In 1971, the AEC proposed a radically new regulatory philosophy requiring all nuclear plants be designed to hold all radioactive emissions to levels such that "exposures were as low as practicable". In other words, there is no limit. And the criteria is not whether the benefit of further reduction outweighs the cost. The criteria is: can you afford the reduction?

This was such a departure from standard regulation that, despite their desperation to get plants on line, it did produce push back from industry. But after considerable debate the policy was formally adopted in 1975 with the wording changed slightly to "as low as reasonably achievable" or ALARA.

In practice, As Low As Reasonably Achievable is interpreted by the regulators to mandate any regulation that allows nuclear to remain competitive with alternate sources of power.