Results of determination of irradiation conditions for vessel internals of VVER-440 reactor No. 1 and 2 at Rovno Nuclear Power Plant, obtained by specialists at Institute for Nuclear Research Kyiv, Ukraine, and Nuclear Research Institute Rez, Czech Republic, are presented. To calculate neutron transport, detailed calculation models of these reactors were prepared. Distribution of neutron flux functionals on the surface of reactor VVER-440 baffle and core barrel for different core loads was studied. Agreement between results obtained by specialists at Institute for Nuclear Research and at Nuclear Research Institute is shown.