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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.
H. W. Lewis
Nuclear Science and Engineering | Volume 98 | Number 1 | January 1988 | Pages 79-81
Technical Paper | doi.org/10.13182/NSE88-A23527
Articles are hosted by Taylor and Francis Online.
A Bayesian analysis is made of the probability of core melt (defined as “core on the floor”) for U.S. reactors, using methods that are an extension of those used in an earlier work, and that can therefore be used to answer different questions. The essential new point is that at any time the estimate of the probability of core melt varies continuously as melt-free experience accumulates, with a substantial effect on the estimates. The most interesting result is that the probability of no-melt-yet stays large somewhat longer than one might have guessed, largely because melt-free experience feeds on itself in reducing the probability of subsequent core melt, and this process continues until the first melt.