How Motorcycle Helmets Work

HOW MOTORCYCLE HELMETS WORK Helmets are an essential part of any motorcyclist's arsenal of safety gear How do motorcycle helmets protect your head? During a crash, a motorcyclist's head is hurled through space MPH × GRAVITY The head is subject to the force of speed plus gravitational forces, also known as G-forces Motorcycle helmets have been shown to reduce risk of head injury by 69% and risk of death by 42% 42% 69% When you crash at 65 mph, your head is subject to the force of 65 mph on a 10-pound object (your head) plus G-forces As you crash, your head goes from 65 to 0 in a short amount of time Зх Motorcycle riders who do not wear a helmet are more than 3 times as likely to sustain traumatic brain injury than riders who wear a helmet While your head stops, your brain keeps moving The resulting impact of the brain on the inside of the skull is what causes traumatic brain injuries Motorcycle helmets have 4 basic components: Motorcycle helmets work by reducing the amount of force the brain receives during a crash Outer shell Made of polycarbonate or fiber-reinforced composites Designed to compress upon impact Disperses energy away from the site of impact Protects against penetration by foreign objects Impact-absorbing liner Made of a dense layer of expanded polystyrene Cushions and absorbs the shock of impact An impact-absorbing foam liner compacts and diffuses the force of a crash impact throughout the helmet material TIME This greatly reduces the amount of force that acts on your head Helmets extend your head's stopping time by 6 milliseconds, giving your head more time to slow down and reducing both rotational forces and internal strains Other protective attributes of motorcycle helmets Comfort padding Retention system Also known as the chin strap Keeps the helmet from falling off during a crash Made of soft foam and cloth Keeps helmet tight against your head Wicks away perspiration Face shield Keeps wind and debris out of the eyes, ensuring good visibility Face protection Protects against road rash and jaw fractures Ear protection Cuts wind noise and refines hearing Any motorcycle helmet worth buying will be at least DOT (Department of Transportation) certified, meaning: Peak acceleration cannot exceed 400G Acceleration pulses over 200G cannot exceed 2 milliseconds Acceleration pulses over 150G cannot exceed 4 milliseconds This means impact forces must be neutralized quickly, to adequately prevent against head injury Robert J. DeBry FG-JET ASSOCI ATES DOT FMVSS No. 218 CERTIFIED According to the NHTSA, 67% Motorcycle helmets are 67% effective in preventing brain injuries The U.S. General Accounting Office (GAO) reports that helmeted riders have up to an 85% reduced incidence of severe, critical Information From: http:/www.smarter-usa.org/documents/MSF-Helmets.pdf http:/www.helmets.org/general.htm http:/www.nhtsa.gov/people/injury/pedbimot/motorcycle/safebike/preventing.html http:/www.hopkinsmedicine.org/news/media/releases/motorcycle_helmets_reduce_spine_injuries_after_collisions_helmet_weight_as_risk_to_neck_called_a_myth http:/www.superstreetbike.com/explaining-motorcycle-helmets-put-lid-it http:/www.smf.org/docs/articles/dot http:/motorcycleinfo.calsci.com/Articles/MotorcyclistHelmets.html 85% injuries than unhelmeted riders IMPACT