Effects of glass and backscatter on measurement of absorbed dose in polyacrylamide gel (PAG) dosimeters

Different methodologies are used for calibrating polyacrylamide gel (PAG) d osimeters. One methodology involves injecting nitrogen-filled glass vials w ith polymer gel. Due to the vials being pre-filled with nitrogen, a nitroge n-filled space remains in the glass vial above the gel. The glass vial is t hen irradiated using ionizing radiation to polymerize the PAG. Monte Carlo simulations were performed to examine the effects on the radiation field du e to the glass vial and the lack of backscatter material due to the nitroge n-filled space. Results for two different formulations of PAG indicated tha t the influence of the glass and the nitrogen-filled space are negligible.