Chapter 6 What is Water and Where Does It Come From Flashcards Preview

IFSTA Pumping Apparatus Driver/Operator > Chapter 6 What is Water and Where Does It Come From > Flashcards

Flashcards in Chapter 6 What is Water and Where Does It Come From Deck (60):
1

Water is a compound of hydrogen and oxygen formed when:

two hydrogen atoms combine with one oxygen atom.

2

Water exists in a liquid state between:

32ºF and 212ºF (0ºC and 100ºC)

3

Water converts to a solid state (ice) below:

32ºF (0ºC)

4

Water converts to steam above:

212ºF (100ºC)

5

Water is lightest close to its boiling point – weighing approximately:

60 lb/ft3 (0.96 kg/L).

6

For fire protection purposes, ordinary fresh water is generally considered to weigh:

8.33 lb/gal (1kg/L)

7

What is specific heat?

A measure of the heat-absorbing capacity of a substance

8

What unit is used to measure amounts of heat transfer?

British thermal unit (Btu) or joule (J)

9

What is a Btu?

The heat required to raise the temperature of 1 pound of water 1ºF

10

What unit of measurement has the joule taken the place of in the SI (International System of Units)?

Calorie

11

The latent heat of vaporization is:

The quantity of heat absorbed by a substance when it changes from a liquid to a vapor

12

What is the name for the temperature at which a liquid absorbs enough heat to change to a vapor?

Boiling point

13

Vaporization does not completely occur at boiling point. Each pound of water requires approximately ___ Btu (kJ) of additional heat to completely convert into steam.

970 Btu (1 023 kJ)

14

Approximately how much does water expand beyond its original volume when converted to steam at 212ºF (100ºC)?

1,700 times

15

The speed with which water absorbs heat increases in proportion to:

the water surface exposed to the heat.

16

Steam expansion is ___ inside a burning building.

rapid

17

What is specific gravity?

The density of liquids in relation to water

18

What kinds of liquids are lighter than water and therefore float on water?

Those with a specific gravity less than 1

19

What kinds of liquids are heavier than water and sink to the bottom?

Those with a specific gravity greater than 1

20

Most flammable liquids have a specific gravity of:

less than 1

21

How much pressure is required to reduce the volume of water one percent?

30,000 psi (210 000 kPa)

22

Friction loss in a system ___ as the length of hose or piping ___.

increases/increases

23

Flow pressure will always be ___ near the supply source and ___ at the farthest point in the system.

greatest/lowest

24

If an opening is made directly at the hydrant, as opposed to the nozzle, the flow will be much ___ at a ___ pressure.

greater/higher

25

If velocity is increased beyond practical limits, the friction becomes so great that resistance agitates the entire stream, creating:

critical velocity.

26

What is water hammer?

The sudden stopping of water moving through a hose or pipe resulting in an energy surge being transmitted in the opposite direction, often at many times the original pressure

27

Close nozzles, hydrants, valves, and hose clamps ___ to prevent water hammer.

slowly

28

Equip apparatus inlets and remote outlets with ___ to prevent damage to equipment.

pressure relief devices

29

High-volume systems should be protected with:

dump valves.

30

Where can the primary water supply be obtained?

Surface water or groundwater

31

Which of the following is NOT a means of moving water?

A. Gravity system
B. Treatment system*
C. Combination system
D. Direct pumping system

32

Which means of moving water uses one or more pumps that take water from the primary source and discharge it through the filtration and treatment processes?

Direct pumping system

33

Which means of moving water uses a primary water source located at a higher elevation than the distribution system?

Gravity system

34

What is the fire department's main concern regarding treatment facilities?

hat a maintenance error, natural disaster, loss of power supply, or fire could disable the pumping stations

35

From where does the water supply distribution system receive water?

From the pumping station

36

When water flows through pipes, its movement causes friction that results in a reduction of pressure. There is much less pressure loss in a water distribution system when fire hydrants are supplied:

from two or more directions.

37

A fire hydrant that receives water from only one direction is known as a:

dead-end hydrant.

38

A fire hydrant that receives water from two or more directions is known as a:

looped line.

39

A distribution system that provides circulating feed from several mains constitutes a:

grid system.

40

___ are large pipes (mains) with relatively widespread spacing, that convey large quantities of water to various points of the system for local distribution to the smaller mains.

Primary feeders

41

___ make up a network of intermediate-sized pipes that reinforce the grid within the various loops of the primary feeder system and aid the concentration of the required fire flow at any point.

Secondary feeders

42

___ make up a grid arrangement of smaller mains serving individual fire hydrants and blocks of consumers.

Distributors

43

To ensure sufficient water, two or more primary feeders should run from the source of supply to the ___ districts of the community by separate routes.

high-risk and industrial

44

In residential areas, the recommended size for fire hydrant supply mains is at least 6 inches (150 mm) in diameter. These should be closely gridded by 8-inch (200 mm) cross-connecting mains at intervals of not more than:

600 feet (180 m).

45

In the business and industrial districts, the minimum recommended size is a(n) ___ main with cross-connecting mains every 600 feet (180 m).

8-inch (200 mm)

46

___ mains may be used on principal streets and in long mains not cross-connected at frequent intervals.

12-inch (300 mm)

47

Water mains as large as ___ may be found in major cities.

48 inches (1.2 m)

48

What is the function of a valve in a water distribution system?

To provide a means for controlling the flow of water through the distribution piping

49

Valves should be operated at least ___ to keep them in good condition.

once a year

50

Valve spacing should be such that:

only a minimum length of pipe is out of service at one time.

51

Which type of valve shows whether the gate or valve seat is open, closed, or partially closed?

Indicating valve

52

Which type of valve is a hollow metal post that is attached to the valve housing?

Post indicator valve

53

Which type of valve has a yoke on the outside with a threaded stem that controls the gate's opening or closing?

Outside screw and yoke

54

Which types of valves are the most common types of valves used on most public water distribution systems?

Nonindicating valves

55

Valves that are only partially open cause:

high friction loss.

56

Which of the following is NOT a material commonly used to make water pipes?

A. Steel*
B. Plastic
C. Concrete
D. Cast iron

57

Friction loss of pipes is most frequently increased by:

encrustation of minerals on the interior surfaces of the pipe.

58

Friction loss can be reduced by:

flushing hydrants periodically.

59

Private water supply systems are NOT normally found on:

fire protection properties.

60

Which of the following statements about private water supply systems is FALSE?

A. Private water supply systems are most often found in residential developments.*
B. The design of private water supply systems is typically similar to that of municipal systems.
C. Private water supply systems may service one large building or a series of buildings on the complex.
D. Most private water supply systems separate piping for fire protection and domestic/industrial services.