Evfd Ifsta Essentials Of Fire Fighting 7 Ch 4

Front 1

The energy that a moving object possesses is known as:

Back 1

kinetic energy

Front 2

The type of chemical reaction in which a substance absorbs energy is an:

Back 2

endothermic reaction

Front 3

Which model includes the chemical chain reaction to explain the gas phase combustion of fire?

Back 3

fire tetrahedron

Front 4

Which type of ignition occurs without any external heat or flame igniting the fuel?

Back 4

Autoignition

Front 5

Smoldering charcoal is an example of __________ combustion.

Back 5

nonflaming

Front 6

When the air supply to a fire is limited, the level of incomplete combution is higher, which:

Back 6

produces more smoke

Front 7

Carbon monoxide acts as a chemical asphyxiant and commonly causes civilian fire fatalities as the products of __________ produced in a structure fire?

Back 7

combustion

Front 8

A toxic and flammable by product of combustion that is 35x more toxic than carbon monoxide is:

Back 8

hydrogen cyanide

Front 9

In a fire gases will always:

Back 9

move from areas of higher pressure to areas of lower pressure

Front 10

Which term describes the mearuse of energy flowing to an area or object?

Back 10

Heat flux

Front 11

Two surfaces rubbing together creates friction which generates:

Back 11

mechanical energey

Front 12

Which material is least able to conduct heat?

Back 12

AIR

Front 13

Which method of heat transfer occurs when energy is transferred by the circulation or movement of a liquid or gas?

Back 13

Convection

Front 14

When a fire transmits energy to an object some distance away from it thorugh electromagnetic waves, this is an example of:

Back 14

radiation

Front 15

An example of an inorganic fuel is:

Back 15

plastics

Front 16

For flaming combustion to occur, fuels must be:

Back 16

in the gaseous state

Front 17

In order to burn, liquid fuels must:

Back 17

vaporize

Front 18

The temperature at which a piloted ignition of sufficient vapors will begin a sustained combustion reaction is the:

Back 18

fire point

Front 19

The term that described the extent to which a fuel substance will mix with water is:

Back 19

solubility

Front 20

What is the term used to describe flammable liquids that will mix readily with water?

Back 20

polar solvents

Front 21

Pyrolysis occurs when a:

Back 21

solid fuel is heated suficiently so that it decomposes and gives off combustible vapors

Front 22

What is the primary consideration when determining how easily solid fuels ignite?

Back 22

surface to mass ratio of the fuel

Front 23

Air normally conssts of __________ % oxygen.

Back 23

21

Front 24

How would an atmosphere that has a low oxygen concentration of 15% affect combustion of materials?

Back 24

materials could still ignite and burn at regular temperatures

Front 25

Which is a true statement about fires in an oxygen-enriched atmosphere?

Back 25

materials that burn at normal oxygen levels will burn more intensely in an oxygen-enriched atmosphere

Front 26

What is the concentration limit above which the gas or vapor is said to be too rich to burn?

Back 26

Upper exlosive (flammable) limit (UEL)

Front 27

Flaming combustion is one example of a:

Back 27

chemical chain reaction

Front 28

What occurs when an extinguishing agent interfere with the chemical chain reaction and stops combustion?

Back 28

Chemical flame inhibition

Front 29

When sufficient oxygen is available for flaming combustion, a fire is said to be:

Back 29

fuel-limited

Front 30

In a ventilation-limited fire, the heat and growth is limited by the:

Back 30

amount of oxygen available to the fire

Front 31

Which stage of fire development occurs when the fire is small and confined to the fuel first ignited?

Back 31

incipient

Front 32

At the end of the growth stage, ventilation-limited fires tend to enter an early state of decay because there is no longer enough available __________ for the fire to become fully developed

Back 32

oxygen

Front 33

In the incipient stage of fire growth, the:

Back 33

compartment provides adequate oxygen and development depends on the fuel characteristics

Front 34

When a fire draws in air from around it, this is known as:

Back 34

entrainment

Front 35

The area surrounding a heat source in which there is sufficient air available to feed a fire is the __________ zone.

Back 35

combustion

Front 36

The tendency of gases to form into layers according to temperature, gas density, and pressure is thermal:

Back 36

layering

Front 37

The apperance of isolated or intermittent flames moving through the hot gas layer in a compartment can indicate that:

Back 37

flashover is about to occur

Front 38

The interface between the hot gas layer and cooler layer of air in a compartment fire is known as the:

Back 38

neutral plane

Front 39

While a closed compartment reduces the heat release rate of a fire, fuel may continue to pyrolize, which:

Back 39

creates fuel-rich smoke

Front 40

In ventilation limited fires any kind of ventilation will:

Back 40

increase the combustion rate

Front 41

As flashover occurs, the:

Back 41

combutible materials and gases in the compartment ignite almost simultaneously

Front 42

When unburned fire gases that have accumulated at the top of a compartment ignite and flames propagate through the hot gas layer or across the ceiling, this is called:

Back 42

rollover

Front 43

In order for a fire to progress to flashover, there must be sufficient heat relase rate and:

Back 43

ventilation

Front 44

What is an indicator that flashover is about to occur in a compartment fire?

Back 44

lowering of the neutral plane

Front 45

A ventilation limited compartment fire can produce a large volume of flammable smoke and other gases due to:

Back 45

incomplete combustion

Front 46

What can lead to backdraft?

Back 46

Ventilating a space filled with fuel-rich smoke

Front 47

Anytime a compartment or space contains hot combustion products, firefighters must consider the potential for backdraft before:

Back 47

creating any opening into the compartment

Front 48

The fully developed stage occurs when teh heat release rate of teh fire has:

Back 48

reached its peak

Front 49

The most effective method of increasing the heat release rate in a fuel limited, fully developed fire is to:

Back 49

provide more fuel

Front 50

Adding ventilation points to a compartment fire that is ventilation-limited will:

Back 50

add-oxygen that will allow the fire to grow

Front 51

It is __________ to make enough openings in a compartment to transition a fire from ventilation limited to fuel limited conditions

Back 51

not possible

Front 52

When a fire runs out of available fuel or oxygen, it is:

Back 52

in the decay stage

Front 53

The __________ in a structure fire consists of ambient air flow in and hot gases flowing out the exhaust.

Back 53

flow path

Front 54

Which factor affets a flow path's effectiveness to transport ambient air throughout the compartment?

Back 54

size of ventilation openings

Front 55

Which statement concerning flow path is true?

Back 55

when firefighters create openings for ventilation or to make entry, they establish new flow paths

Front 56

How can wind affect fire development in a structure fire?

Back 56

It can create pressure differences that cause windows to fail and provide oxygen to the fire

Front 57

A structure's fuel load is made up of:

Back 57

all combustible materials inside, including any flammable construction materials

Front 58

How is fire likely to react and spread within a structure?

Back 58

a fire burning within hidden cavities in the building can make it more difficult to find and can increase the potential for collapse

Front 59

Given enough available fuel, fire will follow oxygen through a building along any available __________.

Back 59

flow path

Front 60

Which feature of modern construction (homes built after 1990) poses problems for firefighters during extinguishment and ventilation?

Back 60

Synthetic interior finishes and light wood components

Front 61

How can lightweight or engineered trusses react under fire conditions?

Back 61

the trusses can fail without warning, even without flam contact

Front 62

Inoperative standpipes and sprinkler systems have become a contributing factor in fires in buildings __________.

Back 62

under demolition, renovation, or construction

Front 63

Asphyxiation

Back 63

fatal condition caused by seere oxygen deficiency and an excess of carbon monoxide and/or other gases in the blood

Front 64

Autoignition

Back 64

initiation of combustion by heat but without a spark or flame

Front 65

Autoignition Temperature (AIT)

Back 65

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

Front 66

Backdraft

Back 66

instantaneous explosion or rapid burning of superheated gases that occurs when oxygen is introduced into an oxygen-depleted confined space. The stalled combustion resumes with explosive force; may occur because of inadequate or improper ventilation procedures

Front 67

Buoyant

Back 67

The tendency or capacity of a liquid or gas to remain afloat or rise

Front 68

Carbon-Based Fuels

Back 68

Fuels in which the energy of combustion derives principally from carbon; includes materials such as wood, cotton, coal, or petroleum

Front 69

Carbon Dioxide (CO_2)

Back 69

Colorless, odorless, heavier than air gas that neither supports combustion nor burns, used in portable fire extinguishers as an extinguishing agent to extinguish Class B or C fires by smothering or displacing the oxygen

Front 70

Ceiling Jet

Back 70

Horizontal movement of a layer of hot gases and combustion by products from the center point of the plume, when a horizontal surface such as a ceiling redirects the vertical development of te rising plume

Front 71

Chemical Flame Inhibition

Back 71

extinguishment of a fire by interruption of the chemical chain reation

Front 72

Combustion

Back 72

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 flame

Front 73

Combustion Zone

Back 73

Area surrounding a heat source in which there is sufficient air availalbe to feed a fire

Front 74

Compartmentation

Back 74

the way that the arrangement of compartments creates or does not create a series of barriers designed to keep flames, smoke, and heat from spreading from one room or floor to another

Front 75

conduction

Back 75

physical flow or transfer of heat energy from one body to another, through direct contact or an intervening medium, from the point where the heat is produced to another location, or from a region of high temperature to a region of low temperature

Front 76

Convection

Back 76

transfer of heat by the movement of heated fluids or gases, usually in an upward direction

Front 77

Endothermic Reaction

Back 77

chemical reaction in which a substance absorbs heat

Front 78

Energy

Back 78

Capacity to perform work; occurs when a force is applied to an object over a distance, or when a substance undergoes a chemical, biological, or physical transformation

Front 79

Entrain

Back 79

to draw in and transport solid particles or gass by the flow of a fluid

Front 80

Exothermic Reaction

Back 80

chemical reaction between two or more materials that changes the materials and produces heat

Front 81

exposure fire

Back 81

a fire ignited in fuel packages or buildings that are remote from the initial fuel package or buildings of origin

Front 82

Fire

Back 82

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

Front 83

Fire Point

Back 83

Temperature at which a liquid fuel produces sufficient vapors to supportcombustion once the fuel ignites and is usually a few degrees above the flash point

Front 84

Fire Tetrahedron

Back 84

model of the four elemetns/conditions required to have a fire which represent fuel, heat, oxygen, and self-sustaining chemical chain reation

Front 85

Fire Triangle

Back 85

plane geometric model of an equilateral triangle that is used to explain the conditions/elements necessary for combustion the sides represent heat, oxygen, and fuel

Front 86

Flammable (Explosive) Range

Back 86

range between the upper flammable limit and lower flammable limit in which a substance can ignite

Front 87

Flash Point

Back 87

minimum temperature at which a liquid gives off enough vapors to form an ignitable mixturewith air near the surface of the liquid

Front 88

Flashover

Back 88

Rapid transition from the growth stage to the fully developed stage

Front 89

Flow Path

Back 89

the space between at least one intake and one exhaust outlet. The differene in pressure determines the direction of the flow of gases through this space. Heat and smoke in a high pressure area will flow toward areas of lower pressure

Front 90

Free Radical

Back 90

Electricially charged, highly reactive parts of molecues released during combustion reactions

Front 91

Fuel

Back 91

A material tat will mantain combustions under specified environmental conditions

Front 92

Fuel-limited

Back 92

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

Front 93

Fuel Load

Back 93

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

Front 94

Heat

Back 94

Form of energy associated with the motion of atoms or molecules within a fuel which is transferred from one body to another as a result of a temperature difference between the bodies, such as from the sun to the earth. To signifiy its intensity, it is measured in degrees of temperature

Front 95

Heat of Combustion

Back 95

total amount of thermal energy that could be gnerated by the combustion reaction if a fuel were completely burned. it is typically measured in kilojoules per gram (kJ/g) or megajoules per kilogram (Mj/kg)

Front 96

Heat Flux

Back 96

the measure of the rate of heat transfer to or from a surface, typically expressed in kilowatts per square meter (kW/m^2)

Front 97

Heat Release Rate

Back 97

Total amount of heat released per unit time and is typically measured in kilowatts (kW) or Megawatts (MW) of output

Front 98

Hydrocarbon Fuel

Back 98

petrolum based organic compound that contains only hydrogn and carbon; may also be used to describe those materials in a fuel load which were created using hydrocarbons such as plastics or synthetic fabrics

Front 99

Hydrogen Cyanide (HCN)

Back 99

Colorless, toxic, and flammable liquid until it reaches 79 degrees F and (26 degree C) Above that temperature it becomes a gas with a faint odor similar to bitter almonds, produced by the combustion of nitrogen bearing substances

Front 100

Incomplete Combustion

Back 100

Result of inefficient combustion of a fuel; the less efficient the combustion, the more products of combustion are produced rather than burned during the combustion process

Front 101

Isolated Flames

Back 101

Flames in the hot gas layer that indicate the gas layer is within its flammable range and has begun to ignite; often observed imediately before a flashover

Front 102

Joule (J)

Back 102

unit of work or energy in the International System of Units (SI); the energy (or work) when a unit force (1 newton) moves a body thorugh a unit distance (1 meter) ; defined in terms of mechanical energy.

In terms of thermal energy, these refer to teh amount of additional heat needed to raise the temperature of a substance

Front 103

Kinetic Energy

Back 103

Energy possessed by a moving objet because of its motion

Front 104

Lower Exposive (Flammable) Limit (LEL)

Back 104

lower limit at which a flammable gas or vapor will ignite and support combustion; below this limit the gas or vapor is too lean or thing to burn

Front 105

Matter

Back 105

Anything that occupies space and has mass

Front 106

Miscible

Back 106

materials tha are capable of being mixed in all proportions

Front 107

Neutral Plane

Back 107

Level at a compartment opening where there is an equal difference in pressure exerted by expansion and buoyancy of hot smoke flowing out of the openng and the inward pressure of cooler, ambent temperature air flowing in thorugh the opening

Front 108

Open Burning

Back 108

Description of a fire burning in the open with no restrictions to its oxygen supply

Front 109

Oxidation

Back 109

chemical process that occurs when a substance combines with an oxidizer such as oxygen in the air; a common example is the formation of rust on metal

Front 110

Oxidizer

Back 110

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

Front 111

Piloted Ignition

Back 111

moment when a mixture of fuel and oxygen encounters an external heat (ignition) source with sufficient heat or thermal energy to start the combustion reaction

Front 112

Polar Solvents

Back 112

Flammable liquids that have an attraction to water, much like a positive magnetic pole attracts a negative pole; examples include alcohols, esters, ketones, amines, and lacquers

Front 113

Potential Energy

Back 113

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

Front 114

Power

Back 114

Amount of energy deliered oer given period of time

Front 115

Pressure

Back 115

Force per unit area exerted by a liquid or gas measured in pounds per square inch (psi) or kilopascals (kPa)

Front 116

Products of Combustion

Back 116

Materials produced and released during burning

Front 117

Pyrolysis

Back 117

The chemical decomposition of a solid material by heating; precedes combustion of a solid fuel

Front 118

Radiation

Back 118

transmission or transfer of heat energy from one body to another body at a lower temperature through intervening space by electromagnetic waves

Front 119

Reducing Agent

Back 119

Fuel that is being oxidized or burned during combustion

Front 120

Rollover

Back 120

Condition in whichthe unburned fire gases that have accumulated at the top of a compartment ignite and flames propagate thorugh the hot gas layer or across the ceiling

Front 121

Self-Heating

Back 121

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

Front 122

smoke explosion

Back 122

form of fire gas ignition; the ignition of ccumulated flammable products of combustion and air that are within their flammable range

Front 123

Solubility

Back 123

degree to which a solid, liquid, or gas dissolves in a solvent

Front 124

Specific Gravity

Back 124

Mass (weight) of a substance compared to the weight of an equal volume of water at a given temperature

less than 1 indicates a substance lighter than water

greater than 1 indicates a substance heavier than water

Front 125

Spontaneous Ignition

Back 125

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

Front 126

Surface-To-Mass ratio

Back 126

ratio of the surface area of the fuel to the mass of the fuel

Front 127

Temperature

Back 127

Measure of the average kinetic energy of the particles in a sample of matter, expressed in terms of units or degrees designated on a standard scale

Front 128

Thermal Conductivity

Back 128

The propensity of a material to conduct heat within its volume. Measured in energy transfer over distance per degree of temperature

Front 129

Thermal Energy

Back 129

Kinetic energy associated with the random motions of the molecules of a material or object; often used interchangeably with the terms heat and heat energy

Front 130

Thermal Equilibrium

Back 130

The point at which two regions that are in thermal contact no longer transfer heat between them because the yhave reached the same temperature

Front 131

Thermal Layering

Back 131

Outcome of combustion in a confined space in which gases tend to form into layers according to temperature, gas density, and pressure with teh hottest gases found at the ceiling and the coolest gases at floor level

Front 132

Upper Explosive (Flammable) Limit (UEL)

Back 132

Upper limit at which a flammable gas or vapor will ignite above this limit the gas or vapor is too rich to burn

Front 133

Vapor Density

Back 133

Weight of pure vapor or gas compared to the weight of an equal volume of dry air at the same temperature and pressure

less than 1 indicates a vapor lighter than air

greater than 1 indicates a vapor heavier than air

Front 134

Vapor Pressure

Back 134

The pressure at which a vapor is in equilibrium with its liquid phase at a given temperature; liquids that have a greater tendency to evaporate have higher vapor pressures at a given temperature

Front 135

Vaporization

Back 135

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

Front 136

Ventilation-Limited

Back 136

Fire with limited ventilation in which the heat release rate or growht is limited by the amount of oxygen available to the fire

Front 137

Watt (W)

Back 137

The SI unit of power or rate of work equal to 1 joule per second (J/s)