TVO/I/II PSA programme

the first step was the probabilistic analysis of core melt due to loss of reactor coolant, internal transients and loss of external 400 kV grid. The analysis of fires and floods will be finished in 1990. The shutdown and operational mode change PSA will be reported by June 1991. Probabilistic analysis of containment integrity and radioactive releases will be performed after the shutdown analysis finished. Among the main goals of the programme are identification and priorization of those human interactions and dependences which are most important to the core melt probability. The utility's own technical and operational staff has performed due to educational purposes 80 per cent of the analyses. The results of PSA will be used for example in planning of simulator training cases. Optimination of Technical Specifications is also possible when using the PSA-models in connection with specialc omputer codes