This is the lowest horizontal drainage piping inside a building.
What is the building drain?
This water-filled fitting prevents sewer gas from entering an occupied space
What is a trap?
Unlike a pressure tee, this fitting has a curved inlet that directs drainage flow downward.
What is a sanitary tee or tee-wye?
Horizontal drainage piping depends on this force to move wastewater.
What is gravity?
This piping system allows air movement and protects fixture trap seals
What is the venting system?
This pipe begins outside the building and conveys sewage to a public sewer or private sewage-disposal system.
What is the building sewer?
This type of trap is preferable where a removable connection could loosen and cause concealed water damage.
What is a solid trap?
This fitting is normally used to make a smooth branch connection into horizontal drainage piping.
What is a wye?
This layer provides continuous support beneath drainage piping installed in a trench.
What is bedding?
Fixture discharge creates this type of pressure ahead of the moving wastewater
What is positive pressure?
This section of piping extends from a fixture’s trap to the connection with its vent.
What is the trap arm?
This fitting provides access for inspecting and mechanically cleaning drainage piping
What is a cleanout?
A sanitary tee must not be installed in either of these two positions for horizontal drainage flow.
What are on its back or on its side?
Pipe markings should face in this direction when piping is installed in a trench so inspectors can see them
What is upward?
Fixture discharge can create this type of pressure behind the moving wastewater.
What is negative pressure?
This pipe connects the fixture outlet directly to the trap.
What is the fixture outlet pipe?
The maximum total fall of a trap arm is related to this measurement of the pipe
What is the pipe diameter?
Back-to-back water closets require careful fitting selection to prevent this unwanted movement of discharge from one fixture toward the other.
What is crossflow?
This device protects low-level fixtures when sewage reverses direction because a public sewer is surcharged
What is a backwater valve?
This vent serves one fixture and connects near the fixture’s trap arm
What is an individual vent?
This vertical soil-or-waste pipe passes through one or more storeys and carries fixture discharge.
What is a soil-or-waste stack?
This condition occurs when pressure removes water from a trap, allowing sewer gas to enter the building.
What is loss of the trap seal, or siphonage?
Drainage fittings are shaped to preserve this while reducing turbulence and solid accumulation.
What is the direction and smooth movement of flow?
Piping passing through a foundation opening must be protected from structural loading and allowed this accommodation.
What is movement or settlement allowance?
This vent carries both wastewater and air while protecting downstream fixture traps.
What is a wet vent?