An Overview of Main Impact on PRA Tasks in Order to Model Ageing Effects

This presentation discusses the implications on the individual tasks when performing a Probabilistic Safety/Risk Assessment (PSA/PRA) in order to model ageing effects. The discussion deals with the following aspects: 1) PRA/PSA data issues: - Initiating events (updating of Initiating Events (IE) frequencies and definitions) - Active components (choice of reliability models and parameters estimation) - Passive components (physical reliability models development) - Common Cause Failures (CCF) (parameters, intersystem failures) 2) PRA/PSA Tasks: - PRA/PSA main assumptions and inputs from the deterministic analyses and operation - List of Initiating Events and evaluation of their frequencies - Event Trees construction and definition of Success Criteria for the Fault Tree Analysis - Fault Tree Analysis - Integration of Fault Trees into Event Trees - Sensitivity and Uncertainty Analysis for PRA level 1 - Containment Event Trees - Implementation of changes into the model to consider external/area events - PRA level 3 and risk calculations - Introducing changes for other modes of operation and all radioactive sources - Sensitivity / uncertainty analysis for PRA - Review of results and preparation for their use into the decision making process, design optimization and other applications.

SERBANESCU Dan; 

2007-02-15

EC-JRC-IE

JRC34810