View Poll Results: Helmet wearing habits?
I've never worn a bike helmet




178
10.66%
I used to wear a helmet, but have stopped




94
5.63%
I've always worn a helmet




648
38.80%
I didn't wear a helmet, but now do




408
24.43%
I sometimes wear a helmet depending on the conditions




342
20.48%
Voters: 1670. You may not vote on this poll
The helmet thread
#7226
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In the safety profession, we use what is called the Hierarchy of Controls.
John, what is the incidence of those falls in which a hemet my be beneficial? Such a incidents per cyclist miles, or chance per ride, or any other measure you can find. If the incidence is sufficiently low, the the cost per averted injury os prohibitive or unreasonable.
In any respectable Risk Management Program, the various potential hazards are considered and evaluated for their relative risk, be it financial or safety related, BEFORE various controls are considered. When hazards are evaluated as having an insignificant risk value (probability of event x likely severity of event,) seldom are controls considered necessary or even desirable. This is especially true where controls with negative effects on the desired activity /or with debatable capability in reducing the risk value, especially a hazard evaluated as having an already very low risk value.
Last edited by I-Like-To-Bike; 03-19-14 at 09:14 PM.

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Howsteepisit has asked the exactly correct question. Mr. Ratliff insists on placing the cart before the horse.
In any respectable Risk Management Program, the various potential hazards are considered and evaluated for their relative risk, be it financial or safety related, BEFORE various controls are considered. When hazards are evaluated as having an insignificant risk value (probability of event x likely severity of event,) seldom are controls considered necessary or even desirable. This is especially true where controls with negative effects on the desired activity /or with debatable capability in reducing the risk value, especially a hazard evaluated as having an already very low risk value.
emphasis added, jcr
In any respectable Risk Management Program, the various potential hazards are considered and evaluated for their relative risk, be it financial or safety related, BEFORE various controls are considered. When hazards are evaluated as having an insignificant risk value (probability of event x likely severity of event,) seldom are controls considered necessary or even desirable. This is especially true where controls with negative effects on the desired activity /or with debatable capability in reducing the risk value, especially a hazard evaluated as having an already very low risk value.
emphasis added, jcr

From ANSI Z10-2005, American National Standard for Occupational Safety and Health Management Systems
Note that falling off a bike would be an occasional happening, so the frequency would be "Occasional," with a Liklihood rating of 3. The Severity rating would be either a 3 or 4 (with the potential of disability of greater than 3 months, a permanent disability, or death). This gets a "High" or "Serious" rating, with the designation "Operations not Permissible" or "High Priority Remedial Action." For bicycling, training, equipping the bike correctly, fitting it, and PPE (helmet) are indicated.
I'll go into Howsteepitis' question later.
John

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"Note that falling off a bike would be an occasional happening, so the frequency would be "Occasional," with a Liklihood rating of 3. The Severity rating would be either a 3 or 4 (with the potential of disability of greater than 3 months, a permanent disability, or death). This gets a "High" or "Serious" rating, with the designation "Operations not Permissible" or "High Priority Remedial Action." For bicycling, training, equipping the bike correctly, fitting it, and PPE (helmet) are indicated."
Do you still bicycle John? If I agreed with your assessment of the risk and likely severity I would quit immediately. And that's what the chart says - if you think a simple fall with 'occasional' likelihood merits a severity rating as high as 4 then that activity is "Not Permissible."
But in my experience in about 60 years of cycling and hundreds of thousands of miles I have personally had a few falls and have observed quite a few happen to others on group rides. Only one of these incidents involved any hospitalization (just for observation) and therefore might warrant a severity of 2; all the others were either self-treated or first aid given by EMTs/ERs and released for a severity rating of 1.
I've also seen one more serious injury (sev. 3), but that was a result of a direct impact with a motor vehicle which is a much less likely event than a simple fall. Overall my assessment would put bicycling somewhere between the 'Remedial Action Discretionary' and 'Take action at appropriate time' categories.
That's certainly not to say that a simple fall might not have a more serious outcome - clearly it might. But the likelihood of such a serious outcome is quite low and takes it out of the 'occasional - likely to occur' category.
Do you still bicycle John? If I agreed with your assessment of the risk and likely severity I would quit immediately. And that's what the chart says - if you think a simple fall with 'occasional' likelihood merits a severity rating as high as 4 then that activity is "Not Permissible."
But in my experience in about 60 years of cycling and hundreds of thousands of miles I have personally had a few falls and have observed quite a few happen to others on group rides. Only one of these incidents involved any hospitalization (just for observation) and therefore might warrant a severity of 2; all the others were either self-treated or first aid given by EMTs/ERs and released for a severity rating of 1.
I've also seen one more serious injury (sev. 3), but that was a result of a direct impact with a motor vehicle which is a much less likely event than a simple fall. Overall my assessment would put bicycling somewhere between the 'Remedial Action Discretionary' and 'Take action at appropriate time' categories.
That's certainly not to say that a simple fall might not have a more serious outcome - clearly it might. But the likelihood of such a serious outcome is quite low and takes it out of the 'occasional - likely to occur' category.

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Stop right there. Falling off a bike is an occasional happening? Really? I'm more likely to fall off my chair than my bike (angular momentum and all that). Falling off a bike is an incredibly rare event for normal people, at least in my experience. Where do you get the impression that falling off a bike happens so frequently?

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Something like this:
Note that falling off a bike would be an occasional happening, so the frequency would be "Occasional," with a Liklihood rating of 3. The Severity rating would be either a 3 or 4 (with the potential of disability of greater than 3 months, a permanent disability, or death). This gets a "High" or "Serious" rating, with the designation "Operations not Permissible" or "High Priority Remedial Action." For bicycling, training, equipping the bike correctly, fitting it, and PPE (helmet) are indicated.
I'll go into Howsteepitis' question later.
John
Note that falling off a bike would be an occasional happening, so the frequency would be "Occasional," with a Liklihood rating of 3. The Severity rating would be either a 3 or 4 (with the potential of disability of greater than 3 months, a permanent disability, or death). This gets a "High" or "Serious" rating, with the designation "Operations not Permissible" or "High Priority Remedial Action." For bicycling, training, equipping the bike correctly, fitting it, and PPE (helmet) are indicated.
I'll go into Howsteepitis' question later.
John
First. Every "falling off a bike" event does not result in the head striking an object. The likelihood probability of falling off a bike has to multiplied by the probability of striking the head against a hard object. And that probability has to be multiplied by the probability that the head strikes an object with enough force to cause injury. Far less than your exaggerated probability of occasionally.
Second, in the remote to improbable chance that a cyclist falls off a bike AND strikes the head, the likelihood that such a strike will create an injury with greater severity than marginal or negligible is even more remote or improbable.
Third, recommending (or expecting that) a bicycle helmet will "control" or reduce the injury severity of an event capable of causing catastrophic or critical head injuries to marginal or negligible is ridiculous and is dependent on this "control" performing far beyond its design limitation and specifications.

#7231
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I get debiked or purposely debiked at least a couple times a year, usually while mountain biking. I've been down 3 times in the last 6 months. Once in a STXC race, once while single track riding once while trail riding on a drop bar MTB. Was helmeted for all 3 of those but didn't even scratch my lid. It really is pretty difficult to crash on your head.
Once I rode across a crosswalk late on the light and got clipped be a car that was pacing the lights. Tagged my rear wheel @ 40 + mph and sent me flying 20'. No head impact but my Huffy 10 speed was toast.
After lots of riding and lots of crashing I feel careful road riding has similar head impact probability to that of jogging.
Once I rode across a crosswalk late on the light and got clipped be a car that was pacing the lights. Tagged my rear wheel @ 40 + mph and sent me flying 20'. No head impact but my Huffy 10 speed was toast.
After lots of riding and lots of crashing I feel careful road riding has similar head impact probability to that of jogging.
Last edited by LesterOfPuppets; 03-20-14 at 12:28 AM.

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I am not sure that comparing bicycling risk to occupational risk programs is a good idea either. OSHA is not a regulatory body who's standards should apply to bicycling, nor should ANSI Z10 be applicable. IF it were as John surmises, since death is possible on occasional occurrence the activity should be prohibited. Maybe John would like to rethink his analysis?
Last edited by howsteepisit; 03-20-14 at 02:10 AM.

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lester
FYI I fly TWO flags on my trike.
To all the helmet nay sayers, all of your silly personal attacks are meaningless to me. IMO they are little more than a tacit admission you have nothing to add to the debate. Personal attacks pretty much indicates you have lost.
FYI I fly TWO flags on my trike.
To all the helmet nay sayers, all of your silly personal attacks are meaningless to me. IMO they are little more than a tacit admission you have nothing to add to the debate. Personal attacks pretty much indicates you have lost.

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#7236
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It is interesting to me that all you nay-sayers on helmets can offer is a personal attack. No, I won't re-analyze the risk assessment, as that is how a risk for a situation is done by safety professionals. We look at worst case potential injuries, not the scenario whereby someone comes unscathed by a situation where injury should occur; these are called "near miss" situations, and safety professionals treat these as if they had produced an injury, so as to prevent it the next during the next occurrence.
You also need to understand that you are the top bracket of cyclists, and your experience does not represent that of the majority of cyclists. The Portland Bureau of Transportation's Bike Master Plan breaks down bicycle riders into these categories:
--Strong and Fearless – will ride regardless of road accommodations for bikes; trip distance is not an issue.
--Enthused and Confident – Comfortable in traffic with appropriate accommodations for bikes; prefers shorter trip distances.
--Interested but Concerned – Not comfortable in traffic, nor attracted to bike lanes; prefers to ride in areas with low traffic volumes and speed.
--No Way No How – Not interested in using a bike for transportation.
You are in the Strong and Fearless category.
Some of you have been posting here for many years (hi, Lesterofpuppets and I-Like-To-Bike). You do not use your actual names; you have no "skin" in these discussions due to your being anonymous. So you can say anything you want without consequence, except that some read these posts and assume you know what you are talking about, when many of these posts are very far from the scientific information available. A good example is this post by howsteepitis:
Now, this post shows a lack of research into the available information out there. If you had done some research, rather than just picking up your calculator and making a very biased calculation, you would know that the one-year lifetime costs of bicycle injuries and fatalities has been calculated to be $5,488,000,000 for 2005 (Rebecca B. Naumann, et. al., Incidence and Total Lifetime Costs of Motor Vehicle-Related Fatal and Nonfatal Injury by Road User Type, United States, 2005).
If we took your calculation (based on nebulous numbers) of the costs of helmets at $709,000,000, you would see that this is only 12.9% of the lifetime costs of those injuries for 2005.
If we look at the range of risk abatement costs, and look at the range of expected losses, the range of possible optima for abatement of about 13% is within that set of preferences. (Kammen, Daniel M., and David M. Hassenzahl, Should We Risk It?, Exploring Envinronmental, Health, and Technological Problem Solving, Princeton University Press, Prinston and Oxford, 1999, page 15.) But this number concerning injury and fatality costs is for only one year (2005), and the people who would receive these helmets can keep them for a longer time. If only 25% of these costs were prevented, it would still remain within the acceptable abatement costs for a return-on-investment.
However, the bicycle helmet is low on the Hierarchy of Controls; what is needed is better planning and development for bicycle facilities. So I have a couple of challenges for you who have posted for years here. If you are not already, get involved in your community planning for bicycle transportation issues. Also, if you have no health insurance, please sign up for the Affordable Care Act before the end of the month.
John
You also need to understand that you are the top bracket of cyclists, and your experience does not represent that of the majority of cyclists. The Portland Bureau of Transportation's Bike Master Plan breaks down bicycle riders into these categories:
--Strong and Fearless – will ride regardless of road accommodations for bikes; trip distance is not an issue.
--Enthused and Confident – Comfortable in traffic with appropriate accommodations for bikes; prefers shorter trip distances.
--Interested but Concerned – Not comfortable in traffic, nor attracted to bike lanes; prefers to ride in areas with low traffic volumes and speed.
--No Way No How – Not interested in using a bike for transportation.
You are in the Strong and Fearless category.
Some of you have been posting here for many years (hi, Lesterofpuppets and I-Like-To-Bike). You do not use your actual names; you have no "skin" in these discussions due to your being anonymous. So you can say anything you want without consequence, except that some read these posts and assume you know what you are talking about, when many of these posts are very far from the scientific information available. A good example is this post by howsteepitis:
Well, the value of a statistical life use by DOT is $6mm. According to NHSTA 18% of persons over the age of 18 took at least one bike ride in the summer of 2012, and the US Census reports the population of that group to be $197mm. If each of those 18% bought a helmet for $20, my calculations are that it costs $709mm to save at least one $6mm life.
Thats coldly logical.
Thats coldly logical.
If we took your calculation (based on nebulous numbers) of the costs of helmets at $709,000,000, you would see that this is only 12.9% of the lifetime costs of those injuries for 2005.
If we look at the range of risk abatement costs, and look at the range of expected losses, the range of possible optima for abatement of about 13% is within that set of preferences. (Kammen, Daniel M., and David M. Hassenzahl, Should We Risk It?, Exploring Envinronmental, Health, and Technological Problem Solving, Princeton University Press, Prinston and Oxford, 1999, page 15.) But this number concerning injury and fatality costs is for only one year (2005), and the people who would receive these helmets can keep them for a longer time. If only 25% of these costs were prevented, it would still remain within the acceptable abatement costs for a return-on-investment.
However, the bicycle helmet is low on the Hierarchy of Controls; what is needed is better planning and development for bicycle facilities. So I have a couple of challenges for you who have posted for years here. If you are not already, get involved in your community planning for bicycle transportation issues. Also, if you have no health insurance, please sign up for the Affordable Care Act before the end of the month.
John
Last edited by John C. Ratliff; 03-20-14 at 04:08 PM.

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I will look at the annual cost, but I'd bet that the costs saved by increased helmet use would be very low. I do note that of the specified categories of lifetime user costs, pedal cyclists is the lowest, including pedestrians. So perhaps helmet technology is better utilized elsewhere?
And no, I don't think my reading os the ANSI risk table that you provided is incorrect, by your analysis, bicycling would fall into the occasional occurrence, catastrophic consequence category, regardless of the use of protective headgear or not. Therefore, the activity is occupationally unacceptable by your analysis and selected methods of evaluation. I disagree because I do not find bicycling to carry an unacceptable risk.
But in the bottom line John, How much is a helmet worth to you? If you lost yours, how much would you be willing to pay to replace it? Mine value would be quite low, as I believe the insurance value of bicycle helmets is quite low. Yours is higher. Thats OK, but my main disagreement is with those who insist on telling me to wear a helmet.
We are in agreement that there are much better ways to mitigate the risks in cycling, but we seem to disagree how much risk there actually is.
And no, I don't think my reading os the ANSI risk table that you provided is incorrect, by your analysis, bicycling would fall into the occasional occurrence, catastrophic consequence category, regardless of the use of protective headgear or not. Therefore, the activity is occupationally unacceptable by your analysis and selected methods of evaluation. I disagree because I do not find bicycling to carry an unacceptable risk.
But in the bottom line John, How much is a helmet worth to you? If you lost yours, how much would you be willing to pay to replace it? Mine value would be quite low, as I believe the insurance value of bicycle helmets is quite low. Yours is higher. Thats OK, but my main disagreement is with those who insist on telling me to wear a helmet.
We are in agreement that there are much better ways to mitigate the risks in cycling, but we seem to disagree how much risk there actually is.
Last edited by howsteepisit; 03-20-14 at 03:58 PM.

#7238
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...it's been years since anyone called me strong and fearless.

__________________

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It is interesting to me that all you nay-sayers on helmets can offer is a personal attack. No, I won't re-analyze the risk assessment, as that is how a risk for a situation is done by safety professionals. We look at worst case potential injuries, not the scenario whereby someone comes unscathed by a situation where injury should occur; these are called "near miss" situations, and safety professionals treat these as if they had produced an injury, so as to prevent it the next during the next occurrence.
No reputable safety professional builds a risk analysis on the worst case potential injuries, if they did, the hazard of paper cut injuries would be evaluated based on an infection-gangrene-amputation scenario and clerks would be required to wear steel mesh gloves as a "control" to handle every piece of paper. Your immediate dodge of crying personal insult leaves me to believe there is little to be gained in reading your stuff.
I did read the rest before posting and there is nothing but more smoke and mirror flimflam dressed up in Safety Professional Speak, none of which supports your so-called Safety professional-like risk analysis of bicycling injuries and the value of bicycle helmets to mitigate risk.
Your wacky bit about other posters having less credence than you because they do not choose to use their given name as a moniker on BF like you just demonstrates how desperate for attention you must be to grab at such a rhetorical straw.
I consider you and rydabent as two sides of the same coin, committed to a belief in the power of helmets to protect cyclists from worst case scenarios and every lesser collision as well, come hell or high water, regardless of any facts or evidence.

#7240
Senior Member
You will note that PPE (personal protective equipment, such as a bicycling helmet), is at the bottom of these controls. It is the least effective of the hierarchy of controls.
“risk compensation” does occur in adults, and probably in kids too.
Yes, bicyclists can and do ride without helmets, but in the case of a fall, numerous studies (see the link for one recent one) have shown the efficacy of bicycle helmets in preventing substantial head injures that can be fatal.
PS--I was able to add files from my trip to Hong Kong.
“risk compensation” does occur in adults, and probably in kids too.
Yes, bicyclists can and do ride without helmets, but in the case of a fall, numerous studies (see the link for one recent one) have shown the efficacy of bicycle helmets in preventing substantial head injures that can be fatal.
PS--I was able to add files from my trip to Hong Kong.
2. The fact that risk compensation does occur supports my assertion. Although the study you cite is far from comprehensive. It is interesting that those who usually do not wear helmets do not ride less safe with them, but it also seems to indicate that those who wear helmets on a regular basis are riding less safe because of them.
3. Here's a significant excerpt from the abstract you linked to:
Originally Posted by McNally & Whitehead
Bicycle helmets were found to be effective in reducing the severity of head injuries sustained in common accidents. They reduced the risk of an AIS>3 injury, in cases with head impacts, by an average of 40%. In accidents that would cause up to moderate (AIS=2) injuries to a non-helmeted rider, helmets eliminated the risk of injury. Helmets were also found to be effective in preventing fatal head injuries in some instances. The effectiveness of helmets was demonstrated over the entire range of cycle speeds studied, up to and including 14 m s(-1). There was no evidence that helmet wearing increased the risk of neck injury, indeed helmets were found to be protective of neck injuries in many cases. Similarly, helmets were found to offer an increase in protection even when an increase in cycle speed due to risk compensation was taken into consideration
- The AIS>3 / 40% line. That's great, but the AIS scale goes up to 9. I'm sure helmets help with injury on the lesser end of the scale, but I wonder how effective they are at the higher injury levels, which occur due to forces far in excess of what helmets are designed for. That the authors chose to word it as they do might indicate bias.
- "Helmets were also found to be effective in preventing fatal head injuries in some instances." is qualitatively different than your statement "...efficacy of bicycle helmets in preventing substantial head injures that can be fatal."
While I draw different conclusions than you do, I'm interested to hear what the bare-headers have to say about the study, because there's some pretty conclusively damning results in there which support helmet use.
4. I've been to Hong Kong. I didn't see any cycling infrastructure at all in the part of the city where we stayed and I walked around quite a bit, saw many different parts of the city via subway. I would not consider HK a safe cycling mecca, and very few riders wear helmets.
Bottom line is you've still only addressed one of the three issues I raised when claiming helmets make riding less safe, and in fact found support for one of them...

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This is the point where I copy and paste all the personal attacks you have made on this thread over the years. Except that 1) it's unnecessary, because we all know about them already, and B) it wouldn't get through to you anyway.

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Between the fact that numerous people here critiqued your argument, and the fact that you ended your very first post of your recent return to this thread with a completely uncalled-for personal attack, that's just a really weird thing to have written.

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I-Like-To-Bike, you state, "I may or may not even read the rest of the post since you begin with more double helpings of prime baloney.
No reputable safety professional builds a risk analysis on the worst case potential injuries..." Ever done a Process Safety Management (PSM) Process Hazard Analysis (this is a document download, so don't expect a URL to appear):
Factsheet #8
The Case for Worst-case Scenarios
Some companies consider only worst-credible scenarios rather than looking at the much more extreme worst-case scenarios. They argue that worst-case incidents are so improbable that they are virtual impossibilities. However, experience with numerous chemical industry disasters has shown that what was thought to be impossible happens all too often.
The Environmental Protection Agency requires many PSM-covered facilities to develop Risk Management Plans that include worst-case assessments of hazardous processes. These assessments must assume that all back-up safety systems have failed to work. Their examples include:
A transfer hose with no shutoffs fails, resulting in the release of the contents of the vessel or tank it is attached to;
Tank piping with no shutoffs fails, resulting in the total release of the tank contents;
A flame impingement on a vessel which results in the vessel’s failing; and
A severe vessel over-pressurization caused by contamination, a runaway reaction, or overheating which causes a venting to the atmosphere or a vessel failure.
The Case for Worst-case Scenarios
Some companies consider only worst-credible scenarios rather than looking at the much more extreme worst-case scenarios. They argue that worst-case incidents are so improbable that they are virtual impossibilities. However, experience with numerous chemical industry disasters has shown that what was thought to be impossible happens all too often.
The Environmental Protection Agency requires many PSM-covered facilities to develop Risk Management Plans that include worst-case assessments of hazardous processes. These assessments must assume that all back-up safety systems have failed to work. Their examples include:
A transfer hose with no shutoffs fails, resulting in the release of the contents of the vessel or tank it is attached to;
Tank piping with no shutoffs fails, resulting in the total release of the tank contents;
A flame impingement on a vessel which results in the vessel’s failing; and
A severe vessel over-pressurization caused by contamination, a runaway reaction, or overheating which causes a venting to the atmosphere or a vessel failure.
That is why I use worst-case scenarios in the assessment of a bicycle fall. It is only chance which determines whether there is a head impact during these mishaps, so that potential must be considered.
Mconlonx,
We share a lot of the same things, but you are asking me to do things that you should be doing for yourself. I have posted in the past many, many studies (ask Six jours), so if you want to see them, do a search on these threads of my name and take a look. Here is one I just uncovered:
CMAJ. 2012 Nov 20;184(17):E921-3. doi: 10.1503/cmaj.120988. Epub 2012 Oct 15.
Nonuse of bicycle helmets and risk of fatal head injury: a proportional mortality, case-control study.
Persaud N1, Coleman E, Zwolakowski D, Lauwers B, Cass D.
Author informationAbstract
BACKGROUND:
The effectiveness of helmets at preventing cycling fatalities, a leading cause of death among young adults worldwide, is controversial, and safety regulations for cycling vary by jurisdiction. We sought to determine whether nonuse of helmets is associated with an increased risk of fatal head injury.
METHODS:
We used a case-control design involving 129 fatalities using data from a coroner's review of cycling deaths in Ontario, Canada, between 2006 and 2010. We defined cases as cyclists who died as a result of head injuries; we defined controls as cyclists who died as a result of other injuries. The exposure variable was nonuse of a bicycle helmet.
RESULTS:
Not wearing a helmet while cycling was associated with an increased risk of dying as a result of sustaining a head injury (adjusted odds ratio [OR] 3.1, 95% confidence interval [CI] 1.3-7.3). We saw the same relationship when we excluded people younger than 18 years from the analysis (adjusted OR 3.5, 95% CI 1.4-8.5) and when we used a more stringent case definition (i.e., only a head injury with no other substantial injuries; adjusted OR 3.6, 95% CI 1.2-10.2).
INTERPRETATION:
Not wearing a helmet while cycling is associated with an increased risk of sustaining a fatal head injury. Policy changes and educational programs that increase the use of helmets while cycling may prevent deaths.
Nonuse of bicycle helmets and risk of fatal head injury... [CMAJ. 2012] - PubMed - NCBI
Nonuse of bicycle helmets and risk of fatal head injury: a proportional mortality, case-control study.
Persaud N1, Coleman E, Zwolakowski D, Lauwers B, Cass D.
Author informationAbstract
BACKGROUND:
The effectiveness of helmets at preventing cycling fatalities, a leading cause of death among young adults worldwide, is controversial, and safety regulations for cycling vary by jurisdiction. We sought to determine whether nonuse of helmets is associated with an increased risk of fatal head injury.
METHODS:
We used a case-control design involving 129 fatalities using data from a coroner's review of cycling deaths in Ontario, Canada, between 2006 and 2010. We defined cases as cyclists who died as a result of head injuries; we defined controls as cyclists who died as a result of other injuries. The exposure variable was nonuse of a bicycle helmet.
RESULTS:
Not wearing a helmet while cycling was associated with an increased risk of dying as a result of sustaining a head injury (adjusted odds ratio [OR] 3.1, 95% confidence interval [CI] 1.3-7.3). We saw the same relationship when we excluded people younger than 18 years from the analysis (adjusted OR 3.5, 95% CI 1.4-8.5) and when we used a more stringent case definition (i.e., only a head injury with no other substantial injuries; adjusted OR 3.6, 95% CI 1.2-10.2).
INTERPRETATION:
Not wearing a helmet while cycling is associated with an increased risk of sustaining a fatal head injury. Policy changes and educational programs that increase the use of helmets while cycling may prevent deaths.
Nonuse of bicycle helmets and risk of fatal head injury... [CMAJ. 2012] - PubMed - NCBI
John
Last edited by John C. Ratliff; 03-20-14 at 11:37 PM.

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You also need to understand that you are the top bracket of cyclists, and your experience does not represent that of the majority of cyclists. The Portland Bureau of Transportation's Bike Master Plan breaks down bicycle riders into these categories:
--Strong and Fearless – will ride regardless of road accommodations for bikes; trip distance is not an issue.
--Enthused and Confident – Comfortable in traffic with appropriate accommodations for bikes; prefers shorter trip distances.
--Interested but Concerned – Not comfortable in traffic, nor attracted to bike lanes; prefers to ride in areas with low traffic volumes and speed.
--No Way No How – Not interested in using a bike for transportation.
You are in the Strong and Fearless category.
Now, this post shows a lack of research into the available information out there. If you had done some research, rather than just picking up your calculator and making a very biased calculation, you would know that the one-year lifetime costs of bicycle injuries and fatalities has been calculated to be $5,488,000,000 for 2005 (Rebecca B. Naumann, et. al., Incidence and Total Lifetime Costs of Motor Vehicle-Related Fatal and Nonfatal Injury by Road User Type, United States, 2005).

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I-Like-To-Bike, you state, "I may or may not even read the rest of the post since you begin with more double helpings of prime baloney.
No reputable safety professional builds a risk analysis on the worst case potential injuries..." Ever done a Process Safety Management (PSM) Process Hazard Analysis (this is a document download, so don't expect a URL to appear):
We specifically have to make worst-case assessments, and these must be communicated to the community and emergency responders. So I don't know where you are getting your information, but it is not correct.
That is why I use worst-case scenarios in the assessment of a bicycle fall. It is only chance which determines whether there is a head impact during these mishaps, so that potential must be considered.
No reputable safety professional builds a risk analysis on the worst case potential injuries..." Ever done a Process Safety Management (PSM) Process Hazard Analysis (this is a document download, so don't expect a URL to appear):
We specifically have to make worst-case assessments, and these must be communicated to the community and emergency responders. So I don't know where you are getting your information, but it is not correct.
That is why I use worst-case scenarios in the assessment of a bicycle fall. It is only chance which determines whether there is a head impact during these mishaps, so that potential must be considered.
What a reputable hazard analysis must take into account when determining the likely results of a hazard are the credible probabilities of various types of injury severity that would result from various events. Not just the worst case scenario; this is not a chemical plant or nuclear reactor being evaluated.
Equally damning of your so-called hazard analysis is that your suggested control, the wear of a helmet, has little to no capability to mitigate the severity of the worst case scenarios, or even the fair to middling type injury severities likely to result from bicycle fall events.

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Originally Posted by John C. Ratliff
...You also need to understand that you are the top bracket of cyclists, and your experience does not represent that of the majority of cyclists. The Portland Bureau of Transportation's Bike Master Plan breaks down bicycle riders into these categories:
--Strong and Fearless – will ride regardless of road accommodations for bikes; trip distance is not an issue.
--Enthused and Confident – Comfortable in traffic with appropriate accommodations for bikes; prefers shorter trip distances.
--Interested but Concerned – Not comfortable in traffic, nor attracted to bike lanes; prefers to ride in areas with low traffic volumes and speed.
--No Way No How – Not interested in using a bike for transportation.
You are in the Strong and Fearless category.
--Strong and Fearless – will ride regardless of road accommodations for bikes; trip distance is not an issue.
--Enthused and Confident – Comfortable in traffic with appropriate accommodations for bikes; prefers shorter trip distances.
--Interested but Concerned – Not comfortable in traffic, nor attracted to bike lanes; prefers to ride in areas with low traffic volumes and speed.
--No Way No How – Not interested in using a bike for transportation.
You are in the Strong and Fearless category.
How many of those dollars are spent on children learning to ride? They aren't really germane to a discussion of adult helmet use.
‘Strong and fearless’ bicyclists (about 1 or 2 percent) will ride anywhere, regardless of the bicycle facility or lack thereof. They are comfortable on busy roads without bike lanes and may - in many circumstances - prefer to have no bicycle facilities at all.
Concerning your last question, I think you are talking about this part of the quote:
Now, this post shows a lack of research into the available information out there. If you had done some research, rather than just picking up your calculator and making a very biased calculation, you would know that the one-year lifetime costs of bicycle injuries and fatalities has been calculated to be $5,488,000,000 for 2005 (Rebecca B. Naumann, et. al., Incidence and Total Lifetime Costs of Motor Vehicle-Related Fatal and Nonfatal Injury by Road User Type, United States, 2005).
John
Last edited by John C. Ratliff; 03-21-14 at 01:23 AM.

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More helping of baloney. Nobody needs a hazard analysis of any kind to understand that a worst case scenario of a fatal head injury could occur after a "bicycle fall." No community needs you to communicate your Henny Penny warnings of the worst case scenario "You could Die!!" dressed up as a Hazard Analysis, anymore than they need a rydabent type giving the same shrill alarms without the facade of allegedly serious thought given the subject.
What a reputable hazard analysis must take into account when determining the likely results of a hazard are the credible probabilities of various types of injury severity that would result from various events. Not just the worst case scenario; this is not a chemical plant or nuclear reactor being evaluated.
Equally damning of your so-called hazard analysis is that your suggested control, the wear of a helmet, has little to no capability to mitigate the severity of the worst case scenarios, or even the fair to middling type injury severities likely to result from bicycle fall events.
What a reputable hazard analysis must take into account when determining the likely results of a hazard are the credible probabilities of various types of injury severity that would result from various events. Not just the worst case scenario; this is not a chemical plant or nuclear reactor being evaluated.
Equally damning of your so-called hazard analysis is that your suggested control, the wear of a helmet, has little to no capability to mitigate the severity of the worst case scenarios, or even the fair to middling type injury severities likely to result from bicycle fall events.
I used to think the same way, that doing a good judo roll could get me out of most situations. But that was a few decades ago, and a couple of trips to the hospital as the result of being T-boned and cut off tell me a different story. What to you is incredible, to me is credible...because it has happened to me. Not recently, but that is the result of a lot of thinking and soul-searching about how I was riding, and throwing out some concepts that had previously learned about bicycle commuting.
My suggestion, if you'll read closely, was three-fold: 1) training in use of a bicycle, 2) ensuring that the bicycle is operable (in good shape, mechanically), and 3) use of a helmet while riding. Check (I'm not going to take the time right now) but I think it was in that order too.
John

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Mconlonx,
We share a lot of the same things, but you are asking me to do things that you should be doing for yourself.
You apparently stayed in either the Hong Kong Island side, or Kowloon near the center of the city. There is much more to Hong Kong than those areas.
We share a lot of the same things, but you are asking me to do things that you should be doing for yourself.
You apparently stayed in either the Hong Kong Island side, or Kowloon near the center of the city. There is much more to Hong Kong than those areas.
You seem to be having a different argument that the one I put forth. I'm arguing that helmet use has a net negative effect on cycling safety; you are arguing that helmets have a net positive effect regarding injury. I'll gladly concede -- have in the past, doing so here now, will in the future -- that helmets do protect from and mitigate some injury in the case of a bicycle crash where a headstrike occurs. But you still have not addressed the broader implications on safety.
HK Island side indeed. And mainland China -- Shenzhen, Dongguan, Guangzhou, etc. Lots of bicycle riders. Few helmets -- single digits in a sample of many hundreds observed.

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It is my understanding that Process Safety Management Plans, which if I recall were a development to end massive threats to public health and safety such as the Bhopal India disaster have any applicability to bicycle helmets? My gaseous emissions are limited to the aftereffects of bean dinners and we just will not go to the process pressure vessel part of my anatomy. Using the principles of Process Safety Planning to justify bicycle helmet use is a far reach.

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It is my understanding that Process Safety Management Plans, which if I recall were a development to end massive threats to public health and safety such as the Bhopal India disaster have any applicability to bicycle helmets? My gaseous emissions are limited to the aftereffects of bean dinners and we just will not go to the process pressure vessel part of my anatomy. Using the principles of Process Safety Planning to justify bicycle helmet use is a far reach.
Originally Posted by I-Like-To-Bike
"I may or may not even read the rest of the post since you begin with more double helpings of prime baloney.
No reputable safety professional builds a risk analysis on the worst case potential injuries..."
No reputable safety professional builds a risk analysis on the worst case potential injuries..."
John
