FEASIBILITY STUDY FOR IDENTIFICATION OF STATIC AND DYNAMIC EXPOSURE USING CCD IMAGING TECHNIQUE FOR CaSO_4:Dy TL DOSEMETERS

摘要

The occupational exposure incurred by the radiation workers due to the external radiation is estimated using personal dose-meter placed on the human body during the monitoring period. In certain situations, it is required to determine whether the dosemeter alone was exposed accidentally/intentionally in radiation field (static exposure) or was exposed while being worn by a worker moving in his workplace (dynamic exposure). The present thermoluminscent (TL) based personnel monitoring systems are not capable of distinguishing between the above stated (static and dynamic) exposure conditions. The feasibility of a new methodology developed using the charge coupled device based imaging technique for identification of the static/dynamic exposure of CaSO_4:Dy based TL detectors for low energy photons has been investigated. The techniques for the qualitative and the quantitative assessments of the exposure conditions are presented in this paper.