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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.
Sanjay Gupta, Feroz Ahmed, Suresh Garg
Nuclear Science and Engineering | Volume 125 | Number 3 | March 1997 | Pages 362-370
Technical Paper | doi.org/10.13182/NSE97-A24281
Articles are hosted by Taylor and Francis Online.
Results are reported for the space-dependent neutron spectra and tritium breeding ratio (TBR) in a proposed Li + C blanket of a deuterium-tritium fusion reactor. The multigroup diffusion equation is solved as an eigenvalue problem for three concentrations of lithium in graphite. The effect on the value of TBR of increasing the fraction of low-energy neutrons in a completely thermalized source is studied. A comparison of neutron spectra as obtained in the Li + C and 3He + C systems is also made. The results show that TBR increases with the concentration of lithium in graphite as well as with the fraction of low-energy neutrons in the source. [Essentially the same value of TBR (= 0.277) is obtained for the Li + C system with a lithium to graphite concentration of 4 x 10-2 as for a 3He + C system with a natural density of 3He.] Moreover, TBR attains an almost constant value for assembly thicknesses greater than -20 cm. Also, if a source with an increased fraction of low-energy neutrons is used, the effect is more pronounced in the 3He + C system for the range of lithium concentrations considered.
