M.S. Thesis Presentation by Neale Jeff Griffis
Wednesday, July 11, 2001

(Drs. Rod Ice and John Valentine, co-advisors)

"Performance Evaluation of the Dosicard Electronic Personal Dosimeter"

Abstract

Application of radioactive material in industrial, medical, and research fields has become widespread. Because of the hazards involved with radioisotopes, it is necessary to closely monitor radiation dose to workers using these materials. Thus, worker dosimetry has become an important element of radiation protection programs. Advances in recent technology have resulted in lightweight, powerful electronic personal dosimeters (EPDs) for use in active monitoring of personnel. The Dosicard, manufactured by Eurisys Mesures, is one of these advanced EPDs. The Dosicard is a credit-card sized EPD that quantifies worker dose from gamma- and x-ray photons. It operates with a silicon diode detector to provide real-time dose monitoring of workers, and includes extensive memory features to permanently store worker dose information. Before acceptance for use at the Georgia Institute of Technology, the Dosicard's radiological performance was to be evaluated. This performance evaluation of the Dosicard included tests to examine its accuracy, angular response, photon energy dependence, and precision. Feasibility and cost benefits of implementing the Dosicard system were also briefly reviewed.

In all, the Dosicard's radiological performance met criteria of national standards for EPDs. Dosicard accuracy was found to fall between +/- 15% at dose/dose rates within its sensitive range. Dosicard angular response was observed to be within +/- 20%. Dosicard photon energy-dependence was found to be less than +/- 15% over an energy  range of 60 keV to 1.25 Mev. Finally, the Dosicard's precision was observed to show a variance of < 5% for repeated identical measurements. These results present the Dosicard as an eligible EPD for use in health physics monitoring at the Georgia Institute of Technology.