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PostPosted: Fri Jul 29, 2005 3:55 pm 
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Nico wrote:
My first helmet was custom made, as they all gave me a headache.
I put on two neoprene diving hoodies and had a friend laminate resin and glass over my nut. It got pretty hot underneath for a while, and I sat next to my compressor for some fresh air to breath.
Now my son is using it, as I have tried the protech ace wake which fits like a glove.



Thanks for your input Nico. Good fit and comfort are very important in a helmet. I saw a few very poorly fitting helmets at a recent competition. The helmets might put the riders more at risk of injury because of the poor fit with a hard impact against water than otherwise.
Nico wrote:
Here almost no one wears a helmet, they all feel it will not hapen to them.
Nico


I recently learned that this may be a more widespread reason that "it makes me look stupid" long touted in the past. That is denying anything bad will ever happen. I expect that I could get slammed badly anytime I have a kite up. Of course the probability varies substantially with conditions. You take reasonable precautions and get on with it.

Why do some folks feel otherwise about the hazards? I am having trouble understanding this.

FKA, Inc.
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PostPosted: Sat Jul 30, 2005 1:12 pm 
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RickI wrote:
Nico wrote:
Here almost no one wears a helmet, they all feel it will not hapen to them.
Nico
I recently learned that this may be a more widespread reason that "it makes me look stupid" long touted in the past. That is denying anything bad will ever happen. I expect that I could get slammed badly anytime I have a kite up. Of course the probability varies substantially with conditions. You take reasonable precautions and get on with it.

Why do some folks feel otherwise about the hazards? I am having trouble understanding this.

another possibility... location.

Most accidents happen at launching, or when conditions change when you are on the water.
What are the hazzards when riding in deep water ?
Go for a big jump and get it wrong on landing, more often than not you would hit the water feet/board first, not with your head. ?
Other hazzard would be getting hit by your board, again if you loose your board in a jump it will be on the water before you are and more than likely be upwind ?

There is one thing to remember... Which many don't realise.
water can be as hard as concrete if you land flat.

Real Hazzards are when you are in shallow water - less than 10ft deep, where it would be very easy to hit the sea bed/ground following a high jump then get dragged onto/up the beach or rocks due to broken bones etc...


Rick - Would be interested to know the breakdown of the figures -
How many Head injuries on the water ?
Number of head injuries compared to ankle, knee, leg injuries when the accident happened on the water ?

Do more head injuries happen when getting dragged following a failed/bad launch ?


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PostPosted: Sun Jul 31, 2005 3:37 am 
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RickI wrote:
A man fataly broke his neck recently in fairly light winds, with a small kite with NO helmet to add to the load on his spine. I would say understanding the realities of helmet drag is pretty important. You want as LITTLE drag, added mass/weight as possible to minimize a potential pain in the neck! So, no unncessary surface area, extra surfaces to cause drag or unncessary weight.


Hemets have never been shown to increase the likelihood of a neck injury. There have been retrospective studies on bicyclists, motorcyclists and other helmet wearers to prove this. They also showed a non-helmeted riders had a 300% higher fatality rate. The whole neck injury thing comes from people who want an excuse not to wear a helmet.

Of course to throw another wrench into the works: there was a single small study that stated helmeted skiers (snow) were more likely to be injured because the helmet made them feel safe and they would ride beyond their skill level.

Honestly, at this point I don't wear a brain bucket on the water. I do wear one when snowkiting or KGBoarding. In fact 2 years ago I was coming in from a snowkite session when a sudden windshear took the kite in a different direction causing me to slam the back of my head against the ice. It split my helmet and the foam inside was in 4 pieces. Me? I had a whopping headache and a reason to buy a new helmet...the price was no longer an issue! :)


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PostPosted: Sun Jul 31, 2005 5:00 am 
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spidermedic wrote:
RickI wrote:
A man fataly broke his neck recently in fairly light winds, with a small kite with NO helmet to add to the load on his spine. I would say understanding the realities of helmet drag is pretty important. You want as LITTLE drag, added mass/weight as possible to minimize a potential pain in the neck! So, no unncessary surface area, extra surfaces to cause drag or unncessary weight.


Hemets have never been shown to increase the likelihood of a neck injury.


Yes, they have unfortunately. That is where the term "bucketing"* came from. I am not aware of drag related injury but it really isn't much of a stretch to imagine cervical problems related to drag and added water weight with higher speed impacts. Part of this reasoning comes from impressions formed from using a helmet for five years in all sorts of conditions while kiteboarding. No neck problems despite some very fast wipeouts. Then again, I avoid helmets with lots of drag and bucketing potential, fit well, don't have any preexisting neck sensitivity, etc..

* One definition of bucketing appears at: http://www.ntsb.gov/Recs/letters/1998/M98_85_86.pdf

FKA, Inc.

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Last edited by RickI on Sun Jul 31, 2005 12:58 pm, edited 1 time in total.

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PostPosted: Sun Jul 31, 2005 5:16 am 
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mx5alan wrote:
Rick - Would be interested to know the breakdown of the figures -
How many Head injuries on the water ?
Number of head injuries compared to ankle, knee, leg injuries when the accident happened on the water ?

Do more head injuries happen when getting dragged following a failed/bad launch ?


The majority of head injuries that I have heard about have happened on or near land. In some cases boat collisions have been involved. Most of our fatal accidents involved severe head injury.

Some of these guys were on land when things went bad, some were in standing in the water while some were even riding.

I believe that a fatal offshore accident in Holland MAY have possibly been avoided if a good helmet had been employed. This is speculation of course as we will never likely know. At any rate the rider hit the water hard after doing an overpowered downwind turn in some gusting wind. He slammed hard into a steep wave, his kite hit the water and then self relaunched. He was lofted very fast over the water about 30 m until he hit water again very hard. He was very experienced but was not seen to have moved after the first impact. He may have been knocked unconscious at the time of the first impact and possibly suffered the fatal injury on the second much harder collision against water. A good well fitting helmet, may be able to reduce impact effects against water as well.

The hazards of the land are there for most of us that launch and land off the shore and even for guys that use boats. Kites pull harder in gusts and hard objects are not fun to be dragged or lofted into. Gear up with some reasonable protection or blow it off while awaiting more injuries to create a more convincing basis. Choices.

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PostPosted: Sun Jul 31, 2005 3:50 pm 
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RickI wrote:
spidermedic wrote:
Hemets have never been shown to increase the likelihood of a neck injury.


Yes, they have unfortunately. That is where the term "bucketing"* came from. I am not aware of drag related injury but it really isn't much of a stretch to imagine cervical problems related to drag and added water weight with higher speed impacts. Part of this reasoning comes from impressions formed from using a helmet for five years in all sorts of conditions while kiteboarding. No neck problems despite some very fast wipeouts. Then again, I avoid helmets with lots of drag and bucketing potential, fit well, don't have any preexisting neck sensitivity, etc..

* One definition of bucketing appears at: http://www.ntsb.gov/Recs/letters/1998/M98_85_86.pdf


Rick,
I looked at the article, thanks.
I'll offer a couple of comments: There is only one study quoted related to neck injuries and it appears to be completely theoretical. I googled and couldn't find the actual study, but the author doesn't appear to have a medical background. To me, it mimics the early assumptions that the weight of a helmet would cause more loading on motorcyclists and increase the incidence of neck injuries. Makes sense in theory, but doesn't play out in reality.
Second, the paper reports 563 injuries, 232 head injuries and 19 spinal injurues. The discussion of spinal injuries is focused on compression fractures from jumping. These usually occur in the lumbar region and, in this paper, the coccyx (tailbone) from smacking the seat of the PWC. There was no specific mention of C-spine injuries.

Don't get me wrong, I don't think it's unreasonable to look for a helmet that won't catch water. But, with a minimal number of reported spinal injuries and few (if any) neck injuries, I don't think this is as much of as concern...protecting your squash should be the main priority.

Kudos to you for starting the thread :thumb:

BTW: If you've seen any medical studies, please let me know as I'd like to see them. I couldn't find any on PubMed, but here are a other few abtracts to show you where I'm getting my info from.

http://www.ncbi.nlm.nih.gov/entrez/quer ... query_hl=6

http://www.ncbi.nlm.nih.gov/entrez/quer ... query_hl=6

http://www.ncbi.nlm.nih.gov/entrez/quer ... query_hl=6


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PostPosted: Sun Jul 31, 2005 4:28 pm 
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I did some searching too and failed to find much in the way of medical studies on the subject. I believe the term was coined to describe what happened to a coastguardsman who fell out of a rib boat traveling at high speed with a motorcycle-like helmet on. I believe it was a fatal accident. There may have been others perhaps in boat racing/hydrofoils. I believe it is addressed in the ASTM standard under development, WK3458 Standard Specification for Helmets for Whitewater Sports. The term also shows up in some wakeboarding accounts. Some manufacturers such as Gath are sensitive to the question of bucketing and promote the lack of that tendency as a design attribute.

I believe you must be in water for "bucketing" to occur. Land accidents although related lack the critical drag elements of bucketing. The helmet acts like a "bucket" IF the securing system slips or if the helmet fits poorly or if the design is prone to filling up with water or drains poorly. The drag and added mass load up the cervical area through the fastening system. So, to the best of my knowledge, "bucketing" is an accepted hazard in some water activities and efforts have been expended by some to minimize the risk.

By virtue of poor helmet fit and loose fastenings, this person could be said to be at risk of bucketing during a high speed impact against water:

Image

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Last edited by RickI on Sun Jul 31, 2005 5:12 pm, edited 1 time in total.

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PostPosted: Sun Jul 31, 2005 5:01 pm 
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I found a couple of related references, one of which calls "bucketing" the "scoop effect" at:

http://ribworld.com/forum/showthread.php?p=14406

I was able to find the Institute of Naval Medicine report referenced in the Gecko post at:

http://www.geocomms.com/downloads/GeoCo ... 0Study.pdf

It is worth a read as it goes into some of what we have been talking about. I used to think "bucketing" didn't apply all that well to kiteboarding given our lower speed of impact (less than 40 to 50 kts. as a rule) unlike the guys falling out of speeding boats who seemed to be the focus in the past. Ultimately the problem is loading up the cervical area with excess tension, torsion and/or dynamic impact. How you get there can vary, through bucketing, excess weight or I also feel through excess drag. The quote listed below backs up drag related problems. Neck fracture isn't required for this to cause a problem. Neck inflammation can be enough of an annoying problem all by itself. The following is from the above report.

"Charrier & Oakley (1996) used a lumped parameter model to assess the risks of wearing a safety helmet to occupants of RIBs. They considered that the highest risk to personnel in RIBS was from limb or head impact with the boat. However, there was some anecdotal evidence of people being ejected from a RIB sustaining neck injuries while wearing a helmet. The mechanism believed to be responsible was the lip of the helmet contacting the water in such an attitude that it acted as a scoop,
and the consequent decelerative forces are transmitted to the neck resulting in injury. This will be called the scoop effect. Their initial model indicated a linear relationship between the thickness of the helmet and the forces transmitted to the critical neck structures."

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PostPosted: Sun Jul 31, 2005 5:52 pm 
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This impact-with-water business is a giant red herring. In the context of kiteboarding, helmets are to protect your head from solid objects like trees, rocks and your board. They will not help prevent head injuries caused by hitting water, but that doesn't matter because you will never hear of a kiteboarding head injury (concussion, skull fracture) caused by an impact solely with water.

Impacts solely with water (no impact with board or terrain) may in some cases cause internal injury or even spinal injury if you hit the water really hard or at a weird attitude, but the effect of a helmet on such an injury is so insignificant that we will probably never hear of such a circumstance. So don't get hung up on this "bucketing" business. It's like saying you shouldn't wear a seatbelt in your car because some day your life might be saved by being thrown clear of the car - possible maybe, but a seriously misguided application of probabability.


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PostPosted: Sun Jul 31, 2005 6:13 pm 
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They will not help prevent head injuries caused by hitting water, but that doesn't matter because you will never hear of a kiteboarding head injury (concussion, skull fracture) caused by an impact solely with water.

I agree, if you hit hard enough to cause a concussion or skull fracture you may have other problems to worry about. Hitting that hard against water isn't particularly likely as you say.

The point was in possibly avoiding LOSS OF CONSCIOUSNESS using a helmet and thereby being in a position to try to get things under control. You don't want to be asleep with a powered up, out of control kite. There may be precedent for this type of accident. The main purpose for helmets is protecting against hard objects however as so many accidents in the past have underscored.


None of this is stated to support NOT USING A HELMET while kiteboarding.

It was posted to support the contention of using a light, low drag, well secured helmet.

Helmets have been recommended for use while kiteboarding for years. I won't kiteboard without one.

The use of helmets with low drag, weight and bucketing potential has also be recommended for years. Nothing has change at this end.


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