During ongoing maintenance at the Cattenom nuclear power plant, an isolated radiation exposure incident occurred involving an employee who was reportedly exposed to increased radioactive contamination. According to the French operator EDF, the worker entered the reactor core area of Unit 3 during the night of 9 to 10 June, and became contaminated in the process.
The contamination was detected during routine checks as the employee exited the reactor building, the first safety barrier before leaving the controlled area. Radioactive particles were found on his face, prompting immediate removal by a specially trained staff member. The worker was then taken to the plant’s medical service for further evaluation and will be closely monitored over the coming months as a precaution.
EDF clarified that this event is classified as a Level 2 incident on the International Nuclear Event Scale (INES), which ranges from Level 0 (no safety significance) to Level 7 (major accident). This classification is due to the employee’s exposure exceeding the annual regulatory skin dose limit of 500 millisieverts – a limit designed to protect workers from harmful radiation effects.
During the incident, the worker was laying lead mattresses inside the reactor building of Unit 3, which is currently shut down for maintenance. The exposure was calculated based on the radioactivity level of the particles on the skin and the duration of exposure. While the annual whole-body limit for radiation workers is 20 millisieverts, localised skin exposure can be higher, with 500 millisieverts allowed per 1cm² area.
Importantly, the risk prevention department inspected the working area and found no traces of lingering contamination, indicating the event was a one-time, localised contamination. No other workers present at the time showed signs of contamination when passing through security gates upon leaving the controlled zone.
EDF reported the incident to the Nuclear Safety and Radiation Protection Authority on 11 June, describing it as a significant radiation protection event. The company reassures that all safety protocols were followed, and ongoing medical supervision will ensure the affected employee’s health is carefully managed.
