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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.
J. Stepanek , M. Segev
Nuclear Science and Engineering | Volume 108 | Number 3 | July 1991 | Pages 215-229
Technical Paper | doi.org/10.13182/NSE91-A23820
Articles are hosted by Taylor and Francis Online.
A surface current methodology is developed to respond to the need for treating the various levels of material heterogeneity in a double-heterogeneous multilayer multicell in processing neutron multigroup cross sections in the resonance as well as in the thermal energy range. First, the basic surface cosine current transport equations to calculate the energy-dependent neutron flux spatial distribution in the multilayered multicell are formulated. Slab, spherical, and cylindrical geometries, as well as square and hexagonal lattices and pebble-bed configurations with white or reflective cell boundary conditions, are considered., Second, starting from the surface cosine current formulation, a two-zone three-layer multicell formalism for reduction of the heterogeneous flux expressions to equivalent homogeneous flux expressions for the “table” method is developed. The “outer (right side)” as well as “inner (left side)” Dancoff probabilities can be calculated for any particular layer., This formalism allows an infinite as well as a limited number of second-heterogeneity cells within a partial first-heterogeneity cell layer to be considered. Also, the number of the first- as well as second-heterogeneity cell types is quite general., An accurate, efficient, and compact interpolation procedure is used to calculate the basic collision probabilities. These are transmission and escape probabilities for shells in slab, cylindrical, and spherical geometries, as well as Dancoff probabilities for cylinders in square and hexagonal lattices., The use of the interpolation procedure is exemplified in a multilayer multicell approximation for the Dancoff probability, enabling a routine evaluation of the equivalence-based shielded resonance integral in highly complex lattices of slab, cylindrical, or spherical cells.