I attended a boating fire safety session with some mates last night at http://bmys.com.au/, I even got to put a fire out
Lessons learnt:
A 1kg fire extinguisher is pretty useless in novice hands
It is better to have one big fire extinguisher than two small ones
A fire blanket is good to smother a small fire before it becomes a big fire
You should ensure you shake your fire extinguisher often to prevent the powder settling
Even a small fire is hot!