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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.
F. Schroeder, S. G. Forbes, W. E. Nyer, F. L. Bentzen, G. O. Bright
Nuclear Science and Engineering | Volume 2 | Number 1 | February 1957 | Pages 96-115
doi.org/10.13182/NSE57-A15576
Articles are hosted by Taylor and Francis Online.
As a part of a program of reactor safety investigations, the response of a heterogeneous, water-moderated and -reflected reactor (SPERT I) to instantaneous reactivity additions has been studied experimentally with initial temperature of 20°C and initial power level of 5 watts. Excess reactivity additions from approximately O.3% to 1.4%, which result in asymptotic reactor periods from 10 sec to 7 msec, produced self-limiting power bursts with peaks up to 1300 Mw. Plots of the typical behavior of reactor power, fuel plate temperatures, and transient pressures for these tests are presented and discussed. Maximum reactor power, fuel plate temperature, pressure, energy release, and other quantities are correlated as functions of reactor period. The instantaneous excess reactivity of the system during the transient test has been computed from the experimental power behavior and typical results are shown. The reactivity compensation necessary to limit a power burst of this type has been determined and is discussed as a function of initial reactor period. Several mechanisms for the self-shutdown of the reactor are postulated and discussed in light of the experimental results.
