Standards

ANSI/ASME/ANS RA-S-1.1-2024, Standard for Level 1/Large Early Release Frequency Probabilistic Risk Assessment for Nuclear Power Plant Applications, has just been published by the American Nuclear Society. The document, which is a joint standard developed with the American Society of Mechanical Engineers by the ANS/ASME Joint Committee on Nuclear Risk Management, received approval of the American National Standards Institute on February 29, 2024, and was issued on March 15, 2024.

Each month on the last Friday from 3:00 p.m. to 4:00 p.m. (ET), the American Nuclear Society’s Risk-informed, Performance-based Principles and Policy Committee (RP3C) holds a Community of Practice (CoP), which is open to all. On February 23, N. Prasad Kadambi, director of his eponymous engineering consultancy firm, presented “Technology-Inclusive Implications of ANSI/ANS-30.3-2022, Light Water Reactor Risk-Informed, Performance-Based Design.”

The American Nuclear Society has published the first voluntary consensus standard for nuclear reactor design that formally incorporates risk-informed, performance-based (RIPB) decision-making in July 2022. ANSI/ANS-30.3-2022, Light Water Reactor Risk-Informed, Performance-Based Design, tells reactor designers how they can incorporate RIPB principles and methods to ensure safety in new commercial light water reactor designs, and it includes a spectrum of options using both deterministic and risk-based approaches. As the first such standard, ANSI/ANS-30.3-2022 represents progress toward the adoption of RIPB principles for nuclear regulation and licensing—a shift the Nuclear Regulatory Commission was directed to make in the Nuclear Energy Innovation and Modernization Act, which became law five years ago.

Last month at the American Nuclear Society’s Risk-informed, Performance-based Principles and Policy Committee’s (RP3C’s) Community of Practice (CoP), Brandon Chisholm presented “Development of a Risk-Informed and Performance-Based Safety Case for TerraPower’s Molten Chloride Reactor Experiment (MCRE).” RP3C holds a CoP on the last Friday of the month from 3:00 p.m. to 4:00 p.m. (ET), and participation is open to all professionals interested in RIPB principles and practices. Chisholm’s January 26 presentation is available to stream on YouTube.