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NRC proposes changes to its rules on nuclear materials
In response to Executive Order 14300, “Ordering the Reform of the Nuclear Regulatory Commission,” the NRC is proposing sweeping changes to its rules governing the use of nuclear materials that are widely used in industry, medicine, and research. The changes would amend NRC regulations for the licensing of nuclear byproduct material, some source material, and some special nuclear material.
As published in the May 18 Federal Register, the NRC is seeking public comment on this proposed rule and draft interim guidance until July 2.
C. M. Eisenhauer, G. L. Simmons
Nuclear Science and Engineering | Volume 56 | Number 3 | March 1975 | Pages 263-270
Technical Paper | doi.org/10.13182/NSE75-A26739
Articles are hosted by Taylor and Francis Online.
Gamma-ray buildup factors in ordinary concrete have been calculated by the moments method. Results for concrete kerma and air kerma are tabulated for source energies from 15 MeV to 15 keV. Parameters are given that allow calculation of the buildup factor by means of a simple analytic expression. Comparisons are made with earlier calculations, and the effects of annihilation radiation are discussed.
