|My comment concerns the continuing use of sievert as a common name for the unit of equivalent as well as effective dose, although the possibility of a change was foreseen in the previous draft.
This inevitably leads to mixing of the two concepts with resulting confusion and misunderstanding. The danger of local tissue damage may be overlooked, when a modest effective dose is misinterpreted as a modest local dose. The warning issued in (112) is not a solution to this problem, because “dose” is still the common term in general use, at least by non-professionals. If the Commission does not want to introduce a new name for the unit, the use of equivalent dose should be restricted only to the intermediate step for calculating effective dose. Equivalent dose for description of any local exposure should be discouraged. E.g. in (136), the term should be deleted from the last sentence. Local exposure should always be expressed as absorbed dose in gray, specified by radiation quality if necessary. As such, the equivalent dose does not describe the risk for tissue damage, nor is it a good descriptor of individual cancer risk.
The exposure limits in Table 5 under (241) is an example of an inadequate use of equivalent dose. The dose limits for the lens, skin, hands and feet are dictated solely by the possibility of tissue reactions and should be expressed as absorbed dose in gray. Equivalent dose, on the other hand, is applicable only to stochastic effects and is not correctly used here.