Safe Vehicle Stabilization Around High-Voltage Systems

Vehicle stabilization is one of the first tasks at a crash scene involving trapped occupants. In a conventional vehicle, responders apply cribbing, struts, jacks, and lifting equipment based on established stabilization principles and vehicle structure. In an electric or hybrid vehicle, those same placements may contact a traction battery pack, high-voltage cabling, or other energized components — creating electrical, thermal, and fire hazards that did not exist in the original incident.

This article addresses how high-voltage systems in BEVs, HEVs, and PHEVs affect stabilization decisions, and what responders need to know to stabilize these vehicles safely. It is intended to be read alongside Electric Vehicle Electrical Safety for First Responders, which covers broader EV operational response, and Recognizing High-Voltage Components in Electric Vehicles, which covers HV component locations and vehicle architecture in detail.

The Core Principle: Retrieve the ERG Before Stabilization Begins

The manufacturer Emergency Response Guide (ERG) or rescue sheet for the specific vehicle is the most reliable source of stabilization and lifting information for that vehicle. It identifies:

• Approved stabilization and lifting points
• Areas of the vehicle that must not support cribbing, jacks, or lifting equipment
• HV component and battery pack locations
• HV cable routing through the vehicle structure
• Rollover and side-resting guidance where provided
• Extrication cut zones and areas to avoid

NHTSA maintains a publicly accessible database of manufacturer ERGs and rescue sheets. Retrieving the correct document — by make, model, and year — should be an early incident command priority at any EV or hybrid vehicle crash. A rescue sheet for a similar model should not be substituted for the correct document; stabilization points, battery locations, and approved procedures differ between models and model years.

When the ERG is not immediately available, the safest default is to place stabilization equipment at obvious structural corners — the reinforced areas at the vehicle’s corners where the body structure meets the frame or rocker — and avoid the underbody center section until vehicle-specific information is obtained. This is a conservative operational principle, not a substitute for ERG-based guidance.

Traction Battery Locations and Why They Matter

The traction battery pack is the largest source of stored electrical energy in an EV or hybrid vehicle. Its location determines which areas of the vehicle structure present stabilization hazards — and which areas are safe for cribbing, jacking, and strut placement.

Battery location varies significantly by vehicle type and manufacturer:

• Underfloor (skateboard platform) — Many BEVs mount the battery pack beneath the passenger compartment floor, spanning a large portion of the underbody between the axles. This is common in vehicles such as the Tesla Model 3, Chevrolet Bolt, Hyundai IONIQ 5, and Ford F-150 Lightning, among others. In these vehicles, the underbody center section is occupied by the battery enclosure. Cribbing, jacks, or lifting equipment placed in this area without ERG guidance may contact the battery.
• Rear of vehicle — Some HEVs, including certain Toyota Prius generations, locate the traction battery under the rear cargo floor or behind the rear seat. The stabilization hazard profile is concentrated at the rear of the vehicle rather than the full underbody.
• Center tunnel — Some HEVs and PHEVs place battery components in the center tunnel or beneath the rear seat.
• Under-hood — Some HEVs locate battery components in the engine compartment.
• Distributed — Some vehicles distribute battery components across more than one location.

The battery location for the specific vehicle must be confirmed from the manufacturer ERG or rescue sheet. Do not assume the battery is under the floor, and do not assume that a configuration familiar from one vehicle applies to another.

For a detailed explanation of battery pack locations and HV component architecture across vehicle types, see Recognizing High-Voltage Components in Electric Vehicles.

Approved Stabilization and Lifting Points

Manufacturer ERGs and rescue sheets identify vehicle-specific approved stabilization and lifting points. These are reinforced structural areas designed to accept the loads associated with lifting and support — typically at or near the vehicle’s corners, at reinforced junctions between the body structure and the rocker or frame.

These approved points are not necessarily the same as conventional automotive jack points. A standard automotive jack point may be appropriate for tire changes under normal conditions but may not be the correct point for rescue stabilization under load. The ERG identifies the correct points for the specific vehicle.

Responders should not assume that any underbody location is an approved stabilization point without ERG confirmation. In underfloor-battery vehicles, the underbody center section between the axles is occupied by the battery enclosure — placing cribbing or jacks in this area may contact and damage the battery.

Multiple manufacturer ERGs — including those for Tesla, Chevrolet Bolt, Hyundai IONIQ 5, and Ford F-150 Lightning — consistently identify specific corner-area lifting points and explicitly warn against lifting or supporting the vehicle at other underbody locations.

Cribbing Placement

Cribbing placed at ERG-approved structural points provides stable support without contacting HV components. Cribbing placed in the underbody center section of an underfloor-battery vehicle may contact the battery enclosure.

Practical cribbing considerations for EV stabilization:

• Confirm battery location from the ERG before placing cribbing under the vehicle
• Place cribbing at approved structural points — typically at the vehicle’s corners at the rocker/frame junction
• Avoid the underbody center section of underfloor-battery vehicles unless the ERG confirms that specific area is safe
• Assess crash deformation — an approved cribbing point may be compromised by crash damage; assess whether the approved point remains structurally intact and away from battery damage before placing cribbing there
• Account for subsequent extrication — cribbing placement should not obstruct planned cut zones or extrication access areas identified in the rescue sheet

When the ERG is not immediately available, place cribbing at the vehicle’s structural corners and avoid the underbody center section until vehicle-specific information is obtained.

Stabilization Struts

Stabilization struts apply lateral or diagonal force to the vehicle to prevent rocking or rolling. In EV stabilization, strut placement requires awareness of HV cable routing through the rocker and sill areas, as well as battery enclosure location.

Key considerations:

• Rocker and sill areas may contain HV cables in some vehicles — the ERG identifies HV cable routing for the specific vehicle
• Strut foot placement on the ground and strut head contact with the vehicle should be at ERG-identified contact points where possible
• Tensioned systems that apply inward or upward pressure to the vehicle floor should be assessed against the battery enclosure location — pressure applied to the floor of an underfloor-battery vehicle may stress the battery enclosure
• Strut placement should not obstruct planned extrication access areas

The specific interaction between strut placement and HV cable routing is vehicle-dependent. The ERG is the reference for the specific vehicle.

Jacking and Lifting Equipment

Hydraulic jacks, air bags, and other lifting equipment used during stabilization or extrication must be placed at ERG-approved lifting points. Placement at non-approved underbody locations in an underfloor-battery vehicle may deform or penetrate the battery enclosure.

Consequences of battery enclosure damage from lifting equipment include HV electrical exposure, internal cell damage, thermal runaway, delayed fire, and toxic and flammable gas release — consistent with NHTSA and NTSB findings on physical battery damage.

Before placing any lifting equipment under an EV or hybrid vehicle:

• Confirm the approved lifting points from the ERG
• Identify the battery enclosure location relative to the planned lift point
• Assess whether crash deformation has moved the battery or compromised the approved lift point
• Do not improvise lift points in the underbody center section of an underfloor-battery vehicle

Vehicle Immobilization vs. HV Shutdown

These are two separate actions with separate purposes. Completing one does not accomplish the other.

Vehicle Immobilization

Vehicle immobilization prevents unintended vehicle movement. EVs and some HEVs operate silently or near-silently and may be in a ready state without audible indication. A vehicle that appears off may be capable of movement.

Immobilization steps typically include:

• Place the vehicle in Park
• Apply the parking brake
• Place wheel chocks at appropriate wheels
• Remove the key or key fob, or place it at a distance sufficient to prevent drive re-engagement (vehicle-specific — consult the ERG)

Immobilization addresses the movement hazard. It does not address the HV electrical hazard.

HV Shutdown and Isolation

Vehicle-specific HV shutdown or isolation procedures — where accessible and applicable — may reduce HV exposure in specific areas of the vehicle. The procedure varies by manufacturer and model and is identified in the ERG.

NHTSA is explicit that shutdown does not remove stored energy from the traction battery. NTSB SR-20-01 confirms that stranded energy remains in the battery after shutdown, fire, and other incidents. A service disconnect, where accessible, may interrupt the HV circuit between battery modules — but the battery cells themselves retain stored energy.

NTSB also found that crash damage or fire may make service disconnects inaccessible. Responders should not assume a disconnect procedure will be available or effective in a damaged vehicle.

After any shutdown or isolation procedure, responders should continue to treat the battery and HV components as energized and continue to avoid placing stabilization equipment against the battery enclosure.

Side-Resting and Rollover Vehicles

When an EV or hybrid vehicle is on its side or inverted, the stabilization hazard profile changes significantly.

In a vehicle with an underfloor battery that is resting on its side:

• The battery pack — normally protected by the vehicle floor — may be at or near the ground contact surface
• Stabilization equipment placed under the vehicle may directly contact the battery enclosure
• The vehicle’s normal stabilization contact areas are reoriented — the ERG’s component location diagrams must be mentally reoriented to match the vehicle’s actual position

Multiple manufacturer ERGs include specific guidance for side-resting and inverted vehicles, identifying which surfaces are appropriate for stabilization contact in those orientations. This guidance is vehicle-specific — no universal rollover stabilization procedure applies across all EVs.

When a vehicle is on its side or roof:

• Retrieve the ERG and identify the battery location relative to the vehicle’s current orientation
• Identify which surfaces are approved for stabilization contact in the rollover position
• Avoid placing stabilization equipment against surfaces that are adjacent to the battery enclosure in the vehicle’s current orientation
• Brief all personnel on the reoriented HV component locations before stabilization begins

When Battery Damage Is Suspected or Visible

Crash deformation in the battery area changes the stabilization picture in two ways: it may eliminate an approved stabilization point, and it elevates the risk of thermal runaway during and after stabilization and extrication operations.

When battery damage is suspected or visible:

• Assess whether approved stabilization points remain usable — crash deformation may have compromised the structural integrity of an approved point or moved it into proximity with battery damage
• Do not place stabilization equipment against a visibly damaged battery enclosure
• Monitor for warning signs throughout stabilization and extrication — smoke, unusual odors, hissing, popping, crackling, heat from the battery area, or fluid leakage
• Treat the vehicle as a potential thermal runaway hazard — the absence of immediate warning signs does not establish that the battery is undamaged

NHTSA notes that physical damage to the vehicle or HV battery may cause immediate or delayed toxic and flammable gas release and fire. A battery that shows no warning signs during stabilization may develop thermal runaway during or after extrication.

For a detailed explanation of thermal runaway, delayed fire development, and reignition risk, see EV Battery Fires and Thermal Runaway.

Extrication Interaction

Stabilization and extrication must be planned together, not sequentially without coordination. A stabilization system that is appropriate in isolation may create problems when extrication begins.

Key interaction points:

• Cut zones — the rescue sheet identifies recommended cut zones and areas to avoid. Stabilization equipment placed in a planned cut zone must be repositioned before cutting begins, which may destabilize the vehicle. Plan stabilization placement to avoid cut zones from the outset.
• Dash displacement — dash displacement operations apply force to the front structure. Stabilization must account for the forces involved and must not create pressure against the battery enclosure during the operation.
• Roof operations — roof removal changes the vehicle’s structural dynamics. Stabilization must remain effective through roof operations.
• Door removal and side access — strut placement should not obstruct door removal or side access areas identified in the rescue sheet.
• Lifting during extrication — if lifting is required during extrication, lifting points must be confirmed from the ERG and must not have been compromised by earlier stabilization equipment placement.

Incident command should ensure that stabilization and extrication personnel are working from the same ERG/rescue sheet information and that stabilization placement decisions account for the full extrication plan.

For PPE guidance relevant to working near damaged HV components during stabilization and extrication, see PPE for Electrical Emergencies.

Incident Command Considerations

Incident command is responsible for ensuring that stabilization operations at EV incidents are informed by vehicle-specific information:

• Assign ERG/rescue sheet retrieval as an early priority — before stabilization begins if possible
• Brief stabilization personnel on battery location, approved stabilization points, and areas to avoid before equipment is placed
• Coordinate stabilization and extrication planning — ensure both teams are working from the same vehicle-specific information
• Account for rollover orientation — brief personnel on reoriented HV component locations when the vehicle is on its side or roof
• Monitor for battery warning signs throughout stabilization and extrication operations
• Plan for delayed hazard development — a battery that appears undamaged during stabilization may develop thermal runaway during or after extrication
• Communicate HV hazard information to all incoming units and mutual aid

For broader electrical scene control principles applicable to EV incidents, see Electrical Hazards During Emergency Response and the Complete Guide to First Responder Electrical Safety.

What Responders Should Not Do

• Do not place cribbing, jacks, or lifting equipment in the underbody center section of an underfloor-battery vehicle without ERG confirmation that the area is safe.
• Do not assume that conventional automotive jack points are approved rescue stabilization points for EVs — confirm from the ERG.
• Do not place stabilization equipment against a visibly damaged battery enclosure.
• Do not assume that vehicle immobilization accomplishes HV isolation — they are separate actions.
• Do not assume that HV shutdown removes stored energy from the traction battery — it does not.
• Do not apply one vehicle’s approved stabilization points to a different make or model.
• Do not substitute a rescue sheet for a similar model when the correct document for the specific vehicle is available.
• Do not open, drill, penetrate, or dismantle the traction battery.
• Do not cut HV cables.
• Do not open HV junction boxes or enclosures.
• Do not treat 1000V-rated insulated hand tools as authorization for traction battery or HV component service.
• Do not improvise stabilization contact against battery enclosure areas when ERG guidance does not support it.

Dangerous Assumptions

Summary

Safe vehicle stabilization around high-voltage systems requires one foundational step before equipment is placed: retrieve the manufacturer ERG or rescue sheet for the specific vehicle and identify the approved stabilization and lifting points.

The key principles are:

• Battery location and HV cable routing vary by vehicle — no universal stabilization procedure applies
• Approved stabilization and lifting points are identified in the ERG — they are not necessarily the same as conventional automotive jack points
• Cribbing, jacks, and struts placed in the underbody center section of an underfloor-battery vehicle may contact the battery enclosure
• Vehicle immobilization and HV shutdown are separate actions — neither removes stored energy from the traction battery
• Rollover orientation changes the HV hazard profile — ERG diagrams must be reoriented to match the vehicle’s actual position
• Battery damage elevates thermal runaway risk throughout stabilization and extrication — monitor for warning signs and plan for delayed hazard development
• Stabilization and extrication must be planned together using the same vehicle-specific information

Related Resources

• Electric Vehicle Electrical Safety for First Responders
• Recognizing High-Voltage Components in Electric Vehicles
• EV Battery Fires and Thermal Runaway
• PPE for Electrical Emergencies
• Complete Guide to First Responder Electrical Safety
• First Responder Electrical Safety Resource Center