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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.
N. J. Peters, K. Kutikkad
Nuclear Technology | Volume 201 | Number 1 | January 2018 | Pages 80-98
Technical Paper | doi.org/10.1080/00295450.2017.1398582
Articles are hosted by Taylor and Francis Online.
The details of robust computational and novel semiempirical methodologies that were developed and tested at the University of Missouri Research Reactor (MURR) to accurately determine the possibility of a “hot” startup and the estimated critical position (ECP) of the control rods following an unplanned shutdown are presented. The computations, based on a modified coupled MCNP5-ORIGEN2 code system and using ENDF/B-VII.0 and TENDL-2013 nuclear data sets, accurately simulate the MURR core operational histories while predicting the critical rod positions within ±0.001 Δk/k of experimental critical data. In this study, using the coupled MCNP5-ORIGEN2 computations, various core-specific parameters were methodically characterized and were adapted into a semiempirical formulation better suited for practical reactor operations. The predictive capabilities of these novel semiempirical approaches regarding core criticality and ECPs required utilizing, for the first time, the net transient response of the negative reactivity worth for necessary fission product poisons including 135mXe and several others. Calculation-to-experiment deviations in hot-startup criticals and the corresponding control rod positions are shown to be less than ±0.03% Δk/k and ±1% difference in relative rod position, respectively.
