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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.
Toru Obara, Hiroshi Sekimoto
Nuclear Science and Engineering | Volume 130 | Number 3 | November 1998 | Pages 386-390
Technical Note | doi.org/10.13182/NSE98-A2014
Articles are hosted by Taylor and Francis Online.
The positive neutron temperature coefficient of reactivity of a dilute plutonium-water solution is discussed analytically and numerically. It is explained by the competition of the temperature sensitivity coefficients of microscopic thermal cross sections of fissile materials and absorbers. The use of 176Lu, 180Ta, or 167Er, which have absorption resonances at low energy, in the solution makes it possible for the neutron temperature coefficient of reactivity of a dilute plutonium-water solution to be negative.
