One thing that many people forget is that the agent in dry powder extinguishers will "settle" and pack. This is especially true in vibration prone installations.
You need to take the extinguisher out and shake it up occasionally.
Otherwise when you need it, it could be useless.
This was what the fire inspectors told me about the dry chem extinguishers we have mounted in our shop.
Have any of you thought about an on-board system?
Seems like that would be the quickest and most effective response to a fire.
