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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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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.
Joffrey Dorville, Jacob Tellez, Conner Glatt, Andrew Osborne, Jenifer Shafer, Jeffrey King
Nuclear Technology | Volume 208 | Number 1 | December 2022 | Pages S26-S51
Technical Paper | doi.org/10.1080/00295450.2022.2072649
Articles are hosted by Taylor and Francis Online.
The Megawatt Implementation of a NuclEar ReActor using Low-enrichment uranium (MINERAL) is designed to deliver 2 MW(electric) of steady-state electricity to a colony established on the surface of Mars with a minimum lifetime of 10 years. The main challenge associated with a low-enrichment uranium fission surface power system is reducing the total mass, which will be higher than that of an equivalent high-enrichment uranium system. Optimizing the mass of the system is crucial to limit the amount of Earth-Mars cargo needed to deploy a MINERAL unit. The use of yttrium hydride as a moderator has shown promise in reducing the overall mass of the reactor. An in-house Python framework evaluates the neutronic, thermal-hydraulic, and heat rejection performance throughout the design process. The final design iteration uses a CO2 Brayton cycle cooled by a passive heat rejection system consisting of six panels with a total surface area of 4752 m2. The cylindrical core is fueled with low-enrichment uranium monocarbide with 0.83 wt% of pure 157Gd moderated with yttrium hydride and surrounded by a beryllium oxide reflector. The reactivity is controlled by ten control drums and a central control rod, which provide enough margin to operate the reactor and ensure its subcriticality in case of a submersion accident. The mass of the core with the reflector, reactivity control system, and shield is 7.2 tonnes.
