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Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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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Latest News
First astatine-labeled compound shipped in the U.S.
The Department of Energy’s National Isotope Development Center (NIDC) on March 31 announced the successful long-distance shipment in the United States of a biologically active compound labeled with the medical radioisotope astatine-211 (At-211). Because previous shipments have included only the “bare” isotope, the NIDC has described the development as “unleashing medical innovation.”
Lorenzo P. Pagani, George E. Apostolakis, Pavel Hejzlar
Nuclear Technology | Volume 149 | Number 2 | February 2005 | Pages 129-140
Technical Paper | Reactor Safety | doi.org/10.13182/NT149-129
Articles are hosted by Taylor and Francis Online.
Passive safety systems are commonly considered to be more reliable than active systems. The lack of mechanical moving parts or other active components drastically reduces the probabilities of hardware failure. For passive systems, it is necessary to introduce the concept of functional failure, i.e., the possibility that the loads will exceed the capacity in a reliability physics framework. In this paper we analyze the passive cooling of a gas-cooled fast reactor, and we use an importance-sampling Monte Carlo technique to propagate the epistemic uncertainties and to calculate the probabilities of functional failures. The results show that functional failures are an important contributor to the overall failure probability of the system and, therefore, should be included in probabilistic risk assessments. A comparison with an alternative active design is considered also. The results show that the active system can have, for this particular application, better reliability than the passive one.