Which is the Safest Helmet?
06-05-15 | 10:10 AM
#51
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Helmet manufacturers recommend replacement after a time period due to material aging, UV, and experience with their products from field evaluations. Every time your helmet takes a hit - thing like dropping it on a hard surface - you cause compressive damage to the material of the helmet that can cumulatively lessen it's ability to provide protection.
Qualitatively, as a ski patroller, when I look at my helmet after three or so years of use, it's got dings all over it from my handling of it and from getting normal bumps in the head in the course of it's skiing usage. Same goes for my bike helmets. We use them a lot and they are not babied but used in real life. The material in them is designed to crush on impact and it does not spring back, hence the damage is cumulative...[SKIP]
...and because we're seeking the maximum effective protection (why wear one otherwise?). Materials age and we don't necessarily take care of things in an ideal manner. Our helmets are heavily used.
Qualitatively, as a ski patroller, when I look at my helmet after three or so years of use, it's got dings all over it from my handling of it and from getting normal bumps in the head in the course of it's skiing usage. Same goes for my bike helmets. We use them a lot and they are not babied but used in real life. The material in them is designed to crush on impact and it does not spring back, hence the damage is cumulative...[SKIP]
...and because we're seeking the maximum effective protection (why wear one otherwise?). Materials age and we don't necessarily take care of things in an ideal manner. Our helmets are heavily used.
Perhaps you might consider taking better care of your safety equipment, it might help you in your goal of maximum effective protection.
06-05-15 | 10:17 AM
#52
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I agree with everything you wrote except the first sentence. Based on the study, it would seem that material aging and UV probably are not a factor They didn't control for UV exposure, but the large data set would suggest that they would have captured at least some "UV damaged" helmets. Is there any data from manufacturers to support the recommended replacement interval?
I think that helmet manufacturers recommend replacement to sell more helmets, using safety as an issue.
All of this points out that time is not a factor. So why replace a helmet after a certain time period at all?
I think that helmet manufacturers recommend replacement to sell more helmets, using safety as an issue.
All of this points out that time is not a factor. So why replace a helmet after a certain time period at all?
06-05-15 | 10:18 AM
#53
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Last edited by JohnJ80; 06-05-15 at 10:34 AM.
06-05-15 | 10:28 AM
#55
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I agree with everything you wrote except the first sentence. Based on the study, it would seem that material aging and UV probably are not a factor They didn't control for UV exposure, but the large data set would suggest that they would have captured at least some "UV damaged" helmets. Is there any data from manufacturers to support the recommended replacement interval?
I think that helmet manufacturers recommend replacement to sell more helmets, using safety as an issue.
All of this points out that time is not a factor. So why replace a helmet after a certain time period at all?
I think this points out that a good "pre-flight check" should include a helmet inspection, along with air pressure in your tires, brakes working, quick releases secured, etc. I've banged a helmet twice in 40 years of riding. Each time I replaced it.
One thing that isn't mentioned is that the fitting systems seem to degrade over time. I replace my helmets when the nylon webbing starts to get gunky and start to slip, making it more and more difficult to put it on and adjusted correctly. Most thelmets nowadays have a plastic thing in the back of your head. I had one on an older helmet snag and break awhile back. I have two helmets, I rotate them so they dry out. I find that the pads last longer when given a chance to dry, which is part of the fitting system.
Let's say you take a helmet into a shop, like I did a few years ago just to see what they would say. They didn't really inspect it, but they did ask how old it was. They recommended I replace it becuase it was over 5 years old. Why? Manufacturer's recommendation-the same guys that want to sell you a new helmet. And it was the right thing to do at the shop. To say otherwise might lead to a future lawsuit. I wonder if they would have inspected it if I said it was 2 years old. I'll try that experiment some other time.
I think that helmet manufacturers recommend replacement to sell more helmets, using safety as an issue.
All of this points out that time is not a factor. So why replace a helmet after a certain time period at all?
I think this points out that a good "pre-flight check" should include a helmet inspection, along with air pressure in your tires, brakes working, quick releases secured, etc. I've banged a helmet twice in 40 years of riding. Each time I replaced it.
One thing that isn't mentioned is that the fitting systems seem to degrade over time. I replace my helmets when the nylon webbing starts to get gunky and start to slip, making it more and more difficult to put it on and adjusted correctly. Most thelmets nowadays have a plastic thing in the back of your head. I had one on an older helmet snag and break awhile back. I have two helmets, I rotate them so they dry out. I find that the pads last longer when given a chance to dry, which is part of the fitting system.
Let's say you take a helmet into a shop, like I did a few years ago just to see what they would say. They didn't really inspect it, but they did ask how old it was. They recommended I replace it becuase it was over 5 years old. Why? Manufacturer's recommendation-the same guys that want to sell you a new helmet. And it was the right thing to do at the shop. To say otherwise might lead to a future lawsuit. I wonder if they would have inspected it if I said it was 2 years old. I'll try that experiment some other time.
I think what it ultimately gets down to is that it is difficult to accurate determine if a helmet's protection has been compromised. I've never had it done but I would presume it means taking a lot of measurements all over the helmet to determine the thickness of the foam (i.e. not compressed). It's such a pain to have done and to do, that in practice, it's just easier to replace on a schedule. Not perfect, I agree.
With respect to the legal issues with bike shops - I agree with you there too. The whole enshrinement of standards in law for helmet safety really seems like it locked the whole industry up on this sort of stuff. While it was done with good intentions, the unintended consequences have not been good.
J.
06-05-15 | 10:37 AM
#56
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2. It does seem sensible to warn silly billys not to pour petroleum products all over a Styrofoam product.
3. The last reason furnished "experience indicates there will be a noticeable improvement in the protective characteristic of helmets over a five-year period due to advances in materials, designs, production methods and the standards" is laughable.
Extract from Snell FAQ:
Why should you replace your helmet every five years?
The five-year replacement recommendation is based on a consensus by both helmet manufacturers and the Snell Foundation. Glues, resins and other materials used in helmet production can affect liner materials. Hair oils, body fluids and cosmetics, as well as normal "wear and tear" all contribute to helmet degradation. Petroleum based products present in cleaners, paints, fuels and other commonly encountered materials may also degrade materials used in many helmets possibly degrading performance. Additionally, experience indicates there will be a noticeable improvement in the protective characteristic of helmets over a five-year period due to advances in materials, designs, production methods and the standards. Thus, the recommendation for five-year helmet replacement is a judgment call stemming from a prudent safety philosophy.
06-05-15 | 10:40 AM
#57
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From: Minnesota
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Given your concern for "maximum effective protection" why do you allow anybody in your family to reuse a helmet with even a single "ding" or any physical evidence of "heavy use"?
Perhaps you might consider taking better care of your safety equipment, it might help you in your goal of maximum effective protection.
Perhaps you might consider taking better care of your safety equipment, it might help you in your goal of maximum effective protection.
06-05-15 | 10:51 AM
#58
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I bought a used Fox Flux helmet the other day. I like it and it's in great condition. It is replacing my former Giro helmet. This Fox helmet fits my head better and I notice the straps are routed through the helmet differently which puts the straps in a different position along the side of my face and ears. It's more comfortable and feels more stable.
My son had a cheap Giro helmet that we replaced last month. The helmet was cracking and falling apart. Clearly it wouldn't provide good protection in an accident. He had that helmet for around 5 years, coincidentally.
Now, I'm wondering, do the more expensive helmets last longer before they start falling apart due to age?
06-05-15 | 11:02 AM
#59
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From: NorCal
IMO the helmet protection band is fairly narrow within the possible outcomes from a fall or crash.
If we used the spectrum below as an example of all possible outcomes we might say that the green band is where the helmet makes a difference. The blues to the left represent those impacts where there would be little or no injury without a helmet, and the yellows and reds to the right impacts where the likely outcome is serious injury or death despite wearing a helmet.
Given that the band of protection is that narrow, small differences within that band are relatively less important. Keep in mind that bicycle helmets are designed with protection levels suitable for simple bicycle crashes, and not for crashes involving motor vehicles. So as a commuter, you face a reasonable likeliness that a crash will involve forces beyond the protection of any helmet.
This isn't to say that all helmets are equal, nor that wearing one is unjustified, but to offer some perspective so you may align your expectations to reality.
If we used the spectrum below as an example of all possible outcomes we might say that the green band is where the helmet makes a difference. The blues to the left represent those impacts where there would be little or no injury without a helmet, and the yellows and reds to the right impacts where the likely outcome is serious injury or death despite wearing a helmet.
Given that the band of protection is that narrow, small differences within that band are relatively less important. Keep in mind that bicycle helmets are designed with protection levels suitable for simple bicycle crashes, and not for crashes involving motor vehicles. So as a commuter, you face a reasonable likeliness that a crash will involve forces beyond the protection of any helmet.
This isn't to say that all helmets are equal, nor that wearing one is unjustified, but to offer some perspective so you may align your expectations to reality.
06-05-15 | 11:46 AM
#60
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The differences in infrastructure and overall danger is the reason to use the rate rather than any other number. You are roughly 9 times as likely to be involved in an injury/fatality crash riding a bicycle in the U.S. as in The Netherlands. But the types and percent of injuries are fairly consistent. Regardless of how many total crashes there are you'll have a relatively certain percent of broken collarbones, broken wrists, broken femurs, etc. The larger the sample the more consistent these become country to country. So for every 1,000 crashes you'll have about 70 broken collarbones and this will be consistent in the U.S. and NL and DM and DE and wherever. So while the infrastructure in The Netherlands reduces the total number of severe or fatal crashes it doesn't have much impact on the types of injuries sustained in those crashes.
The same happens with head trauma. For every 1,000 fatalities about 320 will involve TBI or Traumatic Brain Injury. It's actually a bit higher in the U.S., about 36% I believe, but this is not a significant difference. If helmets were effective then the number of TBI's per crash, the rate, would be significantly lower.
The same happens with head trauma. For every 1,000 fatalities about 320 will involve TBI or Traumatic Brain Injury. It's actually a bit higher in the U.S., about 36% I believe, but this is not a significant difference. If helmets were effective then the number of TBI's per crash, the rate, would be significantly lower.
If stats from the CDC aren't convincing then here's the first paragraph from the Institute for Road Safety Research in the Netherlands:
One third of the cyclists who are admitted to hospital with serious injury after a road crash are diagnosed with head or brain injury. Approximately three-quarters of the head and brain injuries among cyclists are caused by crashes that do not involve motorized traffic; as many as nine out of ten young children who sustain head/brain injury, do so in crashes not involving motor vehicles. These are mostly cyclist-only crashes. This type of crash is difficult to prevent, but it is possible to limit the severity of the head and brain injury by wearing a bicycle helmet. According to the most recent estimate (Elvik, 2011), the risk of sustaining head injury is 1.72 times higher for cyclists who do not wear a bicycle helmet than for the cyclists who do, with a 95% confidence interval of 1.33-3.45. For brain injury, the risk seems to be 2.13 times higher (with a confidence interval of 1.33-3.45). If all investigated head and neck injuries are considered together, the risk increase appears to be smaller but still present (factor of 1.18, 95% confidence interval: 1.02-1.35). Research in other countries has shown that the bicycle use sometimes decreases, particularly during the first few years after the introduction of mandatory helmet use. The longer-term effects or the significance of these results with regard to the situation in the Netherlands are not known.
You should really read the whole article. I think you would find it interesting. People in the Netherlands don't wear helmets because they don't want to. Just like no one wanted to wear seat belts when I was growing up. It's not because they don't work.
Again, I will state that if somebody is willing to accept the risks of not wearing a helmet that is their choice, but please don't try and talk people out of using one. The OP didn't ask whether they should wear a helmet or not. They asked which one to get.
The problem I have with these arguments is that people start with the conclusion: "I don't want to wear a helmet" and cherry pick stats that support that notion or perpetuate myths. Since this is a safety issue, I feel compelled to reply but discussions like this aren't often fruitful so I'm going to drop it.
Last edited by tjspiel; 06-05-15 at 12:00 PM.
06-05-15 | 12:34 PM
#61
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The differences in infrastructure and overall danger is the reason to use the rate rather than any other number. You are roughly 9 times as likely to be involved in an injury/fatality crash riding a bicycle in the U.S. as in The Netherlands. But the types and percent of injuries are fairly consistent. Regardless of how many total crashes there are you'll have a relatively certain percent of broken collarbones, broken wrists, broken femurs, etc. The larger the sample the more consistent these become country to country. So for every 1,000 crashes you'll have about 70 broken collarbones and this will be consistent in the U.S. and NL and DM and DE and wherever. So while the infrastructure in The Netherlands reduces the total number of severe or fatal crashes it doesn't have much impact on the types of injuries sustained in those crashes.
The same happens with head trauma. For every 1,000 fatalities about 320 will involve TBI or Traumatic Brain Injury. It's actually a bit higher in the U.S., about 36% I believe, but this is not a significant difference. If helmets were effective then the number of TBI's per crash, the rate, would be significantly lower.
The same happens with head trauma. For every 1,000 fatalities about 320 will involve TBI or Traumatic Brain Injury. It's actually a bit higher in the U.S., about 36% I believe, but this is not a significant difference. If helmets were effective then the number of TBI's per crash, the rate, would be significantly lower.
What "rate" are you addressing?
Regardless of how many total crashes there are the relative pattern of injuries are the same? - Only if you assume, as so many biased, self appointed bicycling risk experts do, that all bicycling crashes are considered equal, and that their injury severity results are also equal.
What percentage of NL's injury producing bicycle "crashes" involve collisions with motor vehicles vice those in the U.S.?
"Crashes" on relatively motor vehicle free bike paths, or sidewalks, or on splendid bicycle facilities will not likely produce the same patterns, percentages or severities of head injuries, broken collarbones, broken wrists, broken femurs, etc. as so-called bicycle "crashes" involving a motor vehicle. Unless your "rate" has been adjusted for involvement of motor vehicles in bicycle "crashes" both in the U.S. and NL it means nothing for evaluating helmet effectiveness.
Last edited by I-Like-To-Bike; 06-05-15 at 12:38 PM.
06-05-15 | 01:22 PM
#62
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From: Portland, OR
Bikes: It's complicated.
Bell: Bell has a general recommendation of replacing your helmet every three (3) years.
Giro: Giro has a general recommendation of replacing your helmet every three (3) years.
All are just recommendations. Where is the documentation to support this? Data?
Just to reiterate, there has been zero evidence (data) that supports swapping out helmets on a time basis, even a usage basis. I have stated that I get rid of a helmet when the "fitting" portions of the helmet start to break down-the foam inserts, the nylon webbing as it gets gunky and hard to adjust, the plastic adjustable thingie in the back, but never because I thought the expanded polystyrene was breaking down from age. Crash and your helmet hits the ground, chuck it, it's hard to quantify the reduction in thickness or see interior cracking. If use is making it hard to adjust or fit correctly on your head, chuck it.
06-05-15 | 01:43 PM
#63
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Bikes: It's complicated.
One could even argue that the most expensive helmets fall are apt to fall apart quicker, as they have more ventilation (more holes), structurally less strong than fewer holes. A current model Giro Aeon helmet suggested retail is $200.
The marketing: You wanted a lighter helmet, a cooler helmet, a better helmet—so we created one. Starting with a full roster of our best features, we optimized every component in the Aeon™ including the shape of the helmet itself, reducing weight by 28 percent compared with its predecessor. We also sculpted massive vents with interior channeling for best-in-class cooling power and integrated the adjustability and comfort of Roc Loc® 5, for a luxurious feel with all the performance you need.
The cheapest helmet I found using Google Shopping is under $10. It passes the same tests as the $200 helmet. If it fits you well, there's no safety reasoon not to buy it over the $200 helmet. You will find, however, that spending more gets you better adjustability, and fit is more important than any other factor. You may also find one helmet to have better ventilation than another. The last thing is looks: if you don't like the way it looks on you, you're less likely to wear it.
If more expensive helmets lasted longer than cheaper ones, wouldn't they advertise that?
06-05-15 | 01:44 PM
#64
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From: Portland, OR
Bikes: It's complicated.
The facility they are riding on is substandard by current Dutch standards and is not unusual in Denmark, Finland, or Sweden. In Denmark however there would be more bikes with front baskets, Finland doesn't use the black/white poles and they are rare in Denmark. About 1 in 50 people in Sweden wear a helmet so you'd likely see a helmet or two in a group this size. My guess is an older facility in Amsterdam or Rotterdam. There are few substandard facilities like this remaining outside of those two cities (and those like this that remain are disappearing quickly).
06-05-15 | 01:57 PM
#66
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06-05-15 | 02:03 PM
#67
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(original question --- Guess which US city the following picture is from
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Just because I'm tired of arguing, doesn't mean you're right.
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06-05-15 | 02:04 PM
#68
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From: Portland, OR
Bikes: It's complicated.
06-05-15 | 02:06 PM
#69
Bike Butcher of Portland
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From: Portland, OR
Bikes: It's complicated.
I keep pitching 'em up underhand, you guys keep swatting them out of the park...
06-05-15 | 06:39 PM
#70
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It's unfortunate that the CPSC standards were enshrined in law. They pretty much stopped a lot of safety innovation in helmets.
If you believe that the CPSC drop test on top of the helmet from a proscribed height translates into equivalent safety in all such rated helmets, then this is true. A helmet with more coverage of the head will protect from more intrusive injuries from aspects other than a straight down from the top. So it's not true that all CPSC helmets provide identical protection or performance. It is true that they all pass the same test. The question is whether that test is representative of what the helmet is actually called upon to do in real life. I don't think it is. In point of fact, I'd wonder if the test they use bears any real resemblance to even the most common hits that helmets take. Let's just say, I'm not impressed with the CPSC methodology or testing.
If you believe that the CPSC drop test on top of the helmet from a proscribed height translates into equivalent safety in all such rated helmets, then this is true. A helmet with more coverage of the head will protect from more intrusive injuries from aspects other than a straight down from the top. So it's not true that all CPSC helmets provide identical protection or performance. It is true that they all pass the same test. The question is whether that test is representative of what the helmet is actually called upon to do in real life. I don't think it is. In point of fact, I'd wonder if the test they use bears any real resemblance to even the most common hits that helmets take. Let's just say, I'm not impressed with the CPSC methodology or testing.
Therefore it appears that the 20 dollar helmet is equal to the 200 dollar helmet, at least in a controlled situation involving forces on the head. I don't know why you started talking about helmet penetration. I also don't know why you think my conclusion was based on the fact all the helmets passed the same test. Sure, everyone in a high school classroom passed 8th grade, but that sure as hell doesn't mean they're all academic equals.
06-05-15 | 06:50 PM
#71
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Furthermore, our son had a bad ski crash that resulted in a severe TBI. His helmet was obviously no longer any good based upon the crash that he experienced. However, fairly involved inspection of his helmet revealed no apparent damage other than that caused by first responders (cut chin strap). The only way to tell was to have the helmet examined by the manufactured to make sure that the foam had not been crushed significantly - in other words, the assessment tools and processes are pretty much out of the scope of being done by an end user.
----
The dichotomy of safe and unsafe being equivalent to helmeted vs. non-helmeted always manages to arise. Here's a thought experiment:
A cyclist goes down a hill with a helmet. He averages 40 mph downhill.
The same cyclist goes up the same hill the next day. Someone steals his helmet at the top because he left it with his bike while taking a bathroom break. Being cautious, he rides down but only at 15 mph. (Or hell, he walks his bike down the hill).
Can you think of any scenarios in which the helmeted cyclist loses while the non-helmeted cyclist wins? There exists a number of plausible scenarios in which having a helmet actually hurts the guy. Obviously there exists (probably a greater) number of plausible scenarios in which having a helmet helps the guy ... but wearing a helmet is not black&white; it's not safe vs. unsafe.
Last edited by Deontologist; 06-05-15 at 06:56 PM.
06-05-15 | 08:30 PM
#72
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From: New Jersey
Extract from Snell FAQ:
Why should you replace your helmet every five years?
The five-year replacement recommendation is based on a consensus by both helmet manufacturers and the Snell Foundation. Glues, resins and other materials used in helmet production can affect liner materials. Hair oils, body fluids and cosmetics, as well as normal "wear and tear" all contribute to helmet degradation. Petroleum based products present in cleaners, paints, fuels and other commonly encountered materials may also degrade materials used in many helmets possibly degrading performance. Additionally, experience indicates there will be a noticeable improvement in the protective characteristic of helmets over a five-year period due to advances in materials, designs, production methods and the standards. Thus, the recommendation for five-year helmet replacement is a judgment call stemming from a prudent safety philosophy.
Why should you replace your helmet every five years?
The five-year replacement recommendation is based on a consensus by both helmet manufacturers and the Snell Foundation. Glues, resins and other materials used in helmet production can affect liner materials. Hair oils, body fluids and cosmetics, as well as normal "wear and tear" all contribute to helmet degradation. Petroleum based products present in cleaners, paints, fuels and other commonly encountered materials may also degrade materials used in many helmets possibly degrading performance. Additionally, experience indicates there will be a noticeable improvement in the protective characteristic of helmets over a five-year period due to advances in materials, designs, production methods and the standards. Thus, the recommendation for five-year helmet replacement is a judgment call stemming from a prudent safety philosophy.
06-05-15 | 11:22 PM
#73
Bike Butcher of Portland
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From: Portland, OR
Bikes: It's complicated.
This paragraph reads like it came directly from the marketing department. These theories have no scientific basis at all. If Snell wanted to make their point, they should have taken 1,000 (or more) five year old helmets and conducted the same drop tests as their 2015 models. They probably did but guess what, the results did not warrant buying a new helmet hence no scientific study. As a result, their marketing department was given the job to increase new helmet sales.
The Snell Foundation doesn't sell helmets. They're not associated with any helmet manufacturers.
But the paragraph does read as marketing pablum.
Last edited by gugie; 06-05-15 at 11:26 PM. Reason: clarification
06-06-15 | 12:09 AM
#74
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From: Silicon Valley, CA
A helmet needs to FIT PROPERLY to be effective. When I was shopping for a helmet some joker at the LBS tried to convince me to purchase a helmet with was too large for my head. He insisted that it could be strapped down and the mechanism at the rear tightened. My head would have rattled around in that thing like a peanut in a walnut shell.
I do avoid helmets with points in the rear which have been called out as less desirable because the points can catch on things.
Helmets: Bicycle Helmets