The γ irradiation of organic solutions of Cholesteric Liquid Crystals (CLC) leads to a decrease in the temperature at which CLC films made from these solutions change colours compared to films prepared from the unirradiated solutions. The decrease in the color transition temperature was found to be proportional to the absorbed dose. The proportionality coefficient can be varied by changing the solvent and the concentration of the solute thus making this system suitable for dosimetry over a large range (tens of Krads to tens of Mrads).