Cycle helmets - major study

Guy Chapman said:

I've not seen any real evidence of torsional injuries in cyclists.

Broken necks do happen. Mind you, I don't think it's very significant, but I also don't think the
added protection against direct impact is very significant, and this is consistent with the
statistics.
--
David Damerell <[email hidden]> flcl?

In message <[email hidden]>, David Damerell
<[email hidden]> writes

Quoted message said:

Broken necks do happen. Mind you, I don't think it's very significant,

I would have thought a broken neck was very significant. ;-)
--
Michael MacClancy

Paul Smith said:

roads.dft.gov.ukindex.htmOpen ↗

The DfT of course has an agenda - they are now quite open about their desire to keep helmet
legislation on the agenda. The reason for this is simple, and consistent with many other aspects of
road "safety" policy: they have become accustomed to thinking the motor lobby way.

The motor lobby is wary to the point of paranoia about anybody considering accident reduction at
source as a means of improving road safety. Consider the possibilities this raises: raising the
standard of the driving test, reducing speed limits across the board, automated speed limiting,
harsher penalties for bad driving, even police activated remote engine immobilisers. So for over
half a century the road lobby has worked at setting the road "safety" agenda into a particular
mould: that of reducing the severity of consequences of poor driving, rather than addressing the
poor driving itself.

So, when considering cyclist safety the Government (and the road "safety" establishment) is
conditioned by decades of practice to consider that helmets are a valid safety measure, even though
they do absolutely nothing to stop accidents in the first place, and provide no proven protection in
crashes likely to be serious or fatal. Any complete analysis shows that:

- helmets are only scratching at the surface of the problem, the best way of reducing cyclist
fatalities is to reduce cycle crashes

- motor vehicle drivers are to blame for most fatal crashes involving cyclists

- cyclist accident rates fall with increasing overall levels of cycling and rise as
cycling levels fall; the relationship is not linear, but it is consistent across large
numbers of countries

So, the best way of improving cyclist safety is to improve driving standards and to encourage more
people to cycle. The worst way to achieve that is to focus to excess on cycle helmets, for the
following reasons:

- it gives cyclists a false sense of security, so is dishonest - cycle helmets cannot protect
against the worst types of crashes, those where the cyclist is struck at speed by a car

- it reinforces the idea that road cycling is dangerous, which discourages people from cycling
on the roads, in turn making cycling on the roads more dangerous forthose who do so -
"positive feedback," in engineering terms

- it gives drivers the idea that the cyclist is engaging in a risky activity, when actually the
cyclist is doing something perfectly safe and benign but the driver is engaging in an activity
which kills thousands in the UK alone every year and is the largest single killer of children
in the developed world

- it gives weasel lawyers another stick with which to beat us.

The report, it seems to me, focuses mainly on the mechanistic effects of helmets, and ignores to a
large extent the much more profound social effects, as well as the causes of the crashes. Cause of
death: head injury is incomplete without the accompanying causation: driver error in the car which
hit the cyclist.

I think Sir Humphrey Appleby referred to this as a dog = cat solution: Something must be done, this
is something, therefore this must be done.

Guy
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In message <[email hidden]>, "Just zis Guy, you know?"
<[email hidden]> writes

Quoted message said:

Quoted message said:

1. Wearing a helmet increases the effective size of the head and therefore makes it more likely
that you'll hit something.

Quite. With a helmet I am nearly 1% taller. This is bound to exert a much greater influence on my
likelihood of hitting myhead than, say, the fact that I'm a few inches higher up because I'm
sitting on the saddle of a bike. Not. And given that I fall off, stopping 15mm from the ground is
not really a likely scenario, is it? I am not, after all, Arthur Dent.

Shouldn't we allow that it's not necessarily the height that is the issue? If the helmet adds, say,
10% to the radius then this equates to an increase in cross-sectional area of 21% thereby
substantially increasing the likelihood that the helmet/head unit will collide with a vehicle,
lamp-post or other piece of street furniture when involved in an incident. The helmet probably does
not increase the likelihood of the incident but may well increase the extent of the injury.
--
Michael MacClancy

In message <[email hidden]>, Michael MacClancy
<[email hidden]> writes

Quoted message said:

The helmet probably does not increase the likelihood of the incident but may well increase the
extent of the injury.

.... and the likelihood of an injury in the event of an incident.
--
Michael MacClancy

"Just zis Guy, you know?" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

On Thu, 17 Apr 2003 16:10:12 +0100, Paul Smith <[email hidden]> wrote:

roads.dft.gov.ukindex.htOpen ↗

m

Quoted message said:

The DfT of course has an agenda - they are now quite open about their desire to keep helmet
legislation on the agenda. The reason for this is simple, and consistent with many other aspects
of road "safety" policy: they have become accustomed to thinking the motor lobby way.

The motor lobby is wary to the point of paranoia about anybody considering accident reduction at
source as a means of improving road safety. Consider the possibilities this raises: raising the
standard of the driving test, reducing speed limits across the board, automated speed limiting,
harsher penalties for bad driving, even police activated remote engine immobilisers. So for over
half a century the road lobby has worked at setting the road "safety" agenda into a particular
mould: that of reducing the severity of consequences of poor driving, rather than addressing the
poor driving itself.

So, when considering cyclist safety the Government (and the road "safety" establishment) is
conditioned by decades of practice to consider that helmets are a valid safety measure, even
though they do absolutely nothing to stop accidents in the first place, and provide no proven
protection in crashes likely to be serious or fatal. Any complete analysis shows that:

- helmets are only scratching at the surface of the problem, the best way of reducing cyclist
fatalities is to reduce cycle crashes

- motor vehicle drivers are to blame for most fatal crashes involving cyclists

- cyclist accident rates fall with increasing overall levels of cycling and rise as cycling
levels fall; the relationship is not linear, but it is consistent across large numbers of
countries

So, the best way of improving cyclist safety is to improve driving standards and to encourage more
people to cycle. The worst way to achieve that is to focus to excess on cycle helmets, for the
following reasons:

- it gives cyclists a false sense of security, so is dishonest - cycle helmets cannot protect
against the worst types of crashes, those where the cyclist is struck at speed by a car

- it reinforces the idea that road cycling is dangerous, which discourages people from cycling
on the roads, in turn making cycling on the roads more dangerous forthose who do so -
"positive feedback," in engineering terms

- it gives drivers the idea that the cyclist is engaging in a risky activity, when actually
the cyclist is doing something perfectly safe and benign but the driver is engaging in an
activity which kills thousands in the UK alone every year and is the largest single killer
of children in the developed world

- it gives weasel lawyers another stick with which to beat us.

The report, it seems to me, focuses mainly on the mechanistic effects of helmets, and ignores to a
large extent the much more profound social effects, as well as the causes of the crashes. Cause of
death: head injury is incomplete without the accompanying causation: driver error in the car which
hit the cyclist.

I think Sir Humphrey Appleby referred to this as a dog = cat solution: Something must be done,
this is something, therefore this must be done.

Guy

Just zis Guy? You just said it all. Change it to "Just the Guy"?

Cheers

Rich

Quoted message said:

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Michael MacClancy said:

The assertions which seek to support this view include:

Yes, well-chosen words. "Assertions" and "seek." I commend you for your excellent use of
the language.

Quoted message said:

1. Wearing a helmet increases the effective size of the head and therefore makes it more likely
that you'll hit something.

Quite. With a helmet I am nearly 1% taller. This is bound to exert a much greater influence on my
likelihood of hitting myhead than, say, the fact that I'm a few inches higher up because I'm sitting
on the saddle of a bike. Not. And given that I fall off, stopping 15mm from the ground is not really
a likely scenario, is it? I am not, after all, Arthur Dent.

Quoted message said:

2. Wearing a helmet increases the effective radius of the head and therefore magnifies the
likelihood of torsional injuries caused by the head rotating in a crash.

I really have not seen any figures (credible or otherwise) to support this in the context of cycling
injuries. Remember, the torsional injuries which cause damage are where the head twists rapidly on
an axis, causing the two hemipheres of he brain to shear.

Quoted message said:

3. Cyclists who wear helmets are supposed, on average, to ride more recklessly than if they weren't
wearing helmets.

Or cyclists who ride recklessly (notably offroaders and BMXers) are more likely to wear helmets.

Quoted message said:

4. Helmets may protect against minor injuries but are ineffective against major injuries because
they aren't designed for these.

Is the absolute truth, and the real reason that any policy of promoting or even compelling helmet
use is ultimately dishonest.

Quoted message said:

But it's not all about banging heads on hard surfaces.

Here you are wrong: any helmet thread is *only* about banging head son hard surfaces :-D

Guy
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David Damerell said:

Quoted message said:

I've not seen any real evidence of torsional injuries in cyclists.

Quoted message said:

Broken necks do happen. Mind you, I don't think it's very significant, but I also don't think the
added protection against direct impact is very significant, and this is consistent with the
statistics.

I don't think broken necks would be much affected either way. Helmets are good for two things: they
reduce superficial injuries to the head in a crash, and they protect the skulls of children in
falls. But, see post in reply to the original.

Guy
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Quoted message said:

I've not seen any real evidence of torsional injuries in cyclists. I really do think it's a red
herring, like the extra height issue. A helmet increases my height on a bike by under 1% -
definitely insignificant.

I'm still not quite sure. What exactly are 'torsional injuries' and how do you spot them? I would
have thought you might expect some brain injuries - akin to shaken baby syndrome. But whether the
medics can tease them apart from other sorts of brain damage, I don't know.

Quoted message said:

The thing which the pro-lidders never quite manege to explain away is how non-wearers going over
the bars at speed (like my friend Albert, who face-planted at quite a rate recently) apparently
suffer pretty much the same levels of concussion and fractures, the only noticeable difference
seeming to be in soft-tissue injuries.

Quoted message said:

I'm quite content to wear a lid to save getting road rash on my head again, but I don't think it
will stop me being concussed or killed if I'm hit by another car.

I've just started wearing wrist protectors, though I'm almost certain they will never save my life.

Nice to hear from you again Guy, BTW,

Kit

Kit Wolf said:

I'm still not quite sure. What exactly are 'torsional injuries' and how do you spot them?

Let me know if you can't spot my version in one of the other bits of this thread - I'm repeating
myself rather on that one :-)

Quoted message said:

Nice to hear from you again Guy, BTW,

Thank you, it's good to be back. So much has changed! A helmet thread started by Mr Safety :-D

Guy
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Paul Smith said:

Your joke quite closely matches the subjective experience of many drivers involved in commonplace
accidents caused by inattention. Where a road user is inattentive it's quite "normal" for a
dangerous hazard to "suddenly appear".

The crucial difference being, of course, that it is dramatically less likely that a cyclist will be
in this brain-dead inattention state, since (a) the exercise contributes to greater alertness, (b)
you're not isolated form your surroundings and (c) inattention is a great way to end up dead, thanks
to the fact that large numbers of drivers /are/ in the aforementioned brain-dead inattention state.

Guy
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you know? said:

Quoted message said:

Your joke quite closely matches the subjective experience of many drivers involved in commonplace
accidents caused by inattention. Where a road user is inattentive it's quite "normal" for a
dangerous hazard to "suddenly appear".

Quoted message said:

The crucial difference being, of course, that it is dramatically less likely that a cyclist will
be in this brain-dead inattention state, since (a) the exercise contributes to greater alertness,
(b) you're not isolated form your surroundings and (c) inattention is a great way to end up dead,
thanks to the fact that large numbers of drivers /are/ in the aforementioned brain-dead
inattention state.

Speaking as someone who once cycled into a parked car, but has never driven into a parked car I
disbelieve your suggestion.

Many accidents, even probably most accidents, are due to inattention, and I have no reason to
believe that the proportions are unequal between car drivers and cyclists.

Show me evidence and I'll be pleased to reconsider.
--
Paul Smith Scotland, UK safespeed.org.uksafespeed.org.ukOpen ↗ please remove "XYZ" to reply by email speed
cameras cost lives

you know? said:

Kit Wolf said:

I'm still not quite sure. What exactly are 'torsional injuries' and how do you spot them?

Let me know if you can't spot my version in one of the other bits of this thread - I'm repeating
myself rather on that one :-)

As you said, lots has changed...

I did find it eventually, ta.

Kit

Quoted message said:

Quoted message said:

Nice to hear from you again Guy, BTW,

Thank you, it's good to be back. So much has changed! A helmet thread started by Mr Safety :-D

Guy
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Quoted message said:

Shouldn't we allow that it's not necessarily the height that is the issue? If the helmet adds, say,
10% to the radius then this equates to an increase in cross-sectional area of 21% thereby
substantially increasing the likelihood that the helmet/head unit will collide with a vehicle,
lamp-post or other piece of street furniture when involved in an incident. The helmet probably does
not increase the likelihood of the incident but may well increase the extent of the injury.

LOL - even adding 21% it's still a damn sight narrower than my [censored] - which as yet, han't collided
with vehicle or street furniture ;-)

Cheers, helen s

~~~~~~~~~~
Flush out that intestinal parasite and/or the waste product before sending a reply!

Any speeliong mistake$ aR the resiult of my cats sitting on the keyboaRRRDdd
~~~~~~~~~~

[email hidden] (wafflycathcsdirtycatlitter) wrote: ( LOL - even adding 21% it's still
a damn sight narrower than my [censored] - which as ) yet, han't collided with vehicle or street
furniture ;-)

Perhaps that's partly because you don't keep your [censored] sticking out to the front on the end of a
stalk when cycling. There are those who think that...

No. Definitely not.

Michael MacClancy said:

In message <[email hidden]>, "Just zis Guy, you know?"
<[email hidden]> writes

Quoted message said:

Quoted message said:

1. Wearing a helmet increases the effective size of the head and therefore makes it more likely
that you'll hit something.

Quite. With a helmet I am nearly 1% taller. This is bound to exert a much greater influence on my
likelihood of hitting myhead than, say, the fact that I'm a few inches higher up because I'm
sitting on the saddle of a bike. Not. And given that I fall off, stopping 15mm from the ground is
not really a likely scenario, is it? I am not, after all, Arthur Dent.

Quoted message said:

Shouldn't we allow that it's not necessarily the height that is the issue? If the helmet adds, say,
10% to the radius then this equates to an increase in cross-sectional area of 21% thereby
substantially increasing the likelihood that the helmet/head unit will collide with a vehicle,
lamp-post or other piece of street furniture when involved in an incident. The helmet probably does
not increase the likelihood of the incident but may well increase the extent of the injury.

Don't forget that you've done a great deal of learning about how to stop hitting your head; you duck
just enough to avoid branches; when falling over backwards you pull your head up just enough to
avoid floor impact, etc.. If you've ever tried wearing a helmet when climbing trees or rocks you
will have noticed how annoyingly often you clunk it into things. It's not just the increased
probability of the extra size, it's that your entire reperory of head-bang-avoidance reflexes are
miscalibrated once you don a helmet.
--
Chris Malcolm [email hidden] +44 (0)131 650 3085 School of Artificial Intelligence, Division of
Informatics Edinburgh University, 5 Forrest Hill, Edinburgh, EH1 2QL, UK
[dai.ed.ac.ukcamOpen ↗ ] DoD #205

In message <[email hidden]>, Chris Malcolm <[email hidden]> writes

Quoted message said:

Don't forget that you've done a great deal of learning about how to stop hitting your head; you
duck just enough to avoid branches; when falling over backwards you pull your head up just enough
to avoid floor impact, etc.. If you've ever tried wearing a helmet when climbing trees or rocks you
will have noticed how annoyingly often you clunk it into things. It's not just the increased
probability of the extra size, it's that your entire reperory of head-bang-avoidance reflexes are
miscalibrated once you don a helmet.
--

Quite. Further probable examples of the effect of helmets on head size are the reported
instances of children who strangle themselves on the helmet straps when their helmets become
inadvertently trapped in climbing frames. It seems that their bodies will go through apertures
that the helmets won't.
--
Michael MacClancy

"Richard Burton" <[email hidden]> wrote in message
news:<[email hidden]>...

Quoted message said:

Just zis Guy? You just said it all. Change it to "Just the Guy"?

I too agree with every word of Guy's message, but don't see the need to quote it in its entirety.

--
Dave...

Paul Smith said:

W K said:

Quoted message said:

A rather more plausible risk compensation mechanism is that when perceived risk is lower less
attention is paid to the task at hand.

Quoted message said:

Quoted message said:

Since many accidents are avoided by a mechanism of early perception and planned avoidance, it
follows that less attention can easily lead to an increase in accidents.

Quoted message said:

You really haven't got a clue about what it feels like to ride a bike have you?

You what?

Perhaps you would like to post your analysis or experience of risk compensation mechanisms instead
of resorting to foolish jibes.

And this reply from a hypocrite who on uk.tosspot when confronted with a more intelligent reasoning
on safety matters than his own, by someone he thought did not drive, ended nearly every message
with: 'You don't drive do you'.

Sheesh. So....

You don't cycle do you Smith.

John B

Just zis Guy said:

So, when considering cyclist safety the Government (and the road "safety" establishment) is
conditioned by decades of practice to consider that helmets are a valid safety measure,

Especially since helmets, unlike accident prevention measures, would be paid for by the cyclist, not
the State.
--
David Damerell <[email hidden]> Distortion Field!