Abstract
•Rock sample with the highest % of Fe showed better ability at low gamma energies.•Concrete showed the best shielding properties at the 140 and 364 keV.•Rocks are better used for medical diagnostic radiology structures.•Concrete and brick are better used for diagnostic nuclear medicine structures.•Mountainous rocks could be used as means of protecting the public.
Occupational and public radiation exposure could be minimized with the use of rocks. Rocks are relatively high-density materials, which could be used as a protective shielding barrier at facilities where ionizing radiation is used. These can include medical diagnostic radiology (Dental, Mammography, General and CT) and nuclear medicine (NM) centers. There is need to know potential shielding capabilities of rocks at low gamma and nuclear medicine energies; and compare with brick and concrete. In the present study, mass attenuation coefficients (MACs), effective atomic number (EAN) and effective electron density (EED) of the different rock samples were determined using WinXCom computer program and other relevant equations at 20, 30, 40, 60, 140 (Tc-99 m) and 364 keV (I-131). The results were compared with that of concrete and brick at the energies of interest. The result of this work shows that rocks are better used instead of concrete and brick at 20, 30, 40 and 60 keV. At 140 and 364 keV, all the considered materials performed nearly same which implies all could be used while the optimum considering all other necessary factors should be preferred.