Currently, researchers tend to focus on dynamic risk assessment and management rather than static or traditional risk assessment, and also risk-based decision making . A number of dynamic methodologies have been developed, which mainly include cellular automation , dynamic graph models , and stochastic simulation . For dynamic systems, these dynamic methodologies can support swift operational decisions to maintain the process within the safer operating limits, thus preventing untoward incidents/accidents . However, the execution of a dynamic model usually requires huge computation time . The utility of dynamic methodologies is usually limited by the scarce computing resources.