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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.
Harry J. Reilly, John D. Hansell, George L. Heath
Nuclear Science and Engineering | Volume 38 | Number 2 | November 1969 | Pages 135-142
Technical Paper | doi.org/10.13182/NSE69-A19518
Articles are hosted by Taylor and Francis Online.
A method of performing probability calculations for nuclear-reactor surface temperatures has been devised. The method gives consideration to the fact that some uncertainties may vary systematically over all the reactor or over some parts of it. The method does not depend on assumption of any particular form of the probability distributions. The method was used to do an example calculation for an MTR-type test reactor with plate-type fuel elements. It was shown that the calculated probability of failure, that is, that surface temperature exceeds coolant saturation temperature, lies closer to values obtained from the Deterministic Method than to values from the Statistical Method. The calculated probability value was identified as the probability of success at the instant of reactor startup. It was observed that the probability of success for continued operation might not be the same as the value for startup. The method gives an improved representation of the probability problem for reactor surface temperatures. However, there is still much to be learned about the various important distribution functions. In the present situation of inadequate knowledge of behavior and distributions of uncertainty factors, all such probability calculations must be regarded as providing only a rough approximation to the true probability of success for a reactor.