The Assessment of the Pedestrian Safety in Conflict With Cars and Motorcycles at Non-signalized Intersections Using TTC and PET

Pedestrians are subjected to high levels of risk at non-signalized intersections. Pedestrians at these intersections have conflicts with different types of vehicles such as motorcycles and cars. In this paper, pedestrian safety is compared between those two groups of vehicles using Time to Collision (TTC) as well as the Post Encroachment Time (PET). Data were collected from an intersection called Vesal-Bozorgmehr in Tehran. The one-way ANOVA was used to compare those two groups. The number of observations for each TTC and PET being the dependent variable was 758 and 791 respectively. Analyses indicated that LogTTC in conflicts between vehicles and pedestrians is 0.03 units more than conflicts between motorcycles and pedestrians and LogPET in conflicts between vehicles and pedestrians is 0.09 units lower than conflicts between motorcycles and pedestrians. TTC is used for identification of situations being potentially dangerous for pedestrians and PET is used for identification of critical situations for pedestrians. As TTC for the conflicts between pedestrians and vehicles is lower than that of for pedestrians and vehicles, motorcycles potentially cause more dangerous situations for pedestrians whereas when it comes to PET, vehicles have lower PET than motorcycles, so vehicles are more able to make critical situations for pedestrians.