INDOOR RADON CONCENTRATION RELATED TO GEOLOGICAL AREAS AT DIFFERENT WORKPLACES OF ALBANIA

Radon exposure in the workplace is one of the main exposures to the population after that in dwellings. These workplaces are generally at the ground and/or first floor, where radon concentration is generally higher than at upper ones. This study deals with the measurements of indoor radon concentration in several workplaces located in different geological conditions. Measurements of indoor radon concentration have been carried out using passive bare detectors based on CR -39 in 50 workplaces, including one site at the Centre of Applied Nuclear Physics, Tirana. According to the principles of the methodology, the radon passive detectors have been located inside the workplaces for three months exposure, allowing the calculation of average values, which represent much better the true values of the radon concentration inside of a closed environment. The exposure time of detectors was performed during period January–April 2014. According to the assessment made by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), radon in the natural environment constitutes about 50% of the human exposure to natural radiation or 1.2 mSv/year. The measurements were used to calculate the effective dose due to the radon contribution (mSv/y). Based on the results of the measurements, the minimum value of the radon concentration found is 53 Bq/m3 to 400 Bq/m3 in workplaces, while the reference levels are 300 Bq/m3. Around 90% of the radon concentration values are within reference levels. The results of this study represent a variation of radon concentration related to geological composition. More detailed studies are needed in areas with different geology and construction materials for a better spatial distribution of radon concentration, particularly in public places.