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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.
Feroz Ahmed, L. S. Kothari, Ashok Kumar
Nuclear Science and Engineering | Volume 46 | Number 2 | November 1971 | Pages 203-213
Technical Paper | doi.org/10.13182/NSE71-A22354
Articles are hosted by Taylor and Francis Online.
The dependence of neutron diffusion length on the size and shape of the cross-sectional area of infinitely long rectangular blocks of crystalline moderators (graphite and beryllium) has been studied using an energy-dependent transverse buckling. In conformity with the experimental results in graphite, the diffusion length is found to increase with a decrease in the transverse size of the assembly. It is further found that in assemblies with small transverse dimensions, pseudoequilibrium conditions are established fairly rapidly and reasons for this are discussed. On the other hand, in assemblies with intermediate transverse dimensions (cross-sectional area lying between 70 × 70 cm2 and 50 × 50 cm2 for graphite and between 30 × 30 cm2 and 20 × 20 cm2 for beryllium), even pseudo-equilibrium conditions are not established at very large distances from the source. Dependence of the diffusion length on the shape of the cross-sectional area is also investigated.
