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 Nuclear Energy Conference & Expo (NECX)
August 24–27, 2026
Dallas, TX|Hilton Anatole
Latest Magazine Issues
Jun 2026
Jan 2026
2026
Latest Journal Issues
Nuclear Science and Engineering
July 2026
Nuclear Technology
Fusion Science and Technology
Latest News
Valar’s Ward 250 reaches criticality in Utah
El Segundo, Calif.–based start-up Valar Atomics has taken its Ward 250 test reactor critical at the Utah San Rafael Energy Lab (USREL), becoming the second company in the Department of Energy's Reactor Pilot Program to reach the milestone, and, according to the DOE, the first to do so outside a national laboratory.
The DOE celebrated the achievement in a June 18 announcement, describing it as a "zero-power fueled criticality demonstration." The news follows a similar update for Antares Nuclear's Mark-0 reactor, which the DOE said achieved criticality at Idaho National Laboratory earlier this month.
Advanced Reactor Safety (ARS)
Technical Session
Tuesday, June 18, 2024|3:15–5:00PM PDT|Palm A
Session Chair:
Matthew Denman (Kairos Power)
Alternate Chair:
Aslak Stubsgaard
Session Organizer:
To access paper attachments, you must be logged in and registered for the meeting.
Register NowLog In
Literature Review of Preliminary Initiating Events for a Gas-Cooled Fast Reactor Conceptual Design
3:15–3:35PM PDT
Steven Krahn (Vanderbilt Univ.), Megan Harkema (Vanderbilt Univ.), Irfan Ibrahim (Vanderbilt Univ.), Hangbok Choi (General Atomics), John Bolin (General Atomics), Eric Thornsbury (EPRI)
Paper
On the Applicability of the General Transient Initiating Event Group for Advanced Reactors
3:35–3:55PM PDT
Mostafa Hamza (NCSU), Huafei Liao (X-energy), Mark Cursey (Jensen Hughes), Karl Fleming (Technology Insights), Mihai A. Diaconeasa (NCSU)
The State of Art of the Human Failure Events Dependency Analysis Methods
3:55–4:15PM PDT
Mostafa Hamza (NCSU), Mihai A. Diaconeasa (NCSU)
Management of Risks Associated with Application of Novel Materials in Novel Operating Environments in Novel Reactor Designs
4:15–4:35PM PDT
R. Youngblood (INL), S. Ferrara (INL)
Risk Metrics for Advanced Reactors
4:35–4:55PM PDT
Eric Thornsbury (EPRI), Stephen Hess (Jensen Hughes), Jeffrey Julius (Jensen Hughes), Chloe Howard (Jensen Hughes)
Presented by Doug Hance (EPRI)
