|In our comment to the first draft, The Norwegian Radiation Protection Authority (NRPA) pointed out that the principle of justification is one of the cornerstones in the basic system of radiation protection, and is as such incorporated into the Norwegian radiation protection legislation In the revised draft justification is again highlighted as one of the basic principles of radiation protection, and we feel that the treatment of this topic has improved. However, practical guidance and examples on justification analysis in general is still needed, and particularly in connection with the use of ionising radiation in medico-legal exposures for
security checks, crime investigation, smuggling etc These issues are to-day becoming increasingly important, and should be subjected to a much broader treatment.
In the current draft, the principles of exemption and exclusion are now more clearly defined, and also the concept of clearance is discussed - at least in the corresponding foundation document We are also pleased to note that the justification principle is positively mentioned as a one of the principles governing the process of exemption, together with the "insignificant dose" criteria
The practical application of' dose constraints has now been clarified, and it is underlined that this is a source related concept used for prospective purposes. The distinction between constraints and dose limits is now better explained.. In several paragraphs it is stressed that optimisation shall still be performed below the dose constraint, and thus it is expected that actual doses usually should be lower than the constraint.. It is not quite clear whether this is totally consistent with previous use ofthe term, Le.. as used in ICRP 60.. Here dose constraints were presented as an intergral part of'the optimisation process, i..e,t o some extent the dose constraints represented the optimal level of' dose. If' the meaning and content of'the concept is changed, this should be more clearly explained..
The collective dose concept is now formally defined as a semi-differential or disaggregated quantity, i..e, as collective dose in a given dose interval.. Thus, in principle it will still be possible to use zero as the lower integration limit, even though this is discouraged. We are pleased to note that the statements in the revised text regarding the use of'the collective dose concept is more balanced and less absolute, and we think that the present definition will servve its purpose.
The NRPA welcomes the activities of the ICRP in relation to the development of a system for the protection of the environment from radiation (Chapter 10). Implementation of national (Norwegian) regulations has led to a pressing requirement to introduce viable methods for assessing impacts of radioactive releases on the environment. The plans presented by the Commission with respect to the development of a system based on points of reference primarily through the use of reference animals and plants should facilitate this endeavour substantially. It is also important that this system will harmonize with existing environmental management systems.