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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.
Donald C. Coonfield, Grover Tuck, Harold E. Clark, Bruce B. Ernst
Nuclear Science and Engineering | Volume 39 | Number 3 | March 1970 | Pages 320-328
Technical Paper | doi.org/10.13182/NSE70-A19993
Articles are hosted by Taylor and Francis Online.
Critical masses have been determined by experiment and by calculation for enriched-uranium-metal spherical shells moderated internally with a sphere of mild steel of radius 8.01 cm. The shells were reflected with various thicknesses of mild steel followed by an effectively infinite amount of oil. The points representing critical mass as a function of the thickness of the steel reflector are not related by a smooth curve. The irregularity appears to be most severe for a 3-cm-thick steel reflector and is due to the resonance in the neutron elastic-scattering cross section of iron.
