Posts Tagged ‘helmets’
On Tuesday morning, the Environmental Matters Committee of the Maryland House of Delegates will hold a hearing on House Bill 339 to require that every person operating a bicycle in Maryland wear a helmet. This bill is bad policy.
Mandatory helmet laws cause fewer people to bicycle, and when fewer people bicycle, cycling becomes less safe. So much less safe, in fact, that decreased ridership increases the individual cyclist’s risk of injury more than wearing a helmet decreases risk of injury.
This does not mean that bicyclists should not wear helmets. We encourage bicyclists to wear helmets. However, there are several reasons why people who are deeply committed to bicyclist safety oppose mandatory helmet laws.
Mandatory helmet laws decrease ridership
Numerous studies of places that have enacted helmet laws have shown this to be true. The most commonly-cited study—Dorothy Robinson’s “No Clear Evidence from Countries that have Enforced the Wearing of Helmets”—examined data from New Zealand, from Nova Scotia, Canada, and from several states in Australia. In each place, the mandatory helmet law significantly decreased ridership, from 20% to 44% with an average of 37.5%.
(One can debate whether Maryland can expect a decrease of this magnitude. There is no local data available, so this analysis uses the average of 37.5%. But even if the decrease is only 20%, the lowest Robinson observed, even half of that, the result is the same.)
Lower ridership makes bicycling less safe.
We are defining “safety” as the likelihood of a bike-auto crash. By saying that decreased ridership makes bicycling less safe, we mean that a decreased rate of bicycling within a population is correlated with increased crash rates, and vice versa.
The leading article on this topic—Peter Jacobsen’s “Safety in Numbers: More Walkers and Bicyclists, Safer Walking and Bicycling“—reviews data on biking, walking, and injury rates in 68 California cities, 47 Danish towns, 14 European countries, and the United Kingdom.
Across the independent sets of data from these many jurisdictions, Jacobsen finds a consistent, inverse, curvilinear relationship between bicycling and injury rates, determining that “the total number of pedestrians or bicyclists struck by motorists varies with the 0.4 power of the amount of walking or bicycling respectively.” Expressed simply, more people biking leads to fewer per capita crashes while fewer people biking leads to more per capita crashes.
Jacobsen also derives a formula for how this affects the individual cyclist: “Taking into account the amount of walking and bicycling, the probability that a motorist will strike an individual person walking or bicycling declines with roughly -0.6 power of the number of persons walking or bicycling.” In other words, as more people bicycle, the per capita risk to each bicyclist of a crash decreases; if fewer people bicycle, the per capita risk to each bicyclist increases.
Helmets do not make cyclists as safer as commonly thought
For the individual, of course, the story is different. Wearing a helmet is likely safer than not wearing one. This is true for bicyclists; it is also true for people who are skydiving, rock climbing, sitting under an oak tree, or taking a bath. Individually, we make our decisions based on our own risk tolerances and values, and many of us choose to wear helmets and encourage our loved ones to do so.
But at the broader level, where we ought to analyze legislation and public policy, how much safer will a helmet make a person in a bike crash that leads to a head impact? This is a topic of debate and uncertainty, but as research methods improve we move further from some of the magical thinking that took hold due to early estimates—derived from emergency room data rather than population data—that suggested helmet effectiveness rates of 85% and above.
Generally, those estimates came from retrospective studies that looked at people with head injuries in emergency rooms and compared the numbers who lived and died, and whether they were wearing helmets when they were hit. When more recent studies have attempted to compile these data into meta-analyses with more informative sample sizes, their results do not approach the long-accepted 85% level. Some show a smaller effect; others, none at all. In fact, in population-level studies focusing on hospitalization rather than emergency room visits, helmets have no discernible, statistically significant effect on hospitalization rates. (Jacobsen 2012)
Recent studies that have focused on overall health, rather than simply crash mortality rates, have shown that the individual and public health benefits grossly outweigh the costs, by a factor of 20:1. (De Jong 2012)
The mandatory helmet law in Maryland will increase danger for Maryland cyclists
Assuming that the helmet law will decrease cycling by the 37.5% average in Maryland, the total Maryland cycling population, post helmet law, would shrink to only 62.5% of the current cycling population. Assuming also that Jacobsen’s safety-in-numbers effect holds true in Maryland—as it has consistently throughout California and across Europe—the number of motorists colliding with people bicycling will increase by roughly 17.1% per capita (1-0.6250.4=0.171)
For the individual, these assumptions mean that the likelihood of injury from a crash with a motor vehicle would increase by roughly 33% (0.625-0.6=1.326)—regardless of whether the individual wears a helmet. The increased risk comes solely because mandatory helmet laws take people off bicycles, and fewer people on bicycles makes the remaining bicyclists less safe. Substantially.
Maryland does not keep much data on bicycling, but one piece of data that we do have is that in 2010, there were 734 reported bicycle crashes in Maryland. Looking only at this data—and assuming ridership decreases by 37.5% from the helmet law in Maryland—we might expect only 459 crashes instead of 734.
However, this expectation is wrong. Due to the decreasing “safety in numbers,” we would instead expect to see 537 crashes, or 78 additional crashes directly attributable to the mandatory helmet law. So even though the total number of crashes might decrease, that is not because the law has made cyclists safer; it is because substantially fewer people are riding bikes, and those that still ride are measurably less safe, because of the law.
Discouraging cycling runs counter to Maryland’s other priorities
The state of Maryland has launched, or is poised to launch, two programs dedicated to encouraging cycling. The mandatory helmet law would undermine the success and safety of both.
First, knowing the overall benefits of biking to public health and well-being, transportation, economic development, and other public priorities, the state of Maryland initiated a campaign to get more people riding bikes. Maryland’s Department of Transportation introduces the campaign on their website with:
Governor O’Malley’s Cycle Maryland initiative is an effort to encourage more Marylanders to get out and ride, and to make bicycling a true transportation alternative. Cycling is a great way to connect to your community, support a cleaner environment, encourage a healthier lifestyle, reduce household transportation costs and enjoy Maryland’s magnificent landscape.
With the mandatory helmet law reducing ridership, Maryland will be left with more people to figure out how to move, and will have to treat more people for health problems associated with sedentary lifestyles.
Second, Maryland has contributed funds to expand the popular and successful Capital Bikeshare program to Montgomery County. Due to the nature of bikesharing, users are less likely to wear helmets, more likely to be casual rather than experienced users, and more likely to be operating in urban environments with motor vehicles. So perhaps the legislators proposing this mandatory helmet bill mean to ensure the safety of those riders, before bikesharing arrives in the state?
However, again, consider the data: Capital Bikeshare users have logged over 3.4 million trips, with an approximately 38% lower helmet usage rate than the general population. (Kraemer 2012) There have been zero fatalities and only one head injury. That is roughly one crash for every 88,000 miles ridden! Yet by driving potential cyclists away, a mandatory helmet policy would undermine the likelihood of success of the program in Montgomery County, Baltimore, and other areas statewide.
That safety record speaks for itself and shows that biking is not an inherently dangerous activity. Mandatory bicycle helmet laws falsely portray it as such, and in doing so create a false sense of danger that limits ridership and undermines the many positive impacts of mass cycling for Maryland.
“Contributory negligence” makes the law especially harmful
And finally, some believe that this law is acceptable and benevolent and will not have these impacts because there is no fine for violation. But this law has other, even more dire consequences for violators.
Maryland, like the District and Virginia, is a “contributory negligence” jurisdiction. That means if the victim of a crash contributed in any way to her own injury, she can claim no civil recovery for her damages. In Maryland, violation of a law is negligence per se.
Thus, it is possible that a cyclist who rides the bus to work on a rainy morning but chooses to take a bikeshare bike home when the weather clears, and suffers permanent brain injury when a drunk driver veers into a bike lane and strikes her, could be denied any civil recovery as a result of not wearing a helmet.
Is this the transportation future we want in Maryland? Is this the sort of public policy we hope to encourage?
In Maryland, we can anticipate a mandatory helmet law to reduce bicycle ridership by 37.5% (along with its accompanying public health, environmental, and economic benefits), per capita crashes to increase by 17%, and the per capita risk of a crash to increase by 33% for every person riding a bike in the state of Maryland, regardless of whether he or she wears a helmet.
In a broader sense, these laws are a form of victim blaming—telling bicyclists that it is our responsibility to avoid the risk of injury by padding ourselves, rather than the state’s to design a transportation network capable of moving non-motorists with a decent level of safety and efficiency.
WABA opposes a mandatory helmet law in Maryland because it is bad policy based on accepted, tested, and peer-reviewed data—not just some libertarian philosophy or desire of cyclists to “feel the wind in our hair.”
Fundamentally, we do believe that the legislators proposing this mandatory helmet law hope to do what is best for bicyclist safety, but they have significantly erred in determining what will, in fact, be best. They have the power to impose new risks on each of us who rides a bike, even when we wear helmets. We hope they will consider this information seriously and decide that a mandatory helmet law is a bad policy for the state of Maryland.
If you’d like to voice your opposition to Maryland’s House Bill 399, you can do so here.
De Jong, Piet. 2012. The Health Impact of Mandatory Bicycle Helmet Laws. Risk Analysis. 5 (32): 782-790.
Jacobsen, Peter L. 2003. Safety in Numbers: More Walkers and Bicyclists, Safer Walking and Bicycling. Injury Prevention 9 (3): 205-209.
Jacobsen, Peter L. and Harry Rutter. “Cycling Safety” City Cycling. Ed. John Pucher, Ed. Ralph Buehler. Cambridge: MIT Press, 2012. 141-156.
Kraemer, John D., Jason S. Roffenbender, and Laura Anderko. 2012. Helmet Wearing Among Users of a Public Bicycle-Sharing Program in the District of Columbia and Comparable Riders on Personal Bicycles. American Journal of Public Health 102 (8): e23-e25.
Robinson, Dorothy L. 1996. No Clear Evidence from Countries that Have Enforced the Wearing of Helmets. British Medical Journal 332 (7543): 722-725.
Photo by Richard Masoner / Cyclelicious on Flickr
Last night, we asked you to take action to oppose a mandatory helmet law introduced in the Maryland House of Delegates’ Committee on Environmental Matters. In response, some of you asked for additional information on the “debatable” effects on bicyclists’ safety and the negative impacts on cycling that a mandatory helmet law would have.
We vocally and overwhelmingly approve of helmets here at WABA. All of our staff and volunteers wear them, we require participants to wear them at all WABA events, and we teach how to wear them properly in all WABA education classes. Helmets provide an important last line of defense in the safety equation during a crash. When everything else has gone wrong, helmets have saved many bicyclists from more serious injuries or even death. We don’t get on our bikes without our helmets and we strongly encourage every cyclist out there to wear one.
However, mandatory helmet laws requiring all bicyclists to wear helmets are not effective at increasing helmet usage without significantly affecting ridership. There are many studies that show helmet usage increases when laws are passed—but critically, not without a negative effect on overall bicycle ridership. In Australia, ridership dropped 37.5 percent between 1985 and 2011 after such a law was passed. During the same time, population growth was three times higher than the growth of cycling, meaning following the passage of a mandatory helmet law, there was a net decrease in bicycling.
These laws negatively impact bicycle ridership by throwing up one more barrier (financially and behaviorally) to bike riding. Therefore, a potential bicyclist will be driven to choose another mode of transportation. Additionally, a recent New York Times article quoted Piet de Jong, a professor in the department of applied finance and actuarial studies at Macquarie University in Sydney: “Pushing helmets really kills cycling and bike-sharing in particular because it promotes a sense of danger that just isn’t justified—in fact, cycling has many health benefits.” Jong has studied the public health impacts of bicycling and has concluded that the positive health benefits outweigh risks of helmetless riding 20 to 1. In a country in the midst of an obesity epidemic, encouraging a few miles of bicycling everyday could lead to a considerable reduction in overall healthcare costs. And as jurisdictions like Montgomery County consider bikesharing programs, it’s important that those programs are accessible. Mandatory helmet laws in Maryland could potentially kill the momentum for bikesharing, as the law would promote a sense of danger for cycling, ignoring the obvious overall health benefits.
And finally, these laws are merely an easy “fix” for legislators that distract from larger safety issues—such as the lack of safe, separate and comfortable places to ride. Adults and kids need safe spaces to ride on our roads that are separate from cars. We at WABA believe there are better legislative ways to keep bicyclists safe, such as better and more targeted enforcement of current traffic laws (especially distracted driving), increased bicyclist education, and, most importantly, the construction of separated bicycling facilities.
Helmets are an important part of keeping bicyclists safe and WABA enthusiastically supports their promotion and use, but mandatory helmet laws do more harm than good.
The Maryland House of Delegates is considering removing the “under 16″ age requirement of its current mandatory helmet law in HB 339 to require all bicycle riders to wear a helmet. Please take a minute and contact the members of the Committee on Environmental Matters and ask them to oppose HB 339.
Attention Maryland voters! Please take one moment to send an email to the members of the Environmental Matters Committee of the Maryland House of Delegates opposing the passage of a mandatory helmet law for all bicyclists on every road, trail, or sidewalk in the state of Maryland.
At WABA, we encourage and teach safe and responsible cycling practices, including helmet use. But we do not believe that mandatory helmet laws are the proper approach. While their impact on safety is debatable, their impact on cycling rates (especially in jurisdictions implementing or seriously studying bikesharing) is clearly negative.
Please CLICK HERE to let the Environmental Matters Committee know that you are a responsible cyclist and a responsible adult capable of making your own decision regarding safety equipment, and that you OPPOSE HB 339 and its imposition of a mandatory helmet requirement.
Summary: Is the Swedish airbag bike helmet a reality? Can it really protect the way a traditional helmet does? We are waiting to see test results and answer a lot of questions.
These British newspaper / blog articles with an embedded video introduces Swedish headgear that is based on the airbag principle, with an inflating protective bonnet designed to deploy when the rider is about to crash.
Airbag helmets have been the subject of conversation for years, often accompanied by photos of riders with balloons on their heads. But this one appears to be a serious attempt to put the mechanism to work. The device is a project of two Swedish design students, and other sources say it is expected to be on the UK market in 2011 at a price of 260 British pounds.
The airbag is nylon, and inflates with a gas generator when embedded gyros and accelerometers tell it a crash is taking place. The gyros have to be powered during use, so the Chieftan has a rechargeable battery. That seems like a real drawback to us, since the user has to be aware of the battery charge level (there are led indicators) and remember to keep it charged. After a crash the manufacturer wants the headgear back to check its “black box” for recorded movements prior to your crash. They offer a discount on the replacement. That implies that this is not a multi-use product.
If the device can detect all crash scenarios, the mechanism could be used to deploy other forms of protection for other body parts.
The video shows a test dummy on a bicycle struck from behind by a car indicated as moving at 20 kph (12 mph). The dummy is thrown over the hood and impacts its head on the flat part of the windshield. The bag deploys prior to the impact.
That is one specific scenario. But did the helmet perform? You can see the helmet bottom out and let the head hit the windshield anyway, and there is no instrumentation registering how many g’s the dummy head saw. And what would happen in a simple fall? Collision with a tree branch or utility pole? The mirror of a bus, or the front of a truck? Another impact after the bag begins to lose air?
Helmet lab testing normally includes testing wet, cold and hot samples. They are tested against rounded anvils and curbstone anvils as well as flat ones. How well would this device perform against a grapefruit-shaped anvil, or one that was the shape of a curb?
It is not possible to answer questions based on one article and video. There is no need to be too skeptical until we see more. That same thought applies to the helmet with a fiberboard helmet liner introduced by design students in the UK last month.
Perhaps the most important immediate news is that at least somebody is trying to solve the shared bike program helmet problem. Shared bike programs all over the world are in need of an easily transportable helmet or one that can be dispensed from vending machines at very low cost for users of shared bicycle programs who did not think to bring a helmet. There is at least one folding helmet from Dahon currently available in Europe, but it does not meet US standards and is expensive. We have been talking to manufacturers about shared bike helmets recently, but getting glazed looks that tell us they are thinking “there is not enough market to make it pay.”
Stay tuned, the airbag helmet is bound to be interesting!
Courtesy of WABA’s helmet advocacy program, the Bicycle Helmet Safety Institute: BHSI.org