Part 57 Should Be Built for High-Volume Licensing

How quickly the United States can deploy a new generation of advanced nuclear reactors will depend in large part on whether the Nuclear Regulatory Commission (NRC) can license them efficiently and at scale. The NRC's proposed "Part 57" rule is designed to do exactly that—making licensing faster, more standardized, and more repeatable by scaling regulatory requirements to the consequences a reactor can actually pose. Reactors that cannot cause significant harm beyond their site boundary could qualify for streamlined review, standardized designs, and manufacturing-based licensing. But the proposed rule is ambiguous about its own purpose: it is framed around a loosely defined category of reactors rather than around the high-volume licensing it is meant to enable—an ambiguity that could generate boundary disputes, complicate implementation, and weaken the rule's long-term durability.

The Breakthrough Institute submitted a comment to the commission recommending changes to resolve this and other structural issues before the rule is finalized. Most importantly, BTI urges the NRC to make clear that Part 57's central purpose is high-volume licensing, not a technology category, and to ensure its eligibility criteria, security requirements, environmental review, and emergency planning are calibrated to demonstrated risk and administrable at scale. BTI also recommends aligning Part 57 with the NRC's broader advanced-reactor framework (Part 53) so developers can move efficiently from first-of-a-kind demonstrations to repeated commercial deployment without re-litigating settled issues. As the comment puts it, "[w]ith changes, Part 57 can become a durable and effective licensing framework because it is more focused, not because it is less rigorous."