U.S. Nuclear Regulatory Commission Modernizes Security Rules for Advanced Reactors
The U.S. Nuclear Regulatory Commission (NRC) has been actively modernizing its security regulations for advanced reactors, particularly small modular reactors (SMRs) and non-light water reactors. In August 2024, the NRC published a proposed rule offering alternative physical security requirements, allowing licensees to potentially field fewer or no onsite armed responders if the design supports it, relying instead on offsite law enforcement. This rule also permits secondary alarm stations to be located offsite and allows delay to be achieved through engineered systems, distance, or natural features, rather than solely physical barriers. On March 30, 2026, the NRC finalized its Part 53 rule, a risk-informed, technology-inclusive framework for licensing advanced reactors, which took effect on April 29, 2026. This rule, along with new sections in Part 73, adopts a 'consequence-based approach' for physical security, cybersecurity, and access authorization. A proposed rule in June 2026 further aims to shift phy...
