Kansas Journeyman Plumber
Examination — Local Jurisdiction
Practice Exam 2026 | 100 Questions &
Answers with Detailed Rationales |
Complete Exam Prep & Study Guide
1. A horizontal drainage pipe is installed with a diameter of 3 inches. For a
typical building sanitary drainage installation under the IPC, what is the
minimum slope generally required when the pipe is 3 inches or smaller?
A. 1/16 inch per foot
B. 1/8 inch per foot
C. 1/4 inch per foot
D. 1/2 inch per foot
Answer: 1/4 inch per foot
,Rationale: For smaller horizontal drainage piping, the IPC generally requires a
steeper minimum slope to maintain adequate scouring velocity. A 3-inch or
smaller drainage pipe commonly requires 1/4 inch per foot.
2. A 4-inch horizontal building drain is being installed where site conditions
make the normal slope difficult to maintain. What is the typical minimum
slope permitted for a 4-inch or larger drainage pipe?
A. 1/16 inch per foot
B. 1/8 inch per foot
C. 1/4 inch per foot
D. 1/2 inch per foot
Answer: 1/8 inch per foot
Rationale: Larger drainage piping can generally use a flatter minimum slope
because its greater diameter provides adequate hydraulic capacity and flow
characteristics.
3. A plumbing system has a cleanout installed at the base of a vertical
drainage stack. What is the principal purpose of this cleanout?
A. To increase ventilation
B. To provide access for cleaning the drainage system
C. To prevent backflow
D. To reduce water pressure
Answer: To provide access for cleaning the drainage system
Rationale: Cleanouts provide access to drainage piping for removing
obstructions and maintaining the system.
4. Which fitting is generally prohibited from being used as a drainage
connection when it would create an unfavorable flow pattern?
A. Wye
B. Sanitary tee in its permitted orientation
,C. Combination wye and one-eighth bend
D. Standard vent tee used improperly for horizontal drainage
Answer: Standard vent tee used improperly for horizontal drainage
Rationale: Drainage fittings must direct flow smoothly. Fittings intended for
venting or other purposes cannot simply be substituted where they would
disrupt drainage flow.
5. A water closet is located on a horizontal branch drain. Which fitting
provides the most appropriate directional transition from the closet
connection into the horizontal drainage system?
A. Sanitary tee laid on its back
B. Wye or approved combination fitting
C. Straight coupling
D. Vent tee
Answer: Wye or approved combination fitting
Rationale: Horizontal drainage connections should use fittings that promote
smooth directional flow and reduce the likelihood of turbulence and blockage.
6. What is the primary purpose of a plumbing trap?
A. Increase drainage velocity
B. Prevent sewer gases from entering the occupied space
C. Increase water pressure
D. Prevent hot water from entering a fixture
Answer: Prevent sewer gases from entering the occupied space
Rationale: The trap's water seal separates the drainage system from the
occupied building space and prevents the migration of sewer gases.
7. Two fixtures are proposed to discharge through a single trap. What is the
most important concern?
, A. The trap must be oversized
B. The arrangement must be specifically permitted by the applicable code
C. The fixtures must use different vent materials
D. The drain must be made of copper
Answer: The arrangement must be specifically permitted by the applicable code
Rationale: Each fixture generally requires an approved trap arrangement unless
the code specifically permits a shared or special trap configuration.
8. What condition can cause a trap seal to be lost because of pressure
changes in the drainage system?
A. Backpressure only
B. Siphonage
C. Thermal expansion
D. Water hammer
Answer: Siphonage
Rationale: Siphonage can occur when discharge from another fixture or stack
creates negative pressure that pulls water from the trap. Proper venting
protects trap seals.
9. What plumbing condition occurs when positive pressure in a drainage
system forces air or gases toward a fixture?
A. Back siphonage
B. Backpressure
C. Cavitation
D. Thermal expansion
Answer: Backpressure
Rationale: Backpressure occurs when positive pressure develops in the drainage
or vent system and can force air or gases toward fixture traps.
10.What is the primary function of a sanitary drainage vent system?
Examination — Local Jurisdiction
Practice Exam 2026 | 100 Questions &
Answers with Detailed Rationales |
Complete Exam Prep & Study Guide
1. A horizontal drainage pipe is installed with a diameter of 3 inches. For a
typical building sanitary drainage installation under the IPC, what is the
minimum slope generally required when the pipe is 3 inches or smaller?
A. 1/16 inch per foot
B. 1/8 inch per foot
C. 1/4 inch per foot
D. 1/2 inch per foot
Answer: 1/4 inch per foot
,Rationale: For smaller horizontal drainage piping, the IPC generally requires a
steeper minimum slope to maintain adequate scouring velocity. A 3-inch or
smaller drainage pipe commonly requires 1/4 inch per foot.
2. A 4-inch horizontal building drain is being installed where site conditions
make the normal slope difficult to maintain. What is the typical minimum
slope permitted for a 4-inch or larger drainage pipe?
A. 1/16 inch per foot
B. 1/8 inch per foot
C. 1/4 inch per foot
D. 1/2 inch per foot
Answer: 1/8 inch per foot
Rationale: Larger drainage piping can generally use a flatter minimum slope
because its greater diameter provides adequate hydraulic capacity and flow
characteristics.
3. A plumbing system has a cleanout installed at the base of a vertical
drainage stack. What is the principal purpose of this cleanout?
A. To increase ventilation
B. To provide access for cleaning the drainage system
C. To prevent backflow
D. To reduce water pressure
Answer: To provide access for cleaning the drainage system
Rationale: Cleanouts provide access to drainage piping for removing
obstructions and maintaining the system.
4. Which fitting is generally prohibited from being used as a drainage
connection when it would create an unfavorable flow pattern?
A. Wye
B. Sanitary tee in its permitted orientation
,C. Combination wye and one-eighth bend
D. Standard vent tee used improperly for horizontal drainage
Answer: Standard vent tee used improperly for horizontal drainage
Rationale: Drainage fittings must direct flow smoothly. Fittings intended for
venting or other purposes cannot simply be substituted where they would
disrupt drainage flow.
5. A water closet is located on a horizontal branch drain. Which fitting
provides the most appropriate directional transition from the closet
connection into the horizontal drainage system?
A. Sanitary tee laid on its back
B. Wye or approved combination fitting
C. Straight coupling
D. Vent tee
Answer: Wye or approved combination fitting
Rationale: Horizontal drainage connections should use fittings that promote
smooth directional flow and reduce the likelihood of turbulence and blockage.
6. What is the primary purpose of a plumbing trap?
A. Increase drainage velocity
B. Prevent sewer gases from entering the occupied space
C. Increase water pressure
D. Prevent hot water from entering a fixture
Answer: Prevent sewer gases from entering the occupied space
Rationale: The trap's water seal separates the drainage system from the
occupied building space and prevents the migration of sewer gases.
7. Two fixtures are proposed to discharge through a single trap. What is the
most important concern?
, A. The trap must be oversized
B. The arrangement must be specifically permitted by the applicable code
C. The fixtures must use different vent materials
D. The drain must be made of copper
Answer: The arrangement must be specifically permitted by the applicable code
Rationale: Each fixture generally requires an approved trap arrangement unless
the code specifically permits a shared or special trap configuration.
8. What condition can cause a trap seal to be lost because of pressure
changes in the drainage system?
A. Backpressure only
B. Siphonage
C. Thermal expansion
D. Water hammer
Answer: Siphonage
Rationale: Siphonage can occur when discharge from another fixture or stack
creates negative pressure that pulls water from the trap. Proper venting
protects trap seals.
9. What plumbing condition occurs when positive pressure in a drainage
system forces air or gases toward a fixture?
A. Back siphonage
B. Backpressure
C. Cavitation
D. Thermal expansion
Answer: Backpressure
Rationale: Backpressure occurs when positive pressure develops in the drainage
or vent system and can force air or gases toward fixture traps.
10.What is the primary function of a sanitary drainage vent system?
