The Nuclear Regulatory Commission (NRC) has published a proposed rule that removes the ALARA principle — standing for “as low as reasonably achievable” — from its regulations, replacing it with defined, fixed dose thresholds. It is one of the most long-awaited reforms in the American nuclear sector, which has operated under the current framework since the 1970s.
The ALARA principle required operators of nuclear plants, medical facilities, and universities to keep radiation exposure as low as reasonably achievable — that is, well below existing legal limits. The NRC itself has stated that ALARA “as a separate regulatory expectation can generate additional costs and complexity without a measurable safety benefit.” In its place, the NRC proposes adopting a system it considers more cost-efficient and less complex, based on existing federal dose limits.
The reform stems from Executive Order 14300, signed by Donald Trump on May 23, 2025. The stated goal is to expand US nuclear capacity from the current roughly 100 gigawatts to 400 gigawatts by 2050. The order criticized the linear no-threshold (LNT) model underpinning ALARA, calling such models lacking “sound scientific basis” and capable of producing irrational outcomes — such as requiring plants to guard against radiation levels lower than natural background. In response, the NRC has drafted a proposed rule that retains the LNT model for risk assessment purposes but removes the operational ALARA requirement.
The regulatory shift extends beyond power plants. The revision applies to the more than 50 operating commercial reactors and roughly 10 fuel cycle facilities, but also affects hospitals and universities that use radioactive materials. For new reactors and SMRs, the impact is even more direct: NRC Chair Ho K. Nieh has said he does not expect major changes in the operations of existing facilities, while the effect on new technologies will be more significant. Nieh added that designers of new technologies have been trying to hit a moving target, and that the new regulatory framework will address this uncertainty. He rejected the notion that the change amounts to a loosening of safety standards, stating that the agency is “raising the standard of regulatory clarity, not lowering the standard of safety,” and that dose limits remain unchanged — what is being eliminated is unnecessary ambiguity.
The nuclear industry had long complained that ALARA, in practice, had morphed into a principle of absolute minimization of exposure. Several industry groups argued it had effectively become equivalent to “as low as possible,” driving up costs to reduce radiation to levels well below what is necessary to protect public health. The NRC’s own regulatory analysis concludes that the proposed rule would generate net savings for the industry, for agreement state regulators, and for the agency itself. The Department of Energy had already moved in this direction: it rewrote its own regulations along similar lines last year, without a public rulemaking process, with rules applicable to its own reactors and those operated by contractors outside the national laboratory system.
With the rule now open for public comment, the path to final approval is underway. Final rules are expected by November, according to speakers at the agency’s public meeting. For designers of new modular reactors and microreactors, the executive order also provides an accelerated pathway to approve designs already tested by the Department of Defense or the Department of Energy, along with a high-volume licensing process for modular and microreactors featuring standardized applications. The direction is clear: less regulatory ambiguity, firm limits, defined timelines. American nuclear power needs certainty to build — and this reform delivers some of it in concrete terms.
