25 YEARS OF TL DOSIMETRY AT THE INSTITUTE-OF-NUCLEAR-PHYSICS, KRAKOW

The first TL materials (LiF:Cu,Ag and CaF2:Mn) and a simple reader wer e developed at the INP in 1966 and used for dose measurements in radia tion protection and radiotherapy. Further developments of a reproducib le doping method of UF with Mg and Ti ions, and of a method of sinteri ng pellets (MTS-N or MTS-7) allowed several investigations to be perfo rmed and the application of these TL detectors in environmental and in dividual monitoring. The properties of MTS- and MCP-type materials wer e systematically investigated. Particular attention was paid to the no n-typical response of this last phosphor to radiations of different LE T which was investigated experimentally and theoretically. A broad pro gramme of investigations of the MCP phosphor with various activator co ntents allows its dosimetry properties to be optimised. For measuremen ts of doses of weakly penetrating radiation and of neutrons thin dosem eters of different construction were developed. Since 1968 MTS dosemet ers have replaced films in routine monitoring of individual doses of t he INP workers. Levels of natural gamma radation throughout Poland out doors and indoors and, in more detail, around several smaller area wer e investigated for several years using an automated TL system develope d at the INP. Systematic long-term monitoring of the dose rate of gamm a radiation at one site at the INP allowed us to observe seasonal dose rate fluctuations and to register coarse and subtle changes in the ba ckground dose rates after the Chernobyl catastrophe. A method of measu rement of radon daughters with the use of thin CaSO4:Dy pellets was de veloped and is now routinely used in Polish coal mines. Thin dosemeter s with enhanced Li-6 and Li-7 content were developed and are now used in an Albedo neutron dosimetry system which completes the comprehensiv e system of individual monitoring of INP workers.