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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.
B. Goel
Nuclear Science and Engineering | Volume 69 | Number 1 | January 1979 | Pages 99-104
Technical Note | doi.org/10.13182/NSE79-A21291
Articles are hosted by Taylor and Francis Online.
It is well established that helium formed in stainless steel by various (n,α) processes has a pronounced effect on its mechanical and dimensional properties. The anomalous production of helium in nickel-based alloys is known to take place via the two-step process: 58Ni(n,γ)59Ni(n,α)56Fe. For thermal neutrons, the 59Ni(n,α)56Fe cross section used to calculate the helium production differs strongly from the value obtained by the direct measurements of this cross section. In this Note, this discrepancy is discussed, and a value of 12.5 ± 1 b based on direct measurements is recommended for future calculations. For fast neutrons, the contribution due to the two-step process has been ignored in the past. It is demonstrated that this contribution is substantial, and it gains in importance as the neutron fluence increases. It is further shown that the usual practice to relate helium production data to thermal- and fast-neutron fluence is inadequate. The details of the neutron spectrum and the cross section are necessary to reliably predict the helium production rate.
