Radiological protection, optimisation, and regulatory reform.

The principle of optimisation of protection is a cornerstone of the system of radiological protection (RP). The practical implementation and interpretation of optimisation, particularly at low doses and dose rates, is a long-recognized challenge and has often been subject to robust and spirited debate. At present we seem to have unprecedented interest and momentum for reflection on RP recommendations and standards, and with it the opportunity to collaboratively develop creative solutions to such challenges in support of a sustainable future. Potential solutions should be informed by science as well as a wide range of social and economic factors, and thoroughly and critically evaluated accordingly. In the United States (US), Executive Orders (EOs) have led to relevant proposed rule changes from the US Nuclear Regulatory Commission (NRC), including a proposed rule entitled "Reforming and Modernizing the NRC's Radiation Protection Framework." This paper argues that the proposal is rushed, imprecise, and insufficient by highlighting a few illustrative examples of how the proposed rule as written is inconsistent with international (e.g., International Commission on Radiological Protection) and national (e.g., US National Council on Radiation Protection and Measurements) recommendations and guidance. For example, the proposed rule claims that adherence to regulatory dose limits provides a sufficient level of protection, and that beyond prescribed actions at certain thresholds there is no need for further incorporation of the prevailing circumstances (i.e., no need to optimise protection) below these dose limits. National authorities of course have the purview to decide what is most appropriate and effective from a regulatory standpoint, but diverging from the broader consensus requires a clear, thoughtful, thorough, and transparent argument that is missing from the current proposal.