Missouri Plumbing Inspector Level II —
Lee’s Summit Exam Practice Questions
And Correct Answers (Verified Answers)
Plus Rationales 2026 Q&A | Instant
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1. What is the primary purpose of a plumbing inspection?
A. To design plumbing systems
B. To ensure compliance with codes and safety standards
C. To install plumbing systems
D. To estimate project costs
Answer: B
Rationale: The main role of inspection is to verify code compliance
and ensure public health and safety.
2. Which code is most commonly used for plumbing inspections in
Missouri jurisdictions?
A. NEC
B. IMC
, C. IPC
D. NFPA 70
Answer: C
Rationale: The International Plumbing Code (IPC) is widely adopted
for plumbing regulation.
3. What is the minimum slope for a 3-inch horizontal drain line?
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: B
Rationale: 3-inch drains typically require 1/8 inch per foot slope for
proper flow.
4. What is the purpose of a trap in a plumbing system?
A. Increase water pressure
B. Prevent sewer gases from entering buildings
C. Improve drainage speed
D. Filter solids
Answer: B
Rationale: Traps maintain a water seal that blocks sewer gases.
5. What is the minimum trap seal depth?
A. 1 inch
, B. 2 inches
C. 4 inches
D. 6 inches
Answer: B
Rationale: Standard trap seals are typically 2 inches deep minimum.
6. Which pipe material is commonly prohibited for potable water in
modern codes?
A. Copper
B. PEX
C. Galvanized steel
D. CPVC
Answer: C
Rationale: Galvanized steel corrodes internally and is often restricted
for potable use.
7. What is required after a rough-in inspection?
A. Final grading
B. Wall insulation
C. Pressure test approval before concealment
D. Painting approval
Answer: C
Rationale: Systems must pass pressure tests before being concealed.
, 8. What is the minimum air gap required for indirect waste?
A. 1 inch
B. Twice the pipe diameter
C. Equal to pipe diameter
D. 6 inches
Answer: B
Rationale: Air gap must be at least twice the diameter of the outlet
for backflow prevention.
9. What device prevents backflow into potable water systems?
A. Trap
B. Cleanout
C. Backflow preventer
D. Vent stack
Answer: C
Rationale: Backflow preventers stop reverse flow contamination.
10. What is the function of a vent system?
A. Increase water pressure
B. Remove wastewater solids
C. Allow air circulation to maintain trap seals
D. Heat water
Answer: C
Lee’s Summit Exam Practice Questions
And Correct Answers (Verified Answers)
Plus Rationales 2026 Q&A | Instant
Download Pdf
1. What is the primary purpose of a plumbing inspection?
A. To design plumbing systems
B. To ensure compliance with codes and safety standards
C. To install plumbing systems
D. To estimate project costs
Answer: B
Rationale: The main role of inspection is to verify code compliance
and ensure public health and safety.
2. Which code is most commonly used for plumbing inspections in
Missouri jurisdictions?
A. NEC
B. IMC
, C. IPC
D. NFPA 70
Answer: C
Rationale: The International Plumbing Code (IPC) is widely adopted
for plumbing regulation.
3. What is the minimum slope for a 3-inch horizontal drain line?
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: B
Rationale: 3-inch drains typically require 1/8 inch per foot slope for
proper flow.
4. What is the purpose of a trap in a plumbing system?
A. Increase water pressure
B. Prevent sewer gases from entering buildings
C. Improve drainage speed
D. Filter solids
Answer: B
Rationale: Traps maintain a water seal that blocks sewer gases.
5. What is the minimum trap seal depth?
A. 1 inch
, B. 2 inches
C. 4 inches
D. 6 inches
Answer: B
Rationale: Standard trap seals are typically 2 inches deep minimum.
6. Which pipe material is commonly prohibited for potable water in
modern codes?
A. Copper
B. PEX
C. Galvanized steel
D. CPVC
Answer: C
Rationale: Galvanized steel corrodes internally and is often restricted
for potable use.
7. What is required after a rough-in inspection?
A. Final grading
B. Wall insulation
C. Pressure test approval before concealment
D. Painting approval
Answer: C
Rationale: Systems must pass pressure tests before being concealed.
, 8. What is the minimum air gap required for indirect waste?
A. 1 inch
B. Twice the pipe diameter
C. Equal to pipe diameter
D. 6 inches
Answer: B
Rationale: Air gap must be at least twice the diameter of the outlet
for backflow prevention.
9. What device prevents backflow into potable water systems?
A. Trap
B. Cleanout
C. Backflow preventer
D. Vent stack
Answer: C
Rationale: Backflow preventers stop reverse flow contamination.
10. What is the function of a vent system?
A. Increase water pressure
B. Remove wastewater solids
C. Allow air circulation to maintain trap seals
D. Heat water
Answer: C
