AK Plumber key terms

A unitless measure of the probable load a plumbing fixture places on the drainage or water supply system, based on its flow rate and typical duration of use rather than a fixed volume.

A value assigned to a fixture expressing its expected rate of wastewater discharge, used to size drainage piping, building drains, and sewers.

A value expressing the probable demand a fixture places on the water distribution system, accounting for flow rate and frequency of use, used to size supply piping.

The total measured length of a pipe run including all horizontal, vertical, and fitting allowances, used with pressure loss data to size water supply piping.

The water pressure present when no water is flowing, measured in pounds per square inch or in feet of head, and used as the starting point for supply sizing calculations.

The pressure remaining at a point in a piping system while water is flowing, reflecting losses from elevation, friction, and fittings.

The drop in pressure caused by water rubbing against pipe walls and passing through fittings, valves, and meters as it moves through a system.

The lowest piping of a drainage system that receives waste from inside the building and conveys it to the building sewer, ending at the building wall or specified point.

The piping that carries sewage from the building drain to a public sewer, private treatment system, or other point of disposal, beginning outside the building foundation.

A vertical pipe that carries toilet and other soil-bearing waste downward through a building to the building drain.

A vertical pipe that carries liquid waste free of fecal matter from fixtures such as sinks and lavatories down to the building drain.

A vertical pipe that extends upward from the drainage system to open air, providing a path for air to enter and sewer gas to escape while protecting trap seals.

The open end of a vent pipe that extends above the roof to admit air and release gases, required to be located at a specified height and distance from openings.

The depth of water held in a trap that blocks sewer gas from entering a building; it must be maintained within a specific depth range to work properly.

A U-shaped fitting that retains a water seal to prevent sewer gas from passing into occupied space while allowing wastewater to flow through.

The sloped pipe section between a fixture trap and the point where it connects to a branch, drain, or stack, subject to length and slope limits.

The pipe connecting one or more individual fixtures to a stack, branch, or drain, sized by the total fixture units it serves.

An accessible fitting with a removable plug or cap that allows a drain or sewer line to be opened for inspection and clearing of blockages.

A one-way device installed in a drainage line that closes automatically to prevent sewage from flowing backward into a building during a sewer surcharge.

A one-way mechanical vent that opens to admit air into a drainage system when pressure drops and closes to keep sewer gas inside the pipe.

A loud banging or knocking in piping caused by a sudden stop in water flow, creating a pressure surge that can damage pipes and fittings.

A device containing a trapped air chamber or piston that absorbs the pressure surge created when a valve closes quickly, protecting the piping system.

A device that lowers incoming water pressure to a safe, stable level for the building distribution system, protecting fixtures and appliances from excess pressure.

Any actual or potential link between a potable water supply and a source of contamination or pollution that could allow backflow into the drinking water.

An assembly or device installed to stop contaminated water from reversing into a potable supply, often required at service connections and specific fixtures.

A physical separation between a potable water outlet and the flood-level rim of a receptacle, providing the highest level of protection against backflow.

A device that admits air into piping when pressure drops, breaking a siphon so contaminated water cannot be drawn back into the potable supply.

A safety device that opens to release excess pressure or temperature from a water heater, preventing tank rupture or explosion.

The increase in water volume as it is heated, which raises pressure in a closed system and must be accommodated by a device or open connection.

A vessel with a compressed air charge that absorbs the added volume of water created by heating, limiting pressure rise in a closed plumbing system.

The air supplied to a fuel-burning appliance for proper burning of gas, required in sufficient volume to prevent incomplete combustion and carbon monoxide production.

A colorless, odorless gas produced by incomplete combustion that can cause illness or death, making proper venting and combustion air essential.

A fitting on a gas appliance that draws dilution air and maintains steady draft, helping exhaust combustion gases safely up the vent.

A procedure using soap solution, pressure gauges, or approved detectors to verify that gas piping joints and connections do not leak before the system is placed in service.

A valve installed on a gas or water line to stop flow for maintenance or emergencies, required to be accessible and clearly identified.

A pump installed in a pit to remove accumulated groundwater or stormwater from a basement or low area and discharge it to an approved point.

A piping system that collects and carries rainwater and surface water away from a building or site, kept separate from sanitary drainage.

A device installed near a quick-closing valve to cushion pressure surges in water piping, similar in purpose to a water hammer arrestor.