[Jamo]

About 5 years is about right. That's what most sanctioning bodies require. However--each mfg has different ideas and specifications. Find out who made it and contact them. There should be a stamp somewhere indicating the make date.

Watch what you put in there. Different materials are used for different fuels--so you want to know what you have. Unless it's made for alcohol--don't use ANY additives with alcohol in them.

Safety is what you gain with a fuel cell. Long term durability is what you lose.