Accident causation models: A comparison of SCM and 24Model

The Swiss Cheese Model (SCM) and 24Model have proved over the years to be lasting influences for many researchers and practitioners in various safety areas. However, as one practical tool for accident analysis, a gap still exists for whether these two models are consistent in current studies. A theoretical comparison of these two models to reveal constructive foundation, related concepts, correspondence to each level of cause-effect and characteristics of sub modules were presented. The basic structure of the two modular models is consistent and each sub module can match. The foundation of the two models is different, reflecting the differences between Eastern and Western cultures. 24Model overcomes the fuzziness of SCM model classification and divides organizational factors into two stages: safety management system and safety culture and refines the meaning of accident and hazard. Hazard identification based on SCM is presented at the design and commissioning of the system, while the identification of 24Model following PDCA cycle, which is an continuous improvement throughout the entire life cycle of the system. In conclusion, 24Model is a deepening and development of SCM, and explicit taxonomy for individual and organization is proposed by integrating factors on SCM. The comparisons will build a bridge of communication and exchange between East and West accident causation theories and will lead to more knowledge of the causes to the accident, placing focus on need for improved organizational behaviors, more efficient safety management systems and safety culture in companies.