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Conference Spotlight
2026 Nuclear Energy Conference & Expo (NECX)
August 24–27, 2026
Dallas, TX|Hilton Anatole
Latest Magazine Issues
Jul 2026
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2026
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Nuclear Science and Engineering
September 2026
Nuclear Technology
August 2026
Fusion Science and Technology
Latest News
The human factor in licensing and operating the next generation of nuclear plants
As human factors specialists working at the intersection of human performance and nuclear operations, we are witnessing one of the nuclear sector’s most significant transitions in decades. The emergence of small modular reactors, microreactors, and other advanced designs is reshaping the industry’s landscape. Digital instrumentation and controls, passive safety systems, and increased automation are creating opportunities for greater safety margins and more flexible operation. These same features also fundamentally redefine what it means to “operate” a nuclear plant. Interactions among human roles, automation, and passive systems shape how people maintain awareness, exercise judgment, and intervene when necessary. These developments affect both operational realities and the regulatory foundations on which nuclear safety is built.
Nuclear Criticality Safety Division 2025 Conference
Japan Atomic Energy Agency (JAEA)
Group Leader in the Criticality Safety Research Group of the Nuclear Safety Research Center
Dr. Satoshi Gunji completed his PhD in Engineering at Tohoku University before joining the Power and Industrial Systems Research and Development Center of Toshiba Corporation in 2007 as a researcher in the Nuclear Reactor System Analysis Group. Before the accident at the Tokyo Electric Power Company's Fukushima Daiichi Nuclear Power Plant, his main work was on criticality safety of next-generation light water reactor fuel. He was also an experimenter and an operator of the Toshiba Nuclear Critical Assembly.
After Toshiba decided to decommission the NCA, he moved to the Criticality Safety Research Group at the Japan Atomic Energy Agency (JAEA), where he currently works. At the time, JAEA was proceeding with plans to modify the criticality assembly STACY to conduct criticality assessments of the fuel debris generated by the FDNPP accident. He participated in this project as a criticality safety expert and planned the criticality experiment plans. STACY achieved first criticality in 2024, and he has been directing subsequent experiments.
Last modified August 26, 2025, 10:54am CDT
