Objective provision tree application to the effectiveness evaluation of accident management guidelines

After the Fukushima accident in 2011, various lessons and safety enhancement action items were announced by national regulatory bodies. Among those items, the enforcement of procedural efficiency verification for accidents management guidelines including emergency operating procedures (EOPs), severe accident management guides (SAMGs) and extensive damage mitigating guidelines (EDMG) if applicable, was raised. The Objective Provision Tree (OPT) method is a top down approach which starts from the level of Defense in Depth (DiD), objectives and barriers, safety functions, challenges, mechanisms and finally ends with provisions. The benefit of OPT application to safety concerns includes that the OPT enables the comprehensive review for the verification of consistency and integrity of safety requirements for a specific safety issue. In this study, the preliminary framework for the application of OPT to the effectiveness evaluation of accident management guideline was introduced