Fire Science

Question 1

What is Pyrolysis?

Answer 1

Thermal decomposition of a substance by heat.

Question 2

What happens that causes a fire to spread?

Answer 2

Objects reach Thermal capacity. (everything has a thermal capacity)
Gases are then given off
These gases then burn

Question 3

What is a passive?

Answer 3

Something that absorbs heat from a fire (everything is a passive agent)

Question 4

What are the types of gases?

Answer 4

Non flammable e.g. water vapour

Flammable gases e.g. carbon monoxide

Question 5

What are the limits of flamibility?

Answer 5

LEL - Lower explosive limit (anything below wont work)
UEL - Upper explosive limit (anything above wont work too rich)
IM - Ideal mixture

Question 6

Name 4 different ways that can cause differences in a fires development?

Answer 6

Position of room (middle 4, wall 2, corner 1)
Ceiling height
Ventilation
Smoke layer

Question 7

What are the 4 phases of a fire?

Answer 7

1. Early phase
2. Growth phase
3. Fully developed
4. Decay phase

Question 8

Name the 3 types of extinguishing methods?

Answer 8

Direct
Indirect
Gas cooling

Question 9

What is direct cooling?

Answer 9

Narrow jet aimed at base of fire used at the start of end of the fire.

Question 10

What is indirect cooling?

Answer 10

Defensive, can be used outside the building to cool the compartments or at the fire gases.

Question 11

What are the 3 gas cooling methods?

Answer 11

Short pulse - Above your head cool gas above BA team and protect routes
Long pulse - Fighting the fire back and absorb energy
Coning - Fighting the fire back and absorb energy

Question 12

What is the definition of combustion?

Answer 12

The chemical reaction in which fuel combines with heat and oxygen.