Indoor radon concentrations in residential houses, processing factories, and mines in Neyriz, Iran

Purpose This study aimed to determine radon concentrations in mines, stone processing factories, residential houses, and public areas, as well as calculating its effective dose in Neyriz, Iran. Method A total of 74 alpha Track detectors (CR-39 detector) were installed at the desired locations based on the US-EPA's protocol. After 3 months the detectors were collected and delivered to a Radon Reference Laboratory for analyzing. Results Mean +/- SD, minimum and maximum radon concentrations in the sampling buildings were 29.93 +/- 12.63, 10.33, and 66.76 Bq/m(3), respectively. The effective annual dose was calculated to be 0.75 mSv/year, which was lower than the recommended value. Significant positive correlations were found between radon concentrations and some studied variables including smoking cigarettes, number of cigarettes smoked, duration of smoking, building's age, number of floors, having cracks, use of colors in the building, use of ceramic for flooring, use of stone for flooring, and gas consumption. The number of cigarettes smoked by the residents was the most important predictor of radon concentrations. Radon concentrations were lower than standard values in all sampling locations. Conclusion It is necessary to conduct further studies in the field of regional geology and determine the sources that release radon in these areas to prevent further increases in radon concentration due to the proximity and plurality of mines and factories.