 psig and describes a rupture disk that relieves at about 15 psig evaporator pressure. Follow the nameplate and current manual for the unit being serviced.

Why not the others: 15 psig and 25 psig are not defensible generic leak-test settings; on the cited Trane product line they reach or exceed the documented relief point. Shop air adds moisture and oxygen; EPA's public test topics specify nitrogen, not compressed air, for leak detection.

Source: EPA Test Topics, Type 3 → Leak Detection; Core → Safety · Trane CVHE/CVHF/CVHG IOM manual (CVHE-SVX02H-EN, 2015), pp. 9, 31

Answer: B. A certified technician does a leak inspection to find the leaks, and they're repaired, unless the owner chooses to retrofit or retire the chiller.

Why: R-123 is an ozone-depleting refrigerant and the charge is over 50 lb, so 40 CFR 82.157 applies. Comfort cooling triggers above 10%. The owner has 30 days to find and fix the leaks, and the leak inspection must be done by a certified technician. Retrofitting or retiring under a written plan is the alternative.

Why not the others: 15% is the pre-2019 comfort-cooling figure. The chronic-leaker report is for 125% or more in a calendar year. Retirement has a one-year plan timeline, not 30 days.

Source: 40 CFR 82.157, (c)(2)(iii), (d), (d)(1)

Answer: A. That valve doesn't have to be inspected, but a certified technician must inspect all other visible, accessible components.

Why: The rule excuses components where someone would have to be raised more than 2 meters above a support surface, along with insulated, inaccessible, or unsafe components. The inspection itself must be done by a certified technician.

Why not the others: The rule lists exceptions, so "no exceptions" is wrong. One hard-to-reach valve doesn't cancel the whole inspection. Any employee won't do; the rule names a certified technician.

Source: 40 CFR 82.157, (g)(2)–(g)(3)

Answer: B. Every time refrigerant is added, except right after a retrofit, a new installation, or an addition that counts as a seasonal variance.

Why: Under 40 CFR 82.157(b), the owner calculates the leak rate every time refrigerant is added, with only those three exceptions. Whoever adds the refrigerant has to give the owner the service documentation needed to do it.

Why not the others: There's no annual-only schedule and no size cutoff for the addition. Purge behavior isn't the trigger; adding refrigerant is.

Source: 40 CFR 82.157, (b)

Answer: B. 15%, which is over the 10% comfort-cooling threshold, so repair (or a retrofit or retirement plan) is required.

Why: Rolling average: pounds added over the past 365 days ÷ full charge × 100. So 90 ÷ 600 × 100 = 15%. Office cooling is comfort cooling, and comfort cooling triggers above 10%.

Why not the others: 6.7% divides the charge by the refrigerant added (600 ÷ 90). 20% is the commercial refrigeration threshold. 1.5% slips a decimal.

Source: 40 CFR 82.152 (definitions), leak rate, rolling average method · 40 CFR 82.157, (c)(2)(iii)

Answer: C. 30% for industrial process refrigeration.

Why: EPA counts an appliance as industrial process refrigeration when 50% or more of its operating capacity serves the industrial process. At 55%, this chiller is industrial process refrigeration, with a 30% threshold.

Why not the others: 10% would apply only if comfort cooling were the larger use. Commercial refrigeration means retail food and cold storage. There's no averaging rule.

Source: 40 CFR 82.152 (definitions), industrial process refrigeration · 40 CFR 82.157, (c)(2)(ii)

Answer: A. 40 CFR 84.106 (the AIM Act rule), at 10% for comfort cooling.

Why: R-245fa is an HFC, not an ozone-depleting substance, so 40 CFR 82.157 doesn't reach it. Since January 1, 2026, 40 CFR 84.106 covers appliances holding 15 lb or more of an HFC or a substitute with a GWP above 53. Comfort cooling is 10% under that rule too. An R-123 chiller would stay under 82.157.

Why not the others: 40 CFR 82.157 is the wrong rulebook for an HFC. "No rule" was true for HFC equipment before 2026. 20% is the commercial refrigeration threshold.

Source: 40 CFR 82.157, (a) · 40 CFR 84.106, (a), (c)(2)(iii)

Answer: A. Initial test before any refrigerant is added back; follow-up within 10 days of the chiller reaching normal operating conditions.

Why: When a repair required evacuation, the initial verification test comes before any refrigerant goes back in. The follow-up test comes within 10 days of the chiller reaching normal operating characteristics and conditions.

Why not the others: 12 months and 30 days aren't the test windows. Both tests are required on each repaired leak.

Source: 40 CFR 82.157, (e)(1)(ii), (e)(2)

Answer: C. A written plan within 30 days, with the work finished within one year of the plan's date.

Why: The owner must write a retrofit or retirement plan within 30 days, and the work must be finished within one year of the plan's date (no more than 13 months from when the plan was required), unless EPA grants more time.

Why not the others: A one-year plan and five-year retirement stretch both deadlines. Retirement still needs a plan. Ten days isn't in the rule.

Source: 40 CFR 82.157, (h)(1), (h)(5)(i)

Answer: B. If no refrigerant is added for 12 months after the repair, or the required leak inspections find no leaks.

Why: Under 40 CFR 82.157(d)(2), repairs are presumed successful if there's no further refrigerant addition for 12 months after the repair, or if the required leak inspections find no leaks. The leak-rate calculation at the next addition also confirms it.

Why not the others: The initial test shows the repair held at that moment; the presumption comes later. Purge cycles and EPA site visits aren't the test.

Source: 40 CFR 82.157, (d)(2)

Answer: A. It's left out, because destruction efficiency is 98% or higher, as long as the records and EPA notice are in place.

Why: Purged refrigerant destroyed at a verifiable 98% efficiency or better isn't counted toward the leak rate. The owner has to keep monitoring records and notify EPA within 60 days of first using the exclusion.

Why not the others: There's no doubling and no 10-lb cutoff. Without the destruction, purged refrigerant would count as loss.

Source: 40 CFR 82.157, (k), (l)(9), (m)(5)

Answer: D. Detect refrigerant within the acceptable exposure level, set off alarms inside the room and outside each entrance, and start the mechanical ventilation.

Why: EPA's Type 3 list names the ASHRAE Standard 15 equipment-room refrigerant sensor for R-123. A manufacturer's manual spells out what that setup typically includes: a monitor that alarms within the acceptable exposure level, audible and visual alarms inside the room and outside every entrance, and mechanical ventilation the monitor can start.

Why not the others: A log alone warns no one. Stopping the pumps doesn't clear the air. The rupture disc protects the chiller from overpressure; it has nothing to do with room air.

Source: EPA Test Topics, Type 3 → Safety · Trane CVHE/CVHF/CVHG IOM manual (CVHE-SVX02H-EN, 2015), p. 8

Answer: A. R-134a.

Why: EPA names R-11, R-113, R-123, and R-245fa as low-pressure examples. R-134a is one of its medium-pressure examples (45 to 170 psia at 104°F), so R-134a equipment is Type II.

Why not the others: R-11, R-113, and R-245fa are all on EPA's low-pressure list.

Source: 40 CFR 82.152 (definitions), low-pressure and medium-pressure appliance

Answer: C. Type III (or Universal).

Why: Type III covers people who maintain, service, repair, or dispose of low-pressure appliances. The only disposal exemption is for small appliances, motor vehicle air conditioners, and MVAC-like appliances.

Why not the others: "No certification" applies only to those exempt categories. Type I is small appliances. Section 609 is motor vehicle A/C.

Source: 40 CFR 82.161, (a)(1)(iii), (a)(1)(vii)

Answer: B. Keep recovering vapor until the shell reaches 25 mm Hg absolute, and confirm that level before opening.

Why: A big shell at 0 psig still holds a lot of refrigerant as vapor. EPA's Type 3 list stresses recovering vapor as well as liquid, Table 1 sets 25 mm Hg absolute for low-pressure appliances, and the tech must verify the level has been reached before opening.

Why not the others: Opening at 0 psig releases the vapor still inside. Nitrogen contaminates what's left. Sending refrigerant out through the purge on purpose is venting.

Source: EPA Test Topics, Type 3 → Recovery Techniques · 40 CFR 82.156, (a) and Table 1

Answer: D. For refrigerants that boil at or below 85°F, the rule bars methods like nitrogen that have to be purged out later.

Why: The rule draws its line at an 85°F boiling point. At or below it, low-pressure appliances can't be pressurized with methods such as nitrogen that require later purging. Nitrogen left inside is a noncondensable that would have to be purged out later.

Why not the others: The rule isn't about chemistry or speed, and there's no 10 psig nitrogen allowance.

Source: 40 CFR 82.156, (a)(1)(ii) · Hudson Technologies pressure-temperature charts (refrigerant-specific charts)

Answer: C. Heat to raise the pressure as far as it will go, then nitrogen from there up to atmospheric.

Why: Above 85°F, the rule requires heat first and allows nitrogen to finish the rise to atmospheric pressure. R-113 is on EPA's low-pressure list, so the rule applies.

Why not the others: Heat can't be skipped. R-113 chillers aren't exempt. 25 mm Hg absolute is the major-repair level, not the non-major pressurizing rule.

Source: 40 CFR 82.156, (a)(1)(ii) · 40 CFR 82.152 (definitions), low-pressure appliance · Hudson Technologies pressure-temperature charts (refrigerant-specific charts)

Answer: A. 0 psig.

Why: When leaks make the Table 1 level impossible or would badly contaminate the refrigerant, the tech isolates leaking parts where possible, takes non-leaking parts to the Table 1 level, and takes leaking parts as low as possible without substantial contamination. That level can't be higher than 0 psig.

Why not the others: 5 psig is the oil-change allowance. 10 and 15 psig aren't ceilings anywhere in this rule.

Source: 40 CFR 82.156, (a)(2)

Answer: C. Evacuate only that section to the required level, confirm the level, then open it.

Why: Technicians can evacuate either the whole appliance or just the part being serviced, when that part's refrigerant can be isolated to a system receiver. Either way, the tech must verify the required level has been reached before opening.

Why not the others: Evacuating the whole chiller is more than the rule requires. Opening without evacuating skips the part being opened. 0 psig is the non-major ceiling, not the level for a major repair.

Source: 40 CFR 82.156, (a) · 40 CFR 82.152 (definitions), system receiver

Answer: D. The tech doesn't need certified self-contained recovery equipment for these chillers.

Why: People who service only appliances they own that have pump-out units are exempt from the requirement to use certified self-contained recovery equipment. System-dependent equipment is barred on appliances over 15 lb unless it's permanently attached as a pump-out unit.

Why not the others: The exemption covers the separate machine, so the tech doesn't have to bring one. Pump-out units are the allowed case over 15 lb, not a banned one. Owning the equipment doesn't remove the technician-certification requirement.

Source: 40 CFR 82.156, (e), (f) · 40 CFR 82.161, (a)(1)(iii)

Answer: D. Nothing further; recovered refrigerant can go into another appliance owned by the same person.

Why: Refrigerant can go back into the appliance it came from, or into another appliance owned by the same person, without recycling or reclaiming. "Person" includes organizations like a university.

Why not the others: Reclaiming is required when refrigerant changes owners. Destruction and recycling aren't required here.

Source: 40 CFR 82.156, (h) · 40 CFR 82.152 (definitions), person

Answer: A. No; the recovery must use recovery or recycling equipment certified under EPA's rules.

Why: Before opening or disposing of these appliances, refrigerant must be evacuated using a recovery or recycling machine certified under 40 CFR 82.158. A homemade rig isn't certified equipment, whatever vacuum it pulls.

Why not the others: Reaching the level doesn't fix uncertified equipment. The tech's card and the chiller's size don't change the equipment rule.

Source: 40 CFR 82.156, (a)

Answer: A. 20 in. Hg vacuum.

Why: R-123's saturation pressure at 32°F is about 4.7 psia, roughly 20.3 in. Hg vacuum. 20 in. Hg vacuum (about 4.9 psia) is just past that point, so the refrigerant now boils at about 33°F. In practice, keep some margin and follow the manufacturer.

Why not the others: At 29 and 25 in. Hg vacuum, R-123 boils far below freezing. 5 psig is above freezing too, but it isn't the lowest reading listed.

Source: EPA Test Topics, Type 3 → Recharging Techniques · Hudson Technologies pressure-temperature charts (refrigerant-specific charts)

Answer: B. Only the refrigerant the chiller is built for, R-123 per the nameplate; don't mix refrigerants.

Why: EPA's Core list stresses avoiding mixed refrigerants, and chiller makers tell techs to use the refrigerant on the unit nameplate. A mix can't be reclaimed as either refrigerant and changes how the machine runs.

Why not the others: Sharing a pressure class doesn't make refrigerants interchangeable. A blend, or R-11 with a note, creates exactly the mix EPA warns about.

Source: EPA Test Topics, Core → Recovery Techniques · Trane CVHE/CVHF/CVHG IOM manual (CVHE-SVX02H-EN, 2015), p. 3 (nameplate refrigerant)

Answer: C. About 7 in. Hg vacuum.

Why: R-123 boils at about 82°F at atmospheric pressure, so below that temperature it sits in a vacuum. At 70°F its saturation pressure is about 11.4 psia, roughly 6.6 in. Hg vacuum. That's why low-pressure chillers draw air in through leaks.

Why not the others: 10 psig would take a temperature well above 100°F. 0 psig matches about 82°F. 29 in. Hg vacuum is near the recovery level, not a resting chiller.

Source: 40 CFR 82.152 (definitions), low-pressure appliance · Hudson Technologies pressure-temperature charts (refrigerant-specific charts)

Answer: B. Outdoors, following ASHRAE Standard 15 and local code, where the discharge won't spray anyone.

Why: A manufacturer's ASHRAE 15 guidance says the purge discharge and the rupture disk must be piped to the outdoors, ending where a release won't spray anyone and can't be blocked or fill with rainwater.

Why not the others: A floor drain puts refrigerant into the building. Piping relief back to the low side defeats the relief device. A cylinder on the line would block the relief path.

Source: Trane CVHE/CVHF/CVHG IOM manual (CVHE-SVX02H-EN, 2015), pp. 8, 30–31

Answer: C. The rupture disk can fatigue and break at less than its roughly 15 psig rating.

Why: The cited manufacturer warns that ambient temperatures above 104°F can fatigue the unit's rupture disk so it may break at a pressure lower than its approximately 15 psig design relief point. That warning is product-specific, so use the current manual for the chiller in front of you.

Why not the others: Heat can reduce the rupture disk's margin rather than sealing it. The purge unit removes noncondensables; it doesn't add refrigerant or protect the relief device from excessive ambient temperature.

Source: Trane CVHE/CVHF/CVHG IOM manual (CVHE-SVX02H-EN, 2015), p. 16

Answer: A. A self-contained breathing apparatus (SCBA).

Why: Refrigerant vapor displaces oxygen. EPA's Core safety list names SCBA for extreme cases, and a chiller manual notes that SCBA should be kept near the equipment room where codes require it. Better still, let the mechanical ventilation clear the room first.

Why not the others: A dust mask and glasses don't supply air. The purge unit has nothing to do with the room's air.

Source: EPA Test Topics, Core → Safety · Trane CVHE/CVHF/CVHG IOM manual (CVHE-SVX02H-EN, 2015), p. 8

Answer: B. Detects 10 ppm, alerts the owner at 100 ppm, has sensors near the compressor, evaporator, and condenser, and is audited or calibrated every year.

Why: A continuously monitoring system that's audited or calibrated every year can replace the quarterly or annual inspections. A room-air system must be indoors, have sensors near high-risk components, detect 10 ppm, and alert the owner at 100 ppm.

Why not the others: 100 ppm detection with a 1,000 ppm alert and five-year calibration misses the required levels and the annual audit. "Any hardwired detector" has no specs. A log-only system never alerts anyone.

Source: 40 CFR 82.157, (g)(4)(i)

Answer: D. Every three months, until four quarters in a row show it hasn't leaked above 30%.

Why: Industrial process refrigeration and commercial refrigeration appliances with 500 lb or more get quarterly leak inspections until the owner can show four straight quarters under the threshold.

Why not the others: Annual inspections apply to smaller systems and to comfort cooling. Monthly isn't in the rule. Verification tests don't replace the inspection schedule.

Source: 40 CFR 82.157, (g)(1)(i)

Answer: D. The date, the method or methods used, the location of each leak found, and a certification that all visible and accessible parts were inspected.

Why: Technicians who do leak inspections must give the owner documentation with the inspection date, methods, each leak's location, and a certification that all visible and accessible parts were inspected. The owner keeps it at least three years.

Why not the others: The rule puts a duty on the tech, so "nothing" fails. A card copy isn't an inspection record. A leak-free statement isn't what's required, and may not be true.

Source: 40 CFR 82.157, (l)(3), (l)

Answer: A. 6%.

Why: The annualizing method uses the shorter of the days since the last addition or 365. So (30 ÷ 500) ÷ (365 ÷ 365) × 100 = 6%. That's under the 10% comfort-cooling threshold.

Why not the others: 5.5% divides by 400 ÷ 365 instead of capping the days at 365. 6.6% multiplies by 400 ÷ 365. 30% forgets to divide by the full charge.

Source: 40 CFR 82.152 (definitions), leak rate, annualizing method · 40 CFR 82.157, (c)(2)(iii)

Answer: C. As a seasonal variance, which isn't used in the leak-rate calculation if the owner keeps the required records.

Why: EPA defines a seasonal variance as refrigerant removed because of a seasonal change in ambient conditions, then added back in an amount no greater than what was removed, within one 12-month period. Owners don't calculate a leak rate for that addition but must document that they're using the flexibility.

Why not the others: The addition is smaller than the removal, so it isn't treated as leak makeup. There's no 10-lb rule, and nothing here requires reclaimed refrigerant.

Source: 40 CFR 82.152 (definitions), seasonal variance · 40 CFR 82.157, (b), (l)(10)

Answer: C. An estimate from the compressor motor's horsepower.

Why: EPA allows four methods: the manufacturer's figure, a calculation from component sizes, refrigerant density, and piping volume, actual measurements, or an established range using its midpoint. Motor horsepower isn't one of them.

Why not the others: The manufacturer's figure, the component calculation, and actual measurements are all on EPA's list.

Source: 40 CFR 82.152 (definitions), full charge

Answer: D. An itemized procedure for converting to the new refrigerant, including compatibility changes, and a schedule of no more than one year.

Why: A retrofit or retirement plan must list, among other things, an itemized conversion procedure with compatibility changes, plans for the recovered refrigerant, and a schedule of no more than one year. It's signed by an authorized company official and kept on site.

Why not the others: The rule doesn't require a manufacturer letter, an exam score, or advance EPA approval of the plan.

Source: 40 CFR 82.157, (h)(2)–(h)(3)

Answer: C. Its refrigerant is evacuated to at least atmospheric pressure and it's temporarily shut down; the repair deadlines pause until refrigerant is added again.

Why: To mothball means to evacuate the refrigerant to at least atmospheric pressure and temporarily shut the appliance down. The repair time frames pause while it's mothballed and start again the day refrigerant is added back. The owner keeps records of both dates.

Why not the others: Shutting down with the charge inside is an ordinary shutdown, not mothballing. Mothballing is temporary, so retirement and cancelled deadlines are wrong.

Source: 40 CFR 82.152 (definitions), mothball · 40 CFR 82.157, (d)(3), (l)(8)

Answer: C. Report it to EPA by March 1, 2027, under the HFC leak-repair rule, 40 CFR 84.106.

Why: Under 40 CFR 84.106, appliances holding 15 lb or more of a covered HFC that leak 125% or more of their full charge in a calendar year must be reported to EPA by March 1 of the following year. R-245fa is an HFC, so 82.157 doesn't apply.

Why not the others: "Nothing" was true for HFC equipment before 2026. Ten days isn't the deadline. 40 CFR 82.157 is the ozone-depleting-refrigerant rule.

Source: 40 CFR 84.106, (j), (m)(4)