Abstract

Radon 222 and thoron are of the colorless, odorless and radioactive gases which emissions from the building materials such as black cement and granitic stones. Long term inhalation of Radon increase the risk of lung cancer. In this study, it was tried to compare the effective dose of radon 222 and thoron of indoor air in the black cement warehouses and stone masonry workshops (mainly granite stone) by statistical tests using the results of previous studies. The mean of radon 222 and thoron in the cement storage warehouses were 133.6±33.2 Bq/m3and 21.8±10 Bq/m3and in stone masonry workshops were 134±33 Bq/m3and 47±11.5 Bq/m3, respectively. The effective dose of radon 222 and thoron in black cement warehouses were 1.4±0.3 mSv/y and 0.05±0.02 mSv/y with sum of 1.45±0.32 mSv/y and in stone masonry workshops were 1.41±0.34 mSv/y and 0.11±0.025 mSv/y with sum of 1.52±0.18 mSv/y, respectively. The effective doses of radon 222 black cement warehouses and stone masonry workshops was less than the ICRP standard limits (P<0.001). The effective doses of radon 222 in the black cement warehouses with stone masonry workshops was not different significantly (P value = 0.94), but the effective dose of thoron in stone masonry workshops was higher significantly (P value<0.001). So, measuring and calculating effective dose of thoron indoor air in the stone masonry workshops and storage of decorative stones (mainly granite) are more important. © 2016, International Journal of Pharmacy and Technology. All Rights reserved.