Lightning risk assessment evaluation on French nuclear power plants

On one side, lightning risk assessment is carried out on French nuclear power plants since 2002. And on the other side, all kinds of incidents are collected since 1980. It is a good opportunity to evaluate the standardized risk assessment calculation with reality in that case. So we carried out calculation of all risk components on all structures of all sites and summarized the results to compare it with the real damage frequency between 1980 and 2012. It appears that a strict application of IEC 62305-2 hugely overestimate the damage frequency. We tried to analyze and understand the differences, and we proposed some evolutions to reach a satisfying adequacy between calculation and reality in the future.