EPA 608 Universal Certification (Core)
Exam study guide COMPLETE EXAM
Newest 2026 Complete Questions and
Correct Detailed Answers (Verified
Answers) |Already Graded A+
Chapter 5 – Small Appliances, Refrigerant Recovery & EPA Certification
Question 41
Ozone depletion is caused by _______ in HFC refrigerants.
Correct Answer: Chlorine
Rationale:
Chlorine atoms released from ozone-depleting refrigerants react with ozone molecules in the
stratosphere, destroying them. Note: In current EPA terminology, HFC refrigerants do not
contain chlorine and have zero ozone depletion potential. If this question appears exactly this
way in your source, preserve it for revision, but be aware that the technically correct statement
is that chlorine in CFCs and HCFCs causes ozone depletion.
Exam Tip:
Remember: CFCs and HCFCs contain chlorine; HFCs do not.
Question 42
CFCs and HCFCs ________ making them capable of reaching the stratospheric ozone layer.
Correct Answer: Do not dissolve in water or easily break down in the atmosphere.
Rationale:
CFCs and HCFCs are chemically stable in the lower atmosphere. Because they resist
decomposition, they eventually reach the stratosphere, where ultraviolet radiation breaks them
apart and releases chlorine atoms that destroy ozone.
, Exam Tip:
Stable molecules = Reach the stratosphere.
Question 43
According to the Rowland-Molina theory, ________ are destroyed by each chlorine atom in
the stratosphere.
Correct Answer: 100,000 ozone molecules
Rationale:
The Rowland-Molina theory explains that a single chlorine atom acts as a catalyst, repeatedly
destroying ozone molecules before it is removed from the atmosphere.
Exam Tip:
One chlorine atom = About 100,000 ozone molecules destroyed.
Question 44
The stratospheric ozone layer protects us from _______.
Correct Answer: Ultraviolet radiation from the sun
Rationale:
The ozone layer absorbs most harmful UV-B radiation, protecting people, animals, and
ecosystems from excessive ultraviolet exposure.
Question 45
Which health effect increases from loss of the stratospheric ozone layer?
Correct Answer: Cases of cataracts or skin cancer
Rationale:
As ozone depletion allows more ultraviolet radiation to reach Earth's surface, the risks of skin
cancer, cataracts, and immune system damage increase.
Question 46
,What proves that HCFCs are in the stratosphere?
Correct Answer: HCFCs found in air samples from the stratosphere.
Rationale:
Scientific air sampling confirms that HCFC molecules reach the stratosphere, where they can
contribute to ozone depletion.
Question 47
What makes HFC refrigerants damaging to the environment?
Correct Answer: They can have very high global warming potentials.
Rationale:
Although HFC refrigerants do not damage the ozone layer, many have high Global Warming
Potentials (GWPs), meaning they can contribute significantly to climate change if released.
Question 48
_______ makes HFO refrigerants less flammable than HC refrigerants.
Correct Answer: Fluorine
Rationale:
The presence of fluorine in HFO refrigerants reduces their flammability compared with
hydrocarbon refrigerants while maintaining good refrigeration performance.
Question 49
Which refrigerant contains chlorine?
Correct Answer: R-12
Rationale:
R-12 is a CFC refrigerant that contains chlorine, which contributes to ozone depletion when
released into the atmosphere.
Question 50
, HFO refrigerants are miscible in _______ lubricants.
Correct Answer: POE lubricants
Rationale:
Most HFO refrigerants are compatible with Polyol Ester (POE) lubricants, which provide effective
lubrication and proper refrigerant circulation.
Chapter 6 – Refrigerants, Lubricants & EPA Regulations
Question 51
An example of HCFC refrigerant is: ______
Correct Answer: R-123
Rationale:
R-123 is a Hydrochlorofluorocarbon (HCFC) refrigerant. HCFC refrigerants contain hydrogen,
chlorine, fluorine, and carbon. Although they have a lower ozone depletion potential than CFCs,
they still contribute to ozone depletion and are being phased out under international
environmental agreements.
Exam Tip:
Remember:
• CFC: R-12
• HCFC: R-22, R-123
• HFC: R-134a, R-410A
• HFO: R-1234yf
Question 52
What is being done in the U.S. to stop damage to the stratospheric ozone layer?
Correct Answer: Eliminating the use of CFC and HCFC refrigerants
Rationale:
The United States, through the EPA and the Montreal Protocol, is phasing out ozone-depleting
refrigerants such as CFCs and HCFCs while encouraging the use of environmentally safer
alternatives.
Exam study guide COMPLETE EXAM
Newest 2026 Complete Questions and
Correct Detailed Answers (Verified
Answers) |Already Graded A+
Chapter 5 – Small Appliances, Refrigerant Recovery & EPA Certification
Question 41
Ozone depletion is caused by _______ in HFC refrigerants.
Correct Answer: Chlorine
Rationale:
Chlorine atoms released from ozone-depleting refrigerants react with ozone molecules in the
stratosphere, destroying them. Note: In current EPA terminology, HFC refrigerants do not
contain chlorine and have zero ozone depletion potential. If this question appears exactly this
way in your source, preserve it for revision, but be aware that the technically correct statement
is that chlorine in CFCs and HCFCs causes ozone depletion.
Exam Tip:
Remember: CFCs and HCFCs contain chlorine; HFCs do not.
Question 42
CFCs and HCFCs ________ making them capable of reaching the stratospheric ozone layer.
Correct Answer: Do not dissolve in water or easily break down in the atmosphere.
Rationale:
CFCs and HCFCs are chemically stable in the lower atmosphere. Because they resist
decomposition, they eventually reach the stratosphere, where ultraviolet radiation breaks them
apart and releases chlorine atoms that destroy ozone.
, Exam Tip:
Stable molecules = Reach the stratosphere.
Question 43
According to the Rowland-Molina theory, ________ are destroyed by each chlorine atom in
the stratosphere.
Correct Answer: 100,000 ozone molecules
Rationale:
The Rowland-Molina theory explains that a single chlorine atom acts as a catalyst, repeatedly
destroying ozone molecules before it is removed from the atmosphere.
Exam Tip:
One chlorine atom = About 100,000 ozone molecules destroyed.
Question 44
The stratospheric ozone layer protects us from _______.
Correct Answer: Ultraviolet radiation from the sun
Rationale:
The ozone layer absorbs most harmful UV-B radiation, protecting people, animals, and
ecosystems from excessive ultraviolet exposure.
Question 45
Which health effect increases from loss of the stratospheric ozone layer?
Correct Answer: Cases of cataracts or skin cancer
Rationale:
As ozone depletion allows more ultraviolet radiation to reach Earth's surface, the risks of skin
cancer, cataracts, and immune system damage increase.
Question 46
,What proves that HCFCs are in the stratosphere?
Correct Answer: HCFCs found in air samples from the stratosphere.
Rationale:
Scientific air sampling confirms that HCFC molecules reach the stratosphere, where they can
contribute to ozone depletion.
Question 47
What makes HFC refrigerants damaging to the environment?
Correct Answer: They can have very high global warming potentials.
Rationale:
Although HFC refrigerants do not damage the ozone layer, many have high Global Warming
Potentials (GWPs), meaning they can contribute significantly to climate change if released.
Question 48
_______ makes HFO refrigerants less flammable than HC refrigerants.
Correct Answer: Fluorine
Rationale:
The presence of fluorine in HFO refrigerants reduces their flammability compared with
hydrocarbon refrigerants while maintaining good refrigeration performance.
Question 49
Which refrigerant contains chlorine?
Correct Answer: R-12
Rationale:
R-12 is a CFC refrigerant that contains chlorine, which contributes to ozone depletion when
released into the atmosphere.
Question 50
, HFO refrigerants are miscible in _______ lubricants.
Correct Answer: POE lubricants
Rationale:
Most HFO refrigerants are compatible with Polyol Ester (POE) lubricants, which provide effective
lubrication and proper refrigerant circulation.
Chapter 6 – Refrigerants, Lubricants & EPA Regulations
Question 51
An example of HCFC refrigerant is: ______
Correct Answer: R-123
Rationale:
R-123 is a Hydrochlorofluorocarbon (HCFC) refrigerant. HCFC refrigerants contain hydrogen,
chlorine, fluorine, and carbon. Although they have a lower ozone depletion potential than CFCs,
they still contribute to ozone depletion and are being phased out under international
environmental agreements.
Exam Tip:
Remember:
• CFC: R-12
• HCFC: R-22, R-123
• HFC: R-134a, R-410A
• HFO: R-1234yf
Question 52
What is being done in the U.S. to stop damage to the stratospheric ozone layer?
Correct Answer: Eliminating the use of CFC and HCFC refrigerants
Rationale:
The United States, through the EPA and the Montreal Protocol, is phasing out ozone-depleting
refrigerants such as CFCs and HCFCs while encouraging the use of environmentally safer
alternatives.
