Abstract
Radon-222 is a naturally occurring gas created from the decay of Radium-226. The long-term health risk of breathing radon is lung cancer. One particular place where indoor radon concentrations can exceed national guidelines is in WasteWater Treatment Plants (WWTPs) where treatment processes may contribute to ambient airborne concentrations.
The aim of the paper was to study the radon concentration decrease after the application of corrective measures in a Spanish WWTP. According to first measures, air radon concentration exceeded International Commission Radiologica1 Protection normative ((ICRP) recommends intervention between 400 and 1000 Bq/m3). Therefore, the wastewater treatment plant improved Mechanical forced ventilation to lower occupational exposure. This measure allowed to increase the administrative controls, since the limitation of workers access to the plant changed from 2 h/day (considering a maximum permissible dose of 20 mSv per year averaged over five years) to 7 h/day.
