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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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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.
C. B. Mills
Nuclear Science and Engineering | Volume 13 | Number 4 | August 1962 | Pages 301-305
Technical Paper | doi.org/10.13182/NSE62-A26172
Articles are hosted by Taylor and Francis Online.
The complete spatial separation of moderator and uranium fuel bearing regions are shown by experiment to result in critical reactors with low critical mass and relatively uniform fissioning density. Studies of several of these experiments to establish the accuracy of a numerical method of calculation (SNG) for this class of problems show good correspondence between theory and experiment. This method is then used for a useful survey of critical mass and U235 atomic density as a function of geometry for the best moderators, D2O and Be.