Chapter 7 Excreta Drainage System

Drainage Fixture Unit

What is the meaning of “DFU”

152 mm

No galvanized wrought iron or galvanized steel pipe shall be used underground and shall be kept at least __ above ground.

4 water closets

only ______ or 6 fixture unit traps on any vertical pipe or stack

3 water closets

6 fixture unit traps on any horizontal branch or drain, Not to exceed

4 Fixture Unit

Maximum trap loading (FU) for 51mm

0.3 meter

No vitrified clay pipes or fittings for building drain or sewer shall be used above ground or whenever piping is pressurized by a pump or ejector. They shall be kept at least __ below finish ground level.

31mm

Minimum trap diameter of Drinking Fountain

6 DFU

Minimum DFU of Water closet, public installation.

1 DFU

Minimum DFU of Wash basin (lavatory)

8 Fixture Unit

Maximum trap loading (FU) for 102mm

2 DFU

Minimum DFU of Bidet

0.063 Lps

1 gpm=____ Liters per second

Double sanitary tees

May be used when the barrel of the fitting is at least 2 pipe sizes larger than the largest inlet.

6 Fixture Unit

Maximum trap loading (FU) for 76mm

32mm

Minimum trap diameter of Wash basin (lavatory)

15 metes, 15 meters

Each horizontal drainage pipe shall be provided with a cleanout at its upper terminal and each run of piping which is more than ____ in total developed length shall be provided with a cleanout and at every ____ length or a fraction thereof.

38mm

Minimum trap diameter of Bidet

38mm

What is the size of the clean out if the size of the pipe is 38mm?

1.5 meters

Cleanouts may be omitted on a horizontal drain line less than ____ in length unless such line is serving sinks or urinals.

135 degrees

An additional cleanout shall be provided on a horizontal line with an aggregate offset angle of direction exceeding -

0.45 meter vertical, 0.75 meter horizontal

Cleanouts in underfloor piping shall be extended to or above the finished floor or shall be extended outside the building when there is less than ____ and ____ clearance from the means of access to such cleanout.

305 mm

Each cleanout in piping 51 mm or less in size shall be installed so that there is a clearance of not less than __ in front of the cleanout.

Countersunk cleanout plugs

type of plug that shall be installed where raised heads may cause hazard to passing personnel or vehicles.

51mm or 2 inches

Minimum trap diameter of Urinal, wall mounted, integral trap, trap arm only.

51mm or 2 inches

Minimum trap diameter of Floor drains

2.4 meter

Fixture outlets shall not be connected to the horizontal excreta drainage piping system within ____ of any vertical to horizontal change of direction of a stack containing suds-producing fixtures.

4 DFU

Minimum DFU of Water closet, private installation.

Gravity

Where practicable, all plumbing fixtures shall be drained into the public sewer or private sewage disposal system by _____

backwater valve

Drainage piping serving fixtures which have flood level rims located below the elevation of the nearby upstream manhole invert of the public sewer serving such drainage piping shall be protected from backflow of sewage by installing an -

2 DFU

Minimum DFU of Floor drain

76mm or 3 inches

Minimum trap diameter of Water closet, public installation.

ejector pump

The sewage or other liquid wastes shall then be lifted and discharged into the building drain or building sewer by an approved.

50.8mm or 2”

The minimum size of any pump discharge or any discharge pipe from a sump having a water closet connected thereto shall not be less than ____ diameter.

Gate valve

Shall be located at the discharge side of the backwater or check valve.

51 mm

The invert of the lowest inlet to the tank shall have a minimum distance of ___ above the high water or "starting" level of the pumping operation.

89mm

What is the size of the clean out if the size of the pipe is 102mm?

32 mm

The diameter of an individual vent shall not be less than ____ nor less in size than 1-1/2 the diameter of the drain to which it is connected.

innocuous

sewage deleterious to surface or subsurface water shall not be discharged into ground unless rendered

22.5°, 45°, 60° bends

changes in direction of drainage piping shall be of angles presented by a

ABS and PVC DWV (Drain, Waste, Vent)

shall be used in high-rise building with discretion of the Master Plumber or Designer and with full consent to the owner

recessed drainage

fittings on screwed pipe joints shall be of the ______ type

2%

threads of drainage fittings shall be tapped to allow ___ grade

6 fixture units each

clothes washers in groups of 3 or more shall be rated at ____ for the common horizontal and vertical waste pipe sizing

6

WC shall be computed as _ fixture units when determining septic tank size

0.063 L/s

for continuous flow such as from a sump pump or ejector, air conditioning equipment, 2 fixture units shall be allowed for every _____ of flow

double sanitary tee
or
double wye and 1/8 bend

two fixtures set back to back or side to side, may be served by a single vertical drainage via _____

0.8

multiplier factor for horizontal fixture units for 1% slope

sump or receiving tank

needed protection for fixtures located below the crown level of the main sewer

accessible backwater or wing check valve and gate-valve

needed for vertical discharge line from ejector to a horizontal drainline

dual pumps or ejectors

sumps and receiving tanks for public use shall be provided with ______

bolt and gasket type manhole

cover of sump and receiving tank

3kg of each meter

minimum air pressure for air tank for the height the sewage is raised

cast iron or brass

each cleanout fitting for cast iron soil pipe shall consist of a ____ or _____ body with an approved screwed brass plug

72°

cleanouts may be omitted on short horizontal drainage pipe installed at a slope of ___ or less from the vertical line

upper terminal cleanout

two-way cleanout inside the building wall near the connection between the building drain and building sewer or installed outside of a building at the lower end of the building drain and extended to grade, may be substituted for an _______

90° cleanout

each ______ extension shall be extended from a wye type fitting

51mm or less

cleanout size that needs clearance of 305 mm in front of the cleanout

larger than 51mm

cleanout size that needs clearance of 450mm in front of the cleanout

6.1m

maximum distance of underfloor cleanout from an access door, trap door or crawl hole

508mm

minimum diameter of a manhole of a sewer line

• Must have a separate, independent system.

• Each building needs its own sewer connection.

• Front building drain can serve rear building if sized properly.

3 drainage rules for new building

61 meters

if the public sewer is more than _____ away from the building, the public sewer is considered as not being available

• No rain, surface, or subsurface water

• No cesspool, septic tank effluent, seepage pit, or underdrain

• No commercial food waste grinder

What must not be connected to excreta drainage systems?

2% or 21mm/m

recommended slope of building sewer

0.5% or 5.3 mm/m

allowable slope for 203mm and larger diameter pipe

1% or 10.5mm/m

allowable slope for 102 and 152.4 mm diamter pipe

0.6m

distance of building sewer from the outer face of any building foundation or wall

0.3m

depth of building sewer below finish surface of ground

7.6m to 15.2m

minimum horizontal distance required from building sewer to water supply wells

15.2m

minimum horizontal distance required from building sewer to streams

0.3m

minimum horizontal distance required from building sewer to public water main (according to this chapter and table 12-1)

3m

minimum horizontal distance required from building sewer to public water main (according to appendix b)

3m

distance of water pipe joints away from sewer line

• The building sewer (or branch) is 3 meters (10 feet) or less in length,

• It is a short, straight-line extension from the building drain, and

• The building drain already has a cleanout.

A cleanout is not required at the connection point if

grade

all required building sewer cleanouts shall be extended to ____

91 m

maximum distance between manholes

0.3m

minimum distance of flexible compression joints outside of the manhole, as connections for inlet and outlet pipe