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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.
G. S. Sidhu, W. E. Farley, L. F. Hansen, T. Komoto, B. Pohl, C. Wong
Nuclear Science and Engineering | Volume 63 | Number 1 | May 1977 | Pages 48-54
Technical Paper | doi.org/10.13182/NSE77-A27003
Articles are hosted by Taylor and Francis Online.
We have measured the spectra of neutrons and secondary gamma rays emerging from a liquid-nitrogen sphere of 129.3-cm radius with a 14-MeV neutron source at its center. Time-of-flight techniques were used to obtain the detailed data and to minimize background. To compare the measurements with calculations, we folded the detector efficiencies and appropriate experimental parameters into the calculated output of TARTNP, a coupled neutron-photon Monte Carlo transport code utilizing the Lawrence Livermore Laboratory Evaluated Neutron Data Library, September 1975. The calculated neutron spectra show fair agreement with the measurements, and the calculated gamma-ray spectrum is nearly the same as the corresponding measured spectrum. The total biological dose derived from these measurements is in good agreement with the calculations and provides a benchmark for a dose-versus-range curve obtained by TARTNP calculations.