Evolution not revolution

Abstract

Possibly the most important words in the latest memorandum from ICRP (on page 129 of this issue) are in the title and abstract. To title the item `The evolution of the system of radiological protection' immediately dispels the greatest concern many of us had over the route that ICRP had been taking, namely the wholesale replacement of the current system of radiological protection by some `new' system. Now, however, the justification for the next recommendations is presented in terms of summarising and extending the recommendations introduced in Publication 60, and in some ten reports since, to give a single set that can be simply and coherently expressed. As is said in the abstract, `A radical revision is not envisaged'.Nonetheless there are still some significant changes in the proposed `2005 recommendations' - we now have a date - that will need careful evaluation in terms of their practical application, preferably before their adoption by the Commission. Most of these are not yet sufficiently explicit in the memorandum for this to be done, but it is to be hoped that the ICRP Committees, especially Committee 4 which has as its title `The Application of the Commission's Recommendations', will use the internal discussions on the draft that is to be prepared late in 2003 to carry out this evaluation. Committee 4 will suffer from the untimely death of its Chairman, Bert Winkler, but still has probably the most important task of all the Committees with respect to the acceptance by the radiation protection community of the new recommendations.There are still, in principle, three principles: Justification. Justification has, however, been promoted out ofradiological protection except for medical applications. The system of protection to be applied to `already justified' sources will be reduced, for protection of workers and members of the public, to the following two principles. Constraints. The use of the term `constraint' supersedes the `Protective Action Level' of the previous memorandum, and is probably a better term, but it is clear that there will be a need for a number of constraints applicable to different sources, and these continue to be related to the levels of concern about individual doses with concern - or lack of concern - about natural background as the benchmark. It is noteworthy that in the section dealing with setting constraints there is no mention of the benefit from or acceptability of the source to which the constraint is to apply. To those who have remarked over the years on the lack of concern of people over exposure to natural radon, the acceptance almost without question of medical exposures irrespective of dose level and the violent antipathy to even very low exposures from nuclear power or radioactive waste, this may seem to sidestep an important attribute of setting constraints which are defined to be `for each source'. There also remains an ex Cathedra statement which can be traced back to the earlier arguments regarding trivial dose that `If the individual is sufficiently protected from a source, then society is also protected from that source'. But not sufficiently protected apparently as there is still a need for the following principle. Optimisation. Optimisation applies both to single individuals and to groups, and is expressed in what is called a `more qualitative' manner. Operationally it is said to be `a frame of mind, always questioning whether the best has been done in the prevailing circumstances'. This approach and the involvement of stakeholders in reaching decisions on the optimum allocation of resources to protection for particular circumstances are in accord with current practical procedures for optimisation. There may well still be a role for decision aids to structure inputs to such stakeholder involvements, and indeed the `disaggregated matrix' that collective dose will become is cited as such a `decision-aiding technique'. The retention of the concept of exclusion recognises a pragmatic regulatory need. The clarification and full explanation of this concept and the definition of what sources and exposures are to be excluded from the system of protection that we are promised will be very helpful, but not easy to arrive at in a coherent manner for both natural and artificial sources. The use of the concept of `authorised release' for all other circumstances is entirely in line with the proposals from the NEA Expert Group (The Way Forward in RadiologicalProtection - an NEA Expert Group Report (NEA 2002), reviewed on page 117 of the previous issue of this journal) and should lead to some regulatory simplification.The provisions for protection of patients are essentially the same as the current system, which is to be welcomed as this system is now finding acceptance and application throughout the medical professions.With respect to protection of the living environment the very recent ICRP publication on the framework (ICRP Publication 91) is to form the basis for the approach. ICRP recognises that there are many other players in this arena and that it will not be possible in the new recommendations to do much more than propose an approach that is compatible with the protection of humans.There is much to be welcomed in this memorandum of explanation as to the current thinking within ICRP. The thing most to be welcomed is the production of the memorandum itself. None of us will retrospectively be able to accuse the Commission of keeping us in the dark or of not giving us a chance to have an input. Detailed consideration of the actual recommendations will, however, have to await the detailed proposals. A`well-developed draft' is promised for discussion at the 11th IRPA Congress in Madrid in May 2004. Given that the intention is to produce the recommendations in 2005 this is likely to be the culmination of the process of consultation with the profession that effectively started with the 10th IRPA Congress in Hiroshima in 2000. Societies and other bodies should have their review and commenting procedures ready and waiting - there will not be much time.