The seminar will address two fundamental aspects related to the roadway safety management process: the network-wide road safety assessment and the safety effectiveness evaluation. The first activity undertaken in a cyclical roadway safety management is the network screening which is a process for reviewing a transportation network to identify and rank sites from most likely to least likely to realize a reduction in crash frequency with implementation of a countermeasure. So far, such a networkwide road safety assessment has been mainly implemented using reactive approaches, i.e., ex-post evaluation based on crash occurrence analysis. However, due to crash data limitations (availability, accuracy, randomness, timeliness, etc.), proactive approaches (i.e., ex-ante evaluation based on in-built design characteristics of the road) are gaining interest also at network level and currently demanded by the European legislation. Safety effectiveness evaluation is the last step of the management process and generically consists of an assessment of how crash frequency or severity has changed due to a specific treatment or a set of treatments or projects. Properly evaluating the effectiveness of implemented safety treatments is an important step in the overall safety management process since it allows assessing how well funds have been invested in safety improvements decisively influence future decision-making activities related to effective treatment definition and allocation of funds.
