c. ORNL From NUREG/CR - 0150 Vol. 2, 1979 Estimates of Internal Dose Equivalent to 22 Target Organs for Radionuclides Fuel-Cycle Occurring in Routine Releases from Nuclear Facilities, Vol.ll; D.E. Dunning, Jr., S.R. Bernard, P.J. Walsh, G.G Killough, and J.C. Pleasant. This analysis is essentially that of ICRP. from Marshall, Thorne, ICRP etc. It is based on the same data In this report they 9ive “S-Factors” for various target organs in rem/pCi-d. For a Quality factor of 20 the “S Factor” for red marrow is 0.90 rem/pCi-d and for endosteal cells in 12.58 rem/UCi-d. 12.58 = ,40 m D. The ratio of endosteal cells to red marrow is, therefore, UNSCEAR In the 1982 UNSCEAR report the committed dose per unit intake of Pu is listed as 0.008 pGy/Ba for red marrow and 0.1 pGy/Bq for bone livin9 cells. Thus the ratio of endosteal cells to red marrow is = 12.5 +-& E. Comparison of the endosteal cell to red marrow dose ratio for the various methods. The ratio of bone surface to bone marrow dose from Spiers is 12, from ICRP 13, from ORNL 14 and from UNCSEAR 12.5. Thus, from these comparisons, there is very little difference in the ratio of endosteal cell to bone marrow dose for the various options one could select for the calculation. 2. Absolute Magnitude of the Bone Marrow Dose Conversion. A. Spiers Spiers lists the dose conversion for bone marrow in reference 1 as 16.9 rad/y-pCi for a lpCi skeletal content (mineralized skeleton 5000g; endosteal surface 16m2). This converts to 338 rem/pCi-y for a QF = 20. 3