Helmet Safety |
HomeCyclingWalkingResourcesSafetyEvents | A good bicycle helmet must be able to absorb impact energy just as motorcycle helmets do to prevent brain injury. To work properly a bicycle helmet must fit properly and be cared for properly: The helmet should sit level on the head, covering the forehead in front. The chin strap splitter should lie right under the ears. All straps should lie flat, not be twisted The chin straps should be tight enough to allow only one finger between the strap and neck -- without choking. The helmet should not rock from side to side. The helmet should rock slightly forwards and backwards. If it can lift up off the forehead or come down over the eyebrows it needs further adjustment. Trim loose ends of overlapping straps. Add-on stickers and paint are cute but can affect the strength of the shell and may void the warranty. Most of the best helmets have three elements: a shell, a liner and straps and buckle. Shell: A full-cover hard shell spreads the impact energy in a collision with a sharp or pointed object. The shell can have some vents and still be strong enough. Fiberglass, Lexan and ABS plastic are all good shell materials. The shell should not have any sharp snag points. Helmets which pass the recognized impact tests are available with soft shells and no shells. Soft shell helmets are almost as light as no shell helmets and more durable. No shell helmets are generally the lightest weight. Most come with a nylon cover. It is necessary to keep this cover on for the helmet to work properly. Liner: A good helmet must have a stiff polystyrene (Styrofoam) or related liner. This is a non-springy foam that absorbs shock and doesn't bounce back at your head. All top rated bicycle helmets use expanded polystyrene (EPS) -- a slightly harder version of the familiar white ice-chest foam and the packing material used to protect stereo equipment during shipping. Spongy foam can be added for comfort, but it absorbs very little shock in a life-threatening crash. The stiffer polystyrene must be included in the construction to absorb the energy of a blunt impact. Note: The density and thickness of the liner are critical factor in the amount of energy it will be able to absorb. Strap & Buckle: The helmet must stay on your head even if you hit hard surfaces more than once--a car, perhaps, and then a curb. The helmet needs a strong strap and fastener.
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