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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
Standards Program
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The 2025 edition is a reinvigoration of the withdrawn ANS-54.8-1988 of the same title.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.
G. J. Safford, W. W. Havens, Jr.
Nuclear Science and Engineering | Volume 11 | Number 1 | September 1961 | Pages 65-68
Technical Paper | doi.org/10.13182/NSE61-A25986
Articles are hosted by Taylor and Francis Online.
The total neutron cross section of Pu239 has been measured at seventeen neutron energies between 0.00291 ev and 0.10 ev with a crystal spectrometer. The absorption cross section was obtained by subtracting the relatively small scattering cross section from the measured total cross section. The sample used was a plutonium-aluminum metallic foil containing 1% aluminum. The isotopic content of the plutonium was 99.82% Pu239, 0.15% Pu240, and 0.03% Pu241. The value obtained for the absorption cross section of Pu239 at 2200 meters/sec was σa = 1007 ± 8 barns.
