EPA 608 Core practice test

1. A technician assembles a split air-conditioning system on site and charges it with 4 pounds of refrigerant. Does it fit EPA's description of a "small appliance"?

• A. Yes, because its charge is under five pounds
• B. Yes, because every air conditioner counts as a small appliance
• C. No, because a small appliance must be fully manufactured, charged and hermetically sealed in a factory
• D. No, because a small appliance must hold less than one pound of refrigerant

2. Under the Section 608 definitions, which parts of an appliance make up its "refrigerant circuit"?

• A. Only the compressor and the condenser
• B. Every part of the appliance, including the cabinet and the wiring
• C. Only the parts that hold liquid refrigerant
• D. The parts that are normally connected to each other, or separated only by internal valves, and are designed to contain refrigerant

3. The definition of an MVAC-like appliance, such as the air conditioning on a farm tractor, sets what limit on its full charge of refrigerant?

• A. 5 pounds or less
• B. 50 pounds or more
• C. 20 pounds or less
• D. 2 pounds or less

4. How does the definition of "appliance" treat a system that has multiple independent refrigerant circuits?

• A. The whole system counts as one appliance
• B. Only the largest circuit counts as an appliance
• C. The system counts as an appliance only if all circuits share a compressor
• D. Each independent circuit is considered a separate appliance

5. A hotel's own maintenance employee, not an outside contractor, removes a component from the refrigerant circuit of the hotel's rooftop air conditioner. How does the definition of "technician" treat this employee?

• A. As a technician, because removing components can violate the refrigerant circuit and in-house personnel are covered
• B. As outside the definition, because only outside contractors can be technicians
• C. As outside the definition, because work on the owner's own equipment is not covered
• D. As a technician only if the rooftop unit is a small appliance

6. Under the rule's definition, connecting and disconnecting hoses and gauges to measure pressures is:

• A. Not considered "opening an appliance"
• B. Considered opening an appliance only on low-pressure appliances
• C. Considered opening an appliance in all cases
• D. Considered opening an appliance if the hoses stay connected for more than 15 minutes

7. Besides removing a compressor, condenser, evaporator or auxiliary heat exchange coil, which work counts as "major" maintenance, service or repair?

• A. Uncovering an opening of more than 4 square inches of flow area for more than 15 minutes
• B. Uncovering an opening of more than 1 square inch of flow area for more than 60 minutes
• C. Uncovering any opening for more than 5 minutes
• D. Uncovering an opening of more than 10 square inches of flow area for any length of time

8. A walk-in cooler uses R-134a. Under the definitions, which pressure class of appliance is it?

• A. Low-pressure appliance
• B. High-pressure appliance
• C. Medium-pressure appliance
• D. Very high-pressure appliance

9. A shop takes apart a discarded rooftop unit only to reuse its compressor in another unit. Does this fall under the rule's definition of "disposal"?

• A. No, because disposal covers only placing a discarded appliance into or on land or water
• B. No, because disposal covers only recycling an appliance for scrap
• C. Yes, but only when the appliance is a small appliance
• D. Yes, because the disassembly of any appliance for reuse of its component parts is part of disposal

10. An owner determines an appliance's full charge using an established range based on the best available data about the appliance's normal operating characteristics and conditions. Which value serves as the full charge?

• A. The top of the range
• B. The bottom of the range
• C. The total amount of refrigerant added over the last 12 months
• D. The midpoint of the range

11. At a supply house, a worker pulls the leftover "heel" of refrigerant out of empty refrigerant cylinders. According to EPA, does this work require Section 608 certification?

• A. Yes, because a refrigerant cylinder is a small appliance
• B. Yes, whenever the cylinder was designed to hold more than five pounds
• C. Only when the cylinder held a class I refrigerant
• D. No, because cylinders that store or transport bulk refrigerant are not considered appliances

12. Before replacing a compressor, a technician pumps a rooftop unit's charge into a cylinder without filtering or testing it. How do EPA's definitions classify this step?

• A. Reclaiming, because the refrigerant goes into a cylinder
• B. Recovering, because it is removed and stored without necessarily being tested or processed
• C. Recycling, because the refrigerant leaves the appliance
• D. None of the three Rs, until the refrigerant has been tested

13. A contractor with no certified technician on staff wants to buy refrigerant for use in its customers' appliances. Its manager offers to sign a promise not to vent it. Under EPA's sales restriction, may the seller go ahead?

• A. Yes, because a signed promise not to vent satisfies the rule
• B. No, because the buyer must be, or employ, a certified technician
• C. Yes, if the contractor pays in advance
• D. Yes, if the cylinder holds less than 30 pounds

14. A technician recovers refrigerant from one customer's rooftop unit and wants to charge it into a unit owned by an unrelated company. According to EPA's service practice requirements, what must happen to the refrigerant first?

• A. It must be reclaimed by an EPA-certified reclaimer
• B. It must sit in a recovery cylinder for 30 days
• C. It must be checked with a refrigerant identifier by the technician
• D. The second company must sign a statement accepting it

15. A property management company owns two office buildings. A technician recovers refrigerant from a unit in the first building. According to EPA's service practice requirements, where may that refrigerant go without being reclaimed?

• A. Into a cylinder sold to another contractor
• B. Into a unit in a neighboring building owned by a different firm
• C. Into any unit the same technician services that week
• D. Into a unit in the second building, because the same company owns it

16. A store sells a container of non-exempt substitute refrigerant intended for use in an MVAC to a buyer with no certification. Which container matches the sales-restriction exception for this refrigerant?

• A. One designed to hold five pounds or less, with any standard fitting
• B. One designed to hold two pounds or less, with a unique fitting and, if manufactured or imported on or after January 1, 2018, a compliant self-sealing valve
• C. One designed to hold two pounds or less, with no other condition
• D. One designed to hold 20 pounds or less, the same limit as an MVAC-like appliance's charge

17. A distributor sells a 25-pound cylinder of a non-exempt substitute refrigerant for stationary equipment to a certified technician. What must the distributor's invoices indicate?

• A. The name of the purchaser, the date of sale, and the quantity of refrigerant purchased
• B. The purchaser's home address and phone number
• C. The appliance the refrigerant will be charged into
• D. The purchaser's certification test score

18. An online store takes a technician's refrigerant order and payment, and a separate distributor ships the cylinder. According to EPA, who is responsible for verifying the technician's certification?

• A. Only the online store that took the payment
• B. All of the sellers and distributors in the transaction
• C. Only the distributor that ships the cylinder
• D. Only the technician, by keeping the card on file

19. At a supply house counter, a technician shows a Section 608 card issued by a certifying program that is no longer EPA-approved. According to EPA, when is the card still valid?

• A. When it was issued during the period in which the certifying program was approved
• B. Only after the technician has it reissued with the newer card wording
• C. Only if it was issued within the last three years
• D. Never, because cards from programs that lose approval are void

20. A technician who holds only Section 609 certification asks a supplier for a small container of HCFC-22 (R-22). According to EPA's page on the Section 608 and 609 overlap, may the supplier sell it?

• A. Yes, if the container holds two pounds or less
• B. Yes, because Section 609 certification covers every refrigerant
• C. Yes, if the technician signs a statement promising not to vent it
• D. No; Section 609 technicians cannot purchase HCFC-22 in any size container

21. A contractor wants to sell online a used condensing unit taken from an air conditioner, with used refrigerant still inside it. What does EPA say?

• A. It may be sold charged if the buyer is a certified technician
• B. It may be sold charged if it holds five pounds of refrigerant or less
• C. Used components such as a condensing unit cannot contain used refrigerant when sold
• D. It may be sold charged, because components are treated like complete appliances

22. A contractor has recovered refrigerant that it will not return to systems owned by the same customer. According to EPA's reclamation page, where can the contractor return it?

• A. To another customer's system, if that customer agrees in writing
• B. To a consolidator, such as a refrigerant manufacturer, supplier, wholesale distributor or refrigerant recovery company, or in some cases directly to an EPA reclaimer
• C. To any certified technician who buys it through an online marketplace
• D. To the nearest EPA Regional Office for disposal

23. An EPA inspector visits a refrigeration contractor's shop while one of its certified technicians is out on a service call with the original wallet card. Under 40 CFR 82.161, what must be kept at the technician's place of business?

• A. A copy of the technician's certificate
• B. A letter from EPA confirming the certification
• C. Nothing, because the wallet card travels with the technician
• D. The technician's graded test answer sheet

24. How long must a technician keep a copy of their Section 608 certification?

• A. For five years after the test date
• B. For one year after the test date
• C. Until three years after they are no longer operating as a technician
• D. Only until they receive the plastic card

25. A technician earned Type II certification in 1995 and has not taken another Section 608 test since. According to EPA, what is the status of that credential today?

• A. It lapsed after 20 years
• B. It must be renewed by retesting with the original program
• C. It covers only the refrigerants that were in use in 1995
• D. It is still valid, because Section 608 certification credentials do not expire

26. A technician has lost their Section 608 certification card. Who should they contact for a replacement?

• A. The company that certified them, whose name is on the card
• B. The EPA Regional Office
• C. The refrigerant wholesaler where they buy refrigerant
• D. Their state environmental agency

27. A technician has passed the Core and Type I sections at a proctored, closed-book session and now wants Universal certification. According to EPA, what else is needed?

• A. Nothing; Core plus Type I already counts as Universal
• B. Two years of work under a Universal technician
• C. Passing the Type II and Type III examinations, so that all levels have been passed
• D. A written request to EPA for an upgraded card

28. Is Section 608 certification needed to add or remove refrigerant from a mini-split system as part of installation?

• A. No, installation is exempt
• B. Yes, Section 608 technician certification is required
• C. Only for commercial buildings
• D. Only if the system holds more than 50 pounds

29. Technicians who maintain, service or repair MVAC-like appliances must hold which certification?

• A. Type I only
• B. No certification, because MVAC-like appliances are exempt
• C. Type III only
• D. Type II, or certification under 40 CFR part 82, subpart B

30. Under what condition is a registered apprentice exempt from the technician certification requirement?

• A. When the apprentice has passed the Core section only
• B. When the apprentice is closely and continually supervised by a certified technician
• C. When the apprentice works only on weekends
• D. When the apprentice's employer files a notice with EPA

31. A technician holds only Type I certification and is asked to repair a rooftop air conditioner charged with R-410A that is not a small appliance. Which certification type does the rule tie to this kind of appliance?

• A. Type I, because the technician is already certified
• B. Type II, because R-410A appliances are high-pressure appliances
• C. Type III, because rooftop units are low-pressure appliances
• D. None, because repairing an appliance never requires certification

32. A certified technician left the wallet card at the office before a service call. Does EPA require technicians to carry their certification card when servicing appliances?

• A. Yes, the original card must be on the technician during all refrigerant work
• B. Yes, the card must be shown to the customer before any work starts
• C. Yes, a photocopy of the card must be kept in the service vehicle
• D. No; EPA does not require it, although some customers may ask for proof of certification

33. A job applicant's only refrigerant credential is an "R-410A certification" from a trade school class. According to EPA, does it take the place of Section 608 certification for servicing R-410A systems?

• A. Yes, for R-410A systems only, because R-410A is not an ozone-depleting substance
• B. Yes, it counts as Universal certification
• C. Yes, as long as the applicant also passes the Core section
• D. No; such R-410A certifications are not equivalent to a section 608 certification, which EPA requires based on the type of appliance

34. An HVAC student who is neither certified nor a registered apprentice wants to recover refrigerant on a contractor's real service calls as on-the-job training. What does EPA say?

• A. It is allowed, because all training counts as laboratory course work
• B. It is allowed if the student's instructor signs off on each job afterward
• C. On-the-job training is considered maintenance, service, repair or disposal, so the student must be certified or a registered apprentice
• D. It is allowed only on appliances holding less than 50 pounds of refrigerant

35. A technician lost their Section 608 card. The organization that certified them is out of business, and they have no certificate, receipt, test score or other documentation of the certification. According to EPA, how can they get a valid card?

• A. By signing a statement that they passed, which any approved program must accept
• B. By asking EPA to look them up in its national database of technicians and issue a card
• C. By arranging with an approved Section 608 program to retake the exam
• D. By asking their refrigerant supplier to issue a replacement card

36. Section 608 technician certification is required to dispose of appliances, except for which type of appliance?

• A. Low-pressure chillers
• B. High-pressure appliances
• C. Small appliances
• D. Very high-pressure appliances

37. EPA's safe disposal page places responsibility on the final person in the disposal chain to make sure refrigerant is recovered. Which kind of equipment does that responsibility cover?

• A. Large chillers that technicians take apart on site
• B. Equipment that enters the waste stream with its charge intact, such as household refrigerators and freezers or window air conditioners
• C. Commercial rooftop units removed by service contractors
• D. Only equipment that contains exempt refrigerants

38. A scrap recycler receives a refrigerator carrying only an unsigned sticker that reads "refrigerant removed." According to EPA's safe disposal page, how should the recycler treat the sticker?

• A. As full verification, because the sticker says the refrigerant is gone
• B. As not acceptable verification; the recycler must still verify recovery, for example with a signed statement giving the name and address of the person who recovered the refrigerant and the date it was recovered
• C. As full verification, if the sticker is dated
• D. As full verification, if a certified technician applied it

39. Each month a technician evacuates refrigerant from several appliances with a full charge of 20 pounds so they can be disposed of. Besides the record kept for each appliance, which monthly record must the technician keep?

• A. The leak rate of each appliance in its final month of use
• B. The serial number of every recovery cylinder used that month
• C. The price paid by the scrap recycler for each appliance
• D. The total quantity of refrigerant, by type, recovered from all disposed appliances in each calendar month

40. A shop still uses a recovery machine built in 1991. Under EPA's service practice requirements, which requirement does the machine's age excuse it from?

• A. Certification by an EPA-approved equipment testing organization
• B. Recovery of refrigerant before the appliance is opened
• C. Use by a certified technician
• D. The prohibition on venting refrigerant

41. For an oil change, EPA's service practice page sets a pressure limit before the system is opened. Instead of bringing the whole appliance to that limit, what other option does EPA describe?

• A. Draining the oil into a receiver that is evacuated or pressurized to no more than 5 psig
• B. Draining the oil into an open container while the system runs
• C. Changing the oil at full system pressure if the job takes under 15 minutes
• D. Venting the vapor charge first so the oil drains freely

42. For leaking equipment, EPA says leaking components should be evacuated to the lowest level that can be reached without doing what?

• A. Running the recovery machine for more than one hour
• B. Substantially contaminating the refrigerant
• C. Adding nitrogen to the system
• D. Disconnecting the recovery hoses

43. A technician's recovery cylinder already holds one refrigerant, and the next job uses a different refrigerant. Which point do EPA's Core recovery-technique topics make?

• A. Mixing refrigerants is encouraged so that cylinders are used fully
• B. Mixing refrigerants is fine if both are HFCs
• C. Mixing refrigerants matters only for small appliances
• D. Technicians need to avoid mixing refrigerants

44. A recovery job is going slowly. Which factors do EPA's Core test topics list as affecting the speed of recovery?

• A. The color of the recovery cylinder and the brand of the refrigerant
• B. Ambient temperature, the size of the recycling or recovery equipment, and hose length and diameter
• C. The technician's certification type and the date of the test
• D. Only the age of the appliance

45. Why does EPA require the pressure to be reduced before a technician changes the oil in a refrigeration appliance?

• A. Because oil cannot drain while the compressor is cold
• B. Because used refrigerant oil is an exempt refrigerant
• C. Because the oil can contain large amounts of dissolved refrigerant, the bulk of which must be recovered
• D. Because lowering the pressure makes the oil safe to pour on the ground

46. A technician has finished a repair and is about to return the system to service. According to EPA's Core topics on dehydration evacuation, why is the system evacuated at the end of service?

• A. To raise the refrigerant pressure before charging
• B. To eliminate air and moisture
• C. To release leftover refrigerant to the atmosphere
• D. To add oil to the compressor

47. EPA's Core test topics link the destruction of ozone to chlorine. In which refrigerant families do the topics say chlorine is present?

• A. HFCs only
• B. HFCs and HCFCs
• C. CFCs and HCFCs
• D. CFCs only

48. In the ozone-depletion potential (ODP) comparison in EPA's test topics, which family has a higher ODP than HFCs but a lower ODP than CFCs?

• A. CFCs
• B. HCFCs
• C. HFCs
• D. None; the three families have the same ODP

49. A technician has three appliances to recover, charged with R-12, R-22 and R-134. Which grouping matches EPA's Core test topics on identifying refrigerant families?

• A. R-12 is an HCFC, R-22 is a CFC, R-134 is an HFC
• B. R-12 is a CFC, R-22 is an HCFC, R-134 is an HFC
• C. R-12 is an HFC, R-22 is an HCFC, R-134 is a CFC
• D. R-12 is a CFC, R-22 is an HFC, R-134 is an HCFC

50. A customer asks why releasing even a little refrigerant matters to the ozone layer. Which statement about chlorine appears on EPA's ozone science page?

• A. One chlorine atom can destroy over 100,000 ozone molecules before it is removed from the stratosphere
• B. Each chlorine atom is used up after it destroys a single ozone molecule
• C. Chlorine destroys ozone only in the troposphere, where people live
• D. Ozone is always created faster than chlorine can destroy it

51. Ozone layer depletion increases the amount of UVB radiation that reaches the Earth's surface. Which human health effects does EPA link to UVB?

• A. Skin cancer and cataracts
• B. Hearing loss
• C. Kidney stones
• D. Lead poisoning

52. A customer claims that chlorine from swimming pools and sea salt harms the ozone layer more than refrigerant does. What does EPA say about those chlorine sources?

• A. They are the main source of chlorine in the stratosphere
• B. They reach the stratosphere faster than CFCs do
• C. Their chlorine does not reach the stratosphere
• D. They destroy ozone only over Antarctica

53. EPA gives the annual ozone "hole" over Antarctica as one example of ozone depletion. How does EPA describe it?

• A. A hole that goes all the way through the ozone layer and stays open all year
• B. A gap that is caused mainly by volcanic eruptions
• C. Not really a hole, but a large area of the stratosphere with extremely low amounts of ozone
• D. The only place where ozone depletion occurs

54. According to EPA's Refrigerant Safety page, which property of CFCs lets them carry ozone-depleting chlorine to the stratosphere and keeps them in the atmosphere as greenhouse gases for a long time?

• A. Their tendency to break down quickly in rain
• B. Their high flammability
• C. Their high stability
• D. Their high toxicity

55. EPA's Core safety topics name two gases that should not be used for leak detection. Which pair is it?

• A. Nitrogen and oxygen
• B. Nitrogen and helium
• C. Oxygen and compressed air
• D. Compressed air and nitrogen

56. A technician plans to connect a nitrogen cylinder straight to a system for a pressure test, with nothing else in the line. Which equipment do EPA's Core safety topics say belongs with nitrogen?

• A. A vacuum pump and a micron gauge
• B. A pressure regulator and a relief valve
• C. A refrigerant scale and a recovery cylinder
• D. A refrigerant identifier and a sight glass

57. A customer with an R-22 home air conditioner has seen a product called "R-22a" marketed as an R-22 replacement. What does EPA's HCFC-22 fact sheet say about it?

• A. It is a hydrocarbon blend whose main components include propane and butane; it is highly flammable and not an acceptable alternative for a residential AC system
• B. It is HCFC-22 with a small additive, so it may be mixed with the existing charge
• C. It is an HFC listed as acceptable for retrofitting residential AC systems
• D. It is reclaimed HCFC-22 sold under a new name after reprocessing

58. Which risks of exposure to refrigerant do EPA's Core safety topics give as examples?

• A. Oxygen deprivation, cardiac effects, frostbite and long-term hazards
• B. None, because refrigerants are harmless to people
• C. Only mild skin irritation
• D. Only hearing damage from cylinder noise

59. A technician is getting ready to recover refrigerant. Which personal protective equipment do EPA's Core safety topics name?

• A. Hearing protection only
• B. A paper dust mask instead of goggles
• C. None, because refrigerant work needs no protective equipment
• D. Gloves and goggles, with a self-contained breathing apparatus (SCBA) in extreme cases

60. A technician picks up a cylinder to hold refrigerant recovered on a job. Which description matches what EPA's Core safety topics say about reusable (recovery) cylinders?

• A. Single-use cylinders that are thrown away once empty
• B. Any cylinder at all, as long as it is painted solid green
• C. Department of Transportation (DOT) approved, with a yellow and gray color code
• D. Unmarked cylinders, because recovered refrigerant needs no particular container

61. A disposable refrigerant cylinder is empty, and a technician wants to put recovered refrigerant in it. What do EPA's Core safety topics say about disposable cylinders?

• A. Never refill them
• B. Refill them only once
• C. Refill them only with the refrigerant they first held
• D. Refill them after painting them yellow and gray

62. While filling a cylinder with recovered refrigerant, which fill level do EPA's Core safety topics single out as a risk?

• A. Less than 20 percent full
• B. Exactly half full
• C. Any amount, because recovery cylinders must stay empty
• D. More than 80 percent full

63. EPA's Refrigerant Safety page says that high exposures to refrigerant can happen for brief periods during some service operations. Which example does it give?

• A. Checking the thermostat setting
• B. Opening a compressor or removing a gasket that may have refrigerant trapped under it
• C. Painting the appliance cabinet
• D. Rewiring an external electrical circuit

64. A technician has filled a recovery cylinder and tagged it with the name of the refrigerant inside. Before the cylinder is shipped, which other label do EPA's Core shipping topics list for refrigerant cylinders?

• A. A label with the technician's certification number
• B. A DOT classification tag
• C. A label with the serial number of the appliance it came from
• D. A label with the date of the last leak test

65. A technician recovers a non-exempt refrigerant into a cylinder and later knowingly releases it outdoors. Under the rule, this release is:

• A. Allowed, because the refrigerant was already removed from the appliance
• B. Allowed as a de minimis release
• C. Allowed if certified recovery equipment was used
• D. A violation of the venting prohibition

66. For a release of a non-exempt refrigerant to count as de minimis under the venting prohibition, which situation can make it qualify?

• A. It happens outdoors
• B. It is less than one pound of refrigerant
• C. The technician reports it to EPA within 30 days
• D. It happens while the required service practices, certified recovery machines, technician certification and reclamation requirements are all observed

67. A technician services a split system charged with an HFC refrigerant blend. Do the Section 608 requirements, including the ban on knowingly releasing refrigerant, cover this refrigerant?

• A. No, because they cover only CFCs
• B. No, because they cover only refrigerants that contain ozone-depleting substances
• C. Yes, because they cover non-exempt substitute refrigerants such as HFCs and blends of them
• D. No, because HFC blends are exempt refrigerants, like carbon dioxide, nitrogen and water

68. EPA says only three types of refrigerant releases are permitted under the venting prohibition. Which of these is one of them?

• A. Releasing a system's charge to save time before replacing a compressor
• B. Refrigerant emitted during the normal operation of the equipment, such as from mechanical purging and leaks
• C. Venting recovered refrigerant from a full recovery cylinder
• D. Venting the charge when an appliance is scrapped

69. In which uses is ammonia an exempt substitute under the venting prohibition?

• A. In any application
• B. Only in household refrigerators
• C. In commercial or industrial process refrigeration or in absorption units
• D. Only in motor vehicle air conditioners

70. A blend that consists only partly of a class II ozone-depleting substance is used for heat transfer purposes and provides a cooling effect. How does the rule's definition of refrigerant treat it?

• A. It is not a refrigerant, because only pure substances count
• B. It is a refrigerant only if more than half of the blend is a class II substance
• C. It is a refrigerant only when used in an MVAC
• D. It is a refrigerant, because the definition includes blends and mixtures consisting in part or whole of a class I or class II substance or substitute

71. The Kigali Amendment (2016) extended Montreal Protocol controls to phase down the production and consumption of HFCs. What reason does EPA give for this?

• A. HFCs were adopted by industries moving away from ozone-depleting substances, and they are potent greenhouse gases
• B. HFCs release chlorine that destroys stratospheric ozone
• C. HFCs have a higher ozone depletion potential than CFCs
• D. HFCs are flammable hydrocarbons that are unsafe in homes

72. In 2026, a homeowner's working central air conditioner runs on HCFC-22 (R-22). The homeowner asks whether the system must be replaced or converted now that U.S. production and import of HCFC-22 have ended. What does EPA's fact sheet say?

• A. The system must be retrofitted to a non-ozone-depleting alternative at its next service
• B. The system may run only until its current charge needs topping up
• C. The homeowner may continue to use HCFC-22 in the existing system for as long as necessary
• D. The system must be replaced by January 1, 2030

73. A salesperson tells a technician that a substitute refrigerant is a "drop-in" replacement for the CFC in an older system. What do EPA's Core test topics on substitute refrigerants say about drop-in replacements?

• A. Every substitute refrigerant is a drop-in replacement
• B. Drop-in replacements exist for all CFC and HCFC refrigerants
• C. The Clean Air Act requires every substitute to be a drop-in replacement
• D. The topics point to the absence of drop-in replacements

74. A technician is choosing compressor oil for two systems, one charged with R-134 and one with an HCFC. Which refrigerant and lubricant pairings do EPA's Core test topics give as examples?

• A. Esters with R-134, and alkylbenzenes for HCFCs
• B. Alkylbenzenes with R-134, and esters for HCFCs
• C. Any lubricant with either refrigerant, because refrigerants and lubricants are always compatible
• D. Glycol engine coolant with R-134, and no lubricant for HCFCs

75. A system charged with a refrigerant blend has been leaking for weeks. Which problem with blends do EPA's Core test topics name?

• A. Decomposition of the blend into a toxic gas at room temperature
• B. Freezing of the blend inside the lines at room temperature
• C. Fractionation, the tendency of different components of blends to leak at different rates
• D. Blends cannot leak, because their components hold each other in

76. A customer asks why U.S. rules on ozone-depleting refrigerants exist when the ozone layer is a worldwide problem. How does EPA describe the link between the Montreal Protocol and U.S. law?

• A. The Montreal Protocol was signed in 1987, and the United States passed Title VI of the Clean Air Act in 1990 to fulfill its obligations
• B. The Montreal Protocol is a U.S. law that replaced the Clean Air Act in 1990
• C. Title VI of the Clean Air Act was passed first, and the Montreal Protocol later copied it for other countries
• D. The Montreal Protocol is the industry standard that sets the purity of reclaimed refrigerant

77. In 1992, after new data showed worse-than-expected damage to the ozone layer, the Parties to the Montreal Protocol changed the 1987 agreement. By what year did they decide to end CFC production in developed countries?

• A. 1987
• B. 2030
• C. 2020
• D. 1996

78. A technician servicing older equipment wants to know when the United States stopped producing and importing HCFC-22 (R-22). Which date does EPA's fact sheet give?

• A. January 1, 1987
• B. January 1, 2020
• C. January 1, 1996
• D. January 1, 2035

79. In the United States, ozone-depleting substances are regulated as class I or class II controlled substances. Which class are HCFCs such as R-22?

• A. Class II, the transitional substitutes for many class I substances
• B. Class I, the class with the higher ozone depletion potential
• C. Neither, because HCFCs are not ozone-depleting substances
• D. Class III, a separate class for refrigerant blends