Some countries and lower jurisdictions have passed laws which make riding without a helmet

Bicycle helmet

A bicycle helmet is a helmet intended to be worn while riding a bicycle. They are designed to attenuate impacts to the skull of a cyclist in falls while minimizing side effects such as interference with peripheral vision...

 illegal. The scope and details of such laws vary

Bicycle helmet laws by country

The wearing of bicycle helmets, and attitudes towards their use vary around the world. Compulsory use of helmets has often been proposed and is the subject of much dispute , based largely on consdierations of overall public health. Only two countries currently require and enforce universal use of...

.

Introduction

Modern varieties of bicycle helmet first became commercially successful from 1975. Industry helmet standards were developed from the 1970s and are still under development. Even before then, there had been calls for riders to wear helmets, based on the assumptions of high risk to cyclists and effectiveness of helmets in preventing serious injury.

The Royal Australasian College of Surgeons

Royal Australasian College of Surgeons

The Royal Australasian College of Surgeons is the body responsible for training and examining surgeons in Australia and New Zealand. The head office of the College is in Melbourne, Australia....

 played a leading role in gaining public awareness, acceptance and demand, and helmets first became compulsory across Australia from 1991 to 1992. In New Zealand, Rebecca Oaten was a prominent champion; after a disastrous head injury to her son in 1986 she travelled the country promoting the use of cycle helmets. For six years she visited an average of four schools a day, "lambasting

Appeal to emotion

Appeal to emotion is a potential fallacy which uses the manipulation of the recipient's emotions, rather than valid logic, to win an argument. The appeal to emotion fallacy uses emotions as the basis of an argument's position without factual evidence that logically supports the major ideas endorsed...

" kids with reasons why they should wear helmets A report from the Australian Department of Transport in 1987 cast doubt on the effectiveness of helmets in real accidents.

By 1991, after widespread well-resourced campaigns, the use of helmets had attained near-universal support in the United States, becoming what the League of American Wheelmen

League of American Bicyclists

The League of American Bicyclists is a non-profit membership organization which promotes cycling for fun, fitness and transportation through advocacy and education....

 characterized as a “Mom and apple pie” issue. A wide variety of official and professional bodies in the English-speaking world now support compulsory use of helmets. A 2009 poll of U.S. adults found that 86% supported helmet laws for children. Support has spread elsewhere; Safe Kids Worldwide

Safe Kids USA

Safe Kids USA is the United States' arm of the global network of Safe Kids Worldwide organizations, based in Washington DC. Safe Kids USA has over 300 chapters and coalitions in all 50 states, Washington, D.C...

, which has received financial support from equipment suppliers including a leading helmet manufacturer, was founded in 1987 and is currently active in a total of 17 countries. Australia, Canada, the Czech Republic, Finland, Iceland, New Zealand, Sweden, and the United States have bicycle helmet laws, in at least one jurisdiction, for either minors only, or for all riders. Spain requires helmets though not in cities, on especially hot days, or for riders with a medical exemption.

Helmet laws are not universal even in the United States; most U.S. states and municipalities have no laws or regulations regarding helmet use. In the U.S. 21 states and the District of Columbia have statewide mandatory helmet laws for children. 29 US states have no statewide law, and 13 of these states have no such laws in any lower-level jurisdiction either.

Support for laws

The mandatory wearing of helmets is frequently supported by medical organizations and bodies responsible for road safety.

Opposition to laws

Bicycling organizations generally oppose laws mandating the wearing of helmets.

Repeal

Israel's helmet law was never enforced or obeyed. A long and sophisticated volunteer campaign led to the revocation of the adult element, in order to allow bike-hiring schemes to work. An official predicted that this would have disastrous health consequences. Mexico City has repealed its helmet law to allow a bike-sharing scheme to work.

The wider debate on bicycle helmets

There is no consensus on whether helmets themselves are effective, useful, or worth either promotion or compulsion. Cycling in the Netherlands

Cycling in the Netherlands

Cycling in the Netherlands is a common and popular method of both transport and also recreation. The country is well equipped with cycle-paths and other segregated cycle facilities. The network reaches all parts of the nation and into the bordering nations of Belgium and Germany...

 and in Denmark

Cycling in Copenhagen

Cycling in Copenhagen is - as with most bicycling in Denmark - an important means of transportation and a dominating feature of the cityscape, often noticed by visitors. The city offers a variety of favorable cycling conditions — dense urban proximities, short distances and flat terrain...

 is perceived as a "normal" activity

Cycle chic

Today Cycle chic or bicycle chic refers to cycling in fashionable everyday clothes. The phrase Cycle Chic was coined by Mikael Colville-Andersen in Copenhagen, Denmark in 2007 as the name of a fashion blog featuring cyclists - Copenhagen Cycle Chic. The fashion concept developed in popular...

 requiring no special clothing or equipment. Official organizations have supported the use of helmets without calling for laws; the Dutch Institute for Road Safety Research (SWOV) finds contradictory evidence but on balance concludes "that a bicycle helmet is an effective means of protecting cyclists against head and brain injury". Some Dutch cycling experts and planners have opposed the use of helmets, claiming that helmets discourage cycling by making it less convenient, less comfortable, and less fashionable. They also mention the possibility that helmets would "make cycling more dangerous by giving cyclists a false sense of safety and thus encouraging riskier riding behavior."

Arguments for and against helmet laws

The debate on helmet laws has been described as "sour and tetchy".

Effects of head injury

Head injury can result in death or disastrous long-term physical and mental disability. Such injuries have happened to cyclists, and such cases have given powerful stimulus to political activity. In an opinion piece on the website of the Bicycle Helmet Research Foundation a helmet testing specialist states that some of these accidents can generate energy levels beyond those used when certifying competition motor racing helmets. One study which examined post-mortem examinations of the twenty cyclist fatalities in Auckland, New Zealand between 1974 and 1984 found that sixteen died of fatal injury to multiple organ systems, including fourteen with fatal brain injuries; four died solely of brain trauma.

Total numbers of injured cyclists

A motoring breakdown organization has sponsored an initiative by the Bicycle Helmet Initiative Trust which supports legislation, reporting that "in 2009/10 nearly 6,000 young cyclists were admitted to hospitals and of these 40% had suffered head injuries. Around 83% of young cyclists suffering head injuries were not involved in a collision with another vehicle but merely hit their head after falling from the cycle. It is, therefore, clear that cycle helmets could not only save life and limb but could prevent a huge drain on our hospital resources." In North Carolina, where bicycle helmets are compulsory for children, the North Carolina Department of Transportation

North Carolina Department of Transportation

The North Carolina Department of Transportation is responsible for building, repairing, and operating highways, bridges, and other modes of transportation, including ferries in the U.S. state of North Carolina.-History:...

 publish a fact sheet stating that a bicyclist is killed or injured approximately every six hours and that helmets reduce the risk of head injury by as much as 85% and the risk of brain injury by as much as 88%. The National Highway Traffic Safety Administration

National Highway Traffic Safety Administration

The National Highway Traffic Safety Administration is an agency of the Executive Branch of the U.S. government, part of the Department of Transportation...

 reports that in 2006, 773 bicyclists were killed in the US. In a speech arguing for helmet legislation in the UK Parliament, an MP said: "In a three-year period from 2003, 17,786 children aged 14 and under were admitted to NHS hospitals in England because of injuries incurred while cycling"

Risks relative to exposure

In the UK, some 8,000 years of average cycling will produce one clinically severe head injury, and 22,000 years one death.

Risks relative to other groups

Ordinary cycling in the UK is not demonstrably more dangerous than walking or driving, and is far safer for other road users.

Case-control studies

Cases of head injury report a lower rate of helmet-wearing than controls who have injured other parts of the body. This has been taken as strong evidence that cycle helmets are beneficial in a crash. The most widely quoted case-control study, by Thompson, Rivara, and Thompson, reported an 85% reduction in the risk of head injury by using a helmet. There are many criticisms of this study.

Effects on head injuries or deaths among cyclists

There is an active debate, with no scientific consensus; the two leading reviews have come to opposite conclusions. Robinson's review of cyclists and control groups in jurisdictions where helmet use increased by 40 % or more following compulsion concluded that "enforced helmet laws discourage cycling but produce no obvious response in percentage of head injuries". This study has been the subject of vigorous debate. A more recent review, by Macpherson and Spinks, includes two primary papers (neither of which meet the criteria for inclusion in Robinson's review) and concludes that "Bicycle helmet legislation appears to be effective in increasing helmet use and decreasing head injury rates in the populations for which it is implemented. However, there are very few high-quality evaluative studies that measure these outcomes, and none that reported data on an (sic) possible declines in bicycle use." The methods used by Macpherson and Spinks have been severely criticized.

The most studied laws are in New Zealand

Bicycle helmets in New Zealand

Bicycle helmets are mandatory in New Zealand, the only country with a helmet law enforced nationwide, requiring bicycle riders of all ages to wear helmets...

 and Australia

Australia

Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

. A study conducted by the University of New South Wales in 2011 concluded that Mandatory Helmet Laws led to a 29% reduction in cycling related head injuries. A 2011 study commissioned by the Queensland Government found Helmet wearing was associated with a 69% reduction in the likelihood of head or brain injury and a 74% reduction in the likelihood of severe brain injury. It also found little evidence to support the claim that mandatory helmet usage discouraged bike riding.

Assuming a high level of benefit from the New Zealand law, the costs still outweighed the benefits. A full analysis of the New Zealand law showed no reduction in head injuries.

Effects on the amount of cycling

Regular moderate cycling is extremely beneficial for health. An analysis of Australian census data before and after the introduction of helmet laws in some states, showed that in states which had helmet laws, the amount of cycling to work had reduced by about one third. Other evidence strongly suggests that promotion or compulsion of helmet use deters cycling. It has been suggested that this is irrelevant to health as "any cyclist who wants to exercise but hates helmets enough to quit cycling if a law is passed can turn to a multitude of other activities to stay active". However, relatively few people who bicycle as part of their daily routine, would increase gym visits or take up other exercise activities if, as a result of a mandatory bicycle helmet law, they were discouraged from cycling. For many people, exercise is only sustainable if it is integrated into daily routine such as shopping errands or traveling to and from work. Helmet laws seem to offer net health benefit only in dangerous bicycling environments under optimistic assumptions of the efficacy of helmets.

Effects on the rate of helmet wearing

Large increases in the rate of helmet wearing are usual after helmet laws. Not all laws have increased helmet use, no such increase was noted among the children covered by the North Carolina bicycle helmet law. In another area, an early rise in helmet use was followed by a fall to below pre-law levels. Attitudes to cycling, and the amount of enforcement effort, may both be relevant.