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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.
Yoshiko Harima, Yukio Sakamoto, Naohiro Kurosawa, Akinao Shimizu
Nuclear Technology | Volume 168 | Number 3 | December 2009 | Pages 861-866
Shielding | Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (PART 3) / Radiation Protection | doi.org/10.13182/NT09-A9319
Articles are hosted by Taylor and Francis Online.
The geometric-progression (G-P) formula can accurately reproduce buildup factor data up to depths of 40 mean free paths (mfp) within a few percent. This formula was improved to apply to depths up to 100 mfp, using the buildup factor data of Shimizu et al. (2004) calculated with the Invariant Embedding method.The behavior of the K parameter as a function of distance was examined, and a new formula was introduced from the depth of Xm ([approximately]40 mfp). The fitting parameters were determined using a minimizing procedure of the maximum fractional deviation (MMD). Within some sets of parameters determined by the MMD fit, one set of parameters was selected that realized the interpolation of the buildup factor with regard to energy, using interpolated G-P parameters. Consequently, discrete buildup factor data were converted to continuous data with regard to both energy and distance.
