On 1/18/2020 11:21 PM, John B. wrote:
On Sat, 18 Jan 2020 19:07:56 -0800 (PST), Frank Krygowski
wrote:

On Saturday, January 18, 2020 at 8:38:25 PM UTC-5, Sir Ridesalot wrote:
On Saturday, 18 January 2020 19:31:22 UTC-5, Jeff Liebermann wrote:
On Thu, 16 Jan 2020 12:05:06 -0500, Radey Shouman
wrote:

Girl, 4, died after bike helmet got caught on branch:

https://www.bbc.com/news/uk-england-...shire-51139789

She wasn't riding her bike at the time, but, being four years old, she
probably wasn't able to remove her own helmet.

Perhaps we should all try a simple experiment. Throw a rope over an
overhead tree branch or roof beam. Attach the other end of the rope
to your bicycle helmet. Take up the rope slack by bending your knees.
No need to lift your feed off the ground as you're likely to strangle
yourself, break your neck, or hyperextend some muscles.

While the chin strap is under tension, try to release the chin strap
clip (also known as a "quick release buckle").
https://www.google.com/search?q=quick+release+buckle&tbm=isch
I just tried it on my (Giro Indicator G151X) helmet, with only a few
kg of tension, and couldn't release the chin strap (quickly or
otherwise). The harpoon shaped clips are designed to hold under
tension.

The buckle on my spare helmet did something unexpected. If I only
pushed one of the two buttons on each side, the quick release would
jam. Squeezing the remaining button did not release the buckle. In
order to release it, I had to push the buckle back together, and then
push BOTH buttons at the same time, in order to convince the buckle to
release. I doubt if a four year old could manage that. My Giro
helmet didn't jam, but did require quite a bit of force to squeeze one
or both buttons to release the buckle.

In my never humble opinion, it would not be difficult to redesign the
common "quick release buckle" so that it would release under tension
or possibly when an added release cord and D-ring is pulled.



--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

The trick would be designing the release so that it stays attached in an accident yet releases if the pressure on it stays beyond a certain time.

I have a friend who was pulled off his MTB whilst riding off-road, when a branch snagged in one of his helmet vent holes. Fortunately, other than being a bit stunned o=upon impact with the trail he was okay.

I wonder how many injuries are caused by a helmet strap not releasing when the helmet is snagged by something? I think it would be filed under "freak accident".

A very good friend of mine was once a rather rabid helmet promoter.
She actually worked in a position where helmet promotion was one of
her main duties. This was back in the early 1990s, not long after the
terribly constructed (or perhaps dishonest) Thompson & Rivara paper
had been published.

She said to me "85%, Frank! 85% benefit! And it's so simple!"

Turns out the benefit is not anywhere close to 85%. And the more you
study the details, the more you realize it's not simple at all.

- Frank Krygowski

I came across something the other day that apparently that referenced
several sources as follows:
https://www.cyclehelmets.org/1012.html

Specific research into fatalities in Sheffield, UK (Kennedy, 1996) has
shown that even if head injuries were eliminated completely, at least
50% of cyclist deaths would still occur. Most fatalities involve
multiple injuries and head injury is not the sole cause of death. The
experience of a solicitor specialising in cyclist injuries (BHRF,
1173) supports the view that deaths solely due to head injury are
unusual.

A study of cyclist crashes in Brisbane, Australia concluded that
helmets would prevent very few fatalities (Corner, Whitney, O'Rourke
and Morgan, 1987). All deaths were caused through collisions between a
bicycle and a motor vehicle. For 13 of the 14 cyclists who died, there
was no indication that a helmet might have made any difference.

In inner London, 58% of cyclist fatalities were caused by collisions
with heavy good vehicles, as were 30% of those in outer London
(Gilbert and McCarthy,1994). The idea that a lightweight polystyrene
helmet could be of significant benefit in such circumstances is
unrealistic...

There are a number of other references in the article, one of which
titled "Cyclist injury data before and after helmet law in Western
Australia" demonstrating that hospital admissions, referenced to the
number of cyclists, actually rose with the advent of the mandantory
helmet law.

There's plenty of data showing that the massive uptake in bike helmets
hasn't caused a detectable reduction in fatalities. That means that that
thousands of people who were promoting helmets as absolutely necessary
life savers were wrong. It also means that the vast majority of the
countless "my helmet saved my life" stories must be wrong. They're not
dishonest; they're just wrong.

There's also data showing that bike helmets haven't reduced cyclist's
traumatic brain injuries. Bicyclist concussions have gone up, way up,
over the last decade just as helmet use continued to rise.

But that hasn't stopped the helmet promotion. Even on this group, we've
had people who used to say helmets saved lives or prevent brain
injuries. Now they piously say they wear a helmet only to prevent minor
injuries.

But they never ride without it.


--
- Frank Krygowski