EPA 608 Core Practice Test – Free Questions with Answers
Ozone, the Clean Air Act, the 3 Rs, recovery, evacuation, safety and shipping. Every technician must pass Core. Tap an answer to check it.
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Question 1
Which element in CFC and HCFC refrigerants destroys stratospheric ozone?
UV light breaks chlorine free from CFC and HCFC molecules high in the stratosphere. One chlorine atom can destroy many thousands of ozone molecules.
Question 2
R-12 is what type of refrigerant?
R-12 (and R-11, R-500, R-502) are CFCs: chlorine, fluorine and carbon, no hydrogen.
Question 3
R-22 is what type of refrigerant?
R-22 and R-123 are HCFCs. The hydrogen makes them break down sooner in the lower atmosphere, so they deplete less ozone than CFCs.
Question 4
R-134a is what type of refrigerant?
R-134a, R-410A and R-404A are HFCs. They contain no chlorine, so their ozone depletion potential is zero.
Question 5
Put these refrigerant types in order of ozone depletion potential (ODP), highest first.
CFCs have the highest ODP, HCFCs are lower, and HFCs have none because they contain no chlorine.
Question 6
Why do CFCs reach the stratosphere?
CFCs are so stable that they survive for decades and slowly drift up to the stratosphere, where UV light finally breaks them apart.
Question 7
A loss of stratospheric ozone leads to more of which kind of radiation reaching the earth?
The ozone layer filters UV-B. Less ozone means more UV-B at ground level.
Question 8
Which is a health or environmental effect of ozone depletion?
More UV-B raises the risk of skin cancer and cataracts, weakens the immune system and harms crops and marine life.
Question 9
What is the evidence that CFCs and HCFCs cause ozone depletion?
Measurements show high chlorine levels in the stratosphere matching the rise of CFC use, together with the ozone hole over Antarctica.
Question 10
HFC refrigerants do not deplete ozone, but what is their environmental concern?
HFCs are strong greenhouse gases. That is why venting them is prohibited and why they are being phased down under the AIM Act.
Question 11
What is the Montreal Protocol?
The Montreal Protocol (1987) is the international treaty that phases out the production of CFCs, HCFCs and other ozone-depleting substances.
Question 12
When did production of CFCs end in the United States?
CFC production and import ended at the end of 1995. CFCs still in use come from recovered, recycled or reclaimed stock.
Question 13
Since January 1, 2020, what is no longer allowed for R-22?
Since 2020 no new R-22 may be produced or imported. Existing systems can still be serviced with recovered, recycled or reclaimed R-22.
Question 14
Under the Clean Air Act, intentionally venting CFC or HCFC refrigerant during service is:
Venting has been prohibited since July 1, 1992. Only de minimis releases that happen while following proper recovery practices are allowed.
Question 15
Does the venting prohibition also apply to substitute refrigerants such as HFCs?
Since November 15, 1995 knowingly venting substitute refrigerants (like HFCs) is also prohibited. Some exempt substitutes exist, but the exam expects you to know that HFCs may not be vented.
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▶ Get it on Google PlayQuestion 16
Which release of refrigerant is NOT a violation (de minimis)?
De minimis releases are the small amounts that escape while you follow the required recovery and recycling practices.
Question 17
What is the maximum civil penalty under the Clean Air Act for a refrigerant violation?
The law sets $25,000 per day per violation, adjusted every year for inflation: $124,426 in 2025. Older study guides list $27,500, $37,500 or $44,539. On the test, pick the largest per-day amount offered. A reward of up to $10,000 can be paid to people who report violations.
Question 18
Who may buy refrigerant in containers for stationary equipment under the sales restriction?
The sales restriction limits the sale of refrigerant for stationary systems to certified technicians, with a few exceptions (for example, small cans for car A/C and refrigerant sold inside pre-charged appliances).
Question 19
Which equipment is covered by the Section 608 rules?
Section 608 covers stationary refrigeration and A/C. Motor vehicle air conditioners (MVACs) are covered by Section 609 instead.
Question 20
Does Section 608 technician certification expire?
Section 608 certification does not expire. Keep your card: you need it to buy refrigerant. Lost cards are replaced by the program that certified you.
Question 21
Recovery and recycling equipment must be:
Recovery/recycling machines must be certified by an EPA-approved testing organization such as UL or Intertek (ETL).
Question 22
Reclaimed refrigerant must meet which purity standard before it is resold?
Reclaimed refrigerant must be processed by an EPA-certified reclaimer to the purity of AHRI Standard 700 before it can be sold to a new owner.
Question 23
What is the difference between system-dependent and self-contained recovery equipment?
Self-contained (active) recovery machines have their own compressor. System-dependent (passive) recovery relies on the appliance's own compressor or internal pressure.
Question 24
Which refrigerant is used in low-pressure appliances?
Under the rule, a low-pressure appliance uses a refrigerant with a saturation pressure below 45 psia at 104°F. Examples: R-11, R-123, R-113 and R-245fa, used in centrifugal chillers.
Question 25
Under the Section 608 definitions, R-22 and R-410A are used in which kind of appliance?
The classes are based on saturation pressure at 104°F: low below 45 psia (R-11, R-123), medium 45 to 170 psia (R-12, R-134a, R-500), high 170 to 355 psia (R-22, R-407C, R-410A, R-502), very high above 355 psia (R-13, R-23, R-503).
Question 26
Under the Section 608 definitions, R-134a is used in which kind of appliance?
R-12 and R-134a have a saturation pressure between 45 and 170 psia at 104°F, so their appliances are medium-pressure. Many study guides group them with high-pressure systems for Type II, which covers both.
Question 27
Refrigerant recovered from an appliance and put back into a different owner's equipment must first be:
Recovered refrigerant may go back into the same owner's equipment (often after recycling). If it changes ownership, it must be reclaimed first.
Question 28
Are there any true 'drop-in' replacements for CFC and HCFC refrigerants?
There is no perfect drop-in. Substitutes may need different oil, seals, filter driers or settings.
Question 29
Which lubricant is normally used with HFC refrigerants such as R-134a?
HFCs do not mix well with mineral oil. Polyolester (POE) oils are used with R-134a and R-410A. Alkylbenzene oils are often used with HCFCs.
Question 30
Which lubricant is often used with HCFC refrigerants such as R-22?
R-22 systems traditionally use mineral oil or alkylbenzene. Mixing the wrong oil and refrigerant can cause poor oil return and compressor damage.
Question 31
What is fractionation?
Zeotropic blends (the 400 series, like R-404A or R-407C) can change composition when they leak. That is why blends are charged as a liquid.
Question 32
How should a zeotropic blend (such as R-407C) be charged?
Charging a blend as vapor can leave some components behind in the cylinder. Charge liquid, metered slowly into the low side so it does not slug the compressor.
Question 33
In the refrigeration cycle, where does the refrigerant absorb heat?
Low-pressure liquid boils in the evaporator and absorbs heat from the space being cooled. That is where cooling happens.
Question 34
What leaves the compressor discharge?
The compressor takes in low-pressure vapor and pushes out high-pressure, hot (superheated) vapor to the condenser.
Question 35
What happens to the refrigerant in the condenser?
In the condenser the hot high-pressure vapor rejects heat to air or water and condenses into a high-pressure liquid.
Question 36
What does the metering device (expansion valve) do?
The metering device creates a pressure drop so the liquid can boil at a low temperature in the evaporator.
Question 37
What color is a standard low-side (compound) gauge?
Low side = blue (compound gauge, reads pressure and vacuum). High side = red. The center (utility) hose is usually yellow.
Question 38
What color is a standard high-side gauge and hose?
The red high-side gauge reads pressure only, with a higher range than the blue compound gauge.
Question 39
A compound gauge reads:
The compound (low-side) gauge reads pressure above 0 psig and vacuum in inches of mercury below it.
Question 40
To 'recover' refrigerant means to:
Recover = remove and store, without necessarily testing or processing it.
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