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Jedan od zadataka projekta 16ENV04 Preparedness jeispitivanje pasivnih dozimetrijskih sistema namenjenih za merenje operativne dozimetrijske veličine H*(10). Cilj ovog zadatka je evaluacija i harmonizacija procedura koji koriste laboratorije u Evropi a odnose se na merenje ambijentlnog ekvivalenta doze,a u vezi eventualne primene ovakvih doziemtrisjkih sistema u kontekstu dleovanja u vanrednom događaju., One of the outstanding tasks of the project 16ENV04 Preparedness, is to investigate the use of passive dosemeters aimed for measurement of operational quantityH*(10). The aim of this task is to develop a rationale to harmonize the procedures used by European measuring bodies and authorities, which provide services or fulfil tasks in radiation protection by using passive H*(10) area monitoring systems. Procedures used by European measuring bodies and services for environmental monitoring using passive area dosemeters are investigated, with a goal to investigate the applicability of passive dosimetry systems in the aftermath of a nuclear event.

Sledeći rezultate epidemioloških studija o efektu jonizujućih zračenja na očno stočivo, Međunarodna komisija za zaštitu od zračenja revidirala je granicu izlaganja za očno sočivo, imajući u vidu da u slučaju dugotrajnog izlaganja malim dozama i malim jačinama doza na radnom mestu, katarakta može nastati na nivou doze daleko manjim od ranije utvrđenog praga. Ovakve situacije su tipične za profesionalna izlaganja u interventnoj kardiologiji i radiologiji. Cilj ovog rada je prikaz metodologije za donošenje odluke o potrebi za individualnim monitringom za očno sočivo i prikaz rezultata pilot monitoringa u interventnoj kardiologiji pomoću namenskih dozimetara za očno sočivo kalibrisanim u dozimetrijskoj veličini lični dozni ekvivalent Hp(3)., Following recent epidemiological evidences on effects of ionizing radiation to the eye lens, International Commission on Radiological Protection has re-evaluated dose limit to the lens of the eye, owing that protracted exposure to the relatively small doses and dose rates may lead to the cataract at dose levels much lower than previously set dose thresholds. Such satiations are typical for occupational exposure in interventional cardiology and radiology. Occupational exposure from interventional x-ray procedures is an area in which increased eye lens exposure may occur. Accurate dosimetry is an important element to investigate the correlation of observed radiation effects with radiation dose, to verify the compliance with regulatory dose limits, and to optimize radiation protection practice. The papers presents the overview of practical methods for eye lens doses assessment as well as typical occupational eye lens dose levels in interventional procedures in cardiology and radiology. In addition, a methodology to assist decision making about need for specific eye lens individual monitoring using a dedicated passive dosimeters calibrated in terms of Hp(3) is presented in this paper.

Za potrebe obuke lica za delovanje u slučaju hemijskih, bioloških, radioloških i nuklearnih akcidenata (HBRN) uspostavljena je platforma u okviru Instituta za nuklearne nauke Vinča (INNV). Na samoj platformi se između ostalih izvode praktična uvežbavanja: lociranja radioaktivnog izvora, obezbeđivanja izvora i različitih scenarija dekontaminacije. Jedna od nadležnosti Laboratorije za zaštitu od zračenja i zaštitu životne sredine (Zaštita) je da primeni odgvarajuće mere radi kontrolisanog izlaganja jonizujućem zračenju pojedinaca na platformi kao i radnika INNV. U ovom radu su prikazani rezultati merenja ambijentalnog ekvivalenta doze, H*(10) pomoću termoluminiscentnih dozimetara (TLD) koji su postavljeni u cilju monitoringa okoline tokom HBRN vežbe koja je izvedena u aprilu 2017. Merenja su vršena postavljanjem TLD na 22 lokacije na samoj platformi i van nje u trajanju od 14 dana. Izmerena srednja vrednost H*(10) iznosi 34 µSv za posmatrani period što pokazuje da nije došlo do značajnog povećanja ambijentalne ekvivalentne doze u odnosu na osnovni nivo prirodnog zračenja., For the purpose of professional responder training in the case of chemical, biological, radiological and nuclear accidents (CBRN), a training platform was established within the Vinca Institute of Nuclear Sciences (INNV). On the platform, among other things, practical exercises are carried out such as: locating radioactive sources, securing sources and various decontamination scenarios. One of the responsibilities of the Department of Radiation and Environmental Protection (Zastita) is to apply specific measures for the controlled exposure to ionizing radiation of individuals on the platform as well as of INNV workers. This paper presents the ambient dose equivalent H*(10), measured using thermoluminescent dosimeters (TLDs) that were set up to monitor the environment during the CBRN exercise in April 2017. The measurements were made by placing the TLD at 22 locations on the platform itself, and out of it for 14 days. The mean H*(10) is 33 µSv for the observed period, which shows that there was no significant increase in the ambient dose relative to the background level.

Manipulation of unsealed radiation sources in nuclear medicine (NM) departments involves non-uniform exposure to staff and high skin doses to the upper extremities from direct and scattered radiations. Conducted studies have shown that the annual dose limits could be exceeded and the continuous dose monitoring of NM workers hands is needed. The aim of this article is to show results of hand dose monitoring in terms of operational quantity H-p(0.07) for occupationally exposed NM workers to beta and gamma radiations in the largest NM centre in Serbia. Dose assessment was done by means of thermoluminescent ring dosemeters DXT-RAD (LiF:Mg,Ti). Monthly and annual doses were evaluated for a 5-y period (2010-14). Monitored NM staff was categorised according to the type of work, as nurses, radiographers, laboratory technicians and radiochemists. Performed evaluation showed that annual hand doses were within the annual limit for all staff categories, but further optimisation of working practice is needed.

The objective of this work is to assess the occupational dose in interventional cardiology in a large hospital in Belgrade, Serbia. A double-dosimetry method was applied for the estimation of whole-body dose, using thermoluminescent dosemeters, calibrated in terms of the personal dose equivalent H-p(10). Besides the double-dosimetry method, eye dose was also estimated by means of measuring ambient dose equivalent, H*(10), and doses per procedure were reported. Doses were assessed for 13 physicians, 6 nurses and 10 radiographers, for 2 consequent years. The maximum annual effective dose assessed was 4.3, 2.1 and 1.3 mSv for physicians, nurses and radiographers, respectively. The maximum doses recorded by the dosemeter worn at the collar level (over the apron) were 16.8, 11.9 and 4.5 mSv, respectively. This value was used for the eye lens dose assessment. Estimated doses are in accordance with or higher than annual dose limits for the occupational exposure.

The routine monitoring of the occupationally exposed individuals constitutes an integral part of radiation protection program implemented at the Vinca Institute of Nuclear Sciences (INNV). The Individual monitoring service (IMS) at the INNV, accredited according to quality standard EN ISO/IEC 17025, is using Harshaw 6600 Plus automatic reader and thermoluminescent dosimeters (TLD) from two manufacturers (Harshaw, RadPro international GmbH). Working procedures are implemented according to Technical Recommendations for Monitoring Individuals Occupationally Exposed to External Radiation, RP 160 (European Commission, 2009). Among general consideration, RP 160 is suggesting that routine calibration of dosimetry system should be performed taking into consideration secondary charged particle equilibrium. As TLD system in use at IMS INNV comprises of TLD reader and of TLD cards, this consideration should be applied in both cases: when the reader and the TLD cards are being calibrated. During reader calibration, secondary charged particle equilibrium can be ensured using build-up PMMA plate of certain thickness placed in front of dosimeters. In this paper, influence of the build-up plate on reader calibration is being analyzed. This influence is observed through changes in reader calibration factor (RCF). RCF values obtained during reader calibration procedure with and without 2 mm thick build-up plate are presented. Exposures of whole body TLDs placed on slab phantom were done with Cs-137 radiation source located at Secondary Standard Dosimetry Laboratory (SSDL) at INNV. TLDs from both manufacturers had 2 detectors for measuring the dose equivalent at the depths of 10 mm and 0.07 mm. TLD reader was calibrated to measure effective dose in terms of Hp(10) and local skin dose in terms of Hp(0.07). RCF values for detectors measuring Hp(10), from both manufacturers, when irradiated without the plate were around 5% higher than RCF values obtained when irradiations were done with

Pulse height distribution (PHD) registered by a spectrometer is influenced by various physical phenomena such as photon interactions as well as disturbance produced by the electronic circuits inside the spectrometer. Therefore, spectrometry measurements of gamma and X-ray radiation inaccurately represent primary spectra. In order to overcome spectrum disruption, spectrum unfolding has to be applied. One of the common tools used in the unfolding process is Monte Carlo simulation of spectrometer response to monochromatic photons. The purpose of this work is to develop a new method for simulating CdTe semiconductor spectrometer response to monochromatic photons that can be further used for the spectrum unfolding procedure. The method is based upon post-processing of the particle track (PTRAC) output file generated by the MCNP5 program. In addition to the spectrometry output, this method provides information for each specific photon interaction inside the spectrometer active volume, which is required when taking into account spectrometer charge collection. The PTRAC generated detector response and the measured spectrum were in good agreement. The results obtained showed that this method can be used to generate precise response functions of gamma and X-ray spectrometers.

Research activities of Vinca Institite have been based on two heavy water research reactors: a 10 MW one, RA, and zero power, RB. Reactor RA was operational from 1962 to 1982. In 2010, spent fuel has been sent to the country of origin, and the reactor now is in decommissioning. During the operational phase of the reactor there were no recorded accidental releases into the environment, only operational ones. Results of the environmental impact assessment of the assumed emission of radionuclides from the ventilation of nuclear reactor RA in Vinca to the atmospheric boundary layer are presented in this paper. Evaluation was done by using the Gaussian straight-line diffusion model and taking into account characteristics of the reactor ventilation system, the assumed emission release of radioactivity (from the literature), site-specific meteorological data for six-year period and local topography around nuclear reactor, and corresponding dose factors for inventory of radionuclides. Based on the described approach, and assuming that the range of appropriate meteorological data for six year period for the application of described mathematical model is enough for this kind of analysis, it can be concluded that the nuclear reactor RA, in the course of its work from 1962 to 1982, had no influence on the surrounding environment through the air above regulatory limits.

In this study, we point to loss of accuracy in representing a field of air pollution concentration due to reduction of number of monitoring points or changes in their location. Using a Gaussian-type diffusion model, a high resolution concentration field was generated from 17 points representing the actual distribution of possible pollution sources. The starting grid consisted of 90 601 points. Then we reduced number of points by two orders of magnitude, forming the grid of 961 points. After that, the second reduction to 36 points was performed, still forming a regular grid. Finally, we had 16 points whose positions are in a qualitative agreement with the actual distribution of sampling stations in the area.

In the paper is presented an assessment of impact on the environment, of the assumed emissions of radio nuclides in the boundary layer of the atmosphere, from the ventilation of nuclear reactor in Vinca. This estimation was done taking into account characteristics of the reactor ventilation system, then based on the assumed emission of radioactivity (from the literature), local meteorology of Vinca for the period 2001-2005 and whole 2009 year, terrain topography around nuclear reactor and corresponding dose factors for inventory of radio nuclides. In the paper are also presented average annual activity concentration fields in the air and yearly activity due to dry and wet deposition, as well as annual dose received by the hypothetical resident in the period 2001-2005 and whole 2009 year. Radionuclide emissions from artificial sources should not contribute to the limit values of total dose above 1% of the dose received by an individual from natural background radiation (limit value 10-3Sv for a year). In this way, the limit value of the total dose for the individual is a 10-5 Sv, or 1e-5 Sv to the convention on the recording format of small numbers. Based on the results of mathematical modeling with parameters of the ventilation stack of nuclear reactor "RA", assumed emission of radio nuclides, soil characteristics, meteorological data collected with an automated meteorological station at 40m tall meteorological tower on the representative location at "RA", then on the recommended dose factors for the observed radionuclide’s and on the conservative approach that the reactor operates continuously 24 hours throughout the year, only in 2002 and 2005 in two isolated locations, maximum values for the total annual dose were slightly higher than the limit value, amounted to 1.1e-5 Sv. On the basis of the described approach and assuming that the range of appropriate meteorological data for the application of described mathematical model, of five consecutive years 2001-2005 a

U simulaciji prolaza čestica tehnikama Monte Karlo aktuelni geometrijski moduli upotrebljavaju površine prvog i drugog reda (FOTELP, PENELOPE, SHIELD, GEANT), a nekad i četvrtog reda(MCNP5), da opišu složene geometrijske forme.. Sve veća primena tehnika Monte Karlo u medicini oslanja se na vokselizovane geometrijske forme koje se dobijaju vokselizaciom fantoma ili iz CT podataka. Ogroman broj tela (voxela) u tom slučaju otežava primenu konstruktivne geometrije. Eefikasniji pristup tom problemu zasniva se na primeni virtuelnog voksela.Ovde se saopštavaju rezultati upotrebe virtuelnog voksela na anatomiju tela i organa upotrebom CT podataka., Geometry modules in particle transport simulation codes with Monte Carlo techniques use surfaces of first and second order, sometimes even a fourth order surfaces, to be able to describe complex geometrical shapes. Constructive quadric geometry dominates in all leading software packages. Increasing application of Monte Carlo techniques in medicine is associated with voxelized geometry forms. Huge number of bodies present in this case makes the use of constructive geometry more difficult. The paper describes an efficient approach to this problem by virtual voxel application, where optical distance to the boundary is obtained, and 3D voxel indices give information about the materials present in voxel.