Reference

Incompatibility of sensitization and re-estimation of lithium fluoride thermoluminescent phosphor

Incompatibility of sensitization and re-estimation of lithium fluoride thermoluminescent phosphor. Bartlett, D. T.; Sandford, D. J. (Natl. Radiol. Prot. Board, Harwell/Didcot/Oxon., Engl.). Phys. Med. Biol., 23(2), 332-4 (English) 1978. CODEN: PHMBA7. ISSN: 0031-9155. DOCUMENT TYPE: Journal CA Section: 71 (Nuclear Technology) Results obtained on annealing-sensitization of LiF [7789-24-4] dosimeters (TLD 700) indicate that for routine personnel dosimetry, the disadvantage of the loss of the capability of these dosimeters to re-est. absorbed dose outweighs the advantages of sensitization by annealing.

Long-term recycling characteristics of lithium fluoride (TLD-100) dosimeter material

Long-term recycling characteristics of lithium fluoride (TLD-100) dosimeter material. Wald, J.; DeWerd, L. A.; Stoebe, T. G. (Dep. Min., Metall., Ceram. Eng., Univ. Washington, Seattle, Wash., USA). Health Phys., 33(4), 303-10 (English) 1977. CODEN: HLTPAO. DOCUMENT TYPE: Journal CA Section: 71 (Nuclear Technology) Changes in the sensitivity of LiF [7789-24-4](TLD-100) dosimeters subject to std. 400° annealing treatments for up to 100 cycles were investigated. Results indicate that for extruded ribbon dosimeters cycled through a 1-h, 400° anneal, the resulting thermoluminescent sensitivity decreases as the no. of cycles increases. The max. effect is seen in samples exposed to 1 R of 137Cs irradn. between cycles, which for annealing in air causes a decrease of about 6% after 50 cycles, accelerating to nearly a 15% decrease in sensitivity after 100 cycles. Samples not exposed to irradn. between cycles show a smaller resultant sensitivity decrease. Comparison of the TL response of samples annealed at 400° for 100 1-h cycles to those annealed at 400° for 2 50-h cycles shows a smaller decrease in sensitivity after the 2 50-h anneals. This indicates that the cause for the obsd. behavior lies in the heating and cooling process itself, rather than in the time at temp. Further comparisons between extruded ribbon and single crystal samples and between samples annealed in air, Ar or vacuum are also presented. For routine dosimetric use with the std. 400° anneal cycle, a max. reuse of 50 times is recommended.