Suitability of gafchromic EBT2 films for dosimetry of low gamma–rays

Radiochromic film has become an important tool to assess complex dose distributions. As a self–developing film, EBT2 is a perfect fit for the processor–less environment. Radiation dosimeters based on EBT2 containing active layer, marker dye (coded) and stabiliser have been prepared. EBT2 films undergo radiation when subjected to gamma rays inducing change in the absorption spectra in the film which converts from faint green to deep green peaking at 631 nm, and upon irradiation the new developed peak and their amplitudes with the original peak increase with the increase of absorbed dose. The useful dose range of this film is 1 cGy to 15 Gy. So it can be used as a dosimeter in the field of blood irradiation and radiotherapy. The effect of relative humidity during irradiation on the response of films as well as pre– and post–irradiation stability at different storage conditions was described.