I'm having trouble interpreting why this is bad.
Quote:
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According to The New York Times, in order to attain the SNELL M2005 certification, a helmet needs to be able to withstand that impact of a small steel sphere, twice, with the headform inside the helmet experiencing less than 300 times the force of gravity (300 g's).
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As the article says, that is a huge amount of accelerative force. The DOT standard allows at most 400 g's. So, technically, by that description, the Snell standard requires a helmet transfer
less force on a headform than a DOT-only helmet would. Furthermore, critics also cite the 2-impact test. Again, I'm having trouble seeing how this is bad compared to DOT-only. The Snell helmet is guaranteed to transmit less than 300 g's to a headform over 2 hits in the same spot. A typical DOT-only helmet can transmit up to 400 g's (more than a Snell), AND it doesn't have any requirements on a second impact. That means it can transmit as much as the full unimpeded force of impact the second time around, and still be DOT certified.
How does absorbing more impact result in a helmet being too rigid? The more rigid a helmet, the higher the amount of g's it would transmit, right? The biggest criticism of Snell that I can agree with is that they didn't lower the amount of g's transmittable by a helmet in their last revision. Instead, they simply said it had to withstand two impacts instead of one. That's my understanding of what I've read. Either way though, the headform is probably in better shape after testing than the DOT-only certification.
Anyways, also remember that Snell is certified by Snell testers. DOT standards are met on the good 'ol fashioned honor system.
- Dr. Joe Schmoe, PhD