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Conference Spotlight
2026 Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
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
What’s the most difficult question you’ve been asked as a maintenance instructor?
Blye Widmar
"Where are the prints?!"
This was the final question in an onslaught of verbal feedback, comments, and critiques I received from my students back in 2019. I had two years of instructor experience and was teaching a class that had been meticulously rehearsed in preparation for an accreditation visit. I knew the training material well and transferred that knowledge effectively enough for all the students to pass the class. As we wrapped up, I asked the students how they felt about my first big system-level class, and they did not hold back.
“Why was the exam from memory when we don’t work from memory in the plant?” “Why didn’t we refer to the vendor documents?” “Why didn’t we practice more on the mock-up?” And so on.
Paul Thomet
Nuclear Technology | Volume 127 | Number 3 | September 1999 | Pages 259-266
Technical Paper | Fission Reactors | doi.org/10.13182/NT127-259
Articles are hosted by Taylor and Francis Online.
Feasibility studies of an advanced 900-MW(electric) pressurized water reactor (PWR) aiming at the total elimination of soluble boron during normal reactor operation (extended uranium cycle length of 16 GWd/t) are summarized.The neutronic consequences of this boron elimination on assembly design (poisoning, moderation ratio, cluster system, etc.) are presented. The specific assembly geometry has been optimized by taking into account a number of parameters, in particular the moderating ratio and thermal-hydraulic performances.The modifications that must be made to a standard PWR are studied (loading pattern and control rod management) to control the core with the same safety criteria as for the standard PWR, during the whole cycle, from power operation to cold shutdown. A new control rod system, with two different kinds of control rod clusters, has been developed. The first allows power control during operation while the second ensures cold shutdown. It is shown that these modifications do not require different technologies from those of present PWRs.
