Fire Extinguisher Requirements

[eviltodd]

I have an older fire extinguisher on my boat, but it has a gauge that's showing in the "Green" for good charge. I was told that fire extinguishers could only be so old or they wouldn't pass an inspection. Is this true? And if so, what are the requirements. I couldn't find anything about the age of extinguishers on the ODNR website. It just states the type and amount of retardant that you must have. Also, is there a similar "age" requirement for a flare gun?