Wheel-Well Smoke on a Loaded Motorcoach
At 2:15 p.m. on a 90°F day, you are driving a 47-passenger motorcoach northbound on I-95 near Bangor with 41 passengers aboard. You are in the center lane. In the right mirror you see gray smoke coming from the right rear wheel well, and you smell burning rubber. Traffic is heavy at 65 mph. The right shoulder is about 8 feet wide next to a guardrail. Aboard are a wheelchair user in the middle of the coach, two passengers using canes, and one passenger using a portable oxygen concentrator. Your fire extinguisher is a 10 BC dry chemical unit mounted by the driver's seat. The rear emergency door is clear; the aisle has two bags in it. The next exit is 1.5 miles ahead.
1. What are your first actions, and where do the passengers go?
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Stop now. Signal, move as far onto the 8-foot shoulder as the guardrail allows, stop smoothly, set the parking brake, shift to park, turn on hazard flashers, shut off the engine, and get everyone off. Smoke at a rear wheel well can be a brake, wheel-bearing, or tire fire, and it can spread to the fuel tank or battery. Use the front door and, if needed, the rear door, and move passengers at least 100 feet away, upwind, and behind the guardrail-not along the shoulder or in the traffic lane. Call 911 with the mile marker, direction, vehicle description, and 41 passengers. Count heads against the seat count. Do not open a wheel well or get under the bus.
2. How do you handle the wheelchair user, the oxygen user, and the cane users?
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Move the wheelchair user and the oxygen user first, but not through or toward the smoke. If the fire is at the right rear and the front door and lift are clear, lower the lift only if it can be done without trapping the chair; a lift cycle is slow, so assign two or three people to assist a carry if the smoke is worsening. Keep the oxygen concentrator upwind and away from the fire-oxygen makes a fire burn hotter. Assign helpers to the two cane users. Move the two aisle bags only if they block the exit; otherwise step around them. Recheck that the rear door is fully open and the exit path is clear.
3. When do you use the extinguisher, and when do you not reboard?
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Use the 10 BC extinguisher only if the fire is small, you can stay between the fire and the passengers, and you have a clear escape path behind you. Aim at the base of the fire. A BC rating is for flammable liquids and electrical equipment; a tire or brake fire also involves Class A material, so the dry chemical may knock it down but not cool it. If there is heavy smoke, flames near the fuel tank, or the fire is already under the bus, do not fight it-keep everyone back and let the fire department handle it. Never reboard until the fire department says it is safe. A burned bus is replaceable; 41 people are not.