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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.
A. Trivedi, R.B. Richardson, D. Galeriu
Fusion Science and Technology | Volume 28 | Number 3 | October 1995 | Pages 982-987
Tritium Safety | Proceedings of the Fifth Topical Meeting on Tritium Technology in Fission, Fusion, and Isotopic Applications Belgirate, Italy May 28-June 3, 1995 | doi.org/10.13182/FST95-A30533
Articles are hosted by Taylor and Francis Online.
Tritiated watero (HTO) represents the mosl important occupational and environmental exposures to tritium, as far as radiation protection is concerned We have studied the dynamics of HTO and organically bound tritium* (OBT) in urine, feces and blood from male workers at 100–300 d following an acute intake of HTO. Blood and cumulative 24 h urine and fecal samples were collected and analyzed for HTO and OBT. The activity concentrations oi HTO in urine and HTO in feces were in equilibrium and were representative of HTO in the body water (HTO in blood). The ratio of bound tritium per gram hydrogen (Bq·H−1) in organic matter in feces (OBTfeces) to urine (OBTurine) was 1.0 ± 0.1. Similarly, the ratios of OBTblood to OBTurine and OBTblood to OBTfeces were 0.9 ± 0.2 and 1.1 ± 0.2, respectively. These results suggest that, providing an equilibrium condition exists, a measurement of the tritium activity per unit mass of organic matter in urine or feces can provide an assessment of the specific activity of tritium in the organic fraction ol the soft tissue. The activity concentrations of HTO and OBT in urine samples, from a few days up to 300 d post-exposure, were examined for the clearance kinetics of HTO in urine and OBT in urine. The early presence of OBT in urine indicated that a portion of tritium from the ingested HTO is rapidly fixed into organic constituents of the body. The half-life for the longer-term component of OBT in urine is comparable to the half-life for the longer-term component of HTO in urine. This close relationship between the longer-term excretion of HTO in urine and OBT in urine suggests that most of the HTO produced in its longer-term component is a by-product of metabolized OBT. This work has demonstrated that OBT is excreted in urine in all examinations, up to 300 d post-exposure to HTO, and that a fraction of the metabolized OBT is also excreted in feces.
