A cyclotron is an electrical apparatus that accelerates ions (charged atoms). It contains no nuclear fuel. The radioactive species it produces have short life spans (the isotope having the longest half-life, produced in significant quantities, is sodium-22, Na-22).

The quantities of radioactivity manipulated are comparable with those used routinely by a hospital. However the project incorporates risk management upstream.

The risks relating to the cyclotron are of two types:

  • Exposure of those working in the facility to radiation. The way of protecting oneself against this risk consists in fitting lead or concrete screens between the source of radiation and the staff. The cyclotron is protected by very thick concrete (up to 3.7 meters thick); guaranteeing compliance with regulations both inside the facility and outdoors. This is not unusual, and many medical particle accelerators (at the cancer treatment center for instance) are protected in this manner.
  • Dispersion of radioactive material in the facility then possibly in the environment. The way of protecting oneself against this risk consists in confining the radioactive material with a series of barriers. The radioactive material is manipulated in sealed containers, which in turn are manipulated inside sealed isolators, all this in a building in negative pressure with ventilation filtered before release. Radioactive material is transported in appropriate shock-resistant containers subject to specific regulations.


The facility is also under constant surveillance: the level of radiation in the rooms, detection of leaks of radioactivity, monitoring of released ventilation. If there is a problem, the cyclotron is immediately shut down. Workers in the controlled area are under heightened medical supervision by the medical officer. In the restricted access area, they wear passive and operational dosimeters and are checked before they leave their work area.


With regard to official controls, the facility is authorized by the ASN (French Nuclear Safety Authority) to carry out nuclear activities. Furthermore, the construction was subject to prefectural authorization after a public inquiry, which included an impact assessment and a safety assessment. The impact assessment is updated on a regular basis.

The facility requires neither the establishment of easements or hazard zones nor an external emergency plan.