Using Reason’s Model of Organisational Accidents in Formalising Accident Reports

Abstract: This paper proposes a method for analysing what are called organisational accidents. The first step of the method involves using Reason’s model of organisational failures. This provides heuristic guidance in identifying both the active and latent conditions that lead to major failures. The second step involves applying formal methods to support a detailed analysis of each latent and active condition. The method is demonstrated on a case study: the railway accident at Watford Junction in the United Kingdom. Analysis of the formal model helps to identify organisational factors that might have prevented the accident. It also helps to identify weaknesses in the report itself. In particular we argue that a signalling standard was misunderstood, the consequences of which could lead to another serious accident.