CCF analysis in PSA applications from a licensee view
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B. Schubert
Abstract
In highly redundant systems CCF dominate the calculated unavailabilities. CCF contribute over 90% to the resulting core damage frequencies of some PRAs for German Nuclear Power Plants. Because the results of PRAs can lead to costly back fitting measures, it is essential to ensure these results. The principles of CCF analysis and the efforts to establish a comprehensive data base are described. In addition the utilities have undertaken efforts to develop concepts for defensive strategies and to introduce these measures in the plant operation in order to reduce the CCF probabilities. Unfortunately these efforts are yet not fully supported by the existing models.
Kurzfassung
In hoch redundanten Systemen dominieren GVA (Gemeinsam verursachte Ausfälle) die ermittelten Nichtverfügbarkeiten der Systeme. In Probabilistischen Sicherheitsanalysen für deutsche Kernkraftwerke tragen GVA z. B. zu über 90% zu den ermittelten Kernschadenshäufigkeiten bei. Da solche Analysen u. U. wesentliche Investitionen auslösen, ist eine Absicherung der Ergebnisse zwingend erforderlich. Der Beitrag beschreibt die Bedeutung der GVA Analyse sowie die Absicherung der Ergebnisse durch eine umfassende Datenerfassung. Aus Sicht der Betreiber stellen darüber hinaus die Maßnahmen zur Ermittlung von Einfluss- und Koppelungsfaktoren bei der GVA-Entstehung und die in den Anlagen ergriffenen Maßnahmen zur Verhinderung von GVA-Ereignissen einen entscheidenden Beitrag zur Reduzierung der GVA-Wahrscheinlichkeiten dar. Dies wird in den gegenwärtig existierenden GVA-Ansätzen zu wenig berücksichtigt.
References
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© 2006, Carl Hanser Verlag, München
Articles in the same Issue
- Contents/Inhalt
- Contents
- Summaries/Kurzfassungen
- Summaries
- Editorial
- Common cause failure analysis within the framework of probabilistic safety assessment
- Technical Contributions/Fachbeiträge
- Updated requirements on PSA methods and data for comprehensive safety reviews in Germany
- OECD/NEA International Common Cause Failure Data Exchange (ICDE) Project – insights and lessons learnt
- Protection against dependent failures, analysis of dependencies and derivation of CCF data
- Extension of the German database for common cause failure events
- International network on incorporation of ageing effects into PSA
- CCF analysis for new reactor designs
- CCF treatment in PSA: insights and recommendations from reviewing procedures
- Is mapping a part of common cause failure quantification?
- Further development of the coupling model
- The Process-Oriented Simulation (POS) model for common cause failures: recent progress
- CCF analysis in PSA applications from a licensee view
- Notes
- Radiation protection of outside workers
- Technical Contributions/Fachbeiträge
- Occupational exposure to natural radiation
Articles in the same Issue
- Contents/Inhalt
- Contents
- Summaries/Kurzfassungen
- Summaries
- Editorial
- Common cause failure analysis within the framework of probabilistic safety assessment
- Technical Contributions/Fachbeiträge
- Updated requirements on PSA methods and data for comprehensive safety reviews in Germany
- OECD/NEA International Common Cause Failure Data Exchange (ICDE) Project – insights and lessons learnt
- Protection against dependent failures, analysis of dependencies and derivation of CCF data
- Extension of the German database for common cause failure events
- International network on incorporation of ageing effects into PSA
- CCF analysis for new reactor designs
- CCF treatment in PSA: insights and recommendations from reviewing procedures
- Is mapping a part of common cause failure quantification?
- Further development of the coupling model
- The Process-Oriented Simulation (POS) model for common cause failures: recent progress
- CCF analysis in PSA applications from a licensee view
- Notes
- Radiation protection of outside workers
- Technical Contributions/Fachbeiträge
- Occupational exposure to natural radiation
