Flavien Simon studied mathematics and fundamental physics at Ecole Polytechnique in France. After graduating from this school, Flavien decided to join French civil administration. I first became chief of a risk prevention department in a French regional administration, my team being responsible of the control of the hazards caused by industrial activities and their impact on the environment, between 2018 and 2021.

In January 2022 Flavin joined the French nuclear safety authority, becoming deputy director of the pressure vessels division. I became director of this division on November 2023. In this division of the ASN, we are in charge of the control of all matters related to the design, manufacturing and operation of pressure vessels and piping in civil nuclear sites. In the recent years, we have been particularly involved in the control of the manufacturing of the equipments of the EPR and EPR2 types of reactors (reactor pressure vessels, steam generators, piping of the main primary and secondary circuits), the stress corrosion cracking issue, or the aging of RPVs and cast stainless steel components.