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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
Standards Program
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.
Baofu Lu, Eric Williams, Jerry Mauck, Michael Howard, Richard Wood, Edward L. Quinn
Nuclear Technology | Volume 202 | Number 2 | May-June 2018 | Pages 101-105
Technical Paper | doi.org/10.1080/00295450.2017.1416878
Articles are hosted by Taylor and Francis Online.
The purpose of this paper is to provide an overview of the development and assessment of the Diversity and Defense-in-Depth (D3) strategy for the TerraPower Traveling Wave Reactor-Prototype (TWR-P) advanced nuclear power plant. The TWR-P digital control system (DCS) is currently being designed by TerraPower. The instrumentation and control (I&C) design and configuration were based on standard digital control products. The control systems making up the DCS were selected because of their applicability to the functions required by TerraPower and the U.S. Nuclear Regulatory Commission. The installation of a digital-based plant protection system and other systems throughout the TWR-P enhances safety in many areas when compared to the previous generation of analog-based instrumentation systems.
Nuclear facilities have increased their use and reliance on digital technology in systems and equipment (e.g., I&C, electrical systems, and fluid systems). In addition to I&C, examples of safety-related equipment that may use digital technology include emergency diesel generators, pumps, valve actuators, motor control centers, breakers, priority logic modules, time-delay relays, and uninterruptible power sources.
In the United States and around the world, engineering and licensing activities in standards and guidance have been, and are being, developed to address this important consideration in protecting safety-related systems. This paper addresses the latest in standards and guidance development as well as a review of the application of this guidance in the specific case cited.