Exam Cheat Sheet · Quick Reference
ICC G25 Journeyman Plumber Exam (2018 IPC)
National · Pearson Vue
Verified, not estimated. Every figure below is drawn from the official exam structure we maintain — question counts, passing standard and topic weighting. Practice questions are grounded in the source law with statute citations. We omit any figure we can't verify rather than guess at it.
Total questions
70
Passing score
70%
Exam time
240 min
Administered by
Pearson Vue
Format
Reference materials allowed
National State Portion 70 questions
Administration General Regulations
28 Q · 40%
General Installation RequirementsCode Definitions and TermsPlan ReadingTestingMaterialsPermits: application, issuance, expiration, and exemptionsInspection types and sequencing (underground, rough-in, final)Code official authority, duties, and enforcement powersViolations, stop work orders, and unsafe plumbing abatementMeans of appeal and board of appeals proceduresPipe protection requirements (freezing, physical damage, corrosion, rodentproofing)Trenching, bedding, and backfill requirements
+4 more
Plumbing Fixtures
12 Q · 17%
Water HeatersWater Closets and UrinalsSpecialty FixturesMinimum number of plumbing fixtures by occupancy typeFixture installation requirements and spacing clearancesFaucets, shower valves, and temperature-limiting devicesFixture material standards and quality requirementsFlushing devices for water closets and urinalsBathtubs, showers, and whirlpool bathtubsWater heater safety devices and relief valvesSeparate toilet facilities and accessible fixture requirementsChapter 4 Fixtures, Faucets and Fixture Fittings
Water Supply and Distribution
10 Q · 14%
Service Distribution and PipingWater Supply and PressureProtection of Potable Water SupplyPipe Materials, Fittings, and Jointing MethodsHot Water Supply System RequirementsValve Installation and Location RequirementsWater Hammer and Pressure RegulationWater System Disinfection ProceduresWater Pressure Booster Systems and Storage TanksIndividual Water Supply Systems and Well ConstructionChapter 6 Water Supply and Distribution
Sanitary Drainage
9 Q · 13%
Building Sanitary DrainageSumps and EjectorsIndirect and Special Waste SystemsDrainage pipe materials and applicable standards (above-ground, underground, and building sewer)Drainage pipe joints and connection methods by material typeSlope, sizing, and fixture unit load calculations for drainage systemsCleanout requirements, placement, sizing, and accessDrainage fittings for changes in direction and prohibited connectionsBackwater valves — application, material, and location requirementsStack offsets in buildings of five or more storiesVacuum drainage systems and pipe-bursting replacement methodsChapter 7 Sanitary Drainage
Plumbing Vent Requirements
5 Q · 7%
Vent Connections and GradesVent TerminalsVent Pipe Sizing and Developed LengthIndividual, Common, and Wet Venting MethodsAir Admittance ValvesFixture Trap Distance from VentRelief Vents and Stack Offset VentingOutdoor Vent Extensions and Vent Stack Requirements
Traps, Interceptors, and Separators
5 Q · 7%
Installation of TrapsInterceptors and SeparatorsTrap seal requirements and dimensionsProhibited trap typesTrap seal protection methods and primer devicesTrap sizing and design requirementsGrease interceptor capacity and flow-through ratingsOil separator design and capacity requirementsSand, solids, and specialty interceptors (clothes washer, bottling, slaughterhouse)Venting and access requirements for interceptors and separators
Storm Drainage
1 Q · 1%
Storm DrainageSizing of vertical conductors, leaders, and horizontal storm drains using 100-year rainfall ratesPrimary and secondary (emergency overflow) roof drain requirements and scupper sizingPermitted materials for storm drain conductors, building storm sewer pipe, and subsoil drain pipeRoof drain installation requirements and flow rate calculationsProhibited connections and disposal requirements for storm waterStorm drainage traps: when required, sizing, and cleanout provisionsSiphonic roof drainage system requirementsHorizontal gutter sizing and parapet wall scupper requirements
Key Distinctions
Stack ventvsVent stack
A stack vent is the extension of a soil or waste stack above the highest horizontal drain connected to that stack, while a vent stack is a vertical vent pipe installed primarily to provide circulation of air to and from the drainage system.
IPC 2018 Chapter 2 — Section 202, definitions of Stack Vent and Vent StackHorizontal pipevsVertical pipe
A horizontal pipe or fitting makes an angle of less than 45 degrees with the horizontal plane; a vertical pipe or fitting makes an angle of 45 degrees or more with the horizontal (so piping at 40 degrees is horizontal pipe).
IPC 2018 Chapter 2 — Section 202, definitions of Horizontal Pipe and Vertical PipePlumbing appurtenancevsPlumbing appliance
A plumbing appurtenance is an adjunct device that demands no additional water supply and adds no discharge load to a fixture or the drainage system, whereas devices dependent on energized components are plumbing appliances.
IPC 2018 Chapter 2 — Section 202, definitions of Plumbing Appurtenance and Plumbing ApplianceS-trapvsDrum trap
Both are prohibited traps, but the S-trap is prohibited with no exception, while drum traps have an exception permitting their use as solids interceptors and for chemical waste systems.
IPC 2018 Section 1002.3Full-open valve (Section 606.1)vsShutoff valve (Section 606.2)
Full-open valves are required at locations such as the discharge side of every water meter, the water supply pipe to every water heater, the entrance to the structure, and the base of every water riser pipe (in occupancies other than multiple-family residential two stories or less and one- and two-family dwellings); shutoff valves — not full-open valves — are required at fixture supplies.
IPC 2018 Sections 606.1 and 606.2Urinal substitution in assembly and educational occupanciesvsUrinal substitution in all other occupancies
Urinals shall not be substituted for more than 67 percent of required water closets in assembly and educational occupancies, but not more than 50 percent in all other occupancies.
IPC 2018 Section 424.2Separate-facility Exception 2 threshold (15 occupants)vsSeparate-facility Exception 4 threshold for business occupancies (25 or fewer)
The general exception threshold is an occupant load of 15, while Exception 4 waives separate facilities in business occupancies with a maximum occupant load of 25 or fewer; at an occupant load of 30 neither exception applies and separate facilities for each sex are required.
IPC 2018 Section 403.2 Exception 4Potable water-supplied trap seal primer valve (ASSE 1018)vsWaste water-supplied trap primer device (ASSE 1044) / barrier-type trap seal protection device (ASSE 1072)
Potable water-supplied trap seal primer valves conform to ASSE 1018 (1002.4.1.1), waste water-supplied trap primer devices conform to ASSE 1044 (1002.4.1.3), and barrier-type trap seal protection devices conform to ASSE 1072 (1002.4.1.4).
IPC 2018 Section 1002.4.1.1Tempered watervsHot water
Tempered water has a temperature range between 85°F and 110°F; water at 110°F or greater is defined as hot water.
IPC 2018 Section 202 — definition of 'Tempered Water' (Chapter 2 Definitions)General floor drain outlet (Section 413.3)vsFloor drains in rooms with automatic clothes washers in public laundries and multiple-family central washing facilities (Section 413.4)
The general minimum floor drain outlet is 2 inches, but rooms containing automatic clothes washers in public coin-operated laundries and central washing facilities of multiple-family dwellings require floor drains with an outlet of not less than 3 inches in diameter.
IPC 2018 Chapter 4 — Section 413.4 Public Laundries and Central Washing FacilitiesFixtures required to discharge through a grease interceptorvsFood waste disposer
Pot sinks, prerinse sinks, and floor drains into which kettles are drained are required to discharge through a grease interceptor (1003.3.1), but a food waste disposer shall not discharge to a grease interceptor (1003.3.2).
IPC 2018 Section 1003.3.2Water service pipe/tubing installed underground and outside the structurevsHot water distribution pipe and tubing
Underground exterior water service pipe must have a working pressure rating of not less than 160 psi at 73.4°F, while hot water distribution pipe must have a pressure rating of not less than 100 psi at 180°F.
IPC 2018 Section 605.3Tests required by the code official as evidence of compliance (105.3)vsPlumbing system tests under Sections 312/107.4
Tests required where there is insufficient evidence of product compliance are performed by an approved agency at no expense to the jurisdiction, whereas the permit holder makes the plumbing system tests required by 312/107.4.
IPC 2018 Chapter 1 — Sections 105.3 and 105.3.2 Required Testing/Testing AgencyKey Terms
Backflow, low head backpressure IPC 2018 Chapter 2 — Section 202, definition of Backflow (Backpressure, low head)
A pressure less than or equal to 4.33 psi (29.88 kPa), or the pressure exerted by a 10-foot column of water.
Branch interval IPC 2018 Section 202 — definition of 'Branch Interval' (Chapter 2 Definitions)
A vertical measurement of distance of 8 feet or more in developed length between connections of horizontal branches to a drainage stack, measured down the stack from the highest horizontal branch connection.
Tempered water IPC 2018 Section 202 — definition of 'Tempered Water' (Chapter 2 Definitions)
Water having a temperature range between 85°F (29°C) and 110°F (43°C).
Stack vent IPC 2018 Chapter 2 — Section 202, definitions of Stack Vent and Vent Stack
The extension of a soil or waste stack above the highest horizontal drain connected to the stack.
Vent stack IPC 2018 Chapter 2 — Section 202, definitions of Stack Vent and Vent Stack
A vertical vent pipe installed primarily to provide circulation of air to and from the drainage system.
Plumbing appurtenance IPC 2018 Chapter 2 — Section 202, definitions of Plumbing Appurtenance and Plumbing Appliance
A manufactured device, prefabricated assembly or on-the-job assembly that is an adjunct to the basic piping system and plumbing fixtures, demanding no additional water supply and adding no discharge load to a fixture or to the drainage system.
Approved agency IPC 2018 Chapter 1 — Sections 105.3 and 105.3.2 Required Testing/Testing Agency
The entity that must perform tests required by the code official under Section 105.3 when there is insufficient evidence of compliance, at no expense to the jurisdiction.
Water pressure-reducing valve IPC 2018 Section 604.8
An approved valve conforming to ASSE 1003 or CSA B356 with strainer, required where static water pressure within a building exceeds 80 psi, to reduce pressure to not greater than 80 psi static, and designed to remain open to permit uninterrupted water flow in case of valve failure.
Drum trap IPC 2018 Section 1002.3
A prohibited trap type, excepted only where used as a solids interceptor or where serving chemical waste systems.
Fixture trap liquid seal IPC 2018 Section 1002.4
Each fixture trap shall have a liquid seal of not less than 2 inches and not more than 4 inches, or deeper for special designs relating to accessible fixtures.
Oil separator (garages and service stations) IPC 2018 Section 1003.4.2.2
An interceptor whose outlet opening shall have not less than an 18-inch water seal, sized at not less than 6 cubic feet for the first 100 square feet of area drained plus 1 cubic foot for each additional 100 square feet.
Clothes washer interceptor IPC 2018 Section 1003.6
An interceptor with a wire basket or similar device through which clothes washers discharge, preventing passage into the drainage system of solids 1/2 inch or larger, string, rags, buttons, or other materials detrimental to the public sewage system.
Bottling plant interceptor IPC 2018 Section 1003.7
An interceptor that provides for separation of broken glass or other solids before process waste discharges into the drainage system.
Grease interceptor flow-control device IPC 2018 Section 1003.3.5.2
A device controlling the rate of water flow that shall be vented and terminate not less than 6 inches above the flood rim level, or be installed in accordance with the manufacturer's instructions.
Lead free (solder and flux) IPC 2018 Section 605.13.6
A chemical composition equal to or less than 0.2-percent lead, required for solder and flux used in joining water supply piping.
Water-hammer arrestor IPC 2018 Section 604.9
A device conforming to ASSE 1010, installed where quick-closing valves are utilized and in accordance with the manufacturer's instructions.
Bearing plane of a footing (Section 307.5) IPC 2018 Chapter 3 — Section 307.5 Protection of Footings
The zone whose upper boundary is a line extending downward at 45 degrees from horizontal from the outside bottom edge of the footing or wall; trenching parallel to footings and walls shall not extend into that plane.
Heat-fusion joint (PE pipe) IPC 2018 Section 605.18.2
A joint in which joint surfaces are clean and free from moisture, heated to melt temperature, joined, and left undisturbed until cool, made in accordance with ASTM D2657.
Formulas to Know
Oil separator capacity for garages and service stations (Section 1003.4.2.2)
Capacity = 6 cubic feet for the first 100 sq ft of area drained + 1 cubic foot for each additional 100 sq ft. Worked examples: 500 sq ft → 6 + (4 × 1) = 10 cu ft; 400 sq ft → 6 + 3 = 9 cu ft.Maximum urinal substitution for required water closets (Section 424.2)
Assembly and educational occupancies: max urinals = 67% × required water closets (all other occupancies: 50%). Worked example: 6 required WCs × 0.67 = 4.02 → maximum of 4 may be replaced by urinals.Female water closets required in a restaurant (Table 403.1 with Section 403.1.1)
Female occupant load = total occupant load ÷ 2; then required WCs = female load ÷ 75 (restaurant ratio 1 per 75 for females). Worked example: 150 ÷ 2 = 75; 75 ÷ 75 = 1 water closet.Handling fractional fixture counts for multiple occupancies (Section 403.1.1)
Fractional numbers from fixture ratios are rounded up to the next whole number; for multiple occupancies, sum the fractional numbers for each occupancy first, then round up.Urinal privacy partition extension from finished backwall (Section 405.3.5)
Extend the greater of: 18 inches from the wall surface at each side, OR (outermost front lip projection + 6 inches) measured from the finished backwall surface. Worked example: 14 in lip + 6 = 20 in > 18 in, so 20 inches.Grease retention capacity for hydromechanical interceptors over 100 gpm (Table 1003.3.5.1 footnote a)
For total flow-through ratings greater than 100 gpm, grease retention capacity in pounds = 2 × flow-through rating (the 30-minute multiplier applies instead to sizing gravity grease interceptors under Section 1003.3.7).Low head backpressure equivalent (Section 202)
Low head backpressure ≤ 4.33 psi (29.88 kPa) = pressure exerted by a 10-foot column of water.Threaded CPVC pressure rating (Section 605.14.3)
Threaded CPVC pressure rating = rated pressure reduced by 50 percent; pipe wall thickness must be not less than Schedule 80.Minimum bending radius for PE water service pipe (Section 605.18.4)
Minimum bend radius = not less than 30 pipe diameters, or the minimum coil radius, whichever is greater.Sectional water test of drainage and vent system (Section 312.2)
Each section tested with not less than a 10-foot head of water, including not less than the upper 10 feet of the next preceding section, so no joint or pipe except the uppermost 10 feet is tested with less than a 10-foot head; hold pressure not less than 15 minutes.