Common cause failure modelling

Full text: Common cause failure modeling is the best way to communicate the qualitative and quantitative data, required to protect against catalectic failure during normal operation of a nuclear power plant, starting from design phase to decommissioning phase. Also, it is the key to ensure an optimized maintenance and operation all the NPP life-time long under main three principles, concerning: - control and maintenance of nuclear power reactor in all the functioning states; - cooling the reactor core during any transient and normal state; - the radioactivity level inside a guaranteed and fail-safe physical area. The subject of this paper is describing a common cause failure modeling structure. Results and reports of such a modeling could be used to comply with the national regulatory body requirements. Based on numerical values related to the safety analysis, operating and maintaining experience, principles and policies, any activity concerning commercial functioning of a NPP should comprise a good planning and a strong-based safety culture with respect of designer intention. Common cause failure modeling by its screening phase, detailed quantitative and qualitative phase leads to the final goal: operating NPP under reliable and safe conditions. (author)