Identification of Risk-Significant Components in Nuclear Power Plants to Reduce Cs-137 Radioactive Risk. (July 2021)

• Record Type: Journal Article
• Authors: Cho, Jaehyun; Han, Sang Hoon
• Is Part Of: Reliability engineering & system safety. Volume 211(2021)
• Publication Date: 2021-07
• Subjects: Probabilistic safety assessment -- Minimal cut set -- Basic event -- Risk importance measure -- Fussell–Vesely -- Risk achievement worth -- Cs-137; Reliability (Engineering) -- Periodicals; System safety -- Periodicals; Industrial safety -- Periodicals; Fiabilité -- Périodiques; Sécurité des systèmes -- Périodiques; Sécurité du travail -- Périodiques; 620.00452
• DOI: 10.1016/j.ress.2021.107613
• Languages: English
• ISSNs: 0951-8320

Abstract

Highlights: Cs-137 risk quantification using release frequency and Cs-137 radioactivity Identification of all accident scenarios with a Level 1 and 2 PSA linked model Quantification of key risk importance measures using Cs-137 risk Application study on OPR-1000 internal event Level 1 and 2 PSA model Top 20 basic events in FV importance, RRW, and RAW using Cs-137 risk Abstract: The amount and frequency of Cs-137 release in a nuclear accident are regulated to enhance environmental radiation protection. While significant improvements have been accomplished, including the preparation of severe accident mitigation equipment and systems to satisfy Cs-137 regulations, no attempt has yet been made along these lines to manage the structures, systems and components (SSCs) in nuclear power plants. Therefore, this paper proposes a new approach to identify the significant SSCs by quantifying related risk importance measures using release frequency and Cs-137 radioactivity. The new approach includes a Level 1 and Level 2 probabilistic safety assessment (PSA) linked model to obtain the frequency and Cs-137 radioactivity in all accident scenarios. The developed approach was applied to an OPR-1000 full-power internal events PSA model, and as a result, the top 20 SSCs were identified based on Fussell–Vesely importance, risk reduction worth, and risk achievement worth measures. The new approach can support risk-informed management for not only Cs-137 regulations but also public risk by using early and latent cancer fatalities.