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What does ASTM/SEI stand for?

From: Lori

Dear Jessica, this probably sounds really stupid, but could you please tell me exactly what ASTM/SEI stands for? I'm buying helmets for my children, who are taking riding lessons. Their instructor said that they must have helmets that are ASTM/SEI approved, but she wasn't able to tell me what the letters stand for, just that they mean the helmets are really protective. It probably doesn't matter, I'll buy the approved helmets anyway, but I'd really like to know. I do know that I'm supposed to buy a new helmet if a kid ever has a serious fall and lands on his head, because the old helmet won't be protective anymore, but I'm really not sure how that works either. Thanks! Lori

Hi Lori! That's a perfectly good question, and I'll bet that you and your instructor aren't the only people who don't know the answer - but who DO know enough to buy the right helmets.

ASTM stands for the American Society for Testing and Materials. The ASTM sets safety standards for many different materials, including those that go into sports equipment - including protective helmets designed for equestrians.

The ASTM consults with experts in various fields (including medical) and then sets the standards for equestrian helmets. These standards include impact absorption and harness design and strength. When the standards are established, the job of the ASTM is done - until new developments in product design or engineering, or new medical information, makes it necessary to revise and update the standards.

This is where the SEI comes in. The ASTM determines the standards; the SEI (Safety Equipment Institute) then tests and inspects the various models and types of helmets to ensure that they are being manufactured to standards that meet or exceed the current ASTM standards.

So there you have it: The ASTM sets standards and the SEI checks on manufacturer compliance by testing the helmets.

As for the "new helmet after a fall" rule - yes, that's a very good policy. Since the way the helmets "work" is that their liners collapse internally to absorb the shock of impact, since a collapsed liner does not "spring back" into place, and since it's often impossible to SEE this collapse whether you're looking at the helmet from the inside or the outside, it's just good sense to replace any helmet that has already done what it was designed to do. As you obviously understand already, helmets can be replaced - humans can't.


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