Comments on Draft ICRP NORM Document
General Comments:
This publication presents a shift in current philosophical thinking regarding how governments address NORM questions. To date, such questions depended on whether there was material in the process stream that was controllable. At that point, it was possible to bring the practice within the usual scope of radiation controls under a licence with a proportional regulatory approach.
To address NORM questions the way the ICRP is proposing presents a few obvious questions: What is the exact nature of the problem that this advice from the ICRP is trying to solve? How have the traditional ways of addressing NORM matters been a failure to warrant the shift to treating NORM exposure as a form of existing exposure?
For an issue that may or may not be significant, the ICRP seems to be applying particular significance to the principles of equity and justice it states that radiation matters within NORM industries must be considered as a matter of justice and equity (Page 32, Para 134). If doses from some NORM industries can be greater than those from currently regulated planned exposures (Page 32, Para 134), then why wouldn’t any regulator when its determined that such exposures are of a magnitude to warrant regulation, subject such practices to the common platform of regulatory controls for planned exposure situations?
It is generally agreed that there are industries within which there is poor awareness of the potential for NORM. It is also agreed that we are not discussing acute radiological risks with any NORM industry sector. Certainly, engagement with NORM sector industries identified both in this ICRP draft document and in the national guidance document from ARPANSA should at some point be undertaken with a view to getting more of such industries to take a look at their respective processes for potential NORM build up and consider the need for remediation strategies in line with many of the recommendations in this document. Again, however, once NORM “pinch points” have been identified that have controllable amounts of radioactive materials, it makes sense to include such companies within the scope of standard radiation controls. When NORM concentrations are below regulatory control, but the doses warrant control as per the tests in the National Directory and legislation, the ‘inclusion’ power could be used if the respective industry sector or company does not wish to assess and remediate etc.
The implementation of the framework in the way that the ICRP envisages would not only require considerable additional legal powers to deal with NORM pathways that would be currently below the regulatory concern of the Radiation Act but also require the addition of considerable human resources within government to ensure that the framework is satisfied. It may be that the use of the ‘inclusion power’ within the Radiation Act 2005 and identifying relevant NORM sectors would be the fairest and most risk based approach with respect to licensing, compliance assessment, and enforcement.
Specific Comments:
Abstract
Cites the requirement for radon protection in accordance with ICRP 126 “Radiological Protection against Radon Exposure”, which contains this paragraph below:
4.6. Protection of workers against radon in the uranium mining industry
(133) National authorities may decide to manage some occupational exposures to radon as planned exposure situations from the outset. This is typically the case for the uranium mining industry. Factors that influence this choice include the levels of exposure to other sources in the mine, including external exposure to gamma radiation, and inhalation or ingestion of radioactive dusts. The long-lived radioactive dust can be uranium ore during the mining and initial stages of milling, and/or the refined uranium product, often a uranium oxide powder. In addition, there can be potential exposures to other uranium decay series radionuclides, depending upon the process. In uranium mines, radon progeny may be the dominant source of radiation exposure. Protection of workers against exposures to radon in the uranium and thorium mining industries are regarded as being the responsibility of the operating management.
This requirement implies that radon exposure to workers would be treated as part of a planned exposure scenario in the mineral sands sector.
It is also stated in the Abstract that “a reference level for the protection of the public should be selected below a few mSv per year.” Such might be fine in relation to an existing exposure situation. However, from ICRP #126 above, it would be considered that mineral sand mining is indeed a planned practice. Hence the only reference level that can apply must be equal to the public dose limit of 1 mSv per annum.
The Abstract seemingly conveys the impression that NORM matters have been identified as difficult in some way. This identification has resulted in the ICRP seeking ways to circumvent its own radiation protection limitation philosophy by trying to define the planned practices of mining as existing exposure situations. Why would the ICRP be concerned about non-human biota from NORM practices if it accepts members of the public exposed in relation to NORM practices being exposed to a higher level than the currently applicable ICRP public dose limit for planned practices? This approach is difficult to reconcile.
Main Points – Page 5
Interpreting the first dot point:
“Situations involving Naturally Occurring Radioactive Material (NORM) are existing exposure situations except when NORM is used for its radioactive properties.”
This point implies that uranium mining is a planned practice and thorium mining is an existing exposure situation. Hard to reconcile, given that both have been treated to date as planned practices. It is considered that the delineation is inconsistent with respect to the equitable application of radiation controls.
Interpreting the second dot point:
“NORM industrial activities are controllable, and protection is achieved through optimisation using reference levels.”
This point implies that such practices are justified, optimised, but not subject to limits. Why should NORM practices be treated any differently from non-NORM practices? It is considered that the delineation is inconsistent with respect to the equitable application of radiation controls. The definition of NORM (page 41) might be of assistance at this point: “Material containing no significant amounts of radionuclides other than naturally occurring radionuclides, in which the activity concentrations of the naturally occurring radionuclides have been changed by some process and giving rise to enhanced exposure to human and non-human species.”
This definition implies that NORM is naturally radioactive material enhanced by human activity. Some sources of NORM will be below ICRP exemption levels; some will be above. Does the ICRP expect differential treatment of supra-exemption level NORM material from that normally applying to radioactive material generally? That is to say, do they really want to have different dose limits for uranium mining, mineral sand mining, and all other regulated practices? This effectively creates a two tier limitation system by another name.
Interpreting the third dot point:
“Protective actions may need to be considered with regard to external exposure, intake of radioactive material, and radon or thoron inhalation. Radon and thoron exposures should be managed as recommended in Publication 126.”
This point clearly highlights the two tier system alluded to: radon in an underground uranium mine will provide less dose to workers than that received by many office workers who are not currently regulated. By delineating NORM as an existing exposure situation (except for uranium mining and milling) it drives regulators towards having a two tiered system that might not be possible to defend.
Interpreting the fourth dot point:
“NORM presents no real prospect of a radiological emergency leading to tissue reactions or immediate danger to life, but may pose an issue of environmental contamination.”
The “issue of environmental contamination” in a strictly environmental sense is highly unlikely to fail current ICRP guidance on protection of the environment. ICRP are flagging NORM as a potential political issue.
Interpreting the fifth dot point:
“An integrated and graded approach to protection is recommended, starting with strategies already implemented to manage other workplace hazards.”
ICRP seem to be advising that in many cases standard OH&S procedures will suffice for many forms of NORM protection. For example, respiratory protection for silicosis prevention will easily deal with known NORM concentrations in air. However, the graded approach is promoted again with no real advice as to how it is to be applied.
Page 8, Para 13: - Advises that mining of uranium and thorium for their radioactive properties are planned practices. So we have Australian uranium mines that will be controlled as planned practices; current Australian mineral sand mines that will be existing exposure situations. Where does that leave a prospective monazite extraction plant? Such plants are not built to deliberately extract thorium (rather they are after the rare earths), but is such to be treated as an existing or planned exposure situation? If such mineral sand mining moves to an existing exposure framework within Victoria, how will the application of the “nuclear trigger” under the EPBC Act of the Commonwealth be implemented differently if at all?
Page 8, Para 14: Advises that “Thus, radon and thoron exposures in industries involving NORM should be managed in accordance with the approach of Publication 126 and will not be considered explicitly in this publication.” Such is fine if and only if radon and thoron are the only dose pathways. In an environment where there are other considerations, such as solid particulate emissions, it is entirely possible that there might be a combination of existing and planned exposure situations. Such would not be a useful outcome.
Page 8, Para 16: Advises that this publication will specifically address protection of the environment from NORM. Environmental assessments are becoming an integral part of large scale projects with potential for offsite radionuclide transfer and consideration of post-rehabilitation remediation with environmental restoration. To get an existing exposure situation with little human health impact to perform a radiation environment assessment will require new forms of controls that are not currently in legislation.
Page 14, Para 27: Advises that NORM impact to the environment should be assessed, yet proposes an effective relaxation of limits for NORM industries. If human health requirements are being relaxed, then why would there be concern regarding protection of the environment? Does this document provide any advice as to the graded approach for determining acceptability for environmental exposure in a framework where dose limits for people have been seemingly abandoned?
Page 15, Para 33: Advises that “The Commission considers human and environmental exposures resulting from industries involving NORM as existing exposure situations. The source is not deliberately introduced in the industrial process for its radioactive properties; it already exists in material used in the process or industry, and any protection decisions to control the exposure are made in that context. The process in which NORM in raw materials is concentrated, with changes of chemical-physical form resulting in production of radioactive release, residue and waste, is not for the purpose of introducing a new radioactive source; it is incidental even though it has to be managed. However, the Commission considers that when NORM is processed for its radioactive, fissile or fertile properties, it is a planned exposure situation.”. This implies that irrespective of the activity concentration of the radionuclides that comprise NORM that (fissile caveat excepted) such are existing exposures. It appears to indicate that the ICRP are ignoring the traditional definition of a radioactive substance in favour of preferential treatment in the application of activity concentration limits to some circumstances where clearly controlled amounts of radionuclides will certainly exist. Why then is such different treatment required?
Page 15, para 34: Advises that “In existing exposure situations, because the source already exists when decisions on control are taken, the principle of application of dose limits is, a priori, not relevant.” Agreed. However, in the case of many of these practices that are yet to commence, the source does not already exist as the material has not been extracted and/or concentrated via technically enhanced means. Unmodified NORM is clearly exempt; modified NORM that triggers the application of controls seems to be proposed to be either planned exposure or existing exposure depending upon whether government commenced controls at the commencement of the practice or when the practice was well underway. If such is the outcome of the adoption of this document, I cannot imagine why any government regulatory agency would support it. To do so would imply that the regulatory agency can choose to ignore or regulate as they see fit. Such would not be envisaged to be a consistent outcome from the ICRP perspective.
Page 16, Para 35: Advises that “A graded approach, commensurate to the level of the risk as well as other considerations such as economic and societal, is appropriate and particularly relevant for industries involving NORM due to economic importance of industries, large volumes of residues and wastes and limited options for management, moderate level of doses, and potentially high cost of regulation in relation to reduction in exposure.”. This sentence from the ICRP suggests it is far more about the economics than radiation protection. Yes, such risks may be small. However, to merely just move to a higher risk limit by virtue of higher dose/reference levels means that the true risk is never established. Such a move by the ICRP appears to be more related to the application of principles for political and economic ends potentially at the expense of transparent radiation protection. It is considered such advice might be outside the scope of the ICRP to provide.
Page 16, Para 39: Advises that exposure at work, if NORM, is not occupational as the material is natural. The communication of this concept to impacted stakeholders would be difficult. To date, the ICRP has limited the definition of “occupational exposure” to radiation exposures incurred at work as a result of situations that can reasonably be regarded as being the responsibility of the operating management. There was the special case of radon in the workplace. The ICRP have traditionally treated those regarded as not occupationally exposed as members of the public for radiation protection purposes. The ICRP now want to say that NORM exposure at work is non-occupational, but that the operating management needs to consider the exposure of workers who are not occupationally exposed. It is considered that this is confusing in the extreme as it will mean that this group of workers who are non-occupationally exposed will be afforded not the protection equivalent to a member of the public but rather some reference dose level greater than 1 mSv per annum. It is felt that regulatory bodies will be struggling to communicate this to the wider public, let alone within the confines of government agencies.
Page 17, Para 41: Advises that “In rare cases, the level of dose or the application of special working procedures is needed for radiological protection purposes., In these cases, the measures recommended for occupationally exposed workers would apply (ICRP, 1997).” Decisions concerning rarity are seemingly left to the discretion of the regulatory authority. They then say “The Commission’s recommendations should not be interpreted as requiring all elements of a protection program irrespective of the circumstances. The approach should be graded, based on the hazards present.” The ICRP are not being very clear in this regard, retreating to the graded approach (fine) but without clear guidance as to a dose or reference level beyond which the application of controls would be expected.
Page 17, Para 43: Advises that “environmental exposure is dealt with on the basis of common environmental standards, starting with an environmental impact assessment (EIA) considering the presence of NORM.” Such an EIA/EES would inevitably also focus upon human health risk. But again the question remains, is this document effectively recommending flexible adoption of health risk standards based upon NORM-ness while not seeking the same flexibility for non-human biota based upon NORM-ness? It doesn’t feel quite altogether at this point.
Page 17, Para 46: Advises that “As such, justification decisions (regarding radiation protection strategies(my insert)) could benefit from a stakeholder involvement process.” In a practical sense for large scale projects such is done via the EES process. However, this process is for known NORM industries prior to the commencement of the practice. To require stakeholder consultation to effectively review justification of an existing unknown NORM practice (i.e. where NORMS are discovered subsequent to the commencement of the practice) seems unnecessarily complicated. Under such circumstances it usually remains to government to investigate such NORM sources and then decide whether anything needs to be done if such NORM sources are present in controllable amounts. It may be that government decides that no formal regulation is required as the amounts involved are below regulatory concern (i.e. below prescribed levels and therefor outside the scope of control of radiation protection legislation). All stakeholder consultation has done at that point is make radiation an issue where it need not have been, to the advantage of nobody.
Page 17, Para 47: Advises that “Since many industries involving NORM already exist, the Commission recommends the establishment at national level of a list of industries involving NORM for which a radiological risk assessment should be undertaken in order to determine if a protection strategy is justified.” The RHC tried this and the momentum was lost when the subject of coal came up, leading to the cessation of the provision of broad national advice in this sector. The sector certainly needs to be assessed.
Page 18, Para 50: Advises of the ethical value of justice, referring to ICRP Publication 138 “Ethical Foundations of the System of Radiation Protection”. If the concept of “environmental justice” creeps into radiation protection, it will make it very difficult to continue with some practices where the benefits far outweigh the risks, but the distribution of doses is very inequitable. Traditionally, radiation protection has been a utilitarian framework with respect to its application of ethics in that health protection framework. To seemingly start moving towards what appears to be a disguised egalitarian framework implies that equitable protection of all individuals may be required at some point; something it is not possible to achieve easily and potentially threatens some radiation practices. Sound ethical decisions such should rest with those competent to make them. Increasingly it appears that social justice advocates do not accept decisions by regulatory authorities; the science itself is becoming irrelevant, with decisions made on feelings and other non-health protection principles.
Page 19, Para 54: Advises on the use of reference levels as dose criteria. The terminology is interesting, insofar as it effectively reduces to one of a design constraint for the purposes of optimisation, with added emphasis on reducing dose distribution inequities. It is considered that dose distribution inequities can never be zero (i.e. someone has to actually perform the practice from which all benefit) so the environmental justice concept can never fully work in the radiation protection framework.
Page 19, Para 55: Advises “For existing exposure situations, the Commission recommends setting reference levels typically within the 1 to 20 mSv per year band as presented in Table 5 of Publication 103 (ICRP, 2007a), and with the possibility that the reference level could be lower than 1 mSv per year.” So, for NORM practices there is the suggestion of reference levels (dose constraints) below 1 mSv per year? How does this mesh with the ICRP thinking in this document of permitting the selection of reference levels well above the dose limit for members of the public? The document appears to be postulating a framework within which all is possible. The flexibility attributed to NORM practices is to be denied non-NORM practices. At the end of the day, if any material is controllable, why wouldn’t any regulator apply the common platform of legislative controls? Why does the ICRP appear to want what can be argued as either tighter controls or lesser controls for NORM practices?
Page 19, Para 58: Advises that “The Commission recognises that some authorities have already specified the application of dose limits for some industries involving NORM. Such use is understandable, as a limit is frequently used as one regulatory mechanism to judge the acceptability of a radiation control program.” For controlled radioactive substances, irrespective of NORM-ness, demonstration of compliance with the dose limits is most certainly used as a regulatory mechanism, if not the prime one.
ICRP go on to say in Para 58 that such is OK. “Such a use is not unacceptable in circumstances when the source is well characterised, and the control programs have been established. However, specifying a limit for regulatory purposes is not meant to imply that the situation has been, or needs to be, transformed into a planned exposure situation.” To date, treating the use of controllable concentrations of radionuclides as planned practices after allowing for unmodified raw materials to be totally exempt from controls has not presented the alleged over-regulation perceived by the ICRP, at least here in Australia.
Further in Para 58: “In the vast majority of industries involving NORM, the application of “limits” expressed in terms of dose provides no real additional protection for workers, and may entail administrative burdens that are not in keeping with efficient and effective use of resources.” The ICRP is making a rather large value judgement here; such is a judgement best left to regulatory bodies with all the drivers visible to the regulatory bodies that are invisible to the ICRP. Companies conducting radiation practices, whether NORM or not, discuss the degree of effort required to be put into radiation control programs operationally via the Radiation Management Plan that regulators require
for large scale practices. It is also considered that despite the ICRP claiming that “limits” don’t provide additional protection for workers, the ICRP is now wanting a requirement for the specification of reference levels (dose criteria read dose constraint) for NORM practices. How can a reference level be expressed other than a dose criteria/dose constraint in millisievert per year?
Page 20, Para 59: Cites “societal” rather than “social” factors as the caveat on optimisation. What does the change of wording imply? Also, whys does the ICRP recommend such a protracted and iterative regulatory process merged with stakeholders at every step of the way if indeed, as it postulates, the bulk of NORM practices effectively deliver miniscule doses?
Page 20, para 60: Advises that “In this iterative process, the Commission considers that the search for equity in the distribution of individual exposures is an important aspect (ICRP, 2006). It should be noted that, in industries involving NORM, the distribution of individual doses for both workers and members of the public may be very large. The protection efforts should focus individuals on the higher dose tail of the distributions, i.e. on the most exposed individuals, so as to determine if efforts are reasonable to reduce their exposures, while simultaneously trying to reasonably reduce the exposure of the whole exposed population.” If the exposure to workers is such, irrespective of the controllability of the radioactive material involved, that the practice requires the application of regulatory controls purely for occupational radiation protection reasons, then such would be applied. In cases where the estimated or known doses to the population are a mere fraction of the public dose limit, why would any effort need to be expended to reduce it further?
Page 20, Para 61: Advises as to the ICRP’s desire for uber-transparency. This point contrasts sharply with the ICRP’s statements earlier that public doses are effectively near zero from the majority of NORM practices and that occupational doses are also quite low. There is an inconsistency here.
Page 22, Para 70: Advises that “Protection of workers in industries involving NORM should be based on a graded approach to control radiation exposures, according to the annual effective dose (due to the activities involving NORM) that is likely to be received and the scope for dose reduction that may be necessary.” Yes, but how does applying a reference level (dose criteria aka dose constraint) differ from applying standard regulation to the practice (assuming it has controlled radioactive materials) with optimisation?
Page 22, Para 71: Advises that “In practice, a graded approach can be realised through the selection of suitable dose reference levels ..”. The benefits in treating NORM practices differently has not been established.
Page 22 Para 72: Advises that “The practical implementation of this approach will also help to determine whether or not the workers should be considered as occupationally exposed to radiation.” It appears to be inferring that if your protection measures are adequate your workers are not occupationally exposed (and vice versa). If occupationally exposed, do the traditional occupational dose limits apply? For planned practices, occupational dose limits would apply. However, it appears that the ICRP wants to permit a framework in which people who are exposed to radiation at work are classified as non-occupationally exposed and/or occupationally exposed where traditional dose limits would not apply as they are in an existing exposure situation. If it is confusing for regulators, then what will the public and companies think of it?
Page 22, Para 73: Advises that “Since the industries involving NORM are so diverse, there is no unique numerical value which is appropriate as a reference level for all of them. According to the characteristics of the exposure situation, notably the actual and potential exposure pathways, the individual doses distribution and the prospect for optimisation, the appropriate reference level can be selected”. This point appears to be equating the reference level with a dose constraint based upon traditional optimisation considerations. Dose constraints have to date been determined by those conducting the practice; it now appears that for NORM practices the ICRP wants governments to decide what the dose constraints for respective industry sectors might be.
Page 22, Para 74 cites that “the selection of a reference level above 10 mSv per year would not be necessary in terms of radiological protection”. Where does this leave any offence provision? i.e. is it an offence to exceed a government determined reference level in a non-regulated sector that may have controllable amounts of radioactivity?
Page 22, Para 75: Advises that “these doses (reference levels) exclude exposures from radon and thoron.” What does this mean for the ICRP’s additivity principle? Does it now only apply to planned practices? And how does such a partitioning for NORM and non-NORM benefit anyone? For non-NORM practices, radon is an integral component of the additive dose for regulatory compliance considerations. For some NORM practices, the ICRP seems to be indicating that it either is or it isn’t dependent upon whether the NORM practice is a planned practice. For example, uranium mining it would be; mineral sand mining it would not be. Is this a correct interpretation?
Page 22, Para 76: Advises that “In most situations, the residual doses are not expected to exceed the reference level, particularly after the effective implementation of protective measures. The reference level remains useful to allow judgement on the appropriate functioning of the program, and to indicate if modifications of the program are needed.” The reference level is a form of government mandated dose constraint. It is foreseeable that nine different reference levels for identical NORM practices will be established around Australia.
Pages 23-26, Paras 79 to 99: All straightforward and common sense, save for a few aspects. How do regulators get NORM industries to do this if the regulators are not applying planned exposure controls as they do for all other non-NORM practices? Current regulatory tools do not readily exist for existing exposure situations. It seems the ICRP want to treat people at work in NORM practices identical to those in non-NORM sectors, but with differing dose limits/constraints/reference levels. “Why” is the real question here.
Page 26, Paras 100: Advises that “The general approach to the protection of the public should also start with a characterisation of the exposure situation (who is exposed, when, where and how), including analysis of exposure pathways and dose assessments. This characterisation forms the basis for the justification of a protection strategy.” The “justification of a protection strategy”? Considering that the ICRP is insisting upon such practices being treated as existing exposure situations, they wish to see applied quite similar controls as for regulated practices (irrespective of the regulatory controllable nature of the radioactive materials involved) and with flexible dose limits (aka reference levels).
Page 26, Para 100: Continues - Then the optimisation process should be implemented, including the selection of a reference level, the selection and the implementation of the protective actions, the involvement of stakeholders in the decision-making process and the provision of a long-term monitoring of the situation if necessary.” The ICRP seemingly want regulatory bodies to involve the public when selecting the reference level associated with a NORM practice that the ICRP does not want subjected to the usual suite of formal regulatory controls. It is considered that such an approach will inevitably result in the selection of differing optimisation end-points by way of government decided reference levels (aka dose constraints that will appear to the public to be limits) for identical practices in different jurisdictions. It is apparent that the loudest public outcry will produce the lowest reference levels. If this outcome is what the ICRP is referring to by way of “societal factors” using its new terminology for the ALARA caveat, then it is considered that the concept of justice applied in the form of “environmental justice” is more important than effectively optimised regulatory controls for health. The public will likely always want lower reference levels than the regulatory body. At some point, a public will place so much political pressure on a government that the only option for government is to insist on a cessation of the practice despite its many benefits to the community and society as a whole. Outcomes such as this are to be avoided. It is considered that treating above exemption level NORM practices as planned exposure situations permits appropriate rights of appeal as well as offering government a preferred regulatory framework with which to deal with NORM practices.
Page 26, Para 102: Advises that “The reference level for the protection of the public should be selected below a few mSv per year. In some cases of public exposure for industries involving NORM, a reference level less than 1 mSv per year may, in fact, be the most appropriate taking into account the distribution of doses that exists. The protection of the public should be addressed as a whole, i.e. taking into account the different pathways. In a given situation, the pathways need to be considered with respect to NORM discharge, waste, residue and possible legacy sites. In practice, the most exposed individuals to each pathway belong to different groups so that the reference level can generally be applied to any given pathway.” The choice of a reference level is quite flexible, but again the question arises: why would any government wish to treat levels of controllable radioactivity differently from planned practices? Governments will be placed in the position of saying that it is
acceptable for members of the public to receive (say) 4 mSv per annum from a mineral sand mine in an environment where such have been to date treated as planned practices, with cumulative radiation doses from all pathways (including radon) mandatorily confined to less than 1 mSv per annum. If our understanding of the ICRP’s direction to treat mineral sand mining as an existing exposure situation is correct, then (if/when this current document is published and adopted within Australia) companies currently conducting mineral sand mining and related operations will be able to effectively stop their current monitoring effort as the optimisation point for them of not doing anything regarding public dose reduction would be quite hard to argue against, given a few mSv per annum to the public offsite. This situation would create an tension for the government that would be exceedingly difficult to resolve without treating such practices as planned exposure situations.
Page 26, Para 103: Cites effluents from NORM practices should be accounted for. Specifically mentions oil and gas extraction, phosphate processing and coal combustion.
Page 26, Para 104: Clearly identifies that the radiological characteristics of the discharge must be established, along with potential exposure pathways and radionuclide mobility. Similarly done as for planned practices.
Page 26, Para 105: Again requires stakeholder consultation in the selection of the reference level. It is difficult to imagine how this would lead to better outcomes for any regulatory authority or government than treating such practices as planned exposures.
Page 26, Para 109: Advises that “All waste should be characterised in order to determine the proper methods for disposal. Waste treatment should be considered and performed as relevant in the optimisation process, although concentration of wastes to high levels can pose challenges. The issue of waste should be considered from its generation to final disposal when starting or designing a new project (‘from cradle to grave’).” This conflicts with the notion of treating NORM practices as existing exposure situations, where there is no cradle.
Page 26, Para 110: Advises that “The disposal of waste with higher concentrations of radionuclides should be consistent with the management of radioactive waste.” The ICRP appear to want this waste (presumably now controllable material) treated as if it is part of a planned practice. One might ask if the respective reference level for such disposal should be different to that for planned exposures, particularly given the ICRP’s move towards greater transparency through stakeholder participation in the setting of such reference levels. Would a few mSv per year be acceptable? In the context of this document, it would appear so.
Page 28, Para 114: Advises that “Occupational exposures in the manufacture and handling of building materials are usually low but they should be managed in a graded approach as in any other industry involving NORM.” This requirement would require identification and quantification of NORM in building products to permit the application of such a graded approach. There has been some historical work done within Australia to inform this matter. However, such work might require refreshing. Consulting with affected stakeholders on this subject would be challenging.
Page 28, Para 115: Advises that “The reference level for building materials should be of the order of 1 mSv y-1, or less, expressed as effective dose caused by external gamma radiation to members of the public. A reference level of this order should also ensure that any radon exhalation from 226Ra in building materials is unlikely to be the cause for the reference levels set for indoor radon concentration to be exceeded.” It is felt that the ICRP is splitting hairs here; it wants reference levels for NORM practices set at a few mSv per annum for members of the public but seeks to limit exposure resulting from NORM in building products to 1 mSv or less. It is as if the default position has already been decided that persons who work with building materials are non-occupationally exposed.
Page 28, Para 117: Advises that “A protection strategy should be established with the aim to promote building materials that do not exceed the reference level. The strategy may encompass measures such as providing information on the levels of exposure caused by different building materials, labelling of materials, suggesting the use of materials with low radioactive concentration or limiting the use of certain materials causing significant exposures. “ Such would require the use of a derived quantity such as an activity concentration index (mentioned in Para 116). Given that the reference level is equivalent to a dose constraint, it is the sum total of the building materials that are required to
be considered with respect to seeking to keep below the reference level. Given such doses are low, it seems a lot of additional unnecessary stress to pursue this issue. However, it is noted that some countries do indeed have difficulties in this area. In order to know that there is no difficulty, it may be required that representative samples of all commercial building products undergo assessment. Such might be best written into the Australian Standards for building products.
Page 29, Para 119: Advises that “There may be a need to apply a similar approach for other construction materials such as those used for foundations of houses, surfaces of yards, playgrounds, streets and roads, as well as, bridges and other similar structures. Dose assessments and separate derived activity concentration indexes may need to be considered.” Playgrounds would be particularly challenging, given the recommended increased requirement for stakeholder consultation.
Page 29, Para 121: Advises that “The issue of legacy sites is in the scope of a future ICRP Publication in preparation, therefore the present publication provides only a few general considerations.” Legacy sites really are an existing exposure situation. The general advice provided in
Paras 120 to 125 makes broad sense, save for the statement in Para 124 mandating that any workers cleaning up such a site are occupationally exposed. The earlier ICRP advice in this draft was that occupational worker status was dependent upon the success of the optimisation measures chosen (my paraphrasing, see Page 22 Para 72 comments above). Again, some confusion is inevitable given all of the permutations and combinations of circumstances that are possible.
Pages 30 and 31, Paras 126 to 133: Cites general advice regarding protection of the environment and is consistent with that being implemented for planned practices, with the exception of the selection of environmental reference levels via stakeholder consultation. There is the obvious problem of such environmental reference levels being different from the current ICRP guidance values for protection of the environment. Note that estimation of environmental risk would still require considerable work regarding characterisation of the source terms and pathways.