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The purpose of this work is to assess accuracy and compare the performance of radionuclide calibrators (RNCs) used in nuclear medicine departments in Serbia. Testing of the RNCs included verification of measurement accuracy, as well as analysis of routinely used quality control protocols, by using the certified radioactivity standards (57Co, 137Cs). RNCs performances were assessed with 99mTc through comparison of reference value for radionuclide activity and RNC measurements. Results of the intercomparison revealed that RNCs, 15 in total, are accurate within 10% in vial geometry and within 15% in syringe geometry. Most of them showed similar performance. The results revealed that container geometry is an important influencing parameter in the accuracy of activity measurement. Obtained results indicate a need for regular calibration and implementation of Quality Control program in order to achieve and maintain the accuracy of activity measurements in nuclear medicine.

Doses from the exposure to outdoor radon are typically an order of magnitude smaller than those from indoor radon, causing a greater interest on investigation of the latter for radiation protection issues. As a consequence, assessment of radon priority areas (RPA) is mainly based on indoor radon measurements. Outdoor radon measurements might be needed to guarantee a complete estimation of radiological risk and may help to improve the estimation of RPA. Therefore, authors have analysed the available literature on outdoor radon to give an overview of outdoor radon surveys and potential correlation with indoor radon and estimation of RPA. The review has shown that outdoor radon surveys were performed at much smaller scale compared to indoor radon. Only a few outdoor radon maps were produced, with a much smaller density, covering a larger area, and therefore putting doubt on the representativeness of this data. Due to a large variety of techniques used for outdoor radon measurements and requirement to have detectors with a high sensitivity and resistance to harsh environmental conditions, a standardised measurement protocol should be derived. This is no simple endeavour since there are more applications in different scientific disciplines for outdoor radon measurements compared to indoor radon.

The European Council DIRECTIVE 2013/59/EURATOM laying down the basic safety standards for protection against the dangers arising from exposure to ionizing radiation is currently the main European regulation on ionizing radiation. The practical implementation of the European basic safety standards has become more complex due to the lack of consideration of the metrological implications and the adaptation to new technological developments, which lead to new standards, technological innovations, and improved capabilities. It was considered by EURAMET to be of a vital importance to have a metrology network that acts as a focal point between the metrology communities and the relevant radiation protection stakeholders, including regulators, standardization bodies, manufacturers, users of radiation sources and international organizations and radiation protection platforms. One of the most important tasks of this European Metrology Network (EMN) for Radiation Protection is to give a strong voice to the field of radiation protection metrology in Europe, so that it can provide responsible guidance and support to future technological developments. Additionally, metrological competence and capacity are essential to determine ambient or occupational exposures and urgent metrological needs exist in case of emergency situations. The EMN for Radiation Protection is in operation since 2021. The first Chair, Annette Röttger (PTB, Germany), Vice-Chair, Teemu Siiskonen (STUK, Finland) and Secretary Behnam Khanbabaee (PTB, Germany) have been elected. At the second meeting in 2022, first actions have been identified. In this contribution, the planned actions and next steps will be presented.

This paper presents a comparison performed between two calibration laboratories in several radiation qualities, using dosimeters of varying quality as transfer instruments. The goal of this work was to investigate the viability of using field-class dosimeters for official comparisons and to determine if the calibration factors for field-class dosimeters are comparable between calibration laboratories within the stated measurement uncertainties. The results of the comparison were acceptable for high-quality electronic personal dosimeters in all radiation qualities, and such dosimeters could be used as transfer instruments. On the other hand, comparison results for low-quality dosimeters were often not acceptable, either due to pronounced energy dependence, low stability, or both. Such instruments are unreliable even under well-defined laboratory conditions, and their use in routine measurements may cause doubt in official data or influence public opinion. This problem is often hidden because many dosimeters are calibrated or verified only in 137Cs beams, where the deviations are the smallest. The largest differences are found for low-energy X-ray radiation qualities, where many dosimeters have significant overresponse.

Radon flux measurements provide information about how much radon rises from the ground toward the atmosphere, thus, they could serve as good predictors of indoor radon concentrations. Although there are many different mapping methods with many different input data, radon flux data are generally missing and are not included for the delineation of radon priority areas (RPA). The aim of this literature review is to investigate to what extent radon flux was used, or could be used, for the delineation of RPAs. Numerous factors influencing radon flux were identified, but quantifying their contribution to radon flux measurement still remains a challenge. Different methods and measuring devices were used for the determination of radon flux, thus it is necessary to identify possible inconsistencies in order to harmonise different radon flux measurements. Due to the complexity of radon flux measurements, only two countries were identified to have performed national surveys on outdoor radon, which were of much smaller scale compared to those on indoor radon. A positive correlation between radon flux and radon quantities, such as radon in soil gas and indoor radon, indicates that radon flux could be used as an input parameter for the estimation of RPA. By reviewing radon flux models, it was concluded that up-to-date modelled radon flux maps have reached excellent spatial resolution and will be further improved, hence, they could serve as an input for the estimation and delineation of RPA.

Advancements in area monitoring caused by development of environmental monitoring networks which utilise active electronic dosimeters have led to widespread use of active area dosimeters. Currently, there are various sets of requirements for area dosimeters available in IEC standards. A clear distinction is not always made between requirements for area dosimeters used for workplace monitoring and that used for environmental monitoring. Performance testing methods related to the radiation characteristics were examined in a number of standards. Out of this, criteria in terms of relative response limits of variation have been derived for photon energy, angle of incidence and dose rate non-linearity for both dosimeter use cases. Testing of several active area dosimeters which are used for environmental monitoring has been performed in a wide range of photon energy, angle of incidence and dose rate. The collected requirements for environmental and workplace area dosimetry imply that some harmonization of IEC standards for area dosimeters is needed.

More than 23 million workers worldwide are occupationally exposed to ionizing radiation and all people in the world are exposed to environmental radiation. The mean exposure, that is the mean annual dose of per person, is dominated by medical applications and exposure to natural sources. Due to recent developments in healthcare, e.g. the increasing application of ionising radiation in medical imaging with relative high doses like CT, and modern high dose applications (for example CT angiography), the exposure due to medical application has risen. Additionally, the changes in living conditions increase the exposure to natural radioactivity also: More living time is spent in buildings or in an urban environment, which causes higher exposure to Naturally Occurring Radioactive Materials (NORM) in building materials and higher exposure to radon. The level of radon activity concentration in buildings is far higher than in the environment (outdoor). This effect is often amplified by modern energy-efficient buildings which reduce the air exchange and thus increase the radon indoor activity concentration. In summary both medical application of ionizing radiation and natural sources are responsible for the increase of the mean annual exposure of the population. The accurate measurement of radiation dose is key to ensuring safety but there are two challenges to be faced: First, new standards and reference fields are needed due to the rapid developments in medical imaging, radiotherapy and industrial applications. Second, direct communication channels are needed to ensure that information on best practice in measurements reaches effectively and quickly the people concerned. It is therefore necessary to allow for an international exchange of information on identified problems and solutions. Consequently, a European Metrology Network (EMN) for radiation protection under the roof of EURAMET is in the foundation phase. This network EMN for Radiation Protection is being prepared by

Passive solid state dosimeters, such as thermoluminescence dosimeters, provide integrated measurement of the total dose and are widely used in environmental monitoring programs. The objective of this paper is to provide a comprehensive review on the use of thermoluminescent dosimetry methods for monitoring radiation dose in the environment. The article presents the part of the research results of the project PREPAREDNESS (EMPIR 2016 call for Metrology for Environment joint research project) with a particular objective to harmonize procedures used by dosimetry services, relevant authorities and Institutes across the Europe. To achieve this, different monitoring routines that are based on passive environ mental dosimetry methods are investigated. Differences in performing specific steps such as preheating, reading, annealing, minimizing fading, and others, are analyzed. The investigation was performed by means of qualitative literature review that showed the lack of information about specific steps. The conclusion of this work is that thermoluminescent dosimetry measurement system has to be type-tested even though the testing procedure is complicated. In addition to this, control dosimeters should be introduced, International Organization for Standardization protocols should be followed during calibration, and finally, parameters influencing the measurement uncertainty have to be identified and well understood in order to pro duce ac cu rate dose measurement results.

In the aftermath of a nuclear or radiological accident, an extended mapping of reliable dose rate values is of key importance for any governmental decision and countermeasures. Presently, numerous dosimetry network stations, operated by the national governments of the member states in Europe, provide such dose rate data on an hourly basis. Nevertheless, there are large areas in Europe that are not covered at all by these early warning networks and other areas that show only a low density of governmental network stations. Hence, there may be a significant lack of information in case of a nuclear or radiological emergency. As a consequence of the Fukushima Daiichi nuclear power plant accidents in 2011, a number of non-governmental radiation monitoring networks (NRMN) appeared on the internet, providing dose rate data based on stationary as well as on mobile measurements of ionizing radiation by laypersons. Especially the mobile detectors are able to cover large areas in short time. Therefore, it is of considerable importance to investigate the feasibility of using dose rate data from non-governmental networks as a complementary input to the European Radiological Data Exchange Platform (EURDEP). Within the European Metrology Program for Innovation and Research (EMPIR), the project 16ENV04 “Preparedness” has studied the metrological relevance of such non-governmental dose rate data (also called crowd-sourced radiological monitoring) in the most comprehensive way so far. Sixteen different dose rate detector systems (in general 4 of each type, plus 2 types with 2 detectors, i.e. 68 detectors in total) used in NRMN have been investigated for the reliability of their data and the corresponding networks, and their data provision to the public were analyzed. The most relevant performance parameters of dosimetry systems (detector's inherent background, energy dependence and linearity of the response as well as the response to secondary cosmic radiation, the sensitivity to smal

Interventional procedures in radiology and cardiology are associated with high dose to the patient. Accurate dosimetry is essential and calibration of the equipment is a means to provide the necessary accuracy of dose assessment. The objective of this work is to investigate the performance of dosimeters used in interventional procedures in different standard and non-standard X-ray radiation qualities, and to investigate potential uncertainties related to dose measurements, thus improving accuracy of patient dosimetry in interventional procedures. Four new reference radiation qualities dedicated to interventional cardiology applications have been established, allowing calibration of dosimeters used in clinical conditions with appropriate traceability to primary standards. Testing of solid-state semiconductor detectors and thermoluminescent dosimeter properties, e.g. influence of photon energy, angle of incidence and dose rate, was performed in the standard and non-standard radiation qualities. Both dosimeter types showed good performance in the non-standard beams during all performance tests. Solid-state dosimeters displayed weak dependence on energy, angle of incidence and dose rate, in the range defined by the manufacturer and requirements of the international standard. Thermoluminescent dosimeters displayed excellent linearity and angular dependence. The influence of energy dependence on measurement uncertainty can be reduced if appropriate radiation quality is selected for calibration. © 2021 Elsevier Ltd

The European regulation on ionizing radiation is essentially laid down in the Council DIRECTIVE 2013/59/EURATOM. This Directive implements the basic safety standards for the protection of humans and the environment against the dangers arising from exposure to ionizing radiation. However, the practical implementation of the European basic safety standards has become more complex due to the lack of consideration of the metrological implications and the adaptation to new technological developments, which lead to new standards, technological innovations, and improved capabilities. It is therefore of vital importance to create a network that acts as a focal point between the metrology communities and the relevant radiation protection stakeholders, including regulators, standardization bodies, manufacturers, users of radiation sources and international organizations and platforms dealing with radiation protection such as HERCA, IAEA and EURADOS. The development of such a metrology network under the umbrella of EURAMET was planned by the consortium of the JNP EMPIR project 19NET03 supportBSS. The plan was successfully evaluated by EURAMET and the European Metrology Network (EMN) for Radiation Protection was approved by the EURAMET General Assembly in June 2021. The EMN for radiation protection will interact with innovative technological developments and has set itself the goal of being the central point of contact in order to cover the metrological needs in radiation protection and to find metrological solutions on a European level. The main challenges for this goal are in the first step the implementation of a long-term ongoing dialogue between the metrology communities and relevant stakeholder groups and, on the other hand, the development of a joint and sustainable European metrology infrastructure that underpins radiation protection regulation. The first step is visualized in this work.

Due to the need for harmonization of passive dosimetry and the requirements of the international standards in the area of environmental monitoring in radiation protection, multiple types of various passive dosimetry systems based on different ionizing radiation detection mechanisms were subjected to extensive performance testing. In the scope of the EMPIR project 16ENV04 Preparedness, the performance of 12 passive dosimetry systems was examined in radiation fields of different photon energies, angles of incidence and ambient dose equivalent rates in order to estimate their performance in the almost omni-directionally and energetically broad radiation field of the natural environment. The use of different detectors, holders, calibrations, measurement procedures and uncertainties, leads to differences in the measured data. Prior investigations and harmonization of passive dosimetry systems are necessary to achieve reliable and comparable dose measurements in Europe.

This paper presents experimental results of dynamic breakdown voltage and delay response as functions of gamma ray air kerma rate for xenon-filled tube at 2.7 mbar pressure. Gamma ray air kerma rate range was considered from 123 nGy h–1 up to 12.3 mGy h–1 in order to investigate the possibility of the application of this tube in gamma radiation dosimetry. It was shown that the variations of the above-mentioned parameters are considerable up to the dose rate of 1.23 μGy h–1, which points to the possibility for application in small dose rate gamma ray dosimetry. Physical processes that make dominant impact to dynamic breakdown voltage and delay response during xenon-filled tube irradiation are also discussed in the paper.

The second most important source of indoor radon, after soil beneath dwelling, is building material. With the increase in environmental awareness and new energy-saving policies, residents tend to replace the existing windows with tighter windows, which leads to a decrease in air exchange rate and consequently an increase in indoor radon concentration. In case of low exchange rates, dose caused by inhalation of radon and its progeny can exceed external dose originating from the radium content in the surrounding building material. In this paper, surface exhalation rates of radon ( 222 Rn) and thoron ( 220 Rn) from typical building materials used for construction and interior decoration of houses in Serbia were investigated. Surface exhalation rate measurements were performed using the closed-chamber method, while concentrations of radon and thoron in the chamber were continuously measured using an active device, RTM1688-2, produced by SARAD® GmbH. Finally, the impact of the replacement of windows on the indoor radon concentration was estimated.

Open-faced charcoal canisters have been used for radon measurements for over 40 years. This method is sensitive to temperature, changing radon concentrations, humidity and other parameters, but a comprehensive study dealing with the influence quantities and measurement uncertainty was not available in literature. In this paper, all the identified influence quantities are discussed in detail, uncertainty budget is developed, good practice and bad practice examples are introduced and new recommendations are proposed to optimize the method and reduce uncertainty.

In order to track “small dose effect” leading to stabilization of RADFETs with 1 μm thick oxide fabricated at Tyndall National Institute, Cork, Ireland irradiation was performed with gamma-rays in the radiation dose interval from 1 to 5 cGy, followed with room temperature annealing for the time of 28 days. Gate bias during irradiation was 0, 2.5 and 5 V. Threshold voltage shift ΔVT determined from transfer characteristics in saturation were followed during irradiation and annealing. It was shown that there is significant increase in ΔVT for 1 cGy radiation dose and those are 36.3, 43.3 mV and 45.7 mV for gate bias 0, 2.5 V and 5 V, respectively. For higher radiation doses ΔVT also increases, however, such increase is much lower. RADFETs fading at room temperature lead to permanent decrease in ΔVT and after 28 days the threshold voltage for devices is returned to virgin device value. Small dose effect is confirmed and radiation dose of at least 5 cGy is necessary for RADFET stabilization before their use in dosimetric application. After RADFETs stabilization they were irradiated in dose interval from 10 to 50 cGy with gate bias of 0, 2.5 and 5 V. It was shown that there is a linear dependence between ΔVT and absorbed radiation dose D, for gate bias during irradiation 0, 2.5 and 5 V. Defects responsible for threshold voltage shift, formed during irradiation as well as their neutralization/compensation during annealing, are also discussed. © 2019

The revised European Directive from 2013 regarding basic safety standard oblige EU Member States to establish a national action plan regarding the exposure to radon. At the same time, International Atomic Energy Agency started technical projects in order to assist countries to establish and implement national radon action. As a consequence, in recent years, in numerous countries national radon surveys were conducted and action plans established, which were not performed before. In this paper, a qualitative overview of radon surveys performed in Europe is given with a special attention to the qualitative and conceptual description of surveys, representativeness and QA/QC (quality assurance/quality control). © 2019

Tačna i sledljiva merenja operativnih veličina su neophodna za adekvatnu zaštitu od zračenja. Nacionalni metrološki instituti i Imenovani instituti su zaduženi za diseminaciju SI jedinice Sivert i za etaloniranje korisničke opreme. Ipak, u velikom broju Evropskih zemalja, mogušnosti etaloniranjaza operativne veličine su nedovoljno razvijene ili nepostoješe. Glavni cilj DOSEtrace projekta je unapređenje ovih mogućnosti, kao i smanjenje proširene merne nesigurnosti učesnika projekta ispod 5 % (k = 2). U okviru projekta še biti sprovedena Dodatna interkomparacija kalibracionih faktora za ambijentalni dozni ekvivalent. Ova interkomparacija še pomoši učesnicima projekta da validiraju merne mogušnosti razvijene pre i tokom projekta, a takođe će pomoći novim institutima da steknu međunarodno priznanje. U okviru intercomparacije, biše pokriveni kvaliteti zračenja radionuklida, kao i x-zračenja., Accurate and traceable measurements of operational quantities are required for adequate radiation protection. National Measurement Institutes (NMI) and Designated Institutes (DI) are responsible for disseminating the SI unit sievert and for calibrating user equipment. However, in many emerging European countries, calibration and measurement capabilities for operational quantities are limited or nonexistent. The main objective of DOSEtrace project is to improve these capabilities and for the participants to achieve the expanded measurement uncertainty of less than5% (k = 2). Within the project, a Supplementary comparison of calibration factors in terms of ambient dose equivalent will be conducted. This comparison will help to validate the capabilities that the partners developed during and before the project and will help emerging institutes gain international recognition. The comparison will cover both radionuclide and x-ray radiation qualities according to ISO 4037-1.

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.

Kontrola kvaliteta u radioterapiji je od velike vaţnosti za poboljšanje preciznosti i pouzdanosti radioterapijskih procedura. Minimizacija negativnih posledica po pacijente se postiţe smanjenjem verovatnoće pojavljivanja slučajnih i sistematskih grešaka identifikovanjem problema u postojećim standardnim procedurama u bolnicama. Značajna metoda kontrole kvaliteta rada radioterapijskih centara jeste program poštanske termoluminiscentne dozimetrije, zajednički organizovan od strane Međunarodne agencije za atomsku energiju i Svetske zdravstvene organizacije, a u kojem učestvuje oko 1700 bolnica širom sveta. Radioterapijski centri u Srbiji takođe učestvuju u ovom programu. Program poređenja apsorbovanih doza u vodi u radioterapijskim centrima u Srbiji je sproveden i tokom 2017, 2018. i 2019. godine. U tom periodu, broj obuhvaćenih centara je porastao sa šest na osam. Radiofotoluminiscentni dozimetri su ozračivani u visokoenergetskim poljima X-fotona generisanim pomoću linearnih akceleratora., Quality control in radiotherapy is of great importance in order to improve accuracy and reliability of radiotherapy procedures in hospitals. Minimization of the possible negative consequences of these procedures is achieved by reducing the probability of any random or systematic errors appearing, by determining the existing problems in the standard hospital procedures. One of the important methods for the radiotherapy facilities quality control is the postal thermoluminiscent dosimetry programme, co-organized by International Atomic Energy Agency and the World Health Organization, in which approximately 1700 hospitals throughout the world are participating. Radiotherapy centers in Serbia also participate in this programme, which has been executed during 2017, 2018 and 2019. During this period the number of participating radiotherapy centers in Serbia has increased from six to eight. Radiophotoluminiscent dosimeters have been irradiated in the high-energy X-ray fields generated by using linear accelerators.

Interventne procedure u radiologiji i kardiologiji povezani su sa visokim dozama za kožu pacijenta i potencijalnim radijacionim povredama kože. Različita metodologije i rešenja razvijene us za procenu maksimalne doze za kožu, čija se svojsvta, uključujuši i tačnost značajno razlikuju. U radu su prokazani ciljevi, metode i preminiran a rešenja projekta VERIDIC usmerenoj na validaciju zaličitih ofline i online softvera za procenu doze za kožu pacijenta u intervenatnoj kardiologiji., In interventional cardiology (IC), patients may be exposed to high doses to the skin resulting in tissue reactions (skin burns) following single or multiple procedures. To address this issue, online and offline software has been developed to estimate the maximum skin dose (MSD) to the patient from IC procedures. However, the capabilities and accuracy of such skin dose calculation (SDC) software to estimate MSD and 2D dose distributions markedly differ among vendors. Hence, this project focuses onthe harmonisation of RDSR (radiation dose structured report) and on the validation of SDC software products in IC, which will optimise radiation protection of patients. The outcome of the project will include the standards for digital dose reporting, development of protocols for acceptance testing and Quality Control (QC)of SDC software and setting of diagnostic reference levels per clinical complexity, assessing thefrequency of high-dose procedures as well as dose reduction strategies based on the multi-centric data collection. This paper focuses on the work performed to investigate performance of solid state dosimeters used in clinical environment.

Broj civilnih mreža koje pružaju kvazi-trenutne podatke o jačini doze je poslednjih godina u porastu. Ovi podaci su javno dostupni preko internet platfomi sa slobodnim pristupom. Istraživanja na temu civilnih mreža su retka, a merenja čiji su rezultati u njima predstavljeni su uglavnom izvršena široko dostupnim jednostavnim ručnim dozimetrima. Bez detaljnog testiranja ovih uređaja u metrološkim laboratorijama, postoji velika verovatnoša javljanja značajnih razlika između zvaničnih podataka i podataka iz civilnih mreža, što može imati značajne posledice. U okviru projekta 16ENV04 Preparedness je sprovedeno sistematskoispitivanje civilnih mreža. Tako je identifikovano 16 tipova uređaja koji se često koriste. Učesnici projekta su nabavili po 4 dozimetra od svakog tipa, čije je ispitivanje trenutno u toku. Procedura koriššena za ispitivanje je ukratko opisana u ovom radui prikazani su preliminarni rezultati za 2 tipa dozimetara., In recent years, the number of non-governmental networks providing quasi real time dose rates is growing. This data is available to the general public via open access based platforms on the internet. The research on the non-governmental networks is scarce and the measurements represented there are mostly carried out using broadly available commercial simple hand-held devices. Without proper testing of these devices in metrological laboratories, there is a significant possibility for discrepancies between the official and non-governmental data, which may have wider implications. Within project 16ENV04 Preparedness, a systematic study of non-governmental networks produced a list of 16 types of dosimeters that are commonly used. Four dosimeters of each type were sourced and commissioned by project partners and are currently undergoing the testing. Test procedures are shortly described in this paper and preliminary results for 2 types of dosimeters are presented.

Etaloniranje aktivnih ambijentalnih dozimetara izvodi se pri poznatim jačinama ambijentalnog doznog ekvivalenta pri čemu se vrši korekcija na vrednost prirodnog pozadinskog zračenja (fona). Izmerenu vrednost ambijentalnog doznog ekvivalenta zračenja u ţivotnoj sredini uvećava vrednost inherentnog fona detektora. Cilj ovog rada je ispitivanje aktivnih ambijentalnih dozimetara na niskom nivou fona unutar čelične zaštite brojača gama-aktivnosti celog tela i određivanje inherentne vrednosti pozadinskog zračenja za svaki dozimetar. Rezultati ispitivanja pokazuju da inherentno pokazivanje dozimetra moţe imati značajan uticaj na izmerene vrednosti ambijentalnog doznog ekvivalenta pozadinskog zračenja., Calibration of active ambient dosimeters is performed by using known values of ambient dose rate and with instrument background value subtraction. Measured value of ambient dose rate is increased by intrinsic background of the instrument. The goal of this paper is to assay response of active ambient dosimeters atlow background levels inside the shielding of a whole body counter installation and to assess the intrinsic background of the dosimeters. Test results show that intrinsic background of the instrument can substantially increase measured value of ambient dose rate in the environment.

Cilj ovog rada je da se ispita uniformnost i veličina referentnog polja generisanog pomoću generatora X-zračenja. U tu svrhu je koriššena jonizaciona komora male zapremine tako što su mapirane jačine doze. Na osnovu merenja, određen je korekcioni faktor za neuniformnost polja zračenja. Rezultati prikazani u ovom radu se odnose na polje kolimisano pomoću aperture prečnika 4,2 cm i generisano pomoću generatora X-zračenja konstantnog napona i struje. Ispitivanje je izvršeno u kvalitetu zračenja koji se koristi u dijagnostičkoj radiologiji, ali je ova procedura takođe primenjiva i na kvalitete koji se koriste za etaloniranje uređaja za zaštitu od zračenja definisane u novoj verziji ISO 4037 iz 2019. godine., The aim of this paper is to study the uniformity and the size of a reference radiation field produced by an x-ray generator. This work uses a technique to map dose distribution and measure dose rates with a small-volume spherical ionization chamber in order to determine the correction factor for non uniformity of the radiation field. Results shown in this paper are profile measurementsperformed in radiation beam collimated by a 4.2 cm diameter aperture, generated by calibration x-ray equipment of constant voltage and current. Thestudy was conducted in a diagnostic radiology radiation quality, but this procedure is also applicable to the new revised version of ISO 4037 standard from 2019 which specifies protection level reference radiation qualities.

16ENV04 Preparedness je projekat iz poziva EMPIR 2016 za zaštitu životne sredine. Glavni cilj projekta je poboljšanje pripravnosti za nuklearne i radiološke incidente i akcidente, koji bi mogli da se dogode u budušnosti. Pripravnost će biti poboljšana tako što će se izvršiti istraživanja u nekoliko pravaca: upotreba bespilotnih letelica za radiološka merenja, upotreba mobilnih sistema za uzorkovanje vazduha, istraživanje mogućnosti korišćenja radioloških podataka iz nevladinih mreža i korišćenje sistema pasivnih dozimetara za monitoring okoline. Još jedan od načina za poboljšanje pripravnosti je smanjenje mogušnosti bezrazložne panike koja bi mogla da bude izazvana diseminacijom merenja iz nevladinih mreža i drugih izvora, što bi moglo da izazove i smanjenje poverenja u zvanične podatke. U cilju realizacije projekta, od velikog značaja su diseminacija razultata i komunikacija sa svim zainteresovanim stranama., 16ENV04 Preparedness is a research project within the EMPIR 2016environment call. The main project goal is to increase the preparedness for nuclear and radiological incidents and accidents that might occur in the future. The preparedness will be increased by pursuing several directions of research: use of unmanned aerial vehicles for radiological measurements, use of transportable air-sampling systems, investigating the crowd sourced radiological data for possible official uses and investigating the use of passive dosimetry systems for ambient monitoring. Another aspect of preparedness is to try to reduce the possibility of unwarranted panic caused by the data disseminated by citizen networks and other sources and to increase confidence in official data. To realize the project goals, communication with stakeholders and dissemination of results are of greatest importance.

Након измерене високе концентрације радона у три просторије у једној кући почетком 2018. године, настављено је испитивање концентрације у свим годишњим добима, а број просторија је повећан на пет. Као што је очекивано, концентрација радона је у току летњих месеци била много мања него у зимском периоду, првенствено због сталног проветравања. У осталим годишњим добима уочена је велико повећање коцентрације радона са смањењем спољашње температуре. Такође је уочено смањење концентрације радона у свим просто-ријама наредне зиме, за приближно исти хладни период, када је уместо угља коришћен дрвени пелет., The high radon concentrations were measured in three rooms in one house at the beginning of 2018. After that, radon testing was continued during all seasons and the number of rooms was increased to five. As expected, the concentration of radon during the summer was much lower than in the winter period, primarily due to constant natural ventilation. In other seasons, a large increase in radon concentration with a decrease in the outside temperature was observed. There was also a decrease in radon concentrations in all rooms in the following winter, in approximately the same cold period, when wood pellets were used instead of coal.

Трогодишњи пројекат MetroRADON у оквиру програма EMPIR је фокусиран на следљивост мерења ниске концентрације радона и доприноси стварању координиране метролошке инфраструктуре за мониторинг радона у Европи као и хармонизацији методологија мерења. Циљеви пројекта су да се обезбеди метролошка следљивост калибрације инструмената на ниским концентрацијама са мерном несигурношћу мањом од 5%, да се испита утицај торона и његових потомака на мерење концентрације радона, да се упореде процедуре мерења концентрације радона и брзине ексхалације радона из земљишта у различитим државама у Евопи, да се развију методе идентификацје области са повећаном концентрацијом радона, да се све ове методе валидују и да се олакша коришћење технологије и мерне инфраструктуре коју је развио пројекат од стране крајњих корисника. У овом раду ће бити дат преглед циљева и досадасшњих резултата пројекта., MetroRADON, a three year project based in the EMPIR program, is focused on traceability of low activity radon measurement. It contributes to the creation of the coordinated metrological infrastructure for radon monitoring in Europe, as well as the harmonization of measurement strategy and methodology. The objectives of this project is to secure the metrological traceability of the instrument calibration for the measurement of low activity, with the measurement uncertainty that does not exceed 5%, to investigate the influence of thoron and its progenies on the radon concentration measurements, to compare procedures for measurement of indoor radon concentration and exhalation rate from the soil in different European countries, to develop methods for recognizing the radon priority areas and finally to validate these methods, but at the same time to enable the access of the final users to the measurement technology and infrastructure developed within this project. This paper presents the overview of these objectives and the results achieved in the present time.