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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Fusion Science and Technology
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.
D. R. Hanchar, M. S. Kazimi
Fusion Science and Technology | Volume 4 | Number 2 | September 1983 | Pages 395-400
Tritium | doi.org/10.13182/FST83-A22896
Articles are hosted by Taylor and Francis Online.
A transient tritium permeation model is developed based on a simplified conceptual DT-fueled fusion reactor design. The major design features in the model are a solid breeder blanket, a low pressure purge gas in the blanket and a high pressure helium primary coolant. Tritium inventory in the breeder is due to diffusive hold-up and solubility effects. Diffusive hold-up is assumed to be the dominant factor in order to separate the solution for the breeder tritium concentration. The model was applied to the STARFIRE-Interim Reference Design, whose system parameters yielded a breeder tritium inventory on the order of grams. The breeder pellets (average radius, 10−3 cm) reach their steady-state tritium content in approximately 4 hours from startup, assuming continuous full power operation. Both the steady-state breeder tritium concentration and the time to reach that steady-state are proportional to the square of the pellet radius.