Background variation and radiation-induced darkening of radiophotoluminescent detectors

Radiophotoluminescent (RPL) detectors are used extensively for measurement of γ, X and β radiations. While these detectors show excellent dosimetric properties, we point out behaviors observed in their routine use that can affect the accuracy of their results. There is a radiation-induced darkening of the detector and a background noise limit beyond which the impact of ionizing radiation on the measurement becomes unclear. Tests show that after several measurement-anneal cycles, the RPL detectors reach a threshold value of intrinsic background, which causes measurements of small doses to be unreliable.