More facts about Helmets from the American College of Emergency Physicians(ACEP)

Jay Beattie wrote:

...the last time I was at the ER, my doctor was
hot. Smoking hot. Victoria's Secret hot. I could only imagine the
things she was trained in -- emphasis on imagine.

What, your cellphone camera was on the fritz?!?

Bill "sheesh" S.

Jay Beattie wrote:

Looking at that bike was like looking at a fussy but hot old girl
friend. *You say wow, she is so beautiful, and then you remember much
trouble she was.

I worked on an exceptionally well-preserved 1976 Peugeot PY-10 a few
days ago. Every part of that bike was beautiful, in 1976 and today.
Today it came back in with a loose (wrong-hand threaded) fixed BB
cup.

It doesn't matter how nice a French threaded bike is, I really want
nothing at all to do with it. And French threading isn't the only
unfixable affliction an otherwise lovely old bike can have.

Chalo

MikeWhy wrote:

Tim McNamara wrote:

Properly designed and manufactured safety gear works within the
parameters it was designed to meet. *The problem with bike helmets is
that they are under-designed for the forces involved.

You must have missed the reference a message or two back. The impact design
parameters are very similar to those for motorcycle helmets.

The test that bicycle helmets must pass may indeed resemble the test
for motorcycle helmets. But it bears little resemblance to the real-
world situations in which we actually hit our heads. That's why
bicycle helmets can be designed so wildly divergently from all other
crash helmets. They are not designed to protect human beings' real
heads from real crashes-- they are for registering permissible values
on accelerometers in disembodied head forms for certain vertical drops
onto controlled surfaces.

Motorcycle racers wouldn't trust a hat like that, even if it passed
the same instrumented tests as their Arai or Shoei brain buckets. And
they'd be right.

Chalo

On May 20, 9:19*pm, " wrote:

(quote):The killer—the hardest Snell test for a motorcycle helmet to
meet—is a two-strike test onto a hemispherical chunk of stainless
steel about the size of an orange. The first hit is at an energy of
150 joules, which translates to dropping a 5-kilo weight about 10 feet—
an extremely high-energy impact. The next hit, on the same spot, is
set at 110 joules, or about an 8-foot drop. To pass, the helmet is not
allowed to transmit more than 300 Gs to the headform in either hit.
(end)

The table you referred to, for bicycle helmets, doesn't say anything
about multiple drops, and in the Snell B95 test, the helmet has one
drop at 110 joules.
The similarities a a 5 kg "head" and "failure above 300g's" of
impact. IOW, modeling the head for weight and impact resistance.
Again, the bike helmet gets dropped from 2.2m, or 7.22 ft. Once.

Wow, drop a turd, declare victory, and leave. Great tactics, bub.
(just seeing if you really really left there, nothing personal
intended)

It is worth mentioning that ANSI and Snell-certified bicycle helmets
are no longer available. Whatever real protection those standards do
or don't assure is now moot. Manufacturers have opted to conform to
the less challenging DOT standard-- which is an astute move on their
part, since bicycle helmets can't possibly live up to the unrealistic
hype surrounding them in any case.

Chalo

On May 20, 11:58*pm, Tim McNamara wrote:
In article ,

*"MikeWhy" wrote:
Tim McNamara wrote:
In article , "MikeWhy"
wrote:

Safety gear works.

Properly designed and manufactured safety gear works within the
parameters it was designed to meet. *The problem with bike helmets
is that they are under-designed for the forces involved.

You must have missed the reference a message or two back. The impact
design parameters are very similar to those for motorcycle helmets.

Then god(s) help motorcyclists!

Motorcycle helmets are the result of a long period of practical trial
and error, starting long before anyone considered doing instrumented
tests on artificial severed heads. Their form had already been
settled to a large degree before there was a system to game. Same
goes for military aviator helmets.

The things about a motorcyclist's or aviator's helmet that allow it to
pass instrumneted certification tests may not be the things that
contribute the most significantly to its practical protective
qualities.

The things that distinguish a motorcycle or aviator helmet from a
bicycle helmet may be precisely the things that make them more
effective at preventing real world injuries. That's what I'd guess,
given the similarities shared by other crash helmets that are not
characteristic of bicycle helmets.

I think a simplified or minimal helmet that diverges from established
crash helmet design would likely be a lot more useful for car drivers
(who are strapped down in a prescribed way in an easily characterized
space under a limited set of operating conditions) than for cyclists
(who retain all the usual degrees of freedom of an unconstrained body
in a crash).

Chalo

On May 20, 11:11*pm, "MikeWhy" wrote:
wrote:
On May 20, 7:12 pm, "MikeWhy" wrote:
AMuzi wrote:
"MikeWhy" wrote:
Safety gear works.

Tim McNamara wrote:
Properly designed and manufactured safety gear works within the
parameters it was designed to meet. The problem with bike helmets
is that they are under-designed for the forces involved.

MikeWhy wrote:
You must have missed the reference a message or two back. The
impact design parameters are very similar to those for motorcycle
helmets.

"Similar" only in that they both specify some mass and
acceleration numbers.

http://www.webbikeworld.com/motorcyc...T-standard.htm

"Similar" in the sense that the impact failure criteria are largely
identical, possibly even higher for the Snell
B-95.http://www.bhsi.org/stdchart.htmTim'sassertion is that bike
helmets are under-designed for the forces involved. I see no
credible reference to
support that claim. I am pleased that bicycle helmets are designed to
essentially the same criteria as motorcycle helmets. And with that,
I really
am out of this conversation.
Didn't find a table, did find a quote:

http://www.motorcyclistonline.com/ge...helmet_review/
index.html

(quote):The killer—the hardest Snell test for a motorcycle helmet to
meet—is a two-strike test onto a hemispherical chunk of stainless
steel about the size of an orange. The first hit is at an energy of
150 joules, which translates to dropping a 5-kilo weight about 10
feet—
an extremely high-energy impact. The next hit, on the same spot, is
set at 110 joules, or about an 8-foot drop. To pass, the helmet is not
allowed to transmit more than 300 Gs to the headform in either hit.
(end)

The table you referred to, for bicycle helmets, doesn't say anything
about multiple drops, and in the Snell B95 test, the helmet has one
drop at 110 joules.
The similarities a a 5 kg "head" and "failure above 300g's" of
impact. IOW, modeling the head for weight and impact resistance.
Again, the bike helmet gets dropped from 2.2m, or 7.22 ft. Once.

Wow, drop a turd, declare victory, and leave. Great tactics, bub.
(just seeing if you really really left there, nothing personal
intended)

What point are you making? That bicycle hats are under-designed because they
don't account for the motorcyclist's potential tumbling? First, the claim
was they can't survive your pinching and crumpling. And now, they're
inadequate because ... I've lost track. What point are you making?

From my POV, the bicycle helmet is adequately designed for the range of
speeds reasonable for bicycles. Double impact for a motorcycle helmet is
reasonable because the speeds involved can cause tumbling. Motorcycle and
bicycle helmets are sacrificial, single use items. Their design and
construction are based on rational criteria for survivability, appropriate
for their different intended uses. They are single use because, presumably,
anything substantial enough to retain their integrity through multiple
events would be impractically large, heavy, and expensive. Does that cover
everything? Did this last paragraph add anything new that hasn't already
been said recently?

It clearly is time for me to go. You've demonstrated only an unreasoning
dislike of helmets. I don't care to waste another minute on this.

No no no.
Bike helmets and motorcycle helmets are two different animals. The
standards for bike helmets are much lower, not "similar" except for
weight of the test head and impact threshold limit.
I distrust helmets IRT the magic power of the foam. I have a reasoned
dislike of helmet laws.

Cyclists are the lowest form of life on the food chain. MHL's for
cyclists are scapegoating mechanisms.
--D-y

On 19/05/10 1:22 PM, wrote:

The "magic foam" sobriquet is completely appropriate IRT "my helmet
saved my life" stories.

So if you're in a vehicle crash and your airbag deploys, and nylon and
nitrogen save your life do you claim that it's "magic nitrogen?" Or
magic nylon. How could some gas and nylon possibly protect you? Oh wait,
in a 60mph head-on crash, you'd still be dead even with an airbag, so
clearly air bags are under-designed for the forces involved and are
hence worthless. In fact the mere presence of air bags in cars has
reduced the number of cars sold as people give up driving--just look at
car sales figures for the last two years.

The "magic foam" and "foam hat" schtick are used by those that either
unintentionally uninformed or intentionally dishonest, with the latter
being more probable. No doubt they really do understand why EPS foam is
used in a plethora of products, including helmets, where the need for
impact protection and light weight are key requirements. They've lost
the argument based on statistical and scientific fact, so being smarmy
is their only choice.

Chalo wrote, On 5/21/2010 3:19 AM:
snip
It is worth mentioning that ANSI and Snell-certified bicycle helmets
are no longer available. Whatever real protection those standards do
or don't assure is now moot. Manufacturers have opted to conform to
the less challenging DOT standard-- which is an astute move on their
part, since bicycle helmets can't possibly live up to the unrealistic
hype surrounding them in any case.

Chalo

Most helmets manufactured by Specialized comply with SNELL standards.

--

Paul D Oosterhout
I work for SAIC (but I don't speak for SAIC)

On May 21, 9:11*am, SMS wrote:
On 19/05/10 1:22 PM, wrote:

The "magic foam" sobriquet is completely appropriate IRT "my helmet
saved my life" stories.

So if you're in a vehicle crash and your airbag deploys, and nylon and
nitrogen save your life do you claim that it's "magic nitrogen?" Or
magic nylon. How could some gas and nylon possibly protect you? Oh wait,
in a 60mph head-on crash, you'd still be dead even with an airbag, so
clearly air bags are under-designed for the forces involved and are
hence worthless. In fact the mere presence of air bags in cars has
reduced the number of cars sold as people give up driving--just look at
car sales figures for the last two years.

Sounds like I really hurt you, bro.

The "magic foam" and "foam hat" schtick are used by those that either
unintentionally uninformed or intentionally dishonest, with the latter
being more probable. No doubt they really do understand why EPS foam is
used in a plethora of products, including helmets, where the need for
impact protection and light weight are key requirements. They've lost
the argument based on statistical and scientific fact, so being smarmy
is their only choice.

Uninformed and/or dishonest apply to the docs and others who claim
"your bicycle helmet saved your life". There's no way to tell, short
of duplicating the accident with and without helmet (just reminding
you there). Authoritarian mindsets want to see uniformity, rule
obeying, compliance. Dr. Crocker was so sure he was going to
demonstrate bicycle helmet effectiveness that he set himself up for a
big, big public fall. Did you read the info posted here on that? They
couldn't find "effective" swatting with both hands, as the saying
goes, and extending the study for a year, and for all I know altering
diagnostic criteria. Wouldn't put it past them...
You should maybe go back and read that report Carl linked to, knowing
something of the history of how the Austin City Council sneaked a
helmet law through in "Emergency Session" and maybe look at the unholy
alliance between former Mayor Bruce Todd and Crocker et al. They were
going to get that MHL in any way possible; there's stuff on the web
from local bloggers (who also recount police encounters with MHL non-
compliers, including people being thrown into jail).

I don't like MHL's. You claim not to favor MHL's but then you go on
and on "debunking myths" (not, IMHO, and I did read your stuff) to
proclaim the wonderful effectiveness of magic foam hats (my
description, of course). What are you doing here?

Here's the deal: if the foam in my friend's helmet had compressed, I
could get on board with you, at least to the extent of "lessening
injury".
Since the foam did not compress, and this by a very careful visual
inspection, but broke, only staying together because it was glued to a
flimsy shell that also broke, and my friend did get KO'd by "a fall
backwards out of a chair", I'm not going for "lessened the impact".
Even though I'm sure that the helmet did in fact lessen the impact by
at least the small amount the "break a helmet without a head in it,
it's easy" folks talk about; however, you're talking about compressing
foam and in my example-- thank goodness the only one I've ever seen--
the foam didn't work as touted.

Smarmy? Read your own "magic nitrogen" passage above. Noting, air bags
started doing a lot better after they dialed the power back and
stopped decapitating babies and little people.
But that does raise the question of how much actual research has been
done for bike crashes, similar to the crash test dummy automotive
films seen on TV where air bag (and actual construction details)
design and effectiveness are studied.
I'm betting "none", certainly not at the level that Volvo and Mercedes
Benz (and maybe Lexus?) do it. Now there's some research that gets
close to real world, with various types of known-to-occur impacts
modeled, not just putting a weight in a magic foam hat and dropping it
(once!) onto something; although Volvo got their butt in the buzzsaw
several years ago when they were caught reenforcing car roofs (with
wood!) to demonstrate rollover protection for a TV commercial. Loose
cannon field operatives, bad news g.

So, again, what are you hoping to accomplish here? Doesn't look like
you're getting many converts. Just sayin'.
--D-y

In article
,
Chalo wrote:

On May 20, 11:58*pm, Tim McNamara wrote:
In article ,

*"MikeWhy" wrote:
Tim McNamara wrote:
In article , "MikeWhy"
wrote:

Safety gear works.

Properly designed and manufactured safety gear works within the
parameters it was designed to meet. *The problem with bike
helmets is that they are under-designed for the forces
involved.

You must have missed the reference a message or two back. The
impact design parameters are very similar to those for motorcycle
helmets.

Then god(s) help motorcyclists!

Motorcycle helmets are the result of a long period of practical trial
and error, starting long before anyone considered doing instrumented
tests on artificial severed heads. Their form had already been
settled to a large degree before there was a system to game. Same
goes for military aviator helmets.

The things about a motorcyclist's or aviator's helmet that allow it
to pass instrumneted certification tests may not be the things that
contribute the most significantly to its practical protective
qualities.

The things that distinguish a motorcycle or aviator helmet from a
bicycle helmet may be precisely the things that make them more
effective at preventing real world injuries. That's what I'd guess,
given the similarities shared by other crash helmets that are not
characteristic of bicycle helmets.

I think a simplified or minimal helmet that diverges from established
crash helmet design would likely be a lot more useful for car drivers
(who are strapped down in a prescribed way in an easily characterized
space under a limited set of operating conditions) than for cyclists
(who retain all the usual degrees of freedom of an unconstrained body
in a crash).

They hate us for our freedom.