10.14 - Optional Remediation Examination Answers

Purpose: Detailed answers and explanations for 10.13 - Optional Remediation Examination.md
Regulatory verification date: August 14, 2026
Review rule: Open this file only after completing the selected remediation section closed book. Review every missed question and every correct answer that was guessed or uncertain.

How to Use This File

1. Complete the applicable section of 10.13 - Optional Remediation Examination.md before opening this answer file.
2. Score only the remediation section or sections actually attempted.
3. Review every missed, guessed, or low-confidence question.
4. For each error, identify the controlling condition, not only the correct answer letter.
5. Enter unresolved errors in 10.10 - Error Analysis and Remediation.md.
6. A remediation topic is closed only after you can explain the rule or physical reason without notes and answer a fresh question on the same concept correctly.

Important: The remediation examination is not a third Universal mock examination and does not replace the two independent 100-question mock attempts.

Compact Answer Key

Core — Questions 1–12

Type I — Questions 13–24

Type II — Questions 25–37

Type III — Questions 38–50

Core Answers — Questions 1–12

Question 1

Correct answer: D. Zero ODP does not by itself create an exemption from the venting prohibition.

ODP describes ozone-depletion potential. Whether a refrigerant may be intentionally released depends on the venting rule and any specific exemption, not simply on whether ODP is zero.

• A is incorrect: GWP does not determine whether intentional venting is permitted.
• B is incorrect: HFCs do not contain chlorine; their zero ODP is one reason they do not deplete stratospheric ozone.
• C is incorrect: ODP is an environmental index, not a pressure measurement.
• D is correct: ODP describes ozone-depletion potential. Whether a refrigerant may be intentionally released depends on the venting rule and any specific exemption, not simply on whether ODP is zero.

Topic: Venting prohibition and ODP
EPA 608 section: Core
Error category: REG
Recommended review: 2.5 - Venting Prohibition.md
Regulatory / exam-value basis: Current EPA venting prohibition

Question 2

Correct answer: A. Both contain chlorine, but HCFCs generally have lower ODP than CFCs.

Both CFCs and HCFCs contain chlorine. HCFCs generally have lower ODP than CFCs because more of an HCFC can be destroyed in the lower atmosphere before reaching the stratosphere.

• A is correct: Both CFCs and HCFCs contain chlorine. HCFCs generally have lower ODP than CFCs because more of an HCFC can be destroyed in the lower atmosphere before reaching the stratosphere.
• B is incorrect: Both families contain chlorine.
• C is incorrect: HCFCs have nonzero ODP.
• D is incorrect: CFC means chlorofluorocarbon, so carbon is part of the family name and molecular composition.

Topic: CFC and HCFC composition / ODP
EPA 608 section: Core
Error category: DEF
Recommended review: 2.3 - Refrigerant Families ODP and GWP.md

Question 3

Correct answer: D. Recycling

Filtering or otherwise cleaning recovered refrigerant for permitted reuse is recycling. Reclamation is a higher-level process that restores refrigerant to the applicable purity specification and verifies that purity.

• A is incorrect: The question states that the refrigerant has not been processed to the full reclamation specification.
• B is incorrect: Dehydration refers to removing moisture from an appliance or system, not the Three-R classification of cleaned recovered refrigerant.
• C is incorrect: The refrigerant is captured and reused, not knowingly released to the atmosphere.
• D is correct: Filtering or otherwise cleaning recovered refrigerant for permitted reuse is recycling. Reclamation is a higher-level process that restores refrigerant to the applicable purity specification and verifies that purity.

Topic: Recover, recycle, reclaim
EPA 608 section: Core
Error category: DEF
Recommended review: 5.1 - Recover Recycle and Reclaim.md

Question 4

Correct answer: C. It can remove refrigerant without assistance from appliance components.

Self-contained recovery equipment has its own means to remove refrigerant and does not require the appliance compressor or other appliance components to provide the pumping action.

• A is incorrect: Self-contained equipment has an independent pumping means; having no pumping means describes the opposite idea.
• B is incorrect: Depending on the appliance compressor is characteristic of system-dependent recovery, not self-contained recovery.
• C is correct: Self-contained recovery equipment has its own means to remove refrigerant and does not require the appliance compressor or other appliance components to provide the pumping action.
• D is incorrect: Recovered refrigerant belongs in an appropriate refillable recovery cylinder, not a disposable cylinder.

Topic: Self-contained recovery equipment
EPA 608 section: Core
Error category: DEF
Recommended review: 5.2 - Recovery Equipment Categories.md

Question 5

Correct answer: B. Use a shorter, larger-diameter hose where appropriate.

Shorter, larger-diameter hoses generally reduce flow resistance and can increase recovery rate when the equipment and connections permit.

• A is incorrect: Longer, smaller-diameter hoses increase pressure drop and slow recovery.
• B is correct: Shorter, larger-diameter hoses generally reduce flow resistance and can increase recovery rate when the equipment and connections permit.
• C is incorrect: Unnecessary fittings add restrictions and increase pressure drop.
• D is incorrect: A recovery cylinder must never be heated with a torch or open flame.

Topic: Recovery speed
EPA 608 section: Core
Error category: PRO
Recommended review: 5.5 - Recovery Methods and Recovery Speed.md

Question 6

Correct answer: A. Nitrogen is an inert test gas when properly regulated; oxygen can create severe reaction/fire hazards.

Dry nitrogen is chemically stable for pressure testing when used with a regulator and relief protection. Oxygen can react violently with refrigerant oil and other materials and creates a serious fire or explosion hazard.

• A is correct: Dry nitrogen is chemically stable for pressure testing when used with a regulator and relief protection. Oxygen can react violently with refrigerant oil and other materials and creates a serious fire or explosion hazard.
• B is incorrect: Nitrogen pressurizes the system; a separate leak-locating method is still needed.
• C is incorrect: Oxygen can be pressurized; that is part of why its misuse is dangerous.
• D is incorrect: Nitrogen must be pressure-regulated and downstream relief protection is required.

Topic: Nitrogen pressure-test safety
EPA 608 section: Core
Error category: SAF
Recommended review: 6.5 - Nitrogen Pressure Testing.md

Question 7

Correct answer: D. It must not be refilled.

A disposable refrigerant cylinder is a one-way container and must not be refilled.

• A is incorrect: The 80% fill concept does not make a disposable cylinder refillable.
• B is incorrect: Repainting does not change the cylinder’s design, approval, or intended use.
• C is incorrect: Recovered refrigerant must be placed in a suitable refillable recovery cylinder; mixed refrigerants do not create an exception.
• D is correct: A disposable refrigerant cylinder is a one-way container and must not be refilled.

Topic: Disposable versus recovery cylinders
EPA 608 section: Core
Error category: SAF
Recommended review: 5.6 - Recovery Cylinders.md

Question 8

Correct answer: C. Absolute pressure is measured from perfect vacuum.

Absolute pressure uses perfect vacuum as its zero reference. Gauge pressure uses atmospheric pressure as its reference.

• A is incorrect: Gauge and absolute pressure have different zero references.
• B is incorrect: At standard atmospheric conditions, 0 psig is approximately 14.7 psia, not 0 psia.
• C is correct: Absolute pressure uses perfect vacuum as its zero reference. Gauge pressure uses atmospheric pressure as its reference.
• D is incorrect: Absolute pressure cannot be below zero because zero absolute is perfect vacuum.

Topic: Gauge versus absolute pressure
EPA 608 section: Core
Error category: CAL
Recommended review: 4.6 - Gauge Pressure Absolute Pressure and Vacuum.md

Question 9

Correct answer: A. Withdraw the blend from the source as liquid when required by the refrigerant procedure.

With a zeotropic blend, removing refrigerant from the source cylinder as liquid when required helps preserve the intended blend composition and reduce fractionation.

• A is correct: With a zeotropic blend, removing refrigerant from the source cylinder as liquid when required helps preserve the intended blend composition and reduce fractionation.
• B is incorrect: Removing only vapor can change blend composition because components may vaporize at different rates.
• C is incorrect: Air is a noncondensable contaminant and must not be intentionally added.
• D is incorrect: Mixing different refrigerants creates contamination and an unknown refrigerant mixture.

Topic: Zeotropic blend charging
EPA 608 section: Core
Error category: PRO
Recommended review: 3.2 - Pure Refrigerants and Refrigerant Blends.md

Question 10

Correct answer: C. To remove air and moisture before charging.

After recovery and repair, evacuation removes air and moisture from the opened refrigerant circuit before charging.

• A is incorrect: Evacuation does not change a refrigerant’s ODP.
• B is incorrect: Reclamation is a refrigerant-processing activity; evacuation is not reclamation.
• C is correct: After recovery and repair, evacuation removes air and moisture from the opened refrigerant circuit before charging.
• D is incorrect: Evacuation does not replace leak testing; each procedure has a different purpose.

Topic: Evacuation and dehydration
EPA 608 section: Core
Error category: PRO
Recommended review: 5.7 - Evacuation and Dehydration.md

Question 11

Correct answer: B. Connecting service hoses to a stationary appliance refrigerant circuit

Connecting service hoses to a stationary appliance refrigerant circuit can release refrigerant and is a technician activity that generally requires Section 608 certification.

• A is incorrect: Painting an external cabinet normally does not affect the refrigerant circuit.
• B is correct: Connecting service hoses to a stationary appliance refrigerant circuit can release refrigerant and is a technician activity that generally requires Section 608 certification.
• C is incorrect: Replacing a room thermostat without disturbing the refrigerant circuit normally does not create a refrigerant-release risk.
• D is incorrect: Cleaning an exterior nameplate does not normally affect the refrigerant circuit.

Topic: Technician certification activities
EPA 608 section: Core
Error category: REG
Recommended review: 1.2 - Who Must Be Certified.md
Regulatory / exam-value basis: Current Section 608 technician-certification requirement

Question 12

Correct answer: B. The applicable technician disposal records are kept for three years.

A 30-lb full-charge appliance falls within the current disposal-record range of more than 5 lb and less than 50 lb. The technician must ensure the required records are kept for three years.

• A is incorrect: The current disposal-record provision specifically covers appliances in the more-than-5-and-less-than-50-lb range.
• B is correct: A 30-lb full-charge appliance falls within the current disposal-record range of more than 5 lb and less than 50 lb. The technician must ensure the required records are kept for three years.
• C is incorrect: The rule requires records containing specified information; a verbal record is not sufficient.
• D is incorrect: The required records must be retained for three years.

Topic: Disposal recordkeeping for appliances above 5 lb and below 50 lb
EPA 608 section: Core
Error category: REG
Recommended review: 6.9 - Safe Disposal Requirements.md
Regulatory / exam-value basis: 40 CFR § 82.156(a)(3)

Type I Answers — Questions 13–24

Question 13

Correct answer: D. It contains 4 lb of refrigerant.

A 4-lb charge by itself is not enough. A small appliance must also be fully manufactured, charged, and hermetically sealed at the factory.

• A is incorrect: A qualifying factory-sealed room air conditioner with no more than 5 lb is a recognized small-appliance example.
• B is incorrect: This choice states all four required small-appliance conditions.
• C is incorrect: A qualifying factory-sealed household refrigerator is a standard small-appliance example.
• D is correct: A 4-lb charge by itself is not enough. A small appliance must also be fully manufactured, charged, and hermetically sealed at the factory.

Topic: Small-appliance definition
EPA 608 section: Type I
Error category: CLS
Recommended review: 7.1 - Small Appliance Definition and Examples.md
Regulatory / exam-value basis: Current Section 608 small-appliance definition

Question 14

Correct answer: B. 90%

With recovery equipment manufactured on or after November 15, 1993 and a functioning appliance compressor, the percentage method requires 90% recovery.

• A is incorrect: 80% applies to pre-November 15, 1993 recovery equipment or to post-1993 equipment when the appliance compressor is not functioning.
• B is correct: With recovery equipment manufactured on or after November 15, 1993 and a functioning appliance compressor, the percentage method requires 90% recovery.
• C is incorrect: 4% is not a Type I recovery requirement; 4 inches Hg vacuum is a separate alternative endpoint.
• D is incorrect: The federal percentage requirement is not 100%.

Topic: Type I recovery percentage — functional compressor
EPA 608 section: Type I
Error category: REG
Recommended review: 7.3 - Type I Recovery Requirements.md
Regulatory / exam-value basis: 40 CFR § 82.156(b)(2)

Question 15

Correct answer: C. 80%

When recovery equipment was manufactured before November 15, 1993, the Type I percentage requirement is 80%.

• A is incorrect: 50% is not the applicable Type I recovery percentage.
• B is incorrect: 70% is not the applicable Type I recovery percentage.
• C is correct: When recovery equipment was manufactured before November 15, 1993, the Type I percentage requirement is 80%.
• D is incorrect: 90% applies to post-1993 recovery equipment when the appliance compressor is functioning.

Topic: Type I recovery percentage — pre-1993 equipment
EPA 608 section: Type I
Error category: REG
Recommended review: 7.3 - Type I Recovery Requirements.md
Regulatory / exam-value basis: 40 CFR § 82.156(b)(1)

Question 16

Correct answer: D. 4 in. Hg vacuum

Instead of using the percentage method, the small appliance may be evacuated to 4 inches of mercury vacuum.

• A is incorrect: 0 psig is used in certain service-practice provisions for other appliance situations, not as the Type I alternative endpoint.
• B is incorrect: 25 mm Hg absolute is the normal Table 1 low-pressure-appliance endpoint.
• C is incorrect: 10 in. Hg vacuum is a Table 1 value for certain medium/high-pressure conditions, not the Type I alternative.
• D is correct: Instead of using the percentage method, the small appliance may be evacuated to 4 inches of mercury vacuum.

Topic: Type I alternative endpoint
EPA 608 section: Type I
Error category: REG
Recommended review: 7.3 - Type I Recovery Requirements.md
Regulatory / exam-value basis: 40 CFR § 82.156(b)(3)

Question 17

Correct answer: D. Provide access to both high and low sides.

With an inoperative compressor and a capillary-tube restriction, using both high- and low-side access helps remove refrigerant that could otherwise remain trapped on one side.

• A is incorrect: The cabinet drain is not a refrigerant-circuit recovery connection.
• B is incorrect: Thermostat wiring provides no refrigerant access.
• C is incorrect: Opening the refrigerant circuit to atmosphere would intentionally release refrigerant and is not an acceptable recovery method.
• D is correct: With an inoperative compressor and a capillary-tube restriction, using both high- and low-side access helps remove refrigerant that could otherwise remain trapped on one side.

Topic: Failed-compressor Type I recovery access
EPA 608 section: Type I
Error category: PRO
Recommended review: 7.6 - Recovery with a Failed Compressor.md

Question 18

Correct answer: B. It raises refrigerant vapor pressure and helps trapped liquid evaporate.

Controlled warming increases refrigerant vapor pressure and encourages trapped liquid refrigerant to evaporate, helping it move toward the recovery connection.

• A is incorrect: Warming does not change the appliance’s certification classification.
• B is correct: Controlled warming increases refrigerant vapor pressure and encourages trapped liquid refrigerant to evaporate, helping it move toward the recovery connection.
• C is incorrect: Heating does not change a disposable cylinder into a refillable recovery cylinder.
• D is incorrect: Applicable recovery-equipment requirements still apply.

Topic: Controlled warming during Type I recovery
EPA 608 section: Type I
Error category: PRO
Recommended review: 7.6 - Recovery with a Failed Compressor.md

Question 19

Correct answer: A. Remove it and restore/reseal the tubing, then leak check.

The Type I test-topic emphasis taught in this course is to remove the temporary solderless access fitting after service, restore or reseal the tubing, and leak check the repair.

• A is correct: The Type I test-topic emphasis taught in this course is to remove the temporary solderless access fitting after service, restore or reseal the tubing, and leak check the repair.
• B is incorrect: A temporary piercing fitting is not the preferred permanent final seal.
• C is incorrect: Opening it to atmosphere would release refrigerant.
• D is incorrect: An access fitting is not a pressure-relief device.

Topic: Temporary solderless access fitting
EPA 608 section: Type I
Error category: PRO
Recommended review: 7.4 - Access Fittings and Process Stubs.md

Question 20

Correct answer: A. It is a length of tubing used for refrigerant access and can be resealed.

A process stub is a short length of tubing provided for refrigerant access and can be resealed after service.

• A is correct: A process stub is a short length of tubing provided for refrigerant access and can be resealed after service.
• B is incorrect: A recovery cylinder is a separate refrigerant storage container.
• C is incorrect: An oxygen regulator is unrelated to a process stub, and oxygen must not be used for refrigerant-system pressure testing.
• D is incorrect: A purge unit is a low-pressure-chiller component used to remove noncondensables.

Topic: Process stub
EPA 608 section: Type I
Error category: DEF
Recommended review: 7.4 - Access Fittings and Process Stubs.md

Question 21

Correct answer: A. Self-contained recovery equipment

Self-contained recovery equipment has its own recovery compressor or pumping means, so it does not depend on the failed appliance compressor.

• A is correct: Self-contained recovery equipment has its own recovery compressor or pumping means, so it does not depend on the failed appliance compressor.
• B is incorrect: A process stub only provides access; it does not pump refrigerant.
• C is incorrect: A thermostat controls operation but cannot recover refrigerant.
• D is incorrect: A sight glass is an observation component and does not provide recovery pumping.

Topic: Self-contained recovery with failed compressor
EPA 608 section: Type I
Error category: PRO
Recommended review: 7.7 - Self-Contained Recovery.md

Question 22

Correct answer: B. R-134a as a common replacement refrigerant associated with many former R-12 small-appliance applications

R-134a became a common non-ODS refrigerant associated with many small-appliance applications that historically used R-12. This is an application association, not a statement that every R-12 appliance can be retrofitted without manufacturer or engineering evaluation.

• A is incorrect: R-22 is not the only refrigerant allowed in refrigerators and was not the universal replacement for R-12 household refrigeration.
• B is correct: R-134a became a common non-ODS refrigerant associated with many small-appliance applications that historically used R-12. This is an application association, not a statement that every R-12 appliance can be retrofitted without manufacturer or engineering evaluation.
• C is incorrect: R-11 is historically associated with low-pressure applications, not a high-pressure small-appliance standard.
• D is incorrect: R-410A is an HFC blend and contains no chlorine; it is not a CFC.

Topic: Common small-appliance refrigerant association
EPA 608 section: Type I
Error category: REC
Recommended review: 7.2 - Type I Exclusions and Boundary Cases.md

Question 23

Correct answer: C. High heat can create hazardous decomposition products.

Exposure of refrigerant to very high temperatures or flame can produce hazardous decomposition products, so refrigerant should not contact a torch flame.

• A is incorrect: Brazing on a refrigerant circuit requires proper refrigerant recovery and safe preparation first.
• B is incorrect: Torch heat does not improve refrigerant reclamation purity.
• C is correct: Exposure of refrigerant to very high temperatures or flame can produce hazardous decomposition products, so refrigerant should not contact a torch flame.
• D is incorrect: PPE requirements are not eliminated by using heat.

Topic: Refrigerant decomposition hazard
EPA 608 section: Type I
Error category: SAF
Recommended review: 6.3 - Fire Explosion and Decomposition Hazards.md

Question 24

Correct answer: C. A sticker that only says “empty”

A sticker that merely says “empty” does not by itself satisfy the prior-recovery verification requirements. Acceptable pathways include recovery by the final processor or qualifying prior-recovery documentation or contract procedures.

• A is incorrect: A properly completed signed statement can be an acceptable prior-recovery verification method.
• B is incorrect: A qualifying contract with a regular supplier can be used where the safe-disposal rule permits that pathway.
• C is correct: A sticker that merely says “empty” does not by itself satisfy the prior-recovery verification requirements. Acceptable pathways include recovery by the final processor or qualifying prior-recovery documentation or contract procedures.
• D is incorrect: The final processor may recover the refrigerant directly instead of relying on prior recovery.

Topic: Small-appliance disposal verification
EPA 608 section: Type I
Error category: REG
Recommended review: 7.8 - Type I Service and Disposal Scenarios.md
Regulatory / exam-value basis: Current Section 608 safe-disposal requirements

Type II Answers — Questions 25–37

Question 25

Correct answer: A. Medium

160 psia at 104°F lies within the current medium-pressure range of 45 to 170 psia.

• A is correct: 160 psia at 104°F lies within the current medium-pressure range of 45 to 170 psia.
• B is incorrect: Low pressure is below 45 psia at 104°F.
• C is incorrect: High pressure begins at 170 psia at 104°F under the course’s current classification table.
• D is incorrect: Very-high pressure requires the applicable >355-psia or critical-temperature criterion.

Topic: Medium-pressure classification
EPA 608 section: Type II
Error category: CLS
Recommended review: 8.2 - Refrigerant Pressure Classifications.md
Regulatory / exam-value basis: Current Section 608 pressure definitions

Question 26

Correct answer: B. A field-connected R-410A residential split system

A field-connected R-410A residential split system is a typical Type II appliance because it is not a factory-sealed small appliance and falls within the pressure categories covered by Type II.

• A is incorrect: A qualifying factory-sealed refrigerator with 1 lb of refrigerant is Type I.
• B is correct: A field-connected R-410A residential split system is a typical Type II appliance because it is not a factory-sealed small appliance and falls within the pressure categories covered by Type II.
• C is incorrect: A low-pressure R-123 centrifugal chiller is Type III.
• D is incorrect: A passenger-car MVAC serviced for consideration is handled under Section 609, not ordinary Type II certification.

Topic: Type II appliance classification
EPA 608 section: Type II
Error category: CLS
Recommended review: 8.1 - Type II Equipment and Scope.md

Question 27

Correct answer: A. Oil residue near a refrigerant joint

Oil residue near a joint is a useful clue that refrigerant and oil may have escaped, but it does not by itself prove the exact location of an active refrigerant leak.

• A is correct: Oil residue near a joint is a useful clue that refrigerant and oil may have escaped, but it does not by itself prove the exact location of an active refrigerant leak.
• B is incorrect: A bubble forming at a specific joint during an appropriate test directly identifies a leak location.
• C is incorrect: A repeatable detector response localized at a fitting is a leak-locating method, although proper confirmation and detector use still matter.
• D is incorrect: A known leaking service valve is already a located leak rather than merely a general indicator.

Topic: Leak indication versus leak location
EPA 608 section: Type II
Error category: DIST
Recommended review: 8.4 - Leak Indicators and Leak Detection.md

Question 28

Correct answer: A. Dry nitrogen with proper regulator and relief protection

After recovery, dry nitrogen used with a proper regulator and downstream relief protection is the appropriate gas for controlled pressure leak testing.

• A is correct: After recovery, dry nitrogen used with a proper regulator and downstream relief protection is the appropriate gas for controlled pressure leak testing.
• B is incorrect: Oxygen can react dangerously with refrigerant oil and other materials.
• C is incorrect: Compressed air introduces oxygen and moisture and is not the proper Section 608 test gas.
• D is incorrect: Intentionally combining refrigerant and oxygen creates a dangerous condition.

Topic: Nitrogen leak testing
EPA 608 section: Type II
Error category: SAF
Recommended review: 8.4 - Leak Indicators and Leak Detection.md

Question 29

Correct answer: D. Industrial process refrigeration

Industrial process refrigeration has a current Section 608 ODS trigger leak rate of 30% over a 12-month period.

• A is incorrect: Comfort cooling uses a 10% trigger.
• B is incorrect: Commercial refrigeration uses a 20% trigger.
• C is incorrect: The all-other-appliances category uses a 10% trigger.
• D is correct: Industrial process refrigeration has a current Section 608 ODS trigger leak rate of 30% over a 12-month period.

Topic: Current ODS leak-rate trigger — industrial process refrigeration
EPA 608 section: Type II
Error category: REG
Recommended review: 8.5 - Leak Repair Requirements and Current Regulatory Updates.md
Regulatory / exam-value basis: 40 CFR § 82.157 / current EPA leak-repair table

Question 30

Correct answer: B. 50 lb

The current Section 608 leak-repair provisions apply to qualifying appliances with a full charge of 50 lb or more of ozone-depleting refrigerant.

• A is incorrect: 5 lb is associated with the small-appliance charge limit, not the § 82.157 leak-repair threshold.
• B is correct: The current Section 608 leak-repair provisions apply to qualifying appliances with a full charge of 50 lb or more of ozone-depleting refrigerant.
• C is incorrect: 15 lb controls the ordinary system-dependent recovery-equipment restriction.
• D is incorrect: 200 lb is a boundary in Table 1 evacuation requirements.

Topic: Section 608 ODS leak-repair applicability threshold
EPA 608 section: Type II
Error category: REG
Recommended review: 8.5 - Leak Repair Requirements and Current Regulatory Updates.md
Regulatory / exam-value basis: 40 CFR § 82.157 / current EPA leak-repair requirements

Question 31

Correct answer: B. 15 lb full charge

System-dependent recovery equipment may not be used on an appliance with a full charge of more than 15 lb unless the equipment is permanently attached as a pump-out unit.

• A is incorrect: 50 lb is associated with current Section 608 ODS leak-repair applicability.
• B is correct: System-dependent recovery equipment may not be used on an appliance with a full charge of more than 15 lb unless the equipment is permanently attached as a pump-out unit.
• C is incorrect: 200 lb changes several Table 1 evacuation rows.
• D is incorrect: 355 is a pressure-classification value in psia, not a refrigerant-charge limit in pounds.

Topic: System-dependent recovery-equipment restriction
EPA 608 section: Type II
Error category: REG
Recommended review: 8.7 - Type II Recovery Procedures.md
Regulatory / exam-value basis: 40 CFR § 82.156(e)

Question 32

Correct answer: D. 10 in. Hg vacuum

With post-November 15, 1993 recovery equipment, a medium-pressure appliance with a full charge under 200 lb must be evacuated to 10 in. Hg vacuum.

• A is incorrect: 0 in. Hg applies to very-high-pressure appliances and to high-pressure appliances under 200 lb, not this medium-pressure case.
• B is incorrect: 4 in. Hg is the pre-1993 medium-pressure value.
• C is incorrect: 15 in. Hg applies to post-1993 medium-pressure appliances with a full charge of 200 lb or more.
• D is correct: With post-November 15, 1993 recovery equipment, a medium-pressure appliance with a full charge under 200 lb must be evacuated to 10 in. Hg vacuum.

Topic: Type II Table 1 — medium pressure under 200 lb
EPA 608 section: Type II
Error category: REG
Recommended review: 8.8 - Type II Evacuation Requirements.md
Regulatory / exam-value basis: 40 CFR § 82.156 Table 1

Question 33

Correct answer: D. 15 in. Hg vacuum

With post-November 15, 1993 recovery equipment, a medium-pressure appliance with a 250-lb full charge is in the 200-lb-or-more row and requires 15 in. Hg vacuum.

• A is incorrect: 0 in. Hg does not apply to this medium-pressure/post-1993 condition.
• B is incorrect: 4 in. Hg is the pre-1993 medium-pressure value.
• C is incorrect: 10 in. Hg is the post-1993 medium-pressure value for full charges under 200 lb.
• D is correct: With post-November 15, 1993 recovery equipment, a medium-pressure appliance with a 250-lb full charge is in the 200-lb-or-more row and requires 15 in. Hg vacuum.

Topic: Type II Table 1 — medium pressure 200 lb or more
EPA 608 section: Type II
Error category: REG
Recommended review: 8.8 - Type II Evacuation Requirements.md
Regulatory / exam-value basis: 40 CFR § 82.156 Table 1

Question 34

Correct answer: C. Replacing a compressor

Removal of a compressor is explicitly included in the definition of major maintenance, service, or repair.

• A is incorrect: Replacing external insulation does not remove one of the listed major refrigerant-circuit components.
• B is incorrect: Replacing a service cap is not one of the named major-component removals.
• C is correct: Removal of a compressor is explicitly included in the definition of major maintenance, service, or repair.
• D is incorrect: Cleaning a condenser coil without opening the refrigerant circuit is not major repair by component removal.

Topic: Major maintenance, service, or repair
EPA 608 section: Type II
Error category: REG
Recommended review: 8.9 - Major Repair Special Conditions and Compressor Service.md
Regulatory / exam-value basis: 40 CFR § 82.152 definition of major maintenance, service, or repair

Question 35

Correct answer: C. No higher than 0 psig

For a qualifying non-major repair when no evacuation to the atmosphere will follow, a medium-, high-, or very-high-pressure appliance must be evacuated to no higher than 0 psig before opening.

• A is incorrect: 10 psig is not the pressure ceiling for this provision.
• B is incorrect: 5 psig belongs to the special oil-change provision.
• C is correct: For a qualifying non-major repair when no evacuation to the atmosphere will follow, a medium-, high-, or very-high-pressure appliance must be evacuated to no higher than 0 psig before opening.
• D is incorrect: 25 psig is not permitted by this opening provision.

Topic: Qualifying non-major opening provision
EPA 608 section: Type II
Error category: REG
Recommended review: 8.9 - Major Repair Special Conditions and Compressor Service.md
Regulatory / exam-value basis: 40 CFR § 82.156(a)(1)(i)

Question 36

Correct answer: A. Isolate leaking from non-leaking portions and apply the required levels separately.

When leaks make the normal Table 1 endpoint unattainable or would substantially contaminate recovered refrigerant, leaking and non-leaking components must be isolated where possible. Non-leaking components go to Table 1; leaking components go to the lowest attainable level without substantial contamination, not above 0 psig.

• A is correct: When leaks make the normal Table 1 endpoint unattainable or would substantially contaminate recovered refrigerant, leaking and non-leaking components must be isolated where possible. Non-leaking components go to Table 1; leaking components go to the lowest attainable level without substantial contamination, not above 0 psig.
• B is incorrect: A leak does not create permission to vent the charge.
• C is incorrect: Oxygen must not be added to a refrigerant system.
• D is incorrect: The rule provides a controlled exception, not a blanket exemption for every component.

Topic: Leaking-appliance evacuation exception
EPA 608 section: Type II
Error category: REG
Recommended review: 8.9 - Major Repair Special Conditions and Compressor Service.md
Regulatory / exam-value basis: 40 CFR § 82.156(a)(2)

Question 37

Correct answer: C. Start the compressor with its discharge service valve closed.

Starting a positive-displacement reciprocating compressor with the discharge service valve closed can rapidly create dangerous discharge pressure and must be avoided.

• A is incorrect: Verifying an open discharge flow path is a safe pre-start check.
• B is incorrect: High-pressure safety controls should remain functional.
• C is correct: Starting a positive-displacement reciprocating compressor with the discharge service valve closed can rapidly create dangerous discharge pressure and must be avoided.
• D is incorrect: Abnormal head pressure should be diagnosed and corrected rather than bypassed.

Topic: Reciprocating-compressor discharge safety
EPA 608 section: Type II
Error category: SAF
Recommended review: 8.10 - Type II Safety.md

Type III Answers — Questions 38–50

Question 38

Correct answer: C. The refrigerant side can operate below atmospheric pressure.

Because the refrigerant side of many low-pressure chillers operates below atmospheric pressure, air and moisture can be drawn inward through leaks.

• A is incorrect: A Type III chiller is a closed refrigerant system, not intentionally open to atmosphere.
• B is incorrect: Low-pressure refrigerants are defined by low saturation pressure, not operation above 500 psig.
• C is correct: Because the refrigerant side of many low-pressure chillers operates below atmospheric pressure, air and moisture can be drawn inward through leaks.
• D is incorrect: A purge unit removes noncondensables; it is not intended to pump air into the machine.

Topic: Low-pressure appliance inward leakage
EPA 608 section: Type III
Error category: DEF
Recommended review: 9.1 - Low-Pressure Appliance Fundamentals.md

Question 39

Correct answer: A. Noncondensable gases while minimizing refrigerant loss

A purge unit removes air and other noncondensable gases that enter a low-pressure system while minimizing refrigerant loss.

• A is correct: A purge unit removes air and other noncondensable gases that enter a low-pressure system while minimizing refrigerant loss.
• B is incorrect: Full-system refrigerant recovery is performed with recovery equipment, not the purge unit.
• C is incorrect: The purge unit does not remove chilled water from the evaporator.
• D is incorrect: Compressor bearings are mechanical components and are not removed by a purge unit.

Topic: Purge-unit purpose
EPA 608 section: Type III
Error category: DEF
Recommended review: 9.3 - Air Moisture and Purge Units.md

Question 40

Correct answer: A. 10 psig

For this project’s Type III examination preparation, 10 psig is the maximum leak-test pressure associated with a low-pressure centrifugal chiller. It is a maximum, not a target that must always be reached.

• A is correct: For this project’s Type III examination preparation, 10 psig is the maximum leak-test pressure associated with a low-pressure centrifugal chiller. It is a maximum, not a target that must always be reached.
• B is incorrect: 5 psig is the current special oil-change pressure provision, not the course’s Type III leak-test maximum.
• C is incorrect: 0 psig is atmospheric gauge pressure and is used in specific opening provisions, not the traditional leak-test maximum.
• D is incorrect: 25 psig exceeds the Type III exam-preparation maximum.

Topic: Low-pressure chiller leak-test maximum
EPA 608 section: Type III
Error category: REG
Recommended review: 9.4 - Low-Pressure Leak Detection and Pressurization.md
Regulatory / exam-value basis: EPA Test Topics identify the maximum leak-test-pressure concept; 10 psig is the established project exam-preparation value

Question 41

Correct answer: B. 10 psig

The traditional Type III examination value associated with the high-pressure cutout on recovery equipment used with low-pressure appliances is 10 psig.

• A is incorrect: 5 psig is associated with the current special oil-change provision.
• B is correct: The traditional Type III examination value associated with the high-pressure cutout on recovery equipment used with low-pressure appliances is 10 psig.
• C is incorrect: 15 psig is the traditional exam value associated with the low-pressure recovery-vessel rupture disc.
• D is incorrect: 25 psig is not the traditional recovery-unit cutout value used in this course.

Topic: Low-pressure recovery-unit high-pressure cutout
EPA 608 section: Type III
Error category: REC
Recommended review: 9.5 - Type III Recovery Sequence.md
Regulatory / exam-value basis: Traditional Type III exam-preparation value; EPA Test Topics identify the high-pressure-cutout concept

Question 42

Correct answer: A. 15 psig

The traditional Type III examination value associated with the rupture disc on a low-pressure recovery vessel is 15 psig.

• A is correct: The traditional Type III examination value associated with the rupture disc on a low-pressure recovery vessel is 15 psig.
• B is incorrect: 10 psig is associated with the traditional recovery-unit high-pressure cutout and the separate leak-test maximum concept.
• C is incorrect: 4 psig is not the recovery-vessel rupture-disc exam value.
• D is incorrect: 25 psig is not the recovery-vessel rupture-disc exam value.

Topic: Low-pressure recovery-vessel rupture disc
EPA 608 section: Type III
Error category: REC
Recommended review: 9.10 - Type III Safety and Machinery Rooms.md
Regulatory / exam-value basis: Traditional Type III exam-preparation value; do not generalize it to every chiller relief device

Question 43

Correct answer: D. Liquid first, then vapor

When accessible bulk liquid is present, recovering liquid first removes refrigerant mass quickly. Vapor recovery then removes the remaining refrigerant.

• A is incorrect: Beginning with vapor while accessible bulk liquid remains is generally slower.
• B is incorrect: Air should not be deliberately introduced into the refrigerant circuit.
• C is incorrect: Oil and nitrogen are not the primary refrigerant-recovery sequence.
• D is correct: When accessible bulk liquid is present, recovering liquid first removes refrigerant mass quickly. Vapor recovery then removes the remaining refrigerant.

Topic: Type III recovery sequence
EPA 608 section: Type III
Error category: PRO
Recommended review: 9.5 - Type III Recovery Sequence.md

Question 44

Correct answer: C. To reduce the risk that water in the tubes freezes as refrigerant saturation temperature falls.

As refrigerant pressure falls, saturation temperature falls. Water remaining in heat-exchanger tubes can freeze and damage tubes, so water must be circulated or otherwise managed according to the recovery procedure.

• A is incorrect: Water management does not replace the purge unit’s noncondensable-removal function.
• B is incorrect: Water circulation does not affect refrigerant ODP.
• C is correct: As refrigerant pressure falls, saturation temperature falls. Water remaining in heat-exchanger tubes can freeze and damage tubes, so water must be circulated or otherwise managed according to the recovery procedure.
• D is incorrect: The purpose is freeze prevention, not increasing recovery-cylinder fill.

Topic: Freeze prevention during low-pressure recovery
EPA 608 section: Type III
Error category: SAF
Recommended review: 9.6 - Freeze Prevention During Recovery.md

Question 45

Correct answer: A. Drain the affected evaporator and condenser water sides before deep recovery.

Under the traditional Type III examination procedure taught in this course, suspected tube leakage calls for draining the affected evaporator and condenser water sides before deep recovery so water is not drawn into the refrigerant circuit and frozen.

• A is correct: Under the traditional Type III examination procedure taught in this course, suspected tube leakage calls for draining the affected evaporator and condenser water sides before deep recovery so water is not drawn into the refrigerant circuit and frozen.
• B is incorrect: Increasing water pressure while pulling a deep vacuum can worsen water intrusion through a leaking tube.
• C is incorrect: Oxygen is not an appropriate water-box or refrigerant-system test gas for this procedure.
• D is incorrect: The recovery-unit safety cutout must not be disabled.

Topic: Suspected tube leak before recovery
EPA 608 section: Type III
Error category: SAF
Recommended review: 9.6 - Freeze Prevention During Recovery.md

Question 46

Correct answer: D. Help drive dissolved refrigerant out of oil before removal.

Heating oil to the traditional 130°F exam value helps drive dissolved refrigerant out of the oil before the oil is removed, reducing refrigerant release.

• A is incorrect: Oil temperature does not determine the refrigerant pressure classification.
• B is incorrect: The purpose is not to raise water-box pressure.
• C is incorrect: The oil-heating step does not set a rupture-disc rating.
• D is correct: Heating oil to the traditional 130°F exam value helps drive dissolved refrigerant out of the oil before the oil is removed, reducing refrigerant release.

Topic: Refrigerant dissolved in oil
EPA 608 section: Type III
Error category: PRO
Recommended review: 9.7 - Refrigerant in Oil.md
Regulatory / exam-value basis: EPA Section 608 Test Topics explicitly identify the 130°F oil-heating value

Question 47

Correct answer: D. Refrigerant vapor

A deeply evacuated low-pressure chiller should receive refrigerant vapor first. Raising pressure raises the refrigerant saturation temperature and reduces the risk of freezing water in the tubes before liquid charging begins.

• A is incorrect: Bulk liquid introduced into a deep vacuum can flash rapidly and create severe cooling and freezing risk.
• B is incorrect: Oxygen must not be introduced into the refrigerant circuit.
• C is incorrect: Compressed air introduces moisture and noncondensables and is not the charging medium.
• D is correct: A deeply evacuated low-pressure chiller should receive refrigerant vapor first. Raising pressure raises the refrigerant saturation temperature and reduces the risk of freezing water in the tubes before liquid charging begins.

Topic: Vapor-first charging of low-pressure chillers
EPA 608 section: Type III
Error category: PRO
Recommended review: 9.8 - Recharging Low-Pressure Systems.md

Question 48

Correct answer: C. Evaporator charging valve

EPA Type III test topics identify the evaporator charging valve as the charging connection for centrifugal chillers.

• A is incorrect: The purge exhaust is not the normal refrigerant charging connection.
• B is incorrect: The water-box drain is on the water side, not the refrigerant charging circuit.
• C is correct: EPA Type III test topics identify the evaporator charging valve as the charging connection for centrifugal chillers.
• D is incorrect: The oil-pump discharge is not the designated chiller refrigerant charging connection.

Topic: Centrifugal-chiller charging connection
EPA 608 section: Type III
Error category: REC
Recommended review: 9.8 - Recharging Low-Pressure Systems.md
Regulatory / exam-value basis: EPA Section 608 Type III Test Topics

Question 49

Correct answer: B. 25 mm Hg absolute

The current Table 1 endpoint for a low-pressure appliance is 25 mm Hg absolute, for both pre- and post-November 15, 1993 recovery equipment.

• A is incorrect: 25 in. Hg vacuum is a different unit and is not the low-pressure Table 1 value.
• B is correct: The current Table 1 endpoint for a low-pressure appliance is 25 mm Hg absolute, for both pre- and post-November 15, 1993 recovery equipment.
• C is incorrect: 15 in. Hg vacuum applies to a post-1993 medium-pressure appliance with a full charge of 200 lb or more, not a low-pressure appliance.
• D is incorrect: The rule does not require exactly 0 psia; 25 mm Hg absolute is the specified endpoint.

Topic: Low-pressure Table 1 evacuation endpoint
EPA 608 section: Type III
Error category: REG
Recommended review: 9.9 - Type III Evacuation Requirements.md
Regulatory / exam-value basis: 40 CFR § 82.156 Table 1

Question 50

Correct answer: B. It measures refrigerant concentration and does not automatically replace an oxygen monitor.

A refrigerant monitor measures refrigerant concentration. An oxygen monitor measures oxygen concentration, so one instrument does not automatically replace the other.

• A is incorrect: A refrigerant monitor does not determine whether a space meets the regulatory definition of a confined space.
• B is correct: A refrigerant monitor measures refrigerant concentration. An oxygen monitor measures oxygen concentration, so one instrument does not automatically replace the other.
• C is incorrect: A refrigerant monitor is not a water-pressure instrument.
• D is incorrect: Monitoring does not permit required pressure-relief devices to be disabled.

Topic: Machinery-room refrigerant monitoring
EPA 608 section: Type III
Error category: SAF
Recommended review: 9.10 - Type III Safety and Machinery Rooms.md

Remediation Score Record

Remediation Closure Checklist

For every missed or guessed remediation question:

• I can state the correct answer without looking.
• I can explain why the correct answer is correct.
• I can explain why each distractor is wrong.
• I know which condition, unit, appliance type, date, or regulatory framework controls the answer.
• I reviewed the recommended instructional section.
• I entered any unresolved issue in the error log.
• I answered a fresh question on the same concept correctly.
• Any P1 safety or current-regulation error is fully closed before the official examination.

A high remediation score does not replace the project’s Universal readiness requirement:

Core ≥22/25
Type I ≥22/25
Type II ≥22/25
Type III ≥22/25

on two separate independent closed-book Universal mock attempts, with no unresolved P1 errors.

References

Current EPA and Regulatory Sources

1. U.S. Environmental Protection Agency, Section 608 Test Topics, reviewed August 14, 2026.

2. U.S. Environmental Protection Agency, Stationary Refrigeration Service Practice Requirements, reviewed August 14, 2026.

3. U.S. Environmental Protection Agency, Required Level of Evacuation of Appliances, reviewed August 14, 2026.

4. U.S. Environmental Protection Agency, Stationary Refrigeration Leak Repair Requirements, reviewed August 14, 2026.

5. U.S. Environmental Protection Agency, EPA’s Refrigerant Management Program: Questions and Answers for Section 608 Certified Technicians, reviewed August 14, 2026.

6. Electronic Code of Federal Regulations, 40 CFR § 82.152 — Definitions, reviewed August 14, 2026.

7. Electronic Code of Federal Regulations, 40 CFR § 82.156 — Proper Evacuation of Refrigerant from Appliances, reviewed August 14, 2026.

8. Electronic Code of Federal Regulations, 40 CFR § 82.157 — Appliance Maintenance and Leak Repair, reviewed August 14, 2026.

Module 10 Assessment Files

9. 10.10 - Error Analysis and Remediation

10. 10.13 - Optional Remediation Examination

11. 10.15 - Official Examination Readiness Checklist

12. 10.16 - Final Quick Reference