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Division Spotlight
Operations & Power
Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
Meeting Spotlight
ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Latest News
Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
Christopher Hunter, Ching Ng, Mehdi Reisi Fard, Zhegang Ma, Sai Zhang
Nuclear Technology | Volume 209 | Number 11 | November 2023 | Pages 1680-1687
PSA 2021 Paper | doi.org/10.1080/00295450.2023.2234714
Articles are hosted by Taylor and Francis Online.
The U.S. Nuclear Regulatory Commission (NRC) and the nuclear power industry have evaluated and discussed various assumptions and methods for the treatment of potential common-cause failures (CCFs) in event and condition assessments (ECAs), specifically risk assessments performed as part of the NRC’s Significance Determination Process (SDP) in recent years. The basis for how a potential CCF is treated in SDP risk assessments is provided in NUREG-2225, “Basis for the Treatment of Potential Common-Cause Failure in the Significance Determination Process.” In light of new information and advancements in probabilistic risk assessment technology, the NRC and Idaho National Laboratory (INL) have continued the development of the causal alpha factor method (CAFM) for potential use in ECAs. The NRC and INL evaluated the suitability of using CAFM in SDP evaluations and reviewed the methodology to identify any potential data gaps.
Furthermore, an investigation was performed on the practice of common-cause component groups to determine if changes are needed to ensure that CCF is appropriately accounted for in the Standardized Plant Analysis Risk models. In addition, a focused review of the existing method that estimates CCF parameters was performed to determine if the assumptions used in the existing process result in CCF parameters that are representative of current industry performance. It was also desired to gather a better understanding of the aspects of the alpha factor method and data calculation process that either have significant effects on the CCF parameters and/or increase the uncertainties associated with these parameters. This paper provides a summary of recently completed work, including insights, conclusions, and recommendations from this effort.