Helmets-- DOTand/or Snell certified

Message

qwerty · #11 Unread post by **qwerty** » Mon Dec 04, 2006 6:14 pm

Snell isn't what it's cracked up to be. Last I checked, Snell and DOT test a helmet's ability to take a hit without damage. What they should be testing is the amount of energy transfered to the head inside.

jonnythan · Mon Dec 04, 2006 6:18 pm

qwerty wrote:Snell isn't what it's cracked up to be. Last I checked, Snell and DOT test a helmet's ability to take a hit without damage.

No they don't

qwerty wrote:What they should be testing is the amount of energy transfered to the head inside.

That's what they test.

jonnythan · Mon Dec 04, 2006 6:20 pm

black mariah wrote:Exactly. What you want to see after an impact is a crack on the side OPPOSITE of the impact point. This indicates the shock traveled around the outside of the shell and met somewhere else. *snap*

Why do you want to see a crack at all? The only thing that matters is how much energy the foam absorbed by compressing. Apparently in Motorcyclists' testing many helmets (the plastic ones) didn't crack at all.

#14 Unread post by **Sev** » Mon Dec 04, 2006 6:50 pm

Ideally the inner foam will compress and prevent your head from stopping to suddenly. While the hardened outside shell should prevent the asphault from grinding it away like an angle grinder gone wild.

black mariah · Mon Dec 04, 2006 6:59 pm

Sevulturus wrote:Ideally the inner foam will compress and prevent your head from stopping to suddenly. While the hardened outside shell should prevent the asphault from grinding it away like an angle grinder gone wild.

In the even of a huge impact it would be preferable to have the outer shell shatter, similar to a tanks ablative armor which will shatter or explode outwards in order to minimize the damage caused to whatever is underneath.

What he said. The outer shell acts like a crumple zone in a car. It absorbs impact and redirects it AROUND your head. The shockwave emanates from a point then meets itself at another. With enough amplitude it'll crack the shell. This is a GOOD thing since it indicates a great deal of energy dissipation.

#16 Unread post by **Sev** » Tue Dec 05, 2006 4:04 am

I made a mistake when I said ablative armor, I meant ceramic armor. Which is/are two totally different things. But the concept is the same. Sorry for the confusion.

anarchy · #17 Unread post by **anarchy** » Tue Dec 05, 2006 4:43 am

check out this headgear...

maybe one day this stuff will be in our helmets...

black mariah · Tue Dec 05, 2006 5:21 am

anarchy wrote:check out this headgear...

maybe one day this stuff will be in our helmets...

Probably sooner rather than later. Give the manufacturers time to test it.

anarchy · #19 Unread post by **anarchy** » Tue Dec 05, 2006 5:40 am

black mariah wrote:
anarchy wrote:check out this headgear...

maybe one day this stuff will be in our helmets...
Probably sooner rather than later. Give the manufacturers time to test it.

hopefully soon...

qwerty · #20 Unread post by **qwerty** » Tue Dec 05, 2006 4:30 pm

jonnythan wrote:
qwerty wrote:Snell isn't what it's cracked up to be. Last I checked, Snell and DOT test a helmet's ability to take a hit without damage.
No they don't

qwerty wrote:What they should be testing is the amount of energy transfered to the head inside.
That's what they test.

When did they change? I can't find the actual standards and test procedures currently in use anywhere.