Structural Fire Fighting

Question 1

What can manipulating the fire triangle help FF’s do?

Answer 1

Effectively control and extinguish structural fire.

Question 2

What is Pyrolysis?

Answer 2

Pyrolysis is the decomposition of a substance caused by heat.

Question 3

What is Latent Heat Of Vaporisation?

Answer 3

The amount of heat required to change a given mass of substance from a liquid to a vapour.

Question 4

What is Heat Release Rate?

Answer 4

The amount of heat energy released over time.

Question 5

What is flashpoint?

Answer 5

Flash point is the lowest temperature at which a substance produces flammable vapour.

Question 6

What is fire point?

Answer 6

The lowest temperature at which a substance produces a vapour that can sustain a continuous flame. Usually a few degrees above the flash point.

Question 7

What is auto ignition temperature?

Answer 7

It is the temperature at which fuel will ignite on its own without any additional source of ignition.

Question 8

What is the flammability range?

Answer 8

The flammability range is the ratio of fuel to air.

Question 9

What is the neutral plane for structural firefighting purposes?

Answer 9

The area between the under pressure (fresh air) and the over pressure (hot fire gasses) in a compartment.

Question 10

Why does a gravity current occur?

Answer 10

Because fresh air is denser than the hot gases existing within the compartment.

Question 11

Explain Thorntons rule in simple terms.

Answer 11

As fire accesses more Oxygen, or as the oxygen increases, the heat release rate increases leading to potentially increased rates of extreme fire behaviour.

Question 12

Why is it important to understand Gas laws?

Answer 12

Can help a FF assess the stages of fire progression and intensity.

Question 13

Define a fuel controlled fire.

Answer 13

A fire that has more than enough air for combustion.

Question 14

Define a ventilation controlled fire.

Answer 14

A fire, where its growth is limited by the available air supply.

Question 15

What are the four phases of fire progression?

Answer 15

Developing fire
Flashover
Fully Developed
Decay

Question 16

What are the signs of flashover?

Answer 16

Ventilation controlled, vented fire
Painful radiant heat
Low turbulent neutral plane
Fingers of flame through smoke
Hot surfaces
Increased rate of pyrolysis
Increased turbulence of the neutral plane

Question 17

What are the signs of backdraught?

Answer 17

Ventilation controlled, non-vented fire
Lack of visible flame
Dirty smoke
Smoke pulsating
Air being drawn in
Indicators of extreme heat

Question 18

What is the difference between a fire gas explosion and a backdraught or flashover?

Answer 18

Fire gas explosion occurs in a seperate compartment from the fire room where’s the other two occur within the fire room itself.

Question 19

Signs of a Fuel Controlled Fire

Answer 19

Developing fire
High neutral plane
Better visibility
Bright yellow flame
Fire in decay stage

Question 20

Signs of a ventilation controlled fire

Answer 20

Fully developed fire
Low neutral plane
Poor visibility
Air being drawn back into fire
Smouldering fire
Smoke pulsating
Whistling sounds

Question 21

What is the purpose of direct attack?

Answer 21

To extinguish fire by direct surface cooling of the burning combustibles using a jet or spray.

Question 22

Purpose of an indirect attack.

Answer 22

Extinguish a fire by creating large amount of steam. Joint effect of gas and surface cooling and excluding oxygen from the compartment.

Question 23

What are gas cooling techniques used for?

Answer 23

To control the fire environment while FF’s advance during fire attack or perform search and rescue.

Question 24

What is the key to effective water use?

Answer 24

To place water where it is most needed, in hot fire gases and on burning combustibles

Question 25

When would you use an indirect attack?

Answer 25

When fire is fully involved or to suppress suspected backdraught

Question 26

What does Charles Law establish?

Answer 26

Gases expand when heated
Gases become less dense and rise when heated

Question 27

What does Gay-Lussac’s Law establish?

Answer 27

When gases are confined and heated, pressure increases.
Increased pressure indicates higher temperatures.