This study aims to evaluate the effect of particle size on the mass dependent attenuation ability of bulk and nanoparticles PbO. The mass attenuation coefficient. or MAC. of the samples was experimentally calculated using the HPGe detector at various selected energies (between 0. https://safeersappliancers.shop/product-category/bosch-kgn33nl3ag-a-rated-60-40-split-no-frost-fridge-freezer-in-inox-stainless/