Cattenom Contamination Detected

The Corps grand-ducal d'incendie et de secours (Grand Ducal Fire and Rescue Corps, CGDIS) have confirmed that, on Thursday 2 February 2023, a radioactive particle was discovered on a worker at the Cattenom nuclear power station across the border (in France).

The worker had carried out logistics activities in several rooms in the reactor building of production unit no. 3, currently shut down for maintenance. During a safety check on leaving the nuclear zone, external contamination was detected on the worker's cheek.

The worker was immediately taken care of by the medical service of the plant, to carry out additional checks and treat the point of contamination according to the usual procedures. A radioactive particle was identified in his cheek and removed very quickly.

The employee's exposure is calculated from the level of radioactivity of the particle present on the skin and the time during which this particle was actually exposed to the employee. The calculation of exposure leads to a slight overrun of the annual regulatory limit known as the “skin dose” set at 500 millisieverts. The equivalent dose received by the worker for the whole body is very low, around 1 microsievert, i.e. 20,000 times lower than the regulatory annual limit.

For employees likely to be exposed to ionizing radiation during their professional activity, the annual regulatory dose limits are, for 12 consecutive months, 20 millisieverts for the whole body and 500 millisieverts for a surface area of 1 cm2 of skin.

According to medical advice, this event has no impact on the worker's health, given the relatively short duration of exposure and the very small size of the particle. As is the case when a regulatory threshold is reached, the employee will benefit over the next few months, as a precaution, from appropriate medical monitoring.

As soon as the contamination was detected, the premises in which the employee had worked were closed and checks were carried out. They did not show any trace of particular contamination, the origin of the event was therefore deemed to be an occasional contamination. No other employee present at the same time in the reactor building was detected to be contaminated by the control gates when they left the nuclear zone.

The management of the Cattenom power plant declared this event on 3 February to the Nuclear Safety Authority, as a significant level 2 radiation protection event (incident) on the INES scale, which has 7 levels, due to the exceeding of the annual regulation limit for the skin dose.