Determination of radon concentration and annual effective dose rate at spas in central afyonkarahisar

The colorless, tasteless, odorless and heaviest inert gas of radon originates from the alpha decay of radium which is the member of Uranium natural radioactive series. Radon is released into the atmosphere trough earth's crust cracks and transporting by ground water. World average of radon contribution to the natural radioactivity is known as about 50% and it is the second factor causing lung cancer after smoking according to World Health Organization report. Therefore, it is necessary to determine the radon activity concentration in dwellings and the annual average effective dose equivalent arising from radon exposure. In this study, radon activity concentration measurements were done at 10 different thermal facilities in Afyonkarahisar using CR-39 nuclear track detectors for one year with three month period. As a result, the radon activity concentrations are 63.88±5.13 Bq/m3 in thermal places, 77,21±8,86 Bq/m3 in offices and annual average effective dose equivalents are 0,403±0,050 mSv in spas, 1,023±0.195 mSv in offices. Obtained results were both compared with known values defined by national and international organizations, and the anomalies in radon activity concentrations in this period were discussed on the dependence of meteorological data. 2014, xi+68 Key words: Radon concentration in dwellings, Spa, CR-39 nuclear track detector, Annual average effective dose equivalent, Meteorological parameters.