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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.
James W. Wade
Nuclear Science and Engineering | Volume 4 | Number 1 | July 1958 | Pages 12-24
Technical Paper | doi.org/10.13182/NSE58-A25516
Articles are hosted by Taylor and Francis Online.
The neutron age for fission neutrons and Po-Be neutrons was measured in mixtures of D2O and H2O. The age was evaluated from the second moment of the slowing-down distribution at the 1.4-ev resonance of indium. The ages of fission neutrons at concentrations of 99.8, 99.0, 98.4, 95.3, 94.0, 91.8, 48.6% D2O, and in pure H2O were 109, 107, 106, 93, 86, 78, 38.6, and 31 cm2, respectively. In the range from 100 to 90% D2O, the rate of decrease of the age was approximately 4 cm2 for each additional per cent of H2O. The ages of Po-Be neutrons in 99.4, 48.6% D2O, and in H2O were 148, 72.5, and 55.7 cm2, respectively.