The Effectiveness of Bicycle Helmets

The Honorable Shirley Bond, Minister of Public Safety

January 11, 2012

Dear Mrs. Bond,

RE: The Effectiveness of Bicycle Helmets

I am writing to you to inform you about bicycle helmets in British Columbia.

I have noticed a disturbing trend among those who support mandatory helmet use. Without consulting factual information, they make comments about how people on bikes should wear helmets. [1]

I must first confess that helmets do save lives, and they may prevent serious head injuries in some cases. But few people actually know what bicycle helmets protect the head from.

Many people believe that bicycle helmets protect the head from injuries in the event of a crash with an automobile. This is incorrect. Bicycle helmets are designed, and only effective at protecting the head in non-life threatening impacts in solo impacts below 20km/h [2] [4]. This excludes getting hit by a car.

The way helmets are tested is even more interesting. Helmets are only tested for impact on the crown of the head; they are not even tested for impact on any of the sides. The tests in the laboratory are nothing more than a simulation of a pedestrian falling and hitting their head on the sidewalk [2]. Numerous studies have shown that bicycle helmets provide very limited protection against linear accelerations. For side impacts at 19.4 km/h or more, half the helmets had peak linear accelerations in excess of 200 g, corresponding  to severe, critical or unsurvivable head injuries [4].

When an 3000 pound automobile hits a person at 50 km/h, helmets can’t really help that much.  In fact, for some crashes,  helmets may even make some injuries worse by converting direct (linear) forces to rotational ones [3].

We all know that the most dangerous aspect of riding a bicycle is being hit by an automobile. Yet, bicycle helmets do not protect the head from that type of impact. People riding their bikes for Sunday leisure rides on the Seawall are unlikely to get into a crash, but are still forced to wear a helmet.

Riding a bicycle is an extremely safe activity; the risk of death is one in 92325, lower than swimming [5]. People riding bicycles have a less chance of head injury than pedestrians [2]. Can you explain to me why you and your government have decided to mandate helmet use, when studies have shown that they are practically useless in the event of a collision with an automobile.

Sincerely,
Kyle Zheng

References:
1) Do as I say Not as I do- http://helmetfreedom.org/1372/do-as-i-say-not-as-i-do/
2) TED Copenhagen-Why we shouldn’t bike with a helmet- http://video.tedxcopenhagen.dk/video/911034/mikael-colville-andersen
3) Cycle Helmets and Rotational Injuries- http://cyclehelmets.org/1039.html
4) Assessment of current bicycle helmets for the potential to cause rotational injury- http://cyclehelmets.org/1182.html
5) Risk of Dying in Sporting activities- http://www.medicine.ox.ac.uk/bandolier/booth/Risk/sports.html

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