Effects of driver direct visibility in passenger vehicles on the risk of turning crashes with pedestrians

Hu, Wen / Cicchino, Jessica B.
Insurance Institute for Highway Safety
November 2025

Abstract
Introduction: This study examined if characteristics of direct visibility metrics in passenger vehicles, such as large blind zones, corresponded with being overrepresented in left- and right-turning crashes with pedestrians. It also evaluated the effects of vehicle front structures on some direct visibility metrics.
Method: The analysis included single-passenger vehicle, single-pedestrian crashes in seven states. Direct visibility metrics used in the crash analysis included driver- and passenger-side blind zone sizes, front nearest visible point (NVP) distance, and front field of view (FOV) width. The blind zone sizes and front NVP distances were measured by using a camera-based method, which captured obscuration produced by all vehicle front structures. The front FOV width was measured at a driver’s eye-height horizon by using a laser measuring tool. Direct visibility measurements were taken on 168 unique combinations of vehicle make, series, and redesign years. Logistic regression analyses were performed to evaluate the effects of visibility metrics and other factors on the odds of a left- or right-turning pedestrian crash relative to a straight-moving pedestrian crash. Additionally, linear regression analyses were performed to examine the effects of front-structure geometries on blind zone sizes and front NVP distances.
Results: For left-turning pedestrian crashes relative to straight-moving pedestrian crashes, when compared with a small driver-side blind-zone size (<= 20%), a large (> 30%) and a medium (> 20% and <= 30%) size were respectively associated with a significant 69.7% and 59.0% increase in the odds. A small (<= 85 degrees) and a medium (> 85 degrees and <= 90 degrees) front FOV width were associated with significant increases of 50.8% and 18.2% in the odds, respectively, compared with a large front FOV width (> 90 degrees). A long front NVP distance (> 9 m) was associated with a significant 36.8% increase in the odds, and a medium distance (> 6 and <= 9 m) was associated with a nonsignificant 9.8% increase in the odds, compared with a short distance (<= 6 m). No significant effects of direct visibility metrics were found on the risk of right-turning pedestrian crashes.
Conclusions: Larger driver-side blind zones, longer front NVP distances, and narrower front FOVs were associated with increased risk of left-turning pedestrian crashes. The study also validated the effects of vehicle front structures including A-pillars, side mirrors, hoods, and windshields on blind zone sizes and front NVP distances. Practical applications: Findings could help automakers improve safety for road users outside vehicles with changes in vehicle design to enhance drivers’ direct vision and improvements to automatic-emergency-breaking technology to address vehicle-turning conflicts.
Abstract Introduction: This study examined if characteristics of direct visibility metrics in passenger vehicles, such as large blind zones, corresponded with being overrepresented in left- and right-turning crashes with pedestrians. It also evaluated the effects of vehicle front structures on some direct visibility metrics.
Method: The analysis included single-passenger vehicle, single-pedestrian crashes in seven states. Direct visibility metrics used in the crash analysis included driver- and passenger-side blind zone sizes, front nearest visible point (NVP) distance, and front field of view (FOV) width. The blind zone sizes and front NVP distances were measured by using a camera-based method, which captured obscuration produced by all vehicle front structures. The front FOV width was measured at a driver’s eye-height horizon by using a laser measuring tool. Direct visibility measurements were taken on 168 unique combinations of vehicle make, series, and redesign years. Logistic regression analyses were performed to evaluate the effects of visibility metrics and other factors on the odds of a left- or right-turning pedestrian crash relative to a straight-moving pedestrian crash. Additionally, linear regression analyses were performed to examine the effects of front-structure geometries on blind zone sizes and front NVP distances.
Results: For left-turning pedestrian crashes relative to straight-moving pedestrian crashes, when compared with a small driver-side blind-zone size (<= 20%), a large (> 30%) and a medium (> 20% and <= 30%) size were respectively associated with a significant 69.7% and 59.0% increase in the odds. A small (<= 85 degrees) and a medium (> 85 degrees and <= 90 degrees) front FOV width were associated with significant increases of 50.8% and 18.2% in the odds, respectively, compared with a large front FOV width (> 90 degrees). A long front NVP distance (> 9 m) was associated with a significant 36.8% increase in the odds, and a medium distance (> 6 and <= 9 m) was associated with a nonsignificant 9.8% increase in the odds, compared with a short distance (<= 6 m). No significant effects of direct visibility metrics were found on the risk of right-turning pedestrian crashes.
Conclusions: Larger driver-side blind zones, longer front NVP distances, and narrower front FOVs were associated with increased risk of left-turning pedestrian crashes. The study also validated the effects of vehicle front structures including A-pillars, side mirrors, hoods, and windshields on blind zone sizes and front NVP distances. Practical applications: Findings could help automakers improve safety for road users outside vehicles with changes in vehicle design to enhance drivers’ direct vision and improvements to automatic-emergency-breaking technology to address vehicle-turning conflicts.