Taking into account a 21% outdoor occupancy factor based upon interviews with local people, the annual average effective dose rate for individuals was estimated as 0.298 ± 0.04 and 0.175☐.03 mSv y-1 by TLDs and survey meter, respectively. The mean annual gamma dose rates measured by TLDs and survey meter were found as 1.47☐.10 and 0.862☐.003 mGy y-1 respectively. To estimate the annual gamma doses, NaI(Tl) based survey data were used for one complete year following the deployment of the dosimeters. During three distinct two month time periods within the six month study period, all the installed dosimeters were exposed to outdoor environmental gamma radiations, retrieved and read out at Radiation Dosimetry Laboratory, Health Physics Division, PINSTECH laboratory, Islamabad. CaF2: Dy (TLD-200) card dosimeters were installed at height of 1 m from ground at fifteen different locations covering the entire Poonch division comprising of three districts. A study was carried out to measure outdoor environmental gamma dose rates using a NaI(Tl) based survey meter and thermoluminescent dosimeters (TLDs) in Poonch division of the Azad Kashmir, Pakistan.

Bicron surveyor 2000 manual