Experience with phosphate glass dosemeters in personal and area monitoring

After the pattern approval of the German National Laboratory (PTB) modern photoluminescence dosimetry (PLD) systems have been used for more than 4 years in routine monitoring. In contrast to other dosemeter types of the one-element PL dosemeter SC-1 allows the simultaneous indication of the dose quantities Hx and Hp(10) based on the calibration exposure free-in-air and on the surface of an ISO slab phantom, respectively, in the energy range 10 keV-10 MeV with a coefficient of variation of about 1% at 1 mSv. For the measurement of H*(10) in area monitoring the energy compensation filter was slightly changed in the dosemeter SC-2. The long-term experience with the new FGD-10 readout system and the flat FD-7 glass dosemeter is discussed with respect to the reader calibration, the long-term stability of the readout and the lowest detectable dose. In routine monitoring at nuclear power plants, monthly results of the PLD system and of electronic dosemeters have been found to be consistent and also comparable in the dose range of 10 μSv. At annual PTB intercomparisons, the coefficient of variation was found to be 6% compared to about 12% for TLD systems. For area monitoring film and glass dosemeters have been used at five different X rays tubes applied in medical diagnostics. In general, the PLD system appears to be one of the most stable dosemeter systems for an application in all fields of personnel and area monitoring. (author)