Volpe, The National Transportation Systems Center reports that nearly half of bicyclists and one quarter of pedestrians who are killed by a large truck first impact the side of the truck. During a crash with a large truck that has high ground clearance, pedestrians, bicyclists, and other vulnerable road users can fall into the space between the front and rear wheels and suffer often-fatal crushing injuries. Truck side guards are vehicle-based safety devices that physically cover that exposed space, shielding road users from being swept underneath the wheels.
Volpe’s review of side guard design and crash outcomes in countries requiring these safety devices indicates that the safety effectiveness of sideguards is well established. For example, following a mandate requiring truck side guards in the United Kingdom, studies showed that there was a 61 percent drop in cyclist fatalities and a 20 percent drop in pedestrian fatalities related to side-impact collisions with trucks.