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2026 Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
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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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Nuclear power’s new rule book: Managing uncertainty in efficiency, safety, and independence
The U.S. nuclear industry is standing at its most volatile regulatory moment yet—one that will shape the trajectory and the safety of the industry for decades to come. Recent judicial, legislative, and executive actions are rewriting the rules governing the licensing and regulation of nuclear power reactors. Although these changes are intended to promote and accelerate the deployment of new nuclear energy technologies, the collision of multiple legal shifts—occurring simultaneously and intersecting with profound technological uncertainties—is overwhelming the Nuclear Regulatory Commission and threatening to destabilize investor and industry expectations.
L. Bosland, G. Weber, W. Klein-Hessling, N. Girault, B. Clement
Nuclear Technology | Volume 177 | Number 1 | January 2012 | Pages 36-62
Technical Paper | Reactor Safety | doi.org/10.13182/NT12-A13326
Articles are hosted by Taylor and Francis Online.
The Institut de Radioprotection et de Sûreté Nucléaire (IRSN), France, and the Gesellschaft für Anlagen- und Reaktorsicherheit (GRS), Germany, have been involved in the analyses and modeling of PHEBUS tests and particularly in iodine chemistry behavior in the containment. To analyze the accuracy of the chemistry models developed and reproduce volatile iodine formation, iodine behavior in PHEBUS FPT-1 containment was modeled by both IRSN and GRS with two different codes: ASTEC and COSOSYS. The ways of modeling (using the ASTEC/IODE and COCOSYS/AIM respective modules) and the nodalization of both approaches are presented and compared, as well as the assumptions made to perform the calculations. The results of the comprehensive analyses are compared with the experimental results, and interpretation of the iodine behavior in the PHEBUS FPT-1 containment is given. Then, a common point of view is concluded that highlights the lack of knowledge for some phenomena of significant impact on the iodine behavior in the containment during a severe accident. Organic iodide and iodine oxide formation models in particular are pointed out for the gaseous phase. The need for improving iodine behavior models including their coupling to thermal hydraulics and aerosol physics is also explained.
