In which of the following ways does ozone depletion affect humans? (Select all that apply)

Increased risk of heart disease

Increased risk of pancreatic cancer

Which of the following statements about fractionation of refrigerants is true? (select all that apply)

Is when refrigerants settle into layers

EPA 608 Core Practice Test

The EPA 608 Core practice test on this page is a free 50-question bank for the section every candidate must pass first. Each attempt draws 25 questions, the length of the real Core section, on ozone science and the Clean Air Act venting law, the three R's, cylinder safety, refrigerant families, and recovery and evacuation levels, graded instantly with a plain-English explanation under every answer. Technicians search for this test as the EPA core practice exam or the EPA core test. No signup. The pass mark is 18 of 25 (72%).

Start the test Skip to: what the exam covers · why Core is required for every Type · refrigerant families · evacuation levels · FAQ

50 free Core practice questions with instant scoring

The 50 EPA 608 Core practice questions below are drawn 25 at a time, scored instantly, and explained with the rule each answer comes from.

1. Once you pass the EPA exam, the regulations you learned will never change. (True or false)
2. Ground level ozone is what absorbs and reflects harmful UV rays from the sun. (True or false)
3. The majority of ozone is located in the Troposphere. (True or false)
4. If a refrigerant has a drop in replacement, then no retrofit is needed. (True or false)
5. In a zeotropic blend, all refrigerants have the same boiling point. (True or false)
6. R-407c is an azeotropic blend. (True or false)
7. In which of the following ways does ozone depletion affect humans? (Select all that apply)
8. Which of the following statements about fractionation of refrigerants is true? (select all that apply)
9. Alkylbenzene (AB) oil is used for systems with which of the following refrigerants? (Select all that apply)
10. B2 refrigerants are more dangerous than which of the following? (Select all that apply)
11. Which of the following elements do CFCs contain? (Select all that apply)
12. Other than fluorine and chlorine, what do HCFCs contain? (Select all that apply)
13. Which of the following elements can be found in HCFCs? (Select all that apply)
14. Other than hydrogen, which of the following molecules do HFCs contain? (Select all that apply)
15. As environmental technicians, we must be up to date with which types of laws?
16. For the EPA 608 Universal Certification, how many questions will you receive?
17. If you need to get Type III certification, which of the following will be on your exam?
18. Which of the following is a common way that leaks can occur?
19. Which of the following is least likely to be a common leak location in HVAC systems?
20. Which of the following is not a reason why refrigerant leaks are a concern?
21. Do natural events like volcanic eruptions contribute to chlorine in the stratosphere?
22. Is there evidence that refrigerants are in the stratosphere?
23. Which of the following statements is TRUE about chlorine?
24. Ozone has __ atoms of oxygen.
25. How many molecules of ozone can three chlorine atoms destroy?
26. What is the major function of ozone in the stratosphere?
27. What is the primary source of chlorine in the Stratosphere?
28. Which element is primarily responsible for stratospheric ozone depletion?
29. Which of the following are effects of ozone depletion?
30. Which refrigerant chemicals are responsible for the destruction of the ozone layer?
31. Who does ozone depletion affect?
32. What is temperature glide?
33. What is bubble point?
34. What is the definition of dew point?
35. A manufacturer lists a refrigerant mixture with R-32 (23%), R-125 (25%), and R-134a (52%). How is this blend classified?
36. Which of the following is considered retrofitting?
37. Which of the following are reasons to not mix your own refrigerants?
38. A bottle of hygroscopic refrigerant oil is left uncapped on a humid day and then used in a system. What problem is most likely to show up first?
39. If we are retrofitting a system to use R-134a, which oil do we need to use?
40. B2 refrigerants are safer than which one of the following?
41. What does CFC stand for?
42. What does HCFC stand for?
43. What does HFC stand for?
44. Which of the following atoms is part of an HFC molecule?
45. What safety classification do HFO refrigerants typically fall under?
46. What does HFO stand for?
47. Which of the following do HFOs contain?
48. Which statement is true about hydrocarbons?
49. R-410A has a GWP of about 2,088. What does this number mean?
50. Which one of the following refrigerants has the lowest global warming potential (GWP)?

What the Core exam covers

The EPA 608 Core exam is 25 multiple choice questions on the rules that apply to every system: Section 608 of the Clean Air Act, ozone science, the three R's (recovery, recycling, reclamation), evacuation levels, cylinder safety, and dehydration. Core is shared by Type 1, 2, 3 (Type I, II, III in older material) and Universal; older job postings call it the CFC certification test.

194 of the 461 practice exams our users completed (app data as of August 2026) in the EPA 608 Practice Test app are Core runs, averaging just under seven minutes for 25 questions. The 50 questions here come from the same 604-question bank, verified against 40 CFR Part 82.

Ozone depletion, the Montreal Protocol, and the Clean Air Act

Section 608 of the Clean Air Act prohibits venting refrigerants that harm the stratospheric ozone layer (40 CFR §82.154). Chlorine from CFCs and HCFCs breaks apart ozone (O₃); HFCs contain no chlorine, so their ODP is zero. The exam asks Ozone Depletion Potential (ODP) and Global Warming Potential (GWP) by family, the 1987 Montreal Protocol and 1990 Clean Air Act Amendments that set the CFC and HCFC phase-outs, and the 2020 AIM Act that phases down HFCs.

Recovery, recycling, and reclamation: three legal terms

Recovery removes refrigerant into an external container. Recycling cleans it for reuse on site. Reclamation processes it to the AHRI 700 purity standard (formerly ARI 700) at an EPA-approved reclaimer. Recovered or recycled refrigerant may return to equipment of the same owner; refrigerant that changes ownership must be reclaimed first.

Safety: toxicity classes, oxygen deprivation, heat, and pressure testing

Under ASHRAE Standard 34 the letter is toxicity (A lower, B higher) and the number is flammability (1, 2L, 2, 3); R-134a is A1. Refrigerant vapor is heavier than air and displaces oxygen in low or confined spaces. Never heat a cylinder above 125°F, never expose refrigerant to an open flame (it forms hydrochloric and hydrofluoric acid and phosgene), and pressure test with dry nitrogen through a regulator, never oxygen or compressed air.

Venting penalties, leak rates, service records, and the sales restriction

Venting CFC and HCFC refrigerants has been illegal since July 1, 1992, and HFC and PFC substitutes since November 15, 1995. Civil penalties run up to $69,733 per day per violation (40 CFR §82.34, 2025 adjustment). Service records must be kept 3 years. Leak rate thresholds for appliances holding 50 pounds or more are 10% comfort cooling, 20% commercial refrigeration, and 30% industrial process refrigeration; the EPA 608 Type 2 practice test drills them. Since November 14, 1994, refrigerant sales are restricted to certified technicians. Section 609 covers motor vehicle air conditioning only and does not substitute for any 608 type (EPA 608 vs 609).

Refrigerant families: CFC, HCFC, HFC, HFO

CFC, HCFC, HFC, and HFO are the four refrigerant generations the exam separates by ODP and GWP. CFC is chlorine, fluorine, carbon; HCFC adds hydrogen, so it breaks down faster and has a lower ODP; HFC has no chlorine; HFO is an HFC with a carbon double bond, a short atmospheric life, and a single-digit GWP. HFCs have zero ODP but high GWP, which is why the AIM Act phases them down.

R-22 production ended January 1, 2020. Technicians can still recover and recycle existing R-22 (HCFC), but no new production is permitted in the U.S.

ODP, GWP, and 2026 status by family.

Family	Example	ODP	GWP	Status (2026)
CFC	R-11, R-12	High (1.0)	High	Fully phased out
HCFC	R-22, R-123	Low (0.055)	Moderate	Production ended 2020
HFC	R-410A, R-134a	Zero	High (2,088)	AIM Act phase down in progress
HFO	R-1234yf	Zero	Very Low (4)	Current transition target

Recovery methods, evacuation levels, and cylinders

Recovery on the Core exam means two methods plus the evacuation level and cylinder rules that go with each; the cheat sheet in the EPA 608 study guide collects every number.

The two recovery methods. EPA 608 recognizes exactly two methods of refrigerant recovery, not three:

System dependent (passive) recovery, equipment that requires the appliance's own components (such as its compressor) to push the refrigerant out. Used mainly on small appliances (5 lbs or less), the equipment the EPA 608 Type 1 practice test covers.
Self contained (active) recovery, equipment that pulls the refrigerant out on its own, without help from the appliance. Required for larger and high pressure systems.

Small appliances: how much you must recover

Small appliance recovery must capture 90% of the charge with the compressor operating, 80% with the compressor not operating, or pull the appliance to 4 inches of mercury vacuum, when the recovery equipment was made on or after November 15, 1993. Recovery equipment made before November 15, 1993 is held to 80% whether the compressor runs or not. The same three numbers apply on the Type 1 section.

Required evacuation levels for larger appliances

Larger appliances must be evacuated to between 0 and 15 in. Hg vacuum, or to 25 mm Hg absolute for low pressure systems, before opening or disposal. 40 CFR §82.156 sets the level by appliance type and by whether the recovery equipment was made before or on/after November 15, 1993:

Appliance type	Equip. before Nov 15, 1993	Equip. on/after Nov 15, 1993
HCFC-22 (or similar), under 200 lbs	0 in. Hg	0 in. Hg
HCFC-22 (or similar), 200 lbs or more	4 in. Hg	10 in. Hg
Other high pressure (CFC-12, -500, -114), under 200 lbs	4 in. Hg	10 in. Hg
Other high pressure (CFC-12, -500, -114), 200 lbs or more	4 in. Hg	15 in. Hg
Very high pressure (CFC-13, -503)	0 in. Hg	0 in. Hg
Low pressure (CFC-11, HCFC-123)	25 mm Hg absolute	25 mm Hg absolute

Low pressure appliances (R-11, R-123) require 25 mm Hg absolute; the EPA 608 Type 3 practice test covers those chillers.

Recovery cylinder rules

Recovery cylinders on the Core exam follow three rules: fill level, DOT approval, and color.

Never fill a recovery cylinder above 80% of capacity, so the liquid has room to expand.
Use a DOT-approved recovery cylinder.
Recovery cylinders carry a gray body with a yellow top (the DOT/industry color code).

Passing the Core section

Core passes at 72%, 18 of 25, on the proctored exam. The open book mail-in option some organizations offer for Core and Type 1 sets the pass mark at 84%, and an open book Core cannot be used toward Universal certification. Core certification never expires. The EPA 608 test page explains scoring for every section, and the EPA 608 Core study guide covers venting dates, penalty amounts, the de minimis exemption, and the recovery-to-reclamation lifecycle.

Core is required for every Type: the sitting, providers, and fees

Passing Core first is required for every EPA 608 certification (40 CFR §82.161); Core plus at least one Type earns the card, and sections are scored separately. The exam is closed book and proctored, in person or online; the EPA 608 certification online guide compares approved providers. Core plus all three Types is Universal, the format the EPA 608 Universal practice test simulates; fees are on the EPA 608 certification cost page.

EPA 608 Core practice test FAQ

What is the passing score for the EPA 608 Core exam?

72%, which is 18 out of 25 correct answers. The official proctored exam is administered closed book by EPA-approved organizations such as ESCO Institute and Mainstream Engineering.

Is this Core practice test free?

Yes. All 50 Core questions on this page are free with instant scoring and explanations, no signup. A free account saves scores and unlocks all 604 verified questions; Pro ($14.99 lifetime) adds AI Tutor and timed simulation.

What is the difference between the Core exam and Type 1, 2, and 3?

Core covers the rules every technician needs: venting law, recovery and reclamation, refrigerant families, and safety. Type 1, 2, and 3 add equipment-specific knowledge. Certification needs Core plus one Type; all four earn Universal. See the EPA 608 practice test.

Can I retake the EPA 608 Core exam if I fail?

Yes. Every EPA-approved testing organization lets you retest Core, usually for a retake fee and sometimes after a short wait. Sections are scored separately, so you retake only the section you failed, not the whole exam.