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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.
Shun-ichi Tanaka, Kiyoshi Takeuchi
Nuclear Science and Engineering | Volume 93 | Number 4 | August 1986 | Pages 376-385
Technical Paper | doi.org/10.13182/NSE86-A18473
Articles are hosted by Taylor and Francis Online.
Detailed calculations of the buildup factors and spectra of gamma rays including fluorescence radiations in lead are carried out using a discrete ordinates code, PALLAS-PL,SP-Br. The exposure and absorbed dose buildup factors with and without fluorescence are tabulated for 11 source energies from 0.09 to 0.3 MeV for penetration depths up to 40 mfp. Important characteristics of the gamma-ray transport in the vicinity of the K edge of lead are explored using detailed energy spectra in the medium. The contribution of the fluorescence to buildup factors is extremely significant for the sources close to the K edge energy.
