title: The impact response of traditional and BMX-style bicycle helmets at different impact severities.
abstract: Bicycle helmets reduce the frequency and severity of severe to fatal head and brain injuries in bicycle crashes. Our goal here was to measure the impact attenuation performance of common bicycle helmets over a range of impact speeds. We performed 127 drop tests using 13 different bicycle helmet models (6 traditional style helmets and 7 BMX-style helmets) at impact speeds ranging from 1 to 10m/s onto a flat anvil. Helmets were struck on their left front and/or right front areas, a common impact location that was at or just below the test line of most bicycle helmet standards. All but one of the 10 certified helmet models remained below the 300g level at an impact speed of 6m/s, whereas none of the 3 uncertified helmets met this criterion. We found that the helmets with expanded polystyrene liners performed similarly and universally well. The single certified helmet with a polyurethane liner performed below the level expected by the Consumer Product Safety Commission (CPSC) standard at our impact location and the helmet structure failed during one of two supplemental tests of this helmet above the test line. Overall, we found that increased liner thickness generally reduced peak headform acceleration, particularly at higher impact speeds.
authors.affiliation: MEA Forensic Engineers & Scientists, 11-11151 Horseshoe Way, Richmond, BC V7A 4S5, Canada.
authors.forename: Alyssa L
authors.initials: AL
authors.lastname: DeMarco
authors.affiliation: MEA Forensic Engineers & Scientists, 11-11151 Horseshoe Way, Richmond, BC V7A 4S5, Canada.
authors.forename: Dennis D
authors.initials: DD
authors.lastname: Chimich
authors.affiliation: MEA Forensic Engineers & Scientists, 23281 Vista Grande Dr., Suite A, Laguna Hills, CA 92653, USA.
authors.forename: John C
authors.initials: JC
authors.lastname: Gardiner
authors.affiliation: MEA Forensic Engineers & Scientists, 11-11151 Horseshoe Way, Richmond, BC V7A 4S5, Canada; School of Kinesiology, University of British Columbia, 210-6081 University Blvd., Vancouver, BC V6T 1Z1, Canada. Electronic address: gunter.siegmund@meaforensic.com.
authors.forename: Gunter P
authors.initials: GP
authors.lastname: Siegmund
mesh_terms: D000054:Acceleration; D001642:Bicycling / Q000293:injuries*; D001930:Brain Injuries / Q000517:prevention & control*; D003257:Consumer Product Safety; D004867:Equipment Design; D006260:Head Protective Devices / Q000592:standards*; D006801:Humans
keywords: Acceleration; Bicycle; Foam absorber; Helmet; Impact attenuation; Skateboard