Smoke in the Rear Wheel Well
You are driving a 40-foot coach with 38 passengers on an interstate at 65 mph. It is 15:00, dry, and traffic is heavy. A passenger shouts that smoke is coming from the right rear wheel well. You smell burning rubber and see a puff of black smoke in the right mirror. The coach is approaching a concrete median barrier with a narrow right shoulder; the next exit is 1 mile ahead. The coach has a 2.5-pound ABC dry-chemical extinguisher by the driver and another in the rear. Passengers are standing in the aisle to look. A tractor-trailer is close behind, and the engine is still running. You have not seen flames, but the smoke is getting thicker.
1. What are your immediate actions in the first 60 seconds?
Read the worked answer
I would signal right, slow smoothly, and stop on the shoulder as far from the travel lane as I can, without crossing the median barrier. I would set the parking brake, shut off the engine, turn on flashers, and tell passengers in a calm, loud voice to exit through the front door and move away from the coach and traffic. I would not let them stand in the aisle to look. I would direct them at least 100 feet away, upwind and behind the barrier if possible, and then call 911. I would account for passengers by seat count or a quick head count. The smoke may be a tire or brake fire, but I would treat it as a possible vehicle fire until proven otherwise.
2. Should you use the 2.5-pound extinguisher? What factors decide that?
Read the worked answer
I would use the extinguisher only if the fire is small, I can see the base of the fire, I have a clear exit behind me, and I have been trained to use it. A 2.5-pound ABC extinguisher is small; it may knock down a small tire or brake fire but will not cool a hot wheel or stop a fuel fire for long. I would approach from upwind, keep my back to an escape path, and aim at the base of the flames. I would not fully open a wheel well or engine compartment if doing so would feed air to the fire. If there are flames, heavy smoke, or any question about the fuel system, I would leave it to the fire department and keep passengers away.
3. After everyone is off the coach, what do you do before the bus is moved or returned to service?
Read the worked answer
I would keep passengers together, check for injuries or smoke inhalation, and call 911 if not already done. I would put out warning devices only if it is safe, and I would not move the coach until the fire department says it is safe. I would preserve the scene and report the incident to my company. The coach would not return to service until a qualified mechanic inspected the wheel bearing, brake, tire, and any damaged components. I would document the passenger count, the evacuation, the extinguisher use, and the dispatcher notifications. If the fire department finds evidence of a mechanical defect, I would make sure the carrier knows before the vehicle is dispatched again.