Common sense and good basic training. Your department should have a standard operating guideline/procedure specifically pertaining to handling MVA's. I won't knock anyone, but a few myths need to be debunked.

1. You must disable the high-voltage system. FALSE.
Just like regular cars, the standard control systems operate off the regular 12VDC battery. Disconnecting the 12VDC battery will disable ALL drive systems, including the hybrid electric motor control. When you do so, cut the NEGATIVE first. This prevents arcing between the cable stump or tool and the frame of the car and reduces risk of fire. You MAY disable the hybrid battery by means of a switch, however, many hybrids have breakers, fuses, or service disconnects that require removal. Leave these in place. They may arc during removal causing electrocution (a service technician was killed several years ago removing the service disconnect from a Toyota Prius).

2. You must disconnect all devices with batteries plugged into the vehicle. FALSE.
Although not a bad practice, virtually all new vehicles have isolated the SRS capacitors from the auxiliary power relays, eliminating the risk of back-feeding the system and charging the SRS. Of course, it doesn't hurt...

3. The SRS system runs off the high-voltage battery. FALSE.
The hybrid battery runs the electric motor. Simple as that. The alternator that charges the 12VDC battery, depending on the model, may run only with the gasoline motor, or both electric and gasoline motors. Either way, ALL other systems in the vehicle operate off the 12VDC battery.

That being said - these basic steps will help keep you safe at ANY collision scene, including one involving a hybrid.
-Check for hazards such as leaking fuel and downed wires on approach.
-Place the vehicle in park, set the parking brake, and remove the key from the ignition. If it has a proximity key, make sure ALL keys are removed from the vehicle and taken away (put them in the police car :-P).
-Chock and/or crib the vehicle to prevent movement.
-Disconnect the 12VDC battery. If you cut the cables, take negative first, and remove a 3 inch section of the cable to prevent arcing.
-At a minimum, keep an ABC class extinguisher handy for the duration of the operation.
-Remember that SRS systems have capacitors that allow the system to function for a period of time after the 12VDC battery has been disconnected. The time varies with make and model from 5 seconds to 10 minutes. A little research (or a Holmatro Extrication Guide) will help you determine if the capacitors have discharged.

If extrication is required, take the time to look before you cut and pry. Expose your pillars and rails to check locations of SRS and other safety systems. Avoid high-voltage system components. If you MUST remove a high-voltage component, find the system disconnect or breaker and pull it to isolate power to the battery pack. DO NOT take apart the battery pack itself. They can usually be removed with a few wrenches and ratchets or a sawzall to cut the bolts only.

Be smart, and use your head. It's just a car with some fancy electronics in it. Proper size up and common-sense tactics will keep you safe for the most of it. A little research and a few Hybrid Vehicle ERG's from manufacturers will take you the rest of the way. Best of luck and stay safe out there.

Eric go to NFPA EV Training, there is a training course you can take on the chevy volt which is an electric car as well as you can down load information on the hybirds