Retrospective dosimetry using unheated quartz: a feasibility study

Most attempts to apply retrospective dosimetry to building materials have made use of heated (sensitised) items such as brick or tile ceramic. Unfired materials, such as concrete, are far more widespread in the industrial environment, but unfortunately these cannot be assumed to contain a negligible dose at the time of construction. This paper reports on preliminary attempts to measure, using optically stimulated luminescence (OSL), a dose-depth profile in a new concrete brick which had been given a known dose in the laboratory. The dose distribution in individual samples was measured before and after irradiation using small aliquots each of 65 quartz grains, and also using single grains, extracted from the concrete. Despite the material being very poorly zeroed prior to irradiation, both approaches gave satisfactory results and it is concluded that measurement of individual grains from poorly zeroed building materials can provide useful information on accident doses.