Current perspectives in nuclear safety R and D. [PWR; BWR]

General guidelines and major current themes of nuclear safety research at EPRI are presented. Such themes include the importance of analyzing small-break and other lesser accidents; natural circulation as a cooling mode; adequate prediction of plant transient behavior; analysis of degraded core; realistic estimates of radioactive releases; analytic and experimental assessment of structural integrity; and risk assessment as a useful tool for reactor design and operation. Recent advances and current efforts are summarized in the following categories: collection of data and their analysis in operating nuclear plants; scaled thermal-hydraulic tests; large-scale demonstrations; realistic assessment of accident effects and consequences; and safety quantification and the assistance provided to the operator in the control room of nuclear plants.