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DOE OSTI · 1261237

System Study: Isolation Condenser 1998-2014

Schroeder, John Alton
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Abstract

This report presents an unreliability evaluation of the isolation condenser (ISO) system at four U.S. boiling water reactors. Demand, run hours, and failure data from fiscal year 1998 through 2014 for selected components were obtained from the Institute of Nuclear Power Operations (INPO) Consolidated Events Database (ICES). The unreliability results are trended for the most recent 10 year period, while yearly estimates for system unreliability are provided for the entire active period. No statistically significant increasing trends were identified. A statistically significant decreasing trend was identified for ISO unreliability. The magnitude of the trend indicated a 1.5 percent decrease in system unreliability over the last 10 years.

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21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTSBWR TYPE REACTORSDEMANDEVALUATIONFAILURESISOLATION CONDENSERSRELIABILITY

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Schroeder, John Alton. 2015-12-01. System Study: Isolation Condenser 1998-2014. https://doi.org/10.2172/1261237

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