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Nuclear Criticality Safety
NCSD provides communication among nuclear criticality safety professionals through the development of standards, the evolution of training methods and materials, the presentation of technical data and procedures, and the creation of specialty publications. In these ways, the division furthers the exchange of technical information on nuclear criticality safety with the ultimate goal of promoting the safe handling of fissionable materials outside reactors.
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2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott Downtown
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Former NRC commissioners lend support to efforts to eliminate mandatory hearings
A group of nine former nuclear regulatory commissioners sent a letter Wednesday to the current Nuclear Regulatory Commission members lending support to efforts to get rid of mandatory hearings in the licensing process, which should speed up the process by three to six months and save millions of dollars.
J. S. Eakins
Nuclear Technology | Volume 168 | Number 3 | December 2009 | Pages 894-898
Shielding | Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (PART 3) / Radiation Protection | doi.org/10.13182/NT09-A9324
Articles are hosted by Taylor and Francis Online.
The transmission of 0.511-MeV photons through concrete, lead, or iron is determined using MCNP4c2, by exposing 50-cm-radius cylinders of the materials to plane parallel sources. Cylinders are modeled with thicknesses up to 50 cm in 5-cm increments for concrete, 10 cm in 1-cm increments for lead, and 20 cm in 2-cm increments for iron. The resulting transmission factors span from 1 to <10-3 for concrete, to almost 10-7 for lead, and to roughly 10-5 for iron. The reliability of the method is checked by performing the calculations for selected thicknesses of material with a 0.662-MeV source and comparing the results against published data. Acceptable agreement is reported in almost all cases.
