Sanitary Drainage Practice Questions
Slope, drainage fixture units, change-of-direction fittings, cleanouts, sizing, sumps and ejectors, backwater valves, indirect waste and building sewers.
100 questions in 2 hours, scored against the 70% pass mark, with a score for sanitary drainage so you know where you stand.
Free sanitary drainage drillA sump that receives sewage must have:
Sanitary Drainage on the journeyman plumber exam
TSBPE’s sanitary drainage chapter covers approved materials, installation, cleanouts, testing and the separation of the building drain from the water service. ICC’s Sanitary Drainage area is 13% of G25 and includes sumps, ejectors, and indirect and special wastes.
- On our mocks
- Texas: 12 of 100 on our Texas mock · ICC G25: 9 of 70 on our ICC G25 mock
- Our drill
- 10 questions from 40 sanitary drainage questions, untimed, an explanation and code reference after every answer; one free attempt, unlimited with a pass
What sanitary drainage questions test
- Slope: 1/4 inch per foot for drains 2-1/2 inches and smaller, and the IPC’s 1/8 inch per foot for 3 to 6 inches
- Drainage fixture units for common fixtures and how drains are sized from them
- Fittings: sanitary tees horizontal-to-vertical only, long sweeps or wye and 1/8 bend vertical-to-horizontal
- Cleanouts: 100-foot spacing, size up to 4 inches, 18 inches of clearance, and the building drain-sewer junction
- Sumps and ejectors, backwater valves, indirect waste and receptors, chemical waste and the building sewer
Sit the full exam under the real clock
100 questions in 2 hours, scored against the 70% pass mark, with a score for sanitary drainage so you know where you stand.
Free sanitary drainage drillHow to study it
- Learn the dfu values for a lavatory (1), tub, shower and kitchen sink (2) and water closet (3 or more).
- Sketch each change of direction and name the fitting it needs.
- Remember what never goes in a sanitary drain: storm water.
Common questions
What slope does a 2-inch drain need?
At least 1/4 inch per foot in both codes. Larger drains may use less: the IPC allows 1/8 inch per foot for 3- to 6-inch drains.
How far apart must cleanouts be?
Not more than 100 feet apart in horizontal drainage lines, in both codes.
100 questions in 2 hours, scored against the 70% pass mark, with a score for sanitary drainage so you know where you stand.
Free sanitary drainage drillThe other sections
- Code Definitions and Plan Reading
- General Regulations, Testing and Plumbing Math
- Pipe Materials and Joints
- Plumbing Fixtures
- Water Heaters
- Water Supply and Distribution
- Vents
- Traps, Interceptors and Separators
- Storm Drainage
- Fuel Gas Piping
- Texas Plumbing License Law and Board Rules
- Texas practice exam (100 questions, 2 hours)
- ICC G25 practice exam (70 questions, 4 hours)
- Free Texas mixed drill
Sources
- Pearson VUE: Texas State Board of Plumbing Examiners (retake waits, practical, five attempts)
- TSBPE Candidate Handbook, August 2025 (exam table, fees, 70% passing score, test-center rules)
- TSBPE Journeyman Plumber Examination Review Course, rev 09/2025 (format, codes, chapters, sample questions)
- TSBPE Administrative Rules, March 2026 (22 TAC §§363.5, 363.22, 365.1, 367.2)
- TSBPE proposed amendment to §367.2 (2021 IPC and UPC), Texas Register, August 14, 2026
- TSBPE Strategic Plan 2025-2029 (examination statistics, p. 14)
- ICC National Contractor/Trades Examination Information Bulletin, published June 30, 2026 (G25 Journeyman Plumber)
- ICC Support: What is a passing score?
Original practice questions written to the TSBPE Journeyman Plumber Examination Review Course, ICC’s G25 content outline and the 2018 International Plumbing Code and Uniform Plumbing Code; they are not exam questions and quote no code text. Independent practice, not affiliated with or endorsed by the Texas State Board of Plumbing Examiners, the International Code Council, IAPMO or Pearson VUE.