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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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Deep Space: The new frontier of radiation controls
In commercial nuclear power, there has always been a deliberate tension between the regulator and the utility owner. The regulator fundamentally exists to protect the worker, and the utility, to make a profit. It is a win-win balance.
From the U.S. nuclear industry has emerged a brilliantly successful occupational nuclear safety record—largely the result of an ALARA (as low as reasonably achievable) process that has driven exposure rates down to what only a decade ago would have been considered unthinkable. In the U.S. nuclear industry, the system has accomplished an excellent, nearly seamless process that succeeds to the benefit of both employee and utility owner.
Rene Sanchez, David Loaiza, Glenn Brunson, Robert Kimpland
Nuclear Science and Engineering | Volume 147 | Number 3 | July 2004 | Pages 307-318
Technical Paper | doi.org/10.13182/NSE04-A2435
Articles are hosted by Taylor and Francis Online.
Scientists at the Los Alamos National Laboratory measured the critical masses of square prisms of highly enriched uranium diluted in various X/235U with matrix material and polyethylene. The configuration cores were 22.86 and 45.72 cm square and were reflected with 8.13-cm-thick and 10.16-cm-thick side polyethylene reflectors, respectively. The configurations had 10.16-cm-thick top and bottom polyethylene reflectors. For some configurations, the Rossi-, which is an eigenvalue characteristic for a particular configuration, was measured to establish a reactivity scale based on the degree of subcriticality. These experiments provided critical mass data in the thermal energy range for systems containing Si, Mg, Al, Gd, and Fe. The measured keff from these experiments was compared with the calculated keff from MCNP using ENDF/B-V and ENDF/B-VI cross-section data. The observed biases were +0.005 k and +0.008 k for Si, +0.0006 k and +0.008 k for Al, +0.0023 k for Mg, +0.004 k and +0.01304 k for Gd, and +0.0123 k and -0.00106 k for Fe.