The bone-marrow dose-rates to children are calculated ty combining Bennett's model for children with the approach developed by Sriers and used in the UNSCEAR report 22 . . for estimating bone-marrow dcse from the mineral or matrix bone dose. The values used for converting De doses, to bone-marrow and endosteal cell dcses, are 0.314 and 0.434 respectively. Bennett's model also extrapolates to the adult case and ° 0a is combined with the Srtiers approach Tor predicting the bone-marrow doses to adults. The tone mass is assumed to correlate directly with bdocy mass, and : > . : these Gata as a function of age are taxen from Srliers. masses are based upon average data from the U.S. 21 These bedy rorulation and a factor of 0.55 was incorrorated to account for the smaller size of the Enewetekese. . The calcium concentration in bone (sCa/g bone) as a _ function of age is taken from Bennett. 16 In calculating the mineral bone dose (D, dose) in NVO-15C, the was followed, using - z > 18 so approach of ICHP calculated from this mcdel are compared to the 3-rern,yr suide (ICHE for bone for general cublic. However, S) in assessing the annual dose both children and aduits, the bone marrow is taken as the critical organ, . . ~ and the recormendations in ICRP 11 24 . are used. In this model the quality factor is still one (4F = 1), and the “n” factor is no longer epplicable. The bone marrow is considered in the category of sensitive blocd-forming organs, and the corresponding dese guide for such organs is 0.5 rem/yr rather than the 3 rem/yr for mineral bone.