A formal approach to causal analysis based on STAMP (CAST)

In the context that major accidents are mostly in consequence of complex factors interact with each other and the traditional accident analysis methods are no longer adequate to the modern complex socio-technical systems, a new accident model called STAMP and further an approach to accident analysis called CAST are presented. This paper proposes a formal approach to CAST, which emphasizes detailed description of the relationship between unsafe control actions of components, and formal specification and verification based on the model of the relationship using NuSMV. The result can clearly indicate the accident causation traces, revealing the interactions of components that eventually lead to the accident. Finally, a case of Yichunair crash accident is mentioned to verify the validity of the approach.