Radon levels inside residences in Swaziland

Time-integrated measurements of environmental radiation levels are commonly carried out using solid state nuclear track detectors (SSNTDs). These detectors are particularly suitable for monitoring indoor radiation. Levels of radon were measured, during winter and summer seasons, inside 130 traditional and modern houses and multi-family apartment buildings. The traditional houses, modern houses and apartment buildings had average radon levels of 62 Bq.m-3, 125 Bq.m-3 and 133 Bq.m-3, respectively. Between the ground and second floor of the apartment buildings, radon levels diminished by a factor of more than three which indicates that entry of radon-bearing soil gas was largely responsible for the higher concentration of radon in the ground floor. The radon levels in winter exceeded by approximately 30% the radon levels during summer. From the experimental data the equilibrium factor (F) and the effective dose equivalent (HE) were also obtained.