Idaho Plumbing Journeyman Exam
Outline update: PSI's Idaho candidate information bulletin effective July 9, 2026 restructured this exam. The 100 questions now cover the 2015 Uniform Plumbing Code, Chapters 3 through 12 (75 questions), plus a 25-question section on Idaho's amendments to that code as printed in the 2017 Idaho State Plumbing Code. Chapters 1, 2 and 13 through 17 are no longer listed, and the two schematic sizing questions were removed. Either the 2015 UPC or the 2017 ISPC may be brought into the test center (open book).
This practice exam was rebuilt to the new outline on September 14, 2026.
Practice at the real exam's pace
Every practice exam shows your time per question against the real exam's clock (1:48 here), and each topic lands in one of these:
What's on the exam
Questions per topic, out of 100Topics
2015 Uniform Plumbing Code Chapter 3
Key Concepts
Material standards, listing, and marking - Pipe, pipe fittings, traps, fixtures, material, and devices must be listed or labeled (third-party certified) by a listing agency and be free from defects (Section 301.2). - Each length of pipe and each fitting, trap, fixture, material, and device must have the manufacturer's mark or name cast, stamped, or indelibly marked on it, done by the manufacturer. "Field markings shall not be acceptable." Exception: markings are not required on nipples created from cutting and threading of approved pipe (Section 301.2.1). - Plastic pipe, fittings, and components other than those for gas shall comply with NSF 14 (Section 301.2.3). Cast-iron soil pipe and hubless couplings shall be third-party certified per ASTM C1277 and CISPI 310 (Section 301.2.4).
2015 Uniform Plumbing Code Chapter 4
Citations follow the SOURCE. All section numbers below are the 2017 ISPC numbers used by the verified questions. The 2015 UPC Chapter 4 text in the SOURCE covers only Sections 401.0 through 407.2; within that range Sections 402.5 and 405.2 read the same as the 2017 ISPC, while 401.2 differs (the UPC adds a reference to Table 1701.1). The SOURCE does not show 2015 UPC text for Sections 408.0 and beyond.
Key Concepts
Setting and clearances (Section 402.5) - No water closet or bidet closer than 15 inches (381 mm) from its center to a side wall or obstruction. - No water closet or bidet closer than 30 inches (762 mm) center to center to a similar fixture. - Clear space in front of a water…
2015 Uniform Plumbing Code Chapter 5
Key Concepts
Permits and inspection - It is unlawful to install, remove, or replace a water heater without first obtaining a permit from the Authority Having Jurisdiction (Section 502.1). - Chimney/vent inspection occurs after installation and before the vent is covered or concealed. Under the 2017 ISPC, water heating appliances using Category 3 or 4 exhaust venting shall be tested in their entirety with 5 pounds of air for 15 minutes (Section 503.1). No appliance may be concealed before inspection and approval (Section 503.2).
Location and clearance - Water heaters in bedrooms/bathrooms must either be in a closet with a listed gasketed door assembly and listed self-closing device (combustion air from outdoors per Section 506.4, closet for exclusive use of the water heater) or be direct-vent…
2015 Uniform Plumbing Code Chapter 6
Key Concepts
System identification (601.3) - Potable water: green background with white lettering (601.3.1). - Nonpotable water: yellow background with black uppercase lettering, words "CAUTION: NONPOTABLE WATER, DO NOT DRINK"; flow direction shown; markings every 20 feet but not less than once per room, visible from floor level (601.3.2). Letter size and color-field length per Table 601.3.2. - Alternate water sources: purple (Pantone No. 512, 522C, or equivalent) background with uppercase lettering; reclaimed (recycled) water marked "CAUTION: NONPOTABLE RECLAIMED (RECYCLED) WATER, DO NOT DRINK" in black letters (601.3.3).
Materials and lead content (604.0) - Lead: 0.25 percent weighted average of wetted surfaces for pipe, pipe fittings, plumbing fittings, and fixtures conveying water for human consumption; 0.2 percent for solder and flux (604.2). Non-drinking water applications: maximum…
2015 Uniform Plumbing Code Chapter 7
Idaho Plumbing Journeyman Exam
Key Concepts
Material restrictions by location (Sec. 701.2) - Galvanized wrought-iron or galvanized steel: not used underground; kept not less than 6 inches aboveground — 701.2(1). - Stainless steel 304: not installed underground; kept not less than 6 inches aboveground — 701.2(5). - Vitrified clay: not used aboveground or where pressurized by a pump or ejector; kept not less than 12 inches belowground — 701.2(3). - Copper/copper alloy tube for drainage and vent: weight not less than type DWV — 701.2(4). - ABS/PVC DWV exposed in ducts or plenums (except individual single-family dwelling units): flame-spread index not more than 25, smoke-developed index not more than 50, per ASTM E84 or UL 723 — 701.2(2). - No portion of drainage or vent underground,…
2015 Uniform Plumbing Code Chapter 8
Key Concepts
Air gap / air break (Section 801.2). Indirect waste piping shall discharge into the building drainage system through an air gap or air break. Where a drainage air gap is required, the minimum vertical distance from the lowest point of the indirect waste pipe or the fixture outlet to the flood-level rim of the receptor shall be not less than 1 inch (25.4 mm).
Food and beverage establishments (Section 801.3). Indirect waste piping is required for refrigerators, refrigeration coils, freezers, walk-in coolers, iceboxes, ice-making machines, steam tables, egg boilers, coffee urns and brewers, hot-and-cold drink dispensers, and similar equipment.
2015 Uniform Plumbing Code Chapter 9
Idaho Plumbing Journeyman Exam — Chapter 9: Vents
Key Concepts
General requirements - Each plumbing fixture trap, except as otherwise provided, shall be protected against siphonage and backpressure, and air circulation shall be ensured throughout all parts of the drainage system by means of vent pipes (Section 901.2). - The vent system shall be designed to prevent a trap seal from being exposed to a pressure differential exceeding 1 inch water column (0.24 kPa) on the outlet side of the trap (Section 901.3). An engineered vent system must also meet Section 901.3 (Section 912.2).
Materials - No galvanized steel or 304 stainless steel pipe shall be installed underground; it shall be not less than 6 inches aboveground (Section 903.1(1)).
2015 Uniform Plumbing Code Chapter 10
Key Concepts
Where traps are required (Section 1001.2). Each plumbing fixture shall be separately trapped by an approved type of liquid seal trap; this does not apply to fixtures with integral traps. Not more than one trap is permitted on a trap arm. Food waste disposers installed with a set of restaurant, commercial, or industrial sinks shall be connected to a separate trap. Each domestic clothes washer and each laundry tub shall be connected to a separate and independent trap, except that a trap serving a laundry tub may also receive the waste from a clothes washer set adjacent thereto. The vertical distance between fixture outlet and trap weir shall be as short as practicable, but the tailpiece shall not exceed 24 inches (610 mm). One…
2015 Uniform Plumbing Code Chapter 11
Key Concepts
- Storm water to sanitary sewer is prohibited. Storm water shall not be drained into sewers intended for sanitary drainage (Section 1101.3). Roofs, paved areas, yards, courts, vent shafts and similar areas shall drain to a separate storm sewer, or to a combined sewer where no separate storm sewer is available (Section 1101.2).
- Materials — conductors in a vent or shaft: cast-iron, galvanized steel, wrought iron, copper, copper alloy, lead, Schedule 40 ABS DWV, Schedule 40 PVC DWV, or stainless steel 304 or 316L (Section 1101.4). Stainless steel 304 shall not be installed underground and shall be kept not less than 6 inches (152 mm) aboveground.
- Materials — outside leaders: standards referenced in Table 701.2 for aboveground DWV pipe, plus aluminum sheet…
2015 Uniform Plumbing Code Chapter 12
Key Concepts
Scope and coverage - Chapter 12 governs fuel gas piping in or in connection with a building, structure, or within the property lines of premises up to 5 psi (34 kPa), other than service pipe; fuel oil piping follows NFPA 31 (§1201.1). - Coverage extends from the point of delivery to the appliance connections (§1202.1). - Maximum design operating pressure inside buildings shall not exceed 5 psi unless a listed condition is met — e.g., the piping is welded, piping in a ventilated chase, industrial/boiler rooms, temporary installations, agricultural uses (UPC §1210.5).
2017 Idaho State Plumbing
Key Concepts
Testing & inspection. No test or inspection is required where a plumbing system, or part thereof, is set up for exhibition purposes and has no connection with a water or drainage system (Section 105.3 as amended; IDAPA 24.39.20, Section 600.01(b), Page 7). Idaho deletes the phrases prohibiting air testing of plastic DWV piping (Sections 712.1 and 723.0; IDAPA 24.39.20, Sections 600.38 and 600.40, Page 10).
Fixtures. Fixtures must be dense, durable, non-absorbent, with smooth, impervious surfaces free from unnecessary concealed fouling surfaces (Section 401.2; IDAPA 24.39.20, Section 600.03, Page 7). Shower receptor floors slope uniformly from the sides toward the drain not less than 1/8 inch per foot (10.4 mm/m) nor more than 1/2 inch per foot (41.8 mm/m) (Section 408.5). Deleted sections: 403.3…