MASSACHUSETTS PLUMBER JOURNEYMAN QUESTIONS
AND CORRECT ANSWERS (VERIFIED ANSWERS) Q&A
2026 |INSTANT DOWNLOAD PDF
1. What is the primary purpose of a plumbing vent system?
A. To increase water pressure
B. To allow gases to escape from the drainage system
C. To heat water in the pipes
D. To filter impurities from water
Rationale: Vent systems prevent the buildup of sewer gases
and maintain proper drainage flow.
Correct answer: B
2. What is the maximum distance a vent pipe can be from a
trap in a residential plumbing system?
A. 12 inches
B. 24 inches
C. 5 feet
D. 10 feet
Rationale: Plumbing codes specify maximum trap arm lengths
to ensure proper venting and prevent siphoning.
Correct answer: D
3. Which type of pipe is most commonly used for hot and
cold water distribution in residential buildings?
A. PVC
B. Copper
, C. Cast iron
D. Lead
Rationale: Copper is durable, heat-resistant, and code-
approved for potable water systems.
Correct answer: B
4. What is the correct way to join two copper pipes using a
sweat connection?
A. Apply solder to dry pipes without flux
B. Clean, apply flux, heat, and solder
C. Use PVC cement
D. Press-fit with no heat
Rationale: Proper cleaning, flux application, and soldering
ensure a leak-free copper connection.
Correct answer: B
5. What device is used to prevent backflow into a potable
water system?
A. Check valve
B. Pressure regulator
C. Gate valve
D. Air vent
Rationale: Check valves allow flow in one direction and prevent
contamination of drinking water.
Correct answer: A
6. What is the minimum slope required for a 2-inch
horizontal drain pipe?
, A. 1/4 inch per foot
B. 1/2 inch per foot
C. 1 inch per foot
D. 2 inches per foot
Rationale: Correct slope ensures proper drainage and prevents
clogs in residential plumbing.
Correct answer: A
7. Which tool is used to remove a clogged drain
mechanically?
A. Pipe wrench
B. Plunger
C. Auger (snake)
D. Adjustable wrench
Rationale: A plumbing auger can reach deep clogs beyond the
trap to clear blockages effectively.
Correct answer: C
8. What is the purpose of a pressure-reducing valve in a
water system?
A. Increase water flow
B. Reduce water temperature
C. Reduce excessive water pressure
D. Stop water flow completely
Rationale: PRVs protect pipes and fixtures from damage caused
by high water pressure.
Correct answer: C
, 9. What type of fitting is used to connect pipes at an angle
other than 90 degrees?
A. Coupling
B. Elbow
C. Tee
D. Reducer
Rationale: Elbows are angled fittings that change the direction
of the piping system.
Correct answer: B
10. Which material is commonly used for underground
drainage pipes?
A. Copper
B. PVC
C. PEX
D. Galvanized steel
Rationale: PVC is durable, corrosion-resistant, and suitable for
underground sewer and drain systems.
Correct answer: B
11. What is the purpose of a plumbing cleanout?
A. To add water to the system
B. To provide access for clearing blockages
C. To install a pressure gauge
D. To attach a hose
AND CORRECT ANSWERS (VERIFIED ANSWERS) Q&A
2026 |INSTANT DOWNLOAD PDF
1. What is the primary purpose of a plumbing vent system?
A. To increase water pressure
B. To allow gases to escape from the drainage system
C. To heat water in the pipes
D. To filter impurities from water
Rationale: Vent systems prevent the buildup of sewer gases
and maintain proper drainage flow.
Correct answer: B
2. What is the maximum distance a vent pipe can be from a
trap in a residential plumbing system?
A. 12 inches
B. 24 inches
C. 5 feet
D. 10 feet
Rationale: Plumbing codes specify maximum trap arm lengths
to ensure proper venting and prevent siphoning.
Correct answer: D
3. Which type of pipe is most commonly used for hot and
cold water distribution in residential buildings?
A. PVC
B. Copper
, C. Cast iron
D. Lead
Rationale: Copper is durable, heat-resistant, and code-
approved for potable water systems.
Correct answer: B
4. What is the correct way to join two copper pipes using a
sweat connection?
A. Apply solder to dry pipes without flux
B. Clean, apply flux, heat, and solder
C. Use PVC cement
D. Press-fit with no heat
Rationale: Proper cleaning, flux application, and soldering
ensure a leak-free copper connection.
Correct answer: B
5. What device is used to prevent backflow into a potable
water system?
A. Check valve
B. Pressure regulator
C. Gate valve
D. Air vent
Rationale: Check valves allow flow in one direction and prevent
contamination of drinking water.
Correct answer: A
6. What is the minimum slope required for a 2-inch
horizontal drain pipe?
, A. 1/4 inch per foot
B. 1/2 inch per foot
C. 1 inch per foot
D. 2 inches per foot
Rationale: Correct slope ensures proper drainage and prevents
clogs in residential plumbing.
Correct answer: A
7. Which tool is used to remove a clogged drain
mechanically?
A. Pipe wrench
B. Plunger
C. Auger (snake)
D. Adjustable wrench
Rationale: A plumbing auger can reach deep clogs beyond the
trap to clear blockages effectively.
Correct answer: C
8. What is the purpose of a pressure-reducing valve in a
water system?
A. Increase water flow
B. Reduce water temperature
C. Reduce excessive water pressure
D. Stop water flow completely
Rationale: PRVs protect pipes and fixtures from damage caused
by high water pressure.
Correct answer: C
, 9. What type of fitting is used to connect pipes at an angle
other than 90 degrees?
A. Coupling
B. Elbow
C. Tee
D. Reducer
Rationale: Elbows are angled fittings that change the direction
of the piping system.
Correct answer: B
10. Which material is commonly used for underground
drainage pipes?
A. Copper
B. PVC
C. PEX
D. Galvanized steel
Rationale: PVC is durable, corrosion-resistant, and suitable for
underground sewer and drain systems.
Correct answer: B
11. What is the purpose of a plumbing cleanout?
A. To add water to the system
B. To provide access for clearing blockages
C. To install a pressure gauge
D. To attach a hose
