I'm crushed. I didn't want to believe at first, but the more I look into it, the more it becomes clear that the Snell rating, to which I've trusted my life, is misguided at best and a scam at the worst.
The physics is only a little complicated, but basically the Snell testing methods are flawed: they insist a helmet must survive *two* impacts to the same place. The only way to do this is with an elastic outer shell (that rebounds to take the 2nd hit) and an inner shell that doesn't fully compress on the first hit (robbing the crash victim of the much needed de-acceleration during compression).
A popular motorcycle magazine, Motorcyclist, hired an independent lab to test a variety of helmets and, basically, the ones you think are the best ("highest" rating and most $$$) are killing people.
The full article is here, it's a great read: Scientific Helmet Drop Test
They include Snell's retort, which I can say definitively, contains wild inaccuracies. For example, the Snell foundation actually states:
All the standards, Snell M2000 and M2005 included, presume a threshold model of injury. That is: so long as a threshold G limit is not exceeded, there will not be a serious injury. A corollary conclusion is that any G exposure not exceeding this G limit is no better or worse than any other G exposure not exceeding this limit. If a G exposure below this limit is safe, another exposure 40 G's lower cannot be any safer.
This is patently false, especially when it comes to brain trauma. I spend some of my time working at a Parkinson's Disease foundation. There is a correlation between brain trauma when you're younger and getting Parkinson's when you're older. Brain cells don't grow back. Knock yourself out, even "lightly", and you're doing irreversable damage that may not be able to be measured by your IQ score. The softer the blow, the better it is for your brain. Period. How the Snell Foundation could even suggest otherwise shows that they clearly have no regard for facts or reality. They've lost all credibility with this statement alone.
See for yourself, go to their site and click www.smf.org/, click on "Research/Funding". See anything funny? Not a single update since the mid 1990's. The website looks like it was made in some kid's garage. What are they doing with all the money they get from the helmet manufacturers? Maybe they're spending it on their Board of Directors (click on "about Snell" and then "Board of Directors"). I don't know why else they would sit silently by and watch their foundation kill people. Wake up, guys.
So, now it's clear that a cheap helmet, that wasn't mis-engineered to pass Snell, will tend to protect your head BETTER than a Snell rated helmet. Sounds crazy, sadly it's true. So what's a boy to do? "Got a $100 head? Get a $100 helmet." is a tough message to get out of your brain. Plus, the more expensive helmets usually have nicer visor systems, better venting, etc., that the higher price point can afford.
Here's the answer: get a Schuberth: www.schuberth.com
The Schuberth is not sold in the US and doesn't have the Snell rating or even the US DOT rating. It does, however, have the much more well thought out European rating (ECE 22-05, accepted by more than 50 countries). It's basically impossible to build a helmet that passes Snell and passes Euro standards -- the Euro standards are too good, and Snell is mutually exclusive with any good standard. It is also, as you'd expect, THICKER, duh, allowing for a longer distance over which to de-accelerate as it crushes, so lower g's to the brain.
I just got my first one. It's pretty much the most expensive helmet you can buy, is more comfortable than any I've ever worn, and has some really cool built in features (internal flip down visor, for example -- totally Ninja). I'm in love.
Oh, and to the Snell Foundation, for lying to us all these years (or, at best, not taking a reasonable scientific approach), risking our lives in your pursuit of profit and being too thick-headed to admit a mistake when it's been conclusively proven to you: I flip you the proverbial bird as I pass by. I know the foundation meant well when it started, but you guys will have to live with what you've done. Even more I hope that you will come to the realization that what you've been doing is wrong, drop the double-impact test, lower the g-threshold substantially and come out with a Snell rating that actually makes the helmet safer and not more dangerous.Posted by rick at April 3, 2010 01:54 PM