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Division Spotlight
Young Members Group
The Young Members Group works to encourage and enable all young professional members to be actively involved in the efforts and endeavors of the Society at all levels (Professional Divisions, ANS Governance, Local Sections, etc.) as they transition from the role of a student to the role of a professional. It sponsors non-technical workshops and meetings that provide professional development and networking opportunities for young professionals, collaborates with other Divisions and Groups in developing technical and non-technical content for topical and national meetings, encourages its members to participate in the activities of the Groups and Divisions that are closely related to their professional interests as well as in their local sections, introduces young members to the rules and governance structure of the Society, and nominates young professionals for awards and leadership opportunities available to members.
Meeting Spotlight
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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
TerraPower begins U.K. regulatory approval process
Seattle-based TerraPower signaled its interest this week in building its Natrium small modular reactor in the United Kingdom, the company announced.
TerraPower sent a letter to the U.K.’s Department for Energy Security and Net Zero, formally establishing its intention to enter the U.K. generic design assessment (GDA) process. This is TerraPower’s first step in deployment of its Natrium technology—a 345-MW sodium fast reactor coupled with a molten salt energy storage unit—on the international stage.
Hajime Kabashima, Fumio Kasahara
Nuclear Technology | Volume 205 | Number 5 | May 2019 | Pages 694-707
Technical Paper | doi.org/10.1080/00295450.2018.1518556
Articles are hosted by Taylor and Francis Online.
Large-scale electric discharges events called high energy arcing faults (HEAF) have been reported in a nonnegligible number at nuclear power stations (NPSs) worldwide. If a HEAF occurs, the pressure and temperature in the electrical equipment rise rapidly, causing an explosive phenomenon with destructive force that results in serious damage to the equipment. In addition, a HEAF may cause a fire, which would have a serious impact on cables and other components in and around the equipment with the potential to disrupt power, instruments, and control in the plant.
In order to investigate the HEAF progression and to understand well the phenomena involved, the Regulatory Standard and Research Department in the Secretariat of the Nuclear Regulation Authority conducted a series of experiments (HEAF tests). High-energy electric arcs were generated at the facility simulating the design and operating conditions of the medium-voltage metalclad switchgears (M/Cs) at Unit 1 of the Onagawa NPS where the fire subsequently spread to multiple M/Cs via cable duct due to HEAF.
The test data have been obtained for the M/Cs on the threshold values of the arc energy that results in ensuing fires and on the characteristics of high-energy arcs.
On the basis of the knowledge obtained by the test results, measures for prevention of ensuing fire and mitigation of explosion are proposed as a new requirement for fire protection regulation of Japanese NPSs. Amendments to the regulatory requirements were issued on August 8, 2017 and enforced on the same day.
This paper summarizes the information on the high-energy arc characteristics and arc energies resulting in ensuing fires that was used as the basis of the new requirements and discusses the trend of arc power.