Estimation of possible radiological hazards from natural radioactivity in commercially-utilized ornamental and countertops granite tiles

► The study presents the activity concentrations of radionuclides in granite tile samples. ► The activity concentrations of radionuclides are measured by gamma spectrometer.. ► In this study, possible radiological hazards from usage of these materials are estimated. ► The external exposure index and internal index are calculated. ► The indoor absorbed gamma dose rate and the corresponding annual effective dose are evaluated.