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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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DOE fast tracks test reactor projects: What to know
The Department of Energy today unveiled 10 companies racing to bring test reactors online by next year to meet Trump's deadline of next Independance Day, leveraging a new DOE pathway that allows reactor authorization outside national labs. As first outlined in one of the four executive orders on nuclear energy released by President Trump on May 23 and in the request for applications for the Reactor Pilot Program released June 18, the companies must use their own money and sites—and DOE authorization—to get reactors operating. What they won’t need is a Nuclear Regulatory Commission license.
Donald A. Close
Nuclear Technology | Volume 32 | Number 2 | February 1977 | Pages 205-210
Technical Paper | Radioisotope | doi.org/10.13182/NT77-A31724
Articles are hosted by Taylor and Francis Online.
A prototype perimeter security system using a beam of gamma rays from 137Cs is extremely sensitive to interruptions of the beam. Monte Carlo calculations indicate that a 1-Ci source is adequate to protect an interval of 93 m. A gamma-ray source can easily be made bidirectional, which would allow ∼200 m of perimeter to be guarded. A system using a gamma ray having an energy in the range of 500 to 1000 keV would result in a minimum number of false alarms per year.
