Assessment of radon-222 concentrations in buildings, building materials, water and soil in Jordan.

Monitoring of radon gas ((222)Rn) in Jordan was started in the early 1990s. Since then our radon group at Yarmouk University and others have carried out tens of studies that include measurements of indoor radon, radon in water, radon in soil and radon emanating from building materials. All major cities of Jordan had been surveyed, from the northern city of Irbid down to the southern port city of Aqaba. Most of these studies were carried out by using time-integrated passive radon dosimeters containing CR-39 solid-state nuclear track detectors. In addition to that, an active radon monitor was used to study the seasonal variation of (222)Rn in Al-Ruseifa that lies near abandoned phosphate mines and in Amman area. During such a study passive dosimeters were also used. The average radon concentrations in dwellings in Jordanian cities ranged from about 20 to 386 Bq/m(3) with the highest readings exhibited during the winter season around the town of Al-Ruseifa.