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Radiation Protection & Shielding
The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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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Latest News
Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
Martin Victor Polley
Nuclear Technology | Volume 71 | Number 3 | December 1985 | Pages 557-567
Technical Paper | Fission Reactor | doi.org/10.13182/NT85-A33678
Articles are hosted by Taylor and Francis Online.
It is widely experienced that operation with a low primary coolant pHT leads to heavy deposition on fuel-pin cladding in pressurized water reactors (PWRs). This is thought to be due principally to solubilities of corrosion products exhibiting negative temperature dependencies at low coolant pHT, leading to precipitation from the solution onto core surfaces. Solubilities also increase at low pHT values and this may be an additional reason for the increased deposition. Particulate deposition may also depend on coolant pHT. Operation at low coolant pHT may thus cause increased corrosion product activity transport, leading to higher dose rates around the primary circuit. The possible correlation between low pHT operation and steam generator channel head dose rates was investigated, using detailed data from nine Westinghouse PWRs. The coolant chemistry was quantified by calculating both the percentage of operating time at low pHT and a numerical “precipitation index” in order to establish the extent of operation below that coolant pHT above which little core crud deposition is expected. Time averaged pH’s were also calculated for each cycle. End-of-cycle dose rates were plotted against these coolant chemistry parameters on a plantby-plant basis and statistical tests were applied following linear regression analysis. Positive correlations were obtained and it was found that, for the limited number of plants in the survey, these correlations were between the categories “significant” and “probably significant” for cycle 1 and cycle 2 data.
