US — The Nuclear Regulatory Commission (NRC) proposed a new rule in early July 2025 to revise radiation exposure regulations. The proposal removes references to the "as low as reasonably achievable" (ALARA) principle and introduces a graded approach to managing doses below regulatory limits.

The NRC states the rule addresses vagueness in terminology rather than changing the underlying science of current regulations. The agency estimates the changes will save industries approximately $9.5 million annually. The proposal also includes updates to regulations on the use of equipment to monitor radiation exposures.

Organizations currently in compliance with existing regulations will remain in compliance under the proposed rules without making changes. The NRC states that no consensus-supported, regulation-ready alternative model to the linear non-threshold (LNT) model exists. The agency also states it is unlikely there is a threshold level of exposure below which a biological response does not occur.

According to the NRC proposal, the "reasonableness test" in ALARA decision-making has become an expectation that any available means to reduce dose should be applied without further consideration. The proposal notes that implementing the ALARA requirement presented challenges, including a lack of clarity on when dose reduction is sufficient, excessive subjectivity, and susceptibility to selective or inconsistent enforcement.

In 2020, President Trump issued an executive order describing the LNT model as irrational and lacking a sound scientific basis. During the first Trump administration, the NRC rejected a petition to adopt hormesis as part of its scientific framework.