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Nuclear Nonproliferation Policy
The mission of the Nuclear Nonproliferation Policy Division (NNPD) is to promote the peaceful use of nuclear technology while simultaneously preventing the diversion and misuse of nuclear material and technology through appropriate safeguards and security, and promotion of nuclear nonproliferation policies. To achieve this mission, the objectives of the NNPD are to: Promote policy that discourages the proliferation of nuclear technology and material to inappropriate entities. Provide information to ANS members, the technical community at large, opinion leaders, and decision makers to improve their understanding of nuclear nonproliferation issues. Become a recognized technical resource on nuclear nonproliferation, safeguards, and security issues. Serve as the integration and coordination body for nuclear nonproliferation activities for the ANS. Work cooperatively with other ANS divisions to achieve these objective nonproliferation policies.
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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
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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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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.
Florin Curca-Tivig
Nuclear Technology | Volume 124 | Number 1 | October 1998 | Pages 65-81
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT98-A2909
Articles are hosted by Taylor and Francis Online.
The European Pressurized Water Reactor's (EPR's) safety injection system (SIS) comprises four trains, each of them consisting of a medium head safety injection, an accumulator, and a low head safety injection (LHSI). Injection mode is into the cold legs of the main coolant line for the short term. This emergency core cooling (ECC) mode is quite different from the typical German concept with combined injection, i.e., safety injection into both the cold and the hot legs of the main coolant line at least for accumulator and LHSI. Therefore, the German Safety Authority requested justification for giving up the ECC-mode used in German pressurized water reactors, the so-called "combined injection." Furthermore, the Reaktor-sicherheitskommission requested a comparison between cold-leg injection and combined injection in terms of ECC efficiency over all relevant accident sequences.The evolution from combined injection to cold-leg injection is described and results of comparative analysis are summarized. It is demonstrated that EPR's SIS is a well-balanced system, which ensures high ECC efficiency and limits loads to containment over the whole accident spectrum. For the entire loss-of-coolant accident (LOCA) spectrum, ECC efficiency of EPR's SIS is practically equivalent to ECC efficiency of a SIS of the KONVOI type with combined injection. The smaller the break, the more insignificant are differences. The ECC mode has a negligible impact on containment pressure and temperature evolution during a LOCA. Neither with combined injection nor with cold-leg injection is a containment spray system needed.
