건축자재에 발생되는 라돈/토론 농도측정

Abstract

The annual average dose of radiation exposure to Korean people is 3.6 mSv and 50% of thisamount is known to be by the exposure to radon gas. Such radiation exposure to radon has been knownto be caused by the inflow of radon gas mainly through the cracks in buildings but the recently reportedcause of radiation exposure to radon inside buildings even such as high-rise apartments is the radiationfrom construction materials. In this study, in order to investigate the current situation through measuringthe radon radiation from the construction materials on sale through construction material shops inGwangju Metropolitan, two acrylic boxes in 5T thickness and 216L volume were produced using a movablesuccessive radon monitoring device RTM 1688-2 in silicon surface barrier type which could measure theconcentration of radon and thoron simultaneously. After putting the construction materials bought inconstruction material shops in Gwangju to the boxes and sealing them, radon concentration was measuredand recorded for 10 hours from the 91st hour to the 100th hour from 3.8 days which would be requiredto reach 50% of Rn-222 concentration against Ra-226 concentration. In the radon concentration radiatedfrom the sample materials, plaster-tex (K) showed the highest value of 39.6 Bq/kg and followed byplaster-tex (L) of 23.6 Bq/kg and plaster-tex (B) of 17.4 Bq/kg. The result of the measurement showedthat an effective reduction of radiation had been achieved through the Korean authority's continuousregulation and management on the usage of phospho-gypsum as plaster-tex and the mixture usage offly-ash cement. From this result, the construction materials on sale in Gwangju Metropolitan could bedeemed to be somewhat safe but the radon radiation amount should be traced and observed continuouslybecause there could be different amount of radiation according to the difference of mixture depending onthe manufacturing period of construction materials in the aspect of their characteristic.