Ten years of radiation monitoring experiences using thermoluminescent dosimeters

The Health Physics Division of the Bhabha Atomic Research Centre, Bombay, has developed a simple TLD system and been using it for the last ten years in a variety of applications in Radiation Dosimetry. Dosimeters have been fabricated in a number of shapes to suit specific applications: finger and wrist PVC sachets, rigid metalbound strips, encapsulations in metal, glass PVC containers etc. Experiences have also been accumulated in the use of various phosphorus like CaF2, CaSO4 and LiF. Some of the highlights of their applications have been: (1) Environmental monitoring inside Bhabha Atomic Research Centre; Trombay (ii) population exposure evaluation in monazite areas of the Kerala sea-coast; (iii) pre and post-operational environmental radiation surveys around nuclear power stations; (iv) isodose mapping of panoramic irradiation facilities; and (v) estimation of radiation levels for reactor fuel handling and storage. Recently attempts have been made: (i) in routine personnel monitoring for occupational workers on same lines as the existing film badge service; (ii) in evaluating radiation levels around Plasma-Torch-Welding operations; (iii) in the estimation of UV radiation levels in gas-welding operations; and (iv) in participating in the TLD intercomparison programme organised by the University of Texas. Results of these are also presented and discussed. (author)