Comparative Analysis of I-131 Concentration Measurement Methods By Direct and Indirect From The Radioisotopes Production Stack to Outdoor

The Radioisotopes Production Facility at PUSPIPTEK Serpong produces and processes I-131 that can disperse to the settlements (community) and the environment around the Serpong Nuclear Area (SNA). I-131 is produced routinely for medical purposes in hospitals and pharmacies, for both domestic and export. I-131 is a beta and gamma emitting radioactive material and can cause thyroid cancer. The problems are that there are so far no research and in-depth assessment of the air dispersion of a I-131 radioactivity emitted from the radioisotopes production stack to the environment at actual conditions. The research was conducted simultaneously measurement of I-131 radioactivity in the stack of the I-131 radioisotope production facility, Serpong and at houses courtyard (outdoor) of SNA based on the variations of the distance and wind direction in normal condition (no accident). Direct measurement is carried out with a portable in-situ NaI(Tl) detector at outdoor, and with a LaBr3 detector in the stack. Indirect measurement is carried out by using the charcoal filter and vacuum pump in the stack and outdoor. Direct measurement method has many advantages than indirect measurement. Direct measurement method is more accurate, less expensive economically, easier to operate socially, just need an operator on its implementation, portable, and sustainability can be operated continuously. The overall activity concentrations of I-131 on average either by direct or indirect method were still below the standard radioactivity levels of I-131 in the air (530 Bq/m3) based on rule of PERKA BAPETEN No. 7/2013.