The use of polyvinyl chloride films dyed with methyl red in radiation dosimetry

Background: The purpose of this work was to investigate the use of polyvinyl chloride (PVC) dyed with methyl red as a high dose radiation dosimetry. Materials and Methods: Commercial PVC films from Sabic made from resins PVC57S with thickness of 60 mu m and methyl red with a molecular weight of 269.31 were used. Irradiation was carried out using a Co-60 y-ray generator with sources arranged in rectangular holder with a total activity of 73.6926 kCi. Absorbance measurements were made by Jasco V- 630 UV-VIS spectrophotometer. Dose rate and irradiation temperature effects as well as post-irradiation storage in dark and indirect daylight conditions on dosimetry performance were also investigated. Results: The results showed a linear relationship between the relative absorbance (response) and the absorbed dose at the wavelength 548 nm in the range of 0-150 kGy. The response was found to be independent of both dose rate and irradiation temperature. Conclusion: The experimental results indicate that PVC films dyed with methyl red may be used for a high dose radiation dosimetry.