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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The 2025 edition is a reinvigoration of the withdrawn ANS-54.8-1988 of the same title.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.
M. H. Kalos
Nuclear Science and Engineering | Volume 16 | Number 2 | June 1963 | Pages 227-234
Technical Paper | doi.org/10.13182/NSE63-A26504
Articles are hosted by Taylor and Francis Online.
It is proposed that importance sampling may be carried out using an approximate analytic form for the importance function. An altered Boltzmann kernel may then be computed. Choosing from this altered kernel is facilitated, in part, by particle splitting. The method is carried out in detail for neutron penetration in hydrogen slabs. Results are given for dose buildup and energy spectrum for slab depths up to 179 mean free paths for 8.1 Mev neutrons.
