| Abstract: | This paper describes a system of computer codes used for the generation and the analysis of event trees. These codes can be used to analyze event trees of 1,000 to 10,000 events and allow individualization of all the event sequences that lead to each accidental condition, within given probability intervals. They also provide a check for the correctness of the model, and assure the exhaustivity of the analysis and of its logical implications. Moreover, the methods assist in the solution of the fault tree that is developed, taking each plant's accidental condition as a top event and individualizing all the event sequences that lead to it. These codes also show, in the performance (capability and reliability) definition phase, the conditions of success for a system or a component, both in operation or on call. Some results of these methods as they apply to the safety risk analysis of a research program in the nuclear field (supersara program) are described. |
