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Flashcards in Chpt 4 Deck (72)
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1
Q

The basic plan for fighting most fires depends on having an adequate supply water to confine, control, and

A

Extinguish the fire

2
Q

Ensuring a dependable _______is a critical fire ground operation that must be accomplished as soon as possible

A

Water supply

3
Q

At Any scene, you will obtain water from one of two means;

A

Pressurized systems and Static water sources

4
Q

Pressurized sources may be either ______ which furnish water under pressure through fire hydrants

A

Municipal water systems or private water systems

5
Q

Are sources such as lakes, ponds, rivers, and streams.

A

Static water supplies

6
Q

The establishment of an adequate, continuous _____ then becomes a primary objective to support the fire attack

A

Water supply

7
Q

Approximately _____ percent of the earths surface is covered by water .

A

70 to 75

8
Q

The ______ allows water to flow, puddle, and remain together even after leaving the nozzle

A

Surface tension

9
Q

As water passes through or moves by a substance, the positive and negative charges of the molecule take the various chemicals, minerals, and solvents along with it, thus earning water the title of ____

A

Universal solvent

10
Q

Water has been used as the primary extinguishing agent in the fire service from the earliest days, mostly because of its

A

Wide spread availability

11
Q

The amount of heat energy required to increase the temperature of a substance is known as its

A

Specific heat index

12
Q

Waters specific heat index is

A

1

13
Q

Water absorbs almost ____ more heat than sodium bicarbonate

A

5 times

14
Q

Water in its liquid form weighs 8.3 pounds per gallon, adding ______ of weight to the chassis of an engine with a 750 gallon tank.

A

6248 pounds

15
Q

Whereas its high heat absorption allows water to have notable cooling effects, water may be also converted to gas through the application of heat, an effect attributable to its high ______

A

Heat of vaporization

16
Q

Water at ___ is almost one half pound heavier than water at 100F

A

32 F

17
Q

The volume of water vapor is _____ times greater than that of an equal amount of liquid water; as a consequence, water displaces oxygen and effectively smothers the fire.

A

1700 times

18
Q

The amount of particulate matter suspended in water is known as ____

A

Turbidity

19
Q

The color of water is is directly related to the level of _____ present

A

Turbidity

20
Q

The amount of dissolved calcium and magnesium which increases the mineral content within water, determines the waters

A

Level of hardness

21
Q

Takes place when two dissimilar metals are immersed in water

A

Galvanic corrosion

22
Q

Prevent or limit the flow between the two metals, thus limiting the erosion or pitting of the metals

A

Sacrificial anodes

23
Q

Municipal water systems can draw water from wells, rivers, streams, lakes, or human made storage facilities called

A

Reservoirs

24
Q

Municipal water systems also include a _________, where impurities from the water are removed

A

Water treatment facility

25
Q

The distribution system delivers water from the treatment facility to the end users and fire hydrants through a complex network of underground pipes, known as

A

Water mains

26
Q

Driver operators must understand their water distribution systems and typical operating pressures; however it is recommended that hydrant have a minimum operating pressure of

A

20 psi

27
Q

Most ______rely on an arrangement of pumps to provide the required pressure, either directly or indirectly

A

Water distribution systems

28
Q

Most municipal systems have multiple pumps and back up power supplies to reduce the risk of a service interruption due to a

A

Pump failure

29
Q

In a _____, the water source, treatment plan, and storage facilities are located on Highground while the end-users live in lower lying areas, such as a community in a valley

A

Gravity feed system

30
Q

Most municipal water supply systems use a combination of _______to deliver water.

A

Pumps and gravity

31
Q

Large mains, known as_______, carry large quantities of water to a section of the town or city.

A

Primary feeders

32
Q

Smaller mains, called _______, distribute the water to a smaller area.

A

Secondary feeders

33
Q

Water mains in a well designed system will follow a _____

A

Grid pattern

34
Q

A _______ provides water flow to a fire hydrant from two or more directions and establishes multiple paths from the source to each area.

A

Grid arrangement

35
Q

Some water distribution systems may have ______, which supply water from one direction

A

Dead end mains

36
Q

If two or more hydrant on the same dead end main are used to fight a fire, the upstream hydrant will have more water and water pressure than the

A

Downstream hydrants

37
Q

Installed at intervals throughout a water distribution system allow different sections to be turned off or isolated

A

Control valves

38
Q

Are located at the connection points where the underground mains meet the distributor pipes.

A

Shut off valves

39
Q

If the water system in the building or to a fire hydrant is damaged, firefighters can close the _______ to prevent further water flow

A

Shut off valves

40
Q

Refers to the force per unit area, and is measured in psi.

A

Water pressure

41
Q

The water flow or quantity of water moving through a pipe, hose, or fittings is measured by its _____, usually in terms of gallons per minute

A

Volume

42
Q

Water that is not moving has ____

A

Potential energy and kinetic energy

43
Q

Fluid pressure is exerted perpendicular to any surface on which it acts

A

Principle 1

44
Q

Pressure in fluid acts equally in all directions

A

Principle 2

45
Q

Pressure applied to a confined fluid from without is transmitted equally in all directions

A

Principle 3

46
Q

The pressure of a liquid in an open vessel is proportional to the depth of the liquid

A

Principle 4

47
Q

The pressure of a liquid in an open container is proportional to the density of the liquid

A

Principle 5

48
Q

Liquid pressure on the bottom of a container is unaffected by by the size and shape of the container

A

Principle 6

49
Q

Is the pressure in a system when the water is not moving

A

Static pressure

50
Q

Static pressure is ______, because it would cause the water to move if there were some place the water could go.

A

Potential energy

51
Q

Static pressure is generally created by

A

Elevation pressure or pump pressure

52
Q

An elevated storage tank creates _____ in water mains

A

Elevation pressure

53
Q

For the driver operator, elevation refers to the position of the _____ as it relates to the nozzle

A

Pump

54
Q

Atmospheric pressure decreases approximately ____ for every 1000 ft that the geographic location rises above sea level.

A

0.5 psi

55
Q

Placing a pressure gauge on the hydrant port and opening the hydrant valve can measure _______ in a water distribution system

A

Static pressure

56
Q

Refers to the amount of pressure in the water distribution system during a period of normal consumption

A

Normal operating pressure

57
Q

Is the amount of pressure that remains in the system when the water is flowing

A

Residual pressure

58
Q

When you open a hydrant and start to draw large quantities of water out of the system, some of the potential energy of the Still water is converted into the _____ of moving water.

A

Kinetic energy

59
Q

is an important measurement because it provides the best indication of how much more water is available in the system

A

Residual pressure

60
Q

In theory, when the maximum amount of water is flowing, the residual pressure is ____, and there is no more potential energy to push water through the system.

A

zero

61
Q

In the fire service, _____ is considered the minimum usable residual pressure, as this level reduces the risk of damage to underground water mains or pumps.

A

20 psi

62
Q

Is the forward pressure measured at a discharge opening while water is moving

A

Flow pressure

63
Q

To calculate the volume of water flowing, use a _____ to measure the pressure at the center of the water stream as it passes through the opening and then factor in the size and flow characteristics of the orifice

A

Pitot gauge

64
Q

When water is flowing through hoses, pipes, and fittings, the water is slowed by the contact it has with the walls of the hose or pipe, which resulted in

A

Friction loss

65
Q

Is a pressure surge or wave caused by the kinetic energy of a fluid in motion when it is forced to stop or change direction suddenly

A

Water hammer

66
Q

Are used in climates where temperatures can be expected to fall below the freezing level

A

Dry barrel hydrants

67
Q

Are used in locations where the temperatures do not drop below the freezing mark

A

Wet barrel hydrants

68
Q

Fire hydrants maybe place a certain distance apart, about every ____feet in residential areas and ____feet in high-value commercial and industrial areas

A

500 residential

300 high value

69
Q

Hydrant flow testing should be conducted during the water distribution systems ______

A

Peak flow times

70
Q

Also provide quick and reliable access to static water sources

A

Dry hydrants

71
Q

Are often installed in lakes and rivers and close to clusters of buildings where there is a recognize need for fire protection

A

Dry hydrant

72
Q

Dry hydrant should be flow tested at least on an annual basis and should be ______prior to use

A

Backed flushed