Experimental study of dosimetric properties of radiophotoluminescent glass dosemeters using high-energy X-rays

This study evaluates the dosimetric performance of GD-302M radiophotoluminescent glass dosemeters (RPLGDs) under high-energy X-rays (6-15 MV) as a potential alternative to thermoluminescent dosemeters for radiotherapy audits in China. Key properties-dose linearity, uniformity, reproducibility, energy response, fading, build-up effects, and signal depletion-were systematically assessed using a medical linear accelerator under reference conditions. The results demonstrated excellent dose linearity (R2 = 0.9987, 1-4 Gy), uniformity (coefficient of variation = 0.9%), and reproducibility (standard deviation = 0.42%). Energy-dependent variations remained within 1.3%, while fading effects showed a cumulative signal loss of 3% over 110 d. Unpreheated RPLGDs retained 98% of preheated signals after 30 d, with minimal signal depletion per readout (0.016%). A water-to-solid phantom conversion coefficient of 0.998 was established. The total experimental uncertainty was 2.4%. These findings validate RPLGDs as a stable, reproducible, and cost-effective tool for enhancing radiotherapy quality assurance in resource-constrained settings.