Fire Concepts and Behavior

Question 1

What is the definition of fire?

Answer 1

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

Question 2

What is the definition of combustion?

Answer 2

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

Question 3

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

Answer 3

Fuel
Heat
Oxygen

Question 4

How much oxygen is in normal air?

Answer 4

21%

Question 5

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

Answer 5

16%

Question 6

Does oxygen burn?

Answer 6

NO

It supports combustion

Question 7

What are the 3 physical states of matter?

Answer 7

Solids
Liquids
Gases

Question 8

What influences the ease of ignition and rate of burning?

Answer 8

Size and shape of fuel particles

Question 9

What is heat?

Answer 9

Form of energy that raises temperature

Question 10

What is temperature?

Answer 10

Measurement of heat intensity

Fahrenheit or Centigrade (Celsius)

Question 11

What is BTU?

Answer 11

British thermal unit

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

Question 12

What are the 4 sources of heat energy?

Answer 12

Mechanical
Electrical
Chemical
Nuclear

Question 13

What are the 4 methods of heat transfer?

Answer 13

Convection
Conduction
Radiation
Direct flame contact

Question 14

What are the 4 products of combustion?

Answer 14

Flame
Heat
Smoke
Fire gases

Question 15

Know as many fire gases as you can

Answer 15

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

Question 16

What are the 3 phases of fire?

Answer 16

Incipient
Free burning
Smoldering

Question 17

For Incipient stage…
O2 level
Ceiling temperature

Answer 17

20-21%

Approx 100 degrees F

Question 18

For free burning stage…
O2 level
Ceiling temperature

Answer 18

16-19%

Approx 1300 degrees F

Question 19

For smoldering phase…
O2 level
Ceiling temperature

Answer 19

Less than 15%

Temperature throughout room approx 1000 degrees F

Question 20

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

Answer 20

Rollover

Question 21

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

Answer 21

Flashover

Question 22

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

Answer 22

Backdraft

Question 23

Thermal balance is established during which phase?

Answer 23

Free burning stage

Question 24

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

Answer 24

Smoldering

Question 25

What are the 8 signs of backdraft?

Answer 25

``` 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 ```

Question 26

The less oxygen content, the ____ the smoke

Answer 26

Darker

Question 27

What are the 5 classes of fires?

Answer 27

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

Question 28

What are the 4 principles of fire control?

Answer 28

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

Question 29

What are 6 extinguishing agents?

Answer 29

``` 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 ```

Question 30

What is rollover?

Answer 30

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

Question 31

What is flashover?

Answer 31

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

Question 32

What is backdraft?

Answer 32

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

Question 33

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

Answer 33

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

Question 34

What is the law specific heat?

Answer 34

Same as BTU

Question 35

Water is affected by what 2 laws of physics?

Answer 35

Law of specific heat | Latent heat of vaporization

Question 36

What is latent heat of vaporization?

Answer 36

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

Question 37

Water expands ____ times when converted to steam

Answer 37

1700

Question 38

____ ____ for efficient vaporization | ____ ____ for penetration

Answer 38

Fog streams | Straight streams

Question 39

What are the 3 types of fire attack?

Answer 39

Direct Indirect Combination

Question 40

What is direct fire attack?

Answer 40

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

Question 41

What is considered a close fog pattern?

Answer 41

30 degrees or less

Question 42

What stage is direct fire attack used?

Answer 42

Incipient stage

Question 43

Why during direct fire attack do we use short bursts?

Answer 43

So we don't upset the thermal balance

Question 44

What is indirect fire attack?

Answer 44

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

Question 45

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

Answer 45

30-60 degrees | Into the upper atmosphere

Question 46

Indirect fire attack does not work without....

Answer 46

Super high temperatures and confined areas

Question 47

What patterns are for combination fire attack?

Answer 47

T S O Penetrating fog pattern

Question 48

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

Answer 48

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

Question 49

Define flash point

Answer 49

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

Question 50

Define fire point

Answer 50

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

Question 51

Define ignition temperature/Auto ignition temperature

Answer 51

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

Question 52

Define flammable limits/range

Answer 52

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

Question 53

Define boiling point

Answer 53

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

Question 54

What is atmospheric pressure at sea level?

Answer 54

14.7psi

Question 55

Define specific gravity

Answer 55

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

Question 56

Define vapor density

Answer 56

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

Question 57

Define solubility

Answer 57

Ability to mix with water or another liquid