- Volume 25 Issue 3
In order to provide the necessary operation flexibility during the Nuclear power operation, the extension of existing allowed outage time(AOT) is needed. The extension of AOT affects the Nuclear power plant safety. The validity of changed technical specification requirements should be proved by the safety assessments. In this paper, we evaluated the extension of emergency diesel generator AOT for a single inoperable emergency diesel generator(EDG) from 3days to 7days, 10days and 14days. Finally, the AOT extension contributes the NPP performances through decreasing the unexpected plant trips, reinforcing maintenance and avoiding risks due to unnecessary operation mode changes when the NPP is under the surveillance tests or maintenance.
risk-informed;diesel generator;allowed outage time;safety assessment
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- KHNP, Safety Analysis for Containment ILRT Interval Extension of PWR, 2007. 9.
- KHNP, Optimization of Allowed Outage Times for Kori Units 3&4 and Yonggwang Units 1&2, Oct. 2007.
- USNRC, An Approach for Using Probabilistic Risk Assessment in Risk-Informed Decisions on PlantSpecific Changes to the Licensing Basis, Regulatory Guide 1.174, 1998.
- USNRC, An Approach for Plant-Specific, RiskInformed Decision-making Technical Specifications, Regulatory Guide 1.177, 1998.