Basement Fire Behind a Hot Closed Door with a Centered Open Stair
At 19:40 you respond to a 1,400-square-foot 1960s ranch with a finished basement. On arrival the front door is closed and smoke is pushing from the eaves and from a basement window on the B side. The occupant states everyone is out and the fire is "downstairs in the laundry." You stretch a 1¾-inch line to the front door. The thermal imager reads 380°F at the interior basement door, which is closed and hot to the touch. There is a single stair centered in the house with no door at the top. A second crew of two is on scene, and no one has vented anything. The basement has one casement window on the B side, 18 by 30 inches.
1. The basement door has not been opened. What must be true before anyone touches it, and what changes if you open it early?
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That door is currently the boundary holding a hot, fuel-rich upper layer in the basement. The house has a single centered open stair with no door at the top - it is a chimney waiting for a bottom opening.
Before the door moves, all of the following must be in place: a charged line at the door with the nozzle opened and bled, the nozzle firefighter masked up and positioned to the hinge side and below the neutral plane, a second firefighter controlling the door itself on a strap or with a tool, the stairwell and the floor above cleared of anyone not on the line, and the backup line or second crew staged at the top of the stairs.
Open it early and you complete a flow path from the fire through the basement door, up the open stair, and out through the eaves and any upper opening. The 380°F at the door becomes a bi-directional exchange into the hallway, and the stair becomes the exhaust. People get burned at the top of the stairs, not at the fire. Door control - opening it partway, staying behind it, keeping it between you and the fire - matters more than the stream for the first thirty seconds.
2. Do you attack down the interior stairs or from the B-side window? What are you trading away either way?
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Attack the fire compartment from the exterior window first, then go interior once the gas layer is knocked down.
The interior stair attack puts a crew directly in the flow path of an open-stair basement fire with a 380°F door and no ventilation - the highest-risk position in this building. The B-side casement gives you a straight shot at the ceiling of the fire room from outside, which cools the upper layer and cuts the energy feeding the stairwell. A straight or solid stream through that window will not push fire deeper in any meaningful way; the volume of water is a rounding error against the volume of the compartment.
The trade is real: an 18-by-30 casement admits only a small stream, the stream may break up on the sash, and you reach the ceiling gas layer far better than the seat of the fire. Expect to use water and expect only partial knockdown. Then take the interior stair with the line, door controlled, and finish. Do not skip the exterior hit to save water - the water is not the constraint; the stairwell is.
3. A firefighter on the second crew asks whether to vent the roof or open up at the top of the stairs. What is your answer and reasoning?
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No. Neither, not yet.
Vertical ventilation over a basement fire in a single-story ranch usually means opening the roof over the occupied floor - which does not vent the basement at all, and it does open the floor above the fire to the products of combustion. Opening at the top of the stairs is worse: with no door at the top of the stair, that opening is the exhaust side of a flow path that runs straight from the fire, up the open stair, and past anyone working on the first floor.
Ventilation here is sequenced, not simultaneous. The windows on the fire floor are the vents that matter, and they get taken from outside as part of the attack. Any opening at the top of the stairs happens after the line is in the basement and the fire is controlled, and it happens on the side opposite the attack and opposite the egress. Tell the second crew to stage a backup line and stand by for relief, and to keep the basement door controlled while the first line works.