ABSTRACT
Radon [[222]Rn] Measurement in the residential environments is very important because of its effecting on human health and causing cancer in the respiratory system. [222]Rn is individually responsible for half of the natural radiation received in humans and influences on human by breathing. Hence, this study was undertaken to access the [222]Rn level in the dormitories of Kerman university of medical science [southeast of Iran] to ensure its safety level. In this study, for measuring [222]Rn level in seven dormitories of the Kerman University of Medical Sciences, the Lucas cell technique was used. This study was undertaken during the winter because of the high concentration of radon in this season due to closed building ambience. In this study, the highest measured radon gas rate was 24.5 Bq/m[3] in Boustan [1]. Average concentrations of the radon gas in all dormitories were 4.7 Bq/m[3], which is lower than the standard level. The results of this study showed that the [222]Rn level in all dormitories was lower than the normal amount [48 Bq/m3] as well as the standard level
ABSTRACT
[131] radionuclide has been widely used for treatment of thyroid cancer and hyperactivity. In this regard the accurate calculation of absorbed dose in thyroid gland and other organs is important. In this study, according to MIRD method, MCNP code was used for calculation of absorbed dose of [131] radioactive sources in any thyroid with specific mass and size. The results of two different geometries spherical and cylindrical shapes for each lobe of thyroid were compared. The results show when the thyroid mass increase from 20gr to 70gr, the absorbed dose per one disintegration increases 4.2%. These results firstly indicate that instead of using the total mass of thyroid in iodine therapy, it would be better to use the calculated active mass of thyroid. Secondly, the variation of absorbed dose per disintegration of [131] should be considered for the measurement of source activity in treatment of thyroid hyperactivity or cancer