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Human Factors, Instrumentation & Controls
Improving task performance, system reliability, system and personnel safety, efficiency, and effectiveness are the division's main objectives. Its major areas of interest include task design, procedures, training, instrument and control layout and placement, stress control, anthropometrics, psychological input, and motivation.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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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Nuclear new build procurement considerations
It may seem counterintuitive, but the best time to enhance the ability to support operations and maintenance for a new plant is before construction starts. This is one of many lessons learned by the currently operating nuclear fleet. As construction and startup of many nuclear facilities was completed, it quickly became evident that the ability to efficiently support operations and maintenance was limited. Most of the information necessary to establish and manage procurement of spare and replacement items, maintenance, and configuration of the facilities was unavailable and had to be gathered on a case-by-case, “on-demand” basis. Absence of necessary information and the associated challenges resulted in the need for staff augmentation and multiyear-long projects to develop equipment bills of material and maintenance programs and to perform technical evaluations for the huge quantities of spare and replacement items being requested.
Joonhong Ahn
Nuclear Technology | Volume 117 | Number 3 | March 1997 | Pages 316-328
Technical Paper | Radioactive Waste Management | doi.org/10.13182/NT97-A35346
Articles are hosted by Taylor and Francis Online.
Redistribution of vitrified weapons-grade plutonium placed in the proposed Yucca Mountain repository is investigated based on the pure-colloid transport model for plutonium and the pure-solute transport model for plutonium, uranium, and boron. In the pure-colloid model, colloids carrying plutonium are assumed to settle out of groundwater in the fractures by floccu-lation. In the pure-solute model, 239Pu, 235U, and boron are transported through fractures by advection and diffuse into the rock matrix with sorption retardation. Both models show that 239Pu stays in the vicinity of the repository and decays there to 235U. All the 239Pu that originally exists in the repository reaches the bottom end of 200-m fractures as 235U. Boron spreads in the geologic medium during the glass leaching period and quickly disappears after the end of the leach time. Concentrations of 239Pu and 235U are found to be too small for autocatalytic criticality.