The control of background in the production of TL dosemeters

As ALARA becomes more and more real in personnel dosimetry, TL dosemeters have assumed the role of low level detectors. While, for earlier years, intrinsic backgrounds were considered a necessary part of the dosemeter, identification and control of background sources is presently an important part of TLD technology. Typical radioactive interferences have been identified for starting chemicals for calcium fluoride. Screening methods have been devised with quantitative limits which are related to dosemeter performance criteria. Residual strain and radiation exposure also produce both fixed backgrounds and background rates. The time and temperature dependence of the interferences have been reviewed and methods for minimising their magnitude devised. (author)