Development of an Integrated PSA Software Tool for Internal and External Events

Probabilistic Safety Assessment (PSA) is an analytical technique for assessing the risk by integrating diverse aspects of design and operation of a plant. In general Event Tree (ET) and Fault Tree (FT) approach is used to quantify the risk of the plant. The ET/FT can vary from a simple to large diagrams depending on the size and complexity of the systems and the plant. These ET/FTs are evaluated through Minimal Cut Sets (MCS).Generation of MCS also varies depending on the complexity of the problem and sometimes it is a time consuming process. Hence, now a days, several software tools are available to construct the ET/FTs, from there to generate the MCS and there by evaluating the risk. Each and every tool has certain limitations. In order to overcome the limitations of the existing tools and to suit to the requirements of various industries risk analysis, an indigenous software tool is being developed which can integrate both internal and external events. In this paper various developmental aspects, features and modules of the tool has been discussed.