Modelling integral risk assessment (MOIRA): Experiments on the Dutch railway departure process

Risk assessment is mostly document-based at this moment. In this paper, we present a study to compare two ways of integral risk assessment of the Dutch railway departure process. First, a document-based risk assessment about the departure process executed by NS in 2011. Second, a risk assessment about this same departure process with modelling of integral risk assessment (MOIRA). The aim is to measure and compare four key performance indicators: (1) validity of the risk assessment elements, (2) consistency of the data processing, (3) clarity of the boundaries, and (4) comprehension of the overall safety architecture. For this purpose, we have designed experiments that included direct, detailed observations in which we controlled the execution of performing risk assessment tasks. In total, twelve test sessions were performed, with in total 42 participants. Data was collected through the month of January 2019. In the end, we compare the two, to see if there are any objective differences, and also, we validate their usability by surveying the findings of the participants, resulting in a fifth KPI.