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We report results of measurements of Hp(10) from whole body dosimeters (about 53 thousand readouts), of Hp(0.07) from finger ring dosimeters (23 thousand readouts) and of Hp(3) from eye lens dosimeters (100 readouts), issued in the years 2010-12 to over 150 medical departments in Poland which apply X-rays in radiology, interventional radiology (haemodynamic, angiology, cardiac surgery), urology, orthopaedics, electrophysiology or electro-cardiology. In all measurements thermoluminescence detectors (TLD) were used: the well-known standard MTS-N (LiF:Mg, Ti) for whole body and extremity dosimetry, and the high-sensitivity MCP-N (LiF:Mg, Cu, P) for eye lens dosimetry and environmental monitoring. We analysed the data base of the accredited Laboratory of Individual and Environmental Dosimetry (LADIS) at the Institute of Nuclear Physics PAN which offers its dosimetry service to these departments on a regular basis. We found that in the population of radiation workers that studied over the years 2010-2012 in 84%, 87%, and 34% of Hp(10), Hp(0.07) and Hp(3) measurements, respectively, the level of 0.1 mSv/quarter did not exceed, indicating lack of their occupational exposure. In the remaining 16%, 13% and 66% of individual cases, the 0.1 mSv/quarter exceeded, occasionally reaching several hundreds of mSv/quarter. [ABSTRACT FROM AUTHOR]

Abstract: Numerical dating using luminescence methods is widely applicable in geology, geomorphology, paleogeography and in archaeology for establishing ages of sediments and archaeological artefacts. Their popularity and versatility come from the fact that quartz and feldspar are ubiquitous minerals in the natural environment. Both of the luminescence methods, thermoluminescence (TL) and optically stimulated luminescence (OSL), have been widely used for dating loess in the past in Poland. Although OSL has certain advantages over TL dating in sedimentary environments such as loess, this method has been widely applied only in recent years. TL results obtained for Polish loess sections allowed creation of the Polish loess chronology in the 1980s. All luminescence dating results from laboratory intercomparison for loess profiles are presented here. [Copyright &y& Elsevier]

Abstract: MTS-N detectors are pellets of LiF:Mg,Ti produced at the Institute of Nuclear Physics (IFJ) in Krakow, Poland. The thermoluminescence (TL) response of these detectors to gamma radiation doses up to 10 kGy only has been studied earlier. The aim of this paper is to evaluate the TL and EPR response of MTS detectors irradiated with 60Co gamma radiation at high doses up to 1200 kGy. The results indicate that the MTS-N glow curve presents a new peak at temperature near 420 °C for doses over 700 kGy. This peak is probably associated with the second EPR signal that appears for doses over 100 kGy. The defect center related to this signal is undergoing further studies. [Copyright &y& Elsevier]

Abstract: BGO crystals have been grown using the Czochralski method by the West Pomeranian University of Technology in Szczecin, Poland. We report the measurements of scintillation yield and low temperature thermoluminescence, performed on polished 2×2×10mm3 pixel and 2×2×2mm3 cube samples. The yield of the pixels placed horizontally on the PMT window, as well as of the cubes, is about twice higher than the yield of the pixels placed vertically. Such a distinct light loss is interpreted in the frame of a simple two-ray model, describing quantitatively the scintillation yield of pixel samples depending on the measurement geometry. Related to this effect, the common overuse of “BGO units” for expressing the light output of any scintillator is discussed. Thermoluminescence glow curves consist of several peaks attributed to the existence of traps, which turn out to be responsible for a slight decrease of the scintillation yield measured at room temperature in a short time window. To improve the performance of BGO crystals, efforts should be aimed at reducing both the internal light losses and the trap concentration, with the main emphasis laid on the former. [Copyright &y& Elsevier]

Loesses cover a large area in SE Poland so their exploration is an important part of the palaeogeographical studies on Pleistocene. The research involves stratigraphic problems. At present, luminescence dating provides the greatest number of chronostratigraphic data concerning loesses. In this work we report TL ages of loesses from the last two glacial cycles in SE Poland, obtained in the TL Laboratory of the Department of Physical Geography and Palaeogeography, Maria Curie-Sklodowska University in Lublin after 1993. Samples for TL dating were collected in 11 bess profiles (2-9 samples in each site) in order to obtain additional information for stratigraphic interpretations deduced from paleopedobogical, lithological, structural, and other data. Basing on the comparison of 54 TL ages, we can determine age intervals, in which the dating results of similar values assemble, and then get general information about the periods of intensified Aeolian accumulation related to defined stratigraphic units. The TL ages of all samples were obtained using the total-bleach method (TB) for the determination of the equivalent dose. [ABSTRACT FROM AUTHOR]

The behavior of various TL dosimeters following two different thermal treatments with temperature ranging between 50 and 230 °C, was investigated in this particular study. The thermal treatment consists of two different protocols, including a simultaneous irradiation-heating and a post irradiation heating. The dosimeters that are the subject of the present study include two different families of lithium fluorides, namely the Harhsaw LiF family (TLD-600, TLD-700), LiF of the Krakow university (MTS-600, MTS-700), BeO and the commonly used CaSO 4 samples with two different impurities (Dy and Tm). According to the analysis, it seems that the TLDs and MTS-600 are identical with regard to their characteristics, while MTS-700 is different. The treatment showed that the intensities of peak 5 of all LiF samples increases up to 20–30% at 110 °C which is followed by a decrease, while the high temperature peaks of LiF showed a high dependence on the treatment temperatures. As for the case of BeO, one peak has a minor increase of 10% at 80–90 °C and a decrease up to 230%, while the other is stable. CaSO 4 samples show no increase and there is a decrease starting at 150 °C. Also, this work studied the kinetic parameters of all peaks for these samples via the computerized glow curve deconvolution method. In the end, there is a categorization of the LiF samples based on their properties and their glow curves. Lastly, the results indicate that the lack of strong increase of the TL response with increasing irradiation temperature for the majority of the TL peaks of these aforementioned phosphors does not support strong competition effects. A notable exception is observed for the high temperature TL peaks in all LiF samples regardless of whether these were purchased from Harshaw or from Poland. • The dependence on the temperature is different between the two protocols. • The high temperature peaks of the LiF samples follow strong competition effects. • Peak 5 of LiF and peak 2 of BeO do not follow strong competition effects. • The LiF samples can be categorized in two groups. • CaSO 4 samples show no increase in intensity through the thermal treatment. [ABSTRACT FROM AUTHOR]

It has been seven years from the ICRP Statement on tissue reactions containing the recommendations for an equivalent dose limit for the lens of the eye of 20 mSv per year for workers (ICRP, 2012), and has been 7 years since Laboratory of Individual and Environmental Dosimetry (LADIS) introduced in practice eye lens doses measurement. The reduction of the limit for occupational exposure for the lens of the eye needs adequate approaches for eye protection and eye dose monitoring. The most accurate method for monitoring the equivalent dose to the lens of the eye is to measure the personal dose equivalent Hp(3) with a dedicated dosimeter worn as close as practicable to the eye. To measure eye lens doses in terms of this quantity a dosemeter and an appropriate method has been introduced in the largest dosimetry service in Poland. This paper presents historically the introduction of eye lens dosimetry in routine measurements and an analysis of the exposure results of the eye lens dose sl. Results of measurements of Hp(3) from eye lens dosemeters (almost 5000 quarterly readouts), issued in the years 2012–2018 were reported. In measurements EYE-DTM dosemeter developed within ORAMED EU project (Vanhavere et al., 2011) and high-sensitivity MCP-N (LiF:Mg, Cu, P) thermoluminescence detectors were used. The frequency distribution of eye lens dose measurements performed using specially dedicated dosemeters, via their Hp(3) operational values, over 3-month periods, after subtraction of natural background in 74% cases are below 0.1 mSv. In the case of the new operational quantity, Hp(3) the number of workers, which exceed the new limit during 7 years monitoring period was 48 (1%). The study showed considerable uncertainties associated with the assessment of eye lens dose from the commonly used whole body dosemeters on the chest in terms of Hp(10) and ring dosemeters on the finger which measures skin doses in terms of Hp(0.07). Therefore, only monitoring of the eyes with specific dosemeters for yearly follow-up can provide accurate annual doses. • Improvement of eye lens dosimetry to interventional radiology and cardiology staff and to nucelar medicine. • The obtained dosimetry data could be used for epidemiological studies to assess retrospectively eye lens dose. • 5000 Readouts of eye lens doses are presented. [ABSTRACT FROM AUTHOR]