Ben Goldacre - Helmet 'Bad Science'

[ufkacbln]

I think you'll find that bone and expanded polystyrene have rather different mechanical properties. It is not possible to infer levels of injury from damage to a helmet. Certainly you can't look at a cracked lid and infer that it prevented a cracked skull - not when one requries a full order of magnitude more energy to sustain damage than the other [1]. No meaningful comparison is possible. Unless we get the same, ahem, "dummy" to repeat the same carefully controlled experiment several hundred times both with and without helmet to get a reasonable statistical analysis.

Do we have any volunteers?

[1] For the benefit of the very-slow-on-the-uptake, I ought to say that skullls are stronger - that's the benefit of half a billion years of evolution for you

Can we also repeat wearing a Melon (or other fruit with a dual density and hard shell?

Can we also repeat wearing a Thudguard?

 

[srw]

Gone very quiet on this thread

Yup. Some numpty seems to have forgotten that this is a cyling forum not a motorcycling forum. And I can't remember if it's the same numpty or a different numpty who seems to have forgotten that he owes me an acknowledgement that he made a bit of a booboo upthread in describing a risk analysis.

@Adrian describes the situation perfectly. Inevitably there isn't data, so we wriggle off into anecdote and irrelevance. Just as Goldacre pointed out.

 

[Linford]

Yup. Some numpty seems to have forgotten that this is a cyling forum not a motorcycling forum. And I can't remember if it's the same numpty or a different numpty who seems to have forgotten that he owes me an acknowledgement that he made a bit of a booboo upthread in describing a risk analysis.

@Adrian describes the situation perfectly. Inevitably there isn't data, so we wriggle off into anecdote and irrelevance. Just as Goldacre pointed out.

What you are saying here is that any reference made to equipment which isn't marketed at cyclists is irrelevant ?

I am a cyclist

and a motorcyclist

It is very obvious that you can clearly only see only things from a cycling perspective. The protective (armoured) clothing in terms of cost which I am wearing in this pic is realistically valued at about £900....every bit is covered from the armoured boots, the certified armour in the suit to the carbon knuckle guards in the gloves ....I wear it not for the ride, but for the fall as I've had a few off over the years on both the track and road and they are incredibly painful (or else I would be wearing shorts, flip flops and maybe a stupid bandana as they do in some State in America)
The thing about an 'accident' (or incident for the pedantic) is that forces beyond your control are applied to you, and you are in the lap of the gods when you do fall....you become a spectator in the whole thing.

My motorcycle lid is too hot, too impractical and too heavy to be worn as a cycling helmet, but if someone did come up with a properly vented cycle lid which doesn't obstruct breathing, which had been made to motorcycle standards, I'd certainly be interested in looking at it (incidentally, all of the 'Sharp' testing and accrediting of lids where they have been seen to perform to the highest level is all with full face biker lids)

My weekly climb and descent on my cycle sees me knocking on the door of 50mph . Should I realistically be wearing biker gear for this bit...hell yea, the risk is more than substantial enough...the only mitigation is that the road has no turnings, fairly straight with vey good visibility, and is of a fairly high quality surface ...perhaps I ought to take a more gentle gradient or use the brakes more as I've dropped a motorbike at 50mph on the track and it hurt like hell even in full leathers and lid...and that was without hitting anything.
If you had experience of other modes you really wouldn't be so blinkered but your ego will continue to stop you from acknowledging anything anyone else has to say on this issue.

 

[srw]

What you are saying here is that any reference made to equipment which isn't marketed at cyclists is irrelevant ?

In discussions of BMJ editorial talking about cycling helmets, which is being undertaken between cyclists on a cycling forum? Hell, yes.

 

[Linford]

In discussions of BMJ editorial talking about cycling helmets, which is being undertaken between cyclists on a cycling forum? Hell, yes.

I'm not convinced by the argument of cycle at any cost (I read his article as saying that)...because statistically we are more likely to get fit than have a serious or fatal accident (durr...you don't say). this is still cold comfort for people who sustain a serious injury which could have been signfficantly reduced by the use of adequate head gear

 

[srw]

I'm not convinced by the argument of cycle at any cost (I read his article as saying that)...because statistically we are more likely to get fit than have a serious or fatal accident (durr...you don't say). this is still cold comfort for people who sustain a serious injury which could have been signfficantly reduced by the use of adequate head gear

You misread his article, then.

And those people for whom this is cold comfort - exactly how many of them would there be?

 

[Linford]

You misread his article, then.

And those people for whom this is cold comfort - exactly how many of them would there be?

Clearly not you as you have not and will never have a serious off...for all your talk about risk you don't appear to understand effect. ..

 

[Wobblers]

Here you are...a demonstration of your point and mine

I'd like to see your statistical analysis on that one (single anecdote, without any measurements).

Don't spare us the workings of your t-test, either, thanks!

 

[Wobblers]

I'm not convinced by the argument of cycle at any cost (I read his article as saying that)...because statistically we are more likely to get fit than have a serious or fatal accident (durr...you don't say). this is still cold comfort for people who sustain a serious injury which could have been signfficantly reduced by the use of adequate head gear

The assumption there that "adequate head gear" is

1. Available at reasonable cost
2. Is actually practical and fit for purpose for cycling
3. Does not increase the risk of incurring other serious injuries
4. Does not alter the cyclist's perception of risk in such a way that they engage in more risk taking [1]

I suspect that may be cold comfort to those in cardiac wards, unable to get out of bed thanks to a permanently damaged heart (well, if you can drag in all sorts of silly emotional stuff, why not me?).


[1] Risk compensation is a very well observed and documented phenomenon. To anyone who claims it has no effect here, they're going to have to back up that rather extraordionary claim with supporting evidence to explain why, as it occurs in every other activity where there is risk, it is not apparent in cycling.

 

[Fab Foodie]

To cut a very long story short cycle helmets are designed and tested to provide adequate energy absorbtion in low speed impacts.....

And this Ladies and Gentlemen is pretty much all you need to know.

 

[ufkacbln]

And this Ladies and Gentlemen is pretty much all you need to know.

... apart from the fact that EN1078 is considered to be so laughably weak and offer so little protection that they are banned from use in the US for competition!
Never buy a halmet that does not also pass one of the higher standards such as Snell, CSPC etc

 

[PpPete]

... apart from the fact that EN1078 is considered to be so laughably weak and offer so little protection that they are banned from use in the US for competition!
Never buy a halmet that does not also pass one of the higher standards such as Snell, CSPC etc

Another frequently trotted out fallacy.
Have you actually read and compared the testing that goes into approval for these standards?
The tests are all very similar, slightly different shaped impactors, slight differences in drop heights - but broadly similar energy levels.**

The fact that EN1078 certified helmets are (apparently) not permitted in US competions is not evidence. There are a great number of helmets that are sold as CSPC certified in the US and as EN1078 in the UK. Why? Because that's the law of the land.

** last time I looked the only standard which was tested with significantly higher energy levels was the Snell B95 standard. Good luck finding a helmet that is certified to that - even in the USA.

 

[ufkacbln]

Another frequently trotted out fallacy.
Have you actually read and compared the testing that goes into approval for these standards?

Yes I am, fully aware of the testing and the arguments about anvil size, shape, impact energy, retention, cleaning, coverage of common impact areas, sliding resistance etc.

I am also aware of the discussions as to why we need better standards for helmets that include an international standard that includes common ground on snag points and crash retention.

The tests are all very similar, slightly different shaped impactors, slight differences in drop heights - but broadly similar energy levels.**

Which is exactly the point they are tested further than EN1078, helmets passing only the EN1078 can and do fail the other tests. EN1078 on its own is not a strong test.

Even down to the simple fact that some allow manufacturers to present a test batch or prototype whereas others test the "off the shelf" helmet.

This is important.... take the example of the Trek Anthem which passed CPSC, yet when independent tests were carried out the actual model in the shops failed to meet the most basic standards and was recalled.

EN1078 test a helmet has a drop test onto a hard surface from 1.5 metres with a maximum peak translational acceleration to the head of 250g.

The CPSC has a drop height of 2.0m, with a maximum translational peak acceleration to the head of 300g.

The Snell B-95 has a drop height to 2.2 metres and 300g

Are you really saying that a helmet tested and proven to resist higher drop distances and a greater force is not going to offer more protection in real life?

Is it really unwise to look for a helmet that passes the higher standards!

The fact that EN1078 certified helmets are (apparently) not permitted in US competitions is not evidence. There are a great number of helmets that are sold as CSPC certified in the US and as EN1078 in the UK. Why? Because that's the law of the land.

The fact that a helmet can pass EN1078 and offer insufficient protection to be endorsed is not evidence that the test is weak?

... and does the legal status make them safer and more efficient - I suspect not.

Surely you aren't arguing that because a helmet can pass the limp EN1078 and be sold in the UK does not mean that you cannot seek out better tested helmets

Catlike for instance have chosen not to test beyond EN1078 and hence ignore the US market:

All Catlike Helmets conform to the European standard CE EN1078. If you intend to use the helmet outside of the EU, Catlike, Nemesis GB and Prendas Ciclismo will not be held responsible for any legal actions or any other forms of actions that may occur.

If you do intend on riding in events in the USA, it is interesting to note that Cycling USA does allow the of CE EN1078 helmets.

Look at the packaging and see what other tests have been performed and choose a helmet that passes these- it is really that simple

** last time I looked the only standard which was tested with significantly higher energy levels was the Snell B95 standard.

That is ironic when you ask about knowledge of the testing procedures, yet seem to be illustrating a certain ignorance of the facts... Snell B95 uses 300g, as does CPSC

When comparing the other tests like CPSC and EN1078 the difference between 250g and 300g is "broadly similar" yet when comparing with Snell B95 with EN1078, the 300g is "significantly higher"

Which one is it?


Actually a demonstration of how we have allowed the protection offered by helmets to be eroded to the weak tests like EN1078

Most helmets these days are unable to pass the same tests that almost all helmets did pass 15 years ago

Good luck finding a helmet that is certified to that - even in the USA

Do you really think it is that difficult?

Two of my three local bike shops can sell me helmets that pass Snell B95 and a whole range that pass Snell B90, one shop even has a choice of Snell B95 helmets!

In fact virtually every on line shop from Hargroves, Evans, Cycle Surgery, Harry Hall, LEisure Lakes and most others can offer B95 certified helmets from stock!

I think that a knowledge of cycle helmets is standing me in better stead than luck!

 

[PpPete]

You seem to be implying that there is just one test that makes up these standards.

You can argue almost anything you want if you pull a single test out and compare that across a range of standards - especially if you pull out peak acceleration figures instead of thinking about energy absorbtion (which I was very careful to use)

You also seek to infer that I'm saying we shouldn't be looking for better helmets - which is very far from the truth.

 

[ufkacbln]

You seem to be implying that there is just one test that makes up these standards.

Just one test?

How did you get that from the list I gave?

.........anvil size, shape, impact energy, retention, cleaning, coverage of common impact areas, sliding resistance etc.

I also quoted three different standards!

You can argue almost anything you want if you pull a single test out and compare that across a range of standards - especially if you pull out peak acceleration figures instead of thinking about energy absorbtion (which I was very careful to use)

Nope - I raised a number of points such as whether the test is carried out on "off the shelf" products or not, the others re just part of a simple summary

You also seek to infer that I'm saying we shouldn't be looking for better helmets - which is very far from the truth.

How on earth did you get that from :

Look at the packaging and see what other tests have been performed and choose a helmet that passes these- it is really that simple

Are you really saying that a helmet tested and proven to resist higher drop distances and a greater force is not going to offer more protection in real life?

Is it really unwise to look for a helmet that passes the higher standards!

I am also aware of the discussions as to why we need better standards for helmets that include an international standard that includes common ground on snag points and crash retention.

This clearly advocates looking for a helmet that passes a higher standard, and that any helmet passing En1078 alone should be passed over in favour of one passing the tougher tests.