If you look closely, you can see that the stored gas inflator for the roof airbags is mounted on the rear C-pillar and note how extremely low the inflator is.
Photo credit: Courtesy of Ron Moore
If a crew were considering total roof removal and they stripped the trim and found this inflator unit, they would probably realize that there isn't enough room to cut below it.
Topic: Unplugging the Stored Gas Inflator
As rescuers study how to deal with stored gas inflators for roof-mounted airbags, the question always comes up, "What do we do once we strip the trim and see where the inflator is?" The image of the Mercedes vehicle is a perfect example of how relevant this question is.
If you look closely at the image, you can see that the stored gas inflator for the roof airbags is mounted on the rear C-pillar. But what is really important is to note how extremely low the inflator is. It is almost mounted into the rear body panel.
If a crew were considering total roof removal and they stripped the trim and found this inflator unit, they would probably realize that there isn't enough room to cut below it. There is another option for this situation.
The automakers actually will allow rescuer personnel to unplug the yellow power wires connected to a stored gas inflator unit. The yellow plug that you will find a few inches from the cylinder-shaped inflator is actually a safety plug. As the ends are disconnected and pulled apart, there are small wires inside the plug ends that close the connection to minimize stray static electric charges. This means that it is safe to unplug these wires at crash scenes as long as the vehicle's electrical system has been shut down prior to unplugging.
With the stored gas inflator unit unplugged, the rescue team can cut into the discharge tubing that connects the inflator to the airbag itself. There is no pressure in the tubing which can either be a small metal tube or a rubber hose. Once cut through, the roof could be removed with the airbag still stowed along the roofline and the pressurized inflator unit left still attached to the stub of the C-pillar.
Crash Course Teaching Point:
You always want to use caution when working with any loaded airbag system. Stay out of the inflation zones. When dealing with stored gas inflators that inflate roof airbags however, one option you have is that you can unplug the yellow wires at the inflator unit without undue risk of roof airbag accidental deployment.
Be Informed...Be Ready...Beware!