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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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Deep Space: The new frontier of radiation controls
In commercial nuclear power, there has always been a deliberate tension between the regulator and the utility owner. The regulator fundamentally exists to protect the worker, and the utility, to make a profit. It is a win-win balance.
From the U.S. nuclear industry has emerged a brilliantly successful occupational nuclear safety record—largely the result of an ALARA (as low as reasonably achievable) process that has driven exposure rates down to what only a decade ago would have been considered unthinkable. In the U.S. nuclear industry, the system has accomplished an excellent, nearly seamless process that succeeds to the benefit of both employee and utility owner.
Jerry B. F. Champlin
Nuclear Technology | Volume 8 | Number 3 | March 1970 | Pages 283-289
Paper | Analysis | doi.org/10.13182/NT70-A28675
Articles are hosted by Taylor and Francis Online.
The void space in a variety of objects can be obtained by a neutron activation method utilizing the normal argon content in the air filling the pores and voids of such samples. The activation reaction used is 40Ar(n, γ)41Ar which has a cross section of 0.63 b. Argon-41 decays by beta emission with a half-life of 1.85 h to the stable isotope of potassium, 41K. If the quantity of air in a sealed container is known, the air can be used as an activation “foil” to estimate the total flux seen by the sample while in the reactor. After standard air volumes have been evaluated, porous solids containing air can be analyzed for void space if placed under the same conditions of geometry and efficiency and the activity acquired used as a measure of the total air present relative to a standard. It is possible to use this technique with substances for which the porosity (void space/bulk volume) is difficult to measure in other ways.
