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
Jan 2026
Latest Journal Issues
Nuclear Science and Engineering
April 2026
Nuclear Technology
February 2026
Fusion Science and Technology
Latest News
2025 annual assessments out for U.S. reactors
The Nuclear Regulatory Commission has released its 2025 annual performance assessments of the country’s 95 operating commercial nuclear reactors. And of the 95 reactors, all but five earned the highest marks.
Nuclear power plant assessments can fall under one of five categories: Licensee Response, Regulatory Response, Degraded Cornerstone, Degraded Performance, and Unacceptable Performance. Ninety reactors fell under Licensee Response, the highest performance category in safety and security. Plants that achieve this level of performance are subject to a Reactor Oversight Process (ROP) baseline inspection.
Fernando Ferrante, Stuart Lewis
Nuclear Technology | Volume 207 | Number 3 | March 2021 | Pages 413-423
Technical Paper | doi.org/10.1080/00295450.2020.1775451
Articles are hosted by Taylor and Francis Online.
This work explores recent developments in severe accident analysis and risk assessment to inform and expand on these perspectives. Variations in nuclear reactor safety policy, reactor designs, extent of use of risk information in decision making, and other aspects can impact how safety policies regarding nuclear installations are developed and implemented. In particular, the relationship of nuclear policy in the United States is explored with regard to quantitative risk criteria or goals and their relationship with health objectives. In the United States and many countries around the world, health objectives are defined with regard to the potential impact to the public in terms of “early” fatalities and “latent” fatalities. This paper discusses how the link between these health objectives and quantitative risk goals have been developed and how recent information may change the perspective originally held when the policies were established (e.g., that there would be a significant margin between the risk of operating nuclear facilities and these goals). Given that these metrics play a significant role in how current risk applications are used for operating nuclear reactors, especially when results are to be compared with thresholds, it is important to recognize the evolution and current understanding of associated embedded margins. Given the additional 30 years of insights, the expansion of risk application in the commercial nuclear reactor industry, and improvements in methodologies and computing capabilities, significant additional information has been gained. These insights are discussed and presented in this paper.