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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.
Charles J. Mueller, David C. Wade
Nuclear Technology | Volume 91 | Number 2 | August 1990 | Pages 215-225
Technical Paper | Safety of Next Generation Power Reactor / Nuclear Saftey | doi.org/10.13182/NT90-A34429
Articles are hosted by Taylor and Francis Online.
The approach and methods used at Argonne National Laboratory to assess core damage probability in risk assessments for innovative liquid-metal reactor (LMR) designs using metal-fueled cores in pool configurations are outlined. Bounding estimates for the predicted frequency of core damage from all unprotected initiating events are developed by establishing a set of reference scenarios from traditional anticipated transient without scram events. Sources of uncertainty are described and categorized. A probabilistic treatment is used to propagate the various uncertainties through safety analyses to determine their effects on limiting reactor parameters. For example, probability distributions for safety margins to selected core temperatures are propagated from sensitivity studies and estimates of the underlying uncertainties in reactivity feedback coefficients. Considerable self-cancellation of many of the contributors to core response uncertainties is demonstrated analytically. Upper bound probabilities of core damage are then calculated for the LMR cores currently being designed. The results show that these designs have much lower probabilities of suffering core damage than are predicted in published risk assessments for commercial power reactors. Finally, design strategies that can be used to reduce these already low probabilities to almost arbitrarily low values are discussed.