NRC is (sort of) getting rid of "as low as reasonably achievable" standard

Complicating matters, a number of people have advocated for something called hormesis, in which small doses of radiation purportedly promote the cellular repair of damage from other sources. The evidence for this is even spottier, and when the NRC was petitioned to adopt hormesis as part of its scientific framework during Trump’s first term, it rejected the petition. Given its acceptance of an LNT model of exposure risks, the NRC had chosen exposure standards that fell under the general term of ALARA: as low as reasonably achievable. If any exposure to radiation poses a risk, then minimizing it is the clearest way to protect the health of people who work with radioactive substances. The challenge there is that it’s possible to set exposure limits that people outside the industry regularly exceed each time they board a commercial aircraft. So, the word “reasonable” plays an outsized role while remaining highly subjective. Critics have charged that it precipitates an endless cycle of reasonable exposure limits leading to searches for additional ways to lower them further, or of adoption without cost considerations. And here, the NRC is acknowledging that there have been issues. “In essence, the reasonableness test that is supposed to be inherent to ALARA-related decision-making has gradually become an expectation that if a means of dose reduction is available, regardless of its reasonableness in relation to the total dose and the amount of reduction, it should be applied without further consideration,” its new proposal suggests. In the past, the NRC has attempted to address this by attaching a financial value to each unit of exposure based on estimates of the value of healthy life developed elsewhere. But in the new proposal, it accepts that “there have been challenges in the implementation of the ALARA requirement, namely a lack of clarity of when dose reduction is deemed sufficient, excessive subjectivity, and susceptibility for selective or inconsistent enforcement.” So, it’s giving up on a term that it now views as a source of confusion. One of the key things here is that the LNT model of exposure risks isn’t going away. In its earlier denial of petitions that it change its standards, the NRC had concluded that “in the absence of convincing evidence that there is a dose threshold or that the health effects of low levels of radiation are fully understood, the LNT model for cancers and genetic effects was appropriate for formulating radiation protection standards and planning radiation protection programs.” In the proposed new rules, that logic is left intact. “The NRC finds that no consensus-supported, regulation-ready alternative model to the LNT model exists at this time,” it states. More specifically, it states, “It is unlikely there might be a threshold level of exposure below which biological response does not occur. Such a threshold could only occur if DNA repair processes were totally effective in that dose range or if a single radiation track were unable to produce an effect.” It’s worth noting that the NRC is making that decision despite the fact that Trump issued an executive order that describes LNT and then calls it irrational. “The NRC utilizes safety models that posit there is no safe threshold of radiation exposure and that harm is directly proportional to the amount of exposure,” the order reads. “Those models lack sound scientific basis and produce irrational results.” The agency is keeping LNT in place despite being specifically ordered to reconsider it. With LNT intact, the scientific backing for ALARA remains in place. So, the new proposed regulations largely focus on calling it something else. “The NRC proposes to remove references to the ALARA principle, which rests on the LNT model’s assessment of risks from very low doses of radiation, from its regulations,” the proposed changes say. “Instead, the NRC would apply a less-subjective, graded approach to managing doses below regulatory limits.”