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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 Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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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.
Jae-Hyuk Eoh, Seyun Kim, Sang-Ji Kim, Seong-O Kim
Nuclear Technology | Volume 160 | Number 2 | November 2007 | Pages 216-232
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT07-A3894
Articles are hosted by Taylor and Francis Online.
The KLFR is a pool-type lead-cooled fast reactor, which has a core thermal output of 900 MW(thermal), and a reactor vessel auxiliary cooling system (RVACS) is employed to secure reliable decay heat removal (DHR) during the worst anticipated design-basis condition. Since the RVACS design is based on reliable and economic considerations, a sufficiently large DHR capacity and compact reactor vessel size are desirable. However, these two requirements compete with each other because a sufficient DHR capacity can be achieved by a larger vessel size with a consequential heavy lead coolant weight. An advanced RVACS concept that has a larger capacity with a more compact vessel size was developed. To increase the DHR capacity of the KLFR, which uses natural-air circulation cooling, the feasibility of heat transfer enhancement by introducing new design concepts to essentially reduce the heat transfer resistance of the radial heat transfer elements was investigated. As a result of this work, the parametric analysis results showed that the passive DHR capacity of the KLFR can be substantially increased by up to 24% when compared with the classical RVACS concept, and this feature makes a compact reactor vessel very feasible. With the proposed advanced RVACS concept, one could expect that the heat removal capacity of an RVACS-type passive DHR system will be increased.