Electrical Smoke on a Barrier-Separated Highway
You are driving a 48-passenger bus with 36 students on a six-lane divided highway posted 55 mph. The concrete median barrier is on your left; the right shoulder is narrow, with a guardrail beyond it. Smoke is coming from under the dashboard, and you smell electrical burning; no flames are visible. You are 0.8 mile from an interchange with a wide shoulder and an exit. Traffic is heavy. Two students use wheelchairs and are secured in the front; the other 34 students are ambulatory. The temperature is 90°F. Your fire extinguisher is mounted behind the driver’s seat. The smoke begins to increase, and the bus has not lost power. You have a radio and cell phone; dispatch answers on the second call.
1. Should you stop immediately or try to reach the interchange? What factors drive the decision?
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The increasing smoke changes the calculation. A small, stable odor might justify continuing a short distance to a safer interchange, but increasing smoke from under the dashboard suggests an electrical fire that can spread or cause loss of control. At 55 mph, 0.8 mile takes about 52 seconds, and that may be too long with students aboard. Stop as soon as you can get the bus fully off the travel lane; if the narrow shoulder is not wide enough, stop in the right lane with hazard lights on and evacuate away from traffic. Do not open the hood or dash if smoke is heavy. Keep the engine off after stopping if the bus is safely positioned. If flames appear, stop immediately and evacuate without trying to reach the exit.
2. If you evacuate on the highway, where do you place the students and how do you handle the two wheelchair users?
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Evacuate away from traffic and, if possible, behind the guardrail or upwind of the smoke. Do not gather students in front of or behind the bus where traffic or fire can reach them. Assign two calm students as buddies to help move ambulatory students, but keep the group together. For the wheelchair users, deploy the lift only if it can be done away from traffic and without delaying the evacuation of students in immediate smoke. If the lift cannot be used safely, use the trained buddy-carry or emergency-exit procedure for wheelchair users, and remove them from the smoke as quickly as possible. Do not let anyone reboard for belongings. Count all 36 students against the roster at the assembly point and report missing or injured students to responders.
3. What communication and post-evacuation actions are required?
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Call 911 first if fire or smoke is increasing, then radio dispatch with the location, direction of travel, number of students, and whether anyone is injured. Ask for fire and EMS and tell dispatch that two students use wheelchairs. Keep the students at the assembly point, upwind and away from traffic, and do not let them wander back toward the bus. Meet responders and give them the roster count and the last known location of any student. Do not restart or move the bus. After the emergency, document the smoke, the evacuation route, the time of the stop, the 911 call, and the student accounting. Notify the school and transportation supervisor, and do not return the bus to service until the electrical cause is repaired and inspected.