Examination of the parameters affecting of 222Rn emanation for some industrial and environmental samples using gamma-spectroscopy

The present work aims to radiologically characterize five samples (monazite, zircon, scale waste originating from petroleum production, black sands and phosphate rocks) from different industrial applications and environments in the Egyptian territory. The first section of the present work discusses the measurement and analysis of 226Ra, 232Th and 40K concentrations. Moreover, the assessment of the hazard indices is given in terms of radium equivalent (Raeq), external hazard index (Hex), internal hazard index (Hin), gamma-activity index (Iγ) and alpha-activity index (Iα). The second section deliberates the 222Rn gas emanated from the samples and studies the physical parameters affecting the emanation process. The results found that the monazite sample has the highest concentration of 226Ra, 232Th and 40K; however, it reached 54435, 442105 and 583 Bq.kg−1, respectively, between the studied samples. Furthermore, black sands and phosphate rock samples exhibit the lowest concentration of 226Ra, 232Th and 40K. Results also show that the radon emanation coefficients decrease while the density of materials increases. [Display omitted] •Measuring the radioactivity concentrations for 226Ra, 232Th and 40K.•Radon activity concentration assessment for natural and industrial samples.•Parameters affecting the radon emanation.•Secular equilibrium in uranium and thorium decay chains.