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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.
T. F. Wimett, H. C. Paxton
Nuclear Science and Engineering | Volume 78 | Number 4 | August 1981 | Pages 425-431
Technical Note | doi.org/10.13182/NSE81-A21379
Articles are hosted by Taylor and Francis Online.
A critical assembly with circulating enriched uranium solution was operated for brief periods at power up to 2 MW corresponding to a core temperature differential of 13°C. Although delayed neutron precursors were swept out of the critical region, contributing little to control, power followed excess reactivity satisfactorily. At excess reactivity of 0.2 dollar, power oscillations began to appear, and above ∼0.5 dollar they diverged. The 1-s period appears to be associated with vibration of unconstrained piping. Reactivity quench coefficients are greater than those measured without flow. The difference is attributed to macroscopic release of radiolytic gas.
