|The draft recommendations make it clear that the Commission regards its recommendations as Decision Aiding and that the final Decision Making process may include other societal concerns and considerations. However it would be beneficial if the commission were to provide more explicit statements on the Scientific basis for many of its recommendations e.g. Activities that are not amenable to control or individual risks attributable to radiation that may be considered insignificant. This would strengthen its declared aim of increasing the transparency and understanding of how decisions have been reached.
While the Commission is to be commended for attempting to simply some of the terminology used in it’s recommendations. In particular there appeared to be little consistency in its use of the new term tissue reactions and the existing term deterministic effects. If these terms are synonymous and the new term is designed to aid understanding then perhaps it should have been used exclusively.
Para (37) The last sentence states ‘…for all these situations to which its recommendations apply (See section 5.4) Should this be section 5.2?
In Para (137) The Commission states that ‘Public exposure includes the fetus of a pregnant radiation worker or of a pregnant patient undergoing a radiological procedure.’ To aid clarity the Commission should consider the addition of a specific dose limit for the fetus in Table 5. In addition it might be useful to repeat this statement in Section 6.3.
In Para (171) the Commission states that ‘Other workers, such as administrative and support staff, are more similar to the general public and are treated as such.’ The consequence of this is that workers who might exceed the dose limit for a member of the public should now be monitored for radiation exposure incurred in the workplace. If this is the Commissions intention, then they should clearly state that workers who may exceed 1mSv per annum should be subject to monitoring of their dose. If this was not the intention of the Commission they should review the statement to ensure that it is not interpreted in this fashion.
Section 5.8.4 Dose constraints for occupational exposure. The adoption of dose constraints for a particular occupation e.g. workers in Nuclear Power Plants will simply result in the dose constraint value becoming the de facto dose limit. Especially given that unplanned (emergency exposures) are subject to a separate dose constraint that may in certain circumstances exceed the Dose Limits recommended by the commission. As a result the Commission should review the continuing need for Dose limits for occupationally exposed persons.
Dose constraints. Proposed revisions to Intervention levels and constraints in these recommendations are confusing. The draft recommendations now use the term constraint for planned exposures where the value from a single source might be limited to <0.3mSv in a year for a member of the public. Yet for emergency situations where intervention with protective actions would be warranted a doses could be 20mSv in a year. In addition for planned exposures the constraint is intended to be an upper bound and that optimisation of the doses should always result in doses below the constraint. Whereas for emergency situations constraints should be viewed a level of ambition and not as a mandatory level which must be achieved. The Commission should consider adopting a different term for the upper bound to demonstrate that optimisation has been achieved in occupational exposures. With another term used for aspirational targets used for emergency situations where doses above the value mean that intervention is always justified but that the optimum intervention may not reduce individual doses to level below the target.
The Commissions statement in para (291) that The distinction between ‘natural’ and ‘man-made’ or ‘artificial’ radiation exposure has proved to be peculiar and unconstructive’ is welcomed. However it is somewhat undermined by the statement in para (342) that societal and political attributes, generally unrelated to radiological protection, usually influences the final decision [on the treatment of natural vs man-made exposures]. It is further undermined by the statement in para (341) that ‘The claim for protection is generally stronger when the source of exposure is a technological by-product rather than when it is considered to be of natural origin.’ While National Governments will take into account societal concerns the Commission should clearly state the scientific basis of its recommendations without adding qualifying statements. This will aid in establishing the transparency and understanding of the basis for the regulations produced nationally particularly where these may deviate from the recommendations of the Commission.
The statement in Para (223) ‘in emergency and existing exposure situations, where exposures are not planned, constraints should be viewed as a level of ambition and not as a mandatory level that must be achieved’ appears inconsistent with the statement in Para (338). This states that ‘In emergency situations, the same approach of optimisation below a dose constraint should be applied. The dose constraint represents the level of dose where action is almost always warranted. Compliance with the constraint is not in itself considered sufficient, optimisation of protection is also required.’ It would be helpful if the Commission were to clarify this issue.
It would be helpful if the statement in Para (338) on interventions – ‘Nevertheless, at some level of dose, approaching that which would cause tissue reactions, some kind of intervention will become almost mandatory. The Commission now considers this level to be 100 mSv either acute or in a year’ was more consistent with the following statement in para (347) ‘For emergency situations where the projected dose from a specific pathway or combination of pathways may approach thresholds for serious deterministic health effects, protective actions are almost always justified a priori’.