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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.
Daniel T. Willcox, James R. Parry
Nuclear Technology | Volume 205 | Number 10 | October 2019 | Pages 1302-1311
Technical Paper | doi.org/10.1080/00295450.2019.1590075
Articles are hosted by Taylor and Francis Online.
The Transient Reactor Test Facility has been restarted after more than 20 years in a safe standby condition. The plan to bring the reactor back into operation included a typical core characterization that was historically performed every time the core was reconfigured for a new experiment campaign. The core characterization included determining initial critical position of the control rods, a heat balance run for calibration of the nuclear instruments to enable the indication of reactor power, control rod worth measurements, and a series of three temperature-limited transients increasing in the amount of reactivity inserted as a step for the interpolation of set points for the reactor trip system and reactivity insertion limits. The heat balance and control rod worth measurements are discussed in this paper. After critical control rod position was determined, a heat balance operation was used to position the nuclear instruments for correct power indication. This was followed by control rod differential worth measurements to generate the control rod worth curves used by the automatic reactor control system for control of the reactor during transient operations. These restart evolutions are summarized here, and the results are compared to the historic measurements.