School Canteen: LPG Cylinder Fire With Students Present
At 10:15, during a school assembly with 40 students on the ground, a 14.2 kg LPG cylinder in the canteen develops a flame at the valve. The canteen is 12 m from the assembly line. An electric distribution board on the same wall is sparking. A teacher has a 4.5 kg CO2 extinguisher and a 6 kg ABC dry powder extinguisher. A sand bucket is 20 m away, and a peon wants to use the garden hose on the fire. The cylinder has been burning for about four minutes, and the metal near the valve is too hot to touch. The fire brigade has been called but is eight minutes away.
1. State the first three actions in order and explain why evacuation outranks firefighting here.
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- Evacuate and account for students. The assembly is only 12 m away, and a cylinder failure can throw flame and metal fragments well beyond that. Move students upwind to a pre-agreed assembly point at least 50 m away, keep class-wise headcounts, and prevent children from running back for bags.
- Call and confirm the fire brigade, then isolate the area. Give the exact location, cylinder involvement, and the sparking distribution board. Keep a clear access route for the fire tender and stop traffic through the lane.
- Only then consider controlled firefighting by trained staff. A burning LPG cylinder is not a routine wastebasket fire; untrained intervention can turn a leak into an explosion.
The reasoning is that the students are the irreplaceable risk. Firefighting is a property-protection action with a narrow window and a high chance of sudden escalation. The teacher with extinguishers should fight only from a protected position with an escape route behind, never alone, and never with students nearby. The peon's garden hose should not be used on the energised distribution board.
2. Which extinguishing medium should be used on the cylinder and the electrical board, and why?
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Electrical distribution board: use CO2 first. It is non-conductive, leaves no residue and is suitable for energised electrical equipment. Switch off the supply if the main switch is safe to reach. Never use water or foam on a live board.
LPG cylinder flame at the valve: use ABC dry powder on surrounding fires and to knock down flame if a trained person can approach from the side with the wind behind them. The critical rule is: do not extinguish the gas flame unless the gas supply can be shut off. A burning flame is consuming the leaking gas; if it is put out while gas continues to escape, an explosive gas-air cloud can form and find the sparking board.
Cooling: water can be used as a cooling spray on the cylinder from behind cover, but not as a direct jet on a live electrical board and not by an untrained person standing in the open. The metal near the valve is too hot to touch, so nobody should try to close the valve bare-handed.
Sand is useful for small spills and absorbent smothering, not for a pressurised gas fire. The correct judgement is to cool, isolate, and let trained responders shut off or remove the cylinder.
3. The fire brigade will take eight minutes. What should staff do in that window, and what should they not do?
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Do:
- Keep the assembly point stable, take a second headcount, and assign one teacher to each class.
- Clear a 15 m cordon around the canteen and move any vehicles or gas cylinders away if safe.
- Station a responsible adult at the gate to guide the fire tender and report the cylinder and live board.
- If a trained staff member uses the CO2 on the board, do it with a colleague present and a clear retreat.
- Check for anyone missing without sending children into the building.
Do not:
- Do not let the peon spray water on the electrical board or on burning oil.
- Do not try to drag a hot cylinder out of the canteen; a heated cylinder can rupture.
- Do not reopen the canteen or send students back for bags.
- Do not stand in front of the cylinder or in the doorway.
The reasoning is that the eight-minute gap is long enough for a cylinder to fail. The aim is to reduce exposure and preserve a clear approach, not to win a firefight with two small extinguishers.