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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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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A new ANSI/ANS standard for liquid metal fire protection published
ANSI/ANS-54.8-2025, Liquid Metal Fire Protection in LMR Plants, received approval from the American National Standards Institute on September 2 and is now available for purchase.
The 2025 edition is a reinvigoration of the withdrawn ANS-54.8-1988 of the same title. The Advanced Reactor Codes and Standards Collaborative (ARCSC) identified the need for a current version of the standard via an industry survey.
Typical liquid metal reactor designs use liquid sodium as the coolant for both the primary and intermediate heat-transport systems. In addition, liquid sodium and NaK (a mixture of sodium and potassium that is liquid at room temperature) are often used in auxiliary heat-removal systems. Since these liquid metals can react readily with oxygen, water, and other compounds, special precautions must be taken in the design, construction, testing, and maintenance of the sodium/NaK systems to ensure that the potential for leakage is very small.
Edward Garelis, John L. Russell, Jr.
Nuclear Science and Engineering | Volume 16 | Number 3 | July 1963 | Pages 263-270
Technical Paper | doi.org/10.13182/NSE63-A26529
Articles are hosted by Taylor and Francis Online.
A new method of utilizing pulsed neutron source measurements for the determination of the subcriticality of an assembly directly in terms of dollars is proposed. Essentially, the method determines the parameter (kβ/l) using the complete response curve of a repetitively pulsed assembly after the quasi-equilibrium state has been attained. This value of (kβ/l) coupled with the usual α-measurement, assuming the prompt decay constant to be dominant, yields the reactivity directly. The analytical model is based on a bare one-group diffusion theory system with m-delayed precursors. The application of these results to experiment shows that their applicability is much broader than the simple analytical model would indicate.