On September 30, 2024, as part of the preparation for an intervention, a responder notably put in place a lead biological protection mattress and moved flexible protection.
During the radiation protection check carried out at the exit from the reactor building, contamination was detected on his right hand. The agent was taken care of by the risk prevention service, which removed the radioactive particle causing this contamination. However, poor application of the worker’s treatment instructions led to a delay in the removal of this particle.
For workers likely to be exposed to ionizing radiation during their professional activity, the annual regulatory dose limits are, for twelve consecutive months, 20 millisieverts for the entire body and 500 millisieverts for an area of 1 cm² of skin.
The dose received by the worker was estimated by occupational medicine on the basis of unfavorable hypotheses in terms of duration of exposure. It is lower than the regulatory annual limit at skin level. However, the dose received to the skin exceeded a quarter of this annual limit.
The investigations carried out on the worker’s journey have highlighted that this contamination probably finds its origin in the activities carried out around the biological protection elements moved by the worker.
Due to exceeding a quarter of an annual regulatory exposure limit for a worker, this event was classified as level 1 of the ladder INES (International scale of nuclear and radiological events).
