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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
2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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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
Framatome signs contracts with Sizewell C
French nuclear developer Framatome is slated to deliver key equipment for Sizewell C Ltd.’s two large reactors planned for the United Kingdom’s Suffolk coast.
The agreement, reportedly worth multiple billions of euros, was announced this week and will involve Framatome from the design phase until commissioning. The company also agreed to a long-term fuel supply deal. Framatome is 80.5 percent owned by France’s EDF and 19.5 percent owned by Mitsubishi Heavy Industries.
Dušan Babala, Kåre Hannerz
Nuclear Science and Engineering | Volume 90 | Number 4 | August 1985 | Pages 400-410
Technical Paper | doi.org/10.13182/NSE85-A18488
Articles are hosted by Taylor and Francis Online.
Current light water reactors (LWRs) depend for the protection of core integrity on a multitude of active systems and components, such as instrumentation, cables, electronic logics, relays, actuators, etc., and on human judgment. This approach to safety has led to a complex and expensive plant design in which all parts of the plant where these systems are present must be protected against damage due to, e.g., earthquake. It has also failed to persuade the public about the safety of the reactors because of the existing (but very small) probability of multiple failures leading to core meltdown. With the process inherent ultimate safety (PIUS) approach, this dependence on active systems is eliminated. The safety is now no longer a result of their intervention but is built into the thermohydraulics of the primary system itself. The PIUS primary system response to a number of severe anticipated transients without scram (ATWS) is described, as studied by means of a specially developed computer simulation program. The method is shown by which the thermohydraulic self-protection properties of the primary system terminates these ATWS transients, which could have severe consequences in a conventional LWR, with neither the core nor the rest of the plant suffering any damage (beyond the initial failure assumed). This has important economic consequences. The surveillance and control systems used to run the plant and the buildings in which they are housed can be designed as for a fossil plant, since they no longer have the ultimate responsibility for nuclear safety. The ensuing design simplification pays for the more expensive pressure vessel and primary system. Inherent safety is obtained as a bonus.