Master the 2026 EPA 608 & 609 Certification
Exams: Free Full-Length Practice Test with
95 Questions & Expert Explanations | CFC,
HFC, ODP, GWP & Clean Air Act Prep
Description:
Ace your 2026/2027 EPA 608 (Core, Type I-III) and 609 (MVAC) certification exams with our
comprehensive study guide. This full-length practice test features 95 challenging questions on
refrigerant types (CFC, HCFC, HFC), Ozone Depletion Potential (ODP), Global Warming
Potential (GWP), Clean Air Act regulations, safe recovery procedures, and atmospheric
science. Get detailed answer explanations, learn current AHRI 700 & SAE standards, and
identify key topics for HVAC/R technicians.
Pass with confidence on your first try – Download Your Free Ultimate Prep Guide Now!
, 2026/2027 EPA 608/609 Certification Practice Exam
Section 1: Atmospheric Science & Ozone Depletion
1. Ozone present in the stratosphere and at ground level can both be classified as harmful
pollutants.
A. True
B. False
Answer: B. False
Explanation: Stratospheric ozone forms a protective layer that absorbs harmful ultraviolet (UV)
radiation and is beneficial. Ground-level ozone, a key component of smog, is a harmful pollutant
that impacts respiratory health and the environment.
2. For determining the Ozone Depletion Potential (ODP), which compound has been assigned a
baseline value of 1?
A. CFC-12
B. HCFC-22
C. CFC-11
D. HFC-134a
Answer: C. CFC-11
Explanation: CFC-11 (trichlorofluoromethane) is used as the reference point for ODP
calculations. All other ozone-depleting substances are rated relative to its potency, which is
defined as 1.0.
3. The stratospheric ozone layer primarily absorbs and scatters which form of solar radiation?
A. Infrared radiation
B. Visible light
C. Ultraviolet (UV) light
D. Microwave radiation
, Answer: C. Ultraviolet (UV) light
Explanation: The ozone layer filters out the majority of the sun's biologically harmful
ultraviolet (UV-B and UV-C) radiation, protecting living organisms on Earth.
4. A single chlorine atom released in the stratosphere has the potential to destroy how many
ozone molecules?
A. 10
B. 1,000
C. 10,000
D. 100,000
Answer: D. 100,000
Explanation: Chlorine acts as a catalyst in the ozone destruction cycle. One chlorine atom can
initiate a chain reaction, destroying approximately 100,000 ozone molecules before being
deactivated.
5. The primary chemical agent responsible for stratospheric ozone depletion is:
A. Carbon Dioxide (CO2)
B. Chlorine Monoxide (ClO)
C. Methane (CH4)
D. Water Vapor (H2O)
Answer: B. Chlorine Monoxide (ClO)
Explanation: Chlorine monoxide is a key intermediate compound in the catalytic cycle that
breaks down ozone. Its presence is a direct indicator of ozone depletion activity.
6. The "ozone hole" is most prominently observed annually over which region?
A. The Arctic
B. Antarctica
C. The Equator
D. North America
, Answer: B. Antarctica
Explanation: Severe seasonal ozone depletion, commonly called the "ozone hole," occurs over
Antarctica due to unique atmospheric conditions involving polar stratospheric clouds that
accelerate chlorine-driven ozone destruction.
7. Ozone molecules in the stratosphere are formed when UV light strikes:
A. Nitrogen molecules (N2)
B. Carbon Dioxide molecules (CO2)
C. Oxygen molecules (O2)
D. Water Vapor molecules (H2O)
Answer: C. Oxygen molecules (O2)
Explanation: High-energy UV-C radiation breaks apart molecular oxygen (O2) into two free
oxygen atoms. These atoms then combine with other O2 molecules to form ozone (O3).
8. Which element in a refrigerant molecule generally increases its chemical stability in the lower
atmosphere, allowing it to reach the stratosphere?
A. Hydrogen
B. Fluorine
C. Chlorine
D. Carbon
Answer: C. Chlorine
Explanation: Refrigerants containing chlorine but no hydrogen (like CFCs) are highly stable in
the troposphere. This longevity allows them to migrate to the stratosphere where UV radiation
breaks them apart, releasing chlorine atoms.
9. Which of the following will NOT directly react with and destroy stratospheric ozone?
A. Chlorine (Cl)
B. Bromine (Br)
C. Fluorine (F)
Exams: Free Full-Length Practice Test with
95 Questions & Expert Explanations | CFC,
HFC, ODP, GWP & Clean Air Act Prep
Description:
Ace your 2026/2027 EPA 608 (Core, Type I-III) and 609 (MVAC) certification exams with our
comprehensive study guide. This full-length practice test features 95 challenging questions on
refrigerant types (CFC, HCFC, HFC), Ozone Depletion Potential (ODP), Global Warming
Potential (GWP), Clean Air Act regulations, safe recovery procedures, and atmospheric
science. Get detailed answer explanations, learn current AHRI 700 & SAE standards, and
identify key topics for HVAC/R technicians.
Pass with confidence on your first try – Download Your Free Ultimate Prep Guide Now!
, 2026/2027 EPA 608/609 Certification Practice Exam
Section 1: Atmospheric Science & Ozone Depletion
1. Ozone present in the stratosphere and at ground level can both be classified as harmful
pollutants.
A. True
B. False
Answer: B. False
Explanation: Stratospheric ozone forms a protective layer that absorbs harmful ultraviolet (UV)
radiation and is beneficial. Ground-level ozone, a key component of smog, is a harmful pollutant
that impacts respiratory health and the environment.
2. For determining the Ozone Depletion Potential (ODP), which compound has been assigned a
baseline value of 1?
A. CFC-12
B. HCFC-22
C. CFC-11
D. HFC-134a
Answer: C. CFC-11
Explanation: CFC-11 (trichlorofluoromethane) is used as the reference point for ODP
calculations. All other ozone-depleting substances are rated relative to its potency, which is
defined as 1.0.
3. The stratospheric ozone layer primarily absorbs and scatters which form of solar radiation?
A. Infrared radiation
B. Visible light
C. Ultraviolet (UV) light
D. Microwave radiation
, Answer: C. Ultraviolet (UV) light
Explanation: The ozone layer filters out the majority of the sun's biologically harmful
ultraviolet (UV-B and UV-C) radiation, protecting living organisms on Earth.
4. A single chlorine atom released in the stratosphere has the potential to destroy how many
ozone molecules?
A. 10
B. 1,000
C. 10,000
D. 100,000
Answer: D. 100,000
Explanation: Chlorine acts as a catalyst in the ozone destruction cycle. One chlorine atom can
initiate a chain reaction, destroying approximately 100,000 ozone molecules before being
deactivated.
5. The primary chemical agent responsible for stratospheric ozone depletion is:
A. Carbon Dioxide (CO2)
B. Chlorine Monoxide (ClO)
C. Methane (CH4)
D. Water Vapor (H2O)
Answer: B. Chlorine Monoxide (ClO)
Explanation: Chlorine monoxide is a key intermediate compound in the catalytic cycle that
breaks down ozone. Its presence is a direct indicator of ozone depletion activity.
6. The "ozone hole" is most prominently observed annually over which region?
A. The Arctic
B. Antarctica
C. The Equator
D. North America
, Answer: B. Antarctica
Explanation: Severe seasonal ozone depletion, commonly called the "ozone hole," occurs over
Antarctica due to unique atmospheric conditions involving polar stratospheric clouds that
accelerate chlorine-driven ozone destruction.
7. Ozone molecules in the stratosphere are formed when UV light strikes:
A. Nitrogen molecules (N2)
B. Carbon Dioxide molecules (CO2)
C. Oxygen molecules (O2)
D. Water Vapor molecules (H2O)
Answer: C. Oxygen molecules (O2)
Explanation: High-energy UV-C radiation breaks apart molecular oxygen (O2) into two free
oxygen atoms. These atoms then combine with other O2 molecules to form ozone (O3).
8. Which element in a refrigerant molecule generally increases its chemical stability in the lower
atmosphere, allowing it to reach the stratosphere?
A. Hydrogen
B. Fluorine
C. Chlorine
D. Carbon
Answer: C. Chlorine
Explanation: Refrigerants containing chlorine but no hydrogen (like CFCs) are highly stable in
the troposphere. This longevity allows them to migrate to the stratosphere where UV radiation
breaks them apart, releasing chlorine atoms.
9. Which of the following will NOT directly react with and destroy stratospheric ozone?
A. Chlorine (Cl)
B. Bromine (Br)
C. Fluorine (F)
