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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.
P. E. Tremblay, D. G. Andrews
Nuclear Science and Engineering | Volume 44 | Number 1 | April 1971 | Pages 1-11
Technical Paper | doi.org/10.13182/NSE71-A18899
Articles are hosted by Taylor and Francis Online.
From the basic conservation equations in two-phase hydrodynamics, an expression for the pressure gradient has been derived. A key quantity in the denominator of that expression is recognized as the ratio of the actual-to-sonic two-phase mass fluxes. This dimension-less ratio is seen as a generalization of the Mach number. The expression for the sonic mass flux is shown to be an equation-of-state depending only on local properties of the fluid. The conditions that make the dimension-less ratio equal to 1 are shown to correspond to the critical conditions.