Smoke on the Bridge with 41 Passengers
You are driving a 47-passenger coach across a 1,900-foot two-lane bridge over the Mississippi River at 9:15 p.m. with 41 passengers, including two using walkers and one using a wheelchair. Halfway across, a passenger shouts that smoke is coming from the rear of the bus. You see light gray smoke and smell hot plastic. The engine temperature gauge is normal, and no flame is visible. The bridge has no shoulder, a 4-foot sidewalk on the right behind a concrete barrier, and the nearest exit is about 700 feet ahead. Traffic behind you is light. Your extinguisher is mounted by the driver's seat and is rated 10 B:C. Dispatch has not answered your first radio call, and a passenger is already standing in the aisle.
1. What do you do in the next 30 to 60 seconds? Explain the factors you weigh.
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I would make a quick risk decision. Smoke in the passenger compartment is a potential fire, but the exit is only 700 feet ahead, roughly 15 to 20 seconds at 25 to 30 mph, and stopping on a bridge with no shoulder puts 41 people next to live traffic and delays responders. If the smoke stays light and I see no flame, I would keep moving to the end of the bridge, tell passengers over the PA to stay seated, and have a passenger call 911. If the smoke thickens, turns black, or I see flame, I would stop immediately, set the brake, shut off the engine, and evacuate. The key is not to freeze; either choice requires a clear announcement and an escape route. I would not open the engine cover while moving.
2. If you must stop on the bridge, how do you evacuate 41 passengers including walkers and a wheelchair?
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I would stop, set the parking brake, shut off the engine, take the keys, and turn on hazard lights. I would direct passengers out the right side onto the sidewalk behind the concrete barrier, away from traffic, then move them upwind and at least 100 feet from the bus, staying low under smoke. I would use the lift only if it is on the safe side and no fire is near it; otherwise two staff or passengers would assist the wheelchair user, and I would assign a companion to each walker. I would count 41 at the assembly point and report the count to 911 along with the bridge name, direction, and mile marker. I would not let anyone re-enter for belongings.
3. Would you use the 10 B:C extinguisher? Under what conditions?
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Only on a small, incipient fire with a clear escape path, and only after 911 is called and passengers are moving out. A 10 B:C rating means the extinguisher is for flammable liquids and electrical equipment, not ordinary combustibles, and it may discharge for only about 10 seconds. For an engine fire, I would not fully open the engine cover; I would discharge through the available opening and back away. If the fire is in the passenger compartment, the priority is evacuation, not extinguishment. I would never go back into a smoke-filled bus, and I would not fight a fire that is growing or between me and the exit.