Dosimetric evaluation of high-density polyethylene (HDPE) as a dosimeter for high dose-dosimetry

This work reports the possibility of using high-density polyethylene (HDPE) as a dosimetric material for gamma-radiation measurements. For this purpose a commercially available, thin plastic film (mean thickness 1 mm) of HDPE, having a transparent white color was used. Gamma-ray radiation induces the formation of free radicals in HDPE that can be detected and measured by electron paramagnetic resonance (EPR). An increase of the EPR-signal response for the free radicals produced in the sample was observed as a function of the irradiation dose. This way the EPR-signal response of gamma-irradiated HDPE has been investigated to determine some of its dosimetric characteristics such as: peak-to-peak signal intensity versus gamma dose received, zero-dose response, detection threshold, signal repeatability, batch homogeneity, signal fading and stability at different environmental conditions such as, relative humidity and simulated sunlight exposure. It is concluded that HDPE might be used as a high-dose dosimeter (20-2000 kGy), with a very good reproducibility. (Author)