In this study, a methodology is outlined to estimate the importance of multi-unit accidents for a site with more than one reactor unit. The suggested approach is based on: - Identification of dependencies - Qualitative and quantitative screening - Estimation of frequencies/probabilities for screened in dependencies - Calculation of the Multi-Unit Core Damage Frequency (MUCDF) or Multi-Unit Large Early Release Frequency (MULERF) using primarily conditional quantification of single unit models (together with the frequency/probability of the dependence) - Sum of the MUCDF/MULERF for the identified dependencies to estimate the total MUCDF/MULERF The approach is considered a conceptual approach, and there are a number of outstanding issues that could be studied further. Most importantly, the approach needs to be validated using full scope PRA models.
|Publisher||VTT Technical Research Centre of Finland|
|Number of pages||29|
|Publication status||Published - 2017|
|MoE publication type||D4 Published development or research report or study|
|Series||VTT Research Report|
- multi-unit probabilistic risk assessment
Tyrväinen, T., Häggström, A., Bäckström, O., & Björkman, K. (2017). A methodology for preliminary probabilistic multi-unit risk assessment. VTT Technical Research Centre of Finland. VTT Research Report, No. VTT-R-00086-17 http://www.vtt.fi/inf/julkaisut/muut/2017/VTT-R-00086-17.pdf