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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.
Richard B. Nicholson
Nuclear Science and Engineering | Volume 18 | Number 2 | February 1964 | Pages 207-219
Technical Paper | doi.org/10.13182/NSE64-A18320
Articles are hosted by Taylor and Francis Online.
A generalized method for estimating the energy release in hypothetical fast-reactor meltdown accidents is formulated. A modification of the Bethe-Tait method is derived from this more general formulation, and comparisons are made to an improved method, programmed for the IBM-7090 computer. Two basic assumptions are utilized: that the reactivity effects during disassembly can be calculated from perturbation theory, and that the decrease in density during disassembly can be ignored in the equations of hydrodynamics. It is shown that the threshold equation of state used in the Bethe-Tait method tends to cause an overestimate of the energy release for weak and moderate excursions, and that the saturated vapor pressure must be considered in those cases. The dependence of energy release upon prompt-neutron generation time, initial power level, rate of reactivity insertion, and Doppler effect is investigated.