Just to keep with the PSA theme. Annual inspections are not enough. Technically they need to be inspected monthly. Which is simple, is the pin still in place, is the needle in the green and is there any rust or damage to the extinguisher. I also turn mine upside down a couple of times. You should hear the chemicals cascade on the inside. If you just here a thump, or nothing, the extinguisher is no good. Get rid of it and get a new one.
The small marine extinguisher types that most of us have are disposable. Meaning they can't be recertified. They have a printed expiration date. Dispose of them once past the date. Some can be recertified but if you purchased it for under $100 it is doubtful.
FYI, I manage environmental cleanup primarily at gasoline retail stations. The big oil companies are extremely safety conscious. I have to do about 100 hours of safety training annually of which 4 hours are on extinguishers. I have also had to do actual fire response training. If you can find a reasonably priced course near you take it. You would be surprised how useful it actually is on a boat. For instance, those little marine extinguishers have less than 8 seconds of chemical in them. A small fire in a confined area like an engine room could take two canisters to put out, especially if you don't know where to aim and how to use the extinguisher. At the very least, start a small fire on the beach or in a safe place and use one of those old extinguishers to put it out.
Fair winds,
Jesse
