YED poly(vinyl butyral) (PVB) film, prepared by a simple technique of casting aqueous solutions of PVB containing a mixture of brilliant green (BG), bromo phenol blue (BPB) and chloral hydrate (CCl 3 CH(OH) 2 , on a horizontal glass plate are useful as routine high-dose dosimeters. This flexible plastic film changes its colour from green to pale yellow to colourless on exposure to γ-rays photons due to the consequent lowering of pH caused by HCl generated from the radiolysis of chloral hydrate.

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... The useful dose rang extends up to 60 kGy. Effect of different chloral hydrate concentrations on response of the film was investigated. Although the film gives excellent stability before and after irradiation when stored in the dark at room temperature beside excellent stability up to 80% relative humidity (RH). The overall combined uncertainty (at 2σ) associated with measurement of response (ΔA.mm -1 ) at 634 nm for dose range 1-60 kGy is 5.63%.