ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Explore membership for yourself or for your organization.
Conference Spotlight
2026 ANS Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
Latest Magazine Issues
May 2026
Jan 2026
2026
Latest Journal Issues
Nuclear Science and Engineering
June 2026
Nuclear Technology
Fusion Science and Technology
Latest News
NRC proposes changes to its rules on nuclear materials
In response to Executive Order 14300, “Ordering the Reform of the Nuclear Regulatory Commission,” the NRC is proposing sweeping changes to its rules governing the use of nuclear materials that are widely used in industry, medicine, and research. The changes would amend NRC regulations for the licensing of nuclear byproduct material, some source material, and some special nuclear material.
As published in the May 18 Federal Register, the NRC is seeking public comment on this proposed rule and draft interim guidance until July 2.
M. A. Sweeney, J. N. Olsen
Nuclear Science and Engineering | Volume 89 | Number 3 | March 1985 | Pages 233-246
Technical Paper | doi.org/10.13182/NSE85-A17544
Articles are hosted by Taylor and Francis Online.
The Sandia National Laboratories Particle Beam Fusion Accelerator PBFA II is expected to produce significant amounts of prompt penetrating radiation from bremsstrahlung. In the present study the radiation environment for two voltages, 30 and 5 MV, has been calculated using a three-dimensional electron-photon transport code. Because of the facility design changes required with the high-voltage lithium ion option, most calculations were done at 30 MV. The dose to personnel, ∼1 mrad for the 30-MV option, is acceptable. Reliable operation of electronic components, however, requires significant changes to systems in various stages of completion. Shielding and relocation options that minimize interference with the completion schedule of the accelerator and with its operation and maintenance have been investigated. We find that an array of control devices located in the east alcove of the basement should be moved to the main control/monitor screen room in the low bay. A thicker top cover on the vacuum chamber and a higher water level in the pulse-forming section allow electronics in the screen room to cope with the hard 30-MV spectrum. A two-stage shield has been designed to protect the KrF laser and its associated electronics, which cannot be removed from the basement. The two-stage shield consists of a thick steel bottom cover on the vacuum chamber and a thick shield wall on the north alcove of the basement.