ALBERTA PLUMBER
APPRENTICESHIP
CERTIFICATION EXAM (THIRD
PERIOD) PRACTICE EXAM
COMPLETE (100 QUESTIONS
AND ANSWERS 2026 - 2027)
1. The primary purpose of a drainage, waste, and vent (DWV) system
is to:
A. Safely remove wastewater and protect trap seals through proper
venting
B. Supply potable water to fixtures
C. Deliver natural gas to appliances
D. Increase water pressure
Correct Answer: A
Rationale: A DWV system removes wastewater while maintaining
atmospheric pressure in the piping to protect trap seals and prevent
sewer gas from entering occupied spaces.
2. The minimum slope for a horizontal drainage pipe is intended to:
,A. Maintain proper flow velocity without allowing solids to settle
B. Increase water pressure
C. Reduce pipe diameter
D. Improve water temperature
Correct Answer: A
Rationale: Proper slope provides self-scouring flow while avoiding
excessive velocity that could leave solids behind.
3. A plumbing trap primarily prevents:
A. Sewer gases from entering the building
B. Water hammer
C. Pipe freezing
D. Excessive water pressure
Correct Answer: A
Rationale: The water seal maintained in the trap blocks sewer gases
while allowing wastewater to flow.
4. The purpose of a vent pipe is to:
,A. Equalize air pressure within the drainage system and protect trap
seals
B. Drain wastewater
C. Supply potable water
D. Deliver combustion air only
Correct Answer: A
Rationale: Proper venting prevents siphonage and back pressure.
5. A cleanout is installed primarily to:
A. Provide access for cleaning and inspecting drainage piping
B. Increase drainage flow
C. Reduce pipe friction
D. Vent the system
Correct Answer: A
Rationale: Cleanouts allow maintenance personnel to remove
blockages efficiently.
6. Which fitting provides the smoothest change of direction in a
drainage system?
, A. Long-radius elbow
B. Tee fitting
C. Coupling
D. Cap
Correct Answer: A
Rationale: Long-radius fittings reduce turbulence and improve
drainage performance.
7. The purpose of a building sewer is to:
A. Carry wastewater from the building drain to the municipal sewer
or private disposal system
B. Deliver potable water
C. Supply natural gas
D. Return condensate
Correct Answer: A
Rationale: The building sewer connects the building drainage system
to the public or private sewer.
8. Which factor most directly affects drainage pipe sizing?
APPRENTICESHIP
CERTIFICATION EXAM (THIRD
PERIOD) PRACTICE EXAM
COMPLETE (100 QUESTIONS
AND ANSWERS 2026 - 2027)
1. The primary purpose of a drainage, waste, and vent (DWV) system
is to:
A. Safely remove wastewater and protect trap seals through proper
venting
B. Supply potable water to fixtures
C. Deliver natural gas to appliances
D. Increase water pressure
Correct Answer: A
Rationale: A DWV system removes wastewater while maintaining
atmospheric pressure in the piping to protect trap seals and prevent
sewer gas from entering occupied spaces.
2. The minimum slope for a horizontal drainage pipe is intended to:
,A. Maintain proper flow velocity without allowing solids to settle
B. Increase water pressure
C. Reduce pipe diameter
D. Improve water temperature
Correct Answer: A
Rationale: Proper slope provides self-scouring flow while avoiding
excessive velocity that could leave solids behind.
3. A plumbing trap primarily prevents:
A. Sewer gases from entering the building
B. Water hammer
C. Pipe freezing
D. Excessive water pressure
Correct Answer: A
Rationale: The water seal maintained in the trap blocks sewer gases
while allowing wastewater to flow.
4. The purpose of a vent pipe is to:
,A. Equalize air pressure within the drainage system and protect trap
seals
B. Drain wastewater
C. Supply potable water
D. Deliver combustion air only
Correct Answer: A
Rationale: Proper venting prevents siphonage and back pressure.
5. A cleanout is installed primarily to:
A. Provide access for cleaning and inspecting drainage piping
B. Increase drainage flow
C. Reduce pipe friction
D. Vent the system
Correct Answer: A
Rationale: Cleanouts allow maintenance personnel to remove
blockages efficiently.
6. Which fitting provides the smoothest change of direction in a
drainage system?
, A. Long-radius elbow
B. Tee fitting
C. Coupling
D. Cap
Correct Answer: A
Rationale: Long-radius fittings reduce turbulence and improve
drainage performance.
7. The purpose of a building sewer is to:
A. Carry wastewater from the building drain to the municipal sewer
or private disposal system
B. Deliver potable water
C. Supply natural gas
D. Return condensate
Correct Answer: A
Rationale: The building sewer connects the building drainage system
to the public or private sewer.
8. Which factor most directly affects drainage pipe sizing?
