Not wishing to start a helmet debate but I've heard a zillion anecdotes where people claimed that they would have been severely injured or worse if they hadn't had a helmet on. But, and it's a controversial but, how do we know for sure? There are no measurements or recordings to be had after the fact and I'm pretty sure that no one is going to go out and try to repeat their accident without a helmet.
And then there is the helmet itself which increases the size and weight of the head. I know in my construction field, I wasn't required to wear a hard hat until after at least 20 years of work and I was amazed at how any times that I hit my head on bridge beams and such after that. I don't ever remember smacking my head before I started wearing a hard hat. My own anecdote, I know.
Regardless, I wear a helmet religiously. Just always wondered.
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