How long does a helmet last?

[Owlie]

If you you take a really good spill with your helmet, I heard it crack, should you replace it?

I can see keeping one for as long as a few years or so, but I'm wondering if mine is a goner.

I think the rule is that if you crash it, you should replace it, even if you didn't hear it crack. The fact that you heard it crack means that it's a goner. Please get a new one!