OR Plumber flashcards
OR Plumber · Build recall with a focused review session.
32 cards. Read the term and the definition here. The deck at the top of this page is optional.
- Water column pressure
- One psi equals 2.31 feet of water head. This conversion lets a plumber convert static pressure to the height of water it can support in a system.
- Fixture unit
- A unitless measure of the probable drainage load a fixture imposes on a drainage system, roughly equivalent to one gallon per minute of flow.
- Drainage pipe slope
- Horizontal drainage pipe 3 inches and smaller must slope at least 1/4 inch per foot. Pipe 4 inches and larger may slope 1/8 inch per foot.
- Type L copper
- Standard-weight copper tube commonly used for above-ground water distribution. Type K is heavier and used underground; Type M is lighter and limited.
- Trap seal depth
- The water depth in a fixture trap must be at least 2 inches and no more than 4 inches to prevent sewer gas while allowing flow.
- Air gap backflow protection
- An unobstructed vertical distance between the water outlet and the flood level rim of the receiving fixture, providing the highest level of backflow protection.
- Lavatory drain size
- A lavatory requires a minimum 1-1/4 inch drain. A bathtub requires 1-1/2 inch, and a water closet requires 3 inch.
- Pressure-balancing shower valve
- A shower valve that maintains a stable outlet temperature by adjusting hot and cold flow when supply pressure changes, reducing scalding risk.
- Minimum fixture pressure
- Flush-tank water closets need about 8 psi static pressure at the fixture; flushometer valves typically need 15 psi or more.
- Pressure-reducing valve
- A device installed on a water service when static pressure exceeds 80 psi, reducing downstream pressure to a safe level for fixtures and piping.
- RPZ assembly
- A reduced-pressure-zone backflow preventer used for high-hazard cross-connections such as irrigation and boiler feed, providing the highest protection level.
- Maximum water velocity
- Cold water piping should not exceed about 8 feet per second and hot water about 5 feet per second to limit noise, erosion, and pressure loss.
- Building drain
- The lowest pipe of a drainage system that receives soil and waste inside the building, extending to the building sewer at or outside the foundation.
- Wet vent
- A vent that also serves as a drain for fixtures on the same floor, sized per code and connected to a dry vent above the highest fixture.
- Trap arm length
- The distance from a fixture trap weir to its vent connection, limited by code, commonly 5 feet for 1-1/4 inch and 6 feet for 1-1/2 inch traps.
- Backwater valve
- A device installed on a drainage line to prevent sewage from flowing backward into a building when the public sewer surcharges or floods.
- Vent terminal height
- A vent stack must extend at least 6 inches above the roof surface and be located at least 10 feet from operable windows or air intakes.
- Cleanout spacing
- Horizontal drainage lines require cleanouts at intervals not exceeding 100 feet and at each change of direction greater than 45 degrees.
- Oregon Plumbing Specialty Code
- The Oregon code governing plumbing installation, based on the Uniform Plumbing Code and administered by the Oregon Building Codes Division.
- Plumber licensing
- Oregon requires individual plumber licenses (apprentice, journeyman, master) and a separate plumbing contractor license for business operation.
- Plumbing permit
- Authorization from the local jurisdiction or state required before starting most plumbing work, including fixture replacement and water heater installation.
- Concealed work inspection
- An inspection that must be requested and passed before plumbing is covered by walls, floors, or ceilings, allowing verification of installation.
- T&P relief discharge
- The temperature-and-pressure relief valve on a water heater must discharge to within 6 inches of the floor or to a safe, visible location.
- Water heater seismic strapping
- Oregon requires water heaters to be secured with two straps, one in the upper third and one in the lower third, plus base anchoring.
- Backflow tester certification
- Oregon requires backflow assembly testers to hold current certification, and certain assemblies must be tested annually by a certified tester.
- Building sewer definition
- The pipe that carries sewage from the building drain to the public sewer or private disposal system, beginning outside the building foundation.
- Flushometer valve pressure
- A flushometer valve typically requires at least 15 psi flowing pressure at the fixture to operate correctly and reset the diaphragm.
- Expansion tank
- A closed tank installed on a water heating system to absorb the volume increase from thermal expansion and protect piping and relief valves.
- 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.
- Trap primer
- A device that automatically adds water to a floor drain trap to maintain the trap seal and prevent sewer gas from entering the building.
- Developed length
- The total equivalent pipe length including straight run plus fitting allowances, used to size water supply piping for allowable pressure loss.
- Stack vent
- The extension of a soil or waste stack above the highest fixture branch, serving as a vent to the outdoors.