Calibration and performance of radiochromic dye dosimeters

Radiochromic Dye Dosimeters (Gafchromic DM-100) were used to measure the absorbed doses in liquid samples exposed to a 137Cs gamma-ray source. The initial calibration of commercially available radiochromic film was performed using a 60Co gamma-ray source. When exposed to gamma-ray doses of 0.5 to 200 kGy, a color change occurs which has an optical density proportional to absorbed dose. The optical density for the irradiated radiochromic film dosimeter was evaluated using a FWT-100 optical density reader. The dose range was up to 3,000 Gy. They were used for measurements of 60Co dose rates on sources in hot cells, measurements of dose rates on samples that came out of the reactor, and measurements of dose rates from spent fuel in that Advanced Test Reactor (ATR) canal. The reproducibility of the radiochromic dye dosimeter was also studied. The radiochromic film dosimeter may be used for accurately determining dose rates on samples where use of conventional health physics instrumentation is impractical. The radiochromic dye dosimeter can be used in nuclear power plants, accelerator facilities, and clinical applications in radiotherapy departments, for high radiation dose measurements