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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
2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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
College students help develop waste-measuring device at Hanford
A partnership between Washington River Protection Solutions (WRPS) and Washington State University has resulted in the development of a device to measure radioactive and chemical tank waste at the Hanford Site. WRPS is the contractor at Hanford for the Department of Energy’s Office of Environmental Management.
Alan H. Wells, Albert J. Machiels
Nuclear Technology | Volume 176 | Number 3 | December 2011 | Pages 387-394
Technical Paper | Radiation Transport and Protection | doi.org/10.13182/NT11-A13315
Articles are hosted by Taylor and Francis Online.
According to the U.S. Nuclear Regulatory Commission's guidance based on concerns for potential channeling of neutrons between absorber particles, the criticality safety of transportation systems should not rely on credit for >75% of the boron in fixed neutron absorbers. The 75% efficiency (or effectiveness) factor was first formulated in 1987 for a cask to transport spent fuel from the Fermi Unit 1 (Fermi-1) fast breeder reactor. Fermi-1 fuel was highly enriched (25.6 wt%), and a critical condition could possibly be achieved in a dry environment. The 75% factor was later expanded to include low-enriched light water reactor (LWR) spent fuel, although the latter cannot achieve a critical state without the presence of a moderator. Under flooded conditions, the net effect of channeling is significantly reduced because the neutrons are nearly isotropically scattered by the moderator and impact the neutron absorber from all possible directions. Under dry conditions or under conditions representative in neutron attenuation measurements for absorber qualification, the neutrons impact the absorber mostly perpendicularly, and neutron channeling is maximized. The effect of neutron channeling for the Fermi-1 fuel and for a typical LWR fuel shipment was quantified using a methodology developed to apply experimental transmission data to calculations of the neutron angular distribution at the neutron absorber sheet, yielding the strength of the neutron channeling effect for a particular fuel type and cask basket geometry. These analyses show that neutron absorber qualification via a collimated neutron transmission measurement conservatively bounds the neutron channeling effect. Further imposition of a 75%-only credit leads to an overly conservative amount in neutron absorbers. For transport applications of LWR spent fuel, this results in increased costs with no measurable benefits to criticality safety.