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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Ho Nieh nominated to the NRC
Nieh
President Trump recently nominated Ho Nieh for the role of commissioner in the Nuclear Regulatory Commission through the remainder of a term that will expire June 30, 2029.
Nieh has been the vice president of regulatory affairs at Southern Nuclear since 2021, though he is currently working as a loaned executive at the Institute of Nuclear Power Operations, where he has been for more than a year.
Nieh’s experience: Nieh started his career at the Knolls Atomic Power Laboratory, where he worked primarily as a nuclear plant engineer and contributed as a civilian instructor in the U.S. Navy’s Nuclear Power Program.
From there, he joined the NRC in 1997 as a project engineer. In more than 19 years of service at the organization, he served in a variety of key leadership roles, including division director of Reactor Projects, division director of Inspection and Regional Support, and director of the Office of Nuclear Reactor Regulation.
Gilles Champion, Josette Forestier, Thérèse Vergnaud
Nuclear Technology | Volume 74 | Number 1 | July 1986 | Pages 14-26
Technical Paper | Fission Reactor | doi.org/10.13182/NT86-A33815
Articles are hosted by Taylor and Francis Online.
The efforts made by Electricité de France to reduce exposure from the two-component neutrongamma radiation fields inside the pressurized water reactor (PWR) building are described. Most of the attention has been focused on the problem of neutron exposure relative to the problem of achieving a highly efficient confinement within the reactor cavity and the state of the art of personnel neutron dosimetry. A description of the general neutron calculation scheme that links the characteristics of the neutron fields escaping from the reactor vessel to the dose equivalent rate cartographies inside the reactor building is provided. Numerous measurements have been carried out to check the reference radiation sources involved in the calculation scheme and its predictions, increasing confidence in the calculational results. During the design of neutron shielding, it is necessary to take into account many requirements, particularly those of accessibility, safety, and normal operation. Some shielding materials commonly used on French PWRs are presented. The emphasis placed on the evolution of shieldings designed to prevent irradiation through the three main weaknesses of the primary concrete shield (access pit, primary bunkers, and refueling pool bottom) shows that they should become increasingly sophisticated. A comparison between the former shielding designs for three-loop PWRs and the latter for four-loop PWRs is made for this purpose.