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Division Spotlight
Radiation Protection & Shielding
The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
Meeting Spotlight
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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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Latest News
Argonne’s METL gears up to test more sodium fast reactor components
Argonne National Laboratory has successfully swapped out an aging cold trap in the sodium test loop called METL (Mechanisms Engineering Test Loop), the Department of Energy announced April 23. The upgrade is the first of its kind in the United States in more than 30 years, according to the DOE, and will help test components and operations for the sodium-cooled fast reactors being developed now.
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.