Whitewater Helmet STAR: Evaluation of the Biomechanical Performance and Risk of Head Injury for Whitewater Helmets.

More than six million people participate in whitewater kayaking and rafting in the United States each year. Unfortunately, with these six million whitewater participants come 50 deaths annually, making it one of the highest fatality rates of all sports. As the popularity in whitewater activities grows, the number of injuries, including concussions, also increases. The objective of this study was to create a new rating system for whitewater helmets by evaluating the biomechanical performance and risk of head injury of whitewater helmets using the Summation of Tests for the Analysis of Risk (STAR) system. All watersport helmets that passed the EN: 1385: 2012 standard and that were clearly marketed for whitewater use were selected for this study. Two samples of each helmet model were tested on a custom pendulum impactor under conditions known to be associated with the highest risk of head injury and death. A 50th percentile male NOCSAE headform instrumented with three linear accelerometers and a triaxial angular rate sensor coupled with a Hybrid III 50th percentile neck were used for data collection. A total of 126 tests were performed using six different configurations. These included impacts to the front, side, and rear using two speeds of 3.1 and 4.9 m/s that modeled whitewater river flow rates. Each helmet's STAR score was calculated using the combination of exposure and injury risk that was determined from the linear and rotational head accelerations. The resulting head impact accelerations predicted a very high risk of concussion for all impact locations at the 4.9 m/s speed. The STAR score varied between helmets indicating that some helmets provide better protection than others. Overall, these results show a clear need for improvement in whitewater helmets, and the methodologies developed in this research project should provide manufacturers a design tool for improving these products.

Proposed Injury Threshold for Drone Blade Lacerations.

Drones have been increasing in popularity and are able to cause skin injuries ranging from minor abrasions to severe lacerations. The objective of this study was to determine the aspects of drone blades that cause injuries, and to help manufacturers design safer drones by suggesting an injury threshold. The blade tip thickness, blade length, angular velocity, and blade tip speed of a variety of popular drones were measured. The injury caused by each drone blade contacting a fetal bovine skin surrogate at different speeds was recorded. Blade tip speed had the highest correlation to injury severity, while blade tip thickness, blade length, and rpm had little to no correlation with the resulting injury. Blade tip speeds above 25 m/s resulted in minor abrasions, and speeds above 60 m/s resulted in minor lacerations. To prevent severe injuries, drone manufacturers should design drones with blade tip speeds below the threshold of 60 m/s.