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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.
James T. Cronin, Kord S. Smith
Nuclear Technology | Volume 100 | Number 2 | November 1992 | Pages 174-183
Technical Paper | Nuclear Reactor Safety | doi.org/10.13182/NT92-A34740
Articles are hosted by Taylor and Francis Online.
A methodology for homogenization and functionalization of one-dimensional cross sections for RETRAN has been developed and encoded into the SIMULATES and SLICK computer programs. The method relies on the SIMULATE-3 nodal reactor analysis code to provide accurate solutions of the three-dimensional neutron diffusion equation in two energy groups. The process of producing the required data involves two distinct problems: (a) the spatial homogenization of the three-dimensional cross sections and diffusion coefficients into one-dimensional variables and (b) the functionalization of the one-dimensional data in terms of the feedback variables of coolant density, fuel temperature, and control fraction. The homogenization method is based on equivalence theory and preserves the eigenvalue and one-dimensional planar reaction rates of the three-dimensional solution. The functionalization of the homogenized cross sections is accomplished by performing analogous one-dimensional state calculations with the RETRAN thermal-hydraulic models and then fitting to the RETRAN feedback variables. The methodology has been verified by comparing the results of one-dimensional calculations performed with the one-dimensional cross sections to three-dimensional calculations. Close agreement between the one- and three-dimensional results has been demonstrated.