Rotterdam Fire District 6 - Hybrid Extrication

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Rotterdam Fire District 6 - Hybrid Vehicle Extrication Information

The information below is informational only. It does not replace departmental SOGs. The Response Guides below have very good information on cut zones and areas to avoid during an extrication.

Generic Rescue Tasks Common to All Vehicles

There are three basic tasks associated with all motor vehicles and departments should consider including them when updating or developing SOPs/SOGs for vehicle rescue:

Immobilize the Vehicle: Prevent the vehicle from moving under power by by gravity. Chock/block the wheels, shift into PARK if not already done, shut the vehicle OFF and remove the key/keyless FOB to a point greater than (15) feet from the vehicle's dash. Many conventional and hybrid vehicles use a keyless entry/start ignition/start system.
Stabilize the Vehicle: If extrication is required, stabilizing the vehicle is NOT an option. The vehicle's weight is transferred from suspension system to the frame that is resting on cribbing or other suitable equipment designed for stabilization.
Disable the Vehicle Once the vehicle's has been used to the responder's advantage (power down windows, open locks, move seats, etc), the responder then disconnects the battery terminal cables (negative first then positive) or cut a 3-4 inch section out of the low voltage cables. DO NOT attempt to disconnect the high voltage battery cables. Hybrid vehicles can run silent and in this state may provide power to the low voltage system. If the IGNITION SYSTEM can not be SHUT OFF, the responder will need to access the specific recommendation of that MAKE and MODEL hybrid vehicle. NEVER touch, cut, push, or breach any ORANGE high voltage cable or other high voltage component. Doing so may result in serious burns or death.

Responder Safety: Shut Down/OFF the Ignition System

A primary objective for the emergency responder at a hybrid incident will be to shut the vehicle OFF, this provides the following:

Shuts down the hybrid system
Shuts down the fuel pump
Stops electrical flow to the SRS ECU
Isolates the high voltage current from the HV battery pack

NOTE: It should be noted that the hybrid system will have high voltage capacitors that can store a high voltage current for up to 10 minutes, even after the vehicle is shut down/off. Always consider a high voltage cable to be live/hot. Always use the vehicles power to your advantage prior to disabling, such as, but not limited to: Powering down windows, open locks/latches, move electric seats.

Low Voltage vs. High Voltage

There are conventional vehicles that have already converted to the 42V DC electrical system. The onboard computers systems are taxing the 12V systems, which can no longer keep up. The industry as a whole will soon switching from the 12V electrical system to the 42V. While the Society of Automotive Engineers considers this to be low voltage, its near the threshold for high voltage.

Any voltage 48 Volts DC or higher shall be considered high voltage.

Does this mean 42 V DC is not hazardous, no. Think what would happen if you were to disconnect a 12V DC battery and started with the positive side first and touched your tool to the negative body ground! The arc caused by the electrical short can severe a mechanic's wrench or screw driver. When the voltage approaches the high voltage threshold, the risk of electrocution increases rapidly. That is not to say that below this threshold an individual can not suffer a lethal current.

Late model Toyota/Lexus hybrids operate on multiple voltage systems:

12V DC (low voltage)
37-42V DC (low voltage)
300V DC/AC (high voltage)
650V AC (high voltage)

High Voltage Color Coding

All high voltage cables are color coded bright orange, as recommended by the automotive electrical standards developed by Society of Automotive Engineers (SAE).

There are NO color code standards for voltages below the threshold of high voltage. GM on their own has identified intermediate voltage (above low voltage and below high voltage) with bright blue colored cables for their hybrid systems. This was done to identify the higher electrical potential for responders. By SAE standards, the BLUE intermediate voltage cables are NOT high voltage as rumored by some presenters. However, there is a higher potential for burns, shock and electrocution than with a low voltage current.

It does need to be pointed out that NO hybrid high voltage cables are located in any of the normal extrication cut/push zones. Rumors of high voltage cables in the pillars, roof rails or rocker channels are just that, rumors and unfounded

Hybrid Myths

Question : Will I be electrocuted if I touch a hybrid vehicle in a crash?
Answer: Other than if an external power source such as a down power line, no and this is no different than safety provided for a conventional vehicle rescue. The hybrid high voltage system is isolated from the body chassis.

Question: Will I be electrocuted if I touch a hybrid vehicle submersed in water?
Answer: No, while there maybe some electrical leakage, it will not be detectable simply by touching the body or frame of the vehicle.

Question: Is it necessary to call for a HAZMAT response if the high voltage battery pack is ruptured during a crash?
Answer : No, there is not enough electrolyte in the individual modules or in the entire battery pack. Leakage will be very minimal if at all, and usually will be contained with in the modules even if the casing was breached during a catastrophic crash. The electrolyte is considered a gel, having the consistency of a machine oil and is absorbed within a fiber material between the metal plates. Spills can be cleaned up with a suitable absorbent for a strong base, diluted with water and neutralized with vinegar.

Question : At a recent Toyota hybrid crash we saw a clear fluid leak and grayish vapor coming from the trunk, was this from the high voltage NiMH battery pack?
Answer: No, beside the HV battery pack, there are 12V conventional automotive batteries. In a severe rear end or offset crash the 12V battery maybe subject to impact. The reaction seen was similar to that of a conventional vehicle when the 12V automotive battery is ruptured during a crash.

Question: At a crash, is there a chance that the high voltage system will electrify the vehicle's body chassis?
Answer : No, there are several automatic sensory devices that will stop the high voltage flow. The SRS ECU upon activation of the airbags, will also send a signal to the hybrid system computer, the computer will then open the high voltage relays to the HV high voltage battery pack; preventing the high voltage flow from the battery pack. In essence, there are checks and balances to prevent this situation.

The information above was obtained from Extrication.com, compiled by Ron Shaw. Ron is a contributing writer for the Carolina Fire Journal. Questions about the above information can be forwarded to Ron at the following Email: rshaw@extrication.com

Hybrid and Fuel Cell Emergency Response Guides

Below you will find Emergency Response Guides by the manufacturers.
Click on the link and a PDF file will open.

Hybrid Information