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

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