Mr. Fleming is an internationally recognized expert in probabilistic risk assessment (PRA) of nuclear power plants and its use in risk-informed and performance-based (RI-PB) decision making. His 51 years of experience include performance of PRAs on light-water reactor (LWR) and high-temperature gas-cooled reactors. He was a principal author of the Licensing Modernization Project guidance document for RI-PB design and licensing of advanced non-LWRs in NEI 18-04, which has been endorsed by the U.S. Nuclear Regulatory Commission in Regulatory Guide 1.233. Mr. Fleming was Chair of the ASME/ANS Working group responsible for developing the PRA Standard for Advanced Non-LWRs, ASME/ANS-RA-S-1.4-2021. He was the 2021 recipient of the American Nuclear Society Tommy Thompson Award for Lifetime Achievement in Nuclear Safety and inducted into the National Academy of Engineering in 2020.
