(NEW UPDATED VERSION) LATEST ACTUAL EXAM QUESTIONS AND CORRECT ANSWERS
(VERIFIED QUESTIONS AND ANSWERS) | GUARANTEED PASS A+ [2026]
Texas Master Plumber Practice Exam
Texas Master Plumber Practice Exam – Questions 1–75
1–10: Plumbing Codes & Regulations
1. The maximum number of fixture units on a 2-inch horizontal drainage pipe is:
• A. 12
• B. 20
• C. 28
• D. 32
Answer: C — Per IPC Table 703.2, a 2-inch horizontal pipe can carry up to 28 fixture units.
2. In Texas, which code governs plumbing installations?
• A. UPC
• B. IPC
• C. TSBPE rules
• D. All of the above
Answer: D — Texas adopts TSBPE rules, referencing both UPC and IPC depending on
jurisdiction.
3. Minimum water supply pipe size for a single-family dwelling’s kitchen sink:
• A. ½ inch
• B. ¾ inch
• C. 1 inch
• D. 1¼ inch
Answer: A — Standard minimum is ½-inch pipe for kitchen sinks.
4. A relief valve is required on a water heater when:
• A. Pressure exceeds 150 psi
• B. Temperature exceeds 210°F
• C. Both A and B
2026 Graded A+ EXAM
, • D. Only when installed outdoors
Answer: C — Relief valves protect against excessive pressure or temperature.
5. Trap arm for a 1½-inch P-trap must have a maximum length of:
• A. 3 feet
• B. 4 feet
• C. 5 feet
• D. 6 feet
Answer: B — Per IPC, max trap arm length for 1½-inch trap is 4 feet.
6. Minimum slope for a 3-inch horizontal DWV pipe:
• A. 1/4 inch per foot
• B. 1/8 inch per foot
• C. 1/2 inch per foot
• D. 1 inch per foot
Answer: A — Standard minimum slope for proper drainage is 1/4 inch per foot.
7. Backflow prevention is required on:
• A. Boiler feed
• B. Irrigation systems
• C. Chemical solution lines
• D. All of the above
Answer: D — Any potential contamination source must have backflow prevention.
8. Approved materials for potable water distribution include:
• A. CPVC
• B. PEX
• C. Copper
• D. All of the above
Answer: D — All are approved under TSBPE rules.
9. Maximum water temperature allowed at plumbing fixtures:
• A. 120°F
• B. 140°F
• C. 160°F
• D. 180°F
2026 Graded A+ EXAM
,Answer: A — 120°F is standard for domestic hot water to prevent scalding.
10. In Texas, a master plumber license must be renewed every:
• A. 1 year
• B. 2 years
• C. 3 years
• D. 5 years
Answer: B — Master plumber licenses renew biennially.
11–20: Pipe Sizing & Fixture Units
11. Total fixture units for a bathroom with a lavatory (1), water closet (2), and shower (2) is:
• A. 4
• B. 5
• C. 6
• D. 7
Answer: D — Lavatory=1, Water Closet=3 (per IPC), Shower=2 → total = 6. Correction:
Actually Lavatory=1, Water Closet=3, Shower=2 → Total = 6.
12. Minimum vent pipe size for a 2-inch drain:
• A. 1 inch
• B. 1½ inch
• C. 2 inch
• D. 3 inch
Answer: B — Vent pipe must be at least 1½ inches for a 2-inch drain.
13. Maximum distance from trap to vent for a 1½-inch trap:
• A. 2 feet
• B. 3 feet
• C. 4 feet
• D. 5 feet
Answer: C — Per IPC, max trap arm distance is 4 feet.
14. A building with 4 bathrooms and a kitchen sink requires what minimum water service size:
• A. ¾ inch
2026 Graded A+ EXAM
, • B. 1 inch
• C. 1¼ inch
• D. 1½ inch
Answer: B — Multiple bathrooms require 1-inch minimum service.
15. Horizontal drainage piping should be supported:
• A. Every 4 feet
• B. Every 5 feet
• C. Every 6 feet
• D. Every 8 feet
Answer: A — Pipe supports for horizontal DWV per IPC: 4 ft max for 3-inch or smaller.
16. Trap depth for a 2-inch DWV line:
• A. 2 inches
• B. 3 inches
• C. 4 inches
• D. 5 inches
Answer: B — Minimum trap depth is 2–4 inches; commonly 3 inches.
17. Minimum water pressure required at fixture:
• A. 10 psi
• B. 20 psi
• C. 30 psi
• D. 40 psi
Answer: C — Standard minimum fixture pressure is 30 psi.
18. Branch interval sizing is calculated using:
• A. Total fixture units on branch
• B. Length of pipe
• C. Both A and B
• D. Only number of floors
Answer: C — Branch sizing depends on total fixture units and distance.
19. Maximum number of fixture units on a 4-inch horizontal pipe:
• A. 50
• B. 64
2026 Graded A+ EXAM