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The individual monitoring service Seibersdorf uses two different passive dosemeter types based on thermo luminescence (TL) detectors for monitoring occupationally exposed persons in Austria. Whole body personal dosemeters for the personal dose equivalent quantities H p (10) and H p (0.07) worn on the trunk and dosemeters for the extremities for H p (0.07) worn on a finger or wrist. Both routine dosemeters were calibrated and tested in terms of the personal dose equivalent H p (3) assuming that the whole body dosemeter is worn on the chest (without or above a lead apron) and the modified ring/wrist dosemeter using a special strap worn on the forehead near the eyes (head band dosemeter). The test results show that it is possible to measure the dose quantity H p (3) with these dosemeters that were originally not designed for this dose quantity. Only changes in the dose calculation algorithm and in the choice of the reference radiation quality were necessary to fulfil the requirements given in international standards for passive dosemeters in a wide energy (20 keV–1.3 MeV) and angular range (0°–60°).

At the accredited PSI Calibration Laboratory neutron reference fields traceable to the national standards of the Physikalisch-Technische Bundesanstalt (PTB) in Germany are available for the calibration of ambient and personal dose equivalent (rate) meters and passive dosimeters. The photon contribution to the ambient dose equivalent in the neutron fields of the 252Cf and 241Am–Be sources was measured using various photon dose rate meters and active and passive dosimeters. Measuring photons from a neutron source usually involves considerable uncertainties due to the presence of neutron induced photons in the room, due to a non-zero neutron sensitivity of the photon detector, and last but not least due to the energy response of the photon detectors. Therefore eight independent detectors and methods were used to obtain a reliable estimate for the photon contribution of the two sources as an average of the individual methods. For the 241Am–Be source a photon contribution of approximately 4.9% was determined and for the 252Cf source a contribution of 3.6%.

Dosimetry studies are of increasing interest in diagnostic high-dose applications such as computed tomography especially for examinations of children. A routine CT scan protocol for paediatric head and neck imaging was investigated at a new multi-detector CT scanner using LiF:Mg,Cu,P thermoluminescence dosemeters (TLDs) and a 0.125 cm3 thimble ionization chamber. Calibrations of the detectors in terms of absorbed dose to water were carried out at the Dosimetry Laboratory Seibersdorf in standard radiation fields. The dosimetry method was validated in the spiral CT X-ray field by comparing TLD and ionization chamber measurement results in cylindrical PMMA phantoms. Absorbed dose results were within stated uncertainties. An anthropomorphic phantom representing a child of about 5 years was loaded with TLD chips at various organ and tissue positions in the head and neck region as well as at some critical organ locations. Organ dose values were calculated from TLD based average absorbed dose with about 5% total uncertainty, e.g. 22 mGy (eyes), 21 mGy (thyroid), 19 mGy (brain), 3.4 mGy (thymus), and 0.03 mGy (testes). For comparison purposes an effective dose of 1.9 mSv was estimated for the investigated paediatric CT examination based on ICRP-103 age-independent tissue-weighting factors.

The energy and angular response of the MTS-N (LiF:Mg,Ti) and MCP-N (LiF:Mg,Cu,P) TL detectors inside the RADOS personal dosemeters to X-rays photons in the energy range 16–250 keV and incidence angles 0°, 30°, 40°, 50°, ± 60 ∘ and 137 Cs and 60 Co sources was measured. The irradiations were performed at the Dosimetry Laboratory of the Austrian Research Centers Seibersdorf. The dosemeters were centered on the front surface of the ISO water slab phantom ( 30 × 30 × 15 cm 3 ) and irradiated with reference photon radiation qualities N (the narrow spectrum series), and S–Cs and S–Co nuclide radiation qualities, specified in ISO 4037 (1999) . In addition, the energy response to photons of the dosemeter with MCP-N detectors has been calculated using the Monte Carlo transport code MCNP5. The simulation model of the personal dosemeter badge was set up according to the technical drawings. The results of simulations are in good agreement with measurements, except at the lowest (16 keV) photon energy. The results have confirmed that the RADOS personal dosemeter with MTS-N detectors (used by LADIS dosimetry service of the IFJ, Krakow) fulfils the requirements setup in the IEC 61066 (2006) technical recommendations for TL systems for personal dosimetry. These requirements are also fulfilled by the RADOS dosemeter equipped with highly sensitive MCP-N detectors.

This paper presents the results of a comparison of four different dose algorithms used for evaluating a two element TL routine whole body dosemeter. Due to the energy response of LiF:Mg,Ti detectors a dose algorithm is applied to assess the relevant dose over the rated energy range with an acceptable energy response. The discussed dose algorithms are designed to calculate the dose in terms of three different dose quantities. The first two algorithms are used to evaluate the dose quantity photon dose equivalent H x . This quantity was the legal quantity in Austria and Germany for the last decades. The other two algorithms are designed for reading out the dosemeter in terms of the dose quantities personal dose equivalents, H p (10) and H p (0.07). A huge number of individual dose values are recalculated and compared by statistical methods. In addition all dose values are analysed with respect to the ratio of the two detector readings which adds some spectral information to the dose values. This allows estimating the radiation quality (photon energy) for the different dose values.