In view of the complexities involved in estimating individual organ doses in positron emission tomography, the present study was undertaken to measure radiation surface doses in 23 patients undergoing PET studies using specially designed CaSO4: Tm TL dosimeters. In patients with brain disorders, the mean radiation surface doses to the chest and gonads were 0.52 mGy and 0.47 mGy, respectively. In patients with cardiac disorders, the mean surface doses to the forehead and gonadals were, respectively, 0.29 mGy and 0.41 mGy. It was possible to measure the radiation surface doses to all the intended sites in patients with liver malignancies, and maximum surface doses of 0.50 mGy and 0.49 mGy were recorded at the chest and gonadals, respectively. The measurement of radiation surface doses enables easy, quick, and reliable intercomparison of radiation load to patients and staff in various PET procedures.