topic 6: sanitary drainage system Flashcards
What are the 2 general rules in designing the sanitary system?
- the pipes should take the shortest possible route to the house sewer
- control components should be located strategically so as to ensure efficient circulation
control components such as ___, ___, and ____.
- clean-outs
- traps
- vents
What are the 2 subsystems of the sanitary system?
- waste collection system
- ventilation system
What are the 7 essential parts of the sanitary drainage system?
- waste pipe
- vent pipe
- branch
- stack
- trap
- house/building drain
- house/building sewer
_____ conveys only wastewater or liquid waste free of fecal matter.
waste pipe
____ is used for ensuring the circulation of air in a plumbing systems and for relieving the negative pressure exerted on a trap seals.
vent pipe
____ is any part of the piping system other than a main, riser or stack.
branch
____ is the vertical main of a system of soil, waste or vent piping extending through one or more stories and extended through the roof.
stack
____ is a fitting or device designed and constructed to provide, when properly vented, a liquid seal which prevents the backflor of foul air or methane gas without materially affecting the flow of sewage or wastewater through it.
trap
____ “trap” water and stop sewer gas.
trap
____ allows pipes to drain without “gulping” air through traps.
air vents
_____ is part of the lowest horizontal piping of a plumbing systems which receives the discharges from the soil, waste and other drainage pipes inside of a building and conveys it to the house sewer outside of the building.
house/building drain
house/building sewer extends from the house drain at a point _____ meters from the outside face of the foundation wall of a building to the junction with the street sewer to any point of discharge, and conveying the drainsge of one building site.
0.60
What are the 3 principles of waste and soil (excreta) pipes rough-in?
- horizontal to horizontal change in direction
- vertical to horizontal change in direction
- horizontal to vertical change in direction
_____ use 45° wye branches, combination wye - 1/8 bend branches, or other approved fittings of equivalent sweep.
horizontal to horizontal change in direction
_____ 45° wye branches or other approved fittings of equivalent sweep.
vertical to horizontal change in direction
____ use 45° or 60° wye branches, combination wye - 1/8 bend branches, sanitary tee or sanitary tapped tee branches, or other approved fittings of equivalent sweeps.
horizontal to vertical change in direction
____ no fittins having more than one inlet at the same level shall be used (i.e., sanitary cross).
horizontal to vertical change in direction
_____ may be used when the barrel of the fitting is at least two pipe (2) sizes larger than the largest inlet, (pipe size recognized for this purpose are 51, 64, 76, 89, 102, 114, 127, & 152 mm dia.)
double sanitary tees
The size of waste pipes or soil pipes depends on the _____.
amount of waste it carries
A _____ discharges 0.47 liters/sec or 28.3 liters/min (7.5 gallons per min or 1 cu ft per min), which is equivalent to the Fixture Unit (F.U.)
lavatory
A fixture unit is equal to _____ of water drained in an 11/4 pipe over one minute.
1 cubic foot
Capacity over _____ shall be determined by the Administrative Authority.
3.15 L/s
Minimum slope or pitch of horizontal drainage pipe - ______ (1/4” per foot).
2% or 20mm/m
What are the 6 types of permissible traps?
- common P-trap
- deep seal trap
- stand trap
- bottle trap
- running trap
- drum trap
____ is used for lavatories, kitchen sinks, laundry tubs, & urinals.
common P-trap
What are the 4 materials commonly used for the P-trap?
- nickel
- chrome plated brass
- galvanized malleable copper
- PVC
The seal of common P-trap is ____.
50 mm
_____ water seal is about twice the size of the common P-trap.
deep seal P-trap
_____ is used for extreme conditions because resealing equality is greater.
deep seal P-trap
The seal for deep seal P-trap is _____.
7.5 cm
____ is used for fixtures like slop sinks that are usually built low in the ground, leaving very little space for a foundation & a trap.
stand trap
_____ serves as water seal & structural support for the fixture.
stand trap
____ is perfect for small spaces under sinks that are cramped because of its shape.
bottle trap
____ go straight up and down horizontal which maximizes space and makes it easy to maintain.
bottle trap
____ is used within the line of house drain.
running trap
Drum trap has a large diameter (around _____).
0.16 m
____ is used for fixtures that discharge large amount of water (bathtubs, shower or floor drains).
drum trap
What are 3 types of prohibited traps?
- traps with movable parts or concealed interior partitions
- no fixtures shall be double-trapped
- S-trap
_____ are predecessor of P-traps.
S-trap
____ is used before traps has to connect to a ventilation line.
S-trap
What are the 3 requirements of traps?
- each plumbing fixture, except those with integral traps, shall be separately trapped with an approved-type water-sealed trap.
- only one trap shall be permitted on a trap arm
- one trap, centrally located, may serve three single compartment sinks or laundry tubs or lavatories, adjacent to each other and in the same room.
One trap, centrally located, may serve three single compartment sinks or laundry tubs or lavatories, adjacent to each other and in the same room, where their waste outlets are not more than _____ apart.
0.75 m
The trap shall be _____ size as the trap arm to which it is connected.
the same
Each fixture trap shall have a trap seal of water of not less than _____ and not more than ____ (except where a deeper seal is found necessary by the Administrative Authority for special conditions).
51 mm, 102 mm
In the installation of traps, the vertical distance between a fixture outlet tailpiece and the trap weir shall not exceed _____ in length.
0.60
The developed length of the trap arm (measured from the top of closet ring to inner edge of vent) of a water closet or similar fixture shall not exceed _____.
1.8 m
For trap arm 76 mm dia. or larger, a cleanout is required for a change of direction of greater than _____ deg.
22 1/2
In no case shall the trap distance be less than _____ times the diameter of the trap arm.
2
____ is a device designed and installed to separate and retain deleterious, hazardous or undesirable matters from normal wastes and permits normal sewage or liquid wastes to discharge into the disposal terminal by gravity.
interceptors
Interceptors shall have a water seal of not lesss than ____ deep.
152 mm
What are the 4 types of interceptors?
- grease interceptors
- sand interceptors
- solids interceptors
- oil interceptor
____ interceptors are limited to lavatories and sinks and must comply with the requirements of section 5.3.7.
drum trap solids interceptors
What are the 5 requirements of clean-outs (required)?
- at the upper terminal of every horizontal sewer or waste line
- at each run of piping more than 15 meters (50 feet) in total developed length
- at every 15 m (50 ft) of total developed length or a fraction thereof
- additional clean-out shall be provided on a horizontal line with an aggregate offset angle exceeding 135°
- inside the building near the connection between the building drain and the building sewer or installed outside the building at the lower end of the building drain and extended to grade.
What are the 2 requirements of clean-outs (not required)?
- on a horizontal drain less than 1.5 m in length unless such line is servinng sinks or urinals
- on short horizontal drainage pipe installed at a slope of 72 deg or less from the veritcal lin (or at an angle of 1/5 bend)
What are 6 examples of house drain appliances?
- grease traps
- house traps
- drain tiles
- garage traps
- backflow valves
- sewage ejectors
_____ is used for fixtures where grease may be introduced into the drainage or sewer system in quantities that can effect line stoppage or hinder sewage tratment or private sewage disposal.
grease traps
____ is used for establishments like restaurants, cafes, lunch counters, cafeterias, bars and clubs, hoteal hospital, sanitarium, factory or school kitchens.
grease traps
No grease trap shall be installed for a facilitity that has an approved rate of flow of more than _____ (54.26 gpm) nor less than _____ (20.74 gpm).
3.4 Liters, 1.3 L/s
Each grease trap shall have an approved water seal of not less than ____ in depth or the diameter of its outlet, whichever is greater.
51 mm
What are the 2 main types of grease trap?
- earth cooled grease trap
- mechanical grease trap
_____ is placed in the house drain immediately inside the foundation wall of the building.
house traps
Vents in house traps are minimum ____ the diameter of the building drain.
1/2
____ is used to prevent groundwater from seeping through the basement walls & foundation.
drain tiles
_____ areplaced around the perimeter of the foundation where water is collected.
hollow tiles
____ are connected to the house draim and sump pit.
drain tiles
____ a.k.a. garage catcch basin.
garage traps
Operating principles: trap is filled with water & located at the lowest point of the garage so it can collect all wastes.
garage traps
Operating principles (separation of grease from water): grease suspended in waste floats to the surface
grease traps
____ is used in house drain to prevent the unliekly occurrence of backflows.
back flow valves
____ works similar to check valves.
back flow valves
____ pumps the wastes up from the sump pit to the sewers (which are usually higher than basement levels).
sewage ejectors
