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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.
T. J. Hoffman
Nuclear Science and Engineering | Volume 50 | Number 3 | March 1973 | Pages 300-302
Technical Note | doi.org/10.13182/NSE73-A28985
Articles are hosted by Taylor and Francis Online.
In this Note an expression is derived for estimating the change in detector response due to perturbations in a fixed source system. This expression, developed with variational theory, includes a correction to first-order perturbation theory which accounts for the flux change caused by the perturbation. The derivation is extended to altered systems, and an expression is obtained which improves first-order perturbation theory by accounting for changes in the unaltered forward and adjoint fluxes. With this variational approach, all transport calculations can be performed in the unperturbed unaltered system.