Above Ground Drainage

Question 1

What is the main purpose of a WC in a dwelling?

Answer 1

To remove human waste to the drainage system.

Question 2

What is the purpose of a wash hand basin?

Answer 2

To allow handwashing and general hygiene tasks.

Question 3

What is the purpose of a bath?

Answer 3

To provide a facility for body washing.

Question 4

What is the role of a bidet?

Answer 4

To allow for personal hygiene, specifically cleansing after use of toilet.

Question 5

What does a shower provide in terms of functionality?

Answer 5

Instantaneous and continuous washing using sprayed water.

Question 6

What is the primary function of a sink?

Answer 6

To wash dishes, hands, and food items in kitchens.

Question 7

What is the function of a urinal?

Answer 7

To receive and dispose of male urine.

Question 8

How does a conventional WC flush?

Answer 8

Using a gravity-fed cistern that releases water into the bowl.

Question 9

What helps maintain a water seal in WCs?

Answer 9

The trap at the base of the appliance.

Question 10

What allows a bath to retain water before draining?

Answer 10

A plug or pop-up waste.

Question 11

What is a primary ventilated stack system?

Answer 11

A single soil stack vented at the top to atmosphere.

Question 12

Where is a secondary ventilated stack used?

Answer 12

In taller buildings to avoid trap seal loss.

Question 13

What is a ventilated branch discharge system?

Answer 13

A branch pipework system with its own vent pipe.

Question 14

Name a major cause of trap seal loss.

Answer 14

Induced siphonage.

Question 15

What type of bend is used at the foot of a discharge stack?

Answer 15

A long radius bend.

Question 16

How far should low-level connections be from the stack foot?

Answer 16

At least 200mm above the bend.

Question 17

What is the usual size of a soil stack serving a WC?

Answer 17

110mm diameter.

Question 18

What size is typically used for a waste on a basin?

Answer 18

32mm depending on load.

Question 19

What is the max length for unvented branch pipework?

Answer 19

1.5m to 3m depending on pipe size and gradient.

Question 20

What gradient should waste pipework have?

Answer 20

18mm to 90mm per metre (1:40 to 1:20).

Question 21

Name one key regulation for sanitary installations.

Answer 21

The Water Supply (Water Fittings) Regulations 1999.

Question 22

What is the purpose of manufacturer’s instructions?

Answer 22

To guide correct installation and maintenance procedures.

Question 23

Give one example of building fabric prep before installing pipework.

Answer 23

Cutting floorboards to allow access.

Question 24

Name a protection measure for customer property.

Answer 24

Use of dust sheets and corner protectors.

Question 25

What material is common for domestic waste pipework?

Answer 25

uPVC.

Question 26

Name a common hand tool for sanitary work.

Answer 26

Pipe cutter.

Question 27

Why must access and egress routes be checked?

Answer 27

To ensure safe movement around the site.

Question 28

What PPE should be worn when handling waste pipes?

Answer 28

Gloves, safety glasses, and overalls.

Question 29

What is checked before selecting pipe fittings?

Answer 29

That they are the correct size and undamaged.

Question 30

What must be done before cutting into pipework?

Answer 30

Isolate water supply and assess for contaminants.

Question 31

What joint type uses a rubber ring for sealing?

Answer 31

Ring seal joint.

Question 32

What joint type uses chemical bonding?

Answer 32

Solvent weld joint.

Question 33

What is a pan connector used for?

Answer 33

To connect a WC outlet to a soil pipe.

Question 34

How is thermal expansion managed in plastic pipes?

Answer 34

By using expansion joints or clips allowing movement.

Question 35

How far apart should brackets be on horizontal pipes?

Answer 35

Every 1m for plastic pipes.

Question 36

What type of drainage system handles all foul and surface water together?

Answer 36

Combined system.

Question 37

What is a stub stack?

Answer 37

A short unvented soil stack for ground floor appliances.

Question 38

How should multiple wastes connect into a stack?

Answer 38

Using a manifold or swept branch fittings.

Question 39

How is a flushing cistern tested post-installation?

Answer 39

By flushing it and checking for leaks or weak flow.

Question 40

Name a requirement when fixing a bath.

Answer 40

Level installation with adequate support brackets.

Question 41

What is used to block access before work is complete?

Answer 41

Warning signage and capping unused connections.

Question 42

What is checked during visual pipe inspections?

Answer 42

Leaks, support spacing, and material condition.

Question 43

What do you do if a trap seal is lost?

Answer 43

Investigate cause and install self-sealing valve if needed.

Question 44

Name a typical maintenance issue with urinals.

Answer 44

Blocked waste due to limescale buildup.

Question 45

What info goes on a maintenance record?

Answer 45

Date, issue, repair, engineer’s name, and parts used.

Question 46

How can disruption during decommissioning be minimised?

Answer 46

Complete prep before isolating services.

Question 47

How should pipework be made safe during decommissioning?

Answer 47

By using caps and placing warning notices.

Question 48

Why must you inform others before decommissioning?

Answer 48

To allow them to make alternative arrangements.

Question 49

What is checked in a visual inspection before testing?

Answer 49

All joints, brackets, appliance connections, and caps.

Question 50

What is used to perform an air test?

Answer 50

A u-gauge and air pump to detect pressure loss.