Neutron measurements in Spanish nuclear power plants with a Bonner sphere spectrometer system.

Neutron spectrometric measurements with an active Bonner Sphere System (BSS) allowed us to determine the reference dosimeter values in Ascó I and II and Cofrentes (PWR, BWR) Spanish nuclear power plants. Under a request from the Spanish National Nuclear Safety Council, the UAB group was in charge of characterising the neutron fields at several measurement points (a total of 10) inside the containment building of these nuclear installations using an active BSS and a home-made MITOM unfolding code. The measurement results in the three installations confirm the presence of low-energy neutron components in almost all selected points. This developed BSS can be considered as a reference system in neutron radiation protection when defining the corresponding protocols for a correct personal dosimetry in nuclear power plant installations.