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Flashcards in Fire Concepts and Behavior Deck (57):
1

What is the definition of fire?

The term used to describe the rapid oxidation of combustible materials accompanied by a release of energy in the form of heat and light

2

What is the definition of combustion?

The self-sustaining process of rapid oxidation of a fuel, being reduced by an oxidizing agent along with the evolution of heat, gases, vapors, soot, and light

3

What are the 3 components of fire? (Fire triangle)

Fuel
Heat
Oxygen

4

How much oxygen is in normal air?

21%

5

How much oxygen is required for free burning and visible flame?

16%

6

Does oxygen burn?

NO
It supports combustion

7

What are the 3 physical states of matter?

Solids
Liquids
Gases

8

What influences the ease of ignition and rate of burning?

Size and shape of fuel particles

9

What is heat?

Form of energy that raises temperature

10

What is temperature?

Measurement of heat intensity
Fahrenheit or Centigrade (Celsius)

11

What is BTU?

British thermal unit
Amount of heat required to raise the temperature of one pound of water one degree fahrenheit

12

What are the 4 sources of heat energy?

Mechanical
Electrical
Chemical
Nuclear

13

What are the 4 methods of heat transfer?

Convection
Conduction
Radiation
Direct flame contact

14

What are the 4 products of combustion?

Flame
Heat
Smoke
Fire gases

15

Know as many fire gases as you can

Carbon Monoxide
Formaldehyde
Hydrogen Cyanide
Hydrogen Chloride
Nitrogen Dioxide
Sulfur Dioxide
Nitrous Oxide
Phosgene

16

What are the 3 phases of fire?

Incipient
Free burning
Smoldering

17

For Incipient stage...
O2 level
Ceiling temperature

20-21%
Approx 100 degrees F

18

For free burning stage...
O2 level
Ceiling temperature

16-19%
Approx 1300 degrees F

19

For smoldering phase...
O2 level
Ceiling temperature

Less than 15%
Temperature throughout room approx 1000 degrees F

20

The main issue/concern of the incipient stage is the possibility of ____

Rollover

21

The main issue/concern of the free burning stage is the probability of ____

Flashover

22

The main issue/concern of the smoldering phase is the possibility of ____

Backdraft

23

Thermal balance is established during which phase?

Free burning stage

24

A room is totally filled with dense smoke and gases during which phase?

Smoldering

25

What are the 8 signs of backdraft?

Smoke under pressure
Black smoke becoming yellow gray
Confinement and excessive heat
Little or no visible flame
Smoke leaves room in puffs
Smoke stained glass
Muffled sounds
Sudden inrush of air when opening is made

26

The less oxygen content, the ____ the smoke

Darker

27

What are the 5 classes of fires?

A- Ordinary solid combustables
B- Flammable liquids, gases, and semisolids
C- Energized electrical equipment
D- Combustible metals
K- Cooking oils and fats

28

What are the 4 principles of fire control?

Heat control or cooling
Oxygen dilution or exclusion
Fuel removal or consumption
Chemical chain inhibition

29

What are 6 extinguishing agents?

CO2- Displaces oxygen
Dry chemical- Chain reaction inhibitor
Halon agent- Disrupts chain reaction
Foam- Fuel separation and chain reaction inhibitor
Dry powders- For class D fires
Water- Cools

30

What is rollover?

Hazard that occurs during incipient stage. Gasses are hot enough at ceiling to ignite and travel. May ignite fires behind you and cut off egress

31

What is flashover?

Hazard that occurs during free burning stage. All fuels in a room ignite spontaneously. Not survivable due to high temperatures

32

What is backdraft?

Hazard that occurs during smoldering stage. Sudden introduction of O2 into area that causes an explosion

33

What temperature is water when it's a liquid/solid/gas?

Solid- Below 32
Liquid- 32 to 212
Gas- above 212

34

What is the law specific heat?

Same as BTU

35

Water is affected by what 2 laws of physics?

Law of specific heat
Latent heat of vaporization

36

What is latent heat of vaporization?

Amount of heat required to change water from a liquid to a gas

37

Water expands ____ times when converted to steam

1700

38

____ ____ for efficient vaporization
____ ____ for penetration

Fog streams
Straight streams

39

What are the 3 types of fire attack?

Direct
Indirect
Combination

40

What is direct fire attack?

Close fog pattern is applied directly to the seat of fire in short bursts until the fire darkens down

41

What is considered a close fog pattern?

30 degrees or less

42

What stage is direct fire attack used?

Incipient stage

43

Why during direct fire attack do we use short bursts?

So we don't upset the thermal balance

44

What is indirect fire attack?

Use of latent heat of vaporization. Not desirable where victims may still be present.

45

What nozzle setting for indirect fire attack and where do you direct the stream?

30-60 degrees
Into the upper atmosphere

46

Indirect fire attack does not work without....

Super high temperatures and confined areas

47

What patterns are for combination fire attack?

T
S
O

Penetrating fog pattern

48

How should you move the stream with a combination fire attack?

Rotate clockwise with the stream edge touching the ceiling, floor, and walls

49

Define flash point

Temp at which liquid gives off sufficient vapor to flash but not continue to burn with an ignition source present

50

Define fire point

Temperature at which a liquid gives off sufficient vapor to flash and continue to sustain combustion with an ignition source present

51

Define ignition temperature/Auto ignition temperature

Temperature at which a material will self ignite without an ignition source present

52

Define flammable limits/range

Minimum and maximum concentrations of a gas in in air which will ignite

53

Define boiling point

The temp at which the pressure at the surface of a liquid becomes greater than atmospheric pressure

54

What is atmospheric pressure at sea level?

14.7psi

55

Define specific gravity

Molecular weight of a liquid compared to the molecular weight of water

56

Define vapor density

Molecular weight of a vapor compared to the molecular weight of air

57

Define solubility

Ability to mix with water or another liquid