Natural radioactivity due to radon in Soum region, Jordan

Abstract Indoor and in soil radon levels were measured using closed- and open-can techniques. Measurements were carried during three different seasons (fall, winter and spring) in Soum area northwest of Jordan. The highest average radon concentrations indoor were measured during winter, while in fall and spring its values were almost equals. The average radon concentration was 144 Bq m −3 , which is below the indoor radon concentration action level recommended by ICRP. This indoor average is about three times the Jordanian national average which may be due to the geological settings of the study area that composed of carbonate sedimentary rocks bearing high radioactive material. The average radon concentration in soil air was about 15 kBq m −3 and it ranges from 4 to 21 kBq m −3 in winter and fall, respectively. Ignoring other sources of radon in the dwellings, every 1000 Bq m −3 in the soil contributes about 10 Bq m −3 . The equilibrium factor was calculated to be 0.4.