Week 2 Tanks

Question 1

Max size of a wood tank

Answer 1

5000-100000gal

Question 2

Capacity of steel tanks

Answer 2

5000-500,000gal

Question 3

Capacity of concrete tanks

Answer 3

10,000-1,000,000gal

Question 4

Schedule of steel pipe

Answer 4

2” minimum
2”-5” sch 80
6” and up sch 40

Question 5

Water level gauge

Answer 5

Required for all tanks
Mercury gauges were original method
Current methods:
Altitude gauge
Float type water level indicator
Tank level switch

Question 6

Types of tanks discussed this week

Answer 6

Gravity tank
Suction tank
Break tank
Pressure tank

Question 7

Purpose of water tanks

Answer 7

To provide fire protection systems with adequate volume and pressure to meet system demands

Question 8

Which NFPA covers tanks?

Answer 8

NFPA22

Question 9

Size of settling basin in a flat bottom tank

Answer 9

4”

Question 10

Size of settling basin in a suspended bottom tank

Answer 10

18”

Question 11

Size of settling basin in a large tank riser

Answer 11

36”

Question 12

What supports the riser in a gravity tank?

Answer 12

Base elbow

Question 13

What is the minimum size of a discharge pipe?

Answer 13

6”
Unless pressure tank which is 4”

Question 14

Offset in piping should be

Answer 14

Avoided

Question 15

Where should the check valve be installed?

Answer 15

In the valve pit below the tank

Question 16

What orientation should the check valve be installed in?

Answer 16

Horizontally

Question 17

Where is the control valve installed

Answer 17

In the valve pit below the tank before the check and on the yard side of the check

Question 18

How many control valves shall be installed?

Answer 18

2 around the check

Question 19

Where are the control valves installed in relation to the check valve

Answer 19

Each side

Question 20

How can you tell if the control valve is open or closed?

Answer 20

The control valves shall be indicating

Question 21

For gravity tanks how long should the tank take to fill

Answer 21

8 hours

Question 22

What should the water level of the gravity tank be maintained at?

Answer 22

Full
Never more than 4” below full line

Question 23

How do you fill a gravity tank?

Answer 23

Bypass around the check
Or
Separate filling pump

Question 24

A bypass around the check is necessary when:

Answer 24

Filling from city pressure
2” pipe connection
Indicating valve is kept closed unless filling

Question 25

Separate filling pump is required when

Answer 25

Separate water supply for pump

Question 26

What valves must be on a separate filling pump?

Answer 26

Check valve and control valve which is only open while filling

Question 27

Where are roof vents required?

Answer 27

Airtight steel roofs

Question 28

What is the size of the air vent?

Answer 28

1/2 the area of the discharge or fill pipe, whichever is larger

Question 29

What does an air vent require?

Answer 29

A screen to protect from outside contaminants ie: nesting birds

Question 30

Can an overflow pipe be used as a vent?

Answer 30

No

Question 31

Does an overflow pipe drain faster or slower than a fill pipe?

Answer 31

Faster

Question 32

What is the size of an over flow pipe?

Answer 32

1 pipe size greater than the fill pipe not less than 3"

Question 33

Where is the inlet to overflow on the tank?

Answer 33

Top capacity line of the tank

Question 34

What is attached to the inside top of the overflow pipe?

Answer 34

A concentric reducer ie: 4"x3" reducer with the large part of the cone facing up

Question 35

What is the minimum size drain on a gravity tank?

Answer 35

2"

Question 36

What size ball drip and what is it's function on the drain?

Answer 36

1/2" ball drip to auto drain trapped sections

Question 37

What do you need with the drain?

Answer 37

2½" hose connection to capture and move the water if necessary.

Question 38

What is the minimum temperature allowed in a gravity tank

Answer 38

40°F

Question 39

Name 2 things supervised in a gravity tank

Answer 39

Water temp and level

Question 40

What is the purpose of a gravity tank?

Answer 40

Use elevation as a source of pressure