Compartment Firefighting

Question 1

Water application techniques can be grouped under three main headings which are

Answer 1

Indirect

Direct

Gas cooling

Question 2

Indirect water application technique is..

Answer 2

When water is directed from outside the compartment into the flammable gases and onto the compartment boundaries

Question 3

What are the purposes of indirect water application technique

(2)

Answer 3

To suppress or extinguish a fire by producing large quantities of steam

Can be used for backdraught suppression

Question 4

Indirect branch settings are..

Answer 4

Medium spray aimed above and around the fire

Branch must be moved around to ensure maximum coverage

Question 5

The effects of indirect are…

4

Answer 5

Cools and diluted the fire gases

Cools the structure of the compartment

The large quantities of steam produced smother the fire

Lowers the neutral plane, reducing vision and worsening conditions for firefighters and casualties

Question 6

Direct water application technique is..

Answer 6

When water is applied directly in the seat of the fire.

It can be applied on a fully ventilated fire, a fire in its early stages (before neutral plane has developed) or when the fire gases are under control

Question 7

Purpose of direct water application

Answer 7

To extinguish the fire

Question 8

Branch settings for direct water application?

Answer 8

Solid jet or narrow spray aimed directly at the fire

Question 9

Effects of direct water application

4

Answer 9

Extinguishes fire

Potential for excessive water damage

Air can be entrained into the compartment and fire, intensifying the reaction when initially applied

In a compartment with limited ventilation where an over pressure has developed, it has the potential to lower the neutral plan and worsen conditions for firefighters and casualties

Question 10

Why is gas cooling used?

Answer 10

Is used to control the environmental conditions with a fire compartment.

Increases the safety and effectiveness of firefighting teams; reducing likelihood of backdraught, flashover and fire gas explosions

Question 11

Two different pulsing techniques?

Answer 11

Long pulse

Short pulse

Question 12

Short pulse purpose?

Answer 12

To provide a safe zone, cooling the gases in the immediate vicinity of the firefighting team

Question 13

Short pulse branch settings

Answer 13

Medium to wide spray, depending on the height of the ceiling

Using very short pulses

Aimed directly above firefighters into the over pressure

Question 14

Effect of short pulse

Answer 14

Cools and diluted the flammable gases

Question 15

Long pulse purpose?

Answer 15

The extinguish flaming combustion in the gas layer and allow firefighters to advance through the compartment

Question 16

Long pulse branch settings

Answer 16

Medium spray

Using longer pulses, depending on penetration required

Aimed directly into the over pressure, ahead of firefighters, at the ignited fire gases

Question 17

Long pulse effect?

Answer 17

Cools and diluted the flaming combustion

Question 18

What is the purpose of painting?

Answer 18

To suppress pyrolysis and extinguish the fire

Question 19

Branch settings of painting

Answer 19

Small trickles of water

Using the least amount of water possible, depending on penetration required

Aimed directly into all combustion substances and materials

Question 20

Effect of painting?

Answer 20

To cool all combustible materials and substances, preventing decomposition which causes fire gases to be produced (pyrolysis)