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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.
W. P. Barthold, J. C. Beitel, P. S. K. Lam, Y. Orechwa, S. F. Su, R. B. Turski
Nuclear Technology | Volume 46 | Number 3 | December 1979 | Pages 525-528
Technical Paper | Nuclear Power Reactor Safety / Reactor | doi.org/10.13182/NT79-A32361
Articles are hosted by Taylor and Francis Online.
To avoid high energy releases in unprotected loss-of-flow accidents, cores can be designed such that the removal of sodium would add only a small amount of reactivity or even a negative reactivity to the reactor. Reduction in sodium void reactivity can be achieved by changing either the geometry or composition of the core. Pancake, modular, and heterogeneous core configurations were investigated. Heterogeneous cores showed sodium void reactivities in the 2-dollar range with only small penalties in doubling time when compared with the equivalent homogeneous cores. Liquid-metal fast breeder reactors using U-Th fuel in the form of metal, oxide, or carbide show negative sodium void reactivities but doubling times above 30 yr.