Proceedings of the

The 33rd European Safety and Reliability Conference (ESREL 2023)
3 – 8 September 2023, Southampton, UK

The Impact of Seismic Events on Human Reliability and Phoenix HRA Methodology

Anna Cosmin-Spanoche1,a, Marilia Ramos1,b, Ali Mosleh1,c and Kanoko Nishiono2

1Garrick Institute for the Risk Sciences, University of California, Los Angeles, USA.

2Japanese Nuclear Regulation Authority.


Risk assessment of Nuclear Power Plants (NPPs) through Probabilistic Risk Assessment (PRA) and Human Reliability Analysis (HRA) is relatively mature for internal events - those that start inside the power plant it serves. Advances have also been made for external events, such as earthquakes and floods. Yet, particularly for HRA, more research is needed to understand the impact of seismic events on human performance and the adequacy of currently used HRA methods. According to a report from the International Atomic Energy Agency, around 20 percent of nuclear reactors worldwide operate in areas vulnerable to earthquakes, so understanding seismic impacts on HRA is significant to prevent human errors and for realistic Human Error Probability (HEP) assessment.

Seismic events may add failure modes and human and organizational factors that are not fully addressed by internal event models. This paper will investigate the unique factors associated with seismic events, and how they can be incorporated in the Phoenix HRA Methodology.

Keywords: Human reliability analysis, Seismic events, Phoenix HRA, Nuclear power plants.

Download PDF