Low GWP Refrigerant Exam Questions
And Answers Practice Questions with
Solutions Newest | Already Graded A+
1. Which of the following refrigerants has the lowest Global Warming
Potential (GWP)?
o a. R-32
o b. R-290
o c. R-410A
o d. R-454B
Answer: b. R-290 (Propane has a GWP of 3; R-744 has a GWP of 1, but that
is not listed as an option).
2. Hydrofluoroolefins (HFOs) are a class of refrigerants known for having:
o a. Zero Ozone Depletion Potential (ODP) and low GWP
o b. High ODP and high GWP
o c. Moderate ODP and moderate GWP
o d. Zero ODP but high GWP
Answer: a. Zero ODP and low GWP
Explanation: Due to their unsaturated chemical structure, HFOs break
down in the atmosphere quickly, giving them a very short atmospheric
lifetime and thus a low GWP. They also contain no chlorine or bromine, so
their ODP is zero.
3. According to ASHRAE Standard 34, the safety classification "A2L" identifies
a refrigerant that is:
o a. Non-toxic and non-flammable
o b. Toxic and highly flammable
o c. Non-toxic and mildly flammable
,o d. Toxic and non-flammable
Answer: c. Non-toxic and mildly flammable
Explanation:
o A: Low toxicity.
o 2L: Mildly flammable (burning velocity < 10 cm/s).
4. When transitioning equipment from a higher-GWP refrigerant to a lower-
GWP alternative like R-454B, it is critical to:
o a. Simply add the new refrigerant to the existing charge.
o b. Remove the old refrigerant, replace critical components (like elastomeric
seals), and pressure test, evacuate, and charge with the new specified
refrigerant.
o c. Reduce the system's operating pressure.
o d. Increase the size of the compressor.
Answer: b. Remove the old refrigerant, replace critical components
(like seals), and properly evacuate and charge with the new
refrigerant.
Explanation: New refrigerants have different chemical properties and often
require different components, lubricants, and seals. A proper system
conversion is mandatory for safety and performance.
5. Which refrigerant is a common low-GWP replacement for R-134a in
automotive air conditioning systems?
o a. R-1234yf
o b. R-22
o c. R-410A
o d. R-404A
Answer: a. R-1234yf
Explanation: R-1234yf (an HFO) was developed specifically as a low-GWP
replacement for R-134a in mobile A/C systems.
,6. According to the EPA's SNAP program, what is the GWP threshold below
which a refrigerant is generally considered "low-GWP"?
o a. 100
o b. 500
o c. 750
o d. 1500
Answer: c. 750
Explanation: The EPA's Significant New Alternatives Policy (SNAP) program
often uses a GWP of 750 as a benchmark for identifying lower-GWP
alternatives, especially in new equipment.
7. Why are HFO refrigerants generally less flammable than hydrocarbon
refrigerants (HCs)?
o a. They have a higher boiling point.
o b. They contain chlorine.
o c. Their chemical composition, specifically the presence of fluorine,
increases stability.
o d. They operate at lower pressures.
Answer: c. Their chemical composition, specifically the presence of
fluorine, increases stability.
Explanation: The fluorine atoms in HFO molecules help to quench the
combustion reaction, making them less flammable.
8. An example of a refrigerant with a GWP of "1" is:
o a. R-32
o b. R-134a
o c. R-744 (Carbon Dioxide)
o d. R-410A
Answer: c. R-744
Explanation: Carbon Dioxide (R-744) has a GWP of 1 by definition and is
used as the baseline for all GWP measurements.
, 9. Which of the following is an HFO refrigerant?
o a. R-134a
o b. R-22
o c. R-1234ze
o d. R-290
Answer: c. R-1234ze
Explanation: R-1234ze is a common HFO. R-134a is an HFC, R-22 is an
HCFC, and R-290 (propane) is a hydrocarbon.
10. What is the primary reason for a rapid global phase-down of high-
GWP HFCs?
o a. Their significant contribution to stratospheric ozone depletion.
o b. Their high flammability risk.
o c. Their potential to cause severe frostbite.
o d. Their high Global Warming Potential and impact on climate change.
Answer: d. Their high GWP and impact on climate change.
Explanation: The Kigali Amendment to the Montreal Protocol addresses
the phase-down of HFCs because of their high GWP, even though they do
not deplete the ozone layer.
11. What is "retrofit" generally defined as in the context of refrigerants?
o a. Repairing a leak in an existing system.
o b. Converting an existing system designed for one refrigerant to use a
different refrigerant.
o c. Installing a brand new system.
o d. Disposing of an old system.
Answer: b. Converting an existing system designed for one refrigerant
to use a different refrigerant.
12. The global agreement to phase down the production and
consumption of HFCs is known as the:
And Answers Practice Questions with
Solutions Newest | Already Graded A+
1. Which of the following refrigerants has the lowest Global Warming
Potential (GWP)?
o a. R-32
o b. R-290
o c. R-410A
o d. R-454B
Answer: b. R-290 (Propane has a GWP of 3; R-744 has a GWP of 1, but that
is not listed as an option).
2. Hydrofluoroolefins (HFOs) are a class of refrigerants known for having:
o a. Zero Ozone Depletion Potential (ODP) and low GWP
o b. High ODP and high GWP
o c. Moderate ODP and moderate GWP
o d. Zero ODP but high GWP
Answer: a. Zero ODP and low GWP
Explanation: Due to their unsaturated chemical structure, HFOs break
down in the atmosphere quickly, giving them a very short atmospheric
lifetime and thus a low GWP. They also contain no chlorine or bromine, so
their ODP is zero.
3. According to ASHRAE Standard 34, the safety classification "A2L" identifies
a refrigerant that is:
o a. Non-toxic and non-flammable
o b. Toxic and highly flammable
o c. Non-toxic and mildly flammable
,o d. Toxic and non-flammable
Answer: c. Non-toxic and mildly flammable
Explanation:
o A: Low toxicity.
o 2L: Mildly flammable (burning velocity < 10 cm/s).
4. When transitioning equipment from a higher-GWP refrigerant to a lower-
GWP alternative like R-454B, it is critical to:
o a. Simply add the new refrigerant to the existing charge.
o b. Remove the old refrigerant, replace critical components (like elastomeric
seals), and pressure test, evacuate, and charge with the new specified
refrigerant.
o c. Reduce the system's operating pressure.
o d. Increase the size of the compressor.
Answer: b. Remove the old refrigerant, replace critical components
(like seals), and properly evacuate and charge with the new
refrigerant.
Explanation: New refrigerants have different chemical properties and often
require different components, lubricants, and seals. A proper system
conversion is mandatory for safety and performance.
5. Which refrigerant is a common low-GWP replacement for R-134a in
automotive air conditioning systems?
o a. R-1234yf
o b. R-22
o c. R-410A
o d. R-404A
Answer: a. R-1234yf
Explanation: R-1234yf (an HFO) was developed specifically as a low-GWP
replacement for R-134a in mobile A/C systems.
,6. According to the EPA's SNAP program, what is the GWP threshold below
which a refrigerant is generally considered "low-GWP"?
o a. 100
o b. 500
o c. 750
o d. 1500
Answer: c. 750
Explanation: The EPA's Significant New Alternatives Policy (SNAP) program
often uses a GWP of 750 as a benchmark for identifying lower-GWP
alternatives, especially in new equipment.
7. Why are HFO refrigerants generally less flammable than hydrocarbon
refrigerants (HCs)?
o a. They have a higher boiling point.
o b. They contain chlorine.
o c. Their chemical composition, specifically the presence of fluorine,
increases stability.
o d. They operate at lower pressures.
Answer: c. Their chemical composition, specifically the presence of
fluorine, increases stability.
Explanation: The fluorine atoms in HFO molecules help to quench the
combustion reaction, making them less flammable.
8. An example of a refrigerant with a GWP of "1" is:
o a. R-32
o b. R-134a
o c. R-744 (Carbon Dioxide)
o d. R-410A
Answer: c. R-744
Explanation: Carbon Dioxide (R-744) has a GWP of 1 by definition and is
used as the baseline for all GWP measurements.
, 9. Which of the following is an HFO refrigerant?
o a. R-134a
o b. R-22
o c. R-1234ze
o d. R-290
Answer: c. R-1234ze
Explanation: R-1234ze is a common HFO. R-134a is an HFC, R-22 is an
HCFC, and R-290 (propane) is a hydrocarbon.
10. What is the primary reason for a rapid global phase-down of high-
GWP HFCs?
o a. Their significant contribution to stratospheric ozone depletion.
o b. Their high flammability risk.
o c. Their potential to cause severe frostbite.
o d. Their high Global Warming Potential and impact on climate change.
Answer: d. Their high GWP and impact on climate change.
Explanation: The Kigali Amendment to the Montreal Protocol addresses
the phase-down of HFCs because of their high GWP, even though they do
not deplete the ozone layer.
11. What is "retrofit" generally defined as in the context of refrigerants?
o a. Repairing a leak in an existing system.
o b. Converting an existing system designed for one refrigerant to use a
different refrigerant.
o c. Installing a brand new system.
o d. Disposing of an old system.
Answer: b. Converting an existing system designed for one refrigerant
to use a different refrigerant.
12. The global agreement to phase down the production and
consumption of HFCs is known as the:
