|COMMENTS OF THE “SPANISH RADIATION PROTECTION SOCIETY” TO THE DRAFT ICRP RECOMMENDATIONS (ICRP 05) (November 2004)
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.