Development of the advanced procedure for emergency operation using task allocation and synthesis of PRA results

An advanced emergency operating procedure (AEOP) for emergency operation is developed and discussed by focusing attention on the importance of the operator's role in emergency conditions for nuclear power plants (NPPs). Progress and improvement in the procedures now seem to be at a standstill insofar as the remaining problems cannot apparently be solved using the conventional approach. To overcome the complexity of emergency operating procedures (EOPs) and maintain the consistency of action steps according to plant emergency conditions, operator tasks are allocated according to their duties in the AEOP and a computerized operator aided system (COAS) is developed as an alternative to reduce the operator's burden and provide the detail action procedures. The PRA (Probabilistic Risk Assessment) results are synthesized in the AEOP using the event tree (ET) to give awareness and prediction of accident progression in advance dynamically and COAS is implemented on a SUN-4/75 workstation using C and Quintus TM prolog language. Finally, the time response for completing the required action is observed to evaluate the impact of the AEOP with COAS on operator performance during the loss of offsite power (LOOP) scenario with the full scope simulator of NPP at Kori. The results indicated that operator actions using AEOP are not only more consistent but are also able to provide earlier termination and mitigation of accidents.