Investigation on the suitability of natural sandstone as a gamma dosimeter

The suitability of sandstone for the gamma radiation dosimetry using thermoluminescence technique is investigated. Its properties are systematically studied utilizing atomic absorption spectrometry, measurements of natural and laboratory-induced blue thermoluminescence emission band, trap depths and storage effects. The emission of the natural blue-band exhibited broad peak at ∼315 °C. The thermoluminescence gamma dose response has a linear behavior over the dose range 1-50 Gy followed by sub-linearity at high dose level, with standard deviation in all cases less than ±9%. Trapping depths showed a closely spaced set of traps for both the natural and laboratory-induced glow curves. The variation in thermoluminescence signal over 1 week storage period at room temperature was not more than 7%. The thermoluminescence fading effects were explained by the localized transition model. From our results, it is possible to conclude that natural sandstone is a suitable material for accident and industrial dosimetric applications.