Helmets
Response: We have never found this to be the case. Bike helmets do not affect vision. If the helmet intrudes on upward vision it will be evident to the user, who can adjust the tilt of the helmet to raise the front lip. Bike helmets also do not affect hearing, since normally they do not cover the ears. That question is easily settled by riding with and without a helmet, or by standing beside a road with helmet on and off. The US DOT has conducted a study on this question using motorcycle helmets and found that even these larger helmets with additional coverage do not affect hearing, and have little effect on vision.
Response: This is a subjective judgment for each individual, and is easily tested by the user. Most riders find today's helmets light, comfortable and cool enough.
Response: Putting a helmet on takes less time than putting on bike gloves, but it does add another step every time you get on the bike, and we agree that it can be a nuisance on very short trips from one store to another. So is fastening your seat belt in a car, but you do it for safety. The helmet can be left with the bike, locked if the bike needs to be locked in that location.
Response: We have ample evidence from medical studies that helmets are indeed highly effective, and you will find references on our statistics page. Although bicycle helmets are tested in labs in impacts at 14 miles per hour, they usually do a fine job of protecting the rider in a crash where the initial forward speed is higher, because the severity of the impact is normally determined by the closing speed of the head and pavement, not by the rider's forward motion. Research on crashed helmets shows that most people hit the ground at a relative speed of about 10 MPH. If a rider is hit by a car or hits a brick wall at 30 mph and the head takes a direct blow at that speed, no helmet will prevent injury or death. But that type of crash is rare, and helmets are designed for the severity of the most frequent crash types. As a reality check, ask any club cyclist about helmet effectiveness. They have shared experience that gives them more perspective on crashes. Club cyclists were the first to adopt helmets in the U.S., and the first to see the results. You will see helmets on all or most of the riders on virtually any club ride in the US. Among racers, the United States Cycling Federation (now USA Cycling--our road racing organization) adopted a mandatory helmet rule in 1986, because every year two or three riders were being killed in their races and more were suffering head injuries. In the years since it has been rare for a racer to die in a US race, even though their crashes occur at racing speeds. We have a page up on helmet protection limits.
Response: When the impact occurs, the helmet is between the head and the hard place, where weight is unimportant. If that were not the case, we would see an increase in head or neck injuries in helmeted riders here, and that has not happened. Motorcycle helmets are much heavier than bicycle helmets, and if there were a tendency for helmet weight to be a factor it would have shown up there. Under normal riding conditions, the weight of a helmet does not destabilize the rider. Competitors in BMX competitions with three pound motorcycle helmets on their heads maintain amazing balance on difficult track conditions and jumps.
Response: A helmet does have a larger diameter than the head. But it would be more accurate to say that the helmet might increase the likelihood of hitting the helmet itself, not the head.
Response: There is no consensus among the medical community on the threshold of rotational injury or how to measure it, although there is probably a rotational component in most serious head injuries. The standards-making community believes that a helmet that protects well against straight through (translational) impacts also reduces the effects of rotational injury, since rotational motion comes from off-center translational impacts. But the damage to the interior of the brain is not simply a function of a turning motion. It results from different parts of the brain moving in different directions at different speeds after even a translational impact. Reducing the severity of the impact reduces that type of damage. There is potential for improvement of current helmets eventually when rotational injury is better understood and means of predicting it in a crash are developed and accepted. Because this is an area requiring further research it has always been an easy target for raising doubt about the performance of current helmets. But in fact current helmets are a long way from perfect in almost any respect, and this is just one element that can be improved. That does not negate the benefits of wearing today's helmets. They work very well despite their imperfections!
Response: Although polycarbonate is used in many helmet shells and is suspected as one of the sources of the chemical BPA in the environment, there is no evidence yet that the helmet shells pose any danger to the wearer. We are more concerned about materials used in the interior of the helmet in contact with the skin. See our page on plastics in helmets for more info.
Response: Like any piece of wearing apparel, you have a choice of cheap or expensive. In the US market, cheap helmets are less than $10 (everyday prices at Wal-Mart and Target start at $7.14), and are just as protective as the more expensive ones. A study in New Zealand suggested that helmets there were not cost-effective, but in the US the analysis prepared by the National Public Interest Research Institute in 1994 suggested that every dollar spent on bicycle helmets saves $25 to $32. Since that time the cost of the average bicycle helmet here has fallen and health care costs have risen steeply.
Response: We have not observed that phenomenon. Riders here were just as careless in the 1960's and earlier without helmets as they are today. We have never been able to identify a case where a rider we knew began wearing a helmet and changed their risk-taking. The individual's perception of injury risk in a bicycle crash is generally not centered on their head, but on body parts. Most riders do not consider the head the most vulnerable part of the body. They are primarily concerned with the road rash and broken bones that are much more frequent than brain injuries. Helmets do not change those risks. Helmets protect only the head. Many motorcycle riders here who reject helmets still use leather clothing for skid protection. Once accustomed to a helmet, riding without it does make the rider feel vulnerable - - for the first half mile. Similar effects can be seen with seat belts, where the risk compensation argument also was used at one time, and even anti-lock brakes have been accused of making car drivers more aggressive.
Response: Actually, some do, and increasingly parents are helmeting their children there, as evidenced by this report on helmet promotion by their Foundation for Consumer Safety. But the cycling tradition is so ingrained in Holland that most adults do not see any need for helmets, despite the injuries documented by the Foundation report. They benefit from uniquely safe bicycle facilities and drivers who are expecting them on the roads because they are so numerous and who give them full right of way when appropriate. When compared to the US, there are significant differences in road design, road surfaces, trails, traffic, signalization, motorists' attitudes, cyclists' attitudes, legal consequences of a car/bike crash, the bicycles themselves, car lighting, bike lighting and accessories, climate, the type of riding people do, the normal uses they put bicycle to, the number of cyclists on the roads and a whole range of other factors. We would not tell the Dutch they need helmets, although we wear one when cycling there. But we would tell a US rider that we think you need one here. (For a view of what we need to be doing in the US to improve our road environment, check out this campaign, one that we have supported and have attempted to advance without any success.)
Response: Many attempts we have seen in the U.S. to measure helmet effectiveness or helmet use nationally based on general statistics of bicycles on the road or rider surveys are indeed not useful. Anyone who has worked with bike riders in this country would not ask the question "How much did you ride last year/quarter/month" and expect a valid answer. Exposure data calculated from such surveys, including the survey by CPSC, are not in our opinion valid. The New York Times published an article in 2001 written by a reporter who missed that point, and reached some startling -- and invalid -- conclusions. We have a page up on that article. But we do consider valid a number of clinically-based studies in the U.S. on helmet effectiveness. We have parts of several of them included in our statistics page, including the landmark study by Thompson, Rivera and Thompson done at Harborview Injury Prevention Center and published in the New England Journal of Medicine in 1989. The same team completed another study that adds helmet analysis to the clinical data. You can find it on the Snell Foundation Web site. The study is old, but helmets sold in the US have actually improved since the data was collected, so we regard the conclusions as still valid and probably conservative. More importantly, the protective effect of helmets has been demonstrated in the field so thoroughly over a period of decades that statistical analysis based on poorly gathered data adds nothing to the knowledge base.
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