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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The 2025 edition is a reinvigoration of the withdrawn ANS-54.8-1988 of the same title.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.
P. Vértes
Nuclear Science and Engineering | Volume 16 | Number 4 | August 1963 | Pages 363-368
Technical Paper | doi.org/10.13182/NSE63-A26546
Articles are hosted by Taylor and Francis Online.
Some problems of the theoretical interpretation of pulsed neutron experiments are investigated in this paper, on the basis of the energy dependent Boltzmann equation. The relation of the infinite medium theory to the finite medium experiments is discussed in details. We perform a calculation in P1L1 approximation in order to determine the form of neutron flux and the extrapolation length. It is demonstrated that the existence of an asymptotic region is not required to apply the infinite medium theory to the finite medium experiments.
