Using Basic Collision Data to Manage Road Safety

In order to be applied, state of the art network screening methodologies require advanced statistical modeling techniques, and reliable traffic volume estimates and collision data for a period typically of at least three years. For those road agencies which lack the resources to apply these more advance techniques, this paper outlines a step-by-step analysis methodology which may be used to manage road safety using only historical collision data and tools no more advanced than a spreadsheet. The methodology is not new but this paper is the first to describe the analysis within a multi-disciplinary framework. By following this methodology, agencies will be able to take a more proactive approach to road safety management. This paper works through the methodology by providing a simplified process for selecting emphasis areas for a jurisdiction as part of a safety management system. A further breakdown of collisions by emphasis area is used to identify the top areas of safety concern that require the involvement of engineering, enforcement, health, and education combined. In addition, a more detailed analysis looks for the over-representation of different collision types by emphasis area allowing agencies to identify locations where specific collisions are occurring at higher proportions than would statistically be expected. Example calculations are provided to illustrate over-representation, which can then be applied to emphasis area collisions.