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Division Spotlight
Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
Meeting Spotlight
2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott Downtown
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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Latest News
Countering the nuclear workforce shortage narrative
James Chamberlain, director of the Nuclear, Utilities, and Energy Sector at Rullion, has declared that the nuclear industry will not have workforce challenges going forward. “It’s time to challenge the scarcity narrative,” he wrote in a recent online article. “Nuclear isn't short of talent; it’s short of imagination in how it attracts, trains, and supports the workforce of the future.”
George C. Wu, Lawrence Ruby
Nuclear Science and Engineering | Volume 68 | Number 3 | December 1978 | Pages 349-351
Technical Note | doi.org/10.13182/NSE78-A27311
Articles are hosted by Taylor and Francis Online.
Three-group diffusion theory has been applied to a computation of the 231Pa mass required to sustain a fast-neutron chain reaction. The method was tested by preliminary calculation of several 235U-238U systems and of a single 239Pu-240Pu system. The best agreement between predictions and measurements was found for high-enrichment 235U-238U systems. In the case of 231Pa, where many of the necessary data do not exist, use was made of the characteristics of 237Np as a substitute. The predicted critical radius for 231Pa is 22.67 ± 1.81 cm, and the corresponding critical mass is 750 ± 180 kg.
