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One of the goals of the COVICOCEPAD project is to develop a mathematical model of tuned liquid dampers (TLD) devices. This new model will take into account the damping forces resisting the actions resulting from the viscous interactions between the liquid and its rigid container, the hydrodynamic head losses subsequent to orifices passing and the internal viscosity of the liquid. To calibrate the mathematical models full scale tests on shaking table are being performed. A performance evaluation of the TLD devices will be accomplished by the comparison between the behaviour of a specific structure with and without passive protection. This work addresses on the possibility of exploiting the liquid sloshing motion in tanks for specific vibration control purposes of civil engineering structures. Analytical, numerical and experimental issues are referred and the test steel frame is presented.

Gamma radiation in the environment today mainly originates from naturally occurring radionuclides, but anthropogenic radionuclides, such as 137Cs, contribute in some areas. In order to assess population exposure in case of fallout from nuclear weapons (NWF) or accidents, knowledge and monitoring of external gamma radiation and radionuclide concentrations in the environment is important. For this purpose 34 sampling sites were established in western Sweden and repeated soil sampling, field gamma spectrometry (in situ measurements), and dose rate measurements were performed. The variations in the activities between the different sampling occasions were found to be quite large. The naturally occurring radionuclides were the main source of outdoor dose rates. The uranium and thorium decay series contributed about equally to the total dose while the contribution from 40K was somewhat higher. The dose rates were mainly correlated to the ground cover, with higher levels on asphalt and cobble stones than on grass. The large scale deposition densities from NWF and the Chernobyl accident could be relatively well estimated by a model including the amount of precipitation and measured deposition at few reference sites. The deposition density from nuclear weapons tests in Sweden between 1962 and 1966 was found to be 1.42-2.70 kBq/m2 and the deposition density from Chernobyl in western Sweden ranged between 0.82-2.61 kBq/m2. The vertical migration of 137Cs was studied at the sampling sites in western Sweden and a solution to the convection–diffusion equation (CDE) was fitted to depth profiles. The vertical migration of 137Cs was found to be very slow and diffusive transport was dominant at most locations. The apparent convection velocity and diffusion coefficient were found to be 0–0.35 cm/year and 0.06–2.63 cm2/year, respectively. The average depth of the maximum activity was 5.4±2.2 cm. The fitted depth distributions for each location were used to correct in situ measurements and the results agreed relatively well with the 137Cs inventories in soil samples. A widespread deposition of radionuclides was caused by the Chernobyl accident and parts of Sweden were highly affected. Today, approximately 20 years since the latest deposition, 137Cs can still be measured in the environment and contributes to additional doses to people. However, today people generally spend much time in their dwellings, and therefore, the radiation environment indoors is more important for the personal exposure. Dwelling and personal dose rate measurements in western Sweden (means: 0.099±0.035 µSv/h and 0.094±0.017 µSv/h, respectively) showed that concrete dwellings yield higher dose rates than those of wood. Measurements in a region with a high 137Cs deposition (Hille in eastern Sweden) showed somewhat higher dose rates in wooden dwellings than in western Sweden (0.033 µSv/h and 0.025 µSv/h higher, respectively). The additional contribution from the Chernobyl 137Cs fallout in Hille was estimated to be about 0.2 mSv/year.

Dental panoramic radiograph in Indonesia has been widely used. Modern diagnostic imaging equipment with minimum radiation is still very limited. One of the conditions in nuclear safety law, UU 10/1997, is an optimization of all radiation sources with DRL through skin dose measurements. In Indonesia, the national DRL has not been established yet, and there were no reports on the study of panoramic skin dose in Indonesia. The aim of this preliminary study was to obtain a panoramic skin dose radiation as reference to establish DRL in Indonesia. Panoramic radiographs of sixteen female and fifteen male patients, aged 4 – 48 years, were taken using the standard conventional method, with TLD chips attached in location groups. The chips were then read with the detector and integrator of BATAN, in high and low temperature condition at the same time. It was revealed that behind the right and left ear were the regions with the highest radiation dose received, followed by the back of the neck, left jaw, right jaw, and chin. The result of this study has shown the importance of DRL in Indonesia since the use of modern diagnostic imaging equipement that limits radiation dose to the minimum level is still very limited.

Patient dose in diagnostic radiology is usually expressed in terms of organ dose and effective dose. The latter is used as a measure of the stochastic risk. Determinations of these doses are obtained by measurements (Thermoluminescent dosemeters) or by calculations (Monte Carlo simulation). Conversion factors for the calculation of effective dose from dose-area product (DAP) values are commonly used to determine radiation dose in conventional x-ray imaging to realize radiation risks for different investigations, and for different ages. The exposure can easily be estimated by converting the DAP into an effective dose. The aim of this study is to determine the conversion factor in procedures by computing the ratio between effective dose and DAP for fluoroscopic cardiac procedures in adults and for conventional lung and urography examinations in children. Thermoluminescent dosemeters (TLD) were placed in an anthropomorphic phantom (Alderson Rando phantom) and child phantom (one year old) in order to measure the organ dose and compute the effective dose. A DAP meter was used to measure dose-area product. MC calculations of radiation transport in mathematical anthropomorphic phantoms were used to obtain the effective dose for the same conditions with DAP as input data. The deviation between the measured and calculated data was less than 10 %. The conversion factor for cardiac procedures varies between 0.19 mSvGy-1 cm-2 and 0.18 mSvGy-1 cm-2, for TLD respective MC. For paediatric simulation of a one year old phantom the average conversion factor for urography was 1.34 mSvGy-1 cm-2 and 1,48 mSvGy-1cm-2 for TLD respective MC. This conversion factor will decrease to 1.07 mSvGy-1 cm-2 using the TLD method, if the new ICRP (ICRP Publication 103) weighting factors were used to calculate the effective dose. For lung investigations, the conversion factor for children was 1.75 mSvGy-1 cm-2 using TLD, while this value was 1.62 mSvGy-1 cm-2 using MC simulation. The conversion value increased to 2.02 mSvGy-1 cm-2 using ICRP’s new recommendation for tissue weighting factors and child phantom.

The Thermoluminescence Personal Dosimetry Laboratory of the University of Costa Rica provides dose measurements for around 90% of occupational radiation workers in the country. The assessment of doses to workers routinely exposed to external sources of radiation constitutes an integral part of any radiation protection programme and helps national authorities to ensure acceptably safe and satisfactory radiological conditions in workplaces. Harshaw Readers Model 4000 and 4500, dosimeter holders Type 8814 with TLD-100 in 0110 cards and loose TLD-100 chips are used to monitor personal dose equivalent, Hp(10) and Hp(0.07). In order to provide a reliable measurement of the operational quantities, a study was undertaken to verify the fulfillment of international requirements in our system (Model 4500 with cards) against the Thermoluminescence dosimetry systems for personal and environmental monitoring CEI IEC 61066 (1991 -2012). The type tests performed were nine in total: batch homogeneity, reproducibility, linearity, detection threshold, effect of climate conditions on reader, effect of light exposure on dosimeters, isotropy, transient voltage and dropping on dosimeters. A Cesium-137 source was used to irradiate the dosimeters and all procedures follow the indications given on the standard. Results showed that all IEC criteria were met by our Laboratory. Acceptable uncertainties were also studied under the ICRP recommendations; the analysis of the Trumpet Curve was done with satisfactory results (for doses above 0.5 mSv; quotient of measure to real dose less than 3%). For purposes of accreditation (ISO/IEC 17025:2005) and performance testing this work is very relevant since the University of Costa Rica wants to establish a solid individual monitoring programme for external radiation exposure that will provide users, registrants, licensees and regulatory bodies with information that can be used for the optimization of protection and dose limitation of Costa Rican workers UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigación en Ciencias Atómicas Nucleares y Moleculares (CICANUM)

The international community is facing the task of the monitoring of environmental radiation because of its potential increases due to human activities. Monitoring networks have been established to provide a record of natural background radiation as well as to measure any radiation releases from facilities. Thermoluminescence and radiophotoluminescence solid state dosimeters are important elements of such networks and are widely used passive detectors for environmental monitoring. Environmental dosimetry systems have to fulfil the requirement to measure the man-made contribution to environmental radiation (1:10). The monitoring has to be carried out under variable environmental conditions (UV sunlight, humidity, temperature). Performance testing and procedural specifications may be found in national and international standards. Various high sensitivity dosimeter systems based on LiF:Mg, Cu, P, CaF2:Mn and Al2O3:C along with TLD-700 were investigated in laboratory and field tests. The following dosimetric characteristics of the recently developed SC-1 flat RPL glass dosimeters with FGD-202 reader for environmental dosimetry were also investigated: uniformity/batch homogeneity, reproducibility, linearity, detection threshold, energy dependence in air, on phantom and in water as well as the light sensitivity. All characteristics of RPL dosimeters investigated fulfil the requirements of the new IEC 61066:2006 Standard for personal and environmental dosimetry. The author proposes to extend the IEC Standard for personal and environmental monitoring also to RPL (and other) passive solid state dosimeters. To reach international standards and to improve the environmental dosimetry method there is a need for intercomparisons. Several large-scale international intercomparisons were organised for passive environmental dosimeter systems. Recently, a new intercomparison of environmental dosimeters is being organised for a few participants. The protocol and the aim of the intercomparison will be discussed.

Radiophotoluminescent (RPL) glass dosimetry system is applicable for measurement of radiation dose of X-rays and gamma rays, using a flat silver activated phosphate glass RPL detectors. They are under permanent development, so the aim of this work was to investigate RPL glass dosimeters for application in environmental monitoring according to the IEC Standards. The following dosimetric characteristics of the recently developed SC-1 flat RPL glass dosimeters with FGD-202 reader for environmental dosimetry were investigated: uniformity/batch homogeneity, reproducibility, linearity, detection threshold and energy dependence in air, and on phantom. The characteristics of RPL dosimeters investigated in this work match the requirements of the international standards for environmental monitoring.

In addition to gamma spectrometry in situ and direct dose rate measurements, TLD passive dosemeters are used to monitor the ionizing radiation fluctuation of the environment in spite of their great uncertainties. We have used the active electronic dosemeter (AED) which measures the dose rate to, for the same purpose and on the same measuring sites where the TLD-s were put on in order to compare the accummulated dose obtained by both measuring devices. Measurements were performed for more than three years and on several environmental sites of concern. The results obtained encouraged us to use the AED as a monitoring mobile measuring station.

Köztudott, hogy a mesterséges sugárforrásokból származó lakossági sugárterhelés több, mint 90%-a az orvosi besugárzásokból ered, ezen besugárzások túlnyomó része pedig a dignosztikai (röntgen, CT stb.) eljárásokból származik. Ezért a diagnosztikai eljárásoknál kapott betegdózis ismerete és csökkentése alapfontosságú a sugárvédelem szempontjából különösen tekintettel a gyermekgyógyászati röntgen besugárzásokra. Termolumineszcens (TL) és radiofotoluminescens (RPL) doziméterek megfelelő kalibrálás és a nemzetközi szabványban (IEC Standard 2006) előírt tesztelés után jól alkalmazhatók az orvosi diagnosztikában. Meghatároztuk tüdőröntgen felvétel esetén 5 korcsoportba beosztott (0-15 év) 50 gyermekpaciens sugérterhelését profil és PA felvételnél a következő testrészeken: hát, sternum, pajzsmirigy, hónalj, szem és gonád. Az effektiv dózist különbözó szerveken speciális gyerekfantomon mértük meg TL doziméterrel. A mért dózisértékekből megbecsültük a sugárkárosodás következtében fellépő leukémia, tüdőrák és genetikai károsodás kockázati tényezőjét. A fej kompjuter-tomográfiás vizsgálata során meghatároztuk a felnőtt beteg fejének különböző részein (szem, homlok, stb) kapott dózist. Tanulmányoztuk a dózisvariációt befolyásoló tényezőket (készülék paraméterek, beteg jellemzői, stb.). A beteg sugárvédelmének szempontjából a röntgen diagnosztikai eljárások optimális feltételeinek meghatározásánál nemcsak a képminőséget, hanem az orvosi besugárzásból eredő dózisértéket is figyelembe kell venni. Ez rendszeres dózisméréssel és az orvosi, technikai személyzet folyamatos továbbképzésével érhető el. Ezt a munkát részben a Horvát Tudományos, Művelődési és Sport Minisztérium valamint a Chiyoda Technol Corporation cég, Japán támogatta.

The aim of this study was to compare the TL properties (sensitivities, structure of the glow curves etc.) of newly developed Li2B4O7, Li2B4O7:Cu single crystals to the well known Al2O3:C single crystal dosimeters using gamma and fast neutron (14.5 MeV) irradiation in mGy dose range. The transparent and colourless slits (6mm x 6 mm x 1 mm) of undoped and doped, lithium tetraborate single crystals were prepared for photoluminescent purposes by Czochralski method in Ukraine.( Institute of Electron Physics, Uzhgorod). The following irradiations of TLDs were performed: a) gamma with 137Cs source in Secondary Standard Dosimetry Laboratory, b) 14.5 MeV fast neutrons. Fast neutrons were produced by Texas Nuclear Corporation 300 keV electrostatic accelerator (neutron generator) at Ruđer Bošković Institute using T(d, n)α nuclear reaction. The gamma component was measured by GM counter in the fast neutron irradiation field. The results will be analysed from the aspect of the possibility of discrimination of different components with TLDs in the mixed fast neutron irradiation field. Since in the field used here practically there are no thermal neutrons, the results from this work give valuable data for using these detectors in mixed field.

Diagnostic radiology is the main source of exposure of the population to man-made ionising radiation. The X-ray examinations of thoracal organs occupy the first place, particularly in childhood. To reduce the risk from exposure in diagnostic X-ray examinations, especially paediatric diagnostic, the knowledge of the absorbed doses in tissue is important. Long-term and highly statistical dose measurements on patients and various phantoms during thoracal diagnostics of children with various dosimetric systems were described in the literature. The aim of the recent work was to measure the skin doses during X-ray diagnostic of lung of children, first of all on the eyes, the thyroid gland and gonades with radiophotoluminescence glass (RPL) and thermoluminescence (TL) dosimeters. Eyes and thyroid are radiosensitive organs and they are in the primary beam during the diagnostic treatment. In addition to dosimetry measurements cytogenetically status of patients was investigated. In the study special attention was given for use of adequate protection devices. Radiation risks associated with paediatric patients may not be considered as trivial. The present data should be taken into adequate radiation protection during X-ray examination, although we expected very low doses. On the basis of the results some proposals for the protocol of X-ray diagnostic of thorax will be given.

Titelblatt und Inhaltsverzeichnis Einleitung Material und Methoden Ergebnisse Diskussion Zusammenfassung Literaturverzeichnis, ZIEL: Untersuchung der Strahlenrisiken von Interventionalist,Assistentin und Sonographeur bei der Anlage eines transjugulären intrahepatischen portosystemischen Shunts (TIPS) durch Erfassung der Teilkörperdosis im Vergleich zu den Dosisgrenzwerten.Außerdem erfolgte eine Bewertung zusätzlicher Strahlenschutzabschirmungen. MATERIAL UND METHODE: Bei 30 TIPS wurden mit Thermolumineszensdetektoren (TLD) , die an den Augenbrauen, beidseits der Schiddrüse,den Handrücken,den Unterschenkeln über der Tibia,der Brust,am Nabel und der Symphyse fixiert waren,die Oberflächendosen gemessen.Die gemessenen Werte galten als konservative Abschätzung für tiefer liegende Organe.Bei den ersten 15 Interventionen trugen Interventionalist,Assistentin und Sonographeur nur eine Bleischürze,bei den nächsten 15 Interventionen darüberhinaus einen Schilddrüsenschutz. Außerdem wurde eine Bleiglasscheibe zwischen Interventionalist und dem Bildverstärker positioniert,ein Unterkörperschutz zwischen Sonographeur und Röntgenröhre befestigt und der Sonographeur trug an der, den Schallkopf haltenden Hand,einen bleiarmierten Handschuh. ERGEBNISSE: Die höchste Oberflächendosis ohne zusätzliche Schutzmaßnahmen wurde beim Interventionalisten,der Assistentin und dem rechts vom Patienten stehenden Sonographeur an der rechten Tibia,beim links stehenden Sonographeur an der linken Tibia gemessen. Die Teilkörperdosis des roten Knochenmarkes,die vereinfachend der Oberflächendosis an der Tibia gleichgesetzt wurde,erlaubte in Hinblick auf die Einhaltung der Dosisgrenzwerte maximal 12,18,62 bzw.32 TIPS-Interventionen pro Jahr.Bei den Interventionen mit Dauerschutzeinrichtung, Schilddrüsenschutz,Bleihandschuh und Unterkörperschutz wurde die höchste Oberflächendosis beim Interventionalisten und der Assistentin an der rechten Tibia und beim Sonographeur an der linken Hand gemessen. Die Teilkörperdosis für das rote Knochenmark,die vereinfachend der Tibia-Oberflächendosis gleichgesetzt wurde,erlaubte dem Interventionalisten maximal 15 und der Assistentin maximal 21 TIPS pro Jahr. Der links stehende Sonographeur hätte über 750 und der rechts stehende 312 TIPS-Interventionen durchführen können.Durch die zusätzlichen Strahlenschutzmaßnahmen wurde das stochastische Strahlenrisiko für den Interventionalisten um 35%,die Assistentin um 41% und den Sonographeur um 65% reduziert. SCHLUSSFOLGERUNG: Der Unterkörperschutz hat seine entscheidene Bedeutung in der Einhaltung der Dosisgrenzwerte,da das Knochenmark der Tibia ohne Unterkörperschutz einer hohen Dosis ausgesetzt ist., AIM: Investigation of the risks of radiation exposure among an interventionalist, assistant and sonographer during installation of a transjugular intrahepatic portosystemic shunt (TIPS) by assessment of the fractional dose in comparison to dose threshold values. Moreover, an evaluation of additional measures towards radiation shielding protection was undertaken. MATERIALS AND METHODS: Among 30 TIPS, the surface doses were measured using thermoluminescence detectors (TLD) which were attached to the eyebrows, both sides of the thyroids, backs of the hands, lower legs over the tibia, the breast, umbilicus and symphysis. The values measured were considered to represent a conservative estimation for organs beneath these sites. During the first 15 interventionists, the interventionalist, assistant and sonographer wore only a lead apron, whereas in the next 15 interventionists, they wore a thyroid protecting shield as well. Furthermore, a lead glass plate was positioned between the interventionist and the video amplifier, a protection of the lower part of the body was placed between the sonographer and the X-ray tube, and the sonographer wore a lead protecting glove on the hand used to hold the accustic header. RESULTS: The highest surface dose without any additional protection was measured among the intervestionalist, the assistant and the sonographer standing to the right of the patient, on the left tibia. The partial body dose of the red bone marrow considered upon simplification to be represented by the surface dose of the tibia allowed a dose threshold value compliance of a maximum of 12, 18, 62, that is, 32 TIPS interventions per year. For the interventions with permanent protection, thyroid protection, lead protecting gloves and lower body protection, the highest surface dose for the interventionalist and assistant was measured in the right tibia, and for the sonographer in the left hand. The partial body dose, considered upon simplification to be represented by the surface dose of the tibia, allowed the interventionalist a maximum of 15, and the assistant a maximum of 21 TIPS per year. The sonographer, when standing to the left could have carried out more than 750 TIPS, and when standing to the right, 312 TIPS. By use of the additional protective measures, the stochastic risk of radiation was reduced by 35% for the interventionalist, 41% for the assistant, and 65% for the sonographer. CONCLUSIONS: Protection of the lower body had a decisive effect on the compliance of dose threshold values, because without protection of the lower body, tibia bone marrow is subject to a high dose.

Radioiodine has been used in nuclear medicine for the treatment of thyroid diseases such as Thyroid Cancer and Thyrotoxicosis for many years. The treatment renders the patient radioactive. To minimize the dose to the patients’ relatives and the general public, restric-tions are imposed on the behaviour of the patient. This project presents the person dose equivalents actually received by family members of radioiodine patients following such restrictions. The family members wore hospital ID-bands on left and right wrists for up to four weeks. Each ID-band contained two LiF: Mg, Ti Thermo Luminescence Dosimeters (TLD) calibrated to measure air kerma. The TLDs were analysed and a total person dose equivalent received by the relative was calculated from the measured air kerma values. The results were compared to the dose constraints imposed by The Swedish Radiation Protection Authority (SSI FS 2000:3) in order to confirm that the new set of restrictions used at Karolinska University Hospital Huddinge maintains the dose to family members below the applicable limits. A total number of 22 relatives were recruited, 8 elderly, 7 adults and 7 children. Of the recruited relatives 4 (2 adults, 2 children) were excluded from the study as they had lost their dosimeter ID-bands or had other reasons not to participate in the study. This leaves the number of relatives used for data analysis at 18 individuals (8 elderly, 5 adults and 5 children) with a min age of 10 years and max age of 80 years. The observed average person dose equivalent of 0.43 mSv (max, 1.27; min, 0.12) indi-cates that the new method of individualised restriction used at Karolinska University Hospital Huddinge work as desired in keeping the dose to family members at an accept-able level. The accuracy of the clinical study has been shown to depend greatly on the method by which the dose is investigated but also on the properties of the TLD material used. There is a potential underestimation of air kerma due to fading of up to 30 %. In addition there are contributing uncertainties from both the calibration method and the conversion to person dose equivalent with the combined uncertainty estimated to be 14%.

Purpose: The purpose of this analysis was to investigate dose distribution of Three Dimensional Conformal Radiation Therapy (3DCRT), Intensity Modulated Radiation Therapy (IMRT) and Volumetric Modulated Arc Therapy (VMAT) for Head and Neck cancer using 3-dimensional PRESAGE® dosimeter. Method: Computer Tomography (CT) scans of Radiological Physics Center (RPC) Head and Neck anthropomorphic phantom with both RPC standard insert and PRESAGE® insert were acquired separated with Philipp’s CT scanner and both CT scans were exported via DICOM to the pinnacle treatment planning system (TPS). Each plan was delivered twice to the RPC phantom first containing the RPC standard insert having Thermoluminescent detectors (TLD) and film dosimeters and then again containing the PRESAGE® insert having three dimensional dosimeter (PRESAGE®) by using a Varian True beam linear accelerator. After irradiation, the standard insert including point dose measurement (TLD) and planner GafChromic® EBT film measurement was read using RPC standard procedure. The 3D dose distribution from PRESAGE® was read out with the Duke Midsized optical scanner dedicated to RPC (DMOS-RPC). Dose volume histogram (DVH), mean and maximal doses for organ-at-risk (OARs) were calculated and compared among each Head and Neck technique. The prescription dose was same for all Head and Neck radiotherapy techniques which was 6.60 Gy per friction. Beam profile comparison and gamma analysis were used to quantify agreement among film measurement, PRESAGE® measurement and calculated dose distribution. Quality assurances of all plans were performed by using ArcCHECK method. Results: VMAT delivered the lowest mean and maximal doses to organ at risk (spinal cord and parotid) than IMRT and 3DCRT. Such dose distribution was verified by absolute dose distribution using TLD system. 2D gamma 5%/3 mm criteria of Pinnacle vs. EBT2 film 3DCRT (92.34%), IMRT (92.3%) and VMAT (96.63%) in axial plan respectively. It was also found that agreement between PRESAGE® and pinnacle along the axial, sagittal and coronal plans VMAT agreement was better than IMRT and 3DCRTplan excludes a 7 mm rim at the edge of the dosimeter using 2D gamma map criteria (±5%/3 mm) with 5% threshold dose. Profile showed good agreement for all plans between film, PRESAGE® and pinnacle. 3D gamma was performed for planning target volume (PTV) and organ at risks (OARs) VMAT and 3DCRT endow with better agreement than IMRT. Conclusion: VMAT delivered lowered mean and maximal doses to organ at risk and better PTV coverage. TLD, EBT film and PRESAGE® dosimeter has suggested that VMAT would be superior modality for the treatment of Head and Neck cancer than IMRT and 3DCRT.

The objective of this thesis is to develop the modelling of the nuclear heating of the experimental devices of the future Jules Horowitz material testing reactor (RJH). The strong specific nuclear power produced (460 kW/l) induces intense photonic fluxes which cause heating and large gradients in temperature. The design studies of the experimental devices require an accurate knowledge of these gradients. A priori, we estimate that there are large uncertainties on gamma heating calculations to about 30% (2σ). They are mainly due to the lack of knowledge about gamma emission yields and spectra and secondly come from the mismodelling of the gamma response function. In order to specify this uncertainty, a set of integral dose measurements using different kinds of TLD and a micro-ionization chamber are carried out in the UO2 core of the MINERVE research reactor. The comparison between calculated and measured integral (prompt plus delayed) gamma-ray absorbed doses in TLD shows that calculation constantly underestimates the measurement with C/E = 0.72 ± 15% (k = 2) of total uncertainties. The systematic bias observed is partially attributed to a lack of gamma-ray emission data in basic nuclear data libraries used. A Bayesian method of adjustment is developed in order to re-estimate the principal components of the gamma heating and to transpose the results obtained to the devices of the RJH. This study made it possible to reduce significantly the uncertainties on the determination of the gamma heating from 30% to 15% (2σ).; L'objectif de cette thèse est de développer la modélisation des échauffements nucléaires au niveau des dispositifs expérimentaux du futur réacteur d'irradiation technologique Jules Horowitz (RJH). La forte puissance nucléaire spécifique produite (460 kW/l) induit des flux photoniques intenses qui provoquent des échauffements et des gradiants de température importants, qu'il est nécessaire de maîtriser dès la conception. Or, les calculs d'échauffement sont pénalisés par des incertitudes rédhibitoires estimées à une valeur enveloppe et majorante de 30% (2 sigma) provenant des lacunes et incertitudes des données d'émission gamma présentes dans les bibliothèques de données nucléaires de base. Le programme expérimental ADAPh vise à réduire ces incertitudes. Des mesures par détecteurs thermoluminescents (TLD) et par chambres d'ionisation sont réalisées dans les maquettes critiques EOLE (MOX) et MINERVE (UO2). L'interprétation rigoureuse de ces mesures nécessite des développements spécifiques basés sur des simulations Monte-Carlo de transport couplé neutron-gamma et gamma-électron. Les développements effectués se singularisent notamment par la modélisation de phénomènes de cavités et d'émissions gamma retardés par décroissance des produits de fission. Les comparaisons calcul-mesure ont permis d'identifier un biais systématique C/E=0.72 confirmant une tendance des calculs à sous-estimer la mesure. Une méthode d'ajustement Bayésienne a été développée afin de ré-estimer les principales composantes de l'échauffement gamma et de transposer les résultats obtenus aux dispositifs du RJH dans des conditions de représentativité clairement définies. Cette thèse a permis de réduire significativement les incertitudes sur la détermination des échauffements gamma de 30% à 15% (2 sigma)

The objective of this thesis is to develop the modelling of the nuclear heating of the experimental devices of the future Jules Horowitz material testing reactor (RJH). The strong specific nuclear power produced (460 kW/l) induces intense photonic fluxes which cause heating and large gradients in temperature. The design studies of the experimental devices require an accurate knowledge of these gradients. A priori, we estimate that there are large uncertainties on gamma heating calculations to about 30% (2σ). They are mainly due to the lack of knowledge about gamma emission yields and spectra and secondly come from the mismodelling of the gamma response function. In order to specify this uncertainty, a set of integral dose measurements using different kinds of TLD and a micro-ionization chamber are carried out in the UO2 core of the MINERVE research reactor. The comparison between calculated and measured integral (prompt plus delayed) gamma-ray absorbed doses in TLD shows that calculation constantly underestimates the measurement with C/E = 0.72 ± 15% (k = 2) of total uncertainties. The systematic bias observed is partially attributed to a lack of gamma-ray emission data in basic nuclear data libraries used. A Bayesian method of adjustment is developed in order to re-estimate the principal components of the gamma heating and to transpose the results obtained to the devices of the RJH. This study made it possible to reduce significantly the uncertainties on the determination of the gamma heating from 30% to 15% (2σ).; L'objectif de cette thèse est de développer la modélisation des échauffements nucléaires au niveau des dispositifs expérimentaux du futur réacteur d'irradiation technologique Jules Horowitz (RJH). La forte puissance nucléaire spécifique produite (460 kW/l) induit des flux photoniques intenses qui provoquent des échauffements et des gradiants de température importants, qu'il est nécessaire de maîtriser dès la conception. Or, les calculs d'échauffement sont pénalisés par des incertitudes rédhibitoires estimées à une valeur enveloppe et majorante de 30% (2 sigma) provenant des lacunes et incertitudes des données d'émission gamma présentes dans les bibliothèques de données nucléaires de base. Le programme expérimental ADAPh vise à réduire ces incertitudes. Des mesures par détecteurs thermoluminescents (TLD) et par chambres d'ionisation sont réalisées dans les maquettes critiques EOLE (MOX) et MINERVE (UO2). L'interprétation rigoureuse de ces mesures nécessite des développements spécifiques basés sur des simulations Monte-Carlo de transport couplé neutron-gamma et gamma-électron. Les développements effectués se singularisent notamment par la modélisation de phénomènes de cavités et d'émissions gamma retardés par décroissance des produits de fission. Les comparaisons calcul-mesure ont permis d'identifier un biais systématique C/E=0.72 confirmant une tendance des calculs à sous-estimer la mesure. Une méthode d'ajustement Bayésienne a été développée afin de ré-estimer les principales composantes de l'échauffement gamma et de transposer les résultats obtenus aux dispositifs du RJH dans des conditions de représentativité clairement définies. Cette thèse a permis de réduire significativement les incertitudes sur la détermination des échauffements gamma de 30% à 15% (2 sigma)

This paper presents results from dosimetric measurements made aboard the Mir space station and the International Space Station (ISS) using the Pille portable thermoluminescent dosemeter (TLD) system. This paper includes the dosimetry mapping and automatic readout (trapped and untrapped components) results from Mir and ISS. The mean dose rate in 2001-2003 was 7 microGy h(-1). Using the hourly measuring period in automatic mode, doses from both galactic (independent of South Atlantic Anomaly--SAA) and SAA components were determined during Euromir'95 experiment. The mean total dose rate was 12.5 microGy h(-1), while the SAA contribution was 6.2 microGy h(-1). A similar measurement was performed on ISS in 2001 and in 2003. Both the manual and automatic measurements show a significant decrease in dose rate in 2001 in comparison to 1995-1997 due to the change in solar activity. For determination of the high linear energy transfer contribution from the radiation field during the ISS mapping experiment, three CR-39 plastic nuclear track detectors (PNTDs) were co-located with each TL detector. Analysis of the combined TLD and PNTD measurements showed a typical mean TLD efficiency of 84%, a dose contribution

A variety of radiation sources exist at the Department of Radiology and the Department of Nuclear Medicine at Karolinska University Hospital Huddinge. Radiation sources can also be found in areas outside of these departments due to the wide use of mobile xray machines and fluoroscopic c-arm equipment and also due to the movement of patients that have received diagnostic or therapeutic doses of radionuclides. In a proposal for a new legislation from the Swedish Radiation Protection Authority (SSI), which was later issued as legislation SSI FS 2005:6, the effective doses of the general public from a practice using ionising radiation need to be kept below stated limit of 0.1 mSv/year. This project was performed to verify the dose limit for individuals of the general public in the above mentioned practices. Long-term measurements with TL-dosimeters were utilised to carry out the environmental monitoring of the areas throughout the Departments of Radiology and Nuclear Medicine. To assess the contribution of ionising radiation from rooms housing mobile fluoroscopic c-arm equipment to surrounding areas, a tissue equivalent phantom of size (30×30×20 cm3) was employed to simulate a patient and the scattered radiation was monitored by using area monitors, such as portable proportional counters. The annual effective doses were calculated in terms of personal dose equivalent as well as ambient dose equivalent monitored using TL-dosimeters and area monitors, respectively. The stated limit of 0.1 mSv/year to the general public was verified by risk analysis. An attempt to create a method for determining the amount of radiation shielding in terms of lead equivalence in walls, doors, protective glasses of manoeuvre rooms and cupboards of diagnostic x-ray labs was also performed using a radiation point source of 99mTc and a NaI scintillation detector. Depending on the accuracy in the measurements the amount of lead deviated slightly from the expected 2 mm value based on the former legislation SSI FS 1991:1.

The main purpose of the IAEA/WHO TLD postal audit programme for dosimetry in radiotherapy is to provide independent verification of the dose delivered by treatment machines in radiotherapy centres. The results of the TLD audit are considered acceptable if the relative deviation between participant's stated dose and the TLD determined dose is within ± ; 5%. The IAEA maintains a strict internal quality control of the TLD system. The system calibration is verified at every reading session and the dose response and fading are verified regularly. There are 7 hospitals (with all together 6 60Co sources and 7 accelerators) in which radiotherapy in Croatia is performed. In 2003 and 2005 TLD audit was organized for all radiotherapy centres ; it included 6 60Co sources and 12 high-energy X-ray beams. The maximum deviation between participants' and IAEA determined doses were 5% and 4% in 2003 and 2005 respectively. The method of dose comparison and the results will be discussed in the paper in details.

Ruđer Bošković Institute (RBI) criticality dosimetry system consists of a chemical dosimetry system (developed in RBI) for measuring the total (neutron + gamma) dose, and a thermoluminescent (TL) for a separate determination of the gamma ray component. The dosimeter has been designed as a glass ampoule filled with the chlorobenzene-ethanol-trimethylpentane (CET) solution and inserted into a pen-shaped plastic holder. For dose determination, a newly constructed optoelectronic reader has been used. Doses in the range 0.2-15 Gy can be measured. The RBI teem took part in the International Intercomparison of Criticality Accident Dosimetry Systems at the SILENE Reactor, Valduc, 2002, with the CET dosimetry system and TLD-700 TL detectors. The results for total dose obtained with CET dosimeter showed very good agreement with the reference values. Although the results obtained for gamma ray dose on average were in a good agreement with the reference values, the separate determination of the gamma gay component in a mixed field is still a difficult task and needs improvement. This improvement could be achieved using radiophotoluminescence (RPL) glass dosimetry system. Results of SC-1/FGD-200 RPL dosimetry system testing at RBI are shown. Work is partly supported by Chyoda Technol Corporation

Pulmonary radiograms are essential in the diagnostics of lung diseases of children and youth. The frontal and lateral chest radiographs represent the basic radiological examination of the thorax. Plain radiographic findings together with the presumptive clinical diagnosis will determine the need for further imaging. Chest radiography represents the majority of radiological examinations. Therefore the contribution of pulmonary radiograms to the exposure of the young population is essential. For evaluation of the children exposure the measurement of the radiation dose during the radiological examination of thoracal organs is needed. The dose measurement on patients in X-ray diagnostics is not easy, because low doses with low and various energies have to be measured. The aim of this study was to compare various thermoluminescent detectors (TLD) and radiophotoluminescent (RPL) glass dosimeters for dose measurements in routine X-ray diagnostic of chest. Doses were measured with dosimeters placed on several points (depending of the type of presumed examination) of the “ baby phantom” and also with the dosimeters placed “ free-in-air” . Irradiations were performed by the Shimadzu X-ray unit and the irradiation conditions selected were that most commonly used for children examinations. The results obtained with different detectors were compared and discussed. Special attention was made to the energy dependence of various dosimeters. Various tissue equivalent LiF detectors and the RPL dosimeters showed good characteristics for the measurements in the X-ray field. The RPL dosimeters have to be applied carefully on the patient because of their size. The results were discussed in radiation protection point of view.

In order to measure a three-dimensional dose distribution in X-ray radiotherapy, we developed TL slab dosimeter with new TL phosphor Li3B7O12(Cu), which has Zeff = 7.42 and a density of 1.01 g/cm3 and synthetic resin as binder [ 1]. We can measure a three-dimensional dose distribution easily and reliably using this detector. This detector showed a promising tool for QA/QC in advanced X-ray radiotherapies such as IMRT, etc. In heavy-ion radiotherapies which shape precipitous dose distributions, it is also necessary to measure three-dimensional dose distribution easily. To use TL slab dosimeter in heavy-ion dosimetry, it is essential to measure its LET dependence sufficiently. And it is necessary to evaluate the dosimetric water equivalence of this dosimeter for heavy ions. Previous studies showed that the relative TL efficiency of this TL phosphor decreased to ~20% at the Bragg-peak of carbon 290 MeV/u beams and the stopping-power ratio of this dosimeter to water for carbon ions was 0.87 [ 2]. These results were not good for application in heavy-ion radiotherapy. It was often reported that there is a relationship between the glow curve shape of general TLDs (such as LiF and BeO) and LET. Using this relationship of glow curve and LET, the relative TL efficiency can be corrected and we could apply TLDs to dose measurement in heavy-ion radiotherapies. In this study, in order to develop better TL slab dosimeter for heavy-ion radiotherapy using TL phosphors with the above characteristics, we evaluated the dosimetric water equivalence of several base materials for TL slab dosimeter. We chose several kinds of ceramics with heating resistance as the base material; ISOPLATON E3, P1, M2, A98 S1 and Machinable Ceramics, TBS N64, N66, N1, N3 (ISOLITE Co., Ltd). We focused attention on stopping power, scattering power and nuclear cross-section of these materials for heavy ions. We calculated these interactions using the Bethe formula, the Gottschalk formula and the Sihver formula. Figure 1 shows the result of theoretical calculation of the water-equivalence ratio, stopping power ratio S/Sw, scattering power ratio T/Tw and nuclear cross-section ratio σ/σw for carbon-ion beam. In these ceramics, ISOPLANTON S1 was the best of base material for TL slab dosimeter for carbon-ion beam. On the basis of this evaluation, we will develop the TL slab dosimeter for heavy-ion radiotherapy. Fig. 1. Water-equivalence ratio of the base materials for TL slab dosimeter.

EURADOS WG-12 is performing a fesibility study to establish European trigger levels which would inform physicians about potential risk of skin injuries during interventional procedures

The purpose of this research is to examine the medical management process of placing and monitoring active duty fleet enlisted personnel in a temporary medical duty status and its impact on fleet readiness. Due to the variety of medical categories this research focuses primarily on personnel placed in Temporary Limited Duty and Medical Hold. Personnel in medical status "limbo" decrease readiness and cost the Navy millions of personnel dollars each year. The study highlights improvements in communication, education and training at all levels of the organization based on observations from the fleet and medical communities. This research is intended to provide stakeholders with a matrix for decision-making and provide guidance on the various temporary medical status categories and recommends design changes to the current Temporary Limited Duty Process. http://archive.org/details/aqualitativeexam109451050 Lieutenant, Medical Service Corps Approved for public release; distribution is unlimited.

5 pp. (2002)., Radiation damage to undulator systems made of permanent magnet materials like NdFeB or SmCo is a critical issue in SASE projects. It is of even more interest in high-duty cycle machines using superconducting accelerators such as the TESLA Test Facility (TTF), which is a prototype for the future X-FEL at TESLA. This paper reports on experience on the undulator system of the VUV-FEL of TTF-1, which ended on May 6, 2002 after nearly 3 years of operation. The radiation exposure of the undulator system was recorded continuously and meticulously over the whole installation period in the TTF linac. Results of these dosage measurements as well as magnetic measurements after de-installation are reported. A comparison with magnetic field data taken prior to installation is given.

The increasing use of artificial sources of ionising radiation causes a need for the collection of well-documented data on radiation doses in the environment. An environmental dose monitoring system must be capable of measuring a man-made contribution on the order of one tenth of the natural background under unfavourable field conditions such as sunlight, extreme temperatures, high humidity, etc. Thermoluminescence dosimeters can satisfy these requirements and therefore they play very important role in environmental monitoring. Various high sensitivity dosimeter systems based on LiF:Mg,Cu,P and Al2O3:C along with TLD-700 were investigated in laboratory and field tests. The simulated environmental tests described in ANSI Draft Standard N13.29 were applied. TLD systems were involved in intercomparisons based on different protocols.

Exposure of crew, equipment, and experiments to the ambient space radiation environment in low Earth orbit poses one of the most significant problems to long-term space habitation. Accurate dose measurement has become increasingly important during the assembly (extravehicular activity (EVA)) and operation of space stations such as on Space Station Mir. Passive integrating detector systems such as thermoluminescent dosemeters (TLDs) are commonly used for dosimetry mapping and personal dosimetry on space vehicles. The well-known advantages of passive detector systems are their independence of power supply, small dimensions, high sensitivity, good stability, wide measuring range, resistance to environmental effects, and relatively low cost. Nevertheless, they have the general disadvantage that for evaluation purposes they need a laboratory or large--in mass and power consumption--terrestrial equipment, and consequently they cannot provide time-resolved dose data during long-term space flights. KFKI Atomic Energy Research Institute (KFKI AEKI) has developed and manufactured a series of thermoluminescent dosemeter systems for measuring cosmic radiation doses in the 10 microGy to 10 Gy range, consisting of a set of bulb dosemeters and a compact, self-contained, TLD reader suitable for on-board evaluation of the dosemeters. By means of such a system, highly accurate measurements were carried out on board the Salyut-6, -7 and Mir Space Stations as well as on the Space Shuttle. A detailed description of the system is given and the comprehensive results of these measurements are summarised.

In order to determine the energy response characteristics, several types of TLDs previously calibrated with 137Cs gamma rays, were irradiated with X-ray beams in the range of effective energies between 33 and 116 keV. The following types of TLDs were investigated: two types of the recently developed highly sensitive LiF:Mg,Cu,P material: TLD-700H and GR 200A, two new types on the basis of lithium borate: Li2B4O7:Cu,In and Li2B4O7:Cu,In,Ag (developed in the Institute of Nuclear Science, Vinča), two well known types of LiF:Mg,Ti detectors: TLD-100 and TLD-700 and the new, highly sensitive Al2O3:C. Measured energy responses relative to air, normalised to 137Cs photons were compared with calculated data. Although the deviations of the measured data from the “theoretical” predictions are different for all investigated TLDs, there are no large differences in “tissue equivalency” between them. The only exception is Al2O3:C, which (due to large energy dependence) is not suitable for personal dosimetry in an unknown photon radiation field.