Chapter # 6 What is Water and Where does it come From?

Question 1

Water is considered to be incompressible, and its weight varies at what?

Answer 1

Different Temps

Question 2

Waters weight per unit of volume.

Answer 2

Water Density

Question 3

What is the weight of water in its three forms of matter?

Answer 3

Close to frozen = 62.4 lbs per cubic foot
Close to boiling = 60 lbs per cubic foot
Ordinary fresh water = 62.5 lbs per cubic foot.

Question 4

What is the weight of one gallon of water?

Answer 4

8.33 lbs

Question 5

Water can be used to smother combustible fuel fires, that involves combustible fuels who’s specific gravity is what?

Answer 5

Higher then 1

Question 6

As a extinguishing agent what four things does water depend on?

Answer 6

Specific Heat. Latent Heat of Vaporization. Exposed Surface Area. Specific Gravity.

Question 7

A measure of heat absorbing capacity of a substance.

Answer 7

Specific Heat

Question 8

Amounts of heat transfer can be measure in these two ways.

Answer 8

BTU’s and Joules

Question 9

The amount of heat required to raise the temp of 1 lbs of water 1 degree.

Answer 9

BTU

Question 10

The joule is a measure of work that has replaced what in the SI?

Answer 10

The calorie

Question 11

T or F The specific heat of any substance is the ratio between the amount of heat needed to raise the temp of a specific quantity of a material and the amount of heat needed to raise the temp of a identical quantity of water by the same number of degrees.

Answer 11

True

Question 12

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

Answer 12

Latent Heat of Vaporization

Question 13

How many more BTU’s does it require to turn water into steam after it reaches its boiling point?

Answer 13

970 BTU’s

Question 14

How many BTU’s does it take to get 1 gallon of water to 212 F? How many BTU’s does it take to get 1 gallon of water to turn to steam?

Answer 14

1,266 BTU’s. 9,346 BTU’s.

Question 15

The rate at which a object gives off heat depends on these three factors.

Answer 15

Physical form. Amount of surface area exposed. Air or Oxygen Supply.

Question 16

The speed at which water absorbs heat increases in proportion to what?

Answer 16

The water surface exposed to heat.

Question 17

At 212 F how many times its original volume does water expand?

Answer 17

1700 times

Question 18

Name three observable results that a water fire stream is being effective in a room.

Answer 18

Fire is extinguished or reduced in size. Visibility maintained. Room temp reduced.

Question 19

The tendency of a liquid to possess internal resistance to flow.

Answer 19

Viscosity

Question 20

The density of a liquid in relation to water.

Answer 20

Specific Gravity

Question 21

If a specific liquid other then water, has a specific gravity of 1 what will happen?

Answer 21

It mixes evenly with water.

Question 22

What is the specific gravity of most flammable liquids?

Answer 22

Less then 1.

Question 23

What are some disadvantages of using water as a extinguishing agent?

Answer 23

High surface tension that makes it hard to penetrate dense materials. May be reactive with certain fuels such as some metals. Low level of opacity and reflectivity which allows radiant heat to pass through it. Water freezes. Readily conducts electricity.

Question 24

Force per unit area.

Answer 24

Pressure

Question 25

A measure of weight as it is related to the force of gravity.

Answer 25

Force

Question 26

***A 1 square inch column of water that is 1 foot height exerts how much pressure at the base?

Answer 26

0.434

Question 27

***How many feet of a square 1" column of water is needed to equal 1 psi at the base?

Answer 27

2.304

Question 28

The speed at which a fluid travels through a hose or pipe is determined by the pressure upon that fluid. The speed that the fluid travels is called what?

Answer 28

Velocity

Question 29

There are ......... principles that determine the action of pressure upon fluids.

Answer 29

six

Question 30

First principle: Fluid pressure is ..........to any surface on which it acts.

Answer 30

Perpendicular

Question 31

Second principle: Fluid pressure at a point in a fluid at rest is the same intensity in all ..........

Answer 31

Directions

Question 32

Third Principle: Pressure applied to a confined fluid from without is transmitted equally in ......... This is only true if there is no change in elevation of the container (stand pipe).

Answer 32

all directions.

Question 33

Fourth Principle: The pressure of a liquid in a open vessel is proportional to its..........

Answer 33

Depth.

Question 34

Fifth Principle: The pressure of a liquid in an open vessel is proportional to the ............of the liquid.

Answer 34

Density (water vs mercury)

Question 35

Sixth Principle: The pressure of a liquid on the bottom of a vessel is independent of the ..............of the vessel.

Answer 35

Shape

Question 36

What is considered standard atmospheric pressure?

Answer 36

14.7 psi

Question 37

What does PSIG stand for?

Answer 37

Pounds per square inch gauge.

Question 38

Any pressure less then atmospheric pressure is called what? Absolute zero pressure is called what?

Answer 38

Vacuum. Perfect Vacuum.

Question 39

The height of a water supply above the discharge orifice.

Answer 39

Head

Question 40

To convert head in feet to head in pressure, divide the number of feet by what?

Answer 40

2.304

Question 41

Stored potential energy available to force water through pipes, fittings, fire hose, and adapters. At rest with no motion.

Answer 41

Static

Question 42

Pressure found in a water distribution system during normal consumption demands.

Answer 42

Normal Operating Pressure

Question 43

That part of the total available pressure not used to overcome friction loss or gravity while forcing water through pipes, fittings, fire hose, and adapters. Remainder of what is left.

Answer 43

Residual Pressure

Question 44

Residual pressure is identified at the location of the reading, not at the what?

Answer 44

flow hydrant

Question 45

Forward velocity pressure at a discharge opening while water is flowing.

Answer 45

Flow pressure (velocity pressure)

Question 46

If the size of a opening is known, a measurement of flow pressure can be used to obtain what?

Answer 46

Quantity of water flowing. GPM

Question 47

The center line of the pump or the bottom of a static water supply source above or below ground.

Answer 47

Elevation

Question 48

The position of a object above or below sea level.

Answer 48

Altitude

Question 49

Pressure loss and pressure gain are refereed to as what?

Answer 49

Elevation pressure

Question 50

Atmospheric pressure decreases approximately 0.5 psi for every ..........feet above sea level.

Answer 50

1000'

Question 51

List six causes of friction loss in fire hose.

Answer 51

Movement of water molecules against each other. Lining of fire hose. Couplings. Sharp bends. Change in hose size or orifice. Improper gasket size.

Question 52

The friction loss in old hose may be how much percent greater then in new hose?

Answer 52

50%

Question 53

Commonly referred to as the "coefficient of friction".

Answer 53

Inner surface of a pipe.

Question 54

How many principles govern friction loss in hose or pipes?

Answer 54

Four

Question 55

First Principle of FL: If all other conditions are the same, friction loss varies directly with the ...........of the hose or pipe.

Answer 55

Length.

Question 56

****Second principle of FL: When hoses are the same size. friction loss varies approximately with the square of the increase in the velocity of the what? (Friction loss develops much faster then the change in velocity). PAGE # 147*****

Answer 56

Flow

Question 57

Third Principle of FL: For the same discharge, friction loss varies inversely as the fifth power of the diameter of the what? Ex: 2 1/2 hose to the 5th power, compared to 3 hose to the 5th power = 98/243 = 0.4 that of the 2 1/2 hose.

Answer 57

hose

Question 58

**Fourth Principle of FL: For a given flow velocity, friction loss is approximately the same, regardless of the .........on the water. (When the diameter of the hose doubles, the area of the hose opening increases approximately four times)

Answer 58

Pressure

Question 59

How much pressure is required to compresses water by 1%?

Answer 59

30,000 psi

Question 60

The smaller the hose, the greater the velocity needed to deliver the same what?

Answer 60

Volume

Question 61

By decreasing the amount of water flowing, a firefighter reduces the speed of the water in the hose; consequently, there is less what?

Answer 61

Friction loss.

Question 62

If velocity is increased beyond its limits, the friction loss becomes so great that the entire steam is agitated by resistance. This agitation causes a degree of turbulence called what?

Answer 62

Critical Velocity.

Question 63

What should be done if Critical Velocity is reached>

Answer 63

Parallel or Siamese hose lines to increase flow and reduce friction.

Question 64

Realistically, hose larger then what size can not be used for hand lines?

Answer 64

3"

Question 65

Apparatus inlets and remote outlets should be equipped with what to prevent damage from water hammer.

Answer 65

Pressure relief devices.

Question 66

What is used to protect high volume systems from water hammer?

Answer 66

Dump valves

Question 67

What should FD's ask the water utility to do when very large amounts of water are needed?

Answer 67

Increase the pressure.

Question 68

What are the four working parts of a water system?

Answer 68

Source of water supply. Means of moving water. Water processing or treatment facilities. Water distribution system, including storage.

Question 69

The amount of water a community needs can be determined by an engineering estimate. This estimate is the total amount of water needed for what?

Answer 69

Domestic and industrial use and for fire fighting use.

Question 70

What is the only way that a gravity system is sufficient?

Answer 70

If the source is several hundred feet above the highest use point.

Question 71

What type of water system do most cities use?

Answer 71

Combination systems

Question 72

Name four ways that water may have things removed from it.

Answer 72

Coagulation. Sedimentation. Filtration. The Addition of Chemicals, Bacteria, or other Organisms.

Question 73

The part of the water system that receives water from the pumping station and delivers it throughout the area served.

Answer 73

Water Distribution System

Question 74

The ability of a water system to deliver an adequate quantity of water relies upon what?

Answer 74

The carrying capacity of the systems network of pipes.

Question 75

List the three things a grid system consist of.

Answer 75

Primary Feeders. Secondary Feeders. Distributors.

Question 76

Convey large quantities of water to various points of the system for local distribution to smaller mains.

Answer 76

Primary Feeders

Question 77

Intermediate sized pipes that reinforce the grid. Aid the concentration of the required fire flow at any point.

Answer 77

Secondary Feeders

Question 78

Grid arrangement of smaller mains serving individual fire hydrants and blocks of consumers.

Answer 78

Distributors

Question 79

What should be done to ensure sufficient water to the high risk and industrial districts of the community.

Answer 79

Two or more primary feeders should run there on different routes.

Question 80

Secondary feeders should be arranged in what?, as far as possible to give two directions of supply to any point.

Answer 80

loops.

Question 81

Fire hydrant main size in residential areas?

Answer 81

6"

Question 82

Residential and business area recommended cross connection main size and spacing?

Answer 82

8" main. No more than 600' apart.

Question 83

Size of mains used on principle streets and in long mains not cross connected at frequent intervals?

Answer 83

12"

Question 84

Water mains as larger as what?, may be found in major cities.

Answer 84

48"

Question 85

How often should valves be operated to keep them in good condition?

Answer 85

Once a year

Question 86

Valves in private water systems are usually what kind?

Answer 86

Indicating

Question 87

What type of indicating valve is most commonly used in sprinkler systems?

Answer 87

OS&Y

Question 88

Non-indicating valves in water distribution systems are usually located in what?

Answer 88

Valve boxes or manholes.

Question 89

What is the most common type of valve used in most public water distribution systems?

Answer 89

Non-indicating

Question 90

What type of valves are control valves in distribution systems?

Answer 90

Butterfly or Gate. (Indicating or non indicating types)

Question 91

What should non rising stem gate valves be marked with?

Answer 91

A number indicating how many turns to close the valve.

Question 92

How many hydrants would have to be shut off to make a repair if the water system has the proper amount of valves installed?

Answer 92

One or two hydrants.

Question 93

What is pipe that is used under ground typically made of?

Answer 93

Cast Iron. Ductile Iron. Asbestos Cement. Steel. Plastic. Concrete.

Question 94

How can the effects of encrustation and sedimentation be reduced?

Answer 94

Flushing hydrants.

Question 95

The average of the total amount of water used in a water distribution system over the period of one year.

Answer 95

Average Daily Consumption (ADC)

Question 96

The maximum total amount of water that was used during any 24 hour interval within a 3 year period.

Answer 96

Maximum Daily Consumption (MDC)

Question 97

The maximum amount of water used in any 1 hour interval over the course of a day.

Answer 97

Peak Hourly Consumption (PHC)

Question 98

The maximum daily consumption is usually how many times more than the average daily consumption?

Answer 98

one to one and half times

Question 99

The peak hourly rate normally varies from ...........the normal hourly rate.

Answer 99

2-4 times

Question 100

Adequate water must be available at all times in the event a fire occurs. What should be strongly considered to ensure this need is meet?

Answer 100

The Maximum daily consumption and the Peak hourly consumption.

Question 101

Most commonly found on large commercial, industrial, or institutional properties.

Answer 101

Private Water Supply Systems

Question 102

List the three reason that a private water supply system may exist.

Answer 102

Strictly for fire protection. Water for sanitary and fire protection use. Water for fire protection and manufacturing use.

Question 103

Most commonly private water supply systems receive there water from where?

Answer 103

Municipal water supply systems.

Question 104

T of F Almost universally, private water supply systems maintain separate piping for fire protection and domestic/industrial services.

Answer 104

True

Question 105

When the diameter of a hose doubles, the area of the hose opening increases by how much?

Answer 105

Approximately four times. | Example: it would take four 11/2" hoses to reach the same flow as one 3" hose.