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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.
T. Lefvert
Nuclear Science and Engineering | Volume 42 | Number 3 | December 1970 | Pages 267-271
Technical Paper | doi.org/10.13182/NSE70-A21216
Articles are hosted by Taylor and Francis Online.
A multigroup, collision-probability, order-of-scattering approach is made to the slowing down solution of the neutron transport equation in a heterogeneous, non-multiplying medium with sources. Introducing first-collision probabilities in the Liouville-Neumann series solution of the neutron flux, the series may be summed and a transport matrix defined. If a flat source distribution in the region is assumed, this matrix is typical of the medium and of the geometrical configuration only and links, in an explicit way, sources and resultant fluxes. In a multiplying system without external sources it is also possible to use the above transport model when determining the effective neutron multiplication factor by the fission probability matrix method.