[TEXAS JOURNEYMAN PLUMBER LICENSE EXAM] – QUESTIONS AND ANSWERS | VERIFIED
AND WELL DETAILED ANSWERS | PLUS RATIONALES | GUARANTEED PASS | LATEST EXAM
UPDATE | EXAM PREP | STUDY GUIDE | PRACTICE TEST
1. A plumber is installing a new water service line to a commercial building. What is the
primary purpose of a backflow prevention assembly?
A. Increase water pressure
B. Reduce pipe corrosion
C. Prevent contamination of the potable water supply
D. Improve drainage flow
════════════════════
Correct Answer: C. Prevent contamination of the potable water supply
Rationale:
Backflow prevention devices protect drinking water systems by preventing contaminated
water from flowing backward into the public water supply. The other options are unrelated to
the primary function of backflow protection.
════════════════════
2. Which fitting is commonly used to connect two pipes of different diameters in a drainage
system?
A. Coupling
B. Reducer
C. Tee
D. Union
════════════════════
Correct Answer: B. Reducer
Rationale:
A reducer is specifically designed to join pipes of different sizes. Couplings join similar-sized
pipes, tees create branches, and unions allow disconnection.
════════════════════
3. A trap seal primarily helps prevent what condition?
A. Pipe freezing
B. Water hammer
,C. Excessive pressure
D. Sewer gases entering occupied spaces
════════════════════
Correct Answer: D. Sewer gases entering occupied spaces
Rationale:
The water held in a trap forms a seal that blocks sewer gases from entering buildings. It is not
intended to control pressure, freezing, or water hammer.
════════════════════
4. What is the most appropriate first step when responding to a reported gas leak inside a
building?
A. Ignite appliances to test the gas supply
B. Increase water pressure
C. Shut off the gas source if safe to do so
D. Flush nearby fixtures
════════════════════
Correct Answer: C. Shut off the gas source if safe to do so
Rationale:
Protecting life and property is the priority. Safely stopping the gas flow helps reduce risk while
emergency procedures are initiated.
════════════════════
5. Which type of pipe is widely used for residential water distribution systems due to
flexibility and corrosion resistance?
A. Cast iron
B. PEX
C. Clay
D. Concrete
════════════════════
Correct Answer: B. PEX
Rationale:
,PEX is commonly used because it is flexible, durable, and resistant to corrosion. The other
materials are generally not used for interior potable water distribution.
════════════════════
6. What plumbing component is designed to absorb pressure surges caused by quick-closing
valves?
A. Expansion tank
B. Cleanout
C. Air admittance valve
D. Water hammer arrestor
════════════════════
Correct Answer: D. Water hammer arrestor
Rationale:
A water hammer arrestor reduces shock waves created by sudden valve closure. This helps
protect piping and fixtures from damage.
════════════════════
7. During a rough-in inspection, what is the inspector primarily verifying?
A. Fixture color selection
B. Structural engineering calculations
C. Proper installation before concealment
D. Utility billing records
════════════════════
Correct Answer: C. Proper installation before concealment
Rationale:
Rough-in inspections ensure plumbing work complies with code before walls, floors, or
ceilings are closed.
════════════════════
8. What is the purpose of a cleanout in a drainage system?
A. Increase water pressure
B. Provide access for maintenance and blockage removal
, C. Reduce water temperature
D. Prevent pipe expansion
════════════════════
Correct Answer: B. Provide access for maintenance and blockage removal
Rationale:
Cleanouts allow plumbers to inspect and clear obstructions within drainage systems
efficiently.
════════════════════
9. Which drain piping material is known for excellent sound-deadening characteristics in
commercial buildings?
A. PVC
B. CPVC
C. Cast iron
D. PEX
════════════════════
Correct Answer: C. Cast iron
Rationale:
Cast iron is valued for reducing drainage noise and providing durability in commercial
applications.
════════════════════
10. A plumber notices evidence of cross-connection between potable and non-potable
systems. What should be done?
A. Ignore it if no complaints exist
B. Increase pressure in both systems
C. Document it only
D. Eliminate the cross-connection and provide proper protection
════════════════════
Correct Answer: D. Eliminate the cross-connection and provide proper protection
Rationale:
AND WELL DETAILED ANSWERS | PLUS RATIONALES | GUARANTEED PASS | LATEST EXAM
UPDATE | EXAM PREP | STUDY GUIDE | PRACTICE TEST
1. A plumber is installing a new water service line to a commercial building. What is the
primary purpose of a backflow prevention assembly?
A. Increase water pressure
B. Reduce pipe corrosion
C. Prevent contamination of the potable water supply
D. Improve drainage flow
════════════════════
Correct Answer: C. Prevent contamination of the potable water supply
Rationale:
Backflow prevention devices protect drinking water systems by preventing contaminated
water from flowing backward into the public water supply. The other options are unrelated to
the primary function of backflow protection.
════════════════════
2. Which fitting is commonly used to connect two pipes of different diameters in a drainage
system?
A. Coupling
B. Reducer
C. Tee
D. Union
════════════════════
Correct Answer: B. Reducer
Rationale:
A reducer is specifically designed to join pipes of different sizes. Couplings join similar-sized
pipes, tees create branches, and unions allow disconnection.
════════════════════
3. A trap seal primarily helps prevent what condition?
A. Pipe freezing
B. Water hammer
,C. Excessive pressure
D. Sewer gases entering occupied spaces
════════════════════
Correct Answer: D. Sewer gases entering occupied spaces
Rationale:
The water held in a trap forms a seal that blocks sewer gases from entering buildings. It is not
intended to control pressure, freezing, or water hammer.
════════════════════
4. What is the most appropriate first step when responding to a reported gas leak inside a
building?
A. Ignite appliances to test the gas supply
B. Increase water pressure
C. Shut off the gas source if safe to do so
D. Flush nearby fixtures
════════════════════
Correct Answer: C. Shut off the gas source if safe to do so
Rationale:
Protecting life and property is the priority. Safely stopping the gas flow helps reduce risk while
emergency procedures are initiated.
════════════════════
5. Which type of pipe is widely used for residential water distribution systems due to
flexibility and corrosion resistance?
A. Cast iron
B. PEX
C. Clay
D. Concrete
════════════════════
Correct Answer: B. PEX
Rationale:
,PEX is commonly used because it is flexible, durable, and resistant to corrosion. The other
materials are generally not used for interior potable water distribution.
════════════════════
6. What plumbing component is designed to absorb pressure surges caused by quick-closing
valves?
A. Expansion tank
B. Cleanout
C. Air admittance valve
D. Water hammer arrestor
════════════════════
Correct Answer: D. Water hammer arrestor
Rationale:
A water hammer arrestor reduces shock waves created by sudden valve closure. This helps
protect piping and fixtures from damage.
════════════════════
7. During a rough-in inspection, what is the inspector primarily verifying?
A. Fixture color selection
B. Structural engineering calculations
C. Proper installation before concealment
D. Utility billing records
════════════════════
Correct Answer: C. Proper installation before concealment
Rationale:
Rough-in inspections ensure plumbing work complies with code before walls, floors, or
ceilings are closed.
════════════════════
8. What is the purpose of a cleanout in a drainage system?
A. Increase water pressure
B. Provide access for maintenance and blockage removal
, C. Reduce water temperature
D. Prevent pipe expansion
════════════════════
Correct Answer: B. Provide access for maintenance and blockage removal
Rationale:
Cleanouts allow plumbers to inspect and clear obstructions within drainage systems
efficiently.
════════════════════
9. Which drain piping material is known for excellent sound-deadening characteristics in
commercial buildings?
A. PVC
B. CPVC
C. Cast iron
D. PEX
════════════════════
Correct Answer: C. Cast iron
Rationale:
Cast iron is valued for reducing drainage noise and providing durability in commercial
applications.
════════════════════
10. A plumber notices evidence of cross-connection between potable and non-potable
systems. What should be done?
A. Ignore it if no complaints exist
B. Increase pressure in both systems
C. Document it only
D. Eliminate the cross-connection and provide proper protection
════════════════════
Correct Answer: D. Eliminate the cross-connection and provide proper protection
Rationale:
