Abstract: In order to explore deep organizational cause mechanism for serious railway accidents, an ISM-24Model analysis framework was built by integrating 24Model and ISM. Firstly, individual and organizational factors were identified following 24Model logic recognition procedure. Then, a comprehensive influence matrix of organizational factors based on ISM method combined with DEMATEL was established to calculate reachability matrix, and relative importance and hierarchical structure among organizational factors were obtained. Finally, with "10·21" accident of Taiwan Railway as an example, 33 unsafe personal factors and 14 organizational factors were identified in the framework. The analysis results of influence relationship and hierarchical structure of organizational factors show that lack of understanding of safety input is a core organizational factor that leads to accidents, while safety training system is the most centralized one that is affected by adverse effects. Therefore, taking diversified measures to rectify missing organizational factors can avoid recurrence of accidents from root. The conclusion shows that ISM-24Model is an effective supplement to 24Model as it can effectively explore law of organizational causes in accidents.

Key words: interpretive structural model (ISM), 24Model, serious railway accidents, deep organizational cause, decision making trial and evaluation laboratory(DEMATEL), “10·21” Taiwan railway accident