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Human Factors, Instrumentation & Controls
Improving task performance, system reliability, system and personnel safety, efficiency, and effectiveness are the division's main objectives. Its major areas of interest include task design, procedures, training, instrument and control layout and placement, stress control, anthropometrics, psychological input, and motivation.
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2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott Downtown
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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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High-temperature plumbing and advanced reactors
The use of nuclear fission power and its role in impacting climate change is hotly debated. Fission advocates argue that short-term solutions would involve the rapid deployment of Gen III+ nuclear reactors, like Vogtle-3 and -4, while long-term climate change impact would rely on the creation and implementation of Gen IV reactors, “inherently safe” reactors that use passive laws of physics and chemistry rather than active controls such as valves and pumps to operate safely. While Gen IV reactors vary in many ways, one thing unites nearly all of them: the use of exotic, high-temperature coolants. These fluids, like molten salts and liquid metals, can enable reactor engineers to design much safer nuclear reactors—ultimately because the boiling point of each fluid is extremely high. Fluids that remain liquid over large temperature ranges can provide good heat transfer through many demanding conditions, all with minimal pressurization. Although the most apparent use for these fluids is advanced fission power, they have the potential to be applied to other power generation sources such as fusion, thermal storage, solar, or high-temperature process heat.1–3
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.