Sanitary drainage (Discharged drainage)

Question 1

what are the terms in soil and waste system?

Answer 1

• drainage above ground
• discharged stack
• soil pipe
• waste pipe
• Macerate

Question 2

what is discharged stack?

Answer 2

vertical pipe conveying foul fluid/ solid

Question 3

macerate

Answer 3

1. to soften and separate into parts by steeping in liquid
2. to soften or decompose (food) by the action of solvent .
3. to cause to grow thin

Question 4

tough copolymers used especially for making moulded particle

Answer 4

ABS,acrylonitrile-butadiene-styrene

Question 5

DR- drainage installations should be remove?

Answer 5

effluent quickly and quietly

Question 6

DR-free from?

Answer 6

blockage

Question 7

how does blockage occur?

Answer 7

• system is overloaded with solids
• become frozen
• suffer restricted flow at poorly constructed bend/joints
• or has building material left inside pipe

Question 8

each section of pipe must be what?for?

Answer 8

must be accessible for inspection and internal cleaning

Question 9

DR- be durable?

Answer 9

last as long as it can unless new technology or requirements are needed

Question 10

DR- economic

Answer 10

save money

Question 11

single stack system was developed by?

Answer 11

Building research establishment during 1960s

Question 12

why single stack system is developed?

Answer 12

to simplify the extensive pipe work that was associated with above ground drainage

Question 13

what is the concept of singles stack system

Answer 13

to group appliances around the stack with seperate branch pipe serving each.

Question 14

length of waste trap must be?

Answer 14

75mm

Question 15

length of waste trap for bath and shower

Answer 15

50mm

Question 16

if offsets is unavoidable, there should be?

Answer 16

no connection within 750mm of the offtsets

Question 17

the branch bath waste must be? purpose? and require?

Answer 17

200mm below the centre of WC branch, to avoid crossflow, and require 50mm nom. dia. parallel pipe to offset the bath waste pipe or an S trap to offset the connection.

Question 18

when the vent pipe is at the highest stack, it may reduced to?

Answer 18

75mm nom. dia.

Question 19

modification of single stack system, what are they?

Answer 19

• waste pipe may be fitted with anti-siphon or resealing
• branch waste pipe can be ventilated
• larger than standard dia. waste pipe may be fitted

Question 20

where does ventilated stack system is used?

Answer 20

in building where close grouping of appliances occur

Question 21

modified single stack system, requirement for WC

Answer 21

• 8 maximum
• 100mm branch pipe nom. dia.
• 15m max. length
• gradient 90 1/2 and 95 degree (9 to 90mm/m)

Question 22

modified single stack system, requirement Basin

Answer 22

• 4 max
• 50mm pipe nom. dia.
• 4m max. length
• gradient 91-92 1/2 degree (18 and 45 mm/m)

Question 23

modified single stack system, requirement Urinals(bowls)

Answer 23

• 5 max
• 50mm pipe nom. dia
• branch pipe as short as possible
• gradient 18-90mm/m

Question 24

modified single stack system, requirement Urinals( stalls)

Answer 24

• 7 max
• 65mm pipe nom. dia.
• branch pipe as short as possible

Question 25

where do fully vented appliances usually occur?

Answer 25

where there are large range of sanitary appliances eg. schools factory, hospital, offices

Question 26

anti-siphon or vent pipe must be connected within?

Answer 26

300mm of the crown of the trap

Question 27

the base of the vent stack should be connected to what? why?

Answer 27

should be connected to the discharged stack close to the bottom rest bend, to relieve any compression

Question 28

collar boss single stack system is developed by?

Answer 28

Marley company

Question 29

what is the purpose of collar boss?

Answer 29

for connection of waste pipe with discharged stack without the interference of crossflow

Question 30

advantage of collar boss ?

Answer 30

simplifies the bath waste connection, less structurally disruptive

Question 31

loop vents may not be required when?

Answer 31

branch waste are kept minimal lengths

Question 32

modern terms for soil pipes

Answer 32

discharged pipes

Question 33

modern term for waste pipe

Answer 33

dicharged stacks

Question 34

disadvantage of two pipes system

Answer 34

-expensive

Question 35

two pipes system can be used where?

Answer 35

when the sanitary appliances are widely spaced

Question 36

small bore pump system is useful for?

Answer 36

where the location of sanitary appliances is impractical