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Free EPA 608 Cram Sheet: Core, Type I, Type II & Type III

Reviewing for the EPA Section 608 technician certification exam? This free study guide organizes key concepts, regulatory requirements, and important numbers by exam section. Use the Core and specialty-type summaries to review what you know and identify topics to study further.

EPA 608 Core

EPA 608 Core Final Cram List

  1. Ozone (O₃) is concentrated in the stratosphere. CFCs can drift up there, where UV radiation breaks them apart and releases reactive chlorine.
  2. One chlorine atom can destroy approximately 100,000 ozone molecules.
  3. HFC refrigerants have an ODP of 0 (no chlorine) but may have high GWP. CFCs have the highest ozone depletion potential among refrigerant families.
  4. The Montreal Protocol (1987) is the international treaty that phased out ozone-depleting substances. The Clean Air Act Amendments of 1990 gave the EPA authority to regulate refrigerants under Section 608.
  5. Four EPA certification types exist: Type I (small appliances), Type II (high-pressure and very-high-pressure appliances), Type III (low-pressure appliances), and Universal (Types I, II, and III). Section 608 certification does not expire.
  6. A small appliance is factory-manufactured, factory-charged, hermetically sealed, and contains 5 pounds or less of refrigerant.
  7. Know the three R's:
    • Recover: Remove refrigerant and store it in an external container.
    • Recycle: Clean refrigerant for reuse by the same owner.
    • Reclaim: Process refrigerant to AHRI Standard 700 purity and verify that purity using the required analytical methods.
  8. Recovery equipment is either:
    • Self-contained (has its own compressor), or
    • System-dependent (requires assistance from components within the appliance).
  9. System-dependent equipment may not be used on appliances with a full charge greater than 15 pounds unless permanently attached as a pump-out unit.
  10. Never fill a recovery cylinder above 80% of its maximum allowable gross weight.
  11. Never mix refrigerants in the same recovery cylinder.
  12. Disposable cylinders must never be refilled and must be rendered unusable before disposal.
  13. Intentional venting of refrigerant is generally prohibited. Limited de minimis releases associated with good-faith recovery are allowed under EPA regulations.
  14. Recover refrigerant before opening a regulated appliance.
  15. Deep vacuum is measured in microns. Lower micron readings indicate a deeper vacuum.
  16. A micron gauge is much more accurate than a standard compound gauge when measuring deep vacuum.
  17. A dehydration vacuum of approximately 500 microns or lower is a common HVAC industry target, although EPA evacuation requirements vary by equipment type.
  18. Leak-repair requirements generally apply to appliances containing 50 pounds or more of refrigerant when the applicable regulatory trigger conditions are met.
  19. ASHRAE safety classifications:
    • Toxicity: A (lower), B (higher)
    • Flammability: 1 (no flame propagation), 2L (lower flammability, lower burning velocity), 2 (lower flammability), 3 (higher flammability)
  20. Refrigerant safety basics:
    • Flush eyes with water for at least 15 minutes after exposure.
    • Treat frostbite with lukewarm water; never rub affected skin or apply direct heat.
    • Refrigerants can displace oxygen, so provide adequate ventilation in confined spaces.
  21. Most Section 608 records must be retained for 3 years.
  22. A technician's certification documentation must be kept on file until 3 years after the technician stops operating.

EPA 608 Core Most-Tested Numbers

NumberMeaning
3 oxygen atomsMake one ozone (O₃) molecule.
100,000 ozone moleculesApproximate number that one chlorine atom can destroy.
5 poundsMaximum refrigerant charge for a small appliance.
15 poundsMaximum appliance charge for using system-dependent recovery equipment.
50 poundsRefrigerant charge at which leak-repair requirements generally begin when the applicable regulatory conditions are met.
80%Maximum allowed fill level for a refillable recovery cylinder.
3 yearsCommon EPA record-retention period.

EPA 608 Type I

EPA 608 Type I Final Cram List

  1. Type I scope and certification: Type I covers refrigerant handling during maintenance, service, or repair of small appliances. Universal certification also includes Type I authority. Type I does not cover motor vehicle air conditioners or low-pressure appliances. Field-assembled split systems do not meet the small-appliance definition. Section 608 technician certification has no fixed expiration date.
  2. Small-appliance definition: A small appliance must be fully manufactured, charged, and hermetically sealed at the factory and contain 5 pounds or less of refrigerant. Examples include household refrigerators, freezers, window air conditioners, dehumidifiers, drinking-water coolers, vending machines, and qualifying packaged terminal units.
  3. Venting and disposal: A small refrigerant charge does not permit intentional venting. Use low-loss fittings and recover regulated refrigerant. A person performing only disposal-related refrigerant removal does not need technician certification, but the recovery equipment must meet EPA performance requirements. The final disposer is responsible for verifying that refrigerant recovery was completed before final disposal.
  4. Equipment date: November 15, 1993 is the dividing date for small-appliance recovery-equipment requirements. Equipment made or imported on or after that date must be certified by an EPA-approved testing organization and carry the required label.
  5. Recovery requirements: With equipment made on or after November 15, 1993, recover 90% when the appliance compressor works and 80% when it does not. Reaching a 4-inch Hg vacuum is an alternative in either case. Equipment made before November 15, 1993 requires 80% recovery regardless of compressor condition, or the same 4-inch Hg vacuum.
  6. Recovery-equipment types: Self-contained equipment has its own means of removing refrigerant. System-dependent equipment relies on appliance pressure, the appliance compressor, or applied heat. System-dependent equipment may be used on appliances containing 15 pounds or less of refrigerant. Because a Type I small appliance contains no more than 5 pounds, every small appliance falls within this limit.
  7. Working compressor: During system-dependent recovery, operate a working appliance compressor to help move refrigerant toward the high side and the recovery connection.
  8. Failed compressor: When the compressor does not operate, access both the high and low sides so a capillary tube or other restriction does not trap refrigerant. Gently warm the compressor and tap it with a rubber mallet to help release refrigerant trapped in the oil. Never use an open flame.
  9. Vacuum-pump recovery: A dehydration vacuum pump may be used to evacuate a nonpressurized recovery container. Disconnect the pump before appliance pressure moves refrigerant into the container. Do not use the vacuum pump to force refrigerant into a pressurized recovery vessel.
  10. Process stub and temporary fittings: The process stub provides access to the refrigerant system and can be resealed after service. A temporary piercing valve is commonly installed near the sealed end of the process stub. Leak-test the fitting before recovery. Remove the solderless piercing fitting when service is complete because it can leak over time.
  11. Refrigerant identification and handling: Identify the refrigerant before recovery and keep different refrigerants in separate, clearly labeled cylinders. Let the appliance or recovery cylinder stabilize before comparing its pressure and temperature with the correct P-T chart. Pressure above the expected saturation value can indicate air, mixed refrigerant, or misidentification. R-134a became a common replacement for R-12 in newly manufactured household refrigerators, but it is not an automatic drop-in retrofit for an existing R-12 appliance.
  12. Service and safety: Use manual shutoff or self-sealing hose connections to minimize refrigerant releases. Recover vapor displaced from a graduated charging cylinder. If an opened access fitting reads 0 psig, do not begin normal recovery. Air or moisture may be present, and little or no refrigerant may remain. Do not fill a refillable recovery cylinder beyond 80% of its allowed capacity. Use the correct refillable, DOT-rated container for transport, label it, and never refill a disposable cylinder. Wear eye protection and suitable gloves. High heat can produce toxic and corrosive decomposition products. Large refrigerant releases can displace oxygen, especially in enclosed or low areas. Use nitrogen vapor through a pressure regulator and downstream relief valve.

EPA 608 Type I Most-Tested Numbers

NumberMeaning
5 poundsMaximum refrigerant charge for a small appliance. The appliance must also be fully manufactured, charged, and hermetically sealed at the factory.
15 poundsMaximum appliance charge for using system-dependent recovery equipment. Every Type I small appliance is within this limit.
November 15, 1993Dividing date for small-appliance recovery-equipment requirements. Equipment made or imported on or after this date must be certified by an EPA-approved testing organization and carry the required label.
90%Required percentage recovery when equipment made on or after November 15, 1993 is used on a small appliance with a working compressor.
80%Required percentage recovery when equipment made on or after November 15, 1993 is used on a small appliance with a failed compressor. Equipment made before November 15, 1993 also uses 80% regardless of compressor condition.
4 inches Hg vacuumAlternative to the percentage-based recovery requirement for a small appliance. The same vacuum alternative applies with working and failed compressors.
80% cylinder fillMaximum allowed fill level for a refillable recovery cylinder by weight. Use a scale or approved float device to monitor the fill level.
0 psig warningIf an access fitting is installed and opened and the appliance reads 0 psig, do not begin normal recovery into a cylinder containing usable recovered refrigerant. Air or moisture may be present, and little or no refrigerant may remain.
Quick calculations90% × 5 pounds = 4.5 pounds; 80% × 5 pounds = 4 pounds; 90% × 4 pounds = 3.6 pounds; 80% × 2.5 pounds = 2 pounds.

EPA 608 Type II

EPA 608 Type II Final Cram List

  1. Type II scope: Type II certification covers medium-, high-, and very-high-pressure appliances. It does not cover small appliances, low-pressure appliances, or motor vehicle air conditioning.
  2. Certification types: Type I covers small appliances. Type II covers medium-, high-, and very-high-pressure appliances. Type III covers low-pressure appliances. Universal covers all three types.
  3. Certification expiration: Section 608 technician certification does not expire.
  4. Refrigerant sales: Regulated refrigerants may generally be purchased only by properly certified technicians or businesses that employ certified technicians, subject to limited exceptions.
  5. Three Rs: Recover means remove and store refrigerant. Recycle means clean refrigerant for reuse. Reclaim means process refrigerant to the required purity standard and verify it by chemical analysis.
  6. Opening an appliance: Any service, maintenance, or repair that could release refrigerant is considered opening the appliance.
  7. Major repairs: Removing the compressor, condenser, evaporator, or auxiliary heat-exchanger coil is a major repair.
  8. Pressure classifications: R-134a is medium-pressure. R-22, R-404A, R-407C, and R-410A are high-pressure. R-13 and R-23 are very-high-pressure.
  9. Refrigeration cycle: The compressor takes in low-pressure vapor and sends out high-pressure vapor. The condenser changes vapor to liquid. The metering device lowers the pressure. The evaporator changes the refrigerant back to vapor.
  10. Receiver and accumulator: The receiver stores high-pressure liquid after the condenser. The accumulator keeps liquid refrigerant from entering the compressor.
  11. Service-valve positions: Back-seated closes the gauge port. Front-seated closes the line port. Mid-seated opens all ports.
  12. Common leak signs: Oil around a fitting can point to a leak. Low charge may cause high superheat. On an idle open-drive compressor, the rotating shaft seal is a common leak point.
  13. Leak-detection methods: Electronic and ultrasonic detectors help narrow the search area. Soap bubbles help pinpoint the exact leak location.
  14. Leak-test gas: Use dry nitrogen with a pressure regulator. If a trace gas is needed, use a small amount of the appliance’s design refrigerant. Never use oxygen or compressed air.
  15. Covered leak-repair appliances: EPA leak-repair requirements apply to appliances with at least 50 pounds of a Class I or Class II refrigerant, or a blend containing one.
  16. Trigger leak rates: Comfort cooling and other covered appliances use 10%. Commercial refrigeration uses 20%. Industrial process refrigeration uses 30%.
  17. Leak-rate calculation: The owner or operator must normally calculate the leak rate whenever refrigerant is added to a covered appliance, unless the addition qualifies as a seasonal variance or another listed exception.
  18. Leak-response options: When the trigger rate is exceeded, the owner must repair the leaks or follow the retrofit or retirement rules. The appliance may be properly mothballed to suspend the applicable deadlines temporarily.
  19. Repair deadline: Covered leaks must normally be repaired within 30 days. Industrial process refrigeration may receive 120 days when a process shutdown is required.
  20. Verification tests: A covered repair requires an initial verification test and a follow-up verification test. The follow-up test must be performed within 10 days of the successful initial test, or within 10 days after the appliance reaches normal operating conditions if it was evacuated for the repair.
  21. Mothballing: Evacuate the appliance or affected isolated section to at least atmospheric pressure and temporarily shut it down. Mothballing suspends the applicable deadline; it does not cancel it.
  22. Leak inspections: Commercial refrigeration and IPR appliances with at least 500 pounds require inspections every three months after exceeding the threshold. Smaller covered appliances generally require annual inspections.
  23. Recovery order: Recover liquid first because liquid recovery is faster. Recover the remaining vapor afterward.
  24. Speeding recovery: Use short, large-diameter hoses, cool the recovery cylinder, or safely warm the appliance.
  25. Preventing cross-contamination: Clear the old refrigerant from the recovery machine, service its filters as directed, evacuate the machine, and use the correct recovery cylinder.
  26. Pressure rise after recovery: Wait a few minutes after reaching the required level. Rising pressure may mean liquid remains, refrigerant is boiling out of the oil, or the appliance leaks.
  27. System-dependent recovery: Portable system-dependent recovery equipment may not be used on appliances containing more than 15 pounds of refrigerant.
  28. Service and leak exceptions: Qualifying non-major service may use the 0-psig exception. The oil-change exception allows no higher than 5 psig. If a leak prevents full evacuation, evacuate sound sections to the required level and the leaking section as low as possible, but not above 0 psig.
  29. Blends and dehydration: Zeotropic blends must normally be removed from the cylinder as liquid to prevent fractionation. Dehydration removes air, moisture, and noncondensables. Moisture can form acid or freeze, while noncondensables can cause high head pressure.
  30. Safety and exam traps: Never energize a hermetic compressor under a deep vacuum. Do not fill a recovery cylinder beyond 80% of its allowed capacity. Machinery-room safety includes refrigerant detection, alarms, and ventilation. Do not confuse EPA recovery levels with deep-vacuum dehydration. Remember: PSIA = PSIG + 14.7.

EPA 608 Type II Most-Tested Numbers

NumberMeaning
10% – 20% – 30%Comfort cooling and other covered appliances: 10%; commercial refrigeration: 20%; industrial process refrigeration: 30%.
5 – 15 – 50 – 200 – 500 poundsSmall appliance: 5 pounds or less; system-dependent recovery limit: 15 pounds; leak-repair coverage begins at 50 pounds; evacuation requirements split at 200 pounds; quarterly inspections begin at 500 pounds for commercial refrigeration and IPR.
November 15, 1993Main dividing date for recovery-equipment evacuation requirements.
0 – 4 – 10 – 15 inches Hg vacuumVery-high-pressure: 0. High-pressure under 200 pounds: 0. High-pressure at least 200 pounds: 4 with older equipment and 10 with newer equipment. Medium-pressure under 200 pounds: 4 with older equipment and 10 with newer equipment. Medium-pressure at least 200 pounds: 4 with older equipment and 15 with newer equipment.
0 psig / 5 psig0 psig applies to qualifying non-major service and mothballing. The oil-change exception allows no higher than 5 psig.
30 days / 120 daysStandard leak-repair deadline is 30 days; 120 days when an industrial process shutdown is required.
10 daysFollow-up verification must be completed within 10 days of the successful initial test, or within 10 days after normal operating conditions are reached when the appliance was evacuated.
125% / March 1Losing at least 125% of the full charge during a calendar year triggers chronic-leaker reporting. The report is due March 1 of the following year.
80% / 3 yearsDo not fill a recovery cylinder beyond 80% of its allowed capacity. The common EPA record-retention period is 3 years.
14.7 psiConvert gauge pressure to absolute pressure with PSIA = PSIG + 14.7.

EPA 608 Type III

EPA 608 Type III Final Cram List

  1. Scope and classification

    Type III certification covers low-pressure appliances, primarily centrifugal chillers.

    Common low-pressure refrigerants include:

    • R-11
    • R-123
    • R-245fa

    A low-pressure appliance is defined by its refrigerant’s liquid-phase saturation pressure. See the Type III Most-Tested Numbers section for the classification value.

  2. Why low-pressure chillers are different

    Low-pressure chillers commonly operate below atmospheric pressure.

    Because outside air is at a higher pressure:

    • Air and moisture tend to leak into the system
    • Refrigerant does not necessarily leak outward
    • Frequent purge-unit operation can indicate a leak
    • Excessive moisture at the purge unit may indicate leaking chiller tubes
    • Open-drive compressor shaft seals are a common leak location
  3. Purge units and noncondensables

    Air and other noncondensables collect near the top of the condenser.

    The purge unit:

    • Removes air and noncondensable gases
    • Separates refrigerant from the purge stream
    • Returns separated refrigerant to the system

    Noncondensables:

    • Occupy condenser space
    • Raise condenser pressure
    • Reduce heat transfer
    • Reduce system efficiency
  4. Leak testing

    Preferred pressurization order:

    1. Use controlled hot water or the chiller’s built-in heating or pressurization device
    2. Use regulated dry nitrogen if heating is insufficient

    Do not use compressed air or oxygen.

    A compliant leak inspection must locate the source of the leak.

    Methods that can locate leaks include:

    • Electronic leak detectors
    • Ultrasonic detectors
    • Bubble tests
    • Gas-imaging cameras

    These methods can show that leakage exists but cannot locate it by themselves:

    • Standing-pressure tests
    • Vacuum-decay tests
    • Sight-glass checks
    • Refrigerant-level checks
    • Charging-chart comparisons
  5. Leak-repair requirements

    EPA leak-repair requirements apply only when the appliance meets the refrigerant-type and charge-size requirements shown in the numbers section.

    When the applicable annual leak rate is exceeded, the owner or operator must:

    • Repair the leaks, or
    • Follow the retrofit or retirement requirements

    The owner or operator normally calculates the leak rate whenever refrigerant is added to a covered appliance.

    Covered repairs require:

    1. An initial verification test
    2. A follow-up verification test

    If a repair requires evacuation, perform the initial verification test before adding refrigerant.

    Commercial refrigeration and industrial process refrigeration appliances with larger charges have more frequent inspection requirements than smaller covered appliances and comfort-cooling appliances.

    Appliances that lose an exceptionally large percentage of their full charge during a calendar year are subject to chronic-leaker reporting.

  6. Major repairs

    A major repair includes removing the:

    • Compressor
    • Condenser
    • Evaporator
    • Auxiliary heat-exchanger coil

    Replacing a filter-drier, pressure switch, metering device, service-port cap, or purge unit is not normally a major repair.

    Maintenance, service, or repair is also considered major when it uncovers an opening of more than 4 square inches of refrigerant flow area for more than 15 minutes.

  7. Recovery sequence
    1. Recover liquid first because liquid recovery is faster
    2. Recover the remaining vapor
    3. Reach the required evacuation level
    4. Isolate the recovery machine
    5. Wait several minutes and watch for a pressure rise

    A pressure rise may mean:

    • Liquid refrigerant remains
    • Refrigerant is boiling out of the oil
    • The appliance is leaking

    Do not assume recovery is complete merely because all visible liquid has been removed. A large chiller can still contain a substantial refrigerant charge as vapor.

  8. Water and freezing protection

    Evacuation lowers refrigerant pressure and saturation temperature.

    If water remains in the chiller:

    • Keep it circulating, or
    • Remove it before evacuation

    Stagnant water can freeze and damage the chiller tubes.

  9. Oil removal

    Heat the oil before draining it.

    Heating drives dissolved refrigerant out of the oil so that it can be recovered instead of released during draining.

  10. When the appliance leaks during recovery

    If a leak prevents the prescribed evacuation level from being reached:

    1. Isolate leaking and non-leaking sections when possible
    2. Evacuate non-leaking sections to the prescribed level
    3. Evacuate the leaking section as low as practical without substantially contaminating the recovered refrigerant
  11. Non-major repairs

    The preferred way to bring a low-pressure appliance to atmospheric pressure for a non-major repair is to warm the refrigerant already in the appliance.

    Use:

    • Controlled hot water, or
    • An approved built-in heating or pressurization device
  12. Charging sequence
    1. Introduce refrigerant vapor first
    2. Raise the refrigerant pressure and saturation temperature above the freezing danger
    3. Introduce liquid refrigerant through the evaporator charging valve

    Adding liquid directly into a deep vacuum can cause rapid boiling, freeze water in the tubes, and damage the chiller.

  13. Pressure–temperature relationship
    • Pressure rises → saturation temperature rises
    • Pressure falls → saturation temperature falls

    Pressure-temperature charts show saturation conditions at a given pressure.

    Superheat equals:

    Measured vapor temperature − saturation temperature

  14. Machinery-room safety

    ASHRAE Standard 15 covers refrigeration-system and machinery-room safety.

    Refrigerants can displace breathable air, creating an oxygen-deficient atmosphere.

    Machinery-room protections include:

    • Oxygen monitoring
    • Alarms
    • Mechanical ventilation

    R-123 machinery rooms also require refrigerant detection because R-123 presents a toxicity concern.

    R-123 has a B1 safety classification:

    • B = higher toxicity
    • 1 = no flame propagation

    Use the Type III Most-Tested Numbers section for evacuation levels, pressure limits, leak thresholds, deadlines, and temperature values.

EPA 608 Type III Most-Tested Numbers

NumberMeaning
Below 45 psia at 104°FLow-pressure appliance classification
50 lbCovered refrigerant charge at which leak-repair requirements generally begin
10%Comfort-cooling and other covered-appliance leak-rate threshold
20%Commercial refrigeration leak-rate threshold
30%Industrial process refrigeration leak-rate threshold
500 lbQuarterly inspection threshold for commercial refrigeration and IPR appliances exceeding the applicable leak rate
30 daysStandard leak-repair deadline
120 daysLeak-repair deadline when an industrial process shutdown is required
10 daysFollow-up verification-test deadline
125%Chronic-leak reporting threshold during one calendar year
March 1Chronic-leak report deadline for the previous calendar year
25 mm Hg absoluteLow-pressure evacuation level before a major repair or disposal
0 psigHighest permitted level for a leaking section when the prescribed evacuation level cannot be attained
10 psigMaximum low-pressure chiller leak-test pressure
10 psigTypical recovery-unit high-pressure cutout
15 psigTypical low-pressure chiller rupture-disc rating
The three commonly confused pressures: 10 psig for leak testing, 10 psig for the recovery-unit cutout, and 15 psig for the rupture disc.
NumberMeaning
130°FApproximate oil temperature before draining
Approximately 100 lbVapor remaining in an average 350-ton R-123 chiller at 0 psig after liquid removal
20 in. Hg vacuumCommon R-123 charging reference before introducing liquid
14.7 psiaStandard atmospheric pressure
14.7 psia = 0 psigAbsolute-to-gauge pressure reference
PSIA = PSIG + 14.7Pressure-conversion formula
3 yearsCommon EPA record-retention period

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Core Type I Type II Type III Universal