ND Journeyman Plumber cheat sheet

A plumbing permit is required before installing, altering, or replacing most plumbing systems; permits are issued by the local authority having jurisdiction (AHJ), and inspections must be requested at required stages.

Standard inspections typically include rough-in (before concealment), water supply and DWV pressure/head tests, and final inspection after fixtures are set and tested.

A test on the drainage system is commonly a water test with 10 ft (3 m) of head at the highest point, or an air test at 5 psi (34.5 kPa) held for 15 minutes with no drop.

A water distribution system is tested at working pressure or a minimum of 100 psi (690 kPa) for at least 15 minutes, or per the adopted code's specified test.

Code editions are adopted locally; the applicable edition is whichever the AHJ has adopted, so confirm the edition and local amendments rather than assuming a model code year.

A journeyman plumber works under a licensed master or contractor; scope of work allowed without supervision varies by jurisdiction and license class.

Common code definitions: fixture unit (drainage/fixture load), developed length (measured along the pipe run including fittings), and trap seal depth (typically 2 to 4 in.).

Vent termination must be at least 6 in. above the roof surface and not less than 3 ft from a window, door, or air intake opening, unless local code states otherwise.

Where a code requirement and a manufacturer's installation instruction conflict, the more restrictive requirement generally governs; manufacturer instructions must be followed for listed appliances.

A water closet's water consumption is rated in gallons per flush (gpf); current standard tank-type fixtures are typically 1.28 gpf, with high-efficiency models at 1.28 gpf or less.

Fixture clearances: a water closet requires at least 15 in. from its centerline to any side wall and 21 in. of clear space in front of the bowl.

A lavatory requires at least 15 in. of clearance from centerline to a side wall and 21 in. from the front edge to a facing wall.

Fixture drain trap seal: each fixture needs its own trap, with a liquid seal of 2 to 4 in. depth; a trap must be accessible for cleaning.

An air gap or an air gap device provides the highest level of backflow protection at a fixture; a vacuum breaker is used where a hose connection or submerged inlet is possible.

A water heater temperature and pressure relief (TPR) valve discharge pipe must be full size, gravity-drained, terminate 6 to 24 in. above the floor or outside, and never be capped or reduced.

Fixture units: a water closet is typically 3 fixture units (drainage), a lavatory 1, a bathtub 2, and a kitchen sink 2, per the standard fixture unit table.

A floor drain requires a trap and a trap primer or other means to maintain the seal where evaporation can occur.

Minimum static pressure at a fixture is typically 8 psi (55 kPa) for a flush tank and 15 psi (103 kPa) for a flushometer valve; maximum pressure in the distribution system is 80 psi.

Where pressure exceeds 80 psi, a pressure-reducing valve is required; a thermal expansion tank is needed on a closed system to absorb expansion from heating.

Water service pipe sizing uses the fixture-unit method: total demand fixture units, developed length, and available pressure determine the pipe size from tables.

Developed length includes the actual pipe run plus an allowance for fittings; use the equivalent-length table for elbows, tees, and valves.

Common water pipe materials: copper (Type L for underground, Type M for interior), PEX, CPVC, and galvanized steel; each has a maximum temperature and pressure rating that must not be exceeded.

Shutoff valves: a main shutoff at the service entry, a valve on each fixture branch, and a valve on the water heater cold inlet and hot outlet.

Hot water distribution: hot water should be drawn on the left and cold on the right; the water heater should be located close to the fixtures to reduce wait time and wasted water.

Backflow prevention: a reduced-pressure-zone (RPZ) assembly is required where a cross-connection with a high hazard exists, and it must be tested annually.

Drainage pipe slope: 2 in. and smaller drains at 1/4 in. per ft; 3 in. at 1/8 in. per ft; 4 in. and larger at 1/8 in. per ft, unless the code specifies otherwise.

A building drain is the lowest pipe receiving soil and waste inside the building; it becomes the building sewer when it exits the foundation.

A trap arm length is limited by pipe size: 1-1/4 in. trap arm 5 ft, 1-1/2 in. 6 ft, 2 in. 8 ft, 3 in. 12 ft, 4 in. 16 ft, measured to the vent.

Each trap requires a vent; a vent must rise vertically at least 6 in. above the fixture's flood-level rim before offsetting horizontally.

A wet vent may serve only fixtures on the same floor and must be sized per the vent table; a dry vent is a vent that carries no waste.

A cleanout is required at the base of a stack, at the building drain, at changes of direction greater than 45 degrees, and at intervals not exceeding 100 ft in horizontal runs.

A backwater valve is required where a fixture is below the level of the public sewer or where the sewer can back up into the building.

Vent stack and stack vent sizing depends on the total fixture units and the developed length; an undersized vent causes slow drainage and gurgling.

Before soldering or brazing, purge the line and remove all combustible material; a fire watch and a fire extinguisher are required where open flame is used.

Confined space entry requires atmospheric testing (oxygen, combustible gas, hydrogen sulfide) and a permit; never enter a sewer or vault without testing and a standby person.

Backflow and cross-connection control protect the potable supply; a hose bibb without a vacuum breaker is a common cross-connection hazard.

Personal protective equipment for plumbing work includes safety glasses, gloves, hearing protection when using a hammer drill, and knee pads for prolonged kneeling.

Common hand tools: pipe wrench (stillson), basin wrench for tight spaces under sinks, tubing cutter, deburring tool, and a spud wrench for fixture work.

A pressure gauge, a manometer, and a leak-detection method (soap solution or electronic detector) are used to test gas and water lines.

A gas leak is detected with a soap-and-water solution or an electronic detector, never with an open flame; shut off the gas before repairs.

Hot work near wood framing requires a heat shield and a minimum clearance from combustibles; a water heater flue must maintain clearance from combustibles per the listing.

A plumbing permit is required before installing, altering, or replacing most plumbing systems; permits are issued by the local authority having jurisdiction (AHJ), and inspections must be requested at required stages.

Standard inspections typically include rough-in (before concealment), water supply and DWV pressure/head tests, and final inspection after fixtures are set and tested.

A test on the drainage system is commonly a water test with 10 ft (3 m) of head at the highest point, or an air test at 5 psi (34.5 kPa) held for 15 minutes with no drop.

A water distribution system is tested at working pressure or a minimum of 100 psi (690 kPa) for at least 15 minutes, or per the adopted code's specified test.

Code editions are adopted locally; the applicable edition is whichever the AHJ has adopted, so confirm the edition and local amendments rather than assuming a model code year.

A journeyman plumber works under a licensed master or contractor; scope of work allowed without supervision varies by jurisdiction and license class.

Common code definitions: fixture unit (drainage/fixture load), developed length (measured along the pipe run including fittings), and trap seal depth (typically 2 to 4 in.).

Vent termination must be at least 6 in. above the roof surface and not less than 3 ft from a window, door, or air intake opening, unless local code states otherwise.

Where a code requirement and a manufacturer's installation instruction conflict, the more restrictive requirement generally governs; manufacturer instructions must be followed for listed appliances.

A water closet's water consumption is rated in gallons per flush (gpf); current standard tank-type fixtures are typically 1.28 gpf, with high-efficiency models at 1.28 gpf or less.

Fixture clearances: a water closet requires at least 15 in. from its centerline to any side wall and 21 in. of clear space in front of the bowl.

A lavatory requires at least 15 in. of clearance from centerline to a side wall and 21 in. from the front edge to a facing wall.

Fixture drain trap seal: each fixture needs its own trap, with a liquid seal of 2 to 4 in. depth; a trap must be accessible for cleaning.

An air gap or an air gap device provides the highest level of backflow protection at a fixture; a vacuum breaker is used where a hose connection or submerged inlet is possible.

A water heater temperature and pressure relief (TPR) valve discharge pipe must be full size, gravity-drained, terminate 6 to 24 in. above the floor or outside, and never be capped or reduced.

Fixture units: a water closet is typically 3 fixture units (drainage), a lavatory 1, a bathtub 2, and a kitchen sink 2, per the standard fixture unit table.

A floor drain requires a trap and a trap primer or other means to maintain the seal where evaporation can occur.

Minimum static pressure at a fixture is typically 8 psi (55 kPa) for a flush tank and 15 psi (103 kPa) for a flushometer valve; maximum pressure in the distribution system is 80 psi.

Where pressure exceeds 80 psi, a pressure-reducing valve is required; a thermal expansion tank is needed on a closed system to absorb expansion from heating.

Water service pipe sizing uses the fixture-unit method: total demand fixture units, developed length, and available pressure determine the pipe size from tables.

Developed length includes the actual pipe run plus an allowance for fittings; use the equivalent-length table for elbows, tees, and valves.

Common water pipe materials: copper (Type L for underground, Type M for interior), PEX, CPVC, and galvanized steel; each has a maximum temperature and pressure rating that must not be exceeded.

Shutoff valves: a main shutoff at the service entry, a valve on each fixture branch, and a valve on the water heater cold inlet and hot outlet.

Hot water distribution: hot water should be drawn on the left and cold on the right; the water heater should be located close to the fixtures to reduce wait time and wasted water.

Backflow prevention: a reduced-pressure-zone (RPZ) assembly is required where a cross-connection with a high hazard exists, and it must be tested annually.

Drainage pipe slope: 2 in. and smaller drains at 1/4 in. per ft; 3 in. at 1/8 in. per ft; 4 in. and larger at 1/8 in. per ft, unless the code specifies otherwise.

A building drain is the lowest pipe receiving soil and waste inside the building; it becomes the building sewer when it exits the foundation.

A trap arm length is limited by pipe size: 1-1/4 in. trap arm 5 ft, 1-1/2 in. 6 ft, 2 in. 8 ft, 3 in. 12 ft, 4 in. 16 ft, measured to the vent.

Each trap requires a vent; a vent must rise vertically at least 6 in. above the fixture's flood-level rim before offsetting horizontally.

A wet vent may serve only fixtures on the same floor and must be sized per the vent table; a dry vent is a vent that carries no waste.

A cleanout is required at the base of a stack, at the building drain, at changes of direction greater than 45 degrees, and at intervals not exceeding 100 ft in horizontal runs.

A backwater valve is required where a fixture is below the level of the public sewer or where the sewer can back up into the building.

Vent stack and stack vent sizing depends on the total fixture units and the developed length; an undersized vent causes slow drainage and gurgling.

Before soldering or brazing, purge the line and remove all combustible material; a fire watch and a fire extinguisher are required where open flame is used.

Confined space entry requires atmospheric testing (oxygen, combustible gas, hydrogen sulfide) and a permit; never enter a sewer or vault without testing and a standby person.

Backflow and cross-connection control protect the potable supply; a hose bibb without a vacuum breaker is a common cross-connection hazard.

Personal protective equipment for plumbing work includes safety glasses, gloves, hearing protection when using a hammer drill, and knee pads for prolonged kneeling.

Common hand tools: pipe wrench (stillson), basin wrench for tight spaces under sinks, tubing cutter, deburring tool, and a spud wrench for fixture work.

A pressure gauge, a manometer, and a leak-detection method (soap solution or electronic detector) are used to test gas and water lines.

A gas leak is detected with a soap-and-water solution or an electronic detector, never with an open flame; shut off the gas before repairs.

Hot work near wood framing requires a heat shield and a minimum clearance from combustibles; a water heater flue must maintain clearance from combustibles per the listing.