|2005 Recommendations – draft for consultation
This is a response on behalf of UK Government Departments and Regulatory Agencies. Our overall views on the draft proposals are set out in this letter. More detailed comments from individual Government organisations are set out in the attached annexes. I understand that some may also send you their comments direct, for instance the Scottish Environment Protection Agency has already done so.
First, we are grateful for the opportunity to have an input at this stage, and we recognise the effort made by the ICRP to consult widely on these proposals. We welcome the intention to consolidate the previous advice issued by ICRP and, in particular, the retention of the basic dose limits from ICRP 60. However, we also note that the foundation documents, on which this draft is based, have yet to be finalised. It is therefore difficult to comment in full on the draft at this stage. We consider that another consultation is necessary on a revised draft of the Recommendations, following on from the production of the supporting documentation and the results of consultations on them.
We consider that it is important that the Recommendations should be clear and coherent when compared against existing recommendations in ICRP 60, and provide practical guidance. At present we feel that the draft lacks clarity – for example a cross reference to ICRP 60 and where the main changes have been made would have been very useful, together with an indication of what remains unchanged. As a result it is unclear when the document is providing clarification of existing ICRP recommendations and when it is providing new recommendations. In any case, the document would be more easily understood if it were produced on a stand-alone basis.
The document would be better structured, if it were based on the ICRP’s radiological protection principles – justification, optimisation, limitation - with detailed technical material placed in annexes. We are also concerned that the ALARA concept is not given the importance it is due; the concept has been found in the UK to be a major driver in reducing doses to workers and members of the public. Over emphasis on cost benefit analyses has not been found to be an issue for us.
We also have concerns about the emphasis that the draft recommendations place on the future use of dose constraints. The recommended dose constraints seem to be the same as the existing dose limits. This has the potential to cause confusion and is less clear than previously. This section needs to be expanded to deal with risks, and not just multiples of natural background, associated with the different levels of dose, how such values are derived and what the implication is for the setting of dose constraints.
Finally, we have concerns about introducing the concept of protection of non-human species in this document. We recognise that the ICRP want to publicise its proposals to consider this issue in detail, but we are not convinced that this has a place in a document that purports to set out the ICRP’s technical recommendations. Furthermore, if left in this document it may be widely seen as casting doubts on the long-held principle that if one protects man then one protects other species.
Specific comments on the text are attached in Annexes 1 – 7 from the following Government bodies:
Annex 1 Health & Safety Executive
Annex 2 Department for Environment & Rural Affairs
Annex 3 Environment Agency
Annex 4 Department of Health
Annex 5 Ministry of Defence
Annex 6 Department for Transport
Annex 7 Food Standards Agency
Annex 8 Department of Environment, Northern Ireland
Annex 1 Health & Safety Executive
We would support the general points made in the covering note, in particular, that further consultation is necessary once the foundation documents are available.
The present system of radiation protection based on justification, optimisation and limitation works well. The ALARA concept has led to a significant fall in radiation exposures and is well understood by those in the occupational field. We are concerned that the current draft could deflect attention from this proven concept.
We are also concerned at the increased emphasis on dose constraints – from an occupational perspective dose constraints have not been particularly effective in practical radiation protection terms and we are not convinced by the proposal to increase the number of such constraints.
We do not fully understand the thinking behind the proposed use of the term ‘radiation weighted dose’. We recognise that many people have confused dose equivalent with equivalent dose, but to abandon their use in favour of a new quantity (which has the same definition as equivalent dose) could lead to much additional confusion.
Our specific comments are as follows:
Paragraph 94 – we are not convinced that the introduction of the gray-equivalent unit is necessary.
Paragraph 133 - our view is that the ALARA concept provides the most fundamental level of protection.
Paragraph 145 – this paragraph may need some further work to clarify its intentions. As drafted it is unclear.
Paragraph 156 – in occupational terms the main driver in the reduction of doses has been the ALARA concept.
Paragraph 161 – clarification of ‘practices that have not been judged to be frivolous’ is necessary. Does this mean practices that are unjustified?
Paragraph 164, second bullet point – this causes us concern in that it could be interpreted as removing the need for the ALARA approach. Clarification is sought.
Paragraph 173 – we are not convinced that the use of age-averaged effective dose coefficients and age-averaged habit data is appropriate.
Paragraph 189 – this is the approach that we have adopted in the UK for many years now.
Paragraph 191 – we have found that employers have not needed to use dose constraints as a tool to help decide on their level of protection.
Section 7.2 – it would be helpful to include an example of how the ‘dose matrix’ concept would be applied, or is this to be included in the foundation document that is currently in preparation?
Paragraph 201 – this paragraph needs some further work to make it easily understood.
Section 9 – we are not clear as to the intent of this section. It contains no recommendations at present.
Section 10 – we are not convinced that the proposed increase in the use of dose constraints is necessary. We are concerned that this proposal could lead to the radiation protection system becoming too complex.
Annex 2 Department for Environment & Rural Affairs
First, I believe that it would be most helpful to the reader if the material was constructed as a free-standing document (rather than one that presumed knowledge of previous ICRP documents). The main text should set out the structure of ICRP’s radiological protection principles in a complete and easily understandable way. Detailed technical material would be better placed in annexes. This is not the way that the current draft is structured. For example, there is no presentation or explanation of the basic protection principles of justification, optimisation and limitation.
It would also be helpful for the reader to be provided with a summary of the main changes since ICRP 60. Also an indication of what remains essentially unchanged.
It seems rather unscientific for the ICRP to consider doses solely in terms of multiples of (a widely variable) natural background without any associated consideration of risk.
ICRP should make it clear whether there is any level of exposure below which it can be taken as inappropriate to see further dose reduction. Is this how they see the 10ì Sv/year dose figure? If so, this should be clearly stated. Such a lower limit for optimisation would not seem to be inappropriate given the wide variation in natural background levels.
I have considerable problems with, and objection to, the newly proposed, activity-based, exclusion levels. To my mind, ICRP’s role is to define acceptable radiation dose levels, and they have no need or justification to go beyond this. Exclusion levels for their radiological protection regime could equally well be expressed in terms of dose.
As it is, the way they have sought to go beyond this to arrive at activity-based levels is unhelpful, potentially misleading, and demonstrates that the ICRP itself does not have the necessary competence in this area.
The relationship of an acceptable dose – ICRP’s main concern – to activity levels depends on the specific scenario in which the dose is incurred and the radionuclides involved. That is, it is likely to be circumstance specific. For the ICRP to go beyond dose in the manner they have does not acknowledge this reality, and is both unnecessary and unhelpful.
It is one matter to set radon action levels, for a situation involving a specific source of radioactivity in an exposure situation that can be relatively well defined. It is quite another to set a single activity-based exclusion level for the vast range of circumstances and exposure situations that can apply in the wider world.
For the ICRP merely to pick values out of the literature and then to quote the minimum figure encountered fails to reflect this complexity, and suggests their lack of competence in this area.
In addition, the way in which the difference between exclusion (from the ICRP regime) and exemption (because of the circumstances in which radiation exposure is incurred) is not well explained in section 2.3, paragraphs 24-26, of the draft recommendations. We are already facing Ministerial correspondence suggesting that the SoLA Exemption Order level of 0.4 Bq/g will need to be reduced in light of the ICRP’s draft recommendations. This is not of course the case, but it does emphasise the need for accurate presentation by the ICRP.
A key point is that there appears there is nothing in the latest ICRP findings to suggest that the mortality or hereditary effects of radiation have been underestimated in the past. If anything, it appears that they have been somewhat overestimated. Hence, it would seem that the findings themselves provide no case for tightening regulatory controls from those from ICRP 60. If this is indeed the case it would be a key point for ICRP to state clearly in their recommendations.
Annex 3 Environment Agency
1. The Environment Agency would be in favour of the ICRP recommendations being self-standing such that all recommendations are in the single document, rather than reference to previous publications.
2. A cross-reference to ICRP 60 and where changes have been made would be extremely useful for regulators and other practitioners. Specifically, it would be helpful to have a matrix showing the relationship between the proposed new recommendations and the old recommendations and a reverse matrix showing the reverse relationship. This would help make things clear. Matrices of this kind are sometimes used in international standards such as ISO, to provide clarity.
3. It is not clear whether the concept of intervention has now been largely dropped in these recommendations.
4. The document appears to say very little about new sources. The document defines (at para 20-22):
Emergencies:- unexpected situations requiring urgent action.
Existing controllable exposures (past accidents, past practices & natural exposure):-sources that can be controlled only by action to modify the pathways of exposure.
Normal situations defined as ‘everyday situations’
However, new sources are not mentioned at this point and there appears to be no term for them. It seems desirable that they should be clearly identified and defined. We suggest that a term ‘new controllable exposures’ could fit well with ‘existing controllable exposures.’
5. Paragraph 53 states ‘The averaging of doses for defining quantities in radiation protection is a widely accepted approach.’ However, it might be helpful to provide some text that explains or reiterates how the use of the quantity ‘effective dose’ and effective dose constraints and limits provide sufficient protection of organs and even cells. It is a difficult concept to explain and there some pressure groups have been undermining the concept of averaging of doses over organs and the whole body.
Radiation weighting factor – Tritium
6. Will ICRP be taking account of recent studies of tritiated water and organically bound tritium which indicate an increase in the dose coefficients for these chemical forms of tritium of a factor of up to about two?
7. More guidance on defining a critical group would be welcome. In particular, guidance on the homogeneity of habits and doses would be useful and whether there needs to be homogeneity in both.
8. It is noted that as well as defining a wider range of maximum dose constraints, the existing dose limits in ICRP Publication 60 also apply. This has the potential to cause some confusion as the public dose limits and worker dose limits are numerically the same as the maximum dose constraints, although some averaging is allowed for in the ICRP recommendations. It would be clearer to reproduce limits in the recommendations rather than cross-referring to ICRP Publication 60.
9. It is perhaps surprising that maximum source dose constraints are not lower than limits given possible other sources contributing to exposure. It is noted that national authorities may set lower constraints and a value of the public dose constraint of 0.3 mSv/y may be used for multiple sources. Para 185 states that constraints under normal conditions will be more restrictive than limits, but this is not entirely obviously true.
10. There is still a case for a collective dose triviality level of 1 manSv/y along with the 0.01 mSv/y constraint, given the linear no threshold assumption.
11. Table S1 is rather unclear about how the maximum constraints apply to workers and the public. It is not clear, for example, whether the constraint of 20 mSv/y applies to the public who are comforting and caring for patients, or to health workers doing the same, or to both. It may be better to divide the table into columns to show how the dose constraints apply to each group - otherwise there are many opportunities for misinterpretation. A suggested new format is as follows:
Possible re-formatting of Table S1. (Maximum dose constraints recommended for workers and members of the public from single dominant sources for all types of exposure situations that can be controlled).
Maximum General considerations Situation to which it applies
constraint Occupational Public
>100 Saving a life or preventing catastrophic circumstances or serious injury
100 No individual or societal In emergency In emergency situations:-
benefit from levels of situations. evacuation & relocation
individual exposure above Controllable
this constraint existing exposures.
20 Direct or indirect benefit for Emergencies. Emergencies: use of
exposed Individuals who countermeasures
receive information and training, Controllable existing such as sheltering,
and monitoring or assessment. exposures iodine prophylaxis
Patient comforters and Patient comforters and
New sources under
1 For situations having societal ??? Existing controllable
benefit, but without individual exposures
directbenefit, and there is no
information, no training, and no New sources under
individual assessment for the normal situations??
exposed individuals in normal
0.01 Minimum value of any constraint N/A New sources under normal
NB - a paper copy of this table will also be submitted for clarity.
12. More advice on handling uncertainty and variability in dose assessments would be welcome. The Environment Agency considers that deterministic assessments of critical group doses which are sufficiently cautious to provide confidence that dose limits will not be exceeded are most appropriate for ensuring compliance with constraints and limits. These assessments may make some assessment of uncertainty to ensure that the assessment is not tending towards optimism, but also is not pessimistic by more than an order of magnitude.
13. The recent reports of the UK CERRIE and COMARE committees (COMARE 9th report - http://www.comare.org.uk/comare_docs.htm) should be considered by ICRP and consideration given to providing information on the uncertainties in dose coefficients.
14. COMARE have recommended that the uncertainties in dose coefficients should be factored into calculations of dose to the public. They have suggested that a value representing a central estimate of the dose coefficient should be used, and a range on either side of the central estimate should be stated. ICRP should consider publishing dose coefficients in this form in future.
15. It would also be helpful if ICRP considered a further issue about “central estimates” of dose coefficients which are published in the scientific literature. It is sometimes unclear whether these are objective central values, or whether judgements about the data used in the calculations may have led to the inclusion of conservatism – such that the stated values will not be true central estimates.
16. We support the concept of a dose matrix for collective dose. This seems a sensible means to disaggregate low doses to large population groups for which a different weight may be applied from higher doses to smaller groups of the population.
17. The Environment Agency strongly prefers activity based exclusion levels to be defined in European or national legislation, rather than by ICRP.
18. The proposed exclusion levels differ in some cases from those proposed in the Codex on foodstuffs and values recently adopted by IAEA. This needs to be resolved.
19. If exclusion levels are proposed by ICRP, then a separate exclusion limit should be provided for tritium, given its low dose coefficient.
Protection of non-human species
20. Consideration of non-human species by ICRP is welcomed.
21. Need to be clear whether protecting ecosystems/habitats, species populations or individual organisms.
22. It is assumed, but not clear, whether ICRP intend to develop dose rates per unit environmental concentration for reference organisms. This would be most useful for environmental regulators. Similarly, it is assumed that dose rate constraints will be developed for each reference organism, in a similar manner to the maximum source dose constraints.
23. Guidance on how to undertake assessment for specific species based on the reference organisms would be valuable. There is a need for assessment data for a range of species – ie wider than a relatively short list of reference animals and plants. Assessments may have to be quite specific in some circumstances, to meet the requirements of national and international legislation.
ANNEX 4 Department of Health
ICRP RECOMMENDATIONS 2005
Medical Exposures and Occupational Exposures resulting from Medical Exposures
Para 144 and 174
The Commission has provided some clarity in its thinking behind the uses of dose limits and dose constraints, the latter relating to single sources.
Paragraph 144 refers to the identification of sources and the application of constraints to each of these sources.
Paragraph 174 refers to the use of the term “single source” in a broad sense. It suggests that x-ray equipment in a hospital should be considered as a single source. This is to be welcomed as long as this includes all x-ray sources, including CT etc, that might be used by an individual in undertaking their function ie the institutions radiology department is considered as a single source. This would simplify matters for radiologists, radiographers etc.
The situation may be more complex when considering some groups of hospital staff who will work with a variety of sources of ionising radiation in a number of departments within an institution. Physicists may be involved with sealed and unsealed radioactive sources, diagnostic and therapeutic beams etc, within a single institution. It is unlikely that personal monitoring will be available for each of these sources. Is it intended that dose constraints are developed for each of these different types of sources? Further guidance may be necessary for such cases.
Paras 216 – 219
The Commission has identified two levels of justification – generic and individual.
Paragraph 216 makes no comment on whether both should be applied for all exposures. This contrast with ICRP 73 which states (para 44) that no additional justification is required for simple diagnostic procedures, if justified generically, beyond checking that the required information is not already available.
Paragraph 217 is somewhat confused and the use of the term “procedure” is not clear. The first sentence suggests the term relates to a medical exposure, but if this is the case, then this sentence relates to optimisation rather than justification. The second sentence also seems to relate to optimisation issues for therapy but reverts to justification issues for diagnosis.
Paragraph 219 picks up on the theme of paragraph 216 by stating that generic justification may not be sufficient for complex diagnostic or therapy procedures. This implies that generic justification alone is sufficient for simple diagnostic procedures but this is not stated as such.
It should be noted that no attempt has been made to define simple or complex procedures and that interventional procedures and other guiding or planning procedures are neither diagnostic or therapeutic and therefore may not be included within this section of the recommendations.
This approach should be reviewed within the context of the conduct of medicine and legally binding documents such as the EC Medical Exposure Directive 97/43/Euratom.
The Hippocratic Oath has as its first principle, “first do no harm” and implies that detriment, a key part of the justification process, should be assessed in each case. In practice all medical interventions, not only those involving ionising radiation, require an individual assessment and justification of the intervention, and while there is a role for generic justification, guidelines or protocols, these must be actively applied in each individual case. This can be considered as individual justification.
It may also be useful to consider the EC Medical Exposure. Article 3.1(b) states clearly that all individual medical exposures shall be justified in advance taking into account the specific objectives of the exposure and the characteristics of the individual. The Directive does not use the term generic justification, but does refer to a type of practice being justified in general. It is our understanding that this relates to justification at a far more general level than the use of generic justification in the ICRP recommendations (the example in paragraph 216 relates to a specific examination, a chest radiograph).
These paragraphs would benefit from further drafting. The Department of Health would favour the approach taken under the Medical Exposure Directive which requires justification for each medical exposure. While generic justification guidelines might be developed as a practical tool, they should not remove the need for individual justification. Such guidelines should be recognised as simply that. In some cases, such guidelines may not apply and the medical exposure indicated in guidelines might not be justified. Similarly, it should be acknowledged that specific medical exposures may be appropriate for individual patients, even if not identified as such under a generic approach.
Annex 5 Ministry of Defence
The United Kingdom Ministry of Defence (MOD) has reviewed the ICRP recommendations and have the following comments to make:
Summary of the recommendations
1. The short summary of the main proposals contained in the document is welcomed.
Chapter 1 - Introduction
2. It is unclear whether the new ICRP recommendations are to replace the ICRP 60 recommendations in their entirety. The new recommendations should make this clear. If some parts of ICRP 60 are to remain extant, this should be specified in the document.
3. This document does not have the clarity of earlier ICRP documents. The scientific concepts e.g. the use of constraints are not clearly explained and some of the wording is quite ambiguous. We would suggest that the wording of the document be reviewed.
Chapter 2 - The aim and scope of the Commission’s recommendations
4. It is understood that foundation documents are being drawn up on a series of topics to underpin the ICRP recommendations. These include the representative individual, biological and epidemiological information on health risks from ionising radiation and dosimetric quantities. As some of these documents are not going to be available until after the proposed closure date of this consultation it is recommended that this consultation be extended into 2005, or a new consultation undertaken so that the whole package of documents can be considered in their totality.
Chapter 3 - Quantities used in radiological protection
5. The replacement of the name of the quantity equivalent dose by radiation weighted dose is helpful as it better describes the quantity. The need for a new unit for radiation weighted dose is questioned. Radiation units are at best difficult to comprehend and explain to workforces, to members of the general public and emergency services. Therefore we believe that a new additional unit is considered unnecessary and should not be introduced.
Chapter 4 – Biological aspects of radiological protection
6. MOD welcomes the revision of the risk estimates and note that there is little change to the values that were contained in ICRP 60. This provides us with greater confidence in these values.
Chapters 5 - The general system of protection and Chapter 7 - The optimisation of protection
7. ALARA, supported by dose limits, has been key to reducing radiation exposure over the last 20 years. In view of its continued success, it is recommended that this concept should not only be retained but to have the same prominence as in the past. There is a danger that ALARA will be undermined by the increased emphasis on source related constraints.
8. The role of constraints should be made clearer. There is a danger that they could become dose limits or pseudo dose limits. ICRP should state in the publication that this is not their intention. Their function should be clearly defined in the draft ICRP recommendations. It is suggested that the use of constraints should be the subject of a foundation document to support the new recommendations, and it may be useful to have some examples to describe how they would operate. We would suggest that constraints should continue to have a similar role as stated in ICRP publication 60.
Chapter 6 – The Commission’s required levels of protection for individuals
9. The constraint values given are termed maximum constraints but it is believed that it is acceptable for a proportion of workers to exceed these values. It is suggested that the term maximum be removed. Furthermore, the lower value of 0.01 mSv does not fit into this matrix and should be deleted. The draft recommendations do not make clear whether constraints applicable to emergency intervention (eg evacuation of public – Table 7) relate to the total dose likely to be received, or dose which can be averted. This should be clarified.
10. MOD notes that the radiation dose limits remain unchanged. This will deliver a longer period of stability. However, MOD like most other organisations in UK has reduced the doses for its workforce well below these values.
Chapter 7 -The optimisation of protection
11. MOD welcomes the statement made by ICRP that “the integral of large exposures over large populations, large geographic areas and over large periods of time is generally not a useful tool for decision aiding because this may aggregate information excessively”. We strongly support this view and hope that ICRP will carry this statement into the final document. We look forward to seeing the foundation document being drafted by ICRP Committee 4 on the principles and methods to implement optimisation of protection.
Chapter 8 – Exclusion of sources from the scope of the recommendations
12. A late inclusion into the ICRP draft recommendations has been the exclusion of sources from the scope of the recommendations. ICRP has in the past gone to significant lengths to show that the effects of radiation are the same for both artificial and naturally occurring radiations of the same. Yet when considering exclusion of sources from the scope of the recommendations it uses figures of 0.01 mSv for artificial radionuclides but for naturally occurring substances of 0.2 mSv. This clearly conveys the wrong message and it would be best if this entire section of the recommendations is removed.
13. The ICRP approach to exclusion levels, whereby in the case of artificial radionuclides the lowest available figure is taken for exclusion, is considered by the Ministry of Defence to be inconsistent and unacceptable and we would recommend that the figures are removed from the publication. It does not distinguish between a lump of concrete or a steel pipe or foodstuffs. Levels of 0.01 Bq/g alpha and 0.1 Bq/g beta if adopted by national authorities and incorporated into legislation would lead to materials currently considered to be non-radioactive under national regulations suddenly being considered to be radioactive and would require special arrangements for their disposal. It would also raise the question of historic liabilities. This would lead to excessive regulation. We consider that these exclusion figures, if adopted, have the potential to significantly damage the credibility of the ICRP.
14. If this chapter should survive it is recommended that ICRP clearly define in the publication the meaning of exclusion, exemption and clearance levels.
Chapter 11 – The protection of the environment
15. The ICRP proposals in this chapter are intended to “safeguard the environment by reducing the frequency of effect likely to cause early mortality, or reduced reproductive success in animals and plant to a level where they have negligible impact on conservation of species, maintenance of biodiversity or the health and status of natural habitats or communities.” However, ICRP still believes that “the judgement that the standards of environmental control needed to protect man to the degree currently thought desirable will ensure that other human species are not put at risk is correct in general terms.” Researchers have found that the sum effect for the flora and fauna as a result of excluding man from the highly radioactive, restricted zone near to Chernobyl has been overwhelmingly positive in favour of biodiversity and the abundance of individuals. This would suggest that radiation even at these high levels is a lower order effect and that if we wish to protect endangered species and maintain a rich biodiversity, resources would be best expended looking at what changes are required to man’s activities e.g. overfishing, reducing the use of insecticides, rather than expending them upon examining the effects of radiation to show that they are not affecting the reproduction of a species or depleting their population.
16. The concept of developing a reference set of animals and plants is unsatisfactory as it will always be claimed that particular animals or plants do not fit with the reference set. If this is deemed to be case then whole new lines of research will be required and with it significant resources will be expended that could be more effectively used. We believe that the whole concept is flawed and should be rethought.
17. Within the UK, and it is assumed most other developed countries, the levels of radioactive liquid discharges has reduced by orders of magnitudes over the decades often to negligible levels today. We would therefore suggest that ICRP rethink the proposals for the protection of the environment.
Annex 6 Department for Transport
The first comment is that there is a large amount of high quality scientific work behind this new draft. I am impressed at both the amount and quality of background work that is drawn together here. I feel it is a shame that the “non-science” aspects of the recommendations sadly confuse the issue. They are not as well drafted, and one might suggest that this is because this is not an area of expertise for the ICRP. I feel that it may be the case that less would be more for this document.
A key issue relates to the ICRP constitution, in particular item 2.1:
"The Commission is established to advance for the public benefit the science of Radiological Protection, in particular by providing recommendations and guidance on all aspects of radiation protection. In preparing its recommendations, the Commission considers the fundamental principles and quantitative bases upon which appropriate radiation protection measures can be established, while leaving to the various national protection bodies the responsibility of formulating the specific advice, codes of practice, or regulations that are best suited to the needs of their individual countries."
It is important that the recommendations of the ICRP are not seen as regulations, nor should they interfere with the process of generating regulations effectively (perhaps by being too helpful).
ICRP are not a body with a right for input (e.g. from governments or public). Some may see this as an issue, however I feel this is appropriate to the type of learned body. This then means that the experts’ recommendations need to be modified in a more democratic forum to account for social and economic interests where regulations can be drafted.
I believe that to this extent the ICRP recommendations may go too far and suggest possible regulatory approaches in order to be helpful. Examples are as follows:
It is correct for ICRP to set out the principle of exclusion. It is not correct for ICRP to specify the specific exclusion values, this goes beyond their constitution. The suggestion is that DS161 etc should be brought in to ICRP text. There are specific problems here (not least of which is that the values were not considered applicable to transport because the models were not appropriate), in that there is now a circular reference in documents. If IAEA amend their model will ICRP follow with a change in their document, or should it be the other way round? It is essential that the structured flow of recommendations and regulations continue. I see the proper flow as ICRP recommend based on their acknowledged expertise, and IAEA draft regulations taking into account wider issues in a democratic forum.
With regulation you want to place the emphasis where the greatest potential for harm exists. Doing otherwise has the potential to compromise safety. Radionuclide based exclusion values are very low levels and go in to incredible detail. In my view this could place too great an emphasis at the safer end of the regulatory spectrum.
There may be more appropriate ways of regulating this type of material - radioactive material does not appear out of nowhere. It may be more practical to deal with exclusion on the basis of the activities carried out than on specific radionuclide limits. Take the example of a wooden desk - should we measure the radionuclide content of all wooden desks, or should we assess the effect of ground contamination and suggest that where contamination of the ground around trees exceeds a set level then the wood produced from those trees should be examined with respect to those particular radionuclides, and the projected use of the wood? These are two very different approaches to exclusion. One looks at the content of material, the other looks at the process of adding radioactive material to objects (and thus I would argue concentrates resources where appropriate). The route taken by ICRP is so specific that it excludes one of these options.
Regulation of practices.
How you formulate regulations is key to making them work. The issue for ICRP is the exposure of persons. How we set about controlling this exposure is a regulatory issue. For example it may be appropriate to deal with something called a "practice" in many cases. In other cases it may not. Transport in particular is affected by this. Where accumulations of sources from various consignors are carried by one conveyance the concept of regulating individual practices becomes complex and may not offer the most effective protection to persons (both consignors and carriers could be considered as practices, and both could be exposing the same people at the same time from the same source). This is particularly complex for international transport. When you consider aspects such as justification and dose constraints for international transport within national legislation you realise that the formulation of the ICRP recommendations relating to practices causes problems (consider exposures in one state and benefits in another - how do you regulate international practices nationally?). ICRP should be concerned with the exposures to workers and the public, but not how to put this into specific legislation.
Little is said of this in the new recommendations. There is a specific problem with this in that ICRP are primarily a radiological protection body, and one needs to question whether justification is a radiological issue or a general safety issue. We would not want people driven from the use of radioactive material to a more harmful toxic material because justification is applied to the radioactive material but not the toxic material. I believe ICRP have suggested this in the past, but formally I question whether they should include justification (as set out) as part of their recommendations, or simply state that there is a general assumption that the principle is applied. Again there are particular problems in how to draft legislation nationally because of the way these recommendations are formulated. I am not suggesting that the principle is wrong - but that the principle is expressed in a way which limits regulatory texts. We need to prevent the use of radioactive material where there is no benefit to society, how we go about this needs careful consideration. I would also suggest that this area is encroaching on areas which ICRP should not deal with - but should be left to bodies such as IAEA.
This seems to be specific legislation in many instances. There are many aspects of dose constraints that need wider airing than is given in ICRP. There was an excellent TECDOC put together by IAEA in draft form dealing with dose constraints and how to establish them in different situations, which would seem to form a good basis for discussion. This would seem to be the way to deal with this type of issue - the specifics ought to be dealt with away from the ICRP, the general principles having been established by ICRP. For ICRP to give a bland order of magnitude statement is not appropriate (there are social and economic issues that need to be considered).
The draft is not comprehensive enough and is also too specific, going beyond the limits set in the ICRP constitution. I applaud the ICRP for some very good quality work in providing advice on how to determine the harm caused by radiation and the proposed simplification of terms. There is a lot of good quality work in this document. I think the non-human biota work is also a good start (however see the specific comments below).
I would welcome a more concise and more comprehensive statement of protection policies. I would also welcome the inclusion in a covering statement the details of how ICRP see their recommendations being converted into regulations - do they see IAEA as having a key part? I have no argument with the basic principles set out by ICRP, but I would contest several instances where the recommendations go beyond basic principles to specific means of applying them.
Non-human biota - specific comment.
I question the general approach of consideration of a species. Exposure of animals in aircraft holds is becoming an important issue – in this case the principle of protection of humans does not apply. Medical products are being refused carriage because animals are on board. As a result I think it is a good step to start exploring this issue.
In the extreme, according to the proposed approach (i.e taking the concept to the limit), we could argue that irrespective of the exposure (even if it would be certainly fatal) this is acceptable because it will not affect the species (there would be few animals involved). This would be strange - because the segregation decision would then be based on the rarity of that particular animal, not on the potential exposure. It would also permit radiation burns to animals in transit. The measurement of radiation levels is easier than the measurement of rarity.
Looking at the effect on the species - how would you cope with the Tse Tse fly irradiation programme?
What about medical exposure of animals (and carers/workers)?
Perhaps this needs consideration in a wider forum than ICRP to develop the principles?
Annex 7 Food Standards Agency, Emergency Planning, Radiation and Incidents Division
The Emergency Planning, Radiation and Incidents Division of the Food Standards Agency welcomes the opportunity to comment on the draft ICRP 2005 Recommendations. We have a number of comments on the draft Recommendations. These are summarised below:
1. As currently drafted the Recommendations lack clarity as to what parts of previous recommendations are still applicable. It would be helpful if the 2005 Recommendations restated the principles of the Commission, gave a clear summary of the status of previous guidance, and were written as a standalone document.
2. Section 6.3.1
We welcome the Commissions retention of the critical group concept. We understand that that the report on the Representative Individual for the Purpose of Radiation Protection of the Public is intended to give more detailed guidance on the application of the concept but is not yet available. We look forward to the opportunity to comment on a draft of this report in due course.
3. Section 6.3.1
We suggest that guidance on whether the homogeneity criteria for a critical group should be applied to the habits of the group or to the doses received by members of the group would be a helpful addition. Experience has shown that it is possible for members of the public with different habits to receive comparable exposure from the same source.
4. Section 6.1
Radioactivity is only one of the substances in food that can cause a detriment to consumers. The comparison of the risks that different substances in food represent, if they are present at the relevant limit, is facilitated if the limits are derived based on risk. Derivation of the limits and constraints for the exposure to radiation by comparison with background levels makes this comparison between substances more difficult. Comparisons between different substances will be less transparent to members of the public who have little knowledge of risks from exposure to background radiation.
5. Section 6.2
It would be helpful to clarify whether the dose for exposure of members of the public, which is compared to the constraint for a source, includes exposure caused by past practices connected to the source.
6. Paragraph 54
As currently drafted the restrictions on the use of effective dose i.e. that it should not be used for retrospective assessment of stochastic risks is, in our view, too prescriptive. In practice, interpretation of the results of surveillance programmes to demonstrate compliance with dose constraints requires the use of effective dose.
7. Chapter 8
It would be helpful to clarify in the Recommendations that national and international authorities could set exemption levels that are higher than the proposed exclusion levels. It would also be helpful if the distinction between the concepts of exclusion and exemption was explained in the Recommendations.
8. Chapter 8
In some cases the proposed exclusion levels are higher than the levels proposed by Codex Alimentarius for limiting radionuclide concentrations in foods in international trade. Similarly in some cases the proposed exclusion levels are higher than the exemption levels specified by the IAEA in Safety Guide RS-G-1.7. The interrelationship of these levels needs to be resolved and the methods used to derive the recommended levels should be described.
Annex 8 Department of Environment, Northern Ireland – Environment and Heritage Service, Industrial Pollution & Radiochemical Inspectorate
COMMENTS ON ICRP RECOMMENDATIONS
· The new document should be stand-alone with cross references to ICRP 60 – differences should be highlighted in some way.
· The recommendations should make it clear what way the ten micro Sv per annum dose is to be viewed. Is it a level below which further reduction is not required from a protection stand-point.
· Even though much scientific work has still to be done, we welcome the ICRP advice and guidance on non-human species. Will ICRP proceed to develop dose rates/environmental concentrations of radionuclides for reference organisms – this would be very helpful. Guidance on how to extrapolate from reference to specific organisms would also be welcome.
· We do not think it appropriate for ICRP to define activity based exclusion limits. The distinction between exclusion and exemption should be clarified. Differences between the limits quoted and those proposed in the CODEX (food stuffs) and IAEA guidance should be resolved to avoid confusion.
· More guidance is required on defining critical groups – perhaps after the Committee 4 report issues.