A new index to evaluate the safety performance level of railway transportation systems

In last years, the number of journeys on the European rail network is constantly increasing with consequent jeopardising of safety for operators and passengers. In this context, Decision Support Systems (DSSs) can be very helpful in managing safety performance level of the railway transportation system based on precursor analysis. In related literature, there are many studies on the precursor analysis and approaches to evaluate suitable safety indexes. On the other hand, a comprehensive multi-methodological approach including precursors analysis, a calibration of a safety index implemented in a DSS has not yet been attempted in related literature. In this paper an optimization-supported Analytic Hierarchy Process (AHP) is used to define a safety index implementable in a DSS for the railway transport system, considering the damage precursors in both the railway infrastructure and the train equipment. The definition of the index includes three synergistically related techniques: i) an AHP procedure to analyse the complexity of the problem and the precursors involved in potential damage; ii) a targeted data extraction from of the European Railways Agency (ERA) regarding the railways precursors and accidents; iii) a mathematical optimization approach to consider quantitative data in the weights calibration. The resulting index and DSS can be extensively and fruitfully applied by researchers and practitioners in order to assess the safety performance level of a railway network through detection of accidents precursors.