Retrospective dosimetry for external exposures

• Published in: International Congress series 2002-02, Vol.1225, p.141-148
• Main Authors: Jacob, Peter, Göksu, Yeter, Meckbach, Reinhard, Wieser, Albrecht
• Format: Article
• Language: English
• Subjects: Bricks; EPR; OSL; Thermoluminescence; Tooth enamel
• ISSN: 0531-5131; 1873-6157
• DOI: 10.1016/S0531-5131(01)00541-6

Two methods of retrospective dosimetry for external exposures are reviewed. First, electron paramagnetic resonance (EPR or electron spin resonance, ESR) with teeth has its strengths in the determination of individual exposures, acute or protracted, that may have occurred several decades ago. The method is best studied for photon fields. The current detection limit is 100 mGy. Due to a higher sensitivity to photons with energies in the range of 30–100 keV, information of this spectral component is necessary to achieve a high accuracy. Second, luminescence methods including thermoluminescence (TL) and optical stimulated luminescence (OSL) have their strengths in determining absorbed dose in bricks or porcelain. A detection limit in the order of several tens of mGy is achieved if the mineral fraction of the brick is well suited for luminescence measurements. By measuring depth profiles of absorbed dose in a brick or height profiles over a wall, information on effective source geometry and photon energy may be obtained. Future perspectives of the methods include: (i) conversion of dose quantities measured as absorbed dose in enamel or bricks to absorbed dose in air and human organ doses; (ii) EPR measurements with milk teeth; (iii) in situ EPR measurements of teeth in the human mouth; and (iv) exploration of new materials for the luminescence method, especially those which are worn by people allowing to come closer to an individual dosimetry.