Checked 27 October 2026. The worked examples are written on the International Plumbing Code, 2024 edition. Section numbers move between editions, and some jurisdictions use the Uniform Plumbing Code, so check which code your exam tests. Format facts from the Oklahoma PSI bulletin effective 11 September 2026 and the CIB notice of 31 August 2026, read 27 October 2026.
People look for journeyman plumber practice test questions to find out what the exam asks and how fast they can answer. The official sources read for this guide contain no actual exam questions, so the useful practice is questions written from the same code book, worked by finding and applying the relevant rule or table. This page works through two of ours on the 2024 IPC, one vent sizing problem and one code lookup, then sets out the sizing methods and tables the calculation questions lean on, and what each area of a published outline asks.
ProSyllabus is an independent study site. It is not PSI, a state licensing board or the International Code Council, and nothing here is an exam paper. Exam facts on this page come from the official bulletin and board pages listed at the foot of the page.
Exam facts: Oklahoma Construction Industries Board, PSI Candidate Information Bulletin, effective 11 Sep 2026 (read 27 Oct 2026).
How to use the worked examples
Have the 2024 IPC open for these examples, and check your own exam’s code and book rules. Pick an answer before you open "Show the answer", and time yourself: 180 minutes for 85 questions on Oklahoma’s Plumbing Journeyman and Natural Gas exam averages about 2.1 minutes a question (our arithmetic). Then read the reason and the section it rests on, and find that section in your own book. Knowing where a rule sits is what lets you answer a differently worded question on it.
FreeTests: Area 4: Water supply · Area 5: Drains and sewers · Area 6: Vents
Journeyman Plumber Practice Test: free sample
Answer 3 questions against the clock, like the real exam. You then see the right answer, the reason and your time on each. About 8 minutes · free · no sign-in.
3 questions to answer▶ Start nowThis one is free · no sign-in neededYour result shows how long each question took you.Worked example 1: sizing a branch vent
Worked example 1 · Area 6: Vents
A branch vent serves a drain that Table 710.1(2) requires to be 3 in, and has a developed length of 55 ft. What is the minimum vent size?
- (A) 1-1/2 in
- (B) 3 in
- (C) 1-1/4 in
- (D) 2 in
Show the answer
Answer: (D) 2 in. 1) IPC 2024 Section 906.2: half the required 3 in drain is 1-1/2 in. 2) Vents longer than 40 ft in developed length must be increased one nominal pipe size for their entire length. 3) 55 ft > 40 ft, so 1-1/2 in goes up one size to 2 in.
Section to reread: IPC 2024 Section 906.2
An original ProSyllabus question written from the 2024 International Plumbing Code. Not a question from any exam.
Why it matters: vents are the largest single area of the published outline, 13 of its 85 questions. The method for individual, branch and circuit vents (Section 906.2): find the size the drain served is required to be, take half of it (never less than 1-1/4 in), then add one pipe size for the whole vent if its developed length is over 40 ft. Stack vents and vent stacks are sized from Table 906.1, and relief vents for stacks of more than ten branch intervals follow Section 908.
Worked example 2: a code lookup
Worked example 2 · Area 4: Water supply
The static water pressure in a building is 95 psi. What does the IPC require?
- (A) A thermal expansion tank on the water service only
- (B) Nothing, because the limit is 125 psi
- (C) A pressure-reducing valve that keeps static pressure at 80 psi or less
- (D) A booster pump, because pressure that high starves the upper floors of water
Show the answer
Answer: (C) A pressure-reducing valve that keeps static pressure at 80 psi or less. IPC 2024 Section 604.8 requires an approved water-pressure reducing valve, conforming to ASSE 1003 or CSA B356 and with a strainer, where the static pressure within a building exceeds 80 psi, to reduce the pressure in the distribution piping to 80 psi static or less.
Section to reread: IPC 2024 Section 604.8
An original ProSyllabus question written from the 2024 International Plumbing Code. Not a question from any exam.
Why it matters: many water supply questions are a single lookup once you know which section governs. The trap is mixing up limits that sound alike: the static pressure that calls for a pressure-reducing valve, the flow pressure a fixture needs (Table 604.3) and the maximum flow rate of a fitting (Table 604.4). Read which one the question asks about before you open the book.
- Full mock: 85 questions, 180-minute clock, split by the published outline
- A sizing and calculations set, every problem worked line by line
- A set for each of the 10 outline areas
- Every answer names its IPC or IFGC 2024 section, or its OSHA 1926 section for safety
- Code sections to reread for each question you miss
- 3 questions free
Sizing methods the calculation questions use
| Calculation | Method |
|---|---|
| Drainage fixture units | Add the dfu of each fixture from Table 709.1 (Table 709.2 for fixtures not listed; 2 dfu per gpm of continuous flow, Section 709.3) |
| Building drain or sewer | Read Table 710.1(1) at the drain’s slope; take the first size whose dfu limit covers the load |
| Horizontal fixture branches and stacks | Table 710.1(2): the horizontal fixture branch column, and for stacks both the total and the per-branch-interval limits (branches of the building drain use Table 710.1(1)) |
| Individual and branch vents | Section 906.2: at least half the required diameter of the drain served, not less than 1-1/4 in, and one size larger for the whole length where the developed length exceeds 40 ft |
| Stack vents and vent stacks | Table 906.1, from the stack size, the dfu on the stack and the developed length of the vent |
| Trap-to-vent distance | Table 909.1, from the trap size and slope |
| Head pressure | 0.433 psi per foot of water; 2.31 ft of water per psi |
| Water supply friction | Pressure left for friction = static pressure minus meter and other device losses, elevation loss and the flow pressure the fixture needs; allowable loss per 100 ft = pressure left x 100 / equivalent length in feet |
| Gas pipe sizing | Longest length method (IFGC Section 402.4.1): each section is sized from the capacity table for the gas, pipe material, pressure and pressure drop, at the length from the point of delivery to the most remote outlet, for that section’s load in the table’s units |
| Combustion air | IFGC Section 304: 50 cu ft of room volume per 1,000 Btu/h (standard method), or 1 sq in of free opening area per 1,000, 2,000, 3,000 or 4,000 Btu/h of total input depending on the arrangement, with the minimums each method sets |
| Offsets | Travel = set x 1.414 (45 degrees), x 1.155 (60 degrees), x 2.000 (30 degrees) |
These are summaries in our own words with the section to look up. The exact rules, exceptions and table values are in the 2024 IPC and IFGC, which the International Code Council lets anyone read free online.
The tables you will open most
An open-book exam rewards knowing which table answers which kind of question. These are 2024 IPC and IFGC tables our own practice questions send candidates to. Tab them before the exam, with permanent tabs if your bulletin allows them.
| Table | What it answers |
|---|---|
| IPC Table 308.5 | Hanger and support spacing for each pipe material, horizontal and vertical |
| IPC Table 403.1 | The minimum number of water closets, lavatories, drinking fountains and service sinks by occupancy |
| IPC Tables 604.4 and 604.5 | Maximum flow rates of fixtures and fittings, and minimum fixture supply pipe sizes |
| IPC Table 608.1 | Which backflow preventer suits which hazard (high or low) and which condition (backpressure or backsiphonage) |
| IPC Table 704.1 | Minimum slope of horizontal drainage pipe by size |
| IPC Table 706.3 | Which drainage fittings may be used for each change of direction |
| IPC Tables 709.1, 710.1(1) and 710.1(2) | Drainage fixture units, and the size of building drains, sewers, branches and stacks |
| IPC Tables 906.1, 909.1, 911.3, 912.3 and 915.2.2 | Stack vent and vent stack size, trap-to-vent distance, common vent, wet vent and combination waste and vent sizes |
| IFGC Tables 402.4(1) onward and Table 415.1 | Gas pipe capacity by size and length (one table for each gas, material, pressure and pressure drop), and gas piping support spacing |
FreeTests: Area 4: Water supply · Area 5: Drains and sewers · Area 6: Vents
Journeyman Plumber Practice Test: free sample
Answer 3 questions against the clock, like the real exam. You then see the right answer, the reason and your time on each. About 8 minutes · free · no sign-in.
3 questions to answer▶ Start nowThis one is free · no sign-in neededYour result shows how long each question took you.Traps that cost marks
- Required versus installed size. Individual, branch and circuit vents (Section 906.2) are sized from the size the drain is required to be, not a larger size someone installed; stack vents and vent stacks are sized from Table 906.1, and relief vents for stacks of more than ten branch intervals follow Section 908.
- Developed length is along the pipe. Add every leg and the travel of offsets; the straight-line distance between the ends is not the developed length.
- Slope changes the drain table. The allowable load can change with slope, so read Table 710.1(1) in the column for the slope given.
- Stacks have two limits. Check both the total dfu and the dfu per branch interval.
- Gas branches use the longest length. Under the longest length method a short branch is still sized at the full length to the most remote outlet.
- Units. Water supply fixture units are not gallons per minute, and a gas load must be in the units of the table you read: natural gas tables are in cubic feet per hour, so divide Btu/h by the gas heating value first.
What each area of the outline asks
The published Oklahoma outline gives the number of questions in each area. The bar chart below shows how the ProSyllabus practice test spreads its own questions over the same areas: our counts, not an exam’s.
ProSyllabus practice test: 249 questions, including a full mock of 85 and a sizing and calculations set. Our counts, not the weighting of any exam.
| Fact | Published exam (Oklahoma) | ProSyllabus mock |
|---|---|---|
| Questions | 85, plus up to ten unscored | 85 in the full mock, split by area as the bulletin lists; outside the mock, a set for each area and a sizing and calculations set of 34 questions |
| Time | 180 minutes | 180 minutes for the full mock |
| Pass mark | 70% correct from 1 November 2026 | Your score by area on our questions; it does not predict an exam result |
| Code edition | IPC and IFGC with Oklahoma revisions; the 2024 editions allowed from 8 October 2026, the 2018 editions no longer allowed as of 14 December 2026 (bulletin) or after 8 January 2027 (Board notice); the two disagree, so confirm the date with the Board before booking | IPC 2024 and IFGC 2024, avoiding every provision Oklahoma amended |
| Answers explained | A diagnostic report if you do not pass | Every answer, with the code section behind it and every sizing problem worked line by line |
Want the full practice test?
The ProSyllabus journeyman plumber practice test has a full mock of 85 questions with a 180-minute clock, a sizing and calculations set and a set for each of the 10 outline areas, your score by area and the code sections to reread. Three questions are free, including the two above; the rest is paid. It is written on the 2024 IPC and IFGC for candidates whose state exam uses those codes. Our own questions, not made or endorsed by PSI, any state board or the ICC. For the exam format and code-book rules, see the journeyman plumber exam guide.
Frequently asked questions
Can I get real journeyman plumber exam questions?
The official sources read for this guide contain none. Practise on questions written from the code and edition your state uses, with your own code book open.
Are these real exam questions?
No. They are ProSyllabus’s own questions, written from the 2024 IPC. Nothing here comes from a PSI or state exam.
How many calculation questions are on the exam?
Outlines differ by state. The Oklahoma outline names calculation topics inside several areas, such as head pressure, area and volume, friction loss and job costs in general knowledge, developed length in vents, gas pipe sizing and cost estimates in fuel gas, and a separate isometric analysis area.
Should I memorize the plumbing code?
Not word for word. The Oklahoma exam described here is open book; check your licensing authority’s rules. Learn where the rules and tables are, and practise the common sizing methods until they are automatic.
Will passing the ProSyllabus mock mean I pass the exam?
No. A practice score is not an exam result and does not predict one. The questions are ours, not an exam’s.
More in this series
Sources
- official — Oklahoma Construction Industries Board: PSI Candidate Information Bulletin (effective 11 Sep 2026)
- official — Oklahoma Construction Industries Board: 2026 Building Code Updates and Examination Transition Period (31 Aug 2026)
- official — International Code Council: 2024 International Plumbing Code, free read-only access
- official — International Code Council: 2024 International Fuel Gas Code, free read-only access
- official — 29 CFR Part 1926, Safety and Health Regulations for Construction (eCFR)
official = a document published by the conducting body. reported = a news or coaching site we could not check against an original. Where sources disagree this page says so rather than picking one.
FreeTests: Area 4: Water supply · Area 5: Drains and sewers · Area 6: Vents
Journeyman Plumber Practice Test: free sample
Answer 3 questions against the clock, like the real exam. You then see the right answer, the reason and your time on each. About 8 minutes · free · no sign-in.
3 questions to answer▶ Start nowThis one is free · no sign-in neededYour result shows how long each question took you.
