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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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The RAIN scale: A good intention that falls short
Radiation protection specialists agree that clear communication of radiation risks remains a vexing challenge that cannot be solved solely by finding new ways to convey technical information.
Earlier this year, an article in Nuclear News described a new radiation risk communication tool, known as the Radiation Index, or, RAIN (“Let it RAIN: A new approach to radiation communication,” NN, Jan. 2025, p. 36). The authors of the article created the RAIN scale to improve radiation risk communication to the general public who are not well-versed in important aspects of radiation exposures, including radiation dose quantities, units, and values; associated health consequences; and the benefits derived from radiation exposures.
Jay E. Boudreau, R. C. Erdmann
Nuclear Science and Engineering | Volume 51 | Number 2 | June 1973 | Pages 206-222
Technical Paper | doi.org/10.13182/NSE73-A26595
Articles are hosted by Taylor and Francis Online.
Secondary criticality resulting from massive core rearrangement is discussed where the material dynamics results from either mild or strong initial excursions. Diffusion theory is used to study the effect of moving boundaries on the flux, and to study the effect of internal fuel rearrangement on keff. Numerical transport methods are used to make accurate determinations of keff for complicated fuel configurations arising from disassembly calculations. It is concluded that secondary criticality may occur from fuel rearrangement, but that it is unlikely in most cases. Variations in core height/diameter ratio, zonal enrichment, and overall size can change the tendency for autocatalysis significantly.