tag:blogger.com,1999:blog-2878024090187291563.post3031047753997092354..comments2022-03-30T11:56:53.119-07:00Comments on The Bike Helmet Blog: My Bike Helmet Saved My Life!Sue Knauphttp://www.blogger.com/profile/14149859995220789372noreply@blogger.comBlogger56125tag:blogger.com,1999:blog-2878024090187291563.post-74857558550510958252016-03-06T10:28:27.984-07:002016-03-06T10:28:27.984-07:00Hi Ron,
Glad you like this one.
Your use of the...Hi Ron,<br /><br />Glad you like this one. <br /><br />Your use of the image is a different topic, though and may detract from this one. I wonder if viewers will flip it and imagine that bicycling is horribly dangerous because drivers are indeed talking on their phone and therefore run over ever cyclist on the road. Just my thought.<br /><br />SueSue Knauphttps://www.blogger.com/profile/14149859995220789372noreply@blogger.comtag:blogger.com,1999:blog-2878024090187291563.post-36511796272612586232016-03-06T02:33:18.069-07:002016-03-06T02:33:18.069-07:00Dear Sue,
Great message, thanks.
I nicked your bro...Dear Sue,<br />Great message, thanks.<br />I nicked your broken helmet image, I hope you don't mind.<br />https://twitter.com/ron611087/status/706411653722738688Ronhttps://www.blogger.com/profile/08124063684978419009noreply@blogger.comtag:blogger.com,1999:blog-2878024090187291563.post-15410870462657242282016-02-18T09:16:39.799-07:002016-02-18T09:16:39.799-07:00That sounds interesting. Have you tried this in Ca...That sounds interesting. Have you tried this in Canada? <br /><br />For Australia, the best organization to start with would be Freestyle Cyclists: http://www.freestylecyclists.org/. While lots of smaller groups around the country are also fighting their helmet law, Freestyle is entirely focused on this issue and shifting views of cycling back to a normal activity. <br /><br />Let me know if you or they give this interesting angle a try.Sue Knauphttps://www.blogger.com/profile/14149859995220789372noreply@blogger.comtag:blogger.com,1999:blog-2878024090187291563.post-68166403539322344492016-02-18T08:21:08.901-07:002016-02-18T08:21:08.901-07:00Sue>> It was in fact a reply to Andrew Redma...Sue>> It was in fact a reply to Andrew Redman's comment above, and I'll try to remember to specify my responses going forward. Thanks as well for the onestreet.org link, it's another excellent resource for factual information re bicycle helmets and I've bookmarked it for future debates. <br /><br />I have one other question for you, I'm assuming that Australia like here in Canada has a charter of Rights and Freedoms. Has anyone challenged the bicycle helmet law, (or in my case here bike club policy)as being discriminatory exclusion based on the "arbitrary and capricious" argument? In US law arbitrary and capricious means that there is "an absence of a rational connection between the facts found and the choice made" http://definitions.uslegal.com/a/arbitrary-and-capricious/. If a case based on that argument made it to a higher court a full accounting of the research for and against helmet efficacy would be made part of the public record and hopefully a sound judgement would prevail.<br />Anonymoushttps://www.blogger.com/profile/04361805694891343024noreply@blogger.comtag:blogger.com,1999:blog-2878024090187291563.post-24386617251158191282016-02-14T12:32:09.338-07:002016-02-14T12:32:09.338-07:00Thanks Alex. I assume from your earlier comments t...Thanks Alex. I assume from your earlier comments that this latest one is not directed at me. If you would like your question answered by a particular commenter, maybe include their name or repost this as a reply to their comment. <br /><br />Nice additions by the way. There are a few graphs showing why helmets for car drivers and pedestrians make more sense, posted here: http://www.onestreet.org/resources-for-increasing-bicycling/136-bicycle-helmets Sue Knauphttps://www.blogger.com/profile/14149859995220789372noreply@blogger.comtag:blogger.com,1999:blog-2878024090187291563.post-9843608729679918862016-02-14T12:12:31.953-07:002016-02-14T12:12:31.953-07:00This is what neuroscience has to say about the eff...This is what neuroscience has to say about the efficacy of bike helmets;<br />http://www.cbc.ca/news/health/bike-helmets-should-address-concussion-risk-scientists-say-1.1367454 . Further you have not in any way addressed the need for bicycle helmets as opposed to walking or car helmets when the rate of head injuries per unit of time for both of those activities is pretty much equal to that of bicycling. <br />One question I do have ask you is whether you work for a bicycle helmet manufacturer or in any other way are financially compensated directly or indirectly from the sale of bicycle helmets?Anonymoushttps://www.blogger.com/profile/04361805694891343024noreply@blogger.comtag:blogger.com,1999:blog-2878024090187291563.post-55771955450121353072015-10-09T11:11:39.128-07:002015-10-09T11:11:39.128-07:00Hi Andrew,
I very much appreciate how you have pl...Hi Andrew,<br /><br />I very much appreciate how you have placed your viewpoint in context here. Even as a bike helmet tester you caution against relying on helmets for safety. That's a refreshing change from most helmet manufacturers who stay interestingly quiet as people project fictional expectations onto their product.<br /><br />I still have to defend my claims, though. Your analogy of the jelly doesn't coincide with a brain. There is actually a space between the brain and the skull so there can be damage at both ends. <br /><br />More importantly, most bicycle helmets are manufactured to the minimum requirements and that is why they break at about 13mph impact, at which point they offer zero protection. The question to ask is whether an unhelmeted head would experience brain damage below that speed of impact, including whether the head would have hit at all without the helmet’s added weight and diameter. A laboratory test would not include human instinct. The smallest babies learn how to fall without hitting their head. If we fall from a standstill so that our head would impact the ground at the approximate maximum impact speed that most bicycle helmets are designed for, we will bend our neck to avoid our head hitting. We do this in any crash. But the added weight and diameter of the helmet throws off this natural protection. Have your studies included these factors?<br /><br />Perhaps the most important point is the vast gap between what people expect from their bicycle helmet and the protection that helmet actually offers. You note that some manufacturers go beyond the CPSC requirements of testing the top only. Such exceptions are not what I'm talking about. Most bicycle helmet manufacturers simply test to the minimum and design to that minimum. And even if they were to test further, in order to create a helmet that protects the entire head and does not break at 13mph or even your personal line of 20mph, the cost of such a helmet would far exceed the amount most people would pay for one. And that helmet would still not PREVENT brain damage. It would also look rather like a motorcycle helmet. <br /><br />We cannot expect to encourage most people to ride a bike if we say they must wear a helmet in order to do so. To tell people to wear a bicycle helmet, any bicycle helmet, in order to "be safe" or to "protect their brain" gives the false impression that any bicycle helmet will prevent brain damage in any crash no matter the speed of impact. <br /><br />If we were to change that message to be closer to the truth and say that they should only ride a bike if they wear this specific helmet that looks like a motorcycle helmet that will protect their skull and perhaps prevent some brain damage up to a total impact speed of say 15mph, does such a message solve the problem with bicycle helmets?<br /><br />Then consider that bicycling is one of the least likely ways a person can sustain a head injury. Car occupants are far more likely to sustain a head injury - see the graph posted on this page: http://www.onestreet.org/resources-for-increasing-bicycling/136-bicycle-helmets . Let's start asking why bicycling has been singled out for fanciful stories of heads splitting open that can only be done with a bit of foam stuck to the head, when riding in a car is far more dangerous and walking is equally as dangerous. No one yells at car occupants or pedestrians demanding to know where their helmet is. But helmetless cyclists are frequently harassed in this way.<br /><br />I applaud your ability to put your work in context. I hope you can also help your colleagues to start speaking up when their products are placed on false pedestals of magical protection. This will contribute to bicycle helmets finally being seen by most people as providing the very limited protection they do. From there we can shift our messaging about riding bikes so that bicycling will finally be presented as a means of moving about as natural and safe as walking.Sue Knauphttps://www.blogger.com/profile/14149859995220789372noreply@blogger.comtag:blogger.com,1999:blog-2878024090187291563.post-35779505179882590472015-10-09T07:34:27.996-07:002015-10-09T07:34:27.996-07:00Sue I absolutely support your honourable aims here...Sue I absolutely support your honourable aims here. I totally agree that helmets breaking up on impact is not a good thing. And nor is a helmet law the solution. <br /><br />Helmets are just one form of protection, that will only help in very specific circumstances. <br /><br />However where I do have a problem with what you are saying is that you are completely wrong where you say that helmets don't reduce the acceleration of your brain, or that they are only tested on the top.<br /><br />To describe the mechanics of impact induced brain injury, I use the analogy of a jelly within a glass bowl. If you slam that bowl sideways into something, the jelly does slump towards the impact, and if the impact is hard enough, you'll find the worst damage to the jelly is at the back, where it tears away from the bowl. <br /><br />Imagine then that you have two bowls travelling at the same speed. One slams into a brick wall stopping dead and the other lands in a nice soft cushiony pillow. Which jelly will be more badly damaged?<br /><br />I have been involved in a lot of cycle helmet testing as we have been designing a helmet to try and overcome some of these issues such as breaking apart on one hit, poor fit etc. We have carried out nearly 2000 tests on various Prototype and material samples including EPS. I have seen an awful lot of data - and it clearly shows that, at the speeds specified in the tests, a head with no impact absorbing material will experience up to around 2000g deceleration. Just 25mm of EPS reduces the head deceleration to around 180g - 200g.<br /><br />Can your brain survive 200g? Yes if you're lucky. It will probably be damaged, but can survive. Can it survive 2000g? No.<br /><br />Secondly in fact if you talk to the professionals about this, you'll find out that they do in fact test helmets all over, on the sides, back etc (within the areas above the lines specified in the standard). Certainly EN1078 states that the tester should select any area that looks weak. So again, I am afraid you're wrong saying that they only test the top.<br /><br />So whilst I agree that current helmets and the safety standards have their shortcomings (we're working to try and solve that), spreading confusion about the physics and testing methods is not going to help people either. <br /><br />And for the record I commute by bike to work every day. Having seen what a head slamming into something at 20mph looks and sounds like, I now always wear a helmet if I can. BUT I will also try and cycle as safely as I can, because the helmet will only help my head out a bit and it won't protect my internal organs, limbs etc. Whilst we're working to improve the safety of helmets, I know that's a stop gap. What I'd really like is for the roads to be safer... something I think we all agree on.Anonymoushttps://www.blogger.com/profile/06251754056029471081noreply@blogger.comtag:blogger.com,1999:blog-2878024090187291563.post-36019008959784710462015-10-09T07:07:51.891-07:002015-10-09T07:07:51.891-07:00This comment has been removed by the author.Anonymoushttps://www.blogger.com/profile/06251754056029471081noreply@blogger.comtag:blogger.com,1999:blog-2878024090187291563.post-4607318378907820102015-09-22T17:53:45.306-07:002015-09-22T17:53:45.306-07:00Well put. Thank you. And good luck with your recov...Well put. Thank you. And good luck with your recovery. Once you're back on your bike, keep in mind the limited protection a bike helmet will offer. I hope someday soon Australia will shift their bike policy efforts away from helmets and into improving roadways so you won't have to ride in potentially dangerous situations.Sue Knauphttps://www.blogger.com/profile/14149859995220789372noreply@blogger.comtag:blogger.com,1999:blog-2878024090187291563.post-81193456194633549642015-09-22T17:46:32.504-07:002015-09-22T17:46:32.504-07:00I am still in hospital after being hit by a truck....I am still in hospital after being hit by a truck. I had blood on the brain, concussion, major fractures etc. I have come to the conclusion that I probably do need to wear a helmet in Australia for the type of journey I was on - urban, potentially dangerous. Does this require a compulsory HL though ? No. Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-2878024090187291563.post-45704233253416284302015-09-05T13:03:21.500-07:002015-09-05T13:03:21.500-07:00Either you fundamentally don't understand phys...Either you fundamentally don't understand physics, or you're simply not interested at all in whether what you say is true or false.RWhttps://www.blogger.com/profile/07858934058244484435noreply@blogger.comtag:blogger.com,1999:blog-2878024090187291563.post-90306560424527975462015-09-05T10:13:09.596-07:002015-09-05T10:13:09.596-07:00Crumple zone comparison only works with bike helme...Crumple zone comparison only works with bike helmets up to 13mph. When they break they are not absorbing anything. Even up to 13mph, cannot prevent brain damage.<br /><br />Studies to find - Proves that bike helmet slows acceleration of brain.<br />Bike helmet tests to find - directly to side and back.Sue Knauphttps://www.blogger.com/profile/14149859995220789372noreply@blogger.comtag:blogger.com,1999:blog-2878024090187291563.post-45423172212211305892015-09-05T09:56:47.289-07:002015-09-05T09:56:47.289-07:00I didn't say I found your post scandalous exce...I didn't say I found your post scandalous except for one point where you were clearly dishonest. I said that you misrepresented and misunderstood various facts. But you've misrepresented and misunderstood my points. I should have expected that I suppose.<br /><br />You missed the point about crumple zones. The fact that they crumple is what makes them a safety feature. They absorb energy. But you were arguing that anything that breaks or deforms on impact is a failure. You are wrong.<br /><br />"There is no way to seat belt our brains" - how very sad that would be, if true. But if you want to reduce the acceleration of your brain inside your skull after an impact, wear a helmet or otherwise pad your head. Skateboarders know this. Skiers know it. Motorcyclists know it. Many cyclists know it too. Apparently, you don't.<br /><br />You said "if you drop your bike helmet, the warranty is void and you must replace it". You falsely put that forward as generally true, when it isn't. If you find that you don't like the terms of the guarantee offered by Nutcase Helmets, buy your helmet from, say, Giro, whose guarantee says nothing about being voided if the helmet is dropped: http://www.giro.com/eu_en/cycling-faqs/<br /><br />"different part" is not vague language. You falsely claimed that only the top part of the helmet is tested. That is not true.<br /><br />"We actually agree on the result of the lawsuit - the victim could not prove that he'd adjusted his helmet correctly. That was my point."<br /><br />No, we don't, and your misrepresentation of what I said and what the lawsuit found is immature. The victim would never have to prove that he'd adjusted his helmet correctly, because that would be impossible. The helmet manufacturer in fact proved that he was wearing his helmet incorrectly. That is a very different thing. Do you understand the difference?<br /><br />Seems like you really don't understand cycling, or else you're trying to fool gullible readers again. Downhill helmets are for downhill biking, in which the risk of crashing is high and facial protection is highly desirable. No-one uses or advocates using downhill helmets for road cycling.<br /><br />I suspect that you would consider any study that proves you wrong to be biased. So, before I point out some relevant literature, define clearly what criteria you use to decide whether a study is biased or not.RWhttps://www.blogger.com/profile/07858934058244484435noreply@blogger.comtag:blogger.com,1999:blog-2878024090187291563.post-15371606687123004352015-09-04T22:31:19.399-07:002015-09-04T22:31:19.399-07:00Thanks Kathy. Great news about the extension and t...Thanks Kathy. Great news about the extension and that submissions are rolling in. Would you mind posting that link to the comments section of the article about that effort on this blog? It's still attracting more readers and I'm sure they'll like to know they still have a chance to submit their thoughts.Sue Knauphttps://www.blogger.com/profile/14149859995220789372noreply@blogger.comtag:blogger.com,1999:blog-2878024090187291563.post-43752745312424615262015-09-04T22:26:31.156-07:002015-09-04T22:26:31.156-07:00Thanks for venting Alex. Good stuff. I'm sorry...Thanks for venting Alex. Good stuff. I'm sorry you are having such a hard time as a helmet-free rider. But keep at it. This information must become as pervasive as the misinformation has become.Sue Knauphttps://www.blogger.com/profile/14149859995220789372noreply@blogger.comtag:blogger.com,1999:blog-2878024090187291563.post-41632065732384660092015-09-04T15:44:15.233-07:002015-09-04T15:44:15.233-07:00Hi this topic is close to my heart. Having lived i...Hi this topic is close to my heart. Having lived in BC and mostly loved it I can say that the ridiculous nanny-ing not so much from the state cause the cops never bothered me but from individuals for not wearing a bike helmet was one of the few things I don't miss about Vancouver. That said Toronto doesn't have helmet laws but we have at least as many anti-science do gooders as on the west coast. For all the helmet evangelists I suggest you do some research on the efficacy of bike helmets. Here's a pretty decent CBC article that flat out states, in a quote from Toronto neurosurgeon Charles Tator. that bike helmets have not protective benefit against concussions. <br /><br />http://www.cbc.ca/news/health/bike-helmets-should-address-concussion-risk-scientists-say-1.1367454<br /><br />Further some of these links are no longer valid but here is a list of research pro and mostly con re the efficacy of helmets and the legitimacy of helmet laws/shaming.<br /><br />http://www.cyclehelmets.org/1160.html<br /><br />Thanks, I needed to vent on this, I was denied membership in a social, read casual, bike club because I don't wear a helmet. I'm thinking about a Charter of Rights violation case but need to read up a little more on that law.Anonymoushttps://www.blogger.com/profile/04361805694891343024noreply@blogger.comtag:blogger.com,1999:blog-2878024090187291563.post-40456557101799727492015-09-04T14:13:54.929-07:002015-09-04T14:13:54.929-07:00Hi Sue,
I just found your blog - great initiative....Hi Sue,<br />I just found your blog - great initiative. As you mentioned in an earlier post, Australia is currently holding a Senate Inquiry into personal choice, including bicycle helmets. The deadline for submissions on helmets has been extended to 5th October, and to date a number of submissions have been received from non Australian residents, so it is not limited that way. The perspective from elsewhere, especially people who have experienced cycling both in Australia and elsewhere, is valuable. The link for submissions is http://www.aph.gov.au/Parliamentary_Business/Committees/Senate/Economics/Personal_choice/Submissions<br />Your own initial blog post would make a good submission in itself.<br />BTW, I found posting on your comments a bit difficult. I'm used to being able to use facebook or an email to enter comments on online forums.<br />Anonymoushttps://www.blogger.com/profile/15499936839118094208noreply@blogger.comtag:blogger.com,1999:blog-2878024090187291563.post-67697994053218439482015-09-04T10:50:14.656-07:002015-09-04T10:50:14.656-07:00And since the maximum force a helmet can provide p...And since the maximum force a helmet can provide protection from is one equivalent to a simple fall from a standing height before it breaks apart, the suggestion that a broken helmet has saved a life suggests that that type of fall most often results in death. This we know is not true otherwise people who have simple falls without helmets on (almost everyone in life) would be dying. bradhttps://www.blogger.com/profile/11403942485155177704noreply@blogger.comtag:blogger.com,1999:blog-2878024090187291563.post-57766388489478301962015-09-03T15:09:18.487-07:002015-09-03T15:09:18.487-07:00This comment has been removed by the author.Anonymoushttps://www.blogger.com/profile/15499936839118094208noreply@blogger.comtag:blogger.com,1999:blog-2878024090187291563.post-55497393007844101932015-09-03T11:17:13.148-07:002015-09-03T11:17:13.148-07:00RW, I'm a bit at a loss as to why you find my ...RW, I'm a bit at a loss as to why you find my post so scandalous. In fact, with just a few additional details, you and I seem to agree on most points.<br /><br />Crumple zones - please consider that people inside cars are still expected to wear seat belts. There is no way to seat belt our brains.<br /><br />Here is one helmet warranty that is void from dropping: http://au.nutcasehelmets.com/warranty/ . Others simply specify any damage. Many will replace them for free if you can prove you crashed, but most will not simply for dropping it.<br /><br />Regarding the test, I specified "top part" of the helmet. You'll note in this and other tests done around the world that bike helmets are never tested for direct blows to the side or back. If you find one that tests directly to the side or back (not vague language like "different part"), please post it here.<br /><br />We actually agree on the result of the lawsuit - the victim could not prove that he'd adjusted his helmet correctly. That was my point.<br /><br />This article shows some images of bike helmets that look much like motorcycle helmets: http://www.outdoorgearlab.com/Downhill-Helmet-Reviews<br /><br />And finally, if you know of an unbiased study that proves that bicycle helmets reduce the acceleration of the brain, please post it here. Sue Knauphttps://www.blogger.com/profile/14149859995220789372noreply@blogger.comtag:blogger.com,1999:blog-2878024090187291563.post-70101374975598658142015-09-03T06:27:16.107-07:002015-09-03T06:27:16.107-07:00It seems Bob feels head injuries happen to people ...It seems Bob feels head injuries happen to people on bicycles more often than they happen to people who are not on bicycles and that's just not true. His argument that someone without a helmet obviously doesn't have a brain to worry about is applicable to everyone. Head injuries are a fact of life but reality has shown us that 1) the chance of receiving a serious head injury is relatively low, and 2) there is no clear evidence that bicycle helmet use has done anything to reduce serious head injury bradhttps://www.blogger.com/profile/11403942485155177704noreply@blogger.comtag:blogger.com,1999:blog-2878024090187291563.post-40839076814824418592015-09-02T15:58:18.419-07:002015-09-02T15:58:18.419-07:00"They come in at least eight sizes, depending..."They come in at least eight sizes, depending on the manufacturer. Then, assuming you choose the correct size, you must spend time micro-adjusting the strap so the helmet sits just so on your head, otherwise there is no expectation for it to protect you at all. Here’s the result of a lawsuit won by a bike helmet manufacturer because the victim, an experienced cyclist, could not prove that he had adjusted the helmet straps correctly."<br /><br />That's just scandalously dishonest of you. The cyclist specifically claimed that the helmet rotated to expose his head to injury. The judgement said nothing about whether or not his straps were adjusted correctly. It was found that he was wearing the helmet incorrectly, and suffered an impact to part of his head not covered by the helmet as a result. Here is a summary of the case:<br /><br />http://verdictsearch.com/verdict/cyclist-wore-helmet-too-high-resulting-in-brain-injuries-defense/<br /><br />"Some bike helmet manufacturers are trying to do the right thing by developing helmets that can withstand greater impact. The results are extremely expensive helmets that usually look a lot like motorcycle helmets. Are we really going to encourage more people to ride bikes if they have to wear a motorcycle helmet?"<br /><br />I never saw a bike helmet that looked remotely like a motorbike helmet. Got any examples?<br /><br />"All of this still doesn’t get at the larger issue – that no helmet, not even a motorcycle helmet, can prevent brain injury."<br /><br />Anything which reduces the acceleration of the brain inside the skull can prevent brain injury. People wear helmets in all sorts of situations for this reason. To deny the basic concept is pretty bizarre.<br /><br />"Nothing can prevent a brain from slamming into the inside of its skull."<br /><br />Replace "nothing" with "Any kind of padding" and you're basically correct.<br /><br />"After more than a decade of researching and discussing the bicycle helmet problem I’m more than frustrated with its significant harm to bicycle advocacy efforts. I tend to get a twitchy when I’m forced to listen to an impassioned proclamation that a bit of Styrofoam saved someone’s life. I’m ready for bike helmets to be seen as what they actually are – just a bit of Styrofoam, nothing more, nothing less. If someone feels better riding their bike with a bit of Styrofoam on their head, cool, go for it. But please, let’s stop the irrational claims that these things save lives because they break apart at impact."<br /><br />Again you seem to think that the material it's made of is your killer point. Bicycle helmets save lives because they reduce the acceleration of the head in impacts. That's not irrational. In fact, it's common sense. In particularly bad impacts, they might break. It's not the breakage but the reduction of acceleration that has the beneficial effect.<br /><br />If you don't want to wear something that will soften the blow in case of an impact while cycling, then cool, don't. But don't lie about, misrepresent and misinterpret the data to try to persuade others not to do so. That's what is truly irrational here.RWhttps://www.blogger.com/profile/07858934058244484435noreply@blogger.comtag:blogger.com,1999:blog-2878024090187291563.post-58834155585978163562015-09-02T15:57:05.796-07:002015-09-02T15:57:05.796-07:00Your post is full of misunderstandings and misrepr...Your post is full of misunderstandings and misrepresentations.<br /><br />"What other safety devices do people hold to such a low standard? If I life jacket tore apart and floated away as soon as you hit the water, would you claim that it saved your life? If a seat belt released upon impact, would this bring it accolades?"<br /><br />Your examples are nonsense. A life jacket is supposed to make you float. A seat belt is supposed to prevent you from being thrown forward. Do you know what a bike helmet is actually supposed to do? It's supposed to absorb energy from an impact and prevent it from being transferred directly to the head. Crumple zones in cars perform a similar function. If you have a major impact, and your car doesn't crumple, you'll probably be dead. If it does crumple you might get away with a less serious injury. You could point to your thoroughly crushed car and legitimately say that it saved your life. A helmet which didn't break or distort in a severe impact would instead transfer energy directly to the head. Is that what you think it should do?<br /><br />"In fact, bike helmet manufacturers brazenly admit how fragile their helmets are – if you drop your bike helmet, the warranty is void and you must replace it."<br /><br />I checked as many bike helmet guarantees as I could find online, and I found none which said anything like this.<br /><br />"They are, after all, just a bit of Styrofoam."<br /><br />True, and banal. A book is just a lot of sheets of paper. The air is just a gas made mostly of nitrogen. I don't think you're letting anyone in on some big secret here. Expanded polystyrene foam has properties which make it a desirable material from which to make helmets.<br /><br />"They only need to test their helmets to a total impact velocity of 20 feet per second, which translates to 13.64 miles per hour (21.95 kilometers per hour). That’s about the same speed a head reaches when a person of average height falls over from a standstill."<br /><br />From the link you posted, this speed "typically means that the helmet must drop at least 6½ feet". A person of average height is not 6½ feet tall. You seek to imply that the test is passed if the helmet does not break on the impact. The test described is an impact attenuation test, and a helmet fails the test if any of the samples tested under any of the conditions described above shows a peak acceleration of more than 300g. Also, the test is a US test, not a global one. Cycle helmet standards that are not ideal in one part of the world do not imply that all cycle helmets everywhere are deficient.<br /><br />"Think about this. If you are in a crash of any speed whatsoever and your helmet breaks apart at the initial impact, your head is not only unprotected at impact, it remains so through the rest of the crash."<br /><br />In fact, by absorbing energy that would otherwise have been transferred directly to your head, the helmet was protecting your head at impact. This is quite obvious. Indeed, it can't protect your head after it's been broken. Not really a way around that, but it hardly argues against wearing a helmet in the first place.<br /><br />"The low impact speed for which bike helmets are designed is troubling enough. Then consider that the tests are also limited to the top parts of the helmets, never blows to the side or back. Take a close look at the diagrams in that CPSC link to see this. I suppose if crash victims could reorient themselves during a crash to ensure they only hit the top of their head, this could be useful, at very low speeds anyway."<br /><br />From the document you linked to: "Drop helmets 1 through 4 on the schedule above each a total of 4 times, twice on the flat anvil and twice on the hemispherical anvil.... Make sure that a different part of the helmet hits the anvil each time. This means that you must adjust the headform after each drop."<br /><br />"But then consider that bike helmets must be fitted perfectly to each wearer in order to be useful at all."<br /><br />Not true.RWhttps://www.blogger.com/profile/07858934058244484435noreply@blogger.comtag:blogger.com,1999:blog-2878024090187291563.post-1821171743922459802015-09-01T21:34:17.889-07:002015-09-01T21:34:17.889-07:00Unfortunately, many, many people are suggesting th...Unfortunately, many, many people are suggesting that broken bike helmets offer protection. That is the point of this blog post.Sue Knauphttps://www.blogger.com/profile/14149859995220789372noreply@blogger.com