POST-ANNEALING EX-VESSEL DOSIMETRY AT LOVIISA 1 - AN INTERNATIONAL EXERCISE

摘要

In order to improve the assessment of the post-annealing neutron exposure an ex-vessel (cavity) irradiation was carried out during cycle 22 (1998-99) at unit 1 of the Loviisa NPP (type VVER 440) in Finland. A dosimeter holder rack was designed and built by Skoda JS a.s., Czech Republic. Dosimeter sets were provided by VTT, Skoda and JRC/NRG Petten, the Netherlands. Some of the dosimeters were counted at Skoda and NRG Petten in addition to VTT. The large number of reactions used provided a good basis for spectrum adjustment. The results of the intercomparison are presented as well as a critical assessment of the materials and methods used. A similar irradiation is planned for Loviisa unit 2 during 2002-03.