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
Mar 2026
Jul 2025
Latest Journal Issues
Nuclear Science and Engineering
March 2026
Nuclear Technology
February 2026
Fusion Science and Technology
April 2026
Latest News
NRC approves TerraPower construction permit
Today, the Nuclear Regulatory Commission announced that it has approved TerraPower’s construction permit application for Kemmerer Unit 1, the company’s first deployment of Natrium, its flagship sodium fast reactor.
This approval is a significant milestone on three fronts. For TerraPower, it represents another step forward in demonstrating its technology. For the Department of Energy, it reflects progress (despite delays) for the Advanced Reactor Demonstration Program (ARDP). For the NRC, it is the first approval granted to a commercial reactor in nearly a decade—and the first approval of a commercial non–light water reactor in more than 40 years.
Hesham Khater, Sandra Brereton, Mike Singh
Nuclear Technology | Volume 168 | Number 2 | November 2009 | Pages 381-386
Shielding | Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 2) / Radiation Protection | doi.org/10.13182/NT09-A9213
Articles are hosted by Taylor and Francis Online.
Prompt doses from X-rays generated as result of laser beam interaction with target material are calculated at different locations inside the National Ignition Facility. The maximum dose outside a target chamber diagnostic port is [approximately]10 mSv for a shot utilizing the 192 laser beams and 1.8 MJ of laser energy. The dose during a single bundle shot (eight laser beams) drops to [approximately]0.4 mSv. Doses calculated outside the target bay (TB) doors and inside the switchyards (SYs) [except for the 5.33-m (17-ft 6-in.) floor level] range from a few microsieverts to [approximately]110 Sv for 192 beams and scale down proportionally with a smaller number of beams. At the 5.33-m (17-ft 6-in.) floor level, two diagnostic ports are directly facing two of the TB doors, and the maximum doses outside the doors are 0.5 and 0.16 mSv, respectively. Shielding each of the two TB doors with 6.35-mm-thick Pb (¼-in.) reduces the dose by a factor of 50. One or two bundle shots (8 to 16 laser beams) present a small hazard to personnel in the SYs.