The shielding ability of the lead standard and the newly manufactured shielding sheets were compared by measuring the shielding ability of the lead standard using the same method mentioned above. Transmission doses of standard lead are presented in Table 4. It is related with the thickness, and thicker lead or more lead showed better shielding ability. As a result, the average transmission doses and the lead equivalent of the manufactured shielding sheets are presented to explain their shielding ability with the standard lead.