Radioactivity in the primary circuit of the fast BOR-60 reactor

The experimental results of the accumulation and distribution study of radioactive corrosion and fission products in the primary circuit of the BOR-60 are presented. It is shown that after the reactor prolonged operation with defective fuel elements, the radiation conditions at repair works are determined by the fission radioactive products. The most radiation-dangerous nuclides are 137Cs, 140Ba, 95Nb. The BOR-60 cold trap purifies the coolant practically completely from iodine radionuclides by 20-90% from esium radionuclides, by 20-30% from antimony and cobalt. At reactor operating approximately with 1% of defective fuel elements, the dose rate in the primary circuit boxes after sodium draining from the reactor loops equals 70-100 μRxc-1, the radiation conditions at the NPP BOR-60 for the whole operation period remaining satisfactory. NPP radioactive releases of 41Ar do not exceed 500 Ci a year