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Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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.
Takaaki Mochida, Mitsunari Nakamura, Jun-Ichi Yamashita, Hiromi Maruyama, Sakae Muto, Shigeru Kasai
Nuclear Technology | Volume 114 | Number 3 | June 1996 | Pages 308-317
Technical Paper | Nuclear Fuel Cycle | doi.org/10.13182/NT96-A35235
Articles are hosted by Taylor and Francis Online.
The multienrichment boiling water reactor (BWR) initial core design was first applied to the Kashiwazaki-Kariwa Nuclear Power Station Unit 5 [1100-MW(electric) BWR] in Japan. This core is designed to improve fuel discharge exposure, capacity factors, and operability. The design study shows that three types of fuel bundles with different enrichments are suitable to achieve the design targets. Three bundle enrichments are selected to simulate each of the following: fresh bundles, once-burned bundles, and twice-burned bundles in the reload core. Although the heterogeneity of multienrichment design increases the complexity of the design analysis, both the initial criticality test and the moderator temperature coefficient measurement showed good agreement with our prediction. Subsequent full-power operation verified the expected core performance. Average discharge exposure for the total initial fuel is ∼10% larger than that for the conventional single-enrichment BWR initial fuel with reinsertion of discharged fuel at the end of the first cycle. These experiences verified the effectiveness of a multienrichment initial core for the improvement of fuel utilization, capacity factors, and operability