Indoor Radon-222 Concentration Levels Measurements and Exhalation Rates Calculations in Some Offices and Rooms of AAUJ during the Winter and the Spring of 2014

In this study, we report on the radon concentration levels, the radon exhalation rate, and the annual effective dose equivalent in 10 buildings of AAUJ during the winter and the spring of 2014 using the CR-39 track detectors. The inspected facilities include 46 offices, 24 labs, seven storage rooms, nine coffee rooms, a cleaning room, eight bathrooms, four Xeroxing rooms, and three meeting rooms. The indoor radon concentration levels were found to vary from 26 to 258 Bq/m³, with an arithmetic mean and standard deviation of 76.6 and 16.2. In general, the bathrooms and stores were found to have a significant higher radon concentration levels.  The estimated effective dose to the population was found to vary from 0.69 to 2.12 mSv/yr, with a mean of 1.15 mSv/yr. The exhalation rates values were found to vary from 1.92 to 5.20 mBq/m².hr.

The average of the obtained indoor radon concentration was below the indoor radon concentration action level (148 Bq·m^-3) as recommended by Environmental Protection Agency (EPA). Moreover, the effective dose to the population and the exhalation rates, which are 15% and 14% respectively, are higher than the accepted values,  In general, most of the measurements were found to be within the internationally accepted concentration levels of ICRP and hence no remedial action is required.