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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.
Koroush Shirvan, Mujid Kazimi
Nuclear Technology | Volume 184 | Number 3 | December 2013 | Pages 274-286
Technical Paper | Fission Reactors | doi.org/10.13182/NT13-A24985
Articles are hosted by Taylor and Francis Online.
An optimization search over all design parameters yields a boiling water reactor (BWR) with high power density (BWR-HD) at a power level of 5000 MW(thermal), equivalent to a 26% uprated Advanced BWR (ABWR), the latest version of operating BWR. This results in economic benefits, estimated to be [approximately]20% capital and operation and maintenance costs and similar total fuel cycle cost per unit electricity. A safety analysis of the BWR-HD was performed and compared with that of the ABWR. It covered a range of transients, involving a decrease in reactor coolant inventory or coolant system flow rate, changes in coolant temperature along with increase in reactor pressure, and a reactivity-initiated transient. The BWR-HD's different core flow velocity, feedwater flow rate, core inlet temperature, void coefficient of reactivity, pressure drop, core fuel loading, and volume of fluid in the core resulted in very different response to transients. In general, the 1.3-m-shorter core results in faster scram times and lower total positive reactivity insertions during the transients, which improves the BWR-HD's performance compared to that of the ABWR. The core remains covered and the pressure in the reactor pressure vessel never rises above the licensing limits during any of the simulated transients. The change in minimum critical power ratio for the BWR-HD was smaller than or equal to that of the reference ABWR in all of the six simulated transients. For the loss-of-coolant-inventory accidents and severe accidents, the BWR-HD qualitative performance was judged to be acceptable and could result in an improved response with the lower fuel and zirconium loading.