topic 6: sanitary drainage system

Question 1

What are the 2 general rules in designing the sanitary system?

Answer 1

1. the pipes should take the shortest possible route to the house sewer
2. control components should be located strategically so as to ensure efficient circulation

Question 2

control components such as ___, ___, and ____.

Answer 2

1. clean-outs
2. traps
3. vents

Question 3

What are the 2 subsystems of the sanitary system?

Answer 3

1. waste collection system
2. ventilation system

Question 4

What are the 7 essential parts of the sanitary drainage system?

Answer 4

1. waste pipe
2. vent pipe
3. branch
4. stack
5. trap
6. house/building drain
7. house/building sewer

Question 5

_____ conveys only wastewater or liquid waste free of fecal matter.

Answer 5

waste pipe

Question 6

____ is used for ensuring the circulation of air in a plumbing systems and for relieving the negative pressure exerted on a trap seals.

Answer 6

vent pipe

Question 7

____ is any part of the piping system other than a main, riser or stack.

Answer 7

branch

Question 8

____ is the vertical main of a system of soil, waste or vent piping extending through one or more stories and extended through the roof.

Answer 8

stack

Question 9

____ 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.

Answer 9

trap

Question 10

____ “trap” water and stop sewer gas.

Answer 10

trap

Question 11

____ allows pipes to drain without “gulping” air through traps.

Answer 11

air vents

Question 12

_____ 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.

Answer 12

house/building drain

Question 13

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.

Answer 13

0.60

Question 14

What are the 3 principles of waste and soil (excreta) pipes rough-in?

Answer 14

1. horizontal to horizontal change in direction
2. vertical to horizontal change in direction
3. horizontal to vertical change in direction

Question 15

_____ use 45° wye branches, combination wye - 1/8 bend branches, or other approved fittings of equivalent sweep.

Answer 15

horizontal to horizontal change in direction

Question 16

_____ 45° wye branches or other approved fittings of equivalent sweep.

Answer 16

vertical to horizontal change in direction

Question 17

____ 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.

Answer 17

horizontal to vertical change in direction

Question 18

____ no fittins having more than one inlet at the same level shall be used (i.e., sanitary cross).

Answer 18

horizontal to vertical change in direction

Question 19

_____ 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.)

Answer 19

double sanitary tees

Question 20

The size of waste pipes or soil pipes depends on the _____.

Answer 20

amount of waste it carries

Question 21

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.)

Answer 21

lavatory

Question 22

A fixture unit is equal to _____ of water drained in an 11/4 pipe over one minute.

Answer 22

1 cubic foot

Question 23

Capacity over _____ shall be determined by the Administrative Authority.

Answer 23

3.15 L/s

Question 24

Minimum slope or pitch of horizontal drainage pipe - ______ (1/4” per foot).

Answer 24

2% or 20mm/m

Question 25

What are the 6 types of permissible traps?

Answer 25

1. common P-trap 2. deep seal trap 3. stand trap 4. bottle trap 5. running trap 6. drum trap

Question 26

____ is used for lavatories, kitchen sinks, laundry tubs, & urinals.

Answer 26

common P-trap

Question 27

What are the 4 materials commonly used for the P-trap?

Answer 27

1. nickel 2. chrome plated brass 3. galvanized malleable copper 4. PVC

Question 28

The seal of common P-trap is ____.

Answer 28

50 mm

Question 29

_____ water seal is about twice the size of the common P-trap.

Answer 29

deep seal P-trap

Question 30

_____ is used for extreme conditions because resealing equality is greater.

Answer 30

deep seal P-trap

Question 31

The seal for deep seal P-trap is _____.

Answer 31

7.5 cm

Question 32

____ is used for fixtures like slop sinks that are usually built low in the ground, leaving very little space for a foundation & a trap.

Answer 32

stand trap

Question 33

_____ serves as water seal & structural support for the fixture.

Answer 33

stand trap

Question 34

____ is perfect for small spaces under sinks that are cramped because of its shape.

Answer 34

bottle trap

Question 35

____ go straight up and down horizontal which maximizes space and makes it easy to maintain.

Answer 35

bottle trap

Question 36

____ is used within the line of house drain.

Answer 36

running trap

Question 37

Drum trap has a large diameter (around _____).

Answer 37

0.16 m

Question 38

____ is used for fixtures that discharge large amount of water (bathtubs, shower or floor drains).

Answer 38

drum trap

Question 39

What are 3 types of prohibited traps?

Answer 39

1. traps with movable parts or concealed interior partitions 2. no fixtures shall be double-trapped 3. S-trap

Question 40

_____ are predecessor of P-traps.

Answer 40

S-trap

Question 41

____ is used before traps has to connect to a ventilation line.

Answer 41

S-trap

Question 42

What are the 3 requirements of traps?

Answer 42

1. each plumbing fixture, except those with integral traps, shall be separately trapped with an approved-type water-sealed trap. 2. only one trap shall be permitted on a trap arm 3. one trap, centrally located, may serve three single compartment sinks or laundry tubs or lavatories, adjacent to each other and in the same room.

Question 43

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.

Answer 43

0.75 m

Question 44

The trap shall be _____ size as the trap arm to which it is connected.

Answer 44

the same

Question 45

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).

Answer 45

51 mm, 102 mm

Question 46

In the installation of traps, the vertical distance between a fixture outlet tailpiece and the trap weir shall not exceed _____ in length.

Answer 46

0.60

Question 47

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 _____.

Answer 47

1.8 m

Question 48

For trap arm 76 mm dia. or larger, a cleanout is required for a change of direction of greater than _____ deg.

Answer 48

22 1/2

Question 49

In no case shall the trap distance be less than _____ times the diameter of the trap arm.

Answer 49

2

Question 50

____ 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.

Answer 50

interceptors

Question 51

Interceptors shall have a water seal of not lesss than ____ deep.

Answer 51

152 mm

Question 52

What are the 4 types of interceptors?

Answer 52

1. grease interceptors 2. sand interceptors 3. solids interceptors 4. oil interceptor

Question 53

____ interceptors are limited to lavatories and sinks and must comply with the requirements of section 5.3.7.

Answer 53

drum trap solids interceptors

Question 54

What are the 5 requirements of clean-outs (required)?

Answer 54

1. at the upper terminal of every horizontal sewer or waste line 2. at each run of piping more than 15 meters (50 feet) in total developed length 3. at every 15 m (50 ft) of total developed length or a fraction thereof 4. additional clean-out shall be provided on a horizontal line with an aggregate offset angle exceeding 135° 5. 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.

Question 55

What are the 2 requirements of clean-outs (not required)?

Answer 55

1. on a horizontal drain less than 1.5 m in length unless such line is servinng sinks or urinals 2. 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)

Question 56

What are 6 examples of house drain appliances?

Answer 56

1. grease traps 2. house traps 3. drain tiles 4. garage traps 5. backflow valves 6. sewage ejectors

Question 57

_____ 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.

Answer 57

grease traps

Question 58

____ is used for establishments like restaurants, cafes, lunch counters, cafeterias, bars and clubs, hoteal hospital, sanitarium, factory or school kitchens.

Answer 58

grease traps

Question 59

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).

Answer 59

3.4 Liters, 1.3 L/s

Question 60

Each grease trap shall have an approved water seal of not less than ____ in depth or the diameter of its outlet, whichever is greater.

Answer 60

51 mm

Question 61

What are the 2 main types of grease trap?

Answer 61

1. earth cooled grease trap 2. mechanical grease trap

Question 62

_____ is placed in the house drain immediately inside the foundation wall of the building.

Answer 62

house traps

Question 63

Vents in house traps are minimum ____ the diameter of the building drain.

Answer 63

1/2

Question 64

____ is used to prevent groundwater from seeping through the basement walls & foundation.

Answer 64

drain tiles

Question 65

_____ areplaced around the perimeter of the foundation where water is collected.

Answer 65

hollow tiles

Question 66

____ are connected to the house draim and sump pit.

Answer 66

drain tiles

Question 67

____ a.k.a. garage catcch basin.

Answer 67

garage traps

Question 68

Operating principles: trap is filled with water & located at the lowest point of the garage so it can collect all wastes.

Answer 68

garage traps

Question 69

Operating principles (separation of grease from water): grease suspended in waste floats to the surface

Answer 69

grease traps

Question 70

____ is used in house drain to prevent the unliekly occurrence of backflows.

Answer 70

back flow valves

Question 71

____ works similar to check valves.

Answer 71

back flow valves

Question 72

____ pumps the wastes up from the sump pit to the sewers (which are usually higher than basement levels).

Answer 72

sewage ejectors