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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
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
TerraPower begins U.K. regulatory approval process
Seattle-based TerraPower signaled its interest this week in building its Natrium small modular reactor in the United Kingdom, the company announced.
TerraPower sent a letter to the U.K.’s Department for Energy Security and Net Zero, formally establishing its intention to enter the U.K. generic design assessment (GDA) process. This is TerraPower’s first step in deployment of its Natrium technology—a 345-MW sodium fast reactor coupled with a molten salt energy storage unit—on the international stage.
Ronald W. King, Erwin C. Filewicz
Nuclear Technology | Volume 52 | Number 1 | January 1981 | Pages 32-42
Technical Paper | Reactor | doi.org/10.13182/NT81-A32687
Articles are hosted by Taylor and Francis Online.
The Experimental Breeder Reactor II (EBR-II) is an unmoderated, sodium-cooled reactor with a design power level of 62.5 MW(thermal). The design uses a submerged pool concept in which the reactor and fuel handling components are contained in a primary tank filled with sodium. The in-tank fuel handling is done remotely with no visual contact of the fuel subassemblies or the in-tank portion of the fuel handling equipment. The fuel handling operations, therefore, depend on precise, predictable positioning of all equipment and subassemblies. In July 1978, during normal fuel handling operations, it was discovered that one of the subassemblies in the in-tank storage basket for reactor subassemblies was not in the proper position to be handled with the subassembly transfer arm. Months of diagnostic evaluation of the actual position and shape of the subassembly resulted in a full-size mockup of the equipment and of the subassembly involved. The diagnostic measurements were duplicated with the mockup, a special system for retrieving the subassembly was designed and built, and a procedure was prepared. Using the mockup, the special equipment and procedure were thoroughly tested, modified, and retested. The subassembly was retrieved from the storage basket and primary tank on May 11, 1979, with no major difficulties. During the time between the discovery of the problem and the retrieval of the sub-assembly, EBR-II reactor operations continued as normal except for minor inconveniences during fuel handling operations because of the position of the damaged subassembly. The overall success of this project gave confidence that abnormal situations of this type in a sodium-cooled, pot-type reactor can be handled, without visual contact, through careful planning and preparation.