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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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.
H. Hirayama, D. K. Trubey
Nuclear Science and Engineering | Volume 99 | Number 2 | June 1988 | Pages 145-156
Technical Paper | doi.org/10.13182/NSE88-A23555
Articles are hosted by Taylor and Francis Online.
The effects of including incoherent and coherent scattering in a calculation of the exposure buildup factors for plane normal gamma-ray sources have been investigated by using an electron-gamma-ray shower Monte Carlo code, EGS4, for water, iron, and lead in the 40- to 200-keV range. The “true” buildup factors and “pseudo” buildup factors for practical uses are defined to clarify the effects of bound-electron Compton (incoherent) and coherent scattering and are tabulated for penetration depths up to 10 mfp. The pseudo buildup factor increases by including incoherent scattering and decreases by including coherent scattering. The degree of each effect varies with the atomic number of the material. The effect of incoherent scattering is large for materials of small atomic number, and the effect of coherent scattering is large for materials of large atomic number.