Helmets reduce bicycle-related head and facial injuries

Derek C wrote:

You are much more likely to head butt the tarmac, pavement, ground, or
vehicle in the course of a cycle accident than you would in a glider
accident.


Seems head injuries for glider pilots are not unknown by any means:

http://news.bbc.co.uk/1/hi/england/2794833.stm
http://www.dailymail.co.uk/news/arti...r-crashes.html
http://www.gremline.com/index_files/page0043.htm

--
Tony

" I would never die for my beliefs because I might be wrong."
Bertrand Russell

In article ,
Phil W Lee phil(at)lee-family(dot)me(dot)uk wrote:

Sorry, 0/10 for arithmetic. There are about 15,000, 70% of which
cycle.

Is it really as low as 70%?
I'd have estimated at least 95%, based partly on the fact that I've
never actually met an undergraduate at Cambridge who didn't cycle, so
4% is "benefit of the doubt" allied to the fact that I know of the
existence of a few students with disabilities (although I don't
actually know any) which probably account for less than 1%.

It was a wild guess, but probably fairly accurate.

How on earth do non-cycling students get around?
I know those with disabilities would be allowed a car, but that's a
tiny number.

It may surprise you, but humans used to travel fair distances before
bicycles were invented, using a method of locomotion known as
"walking". Some still do.


Regards,
Nick Maclaren.

On Jun 17, 11:24*pm, Tony Raven wrote:
Derek C wrote:

You are much more likely to head butt the tarmac, pavement, ground, or
vehicle in the course of a cycle accident than *you would in a glider
accident.

Seems head injuries for glider pilots are not unknown by any means:

http://news.bbc.co.uk/1/hi/england/2...s/page0043.htm

--
Two of these reports are the same accident. The other one (ASW20
glider) was a cartwheel from a winch launch, where the glider would
tend to crash upside down, a very rare type of accident. These are the
exceptions rather than the rule. In normal flight it is more important
to be able to fully turn your head to keep a good lookout to avoid mid-
air collisions. Many higher performance gliders have very limited
headroom, so you wouldn't be able to fit a helmet in and/or be able to
turn your head properly. This is another example of a psycholist
saying that if you wear a helmet on a bike, you also have to wear it
for other totally inappropriate activities!

Derek C

On Jun 17, 11:42*pm, wrote:
In article ,
Phil W Lee *phil(at)lee-family(dot)me(dot)uk wrote:



Sorry, 0/10 for arithmetic. *There are about 15,000, 70% of which
cycle.

Is it really as low as 70%?
I'd have estimated at least 95%, based partly on the fact that I've
never actually met an undergraduate at Cambridge who didn't cycle, so
4% is "benefit of the doubt" allied to the fact that I know of the
existence of a few students with disabilities (although I don't
actually know any) which probably account for less than 1%.

It was a wild guess, but probably fairly accurate.

How on earth do non-cycling students get around?
I know those with disabilities would be allowed a car, but that's a
tiny number.

It may surprise you, but humans used to travel fair distances before
bicycles were invented, using a method of locomotion known as
"walking". *Some still do.

Regards,
Nick Maclaren.

Even if 95% of Cambridge students cycle, the gliding death rate
applied to them would still only be 1.4 fatalities per annum. Gliding
is a risk sport, but it's much safer than motorcycling and horse
riding.

Derek C

On Thu, 17 Jun 2010 14:41:18 -0700 (PDT), Derek C wrote:
On Jun 17, 6:47*pm, Ian Smith wrote:
On Thu, 17 Jun 2010, Derek C wrote:
*On Jun 17, 1:35*pm, Ian Smith wrote:
On Wed, 16 Jun 2010 10:48:40 -0700 (PDT), Derek C wrote:
*I think that cycle helmets should have a thin hard shell, something
*like motorcycle helmets, so that they slide better. Would that remove
*your objection?

A thin hard shell would not necessarily slide better. *What material do
you propose to make it from? *Most existing helmets have a very thin
shell, and most slide worse than hair and scalp.

*Motorcycle helmets are designed to slide and are made from composities
*or molded ABS or polycarbonate. see:

*http://www.motorcyclistonline.com/ge...lmet_review/in...

Err, no, that link does not say that motorcycle helmets are designed
to slide better than hair and scalp. *It doesn't even say they are
designed to slide to any performance criterion, only that they are
designed to resist the effects of sliding (ie abrasion). *Try again.

I would imagine that molded polycarbonate would slide very well. It's
the same stuff as they use for unbreakable headlight lenses in modern
cars, and it's very hard and smooth

So you agree your statement "motorcycle helmets are designed to slide"
was rubbish, thank you.

Your proposal for what to make the shell of helmets from is
polycarbonate. You "imagine" that this will slide well, but have no
basis for the opinion other than your imagination. Polycarbonate is
not a particularly hard material, despite your assertion.


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On Jun 18, 6:19*am, Ian Smith wrote:
On Thu, 17 Jun 2010 14:41:18 -0700 (PDT), Derek C wrote:
*On Jun 17, 6:47*pm, Ian Smith wrote:
On Thu, 17 Jun 2010, Derek C wrote:
*On Jun 17, 1:35*pm, Ian Smith wrote:
On Wed, 16 Jun 2010 10:48:40 -0700 (PDT), Derek C wrote:
*I think that cycle helmets should have a thin hard shell, something
*like motorcycle helmets, so that they slide better. Would that remove
*your objection?

A thin hard shell would not necessarily slide better. *What material do
you propose to make it from? *Most existing helmets have a very thin
shell, and most slide worse than hair and scalp.

*Motorcycle helmets are designed to slide and are made from composities
*or molded ABS or polycarbonate. see:

*http://www.motorcyclistonline.com/ge...lmet_review/in...

Err, no, that link does not say that motorcycle helmets are designed
to slide better than hair and scalp. *It doesn't even say they are
designed to slide to any performance criterion, only that they are
designed to resist the effects of sliding (ie abrasion). *Try again..

*I would imagine that molded polycarbonate would slide very well. It's
*the same stuff as they use for unbreakable headlight lenses in modern
*cars, and it's very hard and smooth

So you agree your statement "motorcycle helmets are designed to slide"
was rubbish, thank you.

Your proposal for what to make the shell of helmets from is
polycarbonate. *You "imagine" that this will slide well, but have no
basis for the opinion other than your imagination. *Polycarbonate is
not a particularly hard material, despite your assertion.

The hard shell on motorcycle helmets is there to resist intrusions
from sharp objects, to slide and to protect your head against
abrasion. Remember that motorcyclists can come off at very high speeds
and can slide for some distance: If I may quote from:

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


"A motorcycle helmet has two major parts: the outer shell and the
energy-absorbing inner liner. The inner lining is made of expanded
polystyrene or EPS, the same stuff used in beer coolers, foam coffee
cups, and packing material. Outer shells come in two basic flavors: a
resin/fiber composite, such as fiberglass, carbon fiber and Kevlar, or
a molded thermoplastic such as ABS or polycarbonate, the same basic
stuff used in face shields and F-16 canopies.

The shell is there for a number of reasons. First, it's supposed to
protect against pointy things trying to penetrate the EPS—though that
almost never happens in a real accident. Second, the shell protects
against abrasion, which is a good thing when you're sliding into the
chicane at Daytona. Third, it gives Troy Lee a nice, smooth surface to
paint dragons on. Riders—and helmet marketers—pay a lot of attention
to the outer shell and its material. But the part of the helmet that
absorbs most of the energy in a crash is actually the inner liner."

Please note that cycle helmets are made of the same EPS material as
the liners in m/c helmets, and that is the part of them that does the
energy absorption in a crash.

Derek C

Derek C wrote:
This is another example of
a psycholist saying that if you wear a helmet on a bike, you also
have to wear it for other totally inappropriate activities!


No, its an example of cyclists saying that helmets are no more
appropriate for cycling than other activities of similar risk levels,
especially as there is no demonstrated safety benefit of cycling helmets.

--
Tony

" I would never die for my beliefs because I might be wrong."
Bertrand Russell

In article , Phil W Lee wrote:
considered Thu, 17 Jun 2010 16:08:58 +0100 (BST) the
perfect time to write:

Sorry, 0/10 for arithmetic. There are about 15,000, 70% of which
cycle.

Is it really as low as 70%?
I'd have estimated at least 95%, based partly on the fact that I've
never actually met an undergraduate at Cambridge who didn't cycle

I knew a few.


How on earth do non-cycling students get around?

They walked.

In article ,
Phil W Lee phil(at)lee-family(dot)me(dot)uk wrote:

How on earth do non-cycling students get around?
I know those with disabilities would be allowed a car, but that's a
tiny number.

It may surprise you, but humans used to travel fair distances before
bicycles were invented, using a method of locomotion known as
"walking". Some still do.

I just find it surprising that anyone can manage time wise, given the
geographical distribution of the university and the lecture schedules.

If the students have back-to-back lectures on significantly separated
sites, they can't get between them anyway, and the scheduling is
designed to avoid that. If they don't, there is no problem.


Regards,
Nick Maclaren.

wrote:
In article ,
Phil W Lee phil(at)lee-family(dot)me(dot)uk wrote:

I just find it surprising that anyone can manage time wise, given the
geographical distribution of the university and the lecture schedules.

If the students have back-to-back lectures on significantly separated
sites, they can't get between them anyway, and the scheduling is
designed to avoid that. If they don't, there is no problem.


Indeed. One of my daughters didn't cycle for her entire first year with
rooms in Emma, lectures on the Downing Site, entertainment across the
road, Sainsbury's just up the road and a short walk to the boathouse.
The other cycled from the beginning with rooms in Jesus and lectures
down in Engineering on Lensfield Road being somewhat further apart
especially if you got up late.

--
Tony

" I would never die for my beliefs because I might be wrong."
Bertrand Russell