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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.
Y. Harima, Y. Sakamoto, S. Tanaka, M. Kawai
Nuclear Science and Engineering | Volume 94 | Number 1 | September 1986 | Pages 24-35
Technical Paper | doi.org/10.13182/NSE86-A17113
Articles are hosted by Taylor and Francis Online.
A geometric-progression (G-P) method formula, Br = 1 + (B − 1) · (Kx − 1)/(K − 1), accurately represents the buildup factor data as a function of distance for the following reasons: 1. The value of parameter B corresponds to that of the buildup factor at 1 mfp, which is the integration of a basic spectrum for a specified material and for a specified source energy. 2. The variation of parameter K with penetration represents the photon dose multiplication and the change in the shape of the spectrum. Exposure buildup factors for point isotropic sources in an infinite medium approximated by the G-P fitting parameters are in good agreement with the basic data calculated by the PALLAS code, including that of boron for low energies, and of lead, including the effects of bremsstrahlung and fluorescence. The validity of using the G-P parameters to interpolate the buildup factor in μr and in E is ascertained. Furthermore, the extrapolation to the buildup data for depths above 40 mfp is examined.
