2000
There was a suggestion that the shelf life of some helmets could be as short as 2 or 3 years. There would be implications for other adventure sports helmets.
It can be argued that a helmet is demonstrably fit for purpose if, after a certain age, it has been visually inspected from time to time and maybe a sample of the batch has been tested. The condition of the cradle and rivets should be considered as well as the shell. Sample testing could be fairly basic, including hitting it with a hammer and pulling vigorously at the cradle. The test sample should of course be discarded.
To put this issue in perspective: we have no evidence of any serious accident arising out of the structural failure of a kayak helmet.
