An-Najah Staff

The indoor radon concentrations in the old city of Nablus have been measured by using Solid State Nuclear Track Detectors (SSNTDs). After ninety days, the (SSNTDs) were collected and etched chemically by (6.25 N) NaOH solution for an hour at a temperature of (98 ± 2) C ° . The number of tracks per unit area in each detector was measured by using an optical microscope with 100 magnification power. lt was found that the radon concentrations vary between (81.31 Bq/m3) to (135.72 Bq! mi ). The values of the average radon concentration inside the kitchens, sleeping and setting rooms are (116.01 Bq m³), (101.78 Bq/ m³), and (79.92 Bq/m³), respectively. The total average radon concentration in homes in the old city of Nablus is found to be equal (98.8 Bq/m³) which corresponds to an average effective dose equivalent of (4.94mSv/y), which is higher than the globally accepted value of (1.3 mSv/y). Poor ventilation is believed to be the main reason for the elevated indoor radon concentrations in the homes of Nablus old city.