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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The 2025 edition is a reinvigoration of the withdrawn ANS-54.8-1988 of the same title.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.
E. A. Mason, J. A. Larrimore
Nuclear Science and Engineering | Volume 9 | Number 3 | March 1961 | Pages 332-340
Technical Paper | doi.org/10.13182/NSE61-A25884
Articles are hosted by Taylor and Francis Online.
In reactors fueled with thorium, increasing specific power leads to reduction of fuel reactivity lifetime and conversion ratio because of the appreciable decay time and neutron absorption cross section of Pa233. A generalized study of these effects in thorium-U233 fueled reactors has been carried out using a simplified reactor model. It was found that the most important specific power effect on fuel reactivity is the holdup of Pa233, rather than its burnout to U234. Using conventional cost bases, the effect of specific power on the fuel costs for thorium fueled reactors has been shown to be small in the range of practical specific powers.
