A ‘new’ Vision for Nuclear Reactor Safety

The paper deals with Nuclear Reactor Safety Technology (NRST) involving fission and water cooled or moderated reactors. NRST is established since several decades, starting from the discovery of nuclear fission. Well known events, the latest one being Fukushima, have challenged the future of nuclear technology and undermined the trust of the public, of the decision makers and even of the scientific community toward nuclear safety. Innovative ideas and proposals are possibly needed to restore the confidence and escape the irreversible loss of competence which also feeds the further degradation of the sustainability for this technology. A two-tier interconnected idea is outlined in the paper. On the one hand independent-mandatory safety analysis planned and performed according to the latest available developments in science and technology. On the other hand, feedback of analysis upon the design, construction and operation of any Nuclear Power Plant in terms of systems and related control: to this aim, characterization and continuous monitoring of expanded Safety Margins is established. The role of safety analysis as a key part of NRST is discussed first and the innovation connected with the words ‘independent’ and ‘(systematic) Best Estimate Plus Uncertainty’ is presented. The concept of continuously monitored extended safety margins is outlined in the second part of the paper