Figure 1. The map of Iran (the left hand side picture) and the Zanjan state (the middle picture). The orange area is the city of Zanjan and the bold points (dots) show the sampling sites

From

Measurement of Indoor Radon Concentration Levels and Effective Dose Assessment in the Zanjan City, Iran

Mohammad Nejatolahi, Farzad Mehrjo, Ali Sheykhi, Farzad Vaziri Alamdarlo

Journal of Environment Pollution and Human Health. 2015, 3(1), 1-3 doi:10.12691/jephh-3-1-1