Desiccants for retrospective dosimetry using optically stimulated luminescence (OSL)

• Desiccants can be used as fortuitous dosemeters using OSL.
• The minimum detectable dose for processed desiccants range from 8 to 450 mGy.
• The minimum detectable dose for natural clay was 1.8 Gy.

Optically stimulated luminescence (OSL) was used to test different kinds of desiccants for their potential use in retrospective dosimetry. Desiccants are used for the purpose of absorbing liquids and can be found in a number of items which may be found in the immediate environment of a person, including hand bags, drug packages, and the vehicles of rescue service teams. Any material exhibiting OSL properties suitable for retrospective dosimetry is a useful addition to the existing dosimetry system available in emergency preparedness. Eleven kinds of desiccants were investigated in order to obtain an overview of the fundamental OSL properties necessary for retrospective dosimetry. Measurements were made using a Risø TL/OSL reader and irradiations were achieved with the 90Sr/90Y source incorporated in the reader. Several of the desiccants exhibited promising properties as retrospective dosemeters. Some of the materials exhibited a strong as-received signal, i.e. without any laboratory irradiation, but the origin of this signal has not yet been established. The minimum detectable dose ranged from 8 to 450 mGy for ten of the materials and for one material (consisting of natural clay) the minimum detectable dose was 1.8 Gy.