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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.
S. B. Kim, S. L. Chouhan, P. A. Davis
Fusion Science and Technology | Volume 60 | Number 3 | October 2011 | Pages 960-963
Measurement, Monitoring, and Accountancy | Proceedings of the Ninth International Conference on Tritium Science and Technology | doi.org/10.13182/FST11-A12575
Articles are hosted by Taylor and Francis Online.
The high mobility of tritium as HTO implies that, under steady-state conditions, the T/H ratio (or equivalently the HTO concentration) is the same in all water compartments of the environment. This is the basis of the specific activity (SA) model, which underlies almost all environmental tritium models. SA concepts apply to organically bound tritium (OBT) as well, since the OBT formed by a given plant process at a given time has a T/H ratio that reflects the ratio in the water that enters into that process. There is no empirical evidence that the bioaccumulation of tritium in aquatic and wetland plants will occur. OBT/HTO ratios less than one is consistently found in the laboratory where the HTO concentrations to which the plants are exposed can be held constant. These data suggest a value of 0.7 for the OBT/HTO ratio under equilibrium conditions in the laboratory. Theoretical considerations suggest that the value of the OBT/HTO ratio in plants is significantly different from one and, in most cases, greater than one. This is primarily due to the much longer residence time of OBT in plants as compared to HTO. The observed HTO concentrations are much higher than OBT concentrations, which makes OBT/HTO ratio smaller than unit in contrast with SA based expectations. In addition to this, the IMPACT model overpredicted HTO and OBT concentrations in plants and animals by a factor of 3 or 4, on average. This work is summary of the AECL funded research project (1).