Chapter 5

Question 1

The smallest particle of an element, which can exist alone or in combination.

Answer 1

Atom

Question 2

A deflagration (explosion) resulting from the sudden introduction of air into a confined space containing oxygen-deficient products of incomplete combustion.

Answer 2

Backdraft

Question 3

A hot, high-volume, high-velocity, turbulent, ultra-dense black smoke that indicates an impending flashover or autoignition.

Answer 3

Black fire

Question 4

The temperature at which the vapour pressure of a liquid equals the surrounding atmospheric pressure.

Answer 4

Boiling point

Question 5

An explosion that occurs when pressurized liquefied materials (e.g., propane or butane) inside a closed vessel are exposed to a source of high heat.

Answer 5

Boiling liquid/expanding vapor explosion (BLEVE)

Question 6

A colorless, odorless, electrically nonconductive inert gas that is a suitable medium for extinguishing Class B and Class C fires.

Answer 6

Carbon dioxide

Question 7

A toxic gas produced through incomplete combustion.

Answer 7

Carbon monoxide (CO)

Question 8

Energy that is created or released by the combination or decomposition of chemical compounds.

Answer 8

Chemical energy

Question 9

A fire in ordinary combustible materials, such as wood, cloth, paper, rubber, and many plastics.

Answer 9

Class A fire

Question 10

A fire in flammable liquids, combustible liquids, petroleum greases, tars, oils, oil-based paints, solvents, lacquers, alcohols, and flammable gases.

Answer 10

Class B fire

Question 11

A fire that involves energized electrical equipment.

Answer 11

Class C fire

Question 12

A fire in combustible metals, such as magnesium, titanium, zirconium, sodium, lithium, and potassium.

Answer 12

Class D fire

Question 13

A fire in a cooking appliance that involves combustible cooking media (vegetable or animal oils and fats).

Answer 13

Class K fire

Question 14

A space completely enclosed by walls and a ceiling. Each wall in the compartment is permitted to have openings to an adjoining space if the openings have a minimum lintel depth of 8 in. (200 mm) from the ceiling and total width of the openings in each wall does not exceed 8 ft (2.4 m). A single opening of 36 in. (900 mm) or less in width without a lintel is permitted when there are no other openings to adjoining spaces.

Answer 14

Compartment

Question 15

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.

Answer 15

Combustion

Question 15

Heat transfer to another body or within a body by direct contact.

Answer 15

Conduction

Question 16

The stage of fire development within a structure characterized by either a decrease in the fuel load or available oxygen to support combustion, resulting in lower temperatures and lower pressure in the fire area.

Answer 16

Decay stage

Question 16

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

Answer 16

Convection

Question 17

Heat that is produced by electricity.

Answer 17

Electrical energy

Question 18

Reactions that absorb heat or require heat to be added.

Answer 18

Endothermic

Question 19

The lowest temperature at which a liquid will ignite and achieve sustained burning when exposed to a test flame in accordance with ASTM 92

Answer 19

Fire point

Question 20

A geometric shape used to depict the four components required for a fire to occur: fuel, oxygen, heat, and chemical chain reactions.

Answer 20

Fire tetrahedron

Question 20

A rapid, persistent chemical reaction that releases both heat and light.

Answer 20

Fire

Question 20

Reactions that result in the release of energy in the form of heat.

Answer 20

Exothermic

Question 21

The range in concentration between the lower and upper flammable limits.

Answer 21

Flammable range (explosive limits)

Question 21

A geometric shape used to depict the three components of which a fire is composed: fuel, oxygen, and heat.

Answer 21

Fire triangle

Question 22

The minimum temperature at which a liquid or a solid emits vapor sufficient to form an ignitable mixture with air near the surface of the liquid or the solid.

Answer 22

Flash point

Question 23

A transition phase in the development of a compartment fire in which surfaces exposed to thermal radiation reach ignition temperature more or less simultaneously, and fire spreads rapidly throughout the space, resulting in full room involvement or total involvement of the compartment or enclosed space.

Answer 23

Flashover

Question 24

The movement of heat and smoke from the higher pressure within the fire area toward the lower pressure areas accessible via doors , window openings, and roof structures

Answer 24

Flow path

Question 25

A material that will maintain combustion under specified environmental conditions

Answer 25

Fuel

Question 26

A fire in which the heat release rate and fire growth are controlled by characteristics of the fuel because there is adequate oxygen available for combustion.

Answer 26

Fuel limited fire

Question 26

The stage of fire development where heat release rate has reached its peak within a compartment

Answer 26

Fully developed stage

Question 27

The physical state of a substance that has no shape or volume of its own and will expand to take the shape and volume of the container or enclosure it occupies

Answer 27

Gas

Question 28

The stage of fire development when the heat release rate from an incipient fire has increased to the point where heat transferred from the fire and the combustion products are pyrolyzing adjacent fuel sources and the fire begins to spread across the ceiling of the fire compartment (rollover)

Answer 28

Growth stage

Question 29

The measure of the rate of heat transfer to a surface, typically expressed in kilowatts per meter squared (kW/m2) or Btu/ft2)

Answer 29

Heat flux

Question 30

The rate at which heat energy is generated by burning

Answer 30

Heat release rate

Question 30

The movement of heat energy from a hotter medium to a cooler medium by conduction , convection, or radiation

Answer 30

Heat transfer

Question 31

An extremely toxic gas produced by the combustion of many common plastic-based materials. Low-level exposure can cause cyanosis, headache, dizziness, unsteady gait, and nausea.

Answer 31

Hydrogen cyanide

Question 32

The action of setting something on fire

Answer 32

ignition

Question 33

Minimum temperature a substance should attain in order to ignite under specific test conditions

Answer 33

ignition temperature

Question 34

The early stage of fire development where the fire's progression is limited to a fuel source and the thermal hazard is localized to the area of the burning material.

Answer 34

incipient stage

Question 35

A burning process in which the fuel is not completely consumed, usually due to a limited supply of oxygen.

Answer 35

incomplete combustion

Question 36

Smooth or streamlined movement of smoke, which indicates that the pressure in the building is not excessively high

Answer 36

Laminar smoke flow

Question 37

A fluid (such as water) that has no independent shape but has a definitive volume and does not expand indefinitely and that is only slightly compressible

Answer 37

Liquid

Question 38

The minimum concentration of a combustible vapor or combustible gas in a mixture of the vapor or gas and gaseous oxidant, above which propagation of flame will occur in contact with an ignition source

Answer 38

Lower explosive limit

Question 38

A form of potential energy that can generate heat through friction

Answer 38

Mechanical energy

Question 38

The interface at a vent, such as a doorway or a window opening , between the hot gas flowing out of a fire compartment and the cool air flowing into the compartment where the pressure difference between the interior and exterior is equal

Answer 38

Neutral plane

Question 39

Reaction with oxygen either in the form of the element or in the form of one of its compounds

Answer 39

Oxidation

Question 39

A chemical agent that causes severe pulmonary damage; it is a byproduct of incomplete combustion

Answer 39

Phosgene

Question 40

The column of hot gases, flames, and smoke rising above a fire; also called convection column, thermal updraft, or thermal column.

Answer 40

Plume

Question 40

A process in which material is decomposed, or broken down, into simpler molecular compounds by the effects of heat alone; it often precedes combustion

Answer 40

Pyrolysis

Question 41

The combined process of emission , transmission, and absorption of energy traveling by electromagnetic wave propagation between a region of higher temperature and a region of lower temperature

Answer 41

Radiation

Question 41

The condition in which unburned fuel (pyrolysate) from the originating fire has accumulated in the ceiling layer to a sufficient concentration that it ignites and burns. This can occur without ignition of, or prior to the ignition of, other fuels seperate from the origin; also known as flame over

Answer 41

Rollover

Question 42

The airborne solid and liquid particulates and gases evolved when a material undergoes pyrolysis or combustion, together with the quantity of air that is entrained or otherwise mixed into the mass

Answer 42

Smoke

Question 43

The attribute of smoke that reflects the stage of burning of a fire and the material that is burning in the fire.

Answer 43

Smoke colour

Question 44

The thickness of smoke. Because it has a high mass per unit volume, smoke is difficult to see through.

Answer 44

Smoke density

Question 45

A violent release of confined energy that occurs when a mixture of flammable gases and oxygen is present, usually in a void or other area seperate from the fire compartment, and comes in contact with a source of ignition. In this situation, there is no change to the ventilation profile , such as an open door or window; rather, it occurs from the travel of smoke within the structure to an ignition source

Answer 45

Smoke explosion

Question 45

The unburned , partially burned, and completely burned substances found in smoke

Answer 45

Smoke particles

Question 46

The speed of smoke leaving a burning building.

Answer 46

Smoke velocity

Question 47

The quantity of smoke, which indicates how much fuel is being heated.

Answer 47

Smoke volume

Question 48

One of the three stages of matter; a material that has three dimensions and is firm in substance.

Answer 48

Solid

Question 48

The physical state of a material-solid liquid gas

Answer 48

State of matter

Question 48

The degree of sensible heat as measured by a thermometer or similar instrument

Answer 48

Temperature

Question 48

A cylindrical area above a fire in which heated air and gases rise and travel upward.

Answer 48

Thermal column

Question 49

The stratification (heat layers) that occurs in a room as a result of a fire.

Answer 49

Thermal layering

Question 50

The means by which heat is transferred to other objects.

Answer 50

Termal radiation

Question 51

Agitated, boiling, angry-movement smoke, which indicates great heat in the burning building. It is a precursor to flashover.

Answer 51

Turbulent smoke flow

Question 51

The maximum amount of gaseous fuel that can be present in the air if the air/fuel mixture is to be flammable or explosive

Answer 51

Upper explosive limit

Question 52

The weight of an airborne concentration (vapor or gas) as compared to an equal volume of dry air.

Answer 52

Vapor density

Question 52

A fire in which the heat release rate and fire growth are regulated by the available oxygen within the space.

Answer 52

Ventilation limited fire

Question 53

The ability of a substance to produce combustible vapors

Answer 53

Volatility