Dynamic Modeling of Field Operators in Human Reliability Analysis: An EMRALD and GOMS-HRA Dynamic Model of FLEX Operator Actions

Abstract

In response to the Fukushima Dai-ichi accident, the Nuclear Energy Institute developed guidance for establishing flexible coping strategies for beyond-design-basis external events (BDBEE). These coping strategies, termed FLEX, consist of additional equipment and procedures to safeguard the plant in the event of a BDBEE. Little research has been performed to model the FLEX activities with dynamic human reliability analysis (HRA). The research described here sought to build an HRA model of FLEX activities for a station blackout event, add dynamics to the model using the GOMS-HRA method, and evaluate the feasibility and ease of building the dynamic model within an existing dynamic PRA tool called Event Modeling Risk Assessment using Linked Diagrams (EMRALD). The modelling effort was successful in building a dynamic HRA model of FLEX activities within the existing dynamic PRA tool and highlighted several potential improvements to enable EMRALD to better incorporate HRA more effectively within its framework.