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A new regulatory statement was issued concerning the eye lens radiation protection of persons in planned exposures. A debate was raised on the adequacy of the dosimetric quantity and on its method of measurement. The aim of this work was to establish the individual monitoring procedure with the EYE-D™ holder and a MCP-N LiF:Mg,Cu,P thermoluminescent chip detector for measuring the personal dose equivalent H p (3) in workers of a Positron Emission Tomography Radiopharmaceutical Production Facility., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Since 2003 the Institute of Nuclear Engineering in Rio de Janeiro city, Brazil, operates a new cyclotron, RDS-111, to produce (18)F-Fluorodeoxyglucose to be used in nuclear medicine. Additionally, the IEN radioactive waste repository has been enlarged during the past last years, receiving a considerable amount of radioactive materials. Therefore, it became necessary to evaluate a possible increase of the environmental gamma exposure rates at the institute site due to the operation of the new accelerator and the enlargement of the institute waste repository as well. LiF:Mg,Cu,P, TLD-100H, and TL detectors were employed for environmental kerma rate evaluation and the results were compared with previous results obtained before the RDS-111 operation initialisation and the enlargement of IEN waste repository. No significant contribution for the enhancement of environmental gamma kerma rates was detected.

Optically stimulated luminescence (OSL) has become the technique of choice in many areas of dosimetry. Natural materials like topaz are available in large quantities in Brazil and other countries. They have been studied to investigate the possibility of use its thermoluminescence (TL) properties for dosimetric applications. In this work, we investigate the possibility of utilising the OSL properties of natural Brazilian topaz in dosimetry. Bulk topaz samples were exposed to doses up to 100 Gy of beta radiation and the integrated OSL as a function of the dose showed linear behaviour. The fading occurs in the first 20 min after irradiation but it is <6% of the integrated OSL measured shortly after exposure. We conclude that natural colourless topaz is a very suitable phosphor for OSL dosimetry.

In the present work, systematic dating by luminescence methods has been done on 50 Quaternary geological samples within the study area of São Paulo State, Brazil. Bleaching experiments showed that residual TL intensity of 375 degrees C peak, of the quartz, was obtained after 10 h of sunlight exposition. Intensities decays of the 325 and 375 degrees C TL peaks can be fitted using second order exponential equation. Paleodose values were evaluated using regeneration methods with multiple aliquots. Samples dated indicate preliminary ages varying from 9 +/- 1 to 935 +/- 130 ka for colluvio-elluvial deposits, and from 17 +/- 2 to 215 +/- 30 ka for alluvial deposits of the study area. They cover four peneplained surfaces shaped during the Quaternary: I (1000-400 ka), II (400-120 ka), III (120-10 ka) and IV (10 ka until today), in decreasing order.

The impurity-related point defects and the dosimetry properties of quartz irradiated with gamma- and X-rays doses were investigated for natural crystals taken from different geologies. The specimens were initially irradiated with gamma particles from (137)Cs to determine the sensitivity and repeatability of thermoluminescence (TL) emission at approximately 503 K. The dose response was investigated in the range 1-20 mGy. The energy dependence was considered in the range 16-65 keV with X rays and with gamma rays from 137Cs and 60Co. It was found that quartz material from two geologies exhibit a linear relationship between TL intensities and absorbed doses with high angular coefficients. Its sensitivities are higher than that found for LiF TLD-100 dosemeters irradiated in the same conditions. The results were discussed in relation to pre-existing impurity contents and the formation of Al-hole centres.

Dyed polymethylmethacrylate (PMMA) detectors using yellow, red, blue and green colouring compounds, commercially available in Brazil, were originally developed and characterised using the optical absorption (OA) technique for gamma radiation, with the aim of obtaining a sensitive, useful, practical and cheap dosemeter for use in the quality control of industrial gamma radiation processing. In this work these detectors were evaluated for electron OA response, for use in the quality control of electron accelerator radiation processing. The studied parameters were the absorption spectra, dose-rate dependence between 2.66 and 45.22 kGy s(-1); dose response between 1.2 and 110 kGy; and energy dependence of response between 0.8 and 1.5 MeV electron energy.

The method of phototransferred thermoluminescence (PTTL), using CaSO(4):Dy pellets produced at IPEN as sensitive material, was used to detect the spread laser radiation inside the surgery room during refractive surgical procedures using ArF excimer lasers. The purpose of this work was to study the viability of performing the ultraviolet radiation (UVR) exposure detection of patients and the hospital's surgical staff during a refractive surgery. The CaSO(4):Dy pellets were positioned at different distances from the laser source inside the surgery room: patient's ( congruent with 0.15 m), surgeon's ( congruent with 0.5 m) and nurse's ( congruent with 1.0 m) foreheads, lateral ( congruent with 1.5 m) and back ( congruent with 4.0 m) walls. The measurements of PTTL were carried out at two different conditions: five surgeries, each one taking approximately 10 min, and during a period of 4 h (cumulative), when several operations were performed. The detectors positioned as far as 4.0 m from the UV laser source were sensitised, making the UVR detection feasible at large source-detector distances. The absorbed energy was detected in the range from 40 microJ to 30 mJ during a surgery. This result indicates that the method studied can be used to detect the spread UVR.

A dosimetric survey in paediatric radiology is currently being carried out at the paediatric units of two large hospitals in Rio de Janiero city: IPPMG (Instituto de Pediatria e Puericultura Martagão Gesteira, University Hospital of Federal University of Rio de Janeiro) and IFF (Instituto Fernandes Figueira, FIOCRUZ). Chest X-ray examination doses for AP, PA and LAT projections of paediatric patients have been obtained with thermoluminescent dosimeters (TLDs) and with use of a software package DoseCal. In IPPMG and IFF 100 patients have been evaluated with the use of the TLDs and another group of 100 patients with the DoseCal software. The aim of this work was to estimate the entrance skin dose (ESD) for frontal, back and lateral chest X-rays exposure of paediatric patients. For ESD evaluation, three different TL dosimeters have been used, namely LIF:Mg,Ti (TLD100), CaSO4:Dy and LiF:Mg,Cu,P (TLD100H). The age intervals considered were 0-1, 1-5, 5-10 and 10-15 years. The results obtained with all dosimeters are similar, and it is in good agreement with the DoseCal software, especially for AP and PA projections. However, some larger discrepancies are presented for the LAT projection.

A thermally stimulated exoelectron emission (TSEE) measuring system developed and constructed at IPEN was used to verify the feasibility of the use of Brazilian natural semi-precious stones, such as jasper. amethyst, agate (blue and rose) and quartz (rose and white) for gamma and X radiation detection. Its counting system consists of a 2pi windowless gas-flow proportional counter, and the heating system is formed by a temperature programmer that provides linear heating of the samples. The samples were tested in gamma and in X radiation beams and evaluated in relation to their main dosimetric characteristics, as TSEE glow curves, calibration curves and energy dependence. The TSEE results are compared with those of thermoluminescence. The results obtained show the usefulness of Brazilian natural stones as dosimetric materials, using the thermoluminescence and thermally stimulated exoelectron emission techniques.

The aim of the present work is to investigate the possibility of using the properties of the thermoluminescent emission (TL) of Brazilian natural topaz for dosimetric applications. Topaz is an aluminium fluorsilicate with general composition of Al2(SiO4)(F,OH)2 found with relative abundance in Brazil and in other parts of the world. Topaz from Santo Antonio do Jacinto, Minas Gerais. Brazil, was used in this work, in the form of pellets of topaz mixed with Teflon and composites made with topaz embedded in a glass matrix. The TL sensitivity was tested between 10(-4) and 10(4) Gy. The TL peak intensity increases with the dose before saturation, which occurs around 2 kGy. The peak intensity showed a strong dependence with radiation energy. The effect of visible light and the behaviour of the TL signals after successive irradiation-reading-annealing cycles are presented and discussed.