X2, except for maybe the SNELL part IMO. I feel SNELL has to strict of a rating and after reading the requirements stats, tests and studies on SNELL approved helmets I feel they do not provide the proper protection for the less violent non life threatening, more common crashes. A helmet is designed to break down and absorb the energy of the crash before it reaches our oh so important gray matter. SNELL has such strict testing that helmets that have paid to have this rating (another issue I will explain in a minute) do not break down as easily on the more common crashes. ECE and DOT have different requirements. After reading the stats, I feel that they protect better against smaller crashes better. They are also safe in big crashes. SNELL is superior in crashes where your helmet bounces of the hard object which you have chosen to drive your brain into then repeat this action. SNELL has requirements to protect from multiple bang ups in one accident ie:crotch rocket crashes and your head bounces on the pavement more than once really hard. To reach this high of a standard the material that breaks down has to be so hard that it does not easily break down on smaller crashes. Also, because of this ECE and DOT tend to have lighter helmets without having to use carbon fiber. With all that said a helmet that is on DOT approved may also meet SNELL requirements, the company just did not want to pay to put on their sticker. Yup even if a helmet meets the requirements that alone does not mean they will be SNELL certified. They have to pay a lot of money for that little sticker.
This is the way I understand it. I did quite a bit of research because my brain has been bounced waaaay to many times and I have had several concussions. To the point where the doc told me I should quit powersports and I shouldn't even ski (majority of my concussions are from skiing). This is all what I put together. So IMO if you want protection against multiple shots in one accident find a SNELL, if you want protection from normal head shots go ECE or DOT. Multiple shots does not mean you can have a good crash where you bang the helmet and it does its job and still use that helmet in the future. ANY helmet is designed to break down upon impact. If you have a good impact the helmet broke down and it is time to replace it. Also the material breaks down over time. I see people wearing old helmets all the time. They are only going to work against blunt trauma, not brain banging (concussion) as the material can no longer break down to protect as it already has over time. the material breaks down so the energy does not reach your brain, or least less of it in hopes that your brain does not smash against your cranium. I wore a SNELL helmet in a small accident (this is before I had done research) and got a concussion. I now wear DOT and ECE helmets and haven't had a concussion in 2 years. Once you have a concussion it becomes easier to get another one. If you get a second even easier for a third and so on.
Just my .02. Of course I have had many concussions so I never really know what I am talking about from minute to minute.
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