International validation of safety analyses for nuclear power plants

Paper describes the participation of 'J.Stefan' Institute in international standard problems for validation of modeling and programs for safety analysis. Listed are main international experimental facilities for collecting data basic for understanding of physical phenomena, code development and validation of modelling and programs. Since the results of international standard problem analyses are published in a joint final report, it is simple to asses the conformance of the results of a particular group with the experiment. Good results from three international exercises done so far, have encouraged the group to currently participate in OECD-ISP-22 which is a model of the Italian three loop PWR. (author)