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NRC introduces microreactor regulatory framework
The Nuclear Regulatory Commission has released a new licensing framework for microreactors and similar reactor designs that may provide a more suitable pathway for applicants with simpler technologies.
The proposed rule—known as Part 57—is the latest to come out of the NRC’s rules review and overhaul stemming from the ADVANCE Act and 2025 nuclear-related executive orders. It is also the latest framework developed for advanced reactor designs shifting away from light water reactor technology, such as the Part 53 rule finalized in March.
C. J. Orth
Nuclear Science and Engineering | Volume 43 | Number 1 | January 1971 | Pages 54-57
Technical Paper | doi.org/10.13182/NSE71-A21245
Articles are hosted by Taylor and Francis Online.
The values of the average number of prompt neutrons emitted in the spontaneous fission of some recently available even-even heavy nuclides have been determined by separately counting neutrons and spontaneous fissions and comparing these counts with similar counts from 252Cf standards. The results are as follows: 244Pu , 248Cm , 250Cm , 250Cf , 254Cf , all on the basis of for 252Cf. A comparison of these results with existing data for other heavy nuclides indicates that is both Z and A dependent in a manner similar to that calculated by Bondarenko et al.
