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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.
G. C. Pomraning
Nuclear Science and Engineering | Volume 69 | Number 1 | January 1979 | Pages 6-13
Technical Paper | doi.org/10.13182/NSE79-A21279
Articles are hosted by Taylor and Francis Online.
Analytic estimates are given for the angular dependence of the neutron (or photon) flux in toroidal geometry arising from the toroidal character of the configuration. The model used in the analysis is the one-group homogeneous diffusion model The toroidal angular effects in the local flux are shown to be first order in ϵ, the inverse aspect ratio, whereas angular effects occurring in spatial integrals of the flux are found to be of order ϵ2. An analytic expression for the Green's function for diffusion equation in toroidal geometry is given correct to order ϵ2, and typical numerical results are shown. A transformation of the scalar flux is presented that removes all angular dependence from the streaming term in the diffusion equation and removes the angular dependence from the absorption term correct to order ϵ. The overall conclusion reached is that angular toroidal effects are not simply characterized.
