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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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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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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“The time is now” to advance U.S. nuclear—Part 1
The Nuclear Regulatory Commission is gearing up to tackle an influx of licensing requests and oversight of advanced nuclear reactor technology, especially small modular reactors.
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.
