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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.
Ivan Michieli
Nuclear Science and Engineering | Volume 117 | Number 2 | June 1994 | Pages 110-120
Technical Paper | doi.org/10.13182/NSE94-A20077
Articles are hosted by Taylor and Francis Online.
Buildup factors for various shielding materials exhibit large variations in magnitude and in curve shapes as a function of penetration depth as a result of the stochastic nature of the scattering processes for different incident photon energies. In a quest for adequate functional representation of point isotropic gamma-ray buildup factor data, a family of functions based on an expanded polynomial orthogonal set is introduced.The approximation function has the form .In the foregoing formula, a and β are generally constants that differ for each material, and in that respect, this formula presents a family of functions, while Ai are independent parameters of the function. This is not always valid, and for some materials, modifications are introduced where besides Ai, an additional independent parameter is (β while a remains constant throughout the whole energy domain.A polynomial-based function approach is validated as a possible choice [besides the well-known geometrical-progression (G-P) function] for point-kernel calculations. Results of approximations to exposure point isotropic buildup factors for water, concrete, and iron with four and for lead and beryllium with five independent parameters of presented function are in good agreement with the basic data within 4%, over the standard data domain. The results are compared with five-parameter G-P function fitting on the maximum-percentage-relative-error basis. The validity of using the independent parameters of the function to interpolate buildup factors for intermediate source energies is ascertained.