Property Damage Only (PDO) collision count trends in California counties

Property Damage Only (PDO) collisions refer to any collision in which none of the involved parties were injured. In California there is a great deal of variability how PDO collisions are collected and reported by local police departments. Unlike injury involved collisions, it is not required to report PDO collisions to the Statewide Integrated Traffic Records System (SWITRS). Therefore individual police departments set their own standards on how to collect, manage and report PDO collisions. Due to this variability, most research and analyses typically exclude PDO collisions. It would not make sense to conduct a statewide study of all collisions […]

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Highway Safety Manual network screening

The Highway Safety Manual was developed by American Association of State Highway and Transportation Officials (AASHTO). It provides guidance and tools to conduct quantitative safety analyses alongside other transportation performance measures. Before the Highway Safety Manual engineers were limited in their ability to quantify safety impacts of project decisions due to a lack of an authoritative source and thus safety considerations were typically minimized in the decision making process. The Highway Safety Manual changed that and brought safety to the forefront of any operation decisions or transportation facility design. The manual is broken into four different sections: Part A – Introduction, Human Factors, and Fundamentals […]

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