The Purpose of this study was to evaluate reproducibility and linearity according to change of exposure condition of GD in diagnostic X-ray, and compare the dose change and build up characteristic according to delay time in 30 days of glass dosimeter processed preheat and non preheat when measuring accumulation dose of radiation by using glass dosimeter over the long term. The glass dosimeter (AGC Techno Glass Co, Japan) we used, was SC-1 with 30 mm × 40 mm × 9 mm, rectangle shaped and capable of measuring and X-ray. In experiment first which is dose evaluation according to changed tube voltage, sixty GD''s were divided twenty GD''s into three groups (50 kVp, 80 kVp and 100 kVp). Then, each groups of GD were exposured and evaluated. In experiment second which is dose evaluation according to changed tube current, twenty four GD''s were divided twenty GD''s into six groups (5 mAs, 10 mAs, 16mAs, 20 mAs, 25 mAs and 32 mAs). Then, each groups of GD were exposured and evaluated. In experiment third, for obtaining low dose with 0.1 mGy, 1 mGy and 5 mGy, we employed diagnostic generator AccuRay-650R. We compared the build up characteristic over the long haul by exposuring radiation to 30 glass dosimeters sorted into 10 glass dosimeters per tube voltage and current. In non preheat glass dosimeter, initial measured dose was inferior to exposed dose but as time goes on, was close to exposed dose steadily. In 72 hour after experiment end, non preheat glass dosimeters were not indicated the difference from preheat glass dosimeters and statistical analysis were meaningful (p>0.05). Initial measured dose for low glass dosimeter processed preheat was close to exposed dose and stable. After 15days dose was gradually increased. In dose characteristic evaluation of GD for evaluating dose in diagnostic X-ray, the GD is considered as dosimeter which is used not high energy but low energy. However, when reading the dose immediately, Preheat process should be performed in advance. In this study, we make a judgment to measure the dose of glass dosimeter without preheat processing when measuring the accumulation dose of low dose in conclusion.
key Words : reproducibility, linearity, preheat, non-preheat, glass dosimeter,