The scope of radiological protection

Draft document: The scope of radiological protection
Submitted by Jukka Laaksonen, Director General, STUK - Radiation and Nuclear Safety Authority
Commenting on behalf of the organisation

Comments of STUK - Radiation and Nuclear Safety Authority, Finland, to the ICRP draft “The Scope of Radiological Protection Regulations” June 19, 2006 Main comments 1. The concepts of exclusion, exemption and clearance are well established and widely used in radiation protection to avoid unnecessary regulation. Provided that the draft RP06 from June 5, 2006 includes only a short section on this important topic a separate building block document might be needed. However, it should be shorter and less complicated than the current draft. Actually, some paragraphs of this draft confuse the reader unnecessary. 2. The document contains too much history of unsuccessful efforts in the development of the currently quite unambiguous system of exclusion, exemption and clearance. Those efforts were useful in their time and contributed to the development towards the current state of the art but are unnecessary burden in this document. 3. The discussion on alleged mistranslations of especially the term “clearance” is unnecessary and disturbing in this draft document. We radiation protection professionals with miscellaneous native languages discuss internationally on different concepts in English. However, the English word for certain concept and the many different meanings of that word in English language is not important for non-native English persons. What is important is the understanding of the essence of the concepts, which we have to translate in to our native language and to introduce in our legislation. 4. In this document, exclusion is categorically related to legislation and exemption to regulators. This means that exclusion and exemption are de facto defined by taking a stand on an appropriate legal infrastructure. This is contradictory to what is correctly stressed in the concluding reflections (148) and elsewhere in the document, that there are different legislative cultures and diverse regulatory approaches, and therefore, exclusion and exemption may be introduced in national regulations in different ways. Many countries have indeed introduced exemptions in legislation and will certainly continue to do so in the future. Please modify e.g. paragraph (c) of the executive summary and (3) in the main text, to loosen such categorical relations. 5. It is stated in paragraph (a) of the Executive summary “The Commission´s radiological protection recommendations are not limited in extent and cover all types of radiation exposure situation regardless of the size and origin of exposure”. It is consistent with this comprehensive approach to explain basic ideas and examples that characterize the nature of excluded exposure situations and exempted practices. In other words, it would be useful for ICRP to develop the general framework and concepts and refrain from endorsing or imposing numerical values for exclusion and exemption in terms of radionuclide content or concentrations for use by national authorities. Numerical values may be country specific and depend on circumstances and are a too fixed way of defining the scope of radiation protection regulations in the Recommendations. 6. Especially, introducing numerical “exclusion levels” would cause much more confusion and new questions than what they could ever solve. All the situations where these values (40 Bq/m3 for radon, 1 Bq/kg alpha, 10 Bq/kg for beta and gamma) could be applied are already dealt with appropriately, sufficiently and unambiguously using the concepts of exemption, clearance, authorised releases and action levels. Introducing a “two level” system would just confuse. These values are not needed! 7. The odd and unfortunate concept of “exemption from intervention” is discussed broadly in section 5.5. and a generic intervention exemption level of 1 mSv is recommended. It would be much better to keep the exemption in its original meaning, exemption of practices and sources within practices, than confuse those who wish to apply the ICRP Recommendations. In situations where intervention would be used as a tool for reducing doses, i.e. in emergency or existing exposure situations, optimization based on averted dose, number of people exposed and societal and economic circumstances in the given situation and the particular country is the tool to be recommended. 8. Discussion on dichotomous approaches to control “artificial” and “natural” exposure situations rightly points out variable controllability of exposures as one reason. On the other hand also people’s expectations and perceptions are mentioned as sources of dichotomy. The discussion fails to consider other aspects that influence people’s expectations and perceptions. People are in many natural exposure situations free to choose while exposure from human actions is often imposed on them. Further, there can be inequalities in the distribution of benefit and harm. In the case of natural radiation people may consider that their personal benefits outweigh the harm caused to them from the particular situation. Furthermore, the main concepts dealt with in paragraph (131) also omit inequalities from discussion on exclusion and exemption. The statement on good governance and ethical approach does not mention that both detriment and benefit have to be considered. The reference to individual freedoms does not consider the distribution of harm and benefit. We consider it to be ethically correct to restrict individual freedom from causing harm to others, particularly in the case of getting benefit for oneself and causing harm to others. Those who cause the detriment should be made liable. This may cause different perception in regards to “artificial” and “natural” exposure. 9. Radon is discussed relatively widely (some 5 pages) but unfortunately more or less solely as an existing exposure situation. Prevention measures – and the possibilities of regulating them – are more or less neglected, even though a lot could be achieved. The ICRP should revisit its thinking (i.e. to put much more emphasis on prevention) bearing in mind the facts that • Despite that the source itself is natural, the exposure is caused purely and solely by human activity. • The exposure is a result of flawed design and bad construction work. • The problem has been recognised already for almost 30 years. During this time, vast amount of houses have been built – and are continuously being built. Already a fair amount of today’s radon problems are associated with houses built during the time we already knew that the problem exists (and were trying to solve the problem by means of intervention). It has been a known fact for a long time that if you build a house at certain areas without taking precautions, you are likely have high radon concentrations. Just like the fact that if you build a house in cold climate area, you will end up with a cold house if you don’t take precautions i.e. design and put some insulation in the structures. At warm climate areas you will end up with a baking house if you don’t place an air conditioner. The ICRP should consider recommendation on how indoor radon could be regulated in an effective way without taking public exposure to radon into the regime of traditional radiation practices. The traditional ways of authorisation etc. would not be the best option. The most effective ways to avoid high radon concentrations in indoor air are construction technological. 10. The extraordinary example given in par (60) is an interesting comparison of different situations but equating the discharge of patients to clearance is perhaps not the best approach. A major difference is that the discharged patient is still under some radiation protection requirements (he or she has been provided with introductions on how to minimize other family members’ exposures etc.) and the destination of the radionuclides (the part of them that is not taken care by physical decay) is known i.e. the sewage system. In case of clearance, there are no such further requirements on the source nor is its destination known. On this basis, leaving the hospital can be considered as part of the practice which also includes some authorised releases to the sewage system. We propose that this example, even though it is a very interesting one i.e. in comparing the amounts of radionuclides involved, could be deleted from this document. 11. Paragraph (101). Some EU countries use lower values in the equation (based on an EC recommendation). However, the values given here could also be appropriate for most building materials provided that a strong reservation is put on the case were essentially only one major material is used (e.g. block of flats made of concrete). In such cases, the values must be lowered by a factor of three in order to keep the doses below 1 mSv. In all other practical cases, where different materials are mixed (e.g. concrete floor, walls of brick, wooden ceiling or something similar) it is only in very few cases where 1 mSv would be exceeded even if some of the materials (e.g. the walls) would be at these higher levels. Thus, these values could be accepted but with some strong reservation on the extreme case of using essentially only one material like the concrete. Some further minor observations 1. The terminology in the document is somewhere inconsistent and somewhere even confusing. The terms used in RP 06 regarding the exposure situations (planned, emergency and existing exposure situation) should be used. The lengthy discussion about practices/prospective exposure and intervention in Section 2.3. is especially confusing. Some other examples on unfortunate terminology: The “ambient air” in the context of radon exposure. Would it not be more feasible to indicate clearly whether it is discussed on outdoor air or the air in dwellings and work places? A similar type of disturbing wording is exposure for cosmic radiation “above the ground level” (i) and (135) and “above the earth surface” (85). Would it not be more unambiguous to use the wording “at ground level” when the issue is not related to air-crew or space travellers. 2. Regarding the air-crew (paragraphs (84) - (88)), there is no reason to apply exclusion or generic exemption to their exposure. It’s totally amenable to control and regulate, as recommended in both ICRP 60 and ICRP 75. 3. The term “competent authority” is used in several places through out the document. It is not defined and in some places it is very unclear whether it means “the regulator” or something broader i.e. combination of “the legislator” and “the regulator”. (Some of the contexts suggest the latter but the word itself resembles more the first. The “competent authority” should be defined or replaced by the defined words “legislator” and “regulator” through out the document. 4. Par (67) starts with the words “The report uses…”. Which is the report this is referring to? 5. Par (98) associates granite with high K-40 concentrations. It is true that granites often have also slightly elevated potassium concentrations but usually this not a significant issue. However, granites do often contain significant concentrations of uranium and sometimes also thorium. So, in this example it would be better to associate granite with uranium (and thorium) and not with potassium. 6. Paragraph (27) states that the average global background dose is 2.4 mSv/a. This is wrong as the value includes exposures from indoor radon (which is normally not considered as background). Please replace the “background” with some other wording or add the radon i.e. “from background and radon….” 7. The lower-bound values of action levels for radon in dwellings and workplaces, 200 Bq/m3 and 500 Bq/m3 should not be considered as de facto exemption levels. Exemption is related to either triviality of dose or on unwarranted (unjustified or unnecessary) control. The related dose is about 3 mSv and control, especially the preventive control when building a house is in most cases both justified and necessary. As discussed in our generic comment no. 8, building a house in radon prone area should actually be regarded as a planned exposure situation. 8. The use of Codex Alimentarius values as generic exemption levels is taking the values out of their context. The existing values and those in the current draft were only designed to allow international trade after a radiological or nuclear accident or an illegal act. The existing guidelines deal with a time of one year after a nuclear accident only. The draft guidelines were prepared under certain assumptions on the exposure situation e.g. that through international trade less than 10 % of an individual’s food would be contaminated during the first year and the fraction would be much lower in later years. These assumptions are not generally valid to define exemption values from any exposure situation. It is also assumed in the discussion of the draft Codex guidelines that actions are taken to reduce contamination levels of food. 9. In the discussion of the assumption of no threshold of risk in paragraph (12) there is an astonishing statement. It could not be the position of the Commission that incremental increases of doses only above the background, whatever it happens to be, are assumed to increase the likelihood of cancer and hereditary effects!