Abstract
This paper describes measurements of external gamma radiation average dose rate from terrestrial gamma rays 1 m above the ground in three different mountainous locations in the western region of the Kingdom of Saudi Arabia. These locations are, At-Taif city, Al-Hada village and Ash-Shafa village. CaSO(4):Dy (TLD-900) thermoluminescence dosemeters were used for the detection of terrestrial gamma radiation at 40 different places in the three locations. The values of terrestrial gamma radiation average dose rate measured ranged between 14 and 279 nG h(-1) for the time interval from June 2001 to June 2002. The measured average dose rate varied with the season of the year. The gamma radiation average dose rates were 468, 541 and 781 microGy y(-1) for At-Taif city, Al-Hada village and Ash-Shafa village, respectively. The corresponding average effective dose rates for the three locations were 94, 108 and 156 microSv y(-1), respectively.