DNA 1240H-2 The dose rate at 3 ft above the sinb over the exposure point may be expressed by: nRBe- (ux)! dap = dA We (r/nr) (17-34) h= -3 From inspection of Fqs.17-32,17-33,and 17-34 it is apparent that dose rate ratios required in Fq.l’-3 to evaluate the shielding factor have the following equivalences: per lin)! (an) as RP n(x)’ aa unxe fo, ze tux) 7 ? (17-35) pte aa J), a3n a «Re Be” (ux)" aa sae h= -3) The evaluation of the integrals of Eq. 17-35 for all the energies in the source spectra would be an extremely lengthy task, even when machinecommited. Therefore, the actual spectra have been replaced with pseudospectra, as described in 17.55. f&valuation of the ratios cf Eq. 17-% has been carried out for the five gamma-ray energies of the pseudospectra, for various distances below the slab, and for slab thicknesses of 0 to 10 inches. Results are presented graphically in Ref. 71. Note that Ref.71 uses the following symbols: I, instead of a) 55 Igo instead of d, I instead of dpr cOPY E L B A L I A V A BEST 17-84 Sn ee ey cette teen ameaa ee = ee ee we re me re ee re er ee ee ee ee ee