Event Tree Calculations Overview
Using event trees, you can perform both qualitative and quantitative analyses. You can perform a qualitative analysis prior to the entry of calculation data in the properties for the columns and branches. You can perform a quantitative analysis only after entering calculation data in the properties for the columns and branches.
• Qualitative analysis determines the minimal cut sets of the event tree based on failure and success logic. A cut set is a set of events that cause the top event to occur. A minimal cut set is the smallest set of events, which, if they all occur, cause the top event to occur. In the FTA module, the term ‘cut set’ refers to the minimal cut set.
• Quantitative analysis uses the reliability and maintainability information entered in the properties for the columns and branches to calculate the probability of occurrence of the minimal cut sets and the top event.
You specify information about the results to calculate on the
Event Tree page in the
Calculate window. For more information, see
Event Tree Calculate Property Page.