Fire Safety
What this domain tests
Fire behaviour, correct choice of extinguisher, and the exact sequence of action on discovering a fire.
The science
Fire needs fuel, heat, oxygen and an unbroken chain reaction - the fire tetrahedron. Remove any one and the fire dies.
Classes and matching extinguishers
- Class A - wood, paper, cloth: water or ABC dry powder.
- Class B - petrol, paint, solvent: foam, dry powder, CO2.
- Class C - LPG and other gases: dry powder after isolating supply.
- Class D - magnesium, sodium: special dry powder only.
- Class E (electrical) - CO2 or dry powder; never water.
- Class F/K - cooking oil: wet chemical.
PASS technique
Pull the pin, Aim at the base of the flame, Squeeze the handle, Sweep side to side, standing upwind and at a safe distance.
Emergency sequence - RACE
Rescue anyone in immediate danger, Alarm and call the fire brigade (101), Confine the fire by closing doors, Extinguish if trained and safe, otherwise Evacuate. Use stairs, never lifts, stay low under smoke, go to the assembly point, and let the fire warden complete the headcount.
Worked example
A guard sees smoke and sparks from an electrical distribution board. He does not throw water. He shouts the alarm, calls the control room, switches off the main supply if the panel is accessible and safe, uses a CO2 extinguisher on the board, clears people from the corridor and waits at the assembly point for the headcount. Reasoning: electricity plus water conducts current back to the user; isolating the supply removes the energy source and makes the fire manageable.
Traps that cost marks
- Using water on electrical or oil fires.
- Answering that lifts may be used for quick evacuation.
- Re-entering a building after evacuation to collect belongings.
- Extinguishers blocked by stock, or pressure gauge in the red zone.