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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.
C. W. J. McCallien
Nuclear Science and Engineering | Volume 50 | Number 3 | March 1973 | Pages 290-293
Technical Note | doi.org/10.13182/NSE73-A28982
Articles are hosted by Taylor and Francis Online.
Exact and first-order perturbation formulas that give changes in the eigenvalue of the discrete multigroup neutron diffusion equation are obtained. Various errors arising during the evaluation of these formulas are discussed. It is shown that for exact theory to give greater precision than first-order theory the fluxes must be sufficiently well converged to display the changes in them due to the perturbation. The reader is encouraged to assess the likely outcome of errors in his own calculations.
