NM Journeyman Plumber flashcards

33 cards. Read the term and the definition here. The deck at the top of this page is optional.

Fixture unit

A weighted value assigned to a fixture representing its probable drainage or supply demand; one drainage fixture unit equals 1 cubic foot per minute, or 7.5 gallons per minute, of flow.

Air gap

The unobstructed vertical distance through free atmosphere between a waste pipe outlet and the flood-level rim of the receiving fixture; it is the most reliable backflow prevention method.

Trap seal depth

The vertical distance between the crown weir of a trap and the top of the trap dip; the code requires a seal of at least 2 inches and not more than 4 inches.

Trap arm length limit

The maximum horizontal distance from a trap to its vent, determined by trap size: 5 feet for 1-1/4 inch, 6 feet for 1-1/2 inch, 8 feet for 2 inch, and 12 feet for 3 inch.

Vent stack termination

A vent must extend at least 6 inches above the roof, or 12 inches where snow may accumulate, and must be at least 3 feet from windows, doors, and air intakes.

Grease interceptor

A receptacle installed on the waste line of a commercial kitchen to intercept fats, oils, and grease before they enter the sewer; it must be sized to the fixture load and be accessible for cleaning.

Storm drain sizing

Roof drain flow in gallons per minute equals roof area in square feet times the design rainfall rate in inches per hour times 0.0104.

Subsoil drain

A perforated pipe installed around foundations or under basements to collect groundwater; it must discharge to a storm drain, sump, or dry well and may not connect to the sanitary sewer.

Temperature and pressure relief valve

A listed safety valve required on every water heater, set to open at 210 degrees Fahrenheit and 150 psi; its discharge pipe must be full size and must not be valved off or trapped.

Thermal expansion tank

A tank installed on the domestic water supply downstream of a check valve or backflow preventer to absorb the pressure increase caused by heating water in a closed system.

Sediment trap

A fitting installed on a gas appliance connector with a leg extending downward at least 3 inches below the gas inlet to collect dirt and scale before it reaches the appliance controls.

Gas piping test pressure

Gas piping must be tested at 1-1/2 times the working pressure, but not less than 3 psi, for at least 10 minutes using air or an inert gas.

Combustion air requirement

A confined space requires 50 cubic feet of volume per 1,000 Btu per hour of appliance input, or two permanent openings sized at 1 square inch per 1,000 Btu per hour.

Carbon monoxide alarm

A listed alarm required in the vicinity of bedrooms and on each floor of a dwelling that contains a fuel-burning appliance, to warn of incomplete combustion products.

New Mexico plumbing authority

The Construction Industries Division of the Regulation and Licensing Department administers the state plumbing code, which is based on the Uniform Plumbing Code with state amendments.

Rough-in inspection

An inspection performed after the piping is installed and tested but before it is covered by walls, floors, or ceilings; approval is required before covering the work.

Water supply test

A test of the water distribution system at 100 psi for at least 15 minutes, or at working pressure for 30 minutes, whichever is greater, before the piping is covered.

Drainage system test

A test of the drainage and vent system with water or air; a water test requires filling the system to the highest point and holding for at least 15 minutes.

Journeyman plumber license

A state credential issued after passing the journeyman examination and completing the required hours of supervised plumbing experience; it must be renewed periodically.

Backflow prevention assembly testing

A test performed by a certified tester, usually annually, to verify that a backflow preventer operates correctly; the report is filed with the water purveyor and the authority having jurisdiction.

Static pressure loss by elevation

Water pressure changes 0.433 psi per foot of elevation; a 30-foot rise reduces static pressure by about 13 psi.

Pipe volume formula

The volume in gallons of a pipe equals 0.0408 times the inside diameter in inches squared times the length in feet; a 1-inch pipe holds about 0.041 gallons per foot.

Slope conversion

A slope of 1/4 inch per foot equals 2.08 percent; percent slope equals rise divided by run times 100, and fall equals slope times run.

Flushometer residual pressure

A minimum of 8 psi flowing pressure is required at a flushometer valve, and 8 psi is required at the highest fixture served by the water distribution system.

Pressure-reducing valve

A device required where static water pressure exceeds 80 psi; it reduces pressure to a safe level and requires a thermal expansion tank or relief valve downstream.

Water closet clearance

A water closet must have at least 15 inches from its centerline to a side wall and at least 21 inches of clear space in front of the bowl.

Shower valve requirement

Shower and tub-shower valves must be pressure-balancing or thermostatic mixing type to limit scald, and public lavatory fittings must be temperature-limiting.

Cleanout location

Cleanouts are required at the base of each soil stack, at the building drain and sewer junction, at changes of direction greater than 45 degrees, and at intervals not exceeding 100 feet.

Building drain size

A building drain must be at least 2 inches in diameter and at least 3 inches where it serves a water closet; a building sewer must be at least 3 inches.

Water heater drain pan

A pan at least 1-1/2 inches deep is required under a water heater where leakage could cause damage; the pan must drain to an approved location.

Garage water heater elevation

A water heater installed in a garage must be raised at least 18 inches above the floor where the ignition source is within 18 inches of the floor, to prevent ignition of gasoline vapors.

Vent connector draft hood

A draft hood or draft diverter must be installed on an appliance that is not direct-vent, and it must not be modified; a blocked flue must be detected by a spill switch or carbon monoxide alarm.

Plumbing permit exemption

A permit is not required for minor repairs such as replacing a faucet or a washer, but replacement of a water heater or installation of new piping requires a permit.