Dosimetric quantities


Draft document: Dosimetric quantities
Submitted by Hosin Choi, Korean Association for Radiation Protection
Commenting on behalf of the organisation

General: Definition of dose quantities for protection On the new name 'radiation weighted dose': It is true that the names dose equivalent and equivalent dose are troublesome. However, is the trouble so severe that we have to change the name after 15 years when we are accustomed to those old names? The new name for equivalent dose, radiation weighted dose, does not seem to be accepted unanimously because the name by itself does not carry the exact physical meaning of the quantity. What we weight is quality or importance of radiation rather than radiation itself. The name not going with the quantity might not be durable. Meanwhile, dose equivalent and equivalent dose are conceptually quite similar. Why should we call them by completely different names? Specific: Page 14. In the equation defining the radiation weighted dose(eqn. 3.4), the weighted absorbed doses are summed over types of radiations. We do not see the reason why they are summed to define radiation weighted dose. The radiation weighted dose may stand alone for every type of radiation. The same problem arises in the definition of effective dose. Page 28. In the middle of the second para. 'ICRP Publication 92(ICRP 2003a)' can be replaced by 'equation (4.1)'. Page 28. The first sentence following eqn.(4.7) (Obviously....complex.) may be struck out. Page 34. The notations used for specific activity(a_s), activity concentration(c_nuclide) and activity per unit area(a_a) are not consistent. We do not think it is appropriate for the Commission to designate the notation for those quantities. We prefer 'surface activity density' to 'activity per unit area'. Page 34. In the definition of committed dose, we prefer 'delivered up to a specified time' to 'delivered within a specified time period'. Page 34. Avoid to use dot operator to mean multiplication in eqn.(5.3). Also in eqn.(5.4) on page 35. Page 35, 1st para. It is not clear what is the meaning of the sentence 'Depending on....external exposure.' Page 35, eqn.(5.4). It is not appropriate to explain that the effective dose can be estimated from operational quantities because intake is not defined as an operational quantity. Page 36. The MIRD type phantom is also regarded as one of the computational phantom. Why should not we use 'voxel phantom'? Page 36. Para. defining ALI. '20mSv(the average annual limit' should read '20mSv(the average share of limit'. We do not see the reason of changing unit of dose(Sv to mSv) in the dose coefficient. Page 37. 1st para. in section 5.3. 'as for operational exposure' should be 'as for occupational exposure'. We prefer 'prediction of the effluent' to 'simulation of the effluent' in the first dot item. Page 43. 2nd para. The Commission take the amount 10 micro-sievert a year as a small fraction of doses from natural sources. Is not this amount too small when the doses from natural sources are in the range of a few mSv?


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