Geofencing to prevent collisions in drivers’ interactions with emergency vehicles

• Geofence-based in-car warnings were assessed in two driving simulator experiments. • Geofencing can increase safety in high-risk situations. • Geofencing can decrease delays for emergency vehicles. • Nearly half of drivers without a warning failed to yield in the intersection. • Drivers adhered to the warnings and avoided collision. The interaction between emergency vehicle drivers and surrounding road users is associated with risks. This study explored the application of geofencing to improve interactions between drivers and emergency vehicles to reduce the risk of collisions in high-risk scenarios. Two high-risk scenarios, an off-ramp collision, and an intersection scenario, were used in two driving simulator experiments with 64 participants in total. Half of the drivers received a geofence-based warning about the upcoming traffic situation. The results indicate that geofencing, when applied to provide warnings in specific locations, improves driver behavior. In the off-ramp experiment, all drivers who received a warning avoided the off-ramp and thereby avoided the collision site, whereas all other drivers took the off-ramp. In the intersection experiment, the warning led to earlier deceleration, allowing the emergency vehicle to pass safely and with minimal delay; whereas nearly half of those who did not get a warning failed to yield to the emergency vehicle. The drivers acted based on the warning they received, even when they had not yet seen the emergency vehicle. The findings suggest that geofencing can improve driver behavior by detecting emergency vehicles early and reliably, thereby improving traffic safety and minimizing delay for emergency vehicles on call.