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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 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 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.
R. Chawla
Nuclear Technology | Volume 52 | Number 2 | February 1981 | Pages 306-309
Technical Note | Fission Reactor | doi.org/10.13182/NT81-A32673
Articles are hosted by Taylor and Francis Online.
The minimum overall size of a reflected pebble-bed reactor is, in general, considerably smaller than that of the corresponding bare-critical assembly. For a reactor fueled with low-enriched uranium fuel elements at average burnup, the minimum outer radius for the reflected system was found to be up to 20% smaller than the bare-critical radius. The fact that the graphite reflector can effectively be so much“more reactive” than core material in the outer regions of such a reactor is shown to be largely a consequence of the relatively high degree of voidage (∼40%) inherent in pebble-bed cores.