|The following comments were aproved by the Nuclear Safety Council last 22 December in the periodical meeting of the Council:
COMMENTS OF THE ”NUCLEAR SAFETY COUNCIL” CONSEJO DE SEGURIDAD NUCLEAR TO THE DRAFT ICRP RECOMMENDATIONS (ICRP 05)
The Nuclear Safety Council fully endorses the comments made by the Spanish Society of Radiological Protection (included in Annex), considering that they represent the opinion of the radiation protection professionals of Spain, including CSN, whose experts have actively participated in the preparation of these comments.
We want, nevertheless, to point out some aspects which CSN believes are of special relevance from a regulatory point of view:
1. The absence of clear identification of the bases in which the new recommendations are sustained, as well as the degree of modification or permanence of the bases that support the current system of radiological protection.
2. The loss of relevancy of the principle of justification, provided that there are areas in which the considerations related to radiation protection have special importance.
3. The degree of discretionality in the application of the recommendations, which implies a great risk of losing the present international harmonization.
4. The application, as a new concept legally binding, of the term “dose constraint“ which can be the origin of misunderstandings.
5. The recommended values of “dose constraints“ which encompass the values previously used for dose limits, action levels and intervention levels. The use of a single term to cover so different concepts can create confusion.
6. The initial intention of not making distinction between practice and intervention. The current System of protection clearly distinguishes them and this distinction facilitates the regulatory requirements and actions. In fact, along the text, the distinction is made to define the criteria to be recommended (§140, §147).
7. The consideration of IAEA Safety Guide RS-G-1.7 taking into account the international consensus that has been built in its development.
8. The need of clarification of the term single source, in order to avoid difficulties and inconsistencies in its practical application.
9. The importance of having a stand alone document for the new Recommendations.
Additionally to the previous ones, following considerations have raised as a consequence of the analysis of the draft recommendations, carried out in this Organism.
1. There is some confusion in the text between what principles are, with respect to criteria. The Commission has in the revised text, the criteria, but not the principles. Section 5 should deal with the principles as stated in ICRP-60 to establish fundamentals and objectives. As the current text does not define them, there are many contradictions and situations not covered (e.g. intervention from accidents, from previous practices…).
2. Clear definitions of terms are needed to understand the applicability of the recommendations (e.g. dose constraints). Additionally some definitions given do not clarify, e.g. (§21) says that normal situations are everyday situations, and new terms are introduced. In consequence, it is suggested that a Glossary of Terms should be developed, in order to ensure coherence in the terms used in this document and consistency with other ICRP publications.
3. Some specific key issues are not dealt with, and there are other issues which require additional clarification or explanation.
• ”Stochastic” effects are referred within the text, but this is not the case for “deterministic” effects which have been replaced with the term “Tissue Reactions”. The use of the term deterministic in the Radiation Protection context is well understood within the profession and the new term could create misunderstandings (cancer could be considered a tissue reaction from the medical point of view) It is encouraged to reconsider this change.
• BAT. ”Best available technology not entailing excessive cost” (§194) is introduced in the document without further explanations.
• Natural radionuclides present in processed materials as well as wastes from practices should be framed in relation to exclusion.
• Potential exposures for waste disposal facilities, due to human intrusion as well as natural events.
4. Optimization introduces measures to reduce doses. The system is intended to be based on the control of sources, without giving its relevance to each of the factors influencing the final dose (pathways, individual, operation, etc). Rewording is needed in some items to consider these other factors (§166).
5. Stakeholders’ involvement requires additional clarification in order to harmonize their role in decision processes.
6. Paragraph 28 indicates that international agreement on a single set of radionuclide-specific levels for exemption would facilitate a consistent regulatory approach worldwide. This paragraph does not take into account the possibility of exemption for radiation generation devices. Therefore it should be completed including the need of achieving international agreement on criteria (in terms of dose rate) for exemption of these devices.
7. Headline of Part 6.3.3 (chapter 6) is “The exposure of women”. Considering that the Commission concluded that there was not reason to distinguish between the two sexes in the control of occupational exposures and that this part deals with the protection at work for women who may be pregnant in order to protect the unborn child, a change of that headline is proposed, naming it “The exposure during pregnancy”
8. The protection of non-human species is introduced and there is a chapter (11) specific for this item. ICRP expects to give recommendations in next future, and in consequence there is not specific advice in here. This fact indicates that it should be convenient to wait for those specific recommendations.
In consequence the reduction of the chapter is proposed, focusing it on Policy aspects.
COMMENTS OF THE “SPANISH RADIATION PROTECTION SOCIETY”
TO THE DRAFT ICRP RECOMMENDATIONS (ICRP 05)
COMMENTS OF THE “SPANISH RADIATION PROTECTION SOCIETY”
TO THE DRAFT ICRP RECOMMENDATIONS (ICRP 05) (November 2004)
A. GENERAL COMMENTS
1. It is essential that the document clearly identify the bases (both the scientific as well as the “operational”) supporting the new recommendations now being offered, as well as the extent to which those bases supporting the radiation protection system recommended to date are maintained or modified.
Likewise, the document should identify, without any shadow of doubt, which recommendations currently in force remain valid and which are changed or simply clarified.
This might be achieved in the “Introduction” to the document, although it would be necessary for the subsequent development of the text to be coherent with it.
2. The text of the document includes an announcement of the subsequent publishing of an appreciable number of additional explanatory documents. Since the starting point in this respect is a basically stable situation as regards the radiation protection system recommended by the ICRP, it would appear to be necessary for the publishing of these documents to take place before (or in combination with) the publishing of the new recommendations.
3. It is necessary for the text to be carefully controlled in order to ensure the coherent use of various terms of great relevance when applying the radiation protection system: “controllable source”; “controllable exposure”; “occupational exposures”; “normal situation exposure”; “practice”; “exclusion”; etc.
In addition, the introduction of new concepts or of new terms for concepts already in existence and widely accepted should be avoided unless absolutely essential.
4. The recommendations now presented include a dual degree of discretion in their application: on the one hand they are less rigid than the current recommendations in various aspects, and on the other they explicitly recognize the existence of wide margins for the users.
The sum of these two characteristics introduce a high risk of losing the excellent degree of harmony achieved and currently existing at international level, which is considered to be an important asset of the radiation protection system and of the role played by the ICRP within it.
5. As a consequence of the comments above it seems reasonable to further reconsider the date now foreseen for the publication of these recommendations. It looks like additional significant efforts should be devoted first in analysing and in ensuring that their publication will bring about the positive effect desired, as well as to resolve consequently many of the difficulties posed by application of the current system.
B. SPECIFIC COMMENTS
1. Subject.- Meaning of the “dose constraint” concept (Summary and Main text)
ICRP.- The term “dose constraint” represents the basic level of protection to be achieved in any type of situation (normal situations, accidents and emergencies), to which is assigned a status equivalent to given limit that may be used (paragraph 137) retrospectively from the regulatory and legal point of view (…exceeding a mandatory constraint may be a statutory offence.)
Comment. This approach differs drastically from the one used in ICRP-60, where “dose constraint” represented simply a reference value (to which no legal standing was assigned), to be used, retrospectively, only in the phase of planning of practices.
The use of one same term to express two concepts as different as these are (source-related legally binding value in RP-2005, and reference value in ICRP-60) may lead to confusion and errors in interpretation.
ICRP should maintain the concept of “dose constraint” as included in ICRP-60 (prospective restriction of dose to be applied in the planning of protection within practices) and use a new term to refer to the “source related legally binding value”
2. Subject.- The principles of protection (Summary).
The Commission required levels of protection for individuals (Main text).
ICRP.- The last sentence of paragraph S7 includes a declaration regarding the definition of the values of the “constraints” at national level, which will not favour international harmonization. This is subsequently repeated in the last sentence of paragraph 163.
Furthermore, both in Table S-1 and later in the text of paragraph 164 and in Table 7, another factor of discrepancy and possibly very negative effects is introduced, when the value of 0.01 mSv/yr is described as being the “Minimum value of any constraint”, when today it is very generally accepted that it is the value below which no additional considerations are necessary from the point of view of radiation protection (beyond the need for “justification”).
Comment. The document should define a recommended value (e.g., 0.3 mSv/yr) to orient the definition of “constraints” at national level, although a certain (minor) margin of discretion might be explicitly recommended.
The document should clearly indicate the meaning assigned to the value of 0.01 mSv/yr, in the same sense as it is generally accepted today.
3. Subject- Optimization of protection (Summary)
The characteristics of the optimization process (Main text).
ICRP.- Paragraphs S11 and 196 introduce and define the process of involvement of the so-called “stakeholders” in the application of the principle of optimization, and it is recognized that the scope of this involvement might vary in different situations.
Comment. With a view to avoiding possible subsequent disturbing effects, it would be advisable for this idea to be developed further and explicitly, both in the Summary and subsequently in the main text, in order to underline the fact that the differences between the various situations of exposure might be essential. We refer to differences between “normal” or “accidental” exposures; exposures of “workers” or the “public”; “planning” of activities or their “performance”, etc. Likewise, the situation might be radically different when decisions of a strategic nature are implied (e.g., the introduction of a new practice or regulatory developments) and when an operating situation is involved (e.g., decisions regarding the specific application of a technique to a patient or whether to use one or another means of personal protection for a specific activity).
4. Subject.- Justification (Main text).
ICRP.- The principle of justification loses relevance when it is considered (paragraph 18) that decision-making in this respect is performed by the governments on the basis of political, social or strategic considerations not directly relating to radiation protection. ICRP considers that radiation protection may play a relevant role in justification only in the case of medical exposure (paragraph 19).
Comment. There are other fields (apart from medical exposure) in which considerations relating to radiation protection might play a determining role as regards justification:
The use of X-rays for legal purposes (immigration control)
The use of X-rays for security purposes (diamond mines)
The re-justification of practices adopted in the past.
The use of radiations in relation to consumer goods
ICRP should maintain the principle of justification (and re-justification) in the same terms as in ICRP-60, even though their use be clarified.
5. Subject.- Exclusion of sources (Summary and main text)
ICRP.- lCRP considers that certain sources give rise to collective doses that are so low as to be legitimately excluded from the recommendations, and as a result establishes activity concentration values that, to all practical intents and purposes, represent the threshold that may be considered radioactive for the purposes of radiation protection.
Comment.This concept is particularly transcendental, for which reason greater attention should be given to explaining it, in particular to clarifying certain aspects relating to its practical application (as is done in the IAEA guideline RS-G-1.7). It is also significant that the levels proposed for artificial radionuclides are not consistent with those established in the aforementioned guideline.
In order to avoid confusion and errors in interpretation, the concept of exclusion (and associated numerical values) should be consistent with what is established in the IAEA guideline RS-G-1.7.
6. Subject.- Practices and interventions (Summary and main text).
ICRP.- The new recommendations do not contemplate the term “intervention”, which had been introduced in the recommendations of ICRP-60, although in one paragraph (192) the term “intervention levels” continues to be used.
Furthermore, in the new recommendations the term “dose constraint” (which in ICRP-60 was applied only to practices) is applicable both to “normal situations” (in other words practices) and to “emergency situations” and “controllable existing situations” (in other words interventions).
Comment. One of the main values of ICRP-60 was that it made a clear distinction between the principles applicable to planned situations (practices) and those applicable to existing situations (interventions). These differences are not so obvious in the new recommendations, as a result of which there might be confusion and errors in interpretation.
The new recommendations should maintain a clear distinction between the radiation protection system applied to practices and that applied to interventions (regardless of the name that might be used in one case or another).
7. Subject.- Coherent use of terms. Practical examples (Summary and main text).
ICRP.- On line 6 of paragraph S20, and also on the penultimate line of paragraph 1, the term “practices” is used in a sense that does not coincide with its definition.
In paragraph 5 the term “interventions” is used in the sense indicated in ICRP60, although it is not defined in this text.
The text of paragraph 24 includes references to “exclusion of sources”, paragraph 25 to “sources and exposures that are not excluded”; 26 to “material that is exempted”; 27 to ”exemption of sources” and 28 to “exemption of sources of exposure”.
The following expressions are used throughout the text of point 8 of the document, in association with the concept of exclusion: “sources”; “values at which artificial radionuclides”; “materials”; “situations”; “values of activity concentrations”; etc.
Comment. The revision of all these texts is considered necessary in order to clarify the use of the different terms used and ensure coherence in such use.
8. Subject.- The definition of a single source (Main Text)
ICRP.- Paragraph 174 establishes that it has not been possible to achieve formal definition of the term and that it should be used in a wide sense in the application of constraints.
Comment. The Commission itself recognizes in the text that difficulties might arise due to the grouping of sources or to the artificial division of a source.
In order to avoid difficulties and inconsistencies, it is proposed that attempts be made to clarify and specify the meaning of the term, for example through the creation of a specific annex debating the term and analyzing examples that might serve as a guideline for practical application.
9. Subject.- The development of a framework for the protection of non-human species (Summary).
The protection of the environment (Main text).
ICRP.- Paragraph S18 indicates that there will be assurance that the protection of humans and of other organisms will be afforded “on the same scientific basis”.
The second sentence in paragraph 246 refers to filling “a conceptual gap”, while the basic idea of the text is that the aim is rather to cover an aspect of the current system that is purely formal or presentational.
Comment. It would appear to be highly doubtful that the system for the protection of non-human species might be developed in the short and medium term “on the same scientific basis”. Furthermore, it would not appear to be necessary, since the aim is for there to be coherence with the framework of the protection system defined for humans. Consequently, it is recommended that the indicated text be corrected.
Furthermore, paragraph 246 includes the recommendation that the term “conceptual” be replaced with “presentational”.
10. Subject.- Values proposed for “dose constraints” (Summary and main text)
ICRP.- Tables S1 and 7 indicate the maximum dose constraint values recommended for workers and members of the public for all types of controllable exposure situations.
Comment. The recommended values included in the table encompass the values previously used for dose limits, action levels and intervention levels. With the previous concepts (practice/intervention), the limits constituted a ceiling that could not legally be exceeded and below which optimization was required. For their part the levels of action/intervention were basic values that required intervention in the event of their being exceeded but below which no actions were necessary. The use of a single term to cover such different concepts might give rise to confusion and problems.
Furthermore, the value of 20 mSv/year is established for existing controllable exposures, using radon as an example, while subsequently, in paragraph (179) the specific value of 10 mSv/year is considered in this same respect.
It is considered essential that the different situations to which each of the values included in the table would be applicable be identified more completely and in greater detail. In particular, it is necessary to clarify the situations of exposure to natural radiation sources, which in the previous recommendations were addressed from the point of view of intervention and were required to be treated separately, unless otherwise determined by the regulatory authority. Likewise, it is necessary to clarify the values applicable to radon and to reconsider the issue of “comfortes”, for which the same maximum value as applicable to occupational exposure is established.
11. Subject- Exclusion and authorization of exposures (Main Text)
ICRP.- In both paragraph (25) and in paragraph (26) the term “authorization” is used in a sense that might collide unnecessarily with regulations already implemented in certain countries.
Comment. It is proposed that the word “authorization” be replaced with the word control in both cases, as well as in the title of section 2.3, such that the concept of authorization be understood as being just one specific type of control.
12. Subject.- Quantities used in radiological protection (Main text).
The induction of cancer and hereditary effects (Main text).
ICRP.- In general, the wording of point 3 of the text (especially points 3.3 and 3.4), and of point 4.2, would appear to contain excessive detail, and their contents certainly clash with the rest of the document as regards the level of detail.
Comment. It is recommended that only the essence of the current content be maintained in the main text and that the rest of the more detailed information be included in an Annex.
13. Subject. Dose constraint values on the basis of natural background (Main text)
ICRP.- The maximum values proposed by ICRP for “dose constraints” are established taking the natural radioactive background value as a reference, excluding the contribution made by radon.
Comment. This approach is highly arguable in the realm of occupational exposure and modifies previous ICRP approaches (publications 26 and 60), in which the values proposed as limits were always based on considerations of risk (for example comparing the occupational risk of work with radiations with that of other industries). The new ICRP approach might not be understood by society in general and might also give the impression of a certain arbitrariness.
Furthermore, the wording of paragraphs 160 and 161 is fairly confusing and might give rise to errors in interpretation.
14. Subject.- The exposure of women (Main Text)
ICRP.- Paragraph 175 indicates as follows: “The Commission considers that this policy will be adequately applied if the mother is exposed, prior to her declaration of pregnancy, under the system of protection recommended by the Commission.
Comment .The policy of the Commission is established in the interests of protection, and the previous recommendations had already eliminated limitation of exposure to the abdomen of women, considering that the basis used for the control of occupational exposure is the same as for men, except in the case of pregnancy.
In view of the above, it is proposed that the aforementioned text be revised as follows: “The Commission considers that this policy will be adequately applied if the mother is protected, prior to her declaration of pregnancy, under the system of protection recommended by the Commission for occupational exposures”.
15. Subject.- Concept of “radiation worker” (Main text)
ICRP.- Paragraph 169 introduces the concept of the “radiation worker” (which was not contemplated in previous recommendations), establishing an apparent link between those considered as being exposed workers and access to the controlled zones.
Comment. Neither the ICRP recommendations nor the international standards had established to date that a worker should be classified as a “radiation worker” merely on the basis of access to the controlled zone. Such classification has always been based on the possibility of the occupational doses received by the worker exceeding a given fraction of the annual dose limit.
It is habitual practice in many countries that members of the public may access the controlled zone as long as the conditions of access ensure that the doses received by such members of the public remain far below the dose limits applicable to them. There would be an important (and negative) impact in these countries if, as a result of the new recommendations, any person accessing the controlled zone had to be classified as an exposed worker.
16. Subject.- Dose limit for the skin (Summary and main text)
ICRP.- The new recommendations indicate that the dose limits established in ICRP-60 continue to be valid.
Comment. The dose limit for the skin established in ICRP-60 (500 mSv averaged over a surface area of 1 cm2) was based on a study performed by the US Nuclear Regulatory Commission, which demonstrated that the initial approach adopted in the first draft of these recommendations (500 mSv averaged over 100 cm2) did not prevent the appearance of deterministic effects in the event of contamination by “hot particles”.
In 2002, the US Nuclear Regulatory Commission reconsidered its previous position, establishing that the dose limit for the skin be averaged over 10 cm2, due to its considering that the average over 1 cm2 was unnecessarily restrictive. It is considered that the ICRP should adopt a similar approach.
17. Subject.- Optimization of protection (Summary)
The characteristics of the optimization process (Main text).
ICRP.- Optimization is maintained as one of the principles of the protection system complementing dose restrictions.
Comment .There is an obvious need to clarify the meaning of the principle of optimization and the way it is applied.
It would be appropriate for the text of this point to provide explanatory and clarifying information, distinguishing the application of this principle in the various situations of exposure:
- Normal vs. emergency or post-accident
- Workers vs. public
- Planning of activities vs. performance of activities
Likewise, it is considered necessary that the definition, consideration and application of the “dose matrix” be clarified and specified in the processes of optimization.
18. Subject.- Limits on effective dose for public exposure (Main Text)
ICRP.- These are included in paragraph (185), the values established in the previous recommendations being maintained.
Comment. From a practical point of view, both the actual significance of the public dose limit and the feasibility of its being controlled continue to be controversial. Following the summary included in paragraph 192 of publication 60, it would be advisable to clarify the real meaning of this limit, explaining the low degree of practical significance that it has and the advisability of not overvaluing such significance, placing the emphasis (in this case in a special manner) non the restrictions associated with individual sources.
19. Subject.- Medical Exposures (Main Text)
ICRP.- Paragraph 215 begins by indicating that “The physicians involved in the processes that irradiate patients should always be trained in the principles of radiological protection”
Comment. The process of irradiating patients includes the intervention not only of the doctor required for diagnosis or therapeutical treatment, but also of other professionals who participate in the protocols and activities required for delivery of the dose, this implying a risk of exposure to ionizing radiations, as well as the implications of their role in protecting the patient.
Consequently, it is proposed that this paragraph be revised, its wording possible beginning as follows: “The physicians as well as the other professionals involved in the processes that irradiate patients should always be trained in the principles of radiological protection”.
Consideration should be given also to the fact that these professionals may play a relevant role in the optimization processes.
20. Subject.- Annex B (B-.1) Introduction.
ICRP.- Paragraph B2 refers to the establishment of “constraints” relating to the “quantities of radionuclides deliberately introduced into the environment”.
Comment. It should be taken into account that in the definitive management of radioactive wastes such introductions are sometimes performed deliberately and to values of activity far in excess of any imaginable “constraint”.
It is suggested that the text be revised in order to avoid direct contradictions with radioactive waste management activities.