Driver’s gaze behavior when approached by an emergency vehicle – The effects of in-car warnings and system introduction

• EVA warnings promote earlier scanning of mirrors. • Eye gaze behavior changed from first to second emergency vehicle interaction. • A false expectation of EVA warnings correlates with looking forward less. • The driving simulator data did not reveal any differences in driving behaviors. This study investigates drivers’ eye gaze behavior in response to Emergency Vehicle Approaching (EVA) warnings. EVA warnings, delivered through in-car alerts, provide advance notice of approaching EVs, enabling drivers to move over in time. Previous research indicates that EVA warnings influence driver behavior positively, promoting safer interactions. This study expands further by exploring the role of system introduction to make drivers benefit from EVA warnings. A simulator experiment with 73 participants was conducted. Before driving, half of the participants were introduced to the EVA system. The participants were driving on a highway and were overtaken by EVs twice during a 20-minute drive. During the drive, half of participants received EVA warnings. Gaze distribution was analyzed in three areas of interest (Forward, Mirrors, Dashboards). Analysis of driving simulator data did not reveal any differences in driving behaviors. However, the analysis of drivers’ gaze distribution suggests that EVA warnings contribute to increased mirror usage, indicating early scanning for approaching EVs. Furthermore, drivers who were introduced to the EVA system before driving but never received an EVA warning in the simulator looked through the front windshield less than drivers who were introduced and received an EVA warning. This study contributes to understanding the driver gaze behavior when receiving an in-car warning for emergency vehicles and supports previous findings regarding EVA warnings positive impact of driver behavior.