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Monte Carlo calculations were used to investigate the efficiency of radiation protection equipment in reducing eye and whole body doses during fluoroscopically guided interventional procedures. Eye lens doses were determined considering different models of eyewear with various shapes, sizes and lead thickness. The origin of scattered radiation reaching the eyes was also assessed to explain the variation in the protection efficiency of the different eyewear models with exposure conditions. The work also investigates the variation of eye and whole body doses with ceiling-suspended shields of various shapes and positioning. For all simulations, a broad spectrum of configurations typical for most interventional procedures was considered. Calculations showed that ‘wrap around’ glasses are the most efficient eyewear models reducing, on average, the dose by 74% and 21% for the left and right eyes respectively. The air gap between the glasses and the eyes was found to be the primary source of scattered radiation reaching the eyes. The ceiling-suspended screens were more efficient when positioned close to the patient’s skin and to the x-ray field. With the use of such shields, the H-p(10) values recorded at the collar, chest and waist level and the H-p(3) values for both eyes were reduced on average by 47%, 37%, 20% and 56% respectively. Finally, simulations proved that beam quality and lead thickness have little influence on eye dose while beam projection, the position and head orientation of the operator as well as the distance between the image detector and the patient are key parameters affecting eye and whole body doses.

The medical staff performing interventional cardiology and radiology (IC/IR) procedures stand close to the patient and thus close to the primary radiation beam. Although they wear a lead apron and thyroid collar, their hands, legs and eyes are not protected. Therefore, these parts could receive significantly high doses. Moreover, thedose ranges for the same kind of procedures vary a lot, as many factors affect extremity and eye lens doses. Additionally, there is evidence that eye lens doses can be high in IR/IC, and cases of cataract have been reported in recent years. A lack of an appropriate eye lens dosemeter as well as an appropriate calibration procedure has been identified. Medical staff in IR/IC could benefit from the use of active personal dosemeters (APDs) as optimisation tool. However, a lack of appropriate APDs is identified for typical fields in IR and IC. Very few devices can detect low energy fields, and none of them are really designed for working in pulsed radiation fields. In the field of nuclear medicine (NM) the extremity doses to the technologists are also known to be very high. One can highlight the difficulties in estimating the dose distribution across the hands, and the need for greater knowledge of doses received during the main tasks of a nuclear medicine department, especially using unsealed sources. The ORAMED project, (www.oramed-fp7.eu) was set up to optimize the working procedures in these medical fields with respect to radiation protection. ORAMED wasstructured in 5 work packages: - Extremity and eye lens dosimetry in IR and IC - Development of practical eye lens dosimetry - Optimization of the use of APDs in IR and IC - Extremity dosimetry in NM - Training and dissemination A coordinated measurement program in European hospitals was organised both in IR/IC and NM departments. Moreover, simulations of the most representative workplaces/procedures were performed to determine the main parameters that influence the extremity and eye lens doses. Some dedicated studies on improving the eye lens dosimetry and active personal dosimetry were conducted. Based on the measurement and simulation results, a series of practical guidelines and training packages were developed. The influence of the different radiation protection measures (like shields)in IR/IChave been quantified, and clear monitoring requirements have been formulated for a series of medical procedures. A formalism for the use of the operational quantity for eye lens dose measurements have been worked out (calibration phantom, conversion coefficients, type test procedures, ...). A dedicated eye lens dosemeter has been developed that can be used in routine monitoring. The different existing APDs have been tested in fields that are representative for hospital fields (like pulsed fields), and a series of guidelines for the use of these APDs in hospitals have been made. Also, an improved APD device specifically for IR/IC fields has been developed.The extensive measurement and simulation campaign for extremity doses in NM lead to a systematic evaluation of the different radiation protection measures. These are condensed in a series of practical guidelines to be used. The dose distribution across the hands of the technologists was characterised, and recommendations for routine monitoring have been formulated. The outcome of the ORAMED project will improve the radiation protection standards for medical staff. The systematic measurements and simulations are the new standards that will be used for many years to come. The practical guidelines that have been developed can be used in the hospitals by the medical staff. In particular, the developments on the eye-lens dosimetry and the active personal dosemeters will result in an improvement of the practical measurement capabilities in the field.

Objective: to determine the potential of leaded radiation attenuation gloves to decrease the X-ray exposure of operators' hands, in interventional radiology and in surgical units. Material and method: we used: radiation attenuation gloves bought by our hospital, TLD thermoluminescent dosimeters, an anthropomorphic phantom of calibration in bone densitometry, an anthropomorphic hand. The measurements were realized on 2 installations: one with sensor plans, and the other one with a brightness amplifier. We compared doses received by dosimeters without and in a glove, in the direct field (10 series of measurements, 2 with the brightness amplifier) and in the diffuse field (3 series on sensor plans), in fluoroscopy and graphy. Results: in the diffuse field, dosimeters in the glove measured a decrease in dose, varying from 1 to 3. In the direct field, 7 measurements out of 10 showed an increase in dose in the glove (13 to 42%). 3/10 measurements showed an almost stable dose. Conclusion: our measurements show the efficiency ofleaded radiation attenuation gloves in the diffuse field. In the direct field, the radiation attenuation gloves increase the hand dose, because of the automatic tuning of the parameters. © EDP Sciences, 2011.; Objectif : déterminer l’intérêt des gants radio-atténuateurs plombés pour diminuer l’exposition des mains des opérateurs, en radiologie interventionnelle et au bloc opératoire. Matériel et méthode : on a utilisé des gants radio-atténuateurs plombés du marché, des dosimètres TLD thermoluminescents, un fantôme anthropomorphe de calibration en ostéodensitométrie, une main anthropomorphe. Les mesures étaient réalisées sur 2 installations : l’une avec capteurs plans, l’autre avec amplificateur de brillance. On a comparé les doses reçues par dosimètres sans et dans un gant, dans le champ direct (10 séries de mesures dont 2 avec amplificateur de brillance) et dans le diffusé (3 séries sur capteurs plans), en scopie et graphie. Résultats : dans le diffusé, les dosimètres dans le gant mesuraient une diminution de dose, variant de 1 à 3. Dans le champ direct, 7 mesures sur 10 montraient une augmentation de dose dans le gant (13 à 42 %). 3/10 mesures montraient une quasi stabilité de dose avec le gant (–3,3 % à +2 %). Conclusion : nos mesures objectivent une efficacité des gants radio-atténuateurs plombés dans le diffusé. Dans le rayonnement direct, le port des gants radio-atténuateurs plombés entraîne une augmentation de la dose – main, du fait des réglages automatiques des paramètres.

The work package 3 of the ORAMED project, Collaborative Project (2008-11) supported by the European Commission within its seventh Framework Programme, is focused on the optimisation of the use of active personal dosemeters (APDs) in interventional radiology and cardiology (IR/IC). Indeed, a lack of appropriate APD devices is identified for these specific fields. Few devices can detect low-energy X rays (20-100 keV), and none of them are specifically designed for working in pulsed radiation fields. The work presented in this paper consists in studying the behaviour of some selected APDs deemed suitable for application in IR/IC. For this purpose, measurements under laboratory conditions, both with continuous and pulsed X-ray beams, and tests in real conditions on site in different European hospitals were performed. This study highlights the limitations of APDs for this application and the need of improving the APD technology so as to fulfil all needs in the IR/IC field.

The 73 MeV proton beam line dedicated to ophthalmologic treatments at the ICPO was modelled at IRSN with the MCNPX Monte Carlo code. The ability of the model to adequately reproduce the measured proton absorbed dose distributions in a water phantom was shown in a previous work [ref:1]. Three[for full text, please go to the a.m. URL], PTCOG 48; Meeting of the Particle Therapy Co-Operative Group

The spallation of $^{56}$Fe in collisions with hydrogen at 1 A GeV has been studied in inverse kinematics with the large-aperture setup SPALADIN at GSI. Coincidences of residues with low-center-of-mass kinetic energy light particles and fragments have been measured allowing the decomposition of the total reaction cross-section into the different possible de-excitation channels. Detailed information on the evolution of these de-excitation channels with excitation energy has also been obtained. The comparison of the data with predictions of several de-excitation models coupled to the INCL4 intra-nuclear cascade model shows that only GEMINI can reasonably account for the bulk of collected results, indicating that in a light system with no compression and little angular momentum, multifragmentation might not be necessary to explain the data., Comment: 4 pages, 5 figures, revised version accepted in Phys. Rev. Lett

Some activities of EURADOS Working Group 9 (WG9) are presently funded by the European Commission (CONRAD project). The objective of WG9 is to promote and co-ordinate research activities for the assessment of occupational exposures to staff at workplaces in interventional radiology (IR) and nuclear medicine. For some of these applications, the skin of the fingers is the limiting organ for individual monitoring of external radiation. Therefore, sub-group 1 of WG9 deals with the use of extremity dosemeters in medical radiation fields. The wide variety of radiation field characteristics present in a medical environment together with the difficulties in measuring a local dose that is representative for the maximum skin dose, usually with one single detector, makes it difficult to perform accurate extremity dosimetry. Sub-group 1 worked out a thorough literature review on extremity dosimetry issues in diagnostic and therapeutic nuclear medicine and positron emission tomography, interventional radiology and interventional cardiology and brachytherapy. Some studies showed that the annual dose limits could be exceeded if the required protection measures are not taken, especially in nuclear medicine. The continuous progress in new applications and techniques requires an important effort in radiation protection and training.

Professional practices involving ionizing radiation are evolving and require an adequate individual monitoring of workers. Dosimetric techniques are also in constant development with, for example, new electronic personal dosimeters, particularly for neutrons, and a larger choice of available techniques (TLD, OSL, RPL) for passive dosimeters. The dosimetric workplace study is now mandatory. Among its objectives, it is aimed at to choosing passive and electronic techniques from the determination of the characteristics of the encountered radiation fields. The passive dosimeters distributed by the approved dosimetric services are satisfactory overall. Moreover, many different models, covering almost all needs, of electronic personal dosimeters are commercialised. To ensure the correct implementation of passive dosimetric techniques by the approved dosimetric services, it is important to organise intecomparisons. National and international intercomparisons are carried out regularly in order to account for new developments, evolution of practices and situations. © 2007 EDP Sciences.; Les activités utilisant des rayonnements ionisants évoluent et nécessitent une surveillance dosimétrique adaptée. Dans le même temps, les techniques dosimétriques ont également évolué offrant notamment un choix de dosimètres électroniques plus important en particulier pour les neutrons ainsi qu’une diversification des techniques utilisables (TLD, OSL, RPL) pour la dosimétrie passive de routine. L’étude de poste est devenue incontournable afin de déterminer la façon la plus réaliste les caractéristiques de l’exposition dont résulte, entre autres, le choix des techniques passives et opérationnelles. Les différents dosimètres passifs aujourd’hui proposés par les laboratoires agréés présentent des performances globalement satisfaisantes. Par ailleurs, il existe sur le marché de multiples modèles de dosimètres électroniques susceptibles de couvrir les besoins associés à la dosimétrie opérationnelle. L’organisation d’intercomparaisons constitue un élément important du dispositif de contrôle de la bonne mise en œuvre des techniques de dosimétrie passive par les laboratoires agréés et des performances des dosimètres actifs dans des conditions réalistes d’utilisation. De telles intercomparaisons sont réalisées périodiquement, tant à un niveau national qu’international, afin de prendre en compte les évolutions des matériels, des pratiques et du plus grand nombre de situations possibles.

Matière Nucléaire; The $^{92-96}$Zr nuclei were produced as fission fragments following the fusion reactions $^{28}$Si+$^{176}$Yb and $^{31}$P+$^{176}$Yb at 145 and 152 MeV bombarding energy, respectively. Prompt $\gamma$ rays emitted in the two reactions were detected with the EUROGAM II and EUROBALL IV arrays. Sequences of $\gamma$-ray transitions observed in coincidence were newly assigned to $^{93-96}$Zr. The previously known level schemes have been extended to higher excitation energies and higher spins. The experimental results are discussed in the framework of shell-model calculations with $^{88}$Sr assumed to be an inert core and the valence protons and neutrons filling the $\pi(2_{p1/2},1g_{9/2})$ and $\nu(2d_{5/2},3s_{1/2})$ orbitals.

Matière Nucléaire; The 121,123,125,127Sb nuclei have been produced as fission fragments in three reactions induced by heavy ions: 12C + 238U at 90 MeV bombarding energy, 18O + 208Pb at 85 MeV, and 31P + 176Yb at 152 MeV. Their level schemes have been built from gamma rays detected using the EUROBALL III and IV arrays. High-spin states of 123,125,127Sb nuclei have been identified for the first time. Moreover isomeric states lying around 2.3 MeV have been established in 123,125,127Sb from the delayed coincidences between the fission fragment detector SAPhIR and the gamma array. All the observed states can be described by coupling a d5/2 or g7/2 proton to an excited Sn core involving either vibrational states or broken neutron pairs. PACS

The experimental studies of the alpha-decaying excited states in 11, 13, 14C and 11, 12B have been performed using resonant particle spectroscopy techniques. Numerous excited states are observed in these nuclei. The results are in agreement with recent predictions of the presence of exotic cluster structures in these nuclei.

Experimental studies of the cluster structures in 9,10Be and 13,14C have been performed. Evidence for the α+5He decay of 9Be excited states, α+6He decays of 10Be∗ , α+9Be decay of 13C ∗ and for the decays of 14C ∗ into α+10Be were found. These decay processes indicate the cluster structures of the excited states. The results are compared with recent suggestions for the presence of molecule-like structures based upon α-particles and valence neutrons in Be and C isotopes., Eksperimentalno smo proučavali nakupinske strukture u 9,10Be i 13,14C. Našli smo α+5He raspad uzbuđenog stanja 9Be, α+6He raspad 10Be∗ , α+9Be raspad 13C ∗ te raspad 14C ∗ u α+10Be. Ovi procesi ukazuju na nakupinske strukture uzbuđenih stanja tih jezgri. Ishode mjerenja uspoređujemo s novim objašnjenjima o prisutnosti molekulama-sličnih struktura zasnovanim na α-česticama i valentnim neutronima u izotopima Be i C.