Study on measurement and quantitative analysis of Radon-222 emitted from construction materials

The air concentrations of radon and thoron (Rn-220) emitted to the atmosphere from 4 types of construction materials (brick, tile, red clay tile, and gypsum tile) were measured and analyzed using continuous radon monitoring equipment (RTM 1688-2). Of the four samples examined, the cement brick showed the highest levels of radon emission, whereas the red clay tile showed the highest level of thoron emission. Gypsum tile showed the lowest radon and thoron emission. The level of radon emission was estimated based on the materials required for the construction per unit area (3.3 m2) in an actual construction. The values for cement brick were highest at 10,875.0 Bq/m3 for radon and 1,508.3 Bq/m3 for thoron. The value for gypsum tile was lowest for radon (24.6 Bq/m3), whereas the value for tile was lowest for thoron (21.0 Bq/m3). This study suggests methods to examine the effects of radon and reduce the personal radiation exposure dose. Government should be active in publicizing and encouraging the use of construction materials with lower levels of radon emission.

► The concentrations of radon and thoron emitted from brick, tile, red clay tile, and gypsum tile were measured.
► Cement brick showed the highest levels of radon emission.
► Red clay tile showed the highest levels of thoron emission.