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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.
John MacPhee
Nuclear Science and Engineering | Volume 7 | Number 1 | January 1960 | Pages 33-43
Technical Paper | doi.org/10.13182/NSE60-A25695
Articles are hosted by Taylor and Francis Online.
Approximate methods, which are simple and quick to use, are presented for finding the response of a critical and a subcritical reactor, to ramp inputs of δk. The solutions are based on one equivalent group of delayed neutrons. Various methods of selecting the equivalent delayed neutron decay constant are discussed and it is shown that a one-group model will always be conservative if a particular method of selection is used. It is also demonstrated, that the approximate solutions are more accurate than the well-known approximation proposed by Newson.
