The microwave fire and the closed town-hall doors
At 13:05 the canteen microwave on the second floor of an IT office catches fire. Flames reach the exhaust hood and the floor fire panel goes into alarm. About 240 employees are on the floor. Thirty of them are in a town-hall meeting in the adjacent hall with the doors shut and the projector volume high. Six canteen staff are throwing a bucket of water on the microwave. Two workers are coughing and short of breath after inhaling smoke; a cook has a red, blistered forearm roughly the size of his palm. You are the on-duty security supervisor with two guards, one CO2 extinguisher at the canteen door and a dry-powder extinguisher in the lobby. The lift lobby is filling with people pressing the call buttons, and the staircases are at the two ends of the corridor.
1. Set out your first five actions in the first three minutes, in order, with the reason for each.
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The order is driven by life safety first, then containment, then property.
- Break the silence in the town hall. Send a guard to open those doors and shout the evacuation instruction inside, and cut the projector if the guard can reach it. Thirty people behind a closed door with a loud projector are the single most dangerous element here, because they will hear nothing until smoke reaches them.
- Stop the lifts and clear the lift lobby. Shout and physically direct people to the two staircases. A lift that stops on a smoke-filled floor becomes a trap, and the lobby is a choke point that will slow the whole evacuation.
- Call the fire brigade on 101 and the internal emergency number, giving floor, building, material burning (electrical appliance and duct), and casualties. Then sound the general evacuation and send the second guard to the assembly point to count.
- Stop the water. Two people throwing a bucket of water onto an energised microwave and a hood are risking electrocution and spreading burning material. Order them away from the appliance and, if the isolator is reachable, switch off the canteen circuit.
- Attack only if the fire is small and my exit is clear. Take the CO2 to the microwave with my back to the door. If the duct above the hood is alight, that is beyond a portable extinguisher: close the canteen door, withdraw, and let the fire service handle the duct.
2. Justify the extinguisher choice and the technique, and explain why the bucket of water was dangerous rather than merely ineffective.
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Choice. The fire started in an energised electrical appliance; in Indian classification, fires involving live electrical equipment are treated as a separate class (Class E in the older Indian scheme, and covered by the electrical guidance in IS 15683). CO2 is the correct medium: it is non-conducting, leaves no residue that would destroy the appliance, and works quickly in a confined space. Dry powder would also extinguish it and is the better choice for a large or spreading fire or for a Class B fat fire, but in a small kitchen it creates a blinding cloud that will hamper the evacuation and it contaminates food and equipment. Water and foam must never be used on energised equipment.
Technique. Pull, aim, squeeze, sweep: pull the pin, aim at the base of the fire, not at the flames or the hood, squeeze, sweep across the base. Stand one to two metres back, keep low under the smoke, keep my back to the escape route, and never let the fire get between me and the door.
Why the water was dangerous. Water conducts, so a stream onto a live microwave or socket can electrocute the person holding the bucket, and the guard would then have two casualties instead of one. Water on burning oil or fat in a canteen also causes violent steam expansion and a fireball. It was the right instinct - attacking the fire early - applied with the wrong agent.
3. Give the first aid for the two smoke-inhalation cases and the cook's burn, including what must not be done, and state when each casualty must go to hospital.
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Smoke inhalation (two workers). Move them to fresh air, away from the corridor, and sit them upright because lying flat worsens breathing. Loosen the collar, keep them calm, and monitor breathing and consciousness continuously. Give oxygen only if a trained first aider is present with a cylinder. Any hoarseness, soot around the nose or mouth, drowsiness, confusion or difficulty speaking means the airway is at risk and they must go to hospital by ambulance immediately, even if they now say they are fine - delayed swelling is the classic mistake. Be ready to start CPR at 30 compressions to 2 breaths, 100 to 120 per minute, if breathing stops.
Burn (cook's forearm, palm-sized, blistered). Cool it under gently running cool water for about twenty minutes, beginning as soon as possible; a blister the size of a palm is a partial-thickness burn. Remove a watch or ring before swelling starts. Cover with a clean, non-fluffy dressing or cling film laid flat, not wrapped tight. Do not apply ice, toothpaste, oil, turmeric or butter; do not burst blisters; do not peel away cloth stuck to the skin. Send him to hospital - a burn of that size on the forearm, and any burn on a hand, needs medical assessment and a tetanus check.
Record times, what was done and who did it for each casualty.