Wearing a helmet while riding a bike significantly reduces the risk of head injury. Helmets are required by law in some states and Canadian provinces.
The most serious bicycling injuries may be prevented by the use of proper head protection. Most helmets have an interior lining of crushable foam, designed to absorb the force of an impact, and a thin outer shell of high-impact plastic, usually perforated for ventilation.
Most good bicycle helmets meet impact standards set by the American National Standards Institute (ANSI), the Snell Memorial Foundation, or the Consumer Product Safety Commission (CPSC). The CPSC standard was mandated by United States law in 1999. By the mid-1990s many states of the United States had passed laws requiring minors to wear bicycle helmets while cycling.
|