Do you wear a helmet on your commute?

[srw]

I take it all back. We're not all capable of logical thought. Linford has just proved me wrong.

 

[Red Light]

Bluntly, User, and I am sorry if I've got this very wrong, I can't help but feel that you're trying to deliberately misrepresent the engineering meaning of testing by trying to imply that there is some safety factor that you can rely upon. There isn't.

If you talk to the people who do the helmet tests they'll tell you quite a few struggle to even pass the tests. And its not just the cheap ones but also many of the very expensive ones. Its one of the reason Snell got downgraded and then dropped in favour of the even weaker EN standard.

 

[ufkacbln]

Cunobelin

This is not entirely true is it?

Further misrepresentation of my views and not helpful at all to the discussion

I am quite happy for you to explain your position......

Do you think that decisions such as whether you wear a helmet should be based on evidence or personal opinion?

It is of course possible that I have misunderstood the statements where you have made it clear about the importance you place on evidence:

I dont need to prove to myself I should wear a helmet or not to wear a helmet, if i'm ignorant on this point then so be it. shame you have to live with the burden of having to have evidence before you can form an observation or opinion of your own

I cannot think how depressing life would be for somebody to worried to hold an opinion without having first to read up on in depth evidence and data, I am glad I am free from this burden you obvious carry.

"I have not read any of the evidence, nor do I wish to do so, yet despite this my opinion is that you should all wear helmets and I am going to support your decision to do so whether you want to or not"

I do not need to study evidence before deciding to wear or not wear a helmet

 

[ufkacbln]

Marry me, TC!!!

Tart!

 

[Boris Bajic]

Where did you get that idea from? Its about "Do you wear a helmet on your commute?" Do people not commute on foot? [/quote]

This thread is raising whatever that thing is that gets raised when someone like Usain Bolt runs jolly fast and someone on the telly says that he's raising the something....

Anyway, whatever that something is, this thread is raising it. Well done all. Is it a bar or maybe a threshold?

But on the matter of commuting by foot, I have a feeling that few people do so.

my (limited) understanding suggests that commuting to work suggests a journe longer than one might regularly consider doing on foot.

I may be terribly wrong on this, but even if I am I will tell myself I am not. It was ever so.

 

[david k]

Do you think that decisions such as whether you wear a helmet should be based on evidence or personal opinion?
:

As its an individuals choice, its up to you whether you wish to study evidence or use you own opinions when deciding whether to wear a helmet or not.

Do you believe in personal choice or must an individual study in depth analysis before deciding to wear a helmet or not?

 

[StuAff]

As its an individuals choice, its up to you whether you wish to study evidence or use you own opinions when deciding whether to wear a helmet or not.

Do you believe in personal choice or must an individual study in depth analysis before deciding to wear a helmet or not?

Again with this stuff........

 

[StuartG]

One also has to be careful of distinguishing between the results of exceeding the design limit. If you have a concrete bar and you are sitting on it - then all is fine until it fails. You then have zero support and probably a terminal experience. It doesn't matter what the limit is - only that it has been exceeded and failed. Catastrophic failure.

If instead you were sitting behind the crumple zone of a car then the collapse is progressive. You may be fine up to the design limit - but even after that you benefit from the energy dissipation. You are still in a more survivable position than if there had been no crumple zone. Helmets AFAIK work on the crumple principle. Progressive failure.

One can argue that current helmets offer very poor crumple capability and it may be of a different magnitude to otherwise fatal or life changing fractures. In other words the effect may be small. But a cut off at 12 mph? Sounds dodgy. And don't forget the forces to dissipate will have as much to do with the angle of attack as to the velocity.

 

[srw]

Do you think that decisions such as whether you wear a helmet should be based on evidence or personal opinion?

Preferably both - until we're all autobot droids programmed by the flame-haired Brooksmaster from the planet Tone.

 

[david k]

Again with this stuff........

I know, I know

 

[Norm]

If instead you were sitting behind the crumple zone of a car then the collapse is progressive. You may be fine up to the design limit - but even after that you benefit from the energy dissipation. You are still in a more survivable position than if there had been no crumple zone. Helmets AFAIK work on the crumple principle. Progressive failure.

Yes, they should, but going with your concrete bar analogy, when the design limit of a helmet is exceeded, it is possible that the outer shell will fail so the polystyrene inner will snap rather than crumple. It will, IMO, have absorbed some of the energy but, without the plastic shell to support it, I think that this will be much reduced from the 50J figure quoted above.

Tart!

Whilst this is true, I doubt that it would rank against the news that Prince Harry has a todger to make the front pages.

 

[mcshroom]

One also has to be careful of distinguishing between the results of exceeding the design limit. If you have a concrete bar and you are sitting on it - then all is fine until it fails. You then have zero support and probably a terminal experience. It doesn't matter what the limit is - only that it has been exceeded and failed. Catastrophic failure.

If instead you were sitting behind the crumple zone of a car then the collapse is progressive. You may be fine up to the design limit - but even after that you benefit from the energy dissipation. You are still in a more survivable position than if there had been no crumple zone. Helmets AFAIK work on the crumple principle. Progressive failure.

One can argue that current helmets offer very poor crumple capability and it may be of a different magnitude to otherwise fatal or life changing fractures. In other words the effect may be small. But a cut off at 12 mph? Sounds dodgy. And don't forget the forces to dissipate will have as much to do with the angle of attack as to the velocity.

All well and good, and makes sense, but then you need to investigate the failure mode of a helmet. If you strike expanded polystyrene with a force above a certain level, you will cause the polystyrene to fracture, thus you have a catastophic failure.

In the case of fracture (at least when I cracked one coming off on diesel and others I've seen pictured) there is very little compression of the helmet shell, as the crack provides a much easier release for the energy involved in the impact, and thus the 'crumple zone' of the helmet shell is effectively bypassed.

What you are looking for in an accident situation is for the energy of the impact to be dissipated as slowly as possible. There will be a very small slowing effect due to the forming of the crack, but unfortunately nothing like as much of a dissipation as a helmet below this fracture threshold would produce.

 

[Wobblers]

I know of one young lad dealt with by a colleague got the end of his BMX bars through his skull. Beyond that, if you want to know you'll have to go out and count them yourself.

And a helmet would have protected him exactly how?

 

[Wobblers]

[QUOTE 2001353, member: 45"]No I'm not. What I'm saying is that helmets are tested by dropping weights on them at certain speeds as I understand. This has been misrepresented to suggest that they're not effective in impacts where the prior travelling speed of the bicycle is above that speed.

I'm under no illusion about the limits to helmets.

And that when RL says "about" what he means is that he's exaggerating figures to suit his position.[/quote]

You're quite right, they are indeed tested in this fashion. A crucial point is that you cannot have any expectation that they will offer any protection in impacts greater than what they are designed for. My concern is that anyone who is not familiar with the materials science or testing methods may incorrectly assume that a helmet to the relevant EN standard can be expected to offer greater protection than it is designed for. That is not correct.

You're correct in saying that the suggestion that a helmet will offer no protection at speed is misrepresentative, I can see where you're coming from and I have to agree. But again, the science equally means that you cannot assume that you will get any protection in such circumstances. You might. Or you might not. It depends on many variables. You've never suggested otherwise, though it is something that is all too frequently claimed.

 

[Wobblers]

[QUOTE 2001375, member: 45"]Read the rest of the thread. It's clearly explained.

If a group includes those carrying out a very low risk activity and those carrying out a significantly higher risk activity and an average risk rating is taken, this does not mean that the low risk activity now becomes more risky.

The stats are often wilfully misused to suggest that low-risk ped activity is higher risk than it is. That's where the common sense alert comes into play with the public and where they start to think we're nuts and stop listening.

See...[/quote]

Ah, you're talking about the pedestrian KSI figures. That's fair enough - it's often said that many pedestrian casualties are the result of drunkeness though I've never seen a figure for it. The raw figures have walking 10% more likely to end in death or serious injury in terms of distance travelled than cycling. That would certainly be lower, quite possibly substantially so, if the inebriated fraternity were removed.