Plumbing Mid Term

Question 1

What is the minimum size of a secondary stack vent in a commercial building serving a 3” soil stack?

Answer 1

1 1/2”

Question 2

What is the maximum number of circuit vented branch traps that can be installed between a circuit vent and a relief vent?

Answer 2

8 traps

Question 3

What is the minimum size of a relief vent?

Answer 3

One size smaller then the circuit vent

Question 4

The National Plumbing Code is a set of written standards which:

Answer 4

set minimum standards

Question 5

What is the minimum size individual vent serving a 4” trap?

Answer 5

1 ½”

Question 6

What is the maximum length of a 3” trap arm serving a floor drain at minimum grade?

Answer 6

3.75m (12’)

Question 7

When is a backwater valve required?

Answer 7

on fixtures below grade

Question 8

The flow from a pump into a storm drainage system is taken as:

Answer 8

1 L/s = 900 L

Question 9

What size storm building drain is required for a flat roof of 20m long and 18m wide at 1 in 100 slope?

Answer 9

6”

Question 10

What size leader is required for a flat roof of 11m long and 20m wide?

Answer 10

4”

Question 11

What CCC protection is required for the Washdown Ventilation Hood?

Answer 11

RP

Question 12

The Flight Machine (A) has an operating temperature of 77 deg C for pumping water through equipment for at least ___________.

Answer 12

5 MIN

Question 13

What is the minimum size branch discharging from the Food Display Sink?

Answer 13

1 1/4”

Question 14

What are the names of the R’s in the food prep sink?

Answer 14

Non-concealed standing wastes

Question 15

According to the plumbing code, what would be the fixture unit load for a flow rate of 12 imperial gallons per minute?

Answer 15

29 fu’s

Question 16

What is the purpose of the Orifice Flow Control Plate (M)?

Answer 16

CONTROL THE LAMINAR FLOW INTO THE TRAP

Question 17

What is the maximum number of flush tank water closets that could drain from the fifth storey into a 3” soil stack?

Answer 17

4

Question 18

Piping that is too low to drain by gravity into the sanitary building drain is called:

Answer 18

Sub drainage piping

Question 19

How is the size of a vent for a sewage pump determined?

Answer 19

one size smaller than the largest inlet, at least 2” but no more than 4”

Question 20

When sizing a combined sewer, how do you convert from FU to litres?

Answer 20

260 FU and more multiply by 9.1, under 260 is counted as 2360

Question 21

What is the maximum number of fixture units that may drain into a soil or waste pipe used as an alternate relief vent?

Answer 21

6

Question 22

What is the minimum height (in inches) of a vent terminal above the flashing?

Answer 22

6

Question 23

An offset relief vent for soil stack offsets is required when the upper portion of the stack passes through more than 2 storeys and receives a FU load of more than?

Answer 23

100

Question 24

What is the minimum size cleanout serving a 4” branch?

Answer 24

3”

Question 25

A trap is required for a subsoil drainage pipe if:

Answer 25

it drains into a combined sewer

Question 26

What is the maximum number of FU’s that may drain into a vent stack at the lowest storey?

Answer 26

8 FU

Question 27

A 4” circuit vented branch with 3 water closets and 25 FU discharging above and downstream will be used as an alternate relief vent. True or False?

Answer 27

False

Question 28

What is the minimum size of the stack for a branch with a load of 3 FU drained from the tenth floor?

Answer 28

2"

Question 29

A vent stack is needed when fixtures discharge from _____ or more storeys.

Answer 29

5

Question 30

The fixtures that may drain into a vent stack must be located:

Answer 30

on the lowest storey it serves

Question 31

A vent stack shall connect to the soil and waste stack:

Answer 31

at or below the lowest soil pipe connection

Question 32

Yoke vents for vent stacks are required when a soil or waste stack receives discharge from fixtures located on more than how many stories?

Answer 32

11

Question 33

If a continuous appliance has pumped discharge of 20 L/s, what would be its fixture unit rating?

Answer 33

20 x 31.7

Question 34

When sizing a combined sewer, a sanitary FU load of 195 would be considered equal to how many litres?

Answer 34

2,360 L

Question 35

Combined sewers are always sized by:

Answer 35

converting fu to litres

Question 36

The minimum size of a yoke vent for vent stacks is:

Answer 36

One size smaller than the smallest pipe to which it is connected

Question 37

A service sink is installed with a:

Answer 37

2" p trap

Question 38

A soil-or-waste pipe may serve as a wet vent provided that the total discharge from any one storey above the first storey does not exceed _______ fixture units.

Answer 38

4

Question 39

A soil-or-waste pipe may serve as a wet vent provided the offset does not exceed ____m for pipes larger than 2 inches in size.

Answer 39

2.5

Question 40

A circuit-vented branch shall be not less than ______ inches, where traps 2 inches in size or larger are circuit-vented.

Answer 40

3

Question 41

Additional circuit vents shall be required where more than ______ circuit-vented fixtures are connected to a branch between vent pipe connections.

Answer 41

8

Question 42

A soil-or-waste pipe may serve as an additional circuit vent in provided it is sized as a wet vent and is not less than _________ inches in size.

Answer 42

2

Question 43

A section of horizontal branch may be circuit-vented provided no soil-or-waste stack is connected to it _____________ of a circuit-vented fixture.

Answer 43

Upstream

Question 44

The roof is 18m x 14m, the adjacent wall is 4m x 14m and rainfall is 23mm/15min. What is the minimum size of RWL?

Answer 44

4"

Question 45

What is the hydraulic load of a commercial washing machine with a semi-continuous flow of 1.5L/s?

Answer 45

180 FU

Question 46

If a fixture has a continuous flow of 0.8L/s, what is the hydraulic load at # 16?

Answer 46

25 FU

Question 47

What kind of sump is illustrated at # 23?

Answer 47

Storm sump

Question 48

What size is the wet vent portion of a relief vent for a circuit vented branch with 3 - 2 headed showers. 1 - 3" emergency floor drain and 2 closed coupled WC. The wet vent portion of the RV had 2 lavs draining into it.

Answer 48

2"

Question 49

A commercial dishwasher is set at what temperature range for the sanitizing cycle?

Answer 49

170-185 deg f ## Footnote This temperature range is critical for effective sanitization.

Question 50

While getting your hair cut, what CCC device protects the hair salon faucet?

Answer 50

vacuum breaker ## Footnote A vacuum breaker prevents backflow in plumbing systems.

Question 51

What is another name for an accuflow parabolic weir?

Answer 51

flow control roof drain ## Footnote This device helps manage water flow on roofs.