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Conference Spotlight
2026 Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
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
Seconds Matter: Rethinking Nuclear Facility Security for the Modern Threat Landscape
In today’s rapidly evolving threat environment, nuclear facilities must prioritize speed and precision in their security responses—because in critical moments, every second counts. An early warning system serves as a vital layer of defense, enabling real-time detection of potential intrusions or anomalies before they escalate into full-blown incidents. By providing immediate alerts and actionable intelligence, these systems empower security personnel to respond decisively, minimizing risk to infrastructure, personnel, and the public. The ability to anticipate and intercept threats at the earliest possible stage not only enhances operational resilience but also reinforces public trust in the safety of nuclear operations. Investing in such proactive technologies is no longer optional—it’s essential for modern nuclear security.
Tyler Sumner, Anton Moisseytsev, Daniel O’Grady, Lander Ibarra, Christopher Keckler, Justin Thomas, Thomas Fanning, Carlo Parisi, Nolan Anderson, Frederick Gleicher, SuJong Yoon
Nuclear Science and Engineering | Volume 196 | Number 1 | October 2022 | Pages S289-S308
Technical Paper | doi.org/10.1080/00295639.2022.2053487
Articles are hosted by Taylor and Francis Online.
The Versatile Test Reactor (VTR) is a fast spectrum test reactor currently being developed in the United States under the direction of the U.S. Department of Energy, Office of Nuclear Energy. Safety analysis of the conceptual VTR design is being performed using the SAS4A/SASSYS-1 fast reactor safety analysis code with a model representing the reactor core, primary and secondary heat transport systems, reactor vessel auxiliary cooling system, and reactor protection system. The system’s response and safety performance are being evaluated for a wide spectrum of event initiators and accident sequences. This paper presents an overview of the activities that are ongoing in support of the modeling and analysis of safety basis events (SBEs) in the VTR, including the VTR SAS4A/SASSYS-1 model development, an overview of the SAS4A/SASSYS-1 verification and validation efforts, and a summary of key model development activities to improve the predictive capability of the code. A summary of the results and an analysis of several key SBEs are also presented. VTR authorization from the U.S. Department of Energy will require transient simulations that are demonstrated to be accurate.
