Chapter 5 Fire Behavior Flashcards

1
Q

Physical science is the study of …… and …… and includes chemistry and physics.

A

matter and energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Anything that occupies space and has mass.

A

Matter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What type of change occurs when a substance changes in size, shape or appearance, but the chemically stays the same?

A

Physical Change Ex: Water freezing, Water boiling

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What type of change occurs when a substance changes from one type of matter to another?

A

Chemical change

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

When two or more substances combine they form a?

A

Compound

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

A chemical reaction involving the combination of a oxidizer, with another material.

A

Oxidation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

The capacity to perform work.

A

Energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Stored energy possessed by an object that can be released in the future to to perform work once released.

A

Potential Energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

The energy possessed by a body because of its motion.

A

Kinetic Energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

List seven types of energy.

A

chemical, thermal, electrical, mechanical, light, nuclear, sound

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Can all energy change from one type to another?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

In terms of a fire, the potential chemical energy of a fuel is converted to thermal energy and released as?

A

Heat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Name the measure of energy in the International System of Units (SI) and also for the customary system.

A

SI = Joules (J) Customary = Btu

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How many joules does it take to change the temperature of one gram of water by one degree Celsius?

A

4.2 joules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

The amount of heat required to raise the temperature of 1 pound of water 1 degree Fahrenheit.

A

Btu

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How many joules = 1 Btu?

A

1055J

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Reactions that emit energy are called?

A

Exothermic ex: fire

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Reactions that absorb energy are called?

A

Endothermic ex: converting water to steam.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

A chemical process of oxidation that occurs at a rate fast enough to produce heat and usually light in the form of either a glow or a flame?

A

Combustion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

A rapid oxidation process, which is a chemical reaction resulting in the evolution of light and heat in varying intensities?

A

Fire

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

A form of energy characterized by vibration of molecules and capable of initiating and supporting chemical changes and change of state.

A

Heat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Measure of a materials ability to transfer heat energy to other objects.

A

Temperature.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

A material that will maintain combustion under specific environmental conditions.

A

Fuel

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Any material that readily yields oxygen or other oxidizing gas, or that readily reacts to promote or initiate combustion of combustible materials.

A

Oxidizer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Name two forms of ignition.

A

Piloted and auto (nonpiloted)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

The most common type of ignition. Occurs when a mixture of fuel and oxygen encounter an external heat source with sufficient heat or thermal energy to start the combustion process.

A

Piloted Iginition

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Occurs with out any external flame or spark to ignite the fuel gases and vapors.

A

Auto Ignition

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

The auto ignition temperature of a substance is always higher then its …………

A

Piloted ignition temperature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

The chemical decomposition of a solid material by heating. Often precedes combustion.

A

Pyrolysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Physical process that changes a liquid into a gaseous state; the rate depends on the substance involved, heat, pressure, and exposed surface area.

A

Vaporization

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

The process of initiating self sustained combustion.

A

Ignition

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Pyrolysis occurs in what type of fuel

A

solids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Vaporization occurs in what type of fuel?

A

Liquids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

The lowest temperature at which a combustible material ignites in air without a spark or a flame.

A

Autoignition Temprature (AIT)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

True or False Combustion is a chemical reaction while fire is possible result of combustion.

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Name two modes of combustion.

A

Flaming and nonflaming

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Occurs slowly, lower temps, produces a smoldering glow.

A

Nonflamming combustion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Produces a visible flame above the materials surface.

A

Flaming combustion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Name the two models that are used to describe the element of fire and how to extinguish it.

A

Fire Triangle, Fire Tetrahedron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Materials that absorb heat but do not participate actively in the combustion process. Given a example.

A

Passive Agents. ex: Gypsum/Humidity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Smoke is a product of incomplete combustion. It is a aerosol comprised of what?

A

gases, vapor, and solid particulates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Materials produced and released during burning.

A

Products of combustion.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

A toxic and flammable product of incomplete combustion of organic materials. The most common product of combustion encountered in structure fires. Chemical asphyxiant that binds with hemoglobin preventing O2 from binding with it.

A

Carbon Monoxide (CO)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Toxic, flammable, produced in the combustion of materials containing nitrogen. Chemical asphyxiant that prevents the body from using O2 at the cellular level.

A

Hydrogen Cyanide (HCN)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Product of complete combustion of organic material, acts as a simple asphyxiant by displacing O2, also stimulates respiratory system causing increase in resp rate,

A

Carbon Dioxide (CO2)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Substances that cause breathing discomfort. Inflammation of the eyes, resp tract, and skin.

A

Irritants

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

How many irritants have test shown are in smoke? Give three examples.

A
  1. hydrogen chloride, formaldehyde, acrolein
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

True or False. Flame is also considered to be a product of combustion?

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

The kinetic energy associated with the random motions of the molecules of a material or object.

A

Thermal Energy. aka: heat and heat energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

the measurement of heat.

A

Temperature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

Equation. Celsius to Fahrenheit

A

F = (C x 1.8) + 32

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

Equation: Fahrenheit to Celsius

A

C = (F -32) / 1.8

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

Name six sources of thermal energy.

A

Chemical, Mechanical, Electrical, Light, Nuclear, Sound

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

The most common source of heat energy in combustion.

A

Chemical

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

The result of exothermic reactions, occurring spontaneously in some materials under certain conditions, whereby heat is generated at a rate sufficient to raise the temperature of the material.

A

Self-Heating

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

Initiation of combustion of a material by an internal chemical or biological reaction that has produced sufficient heat to ignite the material.

A

Spontaneous Ignition

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

Name three things that must happen for spontaneous ignition to take place.

A

heat can not dissipate faster then it is produced, materials temp must reach its auto ignition temp, available air must be able to support combustion.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

Name four ways that electrical heating can occur.

A

Resistance, Overcurrent / overload, Arcing, Sparking

59
Q

Type of energy generated by friction or compression.

A

Mechanical Energy

60
Q

True or false. Some appliance are designed to make use of resistance heating?

A

True

61
Q

What is unintended resistance heating?

A

Overload or Overcurrent

62
Q

What is a high temp luminous discharge across a gap or through a medium?

A

Arc

63
Q

What is the spatter that make be produced from a arc?

A

Spark

64
Q

True or false? Heat is transferred from warmer to cooler objects. Materials at the same temp can not transfer heat?

A

True

65
Q

The measure of the rate of heat transfer to a surface, expressed as kilowatts per meter squared (KW/m2)

A

heat flux

66
Q

Name three ways heat con be transferred.

A

Conduction, Convection, Radiation.

67
Q

Transfer of heat through or between solids that are in direct contact.

A

Conduction

68
Q

Heat transfer by circulation within a medium such as gas or liquid.

A

Convection

69
Q

Heat transfer by way of electromagnetic energy.

A

Radiation

70
Q

What is believed to be the weakest part of a PPE ensemble.

A

SCBA facepiece.

71
Q

Name three factors that effect radiant heat transfer.

A

Nature of the exposed surface, Distance, Temp difference between the source and the exposed surface.

72
Q

As the temperature of the heat source increases, the radiant energy increases by a factor of?

A

Four

73
Q

Can hot smoke in the upper layers radiate heat?

A

Yes

74
Q

The fuel that is being oxidized or burned during combustion.

A

Reducing Agent

75
Q

Total amount of thermal energy that could be generated by the combustion reaction if a fuel were completely burned.

A

Heat of combustion

76
Q

Total amount of heat released per unit of time.

A

Heat release rate

77
Q

The rate at which energy is being transferred over time.

A

Power

78
Q

A unit of measure of power or rate of work equal to one joule per second.

A

Watt

79
Q

Heat release rate is dependent on what three things?

A

type, quantity, and orientation of the fuel.

80
Q

T or F? Gaseous fuels are already in their physical state required for ignition?

A

True

81
Q

Weight of a given volume of pure vapor or gas compared to the weight of an equal volume of dry air at the same temp and pressure. Less then 1 = rise. Greater then 1 = sink.

A

Vapor Density

82
Q

Mass of a substance compared to the mass of an equal volume of water at a given temp. Less then 1 = float Greater then 1 = sink.

A

Specific Density

83
Q

What is the vapor pressure of air at sea level?

A

14.7 psi

84
Q

Measure of the tendency of a substance to evaporate.

A

Vapor Pressure. Liquids with a higher tendency to evaporate will have a higher vapor pressure.

85
Q

Any liquid having a flash point below 100 F and a vapor pressure not above 40 psi absolute.

A

Flammable liquid

86
Q

The ease with which a liquid gives off vapor.

A

Volatility

87
Q

The minimum temperature at which a liquid gives off sufficient vapor to ignite, but not sustain combustion.

A

Flash Point

88
Q

The temperature at which sufficient vapors are being generated to sustain combustion.

A

Fire point. Must exceed 5 seconds of burning duration.

89
Q

A increase in surface area decreases the extent at which a liquid will give off vapor. T or F?

A

False

90
Q

The degree to which a solid, liquid, or gas will mix / dissolve with water.

A

Solubilty

91
Q

Materials that will mix with water in any proportion

A

Misicible

92
Q

A liquid with a attraction to water.

A

Polar Solvents

93
Q

Liquid having a flash point at or above 100 f and below 200 f.

A

Combustible Liquid.

94
Q

Chemical decomposition of a material through the action of heat.

A

Pyrolysis.

95
Q

Matter with a definite shape and size?

A

Solid

96
Q

Surface to mass ratio. As the ratio increases the fuel particles become smaller. T or F?

A

True

97
Q

Proximity and orientation of a solid fuel affect the way it burns. T or F?

A

True

98
Q

Oxidizers are not combustible but will support and enhance combustion. T or F?

A

True

99
Q

At normal ambient temps (68F) materials can ignite and burn at O2 levels as low as?

A

14%

100
Q

Percentage of O2 that equals a deficient atmosphere and the percent that equals a enriched atmosphere.

A

<23.5%

101
Q

Can variations in temp and pressure cause the flammable range of a gas or vapor to be vary?

A

Yes

102
Q

The range between the LFL and UFL in which a substance can ignite.

A

Flammable (Explosive) range

103
Q

Upper limit at which a gas or vapor will ignite. Above the limit the vapor is to rich to burn.

A

Upper Flammable Limit (UFL)

104
Q

Lower limit at which a gas or vapor will ignite and support combustion. Below the limit the fuel is said to be to lean to burn.

A

Lower Flammable Limit (LFL)

105
Q

Molecular fragments that are highly reactive.

A

Free Radicals

106
Q

Because of the release of free radicals during the combustion of methane, the production of CO and formaldehyde could be formed. T or F?

A

True

107
Q

Extinguishment of a fire by interruption of the chemical chain reaction

A

Chemical chain Inhibition.

108
Q

List the four stages of fire development.

A

Incipient, Growth, Fully Developed, Decay

109
Q

List seven things that influence fire development within a compartment.

A

Fuel Type, Availably and location of additional fuels, Compartment volume and ceiling height, Ventilation, Thermal properties of the compartment, Ambient Conditions, Fuel Load.

110
Q

List four factors that influence the availability and location of additional fuels.

A

Building Configuration, Construction Materials, Contents, Proximity of the initial fire to expose fuel sources.

111
Q

A fire in a larger compartment will develop more slowly then one in a small compartment. T or F? Why?

A

True. Radiant heat has to travel farther to heat a larger area. Will maintain longer due to increased air source.

112
Q

Name the two forms that room or compartment fires take.

A

Fuel or Ventilation controlled.

113
Q

A fire with adequate oxygen in which the heat release rate and growth rate are determined by the characteristics of the fuel, such as quantity and geometry.

A

Fuel Controlled

114
Q

A fire with limited ventilation in which the heat release rate or growth is limited by the amount of oxygen available to the fire.

A

Ventilation Controlled

115
Q

The total quantity of combustible contents of a building, space, or fire area, including interior finishes and trim, expressed in heat units of the equivalent weight of wood.

A

Fuel Load

116
Q

Stage of fire that starts with the ignition of a fuel. Typically a fuel controlled fire. Radiant heat begins to warm additional fuels. Hot gas begins to mix with cooler air in the room. Temps in the room are not much above ambient temps.

A

Incipient Stage

117
Q

Stage of fire where the location of the fire in the room effects the amount of air entrained and thus the amount of cooling that is taking place. A higher plume is more rapidly increasing the temps at the upper level of the room. Heat is radiated back to the fire by surfaces in the room.

A

Growth Stage

118
Q

Tendency of gases to form into layers according to temp.

A

Thermal Layering. aka: heat stratification, thermal balance.

119
Q

The area where the pressure of hot gas exiting a room and cooler gas exiting a room are equal.

A

Thermal Plane

120
Q

Rapid transition from growth to fully developed?

A

Flashover

121
Q

Typically flash over occurs in what stage of fire?

A

Growth. May occur in the fully developed stage.

122
Q

Most fires that grow beyond the incipient stage will become ventilation or fuel controlled?

A

Ventilation controlled

123
Q

Stage of fire where all combustible materials in a compartment are burning, burning fuels are releasing the max amount of heat possible, large volumes of fire gas, ventilation controlled, fire may extent to other compartments.

A

Fully Developed Stage

124
Q

Stage of fire where all fuel is consumed or where o2 levels are to low to sustain combustion.

A

Decay Stage

125
Q

In a limited ventilation decay fire the temp may decrease but what is still taking place?

A

Pyrolysis

126
Q

Name three types of rapid fire development.

A

Flashover, Backdraft, Smoke Explosion

127
Q

Flash over occurs when the environment changes from two layers to one untenable layer. T or F?

A

True

128
Q

List four common elements of flashover.

A

Transition in fire development, Rapidity, Compartment, Ignition of all exposed surfaces.

129
Q

Flashover typically occurs at what temp?

A

1100F

130
Q

List smoke indicators of flashover.

A

rapidly increasing volume, turbulence, darkening color, optical density, lowering of the hot gad layer.

131
Q

List a heat indicator of flash over.

A

darkening windows

132
Q

List a flame indicator of flashover.

A

Isolated flames in the hot gas layer or at the ceiling.

133
Q

A increase in low level ventilation before upper level ventilation can result in what?

A

Back draft

134
Q

List smoke indicators of potential back draft.

A

Optically dense smoke, light colored or black becoming dense gray-yellow. neutral plane rising and lowering (breathing movement).

135
Q

List heat indicators of potential back draft.

A

high heat, smoke stained windows.

136
Q

List a flame indicator of potential back draft.

A

little or no visible flame.

137
Q

Will a back draft always occur after a opening has been made into the compartment?

A

No, it may take some time for the proper air to fuel mixture to occur.

138
Q

This may occur before or after the decay stage. If smoke that is within its flammable range finds a ignition source this may happen.

A

Smoke Explosion

139
Q

List five ways that firefighters influence fire behavior.

A

Temp reduction, Fuel removal, O2 exclusion, Chemical Flame inhibition, Ventilation and fire behavior.

140
Q

Cooling with water cannot sufficiently reduce vapor production to extinguish fires involving low flash point flammable liquids and gases. T or F?

A

True

141
Q

When water is converted to steam at 212 F it expands by how many times?

A

1700

142
Q

Chemical flame inhibition is effective on gas and liquid fuels because they must flame to burn. T or F?

A

True. They are ineffective to non flaming fires.

143
Q

The planned, systematic, and coordinated introduction of air and removal of hot gases and smoke from a building.

A

Tactical Ventilation

144
Q

Give a example of unplanned ventilation.

A

Wind, doors being left open.