L2 March 24 fire and fire protection

Question 1

State the four elements of the fire tetrahedron. (4 marks)

Answer 1

Oxygen
Heat
Fuel
Chemical chain reaction

Question 2

One of the factors evaluated through fire resistance testing for systems and products used in
a building is insulation. Identify and describe two other factors. (4 marks)

Answer 2

Stability
The ability of the buildings structure to resist the effects of heat from a fire without significant loss of stability/load bearing capacity giving time for evacuation. examples are Sacraficial timber or Steel protection… thin film intumescent etc.

Insulation, the ability to resist excessive heat transfer from one compartment to another preventing combustion by radiant heat. 140degree average or 180degree at any one point.

Integrity, the ability of a wall or floor to resist the effects of fire without gaps opening that allows the passage of flames and smoke to pass to another compartment

Question 3

In relation to the principles of means of escape in case of fire, explain what is meant by:
a) Occupancy (2 marks)
b) Construction (2 marks)

Answer 3

a) Occupancy
Occupancy refers to how a building or space is used and the number and type of people who occupy it. This includes:

The function of the building (e.g., residential, commercial, educational, industrial).

The number of occupants expected in the building at any given time.

The mobility and awareness of occupants (e.g., children in a school, patients in a hospital, workers in an office, or residents in a care home).

Why it’s important:
The type and number of people affect escape time and behavior in emergencies.

Buildings with high occupancy or vulnerable occupants (like hospitals or schools) require wider, more direct, and more numerous escape routes.

Occupancy informs decisions like travel distances, exit widths, and the need for fire alarms, lighting, and signage.

b) Construction
Construction refers to the design, materials, and structural features of the building that affect its fire safety, particularly in relation to how a fire might spread and how well escape routes are protected. This includes:

The fire resistance of walls, floors, and ceilings.

The use of non-combustible or fire-rated materials.

Presence of compartmentation (i.e., dividing a building into fire-resistant sections).

The location and protection of staircases, corridors, and fire doors.

Why it’s important:
Good construction ensures escape routes remain usable and safe for longer during a fire.

It limits smoke and flame spread, helping to protect escape paths.

It influences the overall fire strategy, including whether alternative escape routes are needed.

In summary:

Occupancy determines who needs to escape and how many, affecting the design of escape routes.

Construction determines how well the building can protect those routes during a fire, ensuring people can actually use them to escape safely.

Question 4

State four locations within a building that would normally be covered by emergency escape
lighting. (4 marks)

Answer 4

 At each exit door
 On escape routes
 At intersection of corridors
 Outside each final exit and on external escape routes
 At the location of emergency escape signs
 On stairways so that each flight receives adequate light
 Changes in floor level
 Windowless rooms and toilet accommodation exceeding 8m²
 At the location of fire-fighting equipment
 At the location of fire alarm call points
 At the location of equipment that would need to be shut down in an emergency
 In lifts
 In areas in premises greater than 60m2