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Vehicular Rescue

Generic Rescue Task 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:

1. 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.
2. 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.
3. 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 a 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. DO NOT 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:

1. Shuts down the hybrid system
2. Shuts down the fuel pump
3. Stops electrical flow to the SRS ECU
4. 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 uses the vehicles power to your advantage prior to disabling such as, but not limited to: Powering down windows, open locks/latches, move electric seats.

Relating the Past with the Present
In my programs I relate to innovative vehicles with the past. 100 years ago a vehicle carrying a 12V lead acid battery and a gallon jug of gasoline by today's standards would be considered a hazard. And, its not like the operator of the wagon did experience hazards either. If the operator stood in front of the horse he could get kicked, if he stuck out his hand to the horse's mouth he could get bit, if he stood behind the horse he could get kicked and if he didn't watch where he stepped he could be contaminated by spent fuel in the form of, well I think we all can figure that out without great detail. Today we have evolved from very simple vehicles of the past to complex vehicles of the future.

The emergency responder has trained how to deal with hazards related to the conventional vehicle. Why is this, because information is readily available, proper training and experience. Can't we relate to hazards associated with gasoline and other fuels, no one refuses to go to a vehicle crash because there is a gasoline spill. So why should handling a hybrid vehicle with both gasoline and high voltage be any different. The information is readily available for departments, Extrication.Com provides links to current hybrid ERGs for all the manufacturers offering downloads. And, all of the ERGs are downloadable as a free service to any emergency responder.

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 this is 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 for a minute 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! However, 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:

1. 12V DC (low voltage)
2. 37-42V DC (low voltage)
3. 300V DC/AC (high voltage)
4. 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.

Risk Management
The emergency service is risk oriented, during an emergency we operate within an acceptable level of risk. Responding to and operating within the HOT Zone of a hybrid crash is an acceptable degree of risk. It is unwise and foolish to go into a burning building with out the proper training, PPE or the tools to perform the task expected of you. Conversely, agencies also have the responsibility to educate their members to all hazards associated with vehicle rescue.

Hybrid vehicles have been around since 1999 in North America and are quite common in most townships in the US and Canada. Departments have the responsibility to provide the proper training and responders have a responsibility to train to the accepted skills level for their job. There is enough information for training officers to develop an in house hybrid vehicle rescue training program.

Patient care should not be compromised because a vehicle maybe a hybrid. If you have been trending production and sales, more and more vehicles are being made available as hybrids. This is especially true with the drastic rise in fossil fuel costs. Toyota has made a commitment to the consumer with a recent statement that in the near future every model line will be offered as a hybrid. Expect to see a dwindling sales and production in conventional vehicles as more and more hybrids are introduced. The fossil fuel vehicle in some of the reader's life time be be come as extinct as the dinosaur.

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 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, there are 12V conventional automotive batteries, in a severe rear end or offset crash the 12V battery maybe subject to impact. The reaction you saw is 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.

What Can I do?
Start by educating yourself to hybrid technology, now is the time not at 0300 in the morning. Fuel cell vehicles are knocking at the door and will be available to the consumer within the next decade. This web page provides links to the current manufacturer's hybrid ERGs, take the opportunity to download this information for your agency.

NEW for 2008 "40-hour Vehicle Extrication: New Technology Train the Trainer"
Extrication.Com will be presenting a new program for 2008; "40-hour Vehicle Extrication New Technology Train the Trainer" Trainers will learn about hybrids from the Extrication.Com consultant who has co-written the leading hybrid manufacturer's ERGs since 2001, not from someone who has read the ERG. You will also learn about other alternative fuel vehicles, SRS, ROPS/RPS, crash theory, and new alternative extrication techniques.

The attendees will be required to do research and work together to develop a class New Technology PowerPoint presentation that they can take back to their own departments. At the end of this program, the trainers will become the Subject Matter Expert (SME), not the instructor trainer. This program is designed to allow the attendees to become program developers for their own department, enabling their presentation the ability to expand and not become out dated as with most "canned" extrication training programs.

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