Electric Vehicle Underride with a Pinned Driver
At 22:15 a 2022 electric sedan rear-ended a flatbed trailer and is wedged 1.2 m under the trailer deck. The driver is conscious but confused and pinned by the dashboard. The high-voltage battery is under the floor; a faint sweet smell and a wisp of smoke come from the battery pack. The car's 12 V battery is in the trunk, which is crushed and inaccessible. The trailer carries 20 t of steel coils, and its rear wheels are off the ground. The car rests on a slight incline. Fire department resources include a pumper, hydraulic cutters, spreaders, rams, cribbing, and a thermal imager. The trailer frame is accessible. The incident commander must decide whether to extricate immediately or wait for a heavy wrecker 25 minutes out.
1. What stabilization is required before extrication, and what does the EV battery change?
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Stabilization comes before extrication. The trailer is unstable: 20 t of steel coils and rear wheels off the ground mean it can shift onto the car. Crib the trailer frame at multiple points with 6x6 cribbing, chock the car wheels, and prevent forward or backward movement before anyone works under the trailer. A heavy wrecker is 25 minutes out, so the incident commander must decide whether the cribbing is enough for a time-critical rescue. Do not crawl under an unsupported trailer.
The EV changes the plan because the battery is energized and may be in thermal runaway. Treat the car as live: do not cut orange cables, do not cut through the floor or battery case, and keep a charged hoseline ready. Use the thermal imager continuously. Establish an exclusion zone of at least 15 m and keep nonessential people out. The 12 V battery is inaccessible, so do not assume the vehicle is de-energized. A sweet smell and smoke mean battery involvement, not just a coolant leak.
2. The driver's door is jammed and the dashboard is trapping the legs. What extrication path and tool sequence?
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Start with glass management and access through the least damaged door. If the driver door is jammed, try the passenger side or rear door to reach the patient and assess the leg entrapment. Remove the driver door by cutting the hinges and latch if that creates space; avoid cutting the B-pillar or rocker area where high-voltage cables may run. Use a ram between the dash and the seat frame or door sill to displace the dash, with cribbing to hold each movement. Do not use a spreader in a way that pushes the dash into the patient.
The car is 1.2 m under the trailer, so roof removal may be impossible. Plan a dash displacement and seat slide. Keep the patient's spine aligned, protect the airway, and monitor for signs of crush injury. If battery smoke increases, the extrication plan changes: the patient must be moved faster or the crew must withdraw.
3. Battery smoke increases; the thermal imager shows 90°C at the pack and the driver is not yet free. What decision?
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This is a time-critical fire and rescue conflict. Smoke and 90°C at the pack suggest approaching thermal runaway, which can produce toxic and flammable gases and rapid fire spread. If the driver can be freed in about two minutes with the current plan, continue with a fire attack team standing by, SCBA for crews near the car, and a hoseline charged. If not, withdraw to at least 15 m upwind and switch to a defensive attack while keeping rescue options open.
The trigger for withdrawal is flame impingement or smoke filling the passenger compartment, not just a temperature reading. Do not send crews into a battery fire without water and SCBA. If the fire reaches the passenger compartment and the driver is still trapped, the incident commander must recognize that rescue is no longer viable and transition to recovery. That decision should be announced clearly and documented.