In the grandscale of things they are not that common and if you do get called to an incident involving one away from the airport its most likely will have been fired already.
SO far they have only been fitted I think to low wing type aircraft so if it has the wing on the top of the aircraft it won't have one.
If it has two engines again it won't have one.
If its made out of metal again it won't have one.
If it low wing made out of fiberglass looking stuff look for the sticker it should have a red box round the dangerous bit.