Relating measurements of background radiation to the appropriateness of property units : – A field study in Namibia

Abstract: This thesis is about mapping background radiation in Namibia; specifically in the townships of: Windhoek, Otjiwarongo, Otavi and Tsumeb. No measurements of background radiation in these towns had been carried out before this thesis was done. Even though high levels of background radiation can cause cancer Namibia does not have any laws or recommendations regulating the maximum limits of exposure to background radiation. Our goal was to measure the radiation levels in the four townships mentioned above by using Thermo Luminescent Dosimeters (TLD’s) and carry out instant measurements of background radiation. Then use the results from these measurements to make a map that would be easy for the general public to understand. We have also investigated both the Namibian and the Swedish law to find out if there were any shortcomings in the Namibian law and if it might be possible to use Sweden’s regulations about suitable and appropriate properties in Namibia. The results of the measurements of the background radiation showed that the radiation levels ranged from 0.50 to 2.11 mSv year -1. Compared to the recommended value from the International Conference on Pattern Recognition at 1 mSv year-1the measured values are not exceptionally high. The measurements that were done in this thesis were plotted onto orthophotos of the different townships, thereby creating five maps showing levels of radiation exposure. The levels were colour-coded; green for the lowest, red for highest and yellow and orange for the radiation levels in between. The review of Swedish and Namibian legislation resulted in finding that parts of Sweden’s laws could be applied in Namibia, but some of Namibia’s existing legislation could also be modified to cover radiation exposure. This thesis has concluded that one possible way to mitigate the harmful effects of background radiation and thereby protecting Namibians from acquiring cancer is to expand existing legislation to encompass radiation.