The evolving system of radiological protection: the nuclear industry perspective

The World Nuclear Association (WNA) believes that the case for a significant change to the system of protection is not compelling, and any rationalizations need to be carefully judged. We have concern at some apparent over-simplification and vagueness by ICRP in its furtherance of the search for simplicity and coherence. Any changes should be evolutionary, allowing reasonable regulatory stability, and should assure adequate protection of human health and safety and the protection of the environment, promote optimal use of public and private resources and help build public trust and confidence. The proposal for a maximum constraint of 20 mSv pa on occupational exposure is too inflexible. The control of exposures in the range 20-50 mSv pa should take account of exceptional circumstances and is a matter best left for discussion and agreement between the local stakeholders - i.e., the regulators, the operator and the workforce. Our principal concern is the proposal for a maximum constraint of 0.3 mSv pa on public exposure. This level, equivalent to one tenth of average natural background exposure, cannot be justified on public health grounds or in comparison with the range of exposures from background or other practices (e.g., medical). It represents a major and unjustified change from the current limit of 1 mSv pa, and its application in a regulatory regime would have a very significant impact on the nuclear industry, particularly on uranium mining and milling and many other current major nuclear sites. There would be significant cost implications with insignificant consequential gains in health protection. To carefully examine the issue of practical implications, one must look beyond the very low off-site impacts from routine radioactive discharges from typical nuclear facilities. In particular, there is a wide range of specific situations in the nuclear industry for which a maximum constraint of 0.3 mSv pa set at the international level would be unduly unrestrictive. (A set of key examples is listed herein.) In our view, the current system comprising of the dose limit (1 mSv pa) and the ALARA Principle provides the necessary flexibility and tools to regulators for addressing any country specific or site specific settings, and there are already good examples of this. Again, we believe that this matter is best left for discussion and agreement between the local stakeholders rather than at an international level. We strongly support the need to establish an international approach to defining a level of dose below which society may legitimately maintain that an individual is adequately protected., and hence the allocation of further resources to control the source on radiological health grounds would be inappropriate. WNA considers that this dose is not less than a few tens of micro-sieverts. This approach should be supported by guidance on the appropriate level of conservatism within dose assessments, both in the context of exclusion/clearance/exemption and critical groups in general. WNA supports the continued use of the term 'ALARA, economic and social factors being taken into account'. Collective dose is a useful concept in the optimisation of occupational exposure: in addition it needs to be supplemented by the consideration of the number of workers exposed at the higher levels and by wider pragmatic experience. Public collective dose is of very limited utility in decision making, and little if any weight should be given to exposures at long timescales and exceedingly trivial levels of individual exposure. WNA welcomes both the lead taken by ICRP to bring the protection of non-human biota into a coherent overall framework addressing the totality of radiological protection, and the recognition that the current system has in practice provided an appropriate standard of environmental protection. On this basis the development of the future system of protection must not impose a disproportionate burden on operators. The focus for protection of non-human biota should be at the species and ecosystems level whilst endorsing that humans are protected at the individual level. Noting that all energy sources give rise to environmental detriments of different kinds, the fundamental issue is not simply how to avoid environmental harm, but how to balance and optimise the totality of benefits and detriments. (author)