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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.
Raymond Gold and Roland J. Armani, James H. Roberts
Nuclear Science and Engineering | Volume 34 | Number 1 | October 1968 | Pages 13-32
Technical Paper | doi.org/10.13182/NSE68-A19362
Articles are hosted by Taylor and Francis Online.
The method of fission track counting has been placed on a precise absolute basis. Sources of systematic error have been investigated and eliminated or reduced so that precise fission rate measurements can be conducted. Solid State Track Recorders (SSTR) of pre-etched mica and polycarbonate resin (Makrofol) have been used. Experimental results depend critically on the quality of the fission sources employed. Consequently, different methods of fission source preparation have been examined. The efficiency and sensitivity of this method have been determined for both mica and Makrofol. An irradiation assembly providing uniform neutron flux exposures is used for relative measurements. Absolute calibrations have been carried out with 244Cm spontaneous fission sources. A limiting accuracy of close to 1% for absolute uranium fission rate measurements has been achieved.