Radon exhalation rate from the building materials of Tiruchirappalli district (Tamil Nadu State, India)

Abstract

Tiruchirappalli district has enriched resources of building materials such as stone, granite, sand, brick, cement, etc., which are also supplied to the neighboring districts. Since radon is considered as one of the causative factors for human lung diseases, the measurement of the radon level in these building materials is imperative for the assessment. The samples of building materials were collected from their original sources spread over Tiruchirappalli district. The sealed can technique with solid state nuclear track detector (SSNTD) was employed for the measurement of radon exhalation. The activity concentrations of radon in sedimentary rocks analyzed ranged from 13.2 Bq/m 3 to 218.0 Bq/m 3 with the geometric mean activity of 46.3 Bq/m 3 . However, radon concentrations in igneous rocks are distinctly higher than those of sedimentary rocks and ranged from 95.6 Bq/m 3 to 1140 Bq/m 3 with the geometric mean activity concentration of 392.6 Bq/m 3 . The radon exhalation from sand, brick, and cement were found to be non-uniform (sand: 119.8-656 Bq/m 3 , brick: 31-558 Bq/m 3 , cement: 172-300 Bq/m 3 ). The activity concentration of radon in these building materials follow a descending order: Granite > sand > cement > brick > sand stone. The mass and surface exhalation (E M and E A ) rates also follow the same order. The study concludes that since the radon exhalation from the building materials was less than the International Commission on Radiological Protection limit of 1500 Bq/m 3 , they do not pose any radiological risk.