PLUMBING TERMINOLOGY

ACID VENT

a pipe venting an acid waste system.

ACID WASTE

a pipe, which conveys liquid waste matter containing a pH of 6.9 or less.

ACTIVE SLUDGE

sewage sediment, rich in destructive bacteria that can be used to break down fresh sewage quickly

AEROBIC

bacteria living or active only in the presence of free oxygen.

AIRBREAK

a piping arrangement in which a drain from a fixture, appliance, or device indirectly discharges into a fixture, receptacle or interceptor at a point below the flood level of the receptacle to prevent backflow or back siphonage.

AIRGAP

the unobstructed vertical distance through the free atmosphere between the lowest opening from any pipe or faucet conveying water or waste to a tank, plumbing fixture receptor or other device and the flood level rim of the receptacle.

AIR TEST

a test that is applied to the plumbing system upon its completion, but before the building is plastered

ANAEROBIC

bacteria living or active in the absence of free oxygen.

AREA DRAIN

a receptacle designed to collect surface or rain water from a determined or calculated open area.

ARTERIAL VENT

a vent serving the building drain, it also vents the public sewer.

BACKFLOW

the flow of water or other liquids, mixtures or substances into the distributing pipes of a potable supply of water from any source or sources other its intended source.

BACK PRESSURE

air pressure in drainage pipes greater than atmospheric pressure.

BACKING RING

a metal strip used to prevent melted metal from the welding process, from entering a pipe when making a but-welded point.

BACKSIPHONAGE

the flowing back of used, contaminated or polluted water from a plumbing fixture or vessel into the potable water supply pipe due to a negative pressure in such pipes.

BACK VENT PIPE

also called as individual vent. The part of the vent system which connect directly with an individual trap underneath or behind the fixtures and extend to the branch or main soil, or waste pipe at any point higher than the fixture or fixture’s trap it serves.

BALL CHECK VALVE

A device used to stop the flow of media in one direction while allowing flow in an opposite direction. The closure member used is spherical or ball-shaped.

BALL COCK

a faucet opened or closed by the fall or rise of a ball floating on the surface of the water.

BALL JOINT

A connection in which a ball is held in a cup-like shell that allows movement in every direction.

BALL VALVE

A spherical- shaped gate valve providing very tight shut-off.

BATTERY OF FIXTURE

Any group of two or more similar adjacent fixtures, which discharge into a common horizontal waste or soil branch.

BELL OR HUB

that portion of the pipe which for a short distance, is sufficiently enlarged to receive the end of another pipe of the same diameter for the purpose of making a joint.

BIBB

Synonymous with faucet, cock tap, plug, etc. The word faucet is preferred.

BIDET

a plumbing fixture used for washing the middle part of the body, especially the genitals.

BLACK PIPE

A steel pipe that has not been galvanized.

BRANCH

Any part of the piping system other than a main, riser, or stack.

BUILDING DRAIN

that part of the lowest piping of a drainage system receives the discharge from the soil, waste and other drainage pipes inside the walls of the building and conveys it to the building sewer, which begins outside the building walls. The building drain shall be considered to extend 90 cm outside the building wall.

BUILDING SEWER

that part of the horizontal piping of a drainage system which extends from the end of the building drain and which receives the discharge of the building drain and conveys it to the public sewer, private sewer, individual sewage disposal system or other point of disposal.

BUILDING TRAP

a device, fitting or assembly of fittings installed in the building drain to prevent the circulation of air between the drainage of the building and the building sewer. It is usually installed as a running trap.

BUSHING

a pipe fitting for connecting a pipe with a female fitting of larger size. It is a hollow plug with internal and external threads.

BUTT WELD JOINT

a welded pipe joint made with the ends of the two pipes butting each other, the weld being around the periphery.

CAP

a fitting into which the end of a pipe is screwed for the purpose of closing the end of the pipe.

CAULKING

the method of rendering a joint tight against water or gas by plugging it with oakum, lead or other materials.

CATCH BASIN

a receptacle in which liquids are retained for a sufficient period to deposit materials.

CESSPOOL

a lined excavation in the ground which receives the discharge of a drainage system or part thereof, so designed as to retain the organic matter and solids discharging therein, but permitting the liquids to seep through the bottom and sides.

CLEANOUT

a plug or cover joined to an opening in a pipe, which can be removed for the purpose of cleaning or examining the interior of the pipe.

CLOSE NIPPLE

a nipple with a length twice the length of a standard pipe threads.

COCK

an original form of valve having a hole in a tapered plug, which is rotated to provide passageway for fluid.

CORPORATION COCK

a stopcock screwed into the street water main to supply the building/house service connection.

COUPLING

a pipe fitting with female threads only used to connect two pipes in a straight line.

CROSS CONNECTION

any physical connection or arrangement between two otherwise separated piping systems, one of which contains potable water and the other water or other substances of unknown or questionable safety, whereby flow may occur from one system to the other, the direction of flow depending on the pressure differential between the two systems.

CROWN

that part of the trap in which the direction of flow is changed from upward to downward.

CURB BOX

a device at the curb that contains a valve that is turned to shut off a supply line, usually of gas or water.

DEAD END

a branch leading from a soil, waste or vent pipe, building drain or building sewer which is terminated at a developed distance of two feet (0.60 m) or more by means of a plug or other closed fitting.

DEVELOPED LENGTH

the length along the centerline of pipe and fittings, both horizontal and vertical.

DEW POINT

the temperature of a gas or liquid at which condensation or evaporation occurs.

DOWN SPOUT

the rain leader from the roof to the building storm drain, combined building sewer or other means of disposal and located outside of the building.

EFFLUENT

sewage, treated or partially treated, flowing out of sewage treatment equipment.

ELBOW

a fitting that makes an angle between adjacent pipes, the angle 90° , unless another angle is specified.

EXPANSION JOINT

a joint whose primary purpose is to absorbed longitudinal thermal expansion in the pipeline due to heat.

FAUCET

a valve on a water pipe by means of which water can be drawn from or held within the pipe. The valve is placed on the end of the pipe.

FEMALE THREAD

internal thread in a pipe fittings, valve, etc., for making screwed connections.

FERRULE

a metallic sleeve, joint to an opening in a pipe into which a plug is screwed that can be removed for the purpose of cleaning or examining the interior of the pipe.

FIRE LINE

a system of pipes and equipment used exclusively to supply water for extinguishing fires

FIXTURE BRANCH

a pipe connecting several fixtures

FIXTURE DRAIN

the drain from the trap of a fixture to the junction of the drain pipe.

FIXTURE UNIT

A quantity in terms of which the load-producing effects on the plumbing systems of different kinds of plumbing fixtures are expressed on some arbitrarily chosen scale. A measure of probable discharge into the drainage system of various types of plumbing fixtures. Laboratory tests have shown that the rate of discharge of an ordinary lavatory with a nominal 1-1/4 inch (31.8 mm) outlet, trap and waste is about 7.5 gal/min (0.5 L/s).

FLANGE

in pipe work, a ring-shaped plate on the end of a pipe at right angles to the end of the pipe and provided with holes for bolts to allow fastening the pipe to a similarly equipped adjoining pipe. The resulting joint is a flanged joint.

FLASHING

a piece of sheet metal fitter under another piece of flat metal or wood over which water is expected to run.

FLOAT VALVE

a valve, which operated by means of a bulb or ball floating on the surface of the liquid within the tank. The rising and falling action operates a lever, which opens and closes the valve.

FLOOD LEVEL RIM

the top edge or rim of a receptacle or fixture from which water can overflow regardless of the location of any overflow piping from the receptacle.

FLUSH VALVE

a device located at the bottom of the tank for the purpose of flushing water closets and similar fixtures.

FOOT VALVE

a check valve installed at the base of a pump suction pipe. The purpose of a foot valve is to maintain pump prime by preventing pumped liquid from draining away from the pump.

GATE VALVE

a valve in which flow of water is cut off by means of a circular disc, fitting against machine-smoothed faces at right angles to the direction of flow. The disc is raised or lowered by means of a threaded stem connected to the handle of the valve. The opening in the valve is usually as large as the full bore of the pipe.

GLOBE VALVE

a valve in which the flow of water is cut off by means of a circular disc that fits against the valve seat. The plane of movement of the disc is parallel to the normal direction of flow of water, which is turned through a tortuous passage to direct the flow normal to the face of the disc.

GOOSE NECK

a return bend of a small-sized pipe one end of which is about 30.48 cm (1 foot long) and the other end is about 7.62 cm. (3 inches long). It is commonly used as faucet for a pantry sink. Also, the lead connection between a service pipe and water main.

GRADE

the slope or fall of a line of pipe in reference to a horizontal plane. In drainage it is usually expressed as the fall in a fraction of a cm or percentage slope per meter length of pipe.

HORIZONTAL BRANCH

a drain pipe extending laterally from a soil or waste stack or building drain with or without vertical sections or branches, which receives the discharge from one or more fixture drains and conducts it to the soil or waste stack or to the building drain.

INDIRECT WASTE PIPE

a pipe that does not connect directly with the drainage system but conveys liquid wastes by discharging into a plumbing fixture, interceptor or receptacle which is directly connected to the drainage system.

INDIVIDUAL VENT

a pipe installed to vent a fixture trap and connects with the vent system above the fixture served or terminates in the open air.

INDUCED SIPHONAGE

Siphonage which reduces the depth of a fixture trap seal due to the discharge of another fixture.

LATERAL

in plumbing, a secondary pipe line. In sewerage, a common sewer to which no other common sewer is tributary. It receives sewage only from building sewers.

LATRINE

a water closet consisting of a continuous trough containing water. The trough extends under two or more adjacent seats prohibited by most health authorities for permanent installation.

LAVATORY

a fixture designed for washing of the hands or face. Sometimes called a wash basin.

LEACHING WELL OR PIT

a pit or receptacle having porous walls which permit the contents to seep into the ground.

LEADER

the water conductor from the roof to the building storm drain, combined with building sewer, or other means of disposal.

LOCAL VENTILATING PIPE

a pipe on the fixture side of the trap through which vapor or foul air is removed from a room or fixture.

LOOP VENT

1. a circuit vent which loops back to connect with a stack vent instead of a vent stack.

2. Any vent connecting a horizontal branch or fixture drain with the stack vent of the originating waste or soil stack

MAIN

the principal artery of the system of continuous piping to which branches may be connected.

MAIN VENT

the principal artery of the venting system to which vent branches may be connected.

MANHOLE

an opening constructed in a sewer or any part of the plumbing system of sufficient size for a man to gain access thereto.

OAKUM

hemp or old hemp rope soaked in oil to make it waterproof.

PRIVY

an outhouse or structure used for the deposition of excrement.

PRIVY VAULT

a pit beneath a privy in which excrement collects.

PUTREFACTION

biological decomposition of organic matter with the production of ill-smelling products and usually takes place when there is a deficiency of oxygen.

RAW SEWAGE

untreated sewage

RECEPTOR

an approved plumbing fixture or device of such material, shape and capacity as to adequately receive the discharge from indirect waste pipe, so constructed and located as to be readily cleaned.

REDUCER

a pipe fitting with inside thread, larger at one end than at the other.

RELIEF VENT

a vent installed so as to permit additional circulation of air between the drainage and the vent system where the drainage system might otherwise be air bound.

RISER

a water supply pipe, which extends vertically one full story or more to convey water to branches or fixtures.

ROOF DRAIN

a drain installed to receive water collecting on the surface of a roof and to discharge it into the leader (downspout).

SEAL

the vertical distance between the dip and the crown weir of a trap. Also, the water in the trap between the dip and the crown weir.

SEPTIC TANK

a watertight receptacle which receives the discharge of a drainage system, or part thereof, and is designed and constructed to separate solids from the liquid, digest organic matter through a period of detention.

SERVICE PIPE

the pipe from the watermain or source of water supply to the building served.

SEWAGE

any liquid waste containing animal or vegetable matter in suspension or solution and may include liquids containing chemicals in solution.

SEWAGE EJECTOR

a mechanical device used to pump or eject sewage.

SIAMESE CONNECTION

an eye connection used on fire lines so that two lines of hose may be connected to a hydrant or to the same nozzle.

SLUDGE

the accumulated suspended solids of sewage deposited in tanks, beds or basins, mixed with water to form a semi-liquid mass.

SOIL PIPE

any pipe which conveys the discharge of water closets, urinals or fixtures having similar functions, with or without the discharge from other fixtures to the building drain or building sewer.

SOIL STACK PIPE

a vertical soil pipe conveying fecal matter and liquid wastes.

SPIGOT

the end of a pipe which fits into a bell.