Glossary

appliance

piece of equipment which may require connection to a plumbing system

back pressure

pressure higher than the supply pressure

back-siphonage

backflow caused by a negative pressure in the supply system

back-siphonage preventer

device or a method that prevents back-siphonage

backflow

flowing back or reversal of the normal direction of the flow

backflow preventer

device or method that prevents backflow

backwater valve

check valve designed for use in a gravity drainage system

branch

soil-or-waste pipe connected at its upstream end to the junction of two or more soil-or-waste pipes or to a soil-or-waste stack, and connected at its downstream end to another branch, a sump, a soil-or-waste stack or a building drain

branch vent

vent pipe that is connected at its lower end to the junction of two or more vent pipes and is connected at its upper end either to a stack vent, vent stack or header, or is terminated in open air

building

any structure used or intended for supporting or sheltering any use or occupancy

building drain

main trunk that other parts of the system connect to

building sewer

pipe that is connected to a building drain 1 m outside a wall of a building and that leads to a public sewer or private sewage disposal system

building trap

trap that is installed in a building drain or building sewer to prevent circulation of air between a drainage system and a public sewer

check valve

valve that permits flow in only one direction

cleanout

access provided in drainage and venting systems to provide for cleaning and inspection services

clear-water waste

waste water with impurity levels that will not be harmful to health and may include cooling water and condensate drainage from refrigeration and air conditioning equipment and cooled condensate from steam heating systems, but does not include storm water

combined building drain

building drain that is intended to conduct sewage and storm water

combined building sewer

building sewer that is intended to conduct sewage and storm water

continuous vent

vent pipe that serves two or more fixtures and is an extension of a wet vent

critical level

level of submergence at which the back-siphonage preventer ceases to prevent back-siphonage

developed length

length along the centre line of the pipe and fitting

directly connected

physically connected in such a way that water or gas cannot escape from the connection

drainage system

assembly of pipes, fittings, fixtures, traps and appurtenances that is used to convey sewage, clear-water waste or storm water to a public sewer or a private sewage disposal system, but does not include subsoil drainage pipes

dual vent

vent pipe that serves two fixtures at the junction of the trap arms

dwelling unit

suite operated as a housekeeping unit used or intended to be used as a domicile by one or more persons and usually containing cooking, eating, living, sleeping and sanitary facilities

fire separation

construction assembly that acts as a barrier against the spread of fire

fixture

receptacle, appliance, apparatus or other device that discharges sewage or clear-water waste, includes a floor drain

fixture drain

pipe that connects a trap serving a fixture to another part of a drainage system

fixture outlet pipe

pipe that connects the waste opening of a fixture to the trap serving the fixture

fixture unit - drainage systems

unit of measure based on the rate of discharge, time of operation and frequency of use of a fixture that expresses the hydraulic load that is imposed by that fixture on the drainage system

fixture unit – water distribution systems

unit of measure based on the rate of supply, time of operation and frequency of use of a fixture or outlet that expresses the hydraulic load that is imposed by that fixture or outlet on the water supply system

flood level rim

top edge at which water can overflow from a fixture or device

flow control roof drain

roof drain that restricts the flow of storm water into the storm drainage system

fresh air inlet

vent pipe that is installed in conjunction with a building trap and terminates outdoors

header

vent pipe that connects two or more vent stacks or stack vents to outdoors

indirectly connected

not directly connected

individual vent

vent pipe that serves one fixture

interceptor

receptacle that is installed to prevent oil, grease, sand or other materials from passing into a drainage system

leader

pipe that is installed to carry storm water from a roof to a storm building drain or sewer or other place of disposal

nominally horizontal

angle of less than 45 degrees with the horizontal

nominally vertical

angle of not more than 45 degrees with the vertical

occupancy

use or intended use of a building or part thereof for the shelter or support of persons, animals or property

offset

piping that connects the ends of two pipes that are parallel

owner

any person, firm or corporation controlling the property under consideration

plumbing contractor

a person, corporation or firm that undertakes to construct, extend, alter, renew or repair any part of a plumbing system

plumbing system

drainage system, a venting system and a water system or parts thereof

potable

safe for human consumption

private sewage disposal system

privately owned plant for the treatment and disposal of sewage (such as a septic tank with an absorption field)

private water supply system

assembly of pipes, fittings, valves, equipment and appurtenances that supplies water from a private source to a water distribution system

relief vent

auxiliary vent which provides additional circulation of air between drainage systems and venting systems

riser

water distribution pipe that extends through at least one full storey

roof drain

fitting or device that is installed in the roof to permit storm water to discharge into a leader

roof gutter

exterior channel installed at the base of a sloped roof to convey storm water

sanitary building drain

building drain that conducts sewage

sanitary building sewer

building sewer that conducts sewage

sanitary drainage system

drainage system that conducts sewage

sanitary sewer

sewer that conducts sewage

service water heater

device for heating water for plumbing services

sewage

any liquid water other than clear-water waste or storm water

soil-or-waste pipe

pipe in a sanitary drainage system

soil-or-waste stack

a vertical soil-or-waste pipe that passes through one or more storeys, and includes any offset that is part of the stack

stack vent

vent pipe that connects the top of a soil-or-waste stack to a header or to open air

storey - plumbing

interval between two successive floor levels

storm building drain

building drain that conveys storm water

storm building sewer

building sewer that conveys storm water

storm drainage system

drainage system that conveys storm water

storm sewer

sewer that conveys storm water

storm water

water that is discharged from a surface as a result of rainfall or snowfall

subdrainage system

drainage system that does not drain by gravity to the building sewer

subsoil drainage pipe

pipe that is installed underground to intercept and convey subsurface water

suite

single room or series of rooms of complementary use, operated under a single tenancy and includes dwelling units, individual guest rooms in motels, hotels, boarding houses, rooming houses and dormitories as well as individual stores and individual or complementary rooms for business and personal services occupancies

trap

fitting or device that is designed to hold a liquid seal that will prevent the passage of gas but will not materially affect the flow of a liquid

trap arm

that portion of a fixture drain between the trap weir and the vent pipe fitting

trap standard

trap for a fixture that is integral with the support for the fixture

vent pipe

pipe that is part of a venting system

vent stack

vent pipe that is connected at its upper end to a header or is terminated in open air and that is used to limit pressure differential in a soil-or-waste stack

venting system

assembly of pipes and fittings that connects a drainage system with outside air for circulation of air and the protection of trap seals in the drainage system

water distribution system

assembly of pipes, fittings, valves and appurtenances that conveys water from the water service pipe or private water supply system to water supply outlets, fixtures, appliances and devices

water service pipe

pipe that conveys water from a public water main or private water source to the inside of a building

water system

private water supply system, a water service pipe, a water distribution system or parts thereof

wet vent

soil-or-waste pipe that also serves as a vent pipe

Abbreviations