| 1. |
- Bladh, K., et al.
(författare)
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An approach to analyse human reliability during refuelling outage of a nuclear power plant
- 2007
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Ingår i: Proc. of Enlarged Halden Programme Group Meeting.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Human reliability analysis (HRA) constitutes a central role in the probabilistic safety assessment (PSA) for the low power and shutdown period of a nuclear power plant. This is because a large number of operative and maintenance activities take place during a refuelling outage when the plant, to a great extent, is disassembled, maintained, and then reassembled back to operational mode. The paper presents the HRA approach used in the shutdown PSA for Forsmark 1/2 and 3 nuclear power units in Sweden. Challenges of the analysis comprises handling the large scope of activities to be analysed, development and use of a quantification method consistent with the full power PSA, and integration of HRA with the “technical” part of PSA. Experiences from the analysis and results will also be discussed.
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| 2. |
- Bladh, K., et al.
(författare)
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An evaluation of the enhanced Bayesian THERP method using simulator data
- 2009
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Ingår i: SAFETY, RELIABILITY AND RISK ANALYSIS. - London : Taylor & Francis Group. ; , s. 227-232
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The Enhanced Bayesian THERP (Technique for Human Reliability Analysis) method has been successfully used in real PSA-studies at Finnish and Swedish NPPs. The method offers a systematic approach to qualitatively and quantitatively analyze operator actions. In order to better know its characteristics from a more international perspective, it has been subject to evaluation within the framework of the "HRA Methods Empirical Study Using Simulator Data." This paper gives a brief overview of the method with major findings from the evaluation work including identified strengths and potential weaknesses of the method. A number of possible improvement areas have been identified and will be considered in future development of the method.
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| 3. |
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| 4. |
- Cronvall, O., et al.
(författare)
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Development and application of risk informed in-service inspection analysis procedures
- 2006
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Ingår i: SAFIR, The Finnish Research Programme on Nuclear Power Plant Safety 2003–2006. - : VTT. - 9789513868864 ; , s. 92-102
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Characteristics and development of risk informed in-service inspection (RI-ISI) methodology for nuclear piping systems are examined in this report. This involves applying the combination of probabilistic fracture mechanics (PFM) and Markov system analyses, and by refining an existing and commonly applied risk analysis procedure. The applicability of the developed risk matrix approach was examined as a pilot study performed to a piping system in an existing Finnish nuclear power plant (NPP).
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| 5. |
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| 6. |
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| 7. |
- Holmberg, Jan-Erik, et al.
(författare)
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Criteria for assessment of results from level 2 PSA
- 2008
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Ingår i: Proc. of PSAM 9 — International Conference on Probabilistic Safety Assessment & Management, 18–23 May 2008, Hong Kong, China, IAPSAM — International Association of Probabilistic Safety Assessment and Management.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Probabilistic criteria are used to judge the acceptability of PSA results. Highest levelcriteria set limits to acceptable societal risk, which requires performance of level 3 PSA. In manycountries — including e.g. Finland and Sweden — performance of level 3 PSA is not required, andprobabilistic decision criteria (limits or targets) are defined only at core damage frequency and largerelease frequency level. The definition of probabilistic criteria for level 2 PSA has been one of the keyissues discussed in the Nordic study on validation of safety goals. There is a need to discuss and definemore precisely the decision criteria related to unacceptable releases, as they seem to be understooddifferently in different organizations. For instance, the inclusion or exclusion of long-term effectsmakes a big difference as well as the inclusion or exclusion of the affected population in neighboringcountries. This paper presents the summary and conclusions from the Nordic study with respect toprobabilistic criteria for level 2 PSA. In addition, the interpretation of the release criteria (<100 TBq,Cesium-137) defined in the Finnish regulatory guide YVL 2.8 will be presented by means of off-siteconsequences. Such assessments of the environmental consequences can be used as references tovalidate safety goals related to CDF and large releases as surrogates of societal risk.
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| 8. |
- Holmberg, Jan-Erik, 1964-, et al.
(författare)
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Interdisciplinary expert collaboration method (IECM) for supporting human reliability analysis in fire PSA
- 2005
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Ingår i: Proc. of International Topical Meeting on Probabilistic Safety Analysis. San Francisco , CA, 11–15 Sept. 2005. - : American Nuclear Society. ; , s. 1056-1061
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Konferensbidrag (refereegranskat)abstract
- The Interdisciplinary Expert Collaboration Method (IECM) has been developed for contributing to the development of risk-informed management of fire situations at nuclear power plants. The IECM provides a systematic practice and shared conceptual tool for the co-operation of experts from different domains, related to the management of fire situations. It is used for improving support for the management, but it can also contribute to the fire risk analysis by improving the realism of the human reliability analysis (HRA). The paper compares the IECM with the recommendations of the NUREG-1792 document (Good Practices for Implementing Human Reliability Analysis). Even though the method does not yet support the quantification of human error probabilities, it can be utilized in HRA in several manners.
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| 9. |
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| 10. |
- Holmberg, Jan-Erik
(författare)
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Principles and practices of risk-informed safety management (PPRISMA)
- 2006
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Ingår i: SAFIR, The Finnish Research Programme on Nuclear Power Plant Safety 2003–2006. - : VTT. - 9789513868864 ; , s. 353-360
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- The PPRISMA project deals with both risk-informed decision making and methods for risk assessment. Approaches have been developed to support maintenance and operability planning, management of fire situations and safety classification. Methods for the reliability assessment of computer-based systems and long term mission reliability analysis have been developed. In addition, the research activities are carried through international co-operation.
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