Evaluation of Allowed Outage Times From a Risk and Reliability Viewpoint
- 1. Safety Information Research Center, Nuclear Power Engineering Corporation (Japan)
Description
With respect to the safety systems during nuclear plant operation, the Safety Regulation (Technical Specification) provides allowed outage times (AOTs) for failure of one train or one component of standby systems and the surveillance test intervals (STIs) which are applied to the remaining systems during such AOTs. The effectiveness of the AOTs and STIs provided as the limiting conditions for operation (LCO) on plant safety and reliability has been evaluated with probabilistic method. The plant safety systems are designed to prevent and mitigate plant transients and accidents. To confirm this, plant behavior analysis is performed about the transients and accidents postulated as the design based events (DBE), and analyzed result is confirmed not to exceed the safety design criteria. Therefore we considered the LCO has firm connection with the criteria and it should be referred when the effectiveness of LCO is evaluated. The effectiveness of the AOTs and STIs is investigated using the system's unavailability and total probability violating the criteria for plant safety design. In addition, a certain value of the probability for the safety operation criteria was postulated to assess the effect of the AOTs and STIs
Additional details
Publishing Information
- Imprint Title
- Proceedings of the workshop on reliability data collection
- Imprint Pagination
- 260 p.
- Journal Page Range
- p. 150-166
- Report number
- NEA-CSNI-R--1998-10
Conference
- Title
- Workshop on reliability data collection
- Dates
- 21-23 Apr 1998
- Place
- Budapest (Hungary)
INIS
- Country of Publication
- Nuclear Energy Agency of the OECD (NEA)
- Country of Input or Organization
- Nuclear Energy Agency of the OECD (NEA)
- INIS RN
- 43127872
- Subject category
- S22: GENERAL STUDIES OF NUCLEAR REACTORS;
- Resource subtype / Literary indicator
- Conference
- Descriptors DEI
- AVAILABILITY; DATA BASE MANAGEMENT; FAILURES; INFORMATION RETRIEVAL; INFORMATION SYSTEMS; JAPAN; NUCLEAR DATA COLLECTIONS; NUCLEAR POWER PLANTS; OUTAGES; PROBABILISTIC ESTIMATION; REACTOR COMPONENTS; REACTOR MAINTENANCE; REACTOR OPERATION; REACTOR SAFETY; RELIABILITY; RISK ASSESSMENT; SAFETY ANALYSIS; STATISTICS; SYSTEM FAILURE ANALYSIS
- Descriptors DEC
- ASIA; CALCULATION METHODS; DEVELOPED COUNTRIES; MAINTENANCE; MANAGEMENT; MATHEMATICS; NUCLEAR FACILITIES; OPERATION; POWER PLANTS; SAFETY; SYSTEMS ANALYSIS; THERMAL POWER PLANTS