Gini Method Application: Indoor Radon Survey in Kpong, Ghana

In this study, the indoor radon concentrations map, starting from a sparse measurements survey, was realized with the Gini index method. This method was applied on a real dataset coming from indoor radon measurements carried out in Kpong, Ghana. The Gini coefficient variogram is shown to be a good estimator of the inhomogeneity degree of radon concentration because it allows for better constraining of the critical distance below which the radon geological source can be considered as uniform. The indoor radon measurements were performed in 96 dwellings in Kpong, Ghana. The data showed that 84% of the residences monitored had radon levels below 100 Bqm¯³, versus 16% having levels above the World Health Organization's (WHO) suggested reference range (100 Bqm¯³). The survey indicated that the average indoor radon concentration (IRC) was 55 ± 36 Bqm¯³. The concentrations range from 4–176 Bqm¯³. The mean value 55 Bqm¯³ is 38% higher than the world's average IRC of 40 Bqm¯³ (UNSCEAR, 1993).