Table 4.

Calculated dose reduction factors (DRF) for examined composites

Composite	Additive(s)	d (g/cm2) (1 layer)	DRFa	DRFb	d (g/cm2) (2 layers)	DRFa	DRFb
M1	Bi	0.195	0.79	0.78	0.391	0.61	0.60
M2	Bi + W	0.244	0.72	0.70	0.488	0.50	0.49
M3	Bi + W + Gd	0.230	0.73	0.72	0.460	0.51	0.50
M4	Bi + W + Gd + Sb	0.236	0.73	0.72	0.472	0.52	0.51
G1	Bi	0.134	0.89	0.88	0.267	0.78	0.77
G2	Bi + W	0.178	0.82	0.81	0.355	0.67	0.66
G3	Bi + W + Gd	0.176	0.82	0.81	0.352	0.66	0.65
G4	Bi + W + Gd + Sb	0.174	0.80	0.80	0.349	0.65	0.64
EP	Bi + W + Gd	0.162	0.79	0.78	0.322	0.62	0.61
Z	Bi	0.172	0.78	0.77	0.344	0.61	0.60

^aX-ray fluorescence radiation of Bi, W and Gd involved

^bOnly for 122.1 and 136.5 keV Co⁵⁷ photons