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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.
M. M. R. Williams
Nuclear Science and Engineering | Volume 168 | Number 2 | June 2011 | Pages 138-150
Technical Paper | doi.org/10.13182/NSE11-45
Articles are hosted by Taylor and Francis Online.
The aqueous homogeneous reactor has assumed some importance in recent years as a potential medical isotopes production system. The kinetic behavior of such systems depends on the rate of generation of the radiolytic gas bubbles and the associated reactivity void coefficient. In this work we describe a method based on perturbation theory, and a simple description of bubble production, for deriving a value of the void coefficient of reactivity. It is shown that, in the small void fraction limit, the void coefficient is dependent only on the system properties and does not depend on power level or the bubble properties. Values are given for the void coefficient for a range of parameters assuming that the voids are distributed in three different ways, i.e., uniformly, proportional to power, and equal to the distribution due to buoyancy. The results are in reasonable agreement with values obtained by others, using more detailed methods, based on the reactors SILENE and MIPR.