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Popular but precarious: low helmet use among shared micromobility program riders in San Francisco
Willow Frye1,2, Lara Chehab1,2, Joshua Feler1
1Department of Surgery, University of California, San Francisco, San Francisco, CA, United States.
Background:
Shared micromobility programs (SMPs) are integral to urban transport in US cities, providing sustainable transit options. Increased use has raised safety concerns, notably about helmet usage among e-scooter and e-bicycle riders. Prior studies have shown that head and upper extremity injuries have risen with SMP adoption, yet data on helmet use remains sparse.
Methods:
This cross-sectional observational study evaluated helmet use among 5,365 riders (e-bicycles, conventional bicycles, and e-scooters) in San Francisco during February and March 2019. Observations were made at seven key intersections during peak commute hours on clear days.
Results:
The majority rode conventional bicycles (77.1%), followed by e-bicycles (19.0%) and e-scooters (3.9%). Most vehicles (82.2%) were personally owned, with the remainder shared via SMPs. Helmet usage was substantially lower among SMP riders, with shared e-scooter users showing the lowest compliance. Specifically, shared e-scooter riders wore helmets 70% less frequently than personal e-scooter riders and 59% less than shared e-bike riders. Dockless e-bike riders used helmets 42% less than those on docked e-bikes.
Conclusion:
This study exposes significant gaps in helmet usage among SMP riders, highlighting a pressing need for public health interventions and policy adjustments to improve safety and reduce head injury risks. The findings suggest that helmet use is notably deficient among e-scooter and dockless e-bicycle riders, underscoring the urgent need for targeted safety regulations as cities continue to integrate SMPs into their transportation frameworks.
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