INSTALLER EXAM - 350 PRACTICE
QUESTIONS
Section 1: Plumbing Fundamentals & Terminology (Questions 1-40)
Question 1
What is the primary purpose of a plumbing system?
A) Electrical distribution
B) Transport water and waste safely
C) Heating air
D) Structural support
Answer: B
Rationale: Plumbing systems deliver clean water and remove wastewater
safely.
Question 2
What does DWV stand for in plumbing terminology?
A) Drain, Water, Valve
B) Drain, Waste, Vent
C) Domestic Water Volume
D) Direct Waste Valve
Answer: B
Rationale: DWV systems remove wastewater and gases from buildings.
,Question 3
What is the function of a vent pipe in a plumbing system?
A) Increase water pressure
B) Allow sewer gases to escape and equalize pressure
C) Carry clean water
D) Store water
Answer: B
Rationale: Vents prevent trap siphoning and allow proper drainage.
Question 4
What is a trap in plumbing?
A) Water storage tank
B) U-shaped pipe preventing sewer gas entry
C) Pressure valve
D) Pump system
Answer: B
Rationale: Traps hold water to block sewer gases from entering buildings.
Question 5
What is the purpose of a P-trap?
A) Increase flow
B) Prevent odors from entering building
C) Reduce water pressure
D) Filter debris
,Answer: B
Rationale: P-traps create a water seal that prevents sewer gases from entering
the building.
Question 6
Which material is commonly used for potable water supply piping?
A) Cast iron
B) Copper
C) PVC for hot water
D) Lead
Answer: B
Rationale: Copper is commonly used for potable water supply piping due to its
durability and corrosion resistance.
Question 7
What is the minimum required size for a building sewer?
A) 1.5 inches
B) 2 inches
C) 3 inches
D) 4 inches
Answer: C
Rationale: The minimum size for a building sewer is 3 inches to ensure
adequate flow and prevent blockages.
Question 8
, What is the DFU (Drainage Fixture Unit) value for a bathtub without a
shower?
A) 1 DFU
B) 2 DFU
C) 3 DFU
D) 4 DFU
Answer: B
Rationale: Per the IPC, a bathtub without a shower has a DFU value of 2. A
bathtub with a shower attachment has the same DFU value.
Question 9
Which Virginia agency administers the journeyman plumber license?
A) Virginia Department of Labor and Industry
B) Virginia Department of Professional and Occupational Regulation (DPOR)
C) Virginia Board of Health
D) Virginia Department of Housing and Community Development
Answer: B
Rationale: DPOR administers the journeyman plumber license through its
Board for Contractors and oversees all trade licensing in Virginia.
Question 10
What plumbing code does Virginia use as the basis for its plumbing
regulations?
A) Uniform Plumbing Code (UPC)
B) National Standard Plumbing Code (NSPC)
C) International Plumbing Code (IPC) as part of the Virginia Uniform
Statewide Building Code (USBC)