Comments of the Nordic Society for Radiation Protection, NSFS, on
the draft 2005 Recommendations of ICRP
· NSFS wishes to commend ICRP for its openness and the efforts to consult iteratively, beginning with first principles and successively advancing to a more detailed proposal.
· NSFS welcomes a revision of the 1990 Recommendation of ICRP – that document was first drafted almost 20 years ago and there is scope for some amendments. However, the present consultation concerns the first actual text ever seen. While this text has a number of useful features, it still requires considerable editing and amendments in order to be-come the authoritative document expected from ICRP as a basis for international and na-tional legislation for the next 10-15 years.
· Furthermore, it is a significant drawback that the ‘foundation documents’ mentioned in various contexts are not yet available, and apparently will not become available for con-sultation until after the end of the consultation period on the main document. It is difficult to comment on what amounts to a summary when the underlying information is not avail-able!
· Therefore, and considering that completion of the revision is not extremely urgent, NSFS strongly recommends that sufficient time be taken to consider comments, and
that an updated version of the draft Recommendations be circulated for a second and final round of consultation before ICRP takes any final decision.
· NSFS notes that with respect to genetic risk, ICRP intends to revert to its 1977 position of calculating the risk for 2 generations only, while the 1990 Recommendations included a risk estimate covering all future generations. This will surely be regarded by many as a reduction of the level of protection, and the reasons behind the change are not obvious.
· A new method of calculating detriment is proposed, but it is difficult to understand how the new calculations have been performed and how the results differ from what emerged in the 1990 Recommendations.
· The weighting factor for breast is increased, but it is not clear why – NSFS is not aware of any major increase in the risk of breast cancer. Given these observations, NSFS
that the next version of the draft Recommendations should contain clear and comprehensible explanations of and rationales behind
- the components of the genetic risk (how much of the change depends on lower risk of multifactorials, etc, and how much on the reversion to 2 generations?)
- the calculation of detriment (what is the effect of new wR, of new wT, and of the change to using incidence instead of mortality?)
- the calculation of breast cancer risk.
· NSFS notes that very shortly after the printing of Publication 92, a paper by Dr Kellerer (apparently the main author of Publication 92), criticising some of the proposals and con-clusions in Publication 92, appeared in the open literature. ICRP should make sure that the final version of the Recommendations contain stable and well explained wR’s.
THE GENERAL SYSTEM OF PROTECTION
· NSFS welcomes the reinstatement of justification in the system and would encourage ICRP to stress even more that justification is an inherent part of protection, although deci-sions on justification are often taken ‘above’ the radiological protection expert.
· NSFS understands that it may be easier to explain the system if optimisation is seen as the third, rather than intermediate second, step. There is a certain appeal in the idea that first, everybody is assured of a basic level of protection, then there is a further duty to reduce doses as far as reasonably achievable. NSFS sees this as a change of the manner of ex-plaining the system, rather than any radical change, and does not expect that the end result of application of the system of protection will be very different than with the 1990 Rec-ommendations. However, a specific “foundation document” on optimisation would be much welcome and is expected to clarify some still unclear parts of the concept optimisa-tion in the system of radiation protection. The disaggregating process that results in a “dose matrix” should be developed.
· In the discussion on factors influencing the choice of dose limits and constraints there are comparisons made with the normal background radiation. Even if it is said that existence of natural background radiation does not provide any justification for additional exposure there is a remaining impression when reading the draft that the size of the deviation from natural radiation, rather than the corresponding risk of a dose, is the basis for justification of a dose limit or constraint. Comparison with natural radiation dose is usually made for educational purposes in order to give some perspectives of radiation but it seems inappro-priate to give natural radiation a status of basis for Recommendations on radiation protec-tion. Editorial changes are therefore advisable to avoid that impression and focus more on the risk (as done for “minimum value of any constraint”).
· The ‘generic’ constraints provided in the draft Recommendations are really just indicating that a constraint must never exceed the dose limits and should normally be below the lim-its. This will not be of much help to any regulator, and there is a risk that the very valu-able homogeneity achieved in protection will be lost. The desire to reduce the number of different numerical Recommendations is commendable, but if it leads to an even greater number of different values in practical applications, nothing has been gained.
· The draft Recommendations does not discuss any alternatives to the present limits. NSFS understands that stability in the fundamental limits is desirable, but the dose limit for the public is not really a practical tool and appropriate the time-span for averaging of doses (just one year? 5 years as now? Life-time?) would have been worth some discussion.
· The difference between constraints and limits is muddled in the present draft. Both of these instruments have a role, at least in occupational protection work. In reality, limits remain the last line of defence while constraints are the standard tool and benchmark. Thus, the system really has four, not three, components. Given these observations, NSFS
that the next version of the draft Recommendations should contain more discussions on
- Justification as a part of the system, but usually performed by others,
- The role and likely outcome of optimisation,
- The dose limits and constraints in terms of risk and how comparison with natural radiation can be used not as being a basis for Recommendations but a means of setting perspectives,
- Suggested specific constraints (e.g., the 0.3 mSv constraint proposed in Publication 77 should be mentioned explicitly to indicate that this is still valid and compatible with the 1 mSv ‘generic’ constraint now mentioned in the draft),
- Limits, which should be presented as a separate and final fourth part of the system (rarely to be used in day-to-day work but important as a last resort).
PROTECTION IN MEDICINE
This topic is treated very superficially in the draft Recommendations, making a strange con-trast to the increased attention to medical radiation problems in recent ICRP reports. At the very least, the draft Recommendations could make reference to those reports.
Many paragraphs are also written out of context and can therefore be misunderstood. An ex-ample of this is the unfortunate statement that optimisation is given less attention. This can be taken as an excuse for not aiming at optimised procedures.
There are also other medical-like exposures that should be addressed, e.g. security checks at airports, search for drugs inside or outside suspects, exposures in connection with crime in-vestigations.
APPLICATIONS AND REGULATORY SYSTEMS
· It is argued in the draft that the present system of Recommendations set out in Publication 60 with subsequent publications by ICRP has been too complex and difficult to apply in international and national guides and legislation. Therefore, any step forward to simplify the Recommendations in that sense is welcome assuming the basic structure is kept in a logic framework. The question to be asked is of course: will the proposed new Recom-mendations be easier to apply? We have no answer to that question but recommends it should be considered
· The 1990 Recommendations contained a very useful chapter on the methods of ensuring that the system of protection is really applied and works. To our surprise, there is not any-thing at all about this important aspect in the draft Recommendations. ICRP should re-member that for many users, the new Recommendations will be the only ICRP document that they will ever see, so while the advice given in the 1990 Recommendations and in, e.g., Publication 75 remains largely correct, it needs to be repeated in the new Recom-mendations.
that the possible problems that might occur with the practical application of the new Recom-mendations are considered
and strongly proposes
that a chapter be inserted, corresponding to Chapter 7 of the 1990 Recommendations.
Stockholm, 21 December 2004
On behalf of the Nordic Society for Radiation Protection (NSFS)
Jan Olof Snihs