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The European Association of National Metrology Institutes (EURAMET) within its research programme European Metrology Programme for Innovation and Research (EMPIR) funded project EMPIR 19NET03 supportBSS that contributes to the establishment of a European Metrology Network (EMN) for Radiation Protection (RP). The EMN-RP was established in September 2021 with the intent to work as a meeting point for the metrology community and all stakeholders in the field of ionising radiation regulation, thus providing quality assurance for measurements in each of the exposure situations contemplated in the European Legislation. Within project EMPIR 19NET03, work package 3 aims at the preparation of a Strategic Research Agenda (SRA) by identifying the metrology needs to support the European legislation and regulation in Radiation Protection and of two Roadmaps for metrology services, one under the European Council Directive 2013/59/EURATOM and the other under the EURATOM Treaty. Following a Gaps Workshop held in September 2020 and a second internal workshop that took place in April 2022, a questionnaire was prepared for distribution to the stakeholders, e.g. RP platforms and authorities, academia, industry, among other, together with an accompanying paper. In this paper, the authors present the state of the art of European legislation in RP, address the importance of metrology, the practices and activities that need metrology to meet the requirements set in the regulations, emphasise the need for quality assured measurements in all fields, highlight the stakeholders contributions in their specific area and show their vision of the EMN-RP.

Ancient DNA research in the past decade has revealed that European population structure changed dramatically in the prehistoric period (14,000–3000 years before present, YBP), reflecting the widespread introduction of Neolithic farmer and Bronze Age Steppe ancestries. However, little is known about how population structure changed from the historical period onward (3000 YBP - present). To address this, we collected whole genomes from 204 individuals from Europe and the Mediterranean, many of which are the first historical period genomes from their region (e.g. Armenia and France). We found that most regions show remarkable inter-individual heterogeneity. At least 7% of historical individuals carry ancestry uncommon in the region where they were sampled, some indicating cross-Mediterranean contacts. Despite this high level of mobility, overall population structure across western Eurasia is relatively stable through the historical period up to the present, mirroring geography. We show that, under standard population genetics models with local panmixia, the observed level of dispersal would lead to a collapse of population structure. Persistent population structure thus suggests a lower effective migration rate than indicated by the observed dispersal. We hypothesize that this phenomenon can be explained by extensive transient dispersal arising from drastically improved transportation networks and the Roman Empire’s mobilization of people for trade, labor, and military. This work highlights the utility of ancient DNA in elucidating finer scale human population dynamics in recent history.

This study reviews the performance analysis of a 137Cs irradiation system that has recently been installed in the laboratory of Uzbek National Institute of Metrology. The laboratory is responsible for calibrating calibration facilities and for calibrating most protection level radiation monitoring instruments used in medical, nuclear, industrial and academic settings in Uzbekistan. This system employs the most advanced radiation safety standards, along with 21st century source automation methods. In this work, we review the system’s performance according to ISO 4037 and present measurement uncertainty budget. Our analysis shows excellent results in terms of scattered radiation, beam uniformity and field size, change in source position, test for source impurities, chamber stability and source calibration, and all these parameters fully comply with the requirements of ISO 4037.

The effect of mammography measurement conditions was investigated to evaluate their impact on measurement uncertainties in clinical practice. The most prominent physical X-ray beam quantities i.e., air kerma, half-value layer, and X-ray tube voltage were examined by measuring the response of two ionization chambers and six X- ray multimeters (XMMs) of different models. Measurements were performed using several anode/filter combinations and both with and without the compression paddle in the X-ray beam. Maximum differences of higher than 6 % were found for all quantities when the dosimeter displayed value was compared with the reference value or the variation within the clinical anode/filter combinations Mo/Mo and Mo/Rh were considered. The study showed that the calibration procedure with the W/Al anode/filter combination was reliable only for ionization chambers, and the response of XMMs varies in such a way that the calibration coefficient cannot be predicted between various measurement conditions used in calibration and clinical practices. XMM calibrations are typically performed without a compression paddle in the beam, and the response of the XMM changes when radiation quality is slightly altered. If XMM specific data is not available, based on this study, an additional uncertainty of 2 % (k = 1) could be used as a typical estimate, at least for air kerma measurements. XMMs should be used for clinical measurements in mammography only with correct settings. If the correct settings are not available, the XMMs should not be used or used only with extreme caution.

The data contains measurement results for selected types of X-ray multimeters in mammography applications. In the Laboratory conditions absolute and relative response were determined for available software settings of the tested multimeters. In the clinical mammography units the multimeters' response was evaluated in different anode/filtration setups.

Introduction Calibration laboratories and industrial enterprises involved in radiation protection dosimetry face significant challenges following the recent update of the ISO 4037 in conjunction with the new radiation protection quantities introduced in ICRU Report 95, the gaps and contradictions in the standards that set photon dosimeter requirements, and the lack of standards for upcoming and new technologies. Methods The European Partnership Project 23NRM07 GuideRadPROS launched in June 2023 will address these issues over the next three years. The project objectives are: 1. to develop harmonized X-ray spectrometry in accordance with the ISO 4037 standard series, evaluate discrepancies between measured and calculated half value layer of X-ray spectra, and produce data to update requirements for reference fields. 2. to develop guidance and training material for the calibration of dosimeters. 3. to produce guidance on validated procedures for harmonized type testing based on IEC standards. 4. to investigate new and upcoming technologies and assess future standardization needs and to produce a guidance document for the implementation of the new operational quantities of ICRU Report 95 into standards and regulations. 5. to collaborate with ISO and IEC and users of their dosimetry standards to ensure that project outputs align with their needs. Results and Conclusions GuideRadPROS will improve the confidence in radiation protection dosimetry, both by promoting the implementation of the ISO 4037 standard series and by assessing the impact of the operational quantities of the ICRU Report 95 on daily measurements in radiation protection. Furthermore, the outcome of this project will lead to improved and comparable procedures in calibration and type testing within Europe

Accuracy of measurement in individual dosimetry monitoring service is achieved by performing calibration of dosemeters, ensuring that the measured values are traceable to the primary standard for the quantity of interest. Even though a dosemeter can exhibit remarkable performance in the reference calibration radiation field (e.g. 137Cs), its performance can greatly differ under certain conditions. Effects of different influence quantities need to be examined to ensure that the dosemeters are reliable for use in a specific ionizing radiation practice. The most significant radiation characteristic influence quantities are the radiation energy, angle of incidence and dose (rate). International standards issued by IEC and ISO define radiation conditions and procedures for dosemeter type testing under effects of different radiation, environmental and mechanical influence quantities. Dosemeter performance is expressed in terms of relative response and is evaluated by comparing with defined limits of variation, taking into account the measurement uncertainty, according to [IEC 62387:2020, IEC, 2020]. A passive dosimetry system based on LiF:Mg,Ti thermoluminescent dosemeters (TLD) was tested for the effects of photon energy and angle of incidence in two dosemeter orientations, horizontal (up/down) and vertical (left/right), for the measurement of personal dose equivalent (Hp(10) and Hp(0.07)). The dosemeters were read out on the Harshaw TLD™ Model 6600 Plus Automated Reader (Thermo Fisher Scientific, USA), calibrated in 137Cs reference field. Low-energy X-ray reference field N-40, established according to ISO 4037-1:2019 [ISO 4037, ISO, 2019] and ±45°, ±60° angles of incidence were used to examine the passive dosimetry system performance. Limits of variation from -29 % to +67 %, defined in [IEC 62387:2020, IEC, 2020] for energy and angular relative response, were used for performance evaluation. The overresponses for Hp(10) for 45° and 60° were (51 – 62) % and (76 – 88) %

Ionization chambers and solid state detectors incorporated into multimeters are often used for quality control in different modalities of medical imaging and diagnostic radiology. The equipment to be used in the routine QC procedures needs to be calibrated under well-known radiation conditions (known as radiation qualities) defined by the international standards. International standards IEC 61267:2005 [IEC 62167, IEC 2005] and IAEA TRS 457:2007 [IAEA TRS 457, IAEA 2007] cover general radiography and fluoroscopy radiation qualities (abbreviated as RQR and RQA series, in the voltage range from 40 kV to 150 kV), and computerized tomography radiation qualities (abbreviated as RQT series, in the voltage range from 100 kV to 150 kV), among other. In the field of mammography reference radiation fields are defined for molybdenum anode/filtration combination (Mo/Mo, abbreviated as RQR-M series, in the voltage range from 25 kV to 35 kV). Since Mo/Mo mammography units are widespread and available at hospitals they have been included in the standard [IEC 62167, IEC 2005]. Even so, Secondary Standard Dosimetry Laboratories (SSDLs) that are performing calibrations of QC dosimeters for end-users, rarely have availability of such anode/filtration combination under reference laboratory conditions. SSDLs most often employ X-ray generators with W/Al combinations. Additionally, nowadays many different combinations of anode/filtration are present in mammography units of different manufacturers that are commonly used in the hospitals. Multimeters are often sensitive to spectral changes caused by different anode/filter combination, so it is doubtful that the traceability established for one anode/filter combination can be used to measure doses for another combination. Measurements with different solid state detectors were performed under laboratory conditions with W/Al radiation qualities established in the SSDL. In the future, research will be expanded to clinical conditions in radiation

Quality Control (QC) measurements in diagnostic radiology are performed on a wide range of X-ray machines, used for different modalities such as radiography, fluoroscopy, mammography etc. Diagnostic radiology multimeters are in wide use in QC measurements [IAEA TRS 457, IAEA, 2007]. Many of these devices are based on several solid-state detectors positioned behind different filters, and values of different quantities can be calculated based on the signal from these detectors. Besides air kerma and X-ray tube high voltage, multimeters can often measure other special quantities, such as Half Value Layer (HVL), total filtration, irradiation time, product of current and time etc. Calibrations for these special quantities are very rarely available in Secondary Standards Dosimetry Laboratories (SSDL) or other calibration laboratories, so many end-users have problems to establish traceability. Research is currently being undertaken in Vinca Institute SSDL with the aim to establish traceability for HVL calibrations. HVL is a quantity that is commonly measured in SSDLs during internal QA/QC procedures, but there is no consensus on how to establish the traceability in SSDLs. Furthermore, measurement uncertainty for HVL is rarely estimated. In this research, HVL measurement procedure will be updated and detailed evaluation of measurement uncertainty will be undertaken. Sources of uncertainty that will be considered are: energy dependence of ionization chamber, thickness of aluminum filters, statistics of current measurements (reference chamber and monitor chamber), temperature, pressure etc. Traceable results of HVL measurements will further be used to calibrate and test multimeters in reference fields. In this paper, first results are presented.

Purpose: The European regulation for protection against exposure to ionizing radiation is essentially laid down in the Council Directive 2013/59/EURATOM. 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. To overcome such a difficulty, a European Metrology Network for Radiation Protection (EMN RP) was stablished in September 2021 to act 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. Materials and Methods: In the work package knowledge transfer, the supporting project 19NET03 supportBSS, together with its EMN RP partners, EURADOS and the German Federal Office for Radiation Protection (BfS), organizes an international training course on dosimetry and emergency preparedness in collaboration with the UK Health and Safety Agency (UK HSA) and the Greek Atomic Energy Commission (EEAE) as local host. The course will be held at EEAE in Athens, Greece, from 18 to 21 September 2023. Webpage: http://www.ptb.de/tceurados-wg2-2023 Results: The aim of this course is to provide the theoretical background of dealing with emergencies and to enhance it with practical measurement exercises. The course consists of three days of lectures and discussions combined with one day of practical exercises in small groups of five people. Lecturers from different European institutes will present various topics from different perspectives. Conclusions: This paper evaluates the course content and the feedback from the participants. This course can serve as a basis for further courses that can then be offered by appropriate platforms.

Well-type ionization chambers are routinely used for measurements in brachytherapy departments. Since there is no calibration service for brachytherapy ionization chambers available in Serbia, Secondary Standards Dosimetry Laboratory (SSDL) in Vinca Institute of Nuclear Sciences started establishing this service, using a reference well-type chamber Standard Imaging HDR-1000 plus with a PTW Unidos Webline electrometer. The outer wall of the chamber is made of 20 mm thick aluminum, which reduces the influence of the scattered radiation. For each source there is a unique source holder for placement in a reproducible geometry inside the well of the chamber. The ionization chamber stability has to be checked periodically to ensure reliable measurements. IAEA Technical Report Series (TRS) 1274 [IAEA TRS 1247, IAEA 2002] gives guidelines on standardized procedures at SSDLs and hospitals, including the procedure for stability checks of welltype chambers. According to this procedure, 137Cs or 60Co check sources are inserted in the chamber well, using spacers or holders to achieve reproducible geometry. Measurements during stability checks should remain within ±0.5%. In this research, a different procedure for stability checks was tested. A teletherapy 60Co irradiator was used for external irradiation of the well-type chamber. All measurements were corrected for air density (ambient temperature and pressure). Measurements were done in a minimum scatter environment, which was achieved by positioning the ionization chamber 1 m from the irradiator, with the field size of 20x20cm. Correction for 60Co half-life was applied to all measurements. First, the influence of the source holders was tested, and no significant differences were found (0.16% maximum difference when holder is placed in chamber, compared to no holder present). All the subsequent measurements were performed without source holders. During the second test, 4 stability checks were performed during a period of 4 days

Purpose: The recent update of the ISO 4037, in conjunction with the new radiation protection quantities introduced in ICRU Report 95, present significant challenges to calibration laboratories and industry. Furthermore, there is a need to address gaps and conflicts between standards that set requirements for photon dosimeters, and to incorporate upcoming and new technologies into standardization. Materials and Methods: The European Partnership Project 23NRM07 GuideRadPROS started in June 2023 and will address these issues in the next three years. The objectives are: • to develop harmonized X-ray spectrometry in accordance with the ISO 4037 standard series, evaluate discrepancies between measured and calculated half value layer of X-ray spectra, and produce data to update requirements for reference X-ray fields. • to develop guidance for the calibration of dosimeters. • to produce guidance on validated procedures for harmonized type testing based on IEC standards. • to assess future standardization needs and to produce a guidance document for the implementation of the new operational quantities of ICRU Report 95 into standards and regulations. • to collaborate with ISO and IEC and users of their dosimetry standards to ensure that project outputs align with their needs. Results: The outcome of this project will lead to improved and comparable procedures in calibration and type testing within Europe. Furthermore, the evaluation of the impact of the ICRU Report 95 quantities will allow for an informed realization of calibration fields. Conclusions: GuideRadPROS will improve the confidence in radiation protection dosimetry, both via the promotion of the implementation of the ISO 4037 standard series, and via the assessment of the impact of the ICRU Report 95 operational quantities on daily measurements in radiation protection.

Oko pola efektivne doze koju stanovništvo primi usled izlaganja jonizujućem zračenju potiče od radona i njegovih potomaka, te je problematika radona važna u oblasti zaštite od zračenja. Takođe, kao hemijski inertan gas, radon je našao primenu u izučavanju životne sredine kao traser za razne geološke i atmosferske procese. Jedna od važnih primena radona je u problematici praćenja gasova koji izazivaju efekat staklene bašte (greenhouse gases – GHG). Pokazano je da se poznavanjem fluksa radona iz zemlje i priraštaja koncentracije radona i koncentracije GHG u istom vremenskom intervalu tokom noći može odrediti fluks GHG. U ovom radu će biti prikazani odabrani rezultati nedavno završenog traceRadon projekta čiji je cilj bio razvijanje metrološki sledivih metoda merenja niskih koncentracija radona u atmosferi u granicama od 1 Bq m-3 do 100 Bq m-3, kao i unapređenje tehnika merenja i samo merenje radonskog fluksa, što će doprineti ispitivanju klimatskih promena kroz obezbeđivanje pouzdane procene fluksa GHG. Takođe, u sklopu projekta, vršila se procena do koje mere se radon u spoljašnjoj sredini i radonski fluks mogu koristiti za procenu radonskih prioritetnih oblasti., Since more than a half of the effective doses from all ionising radiation come from the exposure to radon and its progeny, radon is important in the field of radiation protection. Being a noble gas and therefore chemically inert, radon is also used as a tracer for different geological and atmospheric processes. Radon is of interest to climate scientists for monitoring greenhouse gasses (GHG). It is known that by knowing radon flux and variation of radon and GHG concentration at the same period of time during the night, it is possible to estimate emission of GHG. In this paper, the most important results of recently finished EMPIR project 19ENV01 traceRadon “Radon metrology for use in climate change observation and radiation protection at the environmental level” are presented. Project aimed to develop the capability to measure SI traceable radon activity in the range of 1 Bq m-3 to 100 Bq m-3, suitable for outdoor radon measurements, to develop the capability for traceable radon flux measurements in the field which is important for GHG emission estimates and validation of contemporary radon flux models. Within the project it was investigated to what extent radon flux and outdoor radon data could be used for estimation of radon priority areas.

The paper analyses the possibility of commercial neon indicator lamp at low pressure application as a gamma radiation detector. The diode is most often used as an indicator in electrical switchers. The analysis was performed on the basis of experimental electrical breakdown time delay data as a function of relaxation time, applied voltage and gamma ray air kerma rate. It has been shown that the indicator can be used as a detector for relaxation time greater than 70 ms. During this time period, a complete recombination/de-excitation of the particles formed during previous breakdown and subsequent self-sustaining discharge, which can further initiate next breakdown, takes place. It was also shown that gamma radiation leads to a significant reduction in electrical breakdown time delay for applied voltages close to indicator breakdown voltage. Based on the behavior of the dependence of the mean value of the electrical breakdown time delay on the gamma ray air kerma rate, it was shown that the indicator can be used very efficiently as a detector up to air kerma rate of 2.3 · 10-5 Gy/h, when the electrical breakdown time delay is measured for applied voltage 10% higher than the breakdown voltage. © 2023 The Author(s).

A need for detailed testing of individual monitoring systems used in accredited service at the Vinca Institute of Nuclear Sciences was recognized following changes in individual, workplace, and environmental monitoring passive dosimetry systems acceptability criteria stated in IEC 62387:2020 and changes related to reference fields used in radiation protection defined in ISO 4037:2019. Reliability and accuracy of dosimetry data acquired by passive dosimetry systems used for individual monitoring is assured by carrying out type tests. In this manner, the effects of different radiation influence quantities are examined. Passive dosimetry systems comprised of an LiF:Mg,Ti (TLD-100) detector card placed in two different holder models (8814 and 8850) and the Harshaw TLD Model 6600 Plus Automated Reader were tested. Type tests were done in an extended range of photon energies from 40 keV up to 1.25 MeV, angle of incidence values of ±45° and ± 60° for both vertical and horizontal dosimeter orientation, and in the dose range from 0.05 mSv to 1 Sv. Both dosimetry system configurations perform in line with IEC 62387:2020 within mandatory range for tested influence quantities. Dosimeters that use the 8850 holder type showed less pronounced energy and angular dependence of the response in the low-energy range.