ALBERTA PLUMBER APPRENTICESHIP
Practice Exam Questions and Correct Answers
(Verified Answers) Plus Rationales 2026
1. What is the maximum allowable temperature for domestic hot
water supplied to a fixture?
A. 45°C
B. 55°C
C. 60°C
D. 70°C
This prevents scalding while maintaining effective bacterial
control.
2. When joining PVC pipes, the primer is used to:
A. Seal the pipe
B. Clean and soften the surface for solvent cement
C. Lubricate the fitting
D. Protect against corrosion
Primer ensures the solvent cement properly fuses the pipe and
fitting.
3. The term "backflow" refers to:
A. Water leaking from a pipe
B. Water flowing in the opposite direction, potentially
contaminating potable water
C. Water pressure fluctuations
D. Air entering the water system
Backflow can introduce contaminants into a drinking water
system, so prevention devices are critical.
4. Which of the following is a common backflow prevention
device?
, A. Ball valve
B. Check valve
C. Double check valve assembly (DCVA)
D. Gate valve
DCVAs prevent water from flowing back into the potable water
system under normal conditions.
5. The minimum size of a water service line for a single-family
dwelling is usually:
A. 15 mm
B. 20 mm
C. 25 mm
D. 40 mm
This ensures adequate flow and pressure for typical residential
fixtures.
6. What is the purpose of a pressure-reducing valve (PRV)?
A. Increase pressure
B. Reduce excessive incoming water pressure to safe levels
C. Control water temperature
D. Prevent backflow
High pressure can damage plumbing; PRVs protect pipes and
fixtures.
7. What is the standard pipe material for underground drainage in
Alberta?
A. Copper
B. Galvanized steel
C. PVC
D. PEX
PVC is durable, corrosion-resistant, and easy to install for
underground drainage.
8. When installing a water heater, the expansion tank is
, required to:
A. Heat water faster
B. Absorb excess pressure caused by thermal expansion
C. Filter impurities
D. Reduce noise
Thermal expansion in closed systems increases pressure; the
expansion tank prevents damage.
9. Which of the following is NOT allowed in a potable water
system?
A. Copper pipe
B. PEX tubing
C. Lead pipe
D. CPVC
Lead is banned in potable water systems due to its toxicity.
10. A P-trap must have a minimum water seal depth of:
A. 1/2 inch
B. 1 inch
C. 2 inches
D. 3 inches
A 2-inch water seal is sufficient to prevent sewer gases while
allowing smooth drainage.
11. In plumbing, what is a “cleanout”?
A. A type of vent
B. An access point for clearing blockages in a drain line
C. A pressure relief device
D. A type of faucet
Cleanouts provide convenient access to drain lines for
maintenance and unclogging.
12. Which method is recommended to test a new plumbing
installation for leaks?
Practice Exam Questions and Correct Answers
(Verified Answers) Plus Rationales 2026
1. What is the maximum allowable temperature for domestic hot
water supplied to a fixture?
A. 45°C
B. 55°C
C. 60°C
D. 70°C
This prevents scalding while maintaining effective bacterial
control.
2. When joining PVC pipes, the primer is used to:
A. Seal the pipe
B. Clean and soften the surface for solvent cement
C. Lubricate the fitting
D. Protect against corrosion
Primer ensures the solvent cement properly fuses the pipe and
fitting.
3. The term "backflow" refers to:
A. Water leaking from a pipe
B. Water flowing in the opposite direction, potentially
contaminating potable water
C. Water pressure fluctuations
D. Air entering the water system
Backflow can introduce contaminants into a drinking water
system, so prevention devices are critical.
4. Which of the following is a common backflow prevention
device?
, A. Ball valve
B. Check valve
C. Double check valve assembly (DCVA)
D. Gate valve
DCVAs prevent water from flowing back into the potable water
system under normal conditions.
5. The minimum size of a water service line for a single-family
dwelling is usually:
A. 15 mm
B. 20 mm
C. 25 mm
D. 40 mm
This ensures adequate flow and pressure for typical residential
fixtures.
6. What is the purpose of a pressure-reducing valve (PRV)?
A. Increase pressure
B. Reduce excessive incoming water pressure to safe levels
C. Control water temperature
D. Prevent backflow
High pressure can damage plumbing; PRVs protect pipes and
fixtures.
7. What is the standard pipe material for underground drainage in
Alberta?
A. Copper
B. Galvanized steel
C. PVC
D. PEX
PVC is durable, corrosion-resistant, and easy to install for
underground drainage.
8. When installing a water heater, the expansion tank is
, required to:
A. Heat water faster
B. Absorb excess pressure caused by thermal expansion
C. Filter impurities
D. Reduce noise
Thermal expansion in closed systems increases pressure; the
expansion tank prevents damage.
9. Which of the following is NOT allowed in a potable water
system?
A. Copper pipe
B. PEX tubing
C. Lead pipe
D. CPVC
Lead is banned in potable water systems due to its toxicity.
10. A P-trap must have a minimum water seal depth of:
A. 1/2 inch
B. 1 inch
C. 2 inches
D. 3 inches
A 2-inch water seal is sufficient to prevent sewer gases while
allowing smooth drainage.
11. In plumbing, what is a “cleanout”?
A. A type of vent
B. An access point for clearing blockages in a drain line
C. A pressure relief device
D. A type of faucet
Cleanouts provide convenient access to drain lines for
maintenance and unclogging.
12. Which method is recommended to test a new plumbing
installation for leaks?
