ICC G24 Master Plumber Exam (2018 IPC)
Practice at the real exam's pace
Every practice exam shows your time per question against the real exam's clock (2:24 here), and each topic lands in one of these:
What's on the exam
Questions per topic, out of 100Topics
Administration General Regulations
Key Concepts
Scope & existing work (Ch. 1) - The IPC governs plumbing systems; detached one- and two-family dwellings and townhouses not more than three stories high with separate means of egress and their accessory structures comply with the IRC (§101.2 Exception). - Additions, alterations, renovations or repairs related to building or structural issues are regulated by the International Existing Building Code (§102.2.1). - Devices or safeguards required by the code shall be maintained in compliance with the edition of the code under which they were installed (§102.3). - The code official may appoint deputies, technical officers and inspectors, who have powers as delegated by the code official (§103.3).
Approval and testing authority - Where evidence of compliance is insufficient, tests are required at no expense to the jurisdiction (§105.3) and shall be performed by an approved agency (§105.3.2).
Permits and fees - Exempt work includes clearing stoppages, repairing leaks in pipes, valves or fixtures, and removal/reinstallation of water closets, provided no replacement or rearrangement of valves, pipes or fixtures is required; replacing a defective concealed drainpipe requires a permit (§106.2). - Construction documents for buildings more than two stories in height must indicate penetration locations and the materials/methods…
Plumbing Fixtures
Chapter 4 Fixtures, Faucets and Fixture Fittings; Chapter 5 Water Heaters
Key Concepts
Minimum facilities and separate facilities - Fixture counts come from Table 403.1, based on actual use; occupant load is determined by the IBC (403.1). - To find the occupant load of each sex, divide the total occupant load in half; apply the ratio to each sex; fractional results are rounded up; for multiple occupancies, sum the fractions first, then round up (403.1.1). - Separate facilities are required for each sex, with exceptions: dwelling/sleeping units; occupant load (employees + customers) of 15 or fewer; mercantile 100 or fewer; business 25 or fewer (403.2, Exceptions 1–4). - Public toilet facilities are not required for unattended parking garages or for quick-transaction spaces (takeout, pickup, drop-off) with public access area ≤ 300 square feet (403.3, Exception 2). - Travel to required toilet facilities: not more than 500 feet and not more than one story above/below in occupancies other than malls (403.3.3); not more than 300 feet in covered/open malls, measured from the main entrance of the store or tenant space (403.3.4).
Water Supply and Distribution
Key Concepts
Service and distribution sizing/pressure - Water service pipe shall be sized for required quantities and pressures, but in no case less than 3/4 inch (19.1 mm) in diameter — Section 603.1. - Water service pipe or tubing installed underground and outside the structure shall have a working pressure rating of not less than 160 psi (1100 kPa) at 73.4°F (23°C) — Section 605.3. Water service piping materials not third-party certified for water distribution shall terminate at or before the full-open valve at the entrance to the structure — Section 605.3. - Hot water distribution pipe and tubing shall have a pressure rating of not less than 100 psi (690 kPa) at 180°F (82°C) — Section 605.4. - Water service/building sewer separation: where the sewer is not of listed building-sewer materials, the 5-foot horizontal separation is waived if the bottom of the water service pipe, within 5 feet of the sewer, is not less than 12 inches (305 mm) above the highest point of the top of the building sewer — Section 603.2. - Fixture supply pipe shall terminate not more than 30 inches from the point of connection to the fixture — Section 604.5.
Sanitary Drainage
Key Concepts
Slope of horizontal drainage piping (704.1, Table 704.1). Horizontal drainage piping shall be installed in uniform alignment at uniform slopes, not less than indicated in Table 704.1. Pipe 3 inches to 6 inches requires not less than 1/8 inch per foot. Exception: where the drainage piping is upstream of a grease interceptor, the slope shall be not less than 1/4 inch per foot (2-percent slope).
Reduction in size in direction of flow (704.2). Drainage piping shall not be reduced in the direction of flow. Not considered reductions: (1) a 4-inch by 3-inch water closet flange; (2) a water closet bend fitting with a 4-inch inlet and 3-inch outlet where the 4-inch leg is upright and below the flange; (3) an offset closet flange.
Connections at bases of stacks (704.3). Horizontal branches shall connect to the bases of stacks at a point not less than 10 times the diameter of the drainage stack downstream from the stack. The same 10-diameter rule applies downstream of the upper stack at horizontal stack offsets.
Plumbing Vent Requirements
Key Concepts
Vent connections and grades (Section 905) - Vent and branch vent pipes shall be graded and connected to drain back to the drainage pipe by gravity (905.2). - Every dry vent connecting to a horizontal drain shall connect above the centerline of the horizontal drain pipe (905.3). - Every dry vent shall rise vertically to a point not less than 6 inches (152 mm) above the flood level rim of the highest trap or trapped fixture being vented. Exception: vents for interceptors located outdoors (905.4). - A connection between a vent pipe and a vent stack or stack vent shall be made not less than 6 inches above the flood level rim of the highest fixture served; horizontal branch, relief or loop vents are likewise not less than 6 inches above that rim (905.5). - Where drainage is roughed-in for future fixtures, a vent rough-in shall be installed not less than one-half the diameter of the rough-in drain served, and the connection shall be identified as a vent (905.6).
Traps, Interceptors, and Separators
Key Concepts
Fixture traps (Section 1002.1, IPC 2018 Ch. 10). Each plumbing fixture shall be separately trapped by a liquid-seal trap. The vertical distance from the fixture outlet to the trap weir shall not exceed 24 inches (610 mm) — a maximum — and the horizontal distance shall not exceed 30 inches (762 mm), measured centerline of fixture outlet to centerline of trap inlet. A fixture shall not be double trapped. Exceptions include integral traps; a combination plumbing fixture on one trap where one compartment is not more than 6 inches (152 mm) deeper than the other and waste outlets are not more than 30 inches (762 mm) apart; and multilevel parking structure floor drains.
Grease interceptor as a fixture trap (Section 1002.1, Exception 3). Permitted for a single fixture or a combination sink of not more than three compartments where the vertical distance from fixture outlet to interceptor inlet does not exceed 30 inches (762 mm) and the developed length of waste pipe from the most upstream fixture outlet to the interceptor inlet does not exceed 60 inches (1524 mm).
Storm Drainage
Key Concepts
Scope and disposal - Chapter 11 governs the materials, design, construction and installation of storm drainage (§1101.1). - Rainwater from roofs and storm water from paved areas, yards, courts and courtyards shall drain to an approved place of disposal. For one- and two-family dwellings, and where approved, storm water is permitted to discharge onto flat areas such as streets or lawns, provided the storm water flows away from the building (§1101.2). - Storm water shall not be drained into sewers intended for sewage only (§1101.3). - The size of a drainage pipe shall not be reduced in the direction of flow (§1101.5). - Conductors and the building storm drain shall be tested in accordance with Section 312 (§1101.4). Cleanouts are required in the storm drainage system, with an exception for subsurface drainage systems (§1101.8). Backwater valves are required as for sanitary drainage per Section 714 (§1101.9).