What roles for risk imagination in risk assessment

This paper presents the findings of an investigation that was carried out following a railway accident: the derailment of a freight wagon. The derailment occurred because the excess of the chains used to secure the equipment loaded on the wagon, fell through holes in the wagon floor and became tangled with a part of the track that was not properly installed. The accident was thus caused by a combination of factors for which the railway undertaking (the company operating the wagon) was responsible and factors for which the infrastructure manager (which builds and maintains the track infrastructure) was responsible. In the course of the investigation, some inconsistencies were found in the risk analyses carried out by the infrastructure manager and the railway undertaking, which did not identify the risk of such an accident arising from the hazards identified by the investigating committee. The investigating committee concluded that the risk assessment committees would have needed "imagination" to identify these hazards. We discuss the concept of risk imagination, as proposed by N. Pidgeon and M. O’Leary, its usefulness in creating foresight concerning safety, and organizational features that could enhance the ability to identify novel accident scenarios inthe railway sector.