Following the publication of the joint The International Commissions on Radiation Units and Measurements (ICRU) and on Radiological Protection (ICRP) report on new operational quantities for radiation protection, the European Dosimetry Group (EURADOS) have carried out an initial evaluation. The EURADOS report analyses the impact that the new quantities will have on: radiation protection practice; calibration and reference fields; European and national regulation; international standards and, especially, dosemeter and instrument design. The task group included experienced scientists drawn from across the various EURADOS working groups.

EURADOS (European Radiation Dosimetry Group) Working Group 12 (WG12) SG1 activities are aimed at occupational radiation protection and individual monitoring in X-ray and nuclear medicine practices. In recent years, many studies have been carried out in these fields, especially for interventional radiology and cardiology workplaces (IC/IR). The complexity of the exposure conditions of the medical staff during interventional practices makes the radiation protection and monitoring of the exposed workers a challenging task. The scope of the present work is to review some of the main results obtained within WG12 activities about scattered field characterization and personal dosimetry that could be very useful in increasing the quality of radiation protection of the personnel, safety, and awareness of radiation risk. Two papers on Monte Carlo modelling of interventional theater and three papers on active personal dosimeters (APDs) for personnel monitoring were considered in the review. More specifically, Monte Carlo simulation was used as the main tool to characterize the levels of exposure of the medical staff, allowing to determine how beam energy and direction can have an impact on the doses received by the operators. Indeed, the simulations provided information about the exposure of the operator’s head, and the study concluded with the determination of an eye-lens protection factor when protection goggles and a ceiling shielding are used. Moreover, the review included the results of studies on active personal dosimeters, their use in IC/IR workplaces, and how they respond to calibration fields, with X-ray standard and pulsed beams. It was shown that APDs are insensitive to backscatter radiation, but some of them could not respond correctly to the very intense pulsed fields (as those next to the patient in interventional practices). The measurements during interventional procedures showed the potential capability of the employment of APDs in hospitals.

Occupational radiation doses from interventional procedures have the potential to be relatively high. The requirement to optimise these doses encourages the use of electronic or active personal dosimeters (APDs) which are now increasingly used in hospitals. They are typically used in tandem with a routine passive dosimetry monitoring programme, with APDs used for real-time readings, for training purposes and when new imaging technology is introduced. However, there are limitations when using APDs. A survey in hospitals to identify issues related to the use of APDs was recently completed, along with an extensive series of APD tests by the EURADOS Working Group 12 on Dosimetry for Medical Imaging. The aim of this review paper is to summarise the state of the art regarding the use of APDs. We also used the results of our survey and our tests to develop a set of recommendations for the use of APDs in the clinical interventional radiology/cardiology settings, and draw attention to some of the current challenges.

Since 2012, the European Radiation Dosimetry Group (EURADOS) has developed its Strategic Research Agenda (SRA), which contributes to the identification of future research needs in radiation dosimetry in Europe. Continued scientific developments in this field necessitate regular updates and, consequently, this paper summarises the latest revision of the SRA, with input regarding the state of the art and vision for the future contributed by EURADOS Working Groups and through a stakeholder workshop. Five visions define key issues in dosimetry research that are considered important over at least the next decade. They include scientific objectives and developments in (i) updated fundamental dose concepts and quantities, (ii) improved radiation risk estimates deduced from epidemiological cohorts, (iii) efficient dose assessment for radiological emergencies, (iv) integrated personalised dosimetry in medical applications and (v) improved radiation protection of workers and the public. This SRA will be used as a guideline for future activities of EURADOS Working Groups but can also be used as guidance for research in radiation dosimetry by the wider community. It will also be used as input for a general European research roadmap for radiation protection, following similar previous contributions to the European Joint Programme for the Integration of Radiation Protection Research, under the Horizon 2020 programme (CONCERT). The full version of the SRA is available as a EURADOS report (www.eurados.org).

The European Radiation Dosimetry Group (EURADOS) is a network of organizations and scientists promoting research and development in the dosimetry of ionizing radiation, contributing to harmonization in dosimetry practice across Europe, and offering education and training in areas relevant for dosimetry. As a registered non-profit association under German law, EURADOS is currently running eight active working groups (WGs): WG2 on "Harmonization of Individual Monitoring", WG3 on "Environmental Dosimetry", WG6 on "Computational Dosimetry", WG7 on "Internal Dosimetry", WG9 on "Dosimetry in Radiotherapy", WG10 on "Retrospective Dosimetry", WG11 on "Dosimetry in High-Energy Radiation Fields", and WG12 on "Dosimetry in Medical Imaging". This paper presents recent scientific results obtained within these working groups, and additionally highlights the role of EURADOS as an organization which contributes to the development of a systematic strategy of radiation protection research in Europe.

In order to address the recent concerns over a possible increasing in brain tumour mortality among interventional radiologists and cardiologist, this work evaluated the exposure conditions of the operator's brain during interventional procedures using Monte Carlo simulations with anthropomorphic phantoms. The absorbed doses in several predefined segments of the operator's brain were estimated in a typical interventional radiology irradiation scenario. The doses were normalized to the KAP values simulated for ten X-ray beam qualities and four projections (PA, RAO 25°, LAO 25° and CRA 25°). For the interventional radiology scenario, because of the position of the operator, no difference was found in the exposure between the left and right regions of the brain for the first operator. However, for the second operator standing at a farer distance from the tube, the exposure of the left part of the brain is up to two times higher than that of the right part. The results are in agreement with dose measurements reported in the literature. The conversion factors, obtained as the absorbed dose per KAP, can be used to obtain a first estimate of the exposure of the brain of the operators during interventional procedures.

This work presents a comparison of simulated early radiation-induced DNA damage represented by yields of double-strand breaks (DSB) in three different human cell nuclei geometries representing fibroblasts, lymphocytes and endothelial cells for protons and alpha particles of different energies and for different irradiation configurations. Each cell nucleus model includes a multi-scale description of the DNA target from the molecular level to the whole human genome representation (6 Gbp) in the G0/G1 phase of the cell cycle and was generated with the DnaFabric software. The three nuclei differ in shape, volume, and therefore DNA density. A calculation chain based on Geant4-DNA that takes into account the physical, physico-chemical and chemical stages was used to simulate the irradiation of the different cell nuclei. Results show an increase of DSB/primary/μm with an increase of DNA density and an increase of DSB/Gy/Gbp with an increase of the cell nucleus volume which indicates that the cell nucleus shape and size have an impact on early DNA damage, which may play a role in latter effects.

This paper provides a summary of the Education and Training (E&T) activities that have been developed and organised by the European Radiation Dosimetry Group (EURADOS) in recent years and in the case of Training Courses over the last decade. These E&T actions include short duration Training Courses on well-established topics organised within the activity of EURADOS Working Groups (WGs), or one-day events integrated in the EURADOS Annual Meeting (workshops, winter schools, the intercomparison participants’ sessions and the learning network, among others). Moreover, EURADOS has recently established a Young Scientist Grant and a Young Scientist Award. The Grant supports young scientists by encouraging them to perform research projects at other laboratories of the EURADOS network. The Award is given in recognition of excellent work developed within the WGs’ work programme. Additionally, EURADOS supports the dissemination of knowledge in radiation dosimetry by promoting and endorsing conferences such as the individual monitoring (IM) series, the neutron and ion dosimetry symposia (NEUDOS) and contributions to E&T sessions at specific events.

Medical staff in interventional procedures are among the professionals with the highest occupational doses. Active personal dosemeters (APDs) can help in optimizing the exposure during interventional procedures. However, there can be problems when using APDs during interventional procedures, due to the specific energy and angular distribution of the radiation field and because of the pulsed nature of the radiation. Many parameters like the type of interventional procedure, personal habits and working techniques, protection tools used and X-ray field characteristics influence the occupational exposure and the scattered radiation around the patient. In this paper, we compare the results from three types of APDs with a passive personal dosimetry system while being used in real clinical environment by the interventional staff. The results show that there is a large spread in the ratios of the passive and active devices.

Radiation overexposure accidents are rare but can have severe health consequences. Evaluating the dose received by the patient is a crucial step in the medical management. For that purpose, for more than 15 years, IRSN has been developing an in-house tool named SESAME for the numerical reconstruction of radiological accidents due to external sources. Recently, two new functionalities were implemented in SESAME to allow accurate reconstructions of interventional radiology (IR) overexposures. The experimental validation of SESAME for the reconstruction of overexposures in IR is presented. First, an anthropomorphic dummy equipped with dosemeters was irradiated following conditions similar to a fluoroscopically guided interventional procedure. Then the procedure was simulated using SESAME. Finally measured doses were compared to calculated doses. Even with a limited amount of data available, SESAME can provide valuable dose information for the medical team in charge of the patient, such as skin dose mapping and dose distribution in depth.

PURPOSE:This study aims at characterising the properties of TruView™ and ClearView™ two new gel dosimeters (Modus Medical Devices Inc.) and at studying the feasibility of relative dosimetry using these dosimeters and the Vista™ Optical CT scanner to accurately evaluate dose. METHODS:In this work, we investigated key dosimetric aspects (dose response, energy and dose rate dependence) and stability of these radiochromic gels initiated in preliminary works (Huet et al., 2017; Colnot et al., 2017) using spectrophotometric measurements. Moreover, by mean of optical CT scanning (Vista™), their performances to measure relative depth dose (PDD) and cross profiles were analysed. RESULTS:TruView™ and ClearView™ present a linear dose response up to 20 Gy and up to 80 Gy respectively, independent of both photon beam energy (4-18 MV) and dose rate (up to 9.9 Gy/min) (Huet et al., 2017; Colnot et al., 2017). ClearView™ response proves to be stable for a week post-irradiation and uniform within the batch whereas TruView™ presents an unstable but uniform response. Optical CT scanning generates errors due to stray light that need to be corrected in order to use these gels; ClearView™ scanning particularly requires important precautions. After corrections, those gels used in combination with the Vista™ scanner show promising spatial and dosimetric precision (dose difference <5%). Finally, TruView™ is reusable and presents excellent reproducible response (maximum 3% difference) and the ClearView™ dosimeter presents good spatial stability (0.5% difference after 6 days). CONCLUSION:This study provides important knowledge about two gel dosimeters presenting interesting dosimetric properties. A study is ongoing to benchmark those promising candidates for clinical dose verification.

In the context of a new annual eye lens dose limit for occupational exposure equal to 20 mSv, European Radiation Dosimetry Group (EURADOS) organized an intercomparison dedicated to eye lens dosemeters, including photon and beta radiations. The objective was to complete the first intercomparison recently organized by EURADOS for photons and to update the overview of eye lens dosemeters available in Europe. The dosemeters provided by the 22 participants coming from 12 countries were all composed of thermoluminescent detectors. The dosemeters were irradiated with photon and beta fields defined in relevant standards. The results, provided by participants in terms of Hp(3), were compared to the reference delivered doses. Results are globally satisfactory for photons since 90% of the data are in accordance to the ISO 14146 standard requirements. The respective values for betas stress the fact that dosemeters designed for Hp(0.07) are not suitable to monitor the eye lens dose in case of betas.

In fluoroscopy guided interventional procedures, workers use protective garments and often two personal dosemeters, the readings of which are used for the estimation of the effective dose; whereas the dosemeter above the protection can be used for the estimation of the equivalent dose of the lens of the eye. When a protective apron is worn the scattered field that reaches the dosemeter is different from the case where no protection is used; this study analyses the changes in the response of seven passive and eight active personal dosemeters (APDs) when they are placed above a lead or lead equivalent garment for S-Cs and x-ray diagnostic qualities. Monte Carlo simulations are used to support the experimental results. It is found that for passive dosemeters, the influence on the dosemeter's response to the lead or lead equivalent was within the range 15%-38% for the x-ray qualities. This effect is smaller, of the order of 10%, when lead-free garments are used, and much smaller, within 1%-10%, for most of the APDs used in the study. From these results it is concluded that when comparing passive and active dosemeter measurements worn above the protection, a difference of 20%-40% is expected. The effect is small when deriving the effective dose from double dosimetry algorithms, but it can be of major importance when eye lens monitoring is based on the use of the dosemeter worn above the protection.

EURADOS (European Radiation Dosimetry Group) Working Group 12 (dosimetry in medical imaging) established a subtask devoted to the dosimetry of the medical staff employed in interventional radiology practices. As it is widely known, such practices are characterized by high doses, with respect the other medical procedures, both for the patient and the radiologist. For interventional cardiology there are several publications concerning medical staff dosimetry, on the contrary, for interventional radiology, data are more limited. For that reason WG-12 decided to study the irradiation scenario, employing simplified anthropomorphic models (MIRD type) with Monte Carlo simulations, reconstructing some specific interventional radiology practices (PTC and TIPS). In these procedures, where the X-ray C-arm is mainly fixed in PA projection and the beam directed to the patient abdomen, the radiologist is next to the patient right side, in correspondence to the liver region. The usage of the ceiling shielding is not very frequent, due to the difficulties in positioning it between the radiation source (the X-ray and the patient as the scattering source) and the operator. The aim of the simulations program is: to evaluate the dose received by the radiologist, in a region simulating the presence of the dosemeter fixed on the lead apron at the breast level ; to estimate the corresponding effective dose ; to make a sensitivity analysis on different parameters affecting the calculated results (as the reciprocal position between the two operators, the beam quality and the X-ray field dimension). Indeed a particular attention is devoted to the eye lens dosimetry, that has become a “critical issue” for personnel dosimetry, after ICRP has reconsidered the radiation sensitivity of the lens of the eye. In the present work the general scheme, the assumptions and the followed methodology are presented with some very preliminary results of the simulations and the measurements.

Due to recent technological advances, new optical stimulation sources with higher energies became commercially available. In the present work, laser diodes emitting in the violet (similar to 405 nm) were used to investigate dosimetric characteristics of the violet stimulated luminescence (VSL) signal from electronic components (resistors and inductors) extracted from mobile phones. All component types exhibit higher sensitivity using violet stimulation than using blue one. The sensitization was negligible after 10 cycles of irradiation and measurement. The dose response was linear from 0.6 Gy to 30 Gy. Additionally, signal fading of one type of inductors was studied. Results were similar for blue stimulated luminescence (BSL) and VSL signals. Fading measurements performed at 40 degrees C after a preheat (125 degrees C hold for 10 s) or at 125 degrees C indicated low fading rates (similar to 95% of signal remaining 1 h after irradiation). These preliminary results appear to be promising for retrospective dosimetry. (C) 2017 Elsevier Ltd. All rights reserved.

TruView™ is a new water-equivalent reusable Fricke gel dosimeter based on MethylThymolBlue reactive dye. Details of the characterisation of the TruView™ MTB gel dosimeter by spectrophotometric measurements and of its reading with the Optical-CT Scanner Vista™ are described. In this study, the different parameters influencing TruView™ dose response have been studied and its performances have been compared to chamber and diodes measurements. This gel presents a linear response with dose up to 20 Gy, independent in the investigated range of photon beam energy and dose rate and also a good intra-batch uniformity. Ions diffusion into the matrix homogenizes the gel after a week, losing dosimetric information but allowing a new irradiation to be performed. However, auto-oxidation happens before and after irradiation, degrading the dosimeter response and stability. Storage and reading conditions affect the response as well.

ClearView™ is a single-use radiochromic 3D dosimeter designed by Modus Medical Devices Inc. Some of the dosimetric characteristics of this gel, such as response as a function of dose and as a function of energy were investigated. Moreover, a 400 mL jar was irradiated with a 1x1 cm2 field and PDD and cross-profiles were compared to those obtained with active detectors. Small volumes of gels were found to exhibit a linear response to dose in the dose range 10-80 Gy. Promising PDD and cross profiles were obtained. Artefacts obtained in high resolution for the PDD are suspected to come from small inhomogeneities in the gel.

After the Fukushima accident, initiatives emerged from the public to carry out themselves measurements of the radioactivity in the environment with various devices, among which smartphones, and to share data and experiences through collaborative tools and social networks. Such measurements have two major interests, on the one hand, to enable each individual of the public to assess his own risk regarding the radioactivity and, on the other hand, to provide “real time” data from the field at various locations, especially in the early phase of an emergency situation, which could be very useful for the emergency management.The objective of the OPENRADIATION project is to offer to the public the opportunity to be an actor for measurements of the radioactivity in the environment using connected dosimetric applications on smartphones. The challenge is to operate such a system on a sustainable basis in peaceful time and be useful in case of emergency. In “peaceful situation”, this project is based on a collaborative approach with the aim to get complementary data to the existing ones, to consolidate the radiation background, to generate alerts in case of problem and to provide education & training and enhanced pedagogical approaches for a clear understanding of measures for the public. In case of emergency situation, data will be available “spontaneously” from the field in “real time” providing an opportunity for the emergency management and the communication with the public. …The practical objective is i) to develop a website centralising data from various systems/dosimeters, providing dose maps with raw and filtered data and creating dedicated areas for specific initiatives and exchanges of data and ii) to develop a data acquisition protocol and a dosimetric application using a connected dosimeter with a bluetooth connection.This project is conducted within a partnership between organisms’ representative of the scientific community and associations to create links with the public.

In order to improve the understanding of the mechanisms involved in the generation of early DNA damage, a new calculation chain based on the Geant4-DNA toolkit was developed. This work presents for the first time the simulation of the physical, physicochemical and chemical stages of early radiation damage at the scale of an entire human genome (fibroblast, male) and using Geant4-DNA models. The DnaFabric software was extended to generate and export this nucleus model to a text file with a specific format that can be read by Geant4 user applications. This calculation chain was used to simulate the irradiation of the nucleus by primary protons of different energies (0,5; 0,7; 0,8; 1; 1,5; 2; 3; 4; 5; 10; 20 MeV) and the results, in terms of DNA double strand breaks, agree with experimental data found in the literature (pulsed field electrophoresis technique). These results show that the simulation is consistent and that its parameters are well balanced. Among the different parameters that can be adjusted, our results demonstrate that the criterion used to select direct strand break appears to have a very significant role on the final number of simulated double strand breaks.