Dose reassessment method in thermoluminescent dosimetry by using the PTTL phenomena – A usefull tool

Introduction Reassessment of doses in film and OSL dosimetry is well known and standard method in contrary to TL dosimetry. By using the phototransferred thermoluminescence (PTTL) method which consist of the first readout, UV exposure and second readout it is possible to reassess doses in TL dosimetry. Purpose The PTTL method was developed and applied to reassess doses in whole body and ring dosimetry at Laboratory of Individual and Environmental Laboratory at IFJ PAN. Materials and methods Standard MTS-N (LiF: Mg, Ti) sintered thermoluminescent detectors (4.5 mm diameter and 0.9 mm thickness for whole body dosimeters and 0.7 mm thickness for ring dosimeters) have been applied. Some of them were used in routine control since 12 years. The TL detectors were read in automatic RE200 (Rados Oy, Finland) readers. After readout the PTTL method was applied. Detectors were subjected to UV radiation (254 nm length) and read once again in a reader. Results The PTTL method was applied to dose reassessment in individual and ring dosimetry. The reassessed doses are observed to be linear over the dose range 5–100 mSv in whole body dosimetry and 5–1000 mSv in ring dosimetry. Conclusion Due to checking behavior of different batches and different dose history it is possible to observe influence of residual dose to the PTTL effect. By using the PTTL method it is possible to reassess doses in whole body and ring dosimetry.