Restaurant Basement Fire with Pulsing Smoke
At 22:05 you are the first-arriving captain at a two-storey restaurant with a basement. Smoke is pushing from floor vents, the front door, and a side cellar entrance; the front windows are dark but stained, and smoke pulses from a vent in short bursts. All customers are out, but a dishwasher is unaccounted for. The basement is used for dry storage and has a concrete floor at street level, a wood-joist ceiling, and a single metal cellar door at grade that is hot to the touch. A thermal imager shows high heat at the top of the cellar door. Two pumpers, one ladder, and ten firefighters are on scene. The restaurant has no sprinklers and only one interior stair to the basement. Smoke is beginning to bank down in the ground-floor dining room.
1. Identify the fire behaviour indicators and decide whether to open the cellar door. Explain the sequence and safeguards you would use.
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The pulsing smoke, dark stained windows, heat at the cellar door, and short smoke bursts are classic backdraft indicators: a fuel-rich, oxygen-deficient basement with an ignition source and limited openings. Opening the cellar door as a casual ventilation move could produce a rapid ignition and kill anyone in the door front. The first action is to charge a 45 mm line and position a crew at the door with SCBA and a coordinated opening plan. All personnel not essential to the opening must be clear of the door front and side. Open the door remotely or from behind a wall if possible, then cool the upper layer with a brief exterior stream before entry. Simultaneously, a primary search of the ground floor should proceed from a protected entrance, but not into the basement until the atmosphere is controlled. The missing dishwasher is a life-safety priority, but an uncontrolled door opening could kill the search crew and any survivors. Ventilation must be coordinated with attack; opening the front and cellar without a charged line in place creates a flow path that can pull fire into the dining room.
2. How would you organize search and rescue given the missing dishwasher and the single basement stair?
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The search plan should be phased and tied to fire control. First, search the ground floor from a protected entrance with a charged line at the front door, because that is where occupants would most likely have exited. Second, prepare a basement entry only after the cellar door has been controlled and cooled and a backup line is in place. If the basement is a single open storage area, two crews can enter with a thermal imager and a guide rope; if it is compartmented, search must be methodical and slow. Do not let the missing-person report push an uncoordinated basement entry; that is how rescuers become casualties. With ten firefighters, establish a rapid intervention team outside before basement entry, and assign a safety officer to watch the cellar door and the ground-floor collapse indicators. The ladder crew can open upper windows only after the attack line is charged and the incident commander confirms that ventilation supports the attack rather than drawing fire through the building. The rescue is complete only when the basement has been searched and the atmosphere is stable enough to verify the result.
3. Ten minutes after opening the cellar door, the pulsing stops and smoke turns black and heavy. What does this change in your plan?
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The change from pulsing to steady black smoke suggests the basement has become ventilation-controlled in a different way or that the fire has grown and is now communicating with the opening. It does not mean the hazard is over. The incident commander should reassess the flow path, heat conditions, and structural stability of the wood-joist ceiling. If the cellar opening is now feeding the fire and the ground-floor dining room is banking smoke, crews must either control the opening or withdraw to a defensive posture. Benchmarks for withdrawal include worsening smoke conditions in the dining room, audible or visible structural movement, water runoff turning from dark to clear? No, water runoff alone is not a reliable sign. More reliable triggers are a sudden increase in heat, smoke pushing from new cracks, or crews reporting deteriorating visibility. The incident commander should confirm a personnel accountability report before any change in strategy, keep the backup line in place, and not commit additional crews to the basement until the fire behaviour is understood. Communication to crews should be direct: state the change, the new objective, and the withdrawal route.