ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Explore membership for yourself or for your organization.
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!
Latest Magazine Issues
Jul 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
September 2025
Nuclear Technology
August 2025
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.
Brian C. Kiedrowski, Forrest B. Brown, Jeremy L. Conlin, Jeffrey A. Favorite, Albert C. Kahler, Alyssa R. Kersting, D. Kent Parsons, Jessie L. Walker
Nuclear Science and Engineering | Volume 181 | Number 1 | September 2015 | Pages 17-47
Technical Paper | doi.org/10.13182/NSE14-99
Articles are hosted by Taylor and Francis Online.
Nuclear criticality safety analysis using computational methods such as a Monte Carlo method must establish, for a defined area of applicability, an upper subcritical limit (USL), which is a calculated multiplication factor k that can be treated as actually subcritical and is derived from a calculational margin (combination of bias and bias uncertainty) and a margin of subcriticality. Whisper, a nonparametric, extreme-value method based on sensitivity/uncertainty techniques and the associated software are presented. Whisper uses benchmark critical experiments, nuclear data sensitivities from the continuous-energy Monte Carlo transport software MCNP, and nuclear covariance data to set a baseline USL. Comparisons with a traditional parametric approach for validation, which requires benchmark data to be normally distributed, show that Whisper typically obtains similar or more conservative calculational margins; comparisons with a rank-order nonparametric approach show that Whisper obtains less stringent calculational margins.