Le standard CEI 62471 décrit les limites d’exposition aux sources de rayonnements optiques incohérentes à large spectre, depuis l’UV jusqu’à l’IR en passant par le visible. Son application apparaît particulièrement justifiée pour l’évaluation de sources à LEDs blanches à luminophore, qui combinent une luminance élevée et un spectre riche en ondes courtes (bleu), ce qui expose potentiellement l’œil humain à un risque de lésions rétiniennes (Blue Light Hazard). En théorie, il s’agit simplement de mesurer la luminance énergétique spectrique de la source lumineuse à l’intérieur du champ visuel de l’œil en mouvement puis de la pondérer par la fonction décrivant le risque rétinien en lumière bleue. En pratique cependant, la mesure est assez faiblement répétable lorsque les sources en question n’offrent que des surfaces relativement inhomogènes du point de vue de la luminance. Des protocoles de mesures basés sur l’imagerie CCD permettraient probablement d’améliorer la répétabilité de la mesure. Cet article propose une première approche d’une méthode simple d’évaluation du risque par imagerie monospectrale.

CT scanning technology is a valuable tool to diagnose many diseases; however, the levelof the radiation dose is a source of concern, especially for children. CT scan systems anddose measurement methods have evolved over the years; but reported pediatric effectivedoses (EDs) have sometimes exceeded the annual dose limit recommended by the ICRP (1 mSvper year for persons under 18 years) (ICRP, 2007a).Efforts have been made to reduce organ doses and EDs by adjusting the scan parameters.This paper describes the determinants of the ED, and the dose reduction techniques inpediatric imaging from the early age of CT examinations until now. The firstepidemiological results regarding the associated risk of cancer are also brieflypresented.

Présents dans notre environnement les rayonnements électromagnétiques (EM) suscitent demultiples questions quant à leurs effets potentiels pour les porteurs de dispositifsmédicaux actifs implantés (DMAI). Le nombre croissant de porteurs d’implants médicaux, ycompris dans la population active, a entraîné un questionnement quant à leur comportementen présence d’un champ EM. L’interaction entre le corps humain et les champs EM restecomplexe et dépend de multiples facteurs tels que la fréquence, la puissance et lamodulation des champs. Nous présentons ici une revue de cette problématique dans le casdes champs EM basse fréquence.

This work suggests a classification of interventional radiology and cardiology proceduresbased on statistical analysis of operators’ finger doses measured in routine clinicalconditions. In total, 346 finger doses were measured and the observed mean finger dose perclass of procedure ranged from 0.03 mSv to 1.56 mSv for Cerebral, and Bone and Jointprocedures, respectively. The statistical analysis showed that the finger dose in Cerebralprocedures is significantly lower than in Cardiac procedures, which was significantlylower than the rest. Furthermore, finger doses in therapeutic procedures and in close oneswere significantly greater than in diagnostic procedures and in distal ones. This workalso studied the statistical relation between the use of ceiling-suspended shields orleaded gloves and the extremity dose. From the set of collected and analyzed data, afinger dose classification was proposed for different criteria: procedure type(diagnostics/therapeutic), proximity (close/distal), procedure class and access route.

The aim of this study is to provide data that increase knowledge about the possible health effects of exposure to 90Sr contaminant in drinking water. 90Sr detection in the mouse bone model plays an important complementary role with computational dosimetry in these investigations. S-value (absorbed dose per unit cumulated activity) calculations using Monte Carlo (MC) simulations, 90Sr detection by liquid scintillation β counting in the femur bone and X-ray microanalysis were carried out. The present work is focused on using MCNPX and its validation at a cellular level. The cytoplasm (Cy), nucleus (N) and 90Sr radiation source were simulated with the MC code MCNPX. Cells are assumed to be spherical, with the radii of the cell and cell nucleus ranging from 2 to 10 μm. The S-value (in Gy/Bq.s) calculations were provided for a 90Sr source distributed uniformly in the cell nucleus or cytoplasm and for two source-target combinations (t←s). A comparison between the calculated MC results and the MIRD values agreed very well since the relative deviations are less than 4%. The earliest results of X-ray microanalysis indicated that the 90Sr was below the detection limit (<0.1%) in the bone tissue. However, the measurements by liquid scintillation showed the presence of 90Sr in the femur bone.

The separate contributions of all source regions to organ doses from 131I and 123I administered to the bodywere calculated using voxelized reference phantoms. The photon and electron components oforgan doses were also evaluated for each source region. The MCNPX Monte Carlo particletransport code was utilized for dose calculations. All organs and tissues of male andfemale phantoms were taken into account as source regions with their correspondingcumulated activities. The results showed that cumulated activities assigned to sourceregions and inter-organ distances were two factors that strongly affected the contributionof each source to the organ dose. The major contribution of the dose to the main sourceregions arose from self-irradiation of electrons, while for nearby organs it was due tophotons emitted by the main source organs. In addition, self-irradiation plays animportant role in the dose delivered to most target organs for lower thyroid uptakes.

The observations made in Japan in 2011 after the Fukushima-Daiichi accident and those made in France, Italy, Greece and Austria in 1986 after the Chernobyl fallout, show that the development stage of orchard trees at the time of atmospheric deposition is a major factor determining the level of caesium contamination in fruits at harvest. Both data sets are shown to be consistent and enable one to estimate, for mobile elements in plants such as caesium, an aggregated transfer factor (expressed in Bq.kg-1 of fresh fruit per Bq.m-2 deposited on the ground surface) whose value strongly depends on the time elapsed between fallout and harvest. The Fukushima data set also enables one to estimate effective half-lives (expressed in days), which are helpful for predicting the decrease in fruit contamination with time. We found an average value of 200 days for the one-year period after radioactive fallout, which is quite consistent with values estimated from post-Chernobyl surveys.

This article proposes an assessment of the ingestion doses potentially received by peopleliving in the Japanese areas most severely affected by the radioactive deposits due to theFukushima nuclear accident. The assessment distinguishes two consecutive periods: thefirst 2 months (March 15th to May 15th 2011) and the rest of the year 2011, according tothe two main foodstuff contamination periods identified (Renaud et al.,2013). On the basis of the worst-case hypothesis that can reasonably be made, theestimated doses are much lower than they might have been in other circumstances, onaccount of generally moderate levels of contamination for most foods, early evacuation ofthe most severely affected areas and the consumption bans ordered by the Japaneseauthorities. Thus, a single ingestion of 100 g of leafy vegetables in the early days by aone-year-old child living in non-evacuated localities near Iitate and Kawamata could haveled to an equivalent dose to the thyroid of about 25 mSv; and to a thyroid dose of about140 mSv for the rather unrealistic scenario of a daily consumption. Because of the rapiddecrease in the contamination of vegetables and a much weaker contamination of othercrops, and thanks to measures taken by the authorities (prohibition of consumption, use ofcertain fodder, etc.), the ingestion doses potentially received during the remainder ofthe year 2011 are estimated to be below 1 mSv. In the event that sales limits would havebeen ignored, only repeated consumption of mushrooms would have led to doses above thatlevel. Even with the worst-case hypotheses, the doses potentially caused by ingestion aremuch lower than those resulting from outdoor exposure to radioactive deposits:approximately several millisieverts in a year for the population living in thenon-evacuated localities near Iitate and Kawamata.

La fabrication de verre plombé n’a pas encore été développée en Colombie, ce qui entraîne des lacunes dans la recherche d’améliorations des composants pour la protection radiologique. Le Groupe de Physique Médicale de l’Université Nationale de Colombie a donc initié une étude en vue de développer différents échantillons de verre plombé qui soient adaptés à une utilisation comme blindage contre les rayonnements ionisants. Les caractéristiques optimales ont été trouvées pour une concentration de 50 % d’oxyde de plomb (PbO) dans un verre de plomb-silicate. Un pourcentage de PbO supérieur entraîne des difficultés techniques et une diminution de la clarté du verre. Pour cette fraction molaire nous avons trouvé un coefficient d’absorption linéaire de 0,35 cm-1, c’est-à-dire que pour une énergie de 662 keV un centimètre de ce verre correspond à 3,0 mm de plomb pur; avec cette même énergie la couche de demi-atténuation (CDA) de l’échantillon est égale à celle du ciment ferreux utilisé couramment dans les blindages radiologiques. Enfin il a également été observé que l’application d’une couche d’air de 1 cm entre les lames de verre diminue la transmission des photons jusqu’à 20 % pour le verre contenant 40 % de plomb.

Interventional cardiologists (ICs) are repeatedly exposed to scattered ionising radiationduring the cardiac procedures they perform, and radiation protection is an important issuefor these medical professionals. The use of radiation protection tools is particularlyrelevant to this population. SISERI (Système d’Information de la Surveillance del’Exposition aux Rayonnement Ionisants, that is, an information system for monitoringexposure to ionising radiation) is a register that stores personal dosimeter readings fordosimetric monitoring. This paper, based on data for a sample of French ICs from theO’CLOC epidemiological study, aims to provide an overview of the use of radiationprotection equipment and dosimetric devices reported by ICs in a specific questionnaire aswell as the dosimetric information found in the SISERI database for this population.Material and Methods − Annual information on interventional cardiology activity for theperiod from 01/01/2005 to 31/12/2009 was collected in an occupational questionnaire. ICswere asked to report the frequency in which they used individual dosimeter and radiationprotection tools (lead apron, thyroid shield, eyewear or face shield, ceiling-suspendedshield) as follows: never (0% of the time), occasionally (<50%), regularly (>50%), always (100%). We retrieved theirmedical radiation exposure information (monitored status and monthly effective doses) fromthe SISERI database for the period 2005−2009. Results – Information for 132 ICs (mean age in2005 = 46 ± 7 years) wasavailable. All ICs reported routine use of lead aprons, in contrast to their occasionaluse of lead eyewear or face shields. During the study period, 49% reported systematic useof personal dosimeters, and 21% more regular use. On the other hand, 18% never used adosimeter during this period. The SISTERI database included 92% of our population, 73% ofwhom had complete annual dose monitoring in SISERI (corresponding to at least 11 monthsper year of recorded data). Conclusion − ICs must improve their regular use ofradiation protection tools and systematic use of personal dosimeters. The SISERI databaseis an appropriate tool for flagging those medical professionals exposed to ionisingradiation. Better awareness of the importance of radiation protection rules in thispopulation, in particular, systematic dosimeter use, remains an important issue.

The Monte Carlo MCNPX code is used to calculate the scatter fraction, making it possible to assess the scattered dose equivalent rate. Two materials are considered for the phantom: water and steel. The calculations are performed by considering beams of monoenergetic photons (in the range 10 keV to 10 MeV) and bremsstrahlung photons resulting from the interaction of electrons (30–900 keV) on a tungsten target. The variation of the scatter fraction is investigated as a function of the primary photon energy, the beam area at the phantom surface, the scattering angle, and filtration of the bremsstrahlung radiation. We note the shortcomings of the ISO standard issued in 2011, which does not take into account the beam area at the phantom surface, the scattering angle or the scattering materials, thus producing inconsistencies with the computed values given in this study and in the literature. Our values for the scatter fraction are comparable with those given in the literature (e.g. NCRP). As regards the bremsstrahlung radiation, we note the influence of filtration, in particular at low energies. The scatter fractions given here are compatible with the calculation of the ambient dose equivalent, whereas in the literature, they are systematically used for the calculation of air kerma rates. We also obtain scatter fractions for water that are higher by a factor of 5 compared with steel.

The term “dose constraint” has been used in radiological protection since 1990. Itspractical application has varied from country to country to the present day. The authorsof this paper believe that it is an underestimated tool for the purpose of radiologicalprotection. This study aims to estimate local dose constraints for workers in conventionalnuclear medicine and radiology departments, on the basis of doses received in the last 3to 4 years by different groups of workers. The levels of exposure to employees of thenuclear medicine department correspond well to levels in other countries, but foremployees belonging to the radiology department, the levels are significantly lower.Unification of the practical application of dose constraints and legislation concerningtheir specific values would increase the relevance and effectiveness of these operationalunits. This is a playing field for radiation safety officers for the determination andwidespread publication of local dose constraints in their particular medical departments.

Le code de la santé publique et notamment l’arrêté du 11 janvier 2007, relatif auxlimites et références de qualité des eaux brutes et des eaux destinées à la consommationhumaine, fixe quatre indicateurs de la qualité radiologique des eaux du robinet(l’activité αglobale, l’activité β globale, l’activité du tritium et la dose totaleindicative), ainsi que des valeurs guides et des références de qualité. Les chroniquesissues de la surveillance des eaux filtrées du Rhône aval montrent que, si laradioactivité d’origine naturelle demeure bien évidemment constante au cours du temps, lesniveaux de contamination radioactive d’origine artificielle ont fortement diminué à partirdu début des années 90, de 10 à 100 fois suivant les radionucléides. Les donnéessoulignent également qu’aucune des limites d’activités α globale, β globale et en tritium n’aété dépassée dans l’eau filtrée du Rhône aval au cours de l’ère industrielle nucléaire.Les doses totales indicatives (DTI) calculées à partir des prélèvements d’eau filtrée duRhône aval (canal Philippe Lamour – Réseau hydraulique régional propriété de la régionLanguedoc Roussillon géré par BRL), de l’Orb et de l’Hérault effectués en 2011 sont trèsinférieures à la valeur de référence de 100 μSv/an. La contribution à la DTI des radionucléidesartificiels détectés dans ces hydrosystèmes est en outre négligeable (<0,01 %).

We calculated mass attenuation coefficients, effective atomic numbers and Kerma relative to air for human organ and tissue substitutes (i.e.wax, plastic and polymer materials). The effective atomic numbers of the tissue substitutes were calculated by the direct method, interpolation method, Auto-Zeff software and single value XMuDat program and then compared. The calculated effective atomic numbers were also compared with available experimental data and a good agreement was observed. A large difference in effective atomic numbers calculated by the direct and interpolation methods was observed in photoelectric and pair-production regions. The direct method was found to be appropriate for effective atomic number computation in low-(>10 keV) and medium-(0.1 ≤ E ≤ 10 MeV) photon energy regions. Kerma relative to air of the selected tissue substitutes was found to be dependent upon the atomic number and element compositions, which show a sharp peak due to K-edge absorption.

Transfer factors of 226Ra, 210Pb and 210Po from soilcontaminated with naturally occurring radioactive materials (NORM) in oilfields to somegrazing plants were determined using pot experiments. Contaminated soil was collected froma dry surface evaporation pit from a Syrian oilfield in the Der Ezzor area. Five types ofplants (Atriplex halimus L., Atriplex canescens, Atriplex Leucoclada Bioss,Alfalfa and Bermuda grass) were grown and harvested three times over two years.The results show that the mean transfer factors of 226Ra from the contaminatedsoil to the studied plant species were 1.6 × 10-3 for Atriplexhalimus L., 2.1 × 10-3 for Atriplexcanescens, 2.5 × 10-3 for Atriplex LeucocladaBioss, 8.2 × 10-3 for Bermuda grass, and thehighest value was 1.7 × 10-2 for Alfalfa. Transferfactors of 210Pb and 210Po were higher than 226Ra TFs byone order of magnitude and reached 7 × 10-3, 1.1 × 10-2,1.2 × 10-2, 3.2 × 10-2 and 2.5 × 10-2for Atriplex halimus, Atriplex canescens, Atriplex Leucoclada Bioss, Bermuda grassand Alfalfa, respectively. The results can be considered as basevalues for transfer factors of 226Ra, 210Pb and 210Po insemiarid regions.

The measurement performances of in vivo monitoring vehicles were studiedconsidering an increase in the radiological background in areas where the population isnot evacuated after a nuclear accident. The study focused on 137Cs and 131I Detection Limits (DLs) andcorresponding doses, for adults and one-year-old children. These DLs for groundcontamination were obtained experimentally using a grid of point sources. Then, the DLsand doses were calculated using the experimental data and a safety factor for two accidentscenarios. For these scenarios the 137Cs DL corresponds to a committed effective dose of0.02 mSv. The 131IDL corresponds to committed equivalent thyroid doses of 3 mSv (adult) and 30 mSv(one-year-old child). To guarantee a 45 mSv thyroid equivalent dose assessment for thechild the surface activity of 131I +132I +133I should be below 1.6 MBq/m2. This study shows that thevehicles can operate in a contaminated area where the population is not evacuated.However, in such a case, the contamination level outside and inside the vehicle should bekept stable to guarantee efficient body counting.