EVALUATION OF DOSE IN SLEEP BY MATTRESS CONTAINING MONAZITE.

Some companies in Korea have sold beds which contain a processed product containing monazite powder. Consumers may receive external exposure by radiation emitted by progeny radionuclides in uranium and thorium, and internal exposure through the breathing of radon progeny radionuclides produced in the decay chain. Thus, in this study, age specific dose conversion factors (mSv y-1 Bq-1) by external exposure and dose conversion factors by internal exposure (mSv y-1 per Bq m-3) were derived. Besides, a dose assessment program were developed to calculate dose by taking into account real conditions. And the age specific dose was evaluated using the radioactive concentration measured by the NSSC. As a results, external exposure was assessed to get effective doses in the range of 0.00086 to 0.0015 mSv y-1 by external exposure and a committed effective doses in the range of 1.3 to 12.26 mSv y-1 by internal exposure for all age groups.