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Division Spotlight
Young Members Group
The Young Members Group works to encourage and enable all young professional members to be actively involved in the efforts and endeavors of the Society at all levels (Professional Divisions, ANS Governance, Local Sections, etc.) as they transition from the role of a student to the role of a professional. It sponsors non-technical workshops and meetings that provide professional development and networking opportunities for young professionals, collaborates with other Divisions and Groups in developing technical and non-technical content for topical and national meetings, encourages its members to participate in the activities of the Groups and Divisions that are closely related to their professional interests as well as in their local sections, introduces young members to the rules and governance structure of the Society, and nominates young professionals for awards and leadership opportunities available to members.
Meeting Spotlight
ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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
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.
James E. Tarpinian
Nuclear Technology | Volume 87 | Number 2 | October 1989 | Pages 429-432
Technical Paper | TMI-2: Health Physics and Environmental Release / Nuclear Safety | doi.org/10.13182/NT89-A27733
Articles are hosted by Taylor and Francis Online.
The dose reduction objectives for the Three Mile Island Unit 2 reactor building (RB) were designed to lower the dose rates in working areas so that the total collective dose to workers would be as low as reasonably achievable. As part of these objectives, a large-scale effort was devoted to the decontamination of RB surfaces. The presence of very high removable surface contamination levels, sometimes in excess of 1.7 × 103 Bq/cm2 (4.6 µCi/100cm2), contributed to high airborne radioactivity conditions, which necessitated the extensive use of respiratory protection. It became an objective of the decontamination program, therefore, to reduce the removable contamination levels to such an extent that the use of respirators could be reduced or even eliminated. The progress of the decontamination program was hampered when it was discovered that large areas of the RB were becoming recontaminated. Recontamination rates were measured to be ∼1.5 Bq/cm2·day−1 (4.1 × 10−3 µCi/100cm2·day−1). After a series of tests, it was determined that the air handling systems in the RB were distributing radioactivity from highly contaminated surfaces. Cascade impactor studies of the aerosols indicated a bimodal distribution of particle sizes. Particles >20-µm activity median aerodynamic diameter (AMAD) accounted for 30% of the collected activity and particles <5-µm AMAD were associated with 60% of the activity. Examinations by optical and electron microscopy and Raman spectroscopy helped determine that the larger particles were organic dusts associated with the air handling systems and the smaller particles were associated with the boric acid dissolved in decontamination water. Reducing the airflow through the air cooler fans and restricting the airflow to the highly contaminated D-rings helped to reduce the recontamination to 4 × 10−2 Bq/cm2·day−1 (1.1 × 10−4 µCi/100cm2·day−1). Subsequently, the recontamination of surfaces due to airborne vectors ceased to be an operational concern. Further decontamination of the floors enabled a significant reduction in the use of respiratory protection equipment.
