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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.
Kiyoshi Takeuchi, Shun-ichi Tanaka
Nuclear Science and Engineering | Volume 90 | Number 2 | June 1985 | Pages 158-164
Technical Paper | doi.org/10.13182/NSE85-A17673
Articles are hosted by Taylor and Francis Online.
Gamma-ray exposure buildup factors are calculated using a discrete ordinates direct integration code, PALLAS-PL, SP-Br, for water, concrete, iron, and lead for point isotropic sources. These data include the effects of secondary photon sources arising from Compton scattering, bremsstrahlung, and annihilation. Comparisons of these results without bremsstrahlung to values obtained earlier by moments calculations show reasonable agreement, except in some instances of deep penetration. The calculated buildup factors are tabulated for incident energies of 0.1 to 15 MeV (except for lead, where the lower energy is 0.4 MeV) and for penetration depths as great as 40 mfp.