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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.
M. C. Billone, Y. Y. Liu
Fusion Science and Technology | Volume 8 | Number 1 | July 1985 | Pages 881-886
Tritium | Proceedings of the Sixth Topical Meeting on the Technology of Fusion Energy (San Francisco, California, March 3-7, 1985) | doi.org/10.13182/FST85-A40144
Articles are hosted by Taylor and Francis Online.
Models are developed to describe the steady-state percolation of tritium through the solid-breeder interconnected porosity to the purge stream, convection of tritium by the helium purge stream, and permeation of tritium through the structural material to the primary coolant system. Important parameters in the models are tritium generation rate, breeder microstructure, tritium species in the gas phase, temperatures, tritium diffusivities and permeabilities, and effectiveness of oxide barriers. The models are used to perform calculations for fusion-blanket conceptual designs. The results indicate that for isotopic swamping of the purge stream with protium and relatively high oxide impedance factors (∼100 for nonbreeder-side surfaces) the leakage rate from the blanket can be limited to less than 100 Ci/day for reasonable purge flow rates and pressure drops. However, for lower impedance factors and/or for decreased protium partial pressure in the purge, problems do arise with limiting the tritium leakage.