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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.
Yigal Ronen, Dror Regev
Nuclear Science and Engineering | Volume 66 | Number 1 | April 1978 | Pages 124-127
Technical Note | doi.org/10.13182/NSE78-A15196
Articles are hosted by Taylor and Francis Online.
The upper bound estimation method is applied for estimating perturbations in reactor theory calculations. The results of this method are numerically compared with the regular first-order perturbation theory. It is concluded from the comparison that first-order perturbation in the integral formalism gives the best estimate for the changes in eigen-values. For those cases in which first-order perturbation yields low estimates, it is possible to obtain lower and upper bounds by applying both methods. A discussion of the possibility of obtaining a rough estimation to a perturbation without knowing the unperturbed regular and adjoint fluxes is presented and demonstrated with a numerical example.