Missouri Plumbing Inspector Level II
Exam Practice Questions And Correct
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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 install plumbing fixtures
C. To verify compliance with plumbing codes
D. To approve contractor payment
C. To verify compliance with plumbing codes
The primary purpose of a plumbing inspection is to ensure that all
installations comply with applicable plumbing codes and standards
for safety and functionality.
2. Which code is most commonly adopted for plumbing inspections in
Missouri?
A. National Fire Code
, B. International Plumbing Code (IPC)
C. OSHA Construction Code
D. National Electrical Code
B. International Plumbing Code (IPC)
Missouri jurisdictions commonly adopt the International Plumbing
Code, which governs plumbing system design, installation, and
inspection requirements.
3. What is the minimum slope for a 3-inch horizontal drain pipe under
IPC?
A. 1/8 inch per foot
B. 1/4 inch per foot
C. 1/2 inch per foot
D. 1 inch per foot
A. 1/8 inch per foot
The IPC allows a minimum slope of 1/8 inch per foot for 3-inch and
larger horizontal drainage piping under certain conditions to ensure
proper flow.
4. A plumbing inspector’s authority primarily includes:
A. Hiring plumbing contractors
B. Approving system design changes in the field
C. Enforcing code compliance
D. Performing plumbing installations
C. Enforcing code compliance
, Plumbing inspectors are responsible for enforcing code requirements
and ensuring installations meet approved standards.
5. Which test is commonly used to check drain, waste, and vent (DWV)
systems?
A. Hydrostatic test
B. Vacuum test
C. Gas pressure test
D. Electrical continuity test
A. Hydrostatic test
DWV systems are typically tested using water under hydrostatic
pressure to verify leak-free performance.
6. What is required before covering underground plumbing piping?
A. Final inspection approval
B. Pressure test approval
C. Permit expiration
D. Contractor certification
B. Pressure test approval
Underground piping must pass required pressure or water tests
before being covered to ensure integrity and compliance.
7. Which material is NOT approved for DWV systems under IPC?
A. PVC
B. Cast iron
C. Galvanized steel
, D. Polyethylene foam
D. Polyethylene foam
Polyethylene foam is not a recognized piping material for DWV
systems in plumbing codes.
8. The purpose of a vent system is to:
A. Increase water pressure
B. Prevent sewer gases from entering buildings
C. Drain wastewater faster
D. Heat water lines
B. Prevent sewer gases from entering buildings
Vent systems allow sewer gases to escape and maintain trap seals,
preventing harmful gases from entering occupied spaces.
9. What is the minimum water supply pressure generally required for
fixtures?
A. 10 psi
B. 20 psi
C. 25 psi
D. 35 psi
B. 20 psi
A minimum of 20 psi is generally required to ensure proper fixture
operation and consistent water delivery.
10. Which fitting is used to change direction in a drainage system?
A. Coupling
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 install plumbing fixtures
C. To verify compliance with plumbing codes
D. To approve contractor payment
C. To verify compliance with plumbing codes
The primary purpose of a plumbing inspection is to ensure that all
installations comply with applicable plumbing codes and standards
for safety and functionality.
2. Which code is most commonly adopted for plumbing inspections in
Missouri?
A. National Fire Code
, B. International Plumbing Code (IPC)
C. OSHA Construction Code
D. National Electrical Code
B. International Plumbing Code (IPC)
Missouri jurisdictions commonly adopt the International Plumbing
Code, which governs plumbing system design, installation, and
inspection requirements.
3. What is the minimum slope for a 3-inch horizontal drain pipe under
IPC?
A. 1/8 inch per foot
B. 1/4 inch per foot
C. 1/2 inch per foot
D. 1 inch per foot
A. 1/8 inch per foot
The IPC allows a minimum slope of 1/8 inch per foot for 3-inch and
larger horizontal drainage piping under certain conditions to ensure
proper flow.
4. A plumbing inspector’s authority primarily includes:
A. Hiring plumbing contractors
B. Approving system design changes in the field
C. Enforcing code compliance
D. Performing plumbing installations
C. Enforcing code compliance
, Plumbing inspectors are responsible for enforcing code requirements
and ensuring installations meet approved standards.
5. Which test is commonly used to check drain, waste, and vent (DWV)
systems?
A. Hydrostatic test
B. Vacuum test
C. Gas pressure test
D. Electrical continuity test
A. Hydrostatic test
DWV systems are typically tested using water under hydrostatic
pressure to verify leak-free performance.
6. What is required before covering underground plumbing piping?
A. Final inspection approval
B. Pressure test approval
C. Permit expiration
D. Contractor certification
B. Pressure test approval
Underground piping must pass required pressure or water tests
before being covered to ensure integrity and compliance.
7. Which material is NOT approved for DWV systems under IPC?
A. PVC
B. Cast iron
C. Galvanized steel
, D. Polyethylene foam
D. Polyethylene foam
Polyethylene foam is not a recognized piping material for DWV
systems in plumbing codes.
8. The purpose of a vent system is to:
A. Increase water pressure
B. Prevent sewer gases from entering buildings
C. Drain wastewater faster
D. Heat water lines
B. Prevent sewer gases from entering buildings
Vent systems allow sewer gases to escape and maintain trap seals,
preventing harmful gases from entering occupied spaces.
9. What is the minimum water supply pressure generally required for
fixtures?
A. 10 psi
B. 20 psi
C. 25 psi
D. 35 psi
B. 20 psi
A minimum of 20 psi is generally required to ensure proper fixture
operation and consistent water delivery.
10. Which fitting is used to change direction in a drainage system?
A. Coupling
