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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 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.
K. Lisa Reed, Farzad Rahnema, Dingkang Zhang, Dan Ilas
Nuclear Technology | Volume 206 | Number 11 | November 2020 | Pages 1686-1697
Technical Paper | doi.org/10.1080/00295450.2020.1757962
Articles are hosted by Taylor and Francis Online.
In this paper, a set of stylized numerical benchmark problems is developed. These problems are based on the Oak Ridge National Laboratory preconceptual design of a fluoride-salt-cooled small modular advanced high-temperature reactor, or SmAHTR, that uses prismatic fuel assemblies with cylindrical pins/rods containing tri-isotropic fuel particles. A detailed description of the benchmark problems is achieved by closing several outstanding design gaps and modifying the coolant channel shape to reduce bypass flow for improved coolant and fuel temperature distributions. The benchmark problems, while stylized, retain the important thermal-hydraulic and reactor physics features (e.g., fuel particles) necessary for benchmarking tools for reactor core analysis.
In addition to the full description, detailed reference results such as the eigenvalue (keff) and fuel pin and assembly-averaged fission density distributions are provided for five benchmark problems: full-length fuel assemblies with control rods fully withdrawn and inserted, and full core with all control rods withdrawn, all control rods fully inserted, and some control rods fully inserted (near-critical core). The provided results are calculated using the continuous-energy Monte Carlo code MCNP.