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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Latest News
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.
Blair P. Bromley, Geoffrey W. R. Edwards, Pranavan Sambavalingam
Nuclear Science and Engineering | Volume 182 | Number 3 | March 2016 | Pages 263-286
Technical Paper | doi.org/10.13182/NSE15-19
Articles are hosted by Taylor and Francis Online.
Lattice and core physics modeling and calculations have been performed to quantify the impact of power/flux levels and power history on the reactivity and achievable burnup for 35-element fuel bundles made with thorium-based fuels, such as (Pu,Th)O2 and (233U,Th)O2. These bundles are designed to produce on the order of 20 MWd/kg burnup in homogeneous cores in a 700-MW(electric)–class pressure-tube heavy water reactor, operating on a once-through thorium cycle. Methods have been developed to model time-dependent power histories in lattice physics calculations that are more consistent with core physics analysis results. Results demonstrate that the impact of power/flux level and the modeling of time-dependent power histories on the core power distributions and achievable fuel burnup are modest for Pu/Th fuels but are more significant for 233U/Th fuels. Thus, to reduce the neutron capture rate in 233Pa and to increase fuel burnup and fissile utilization, there may be an incentive to develop solutions to reduce the time-average specific power in the fuel.