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Purpose: To avoid complications in total body irradiation (TBI), it is important to achieve a homogeneous dose distribution throughout the body and to deliver a correct dose to the lung which is an organ at risk. The purpose of this work was to validate the TBI dose protocol and to check the accuracy of the 3D dose calculations of the treatment planning system. Methods: Dosimetry based on alanine/electron paramagnetic resonance (EPR) was used to measure dose at numerous locations within an anthropomorphic phantom (Alderson®) that was irradiated in a clinical TBI beam setup. The alanine EPR dosimetry system was calibrated against water calorimetry in a Co-60 beam and the absorbed dose was determined by the use of “dose-normalized amplitudes”math formula. The dose rate of the TBI beam was checked against a Farmer ionization chamber. The phantom measurements were compared to 3D dose calculations from a treatment planning system (Pinnacle®) modeled for standard dose calculations. Results: Alanine dosimetry allowed accurate measurements which were in accordance with ionization chamber measurements. The combined relative standard measurement uncertainty in the Alderson phantom wasmath formula. The humanoid phantom was irradiated to a reference dose of 10 Gy, limiting the lung dose to 7.5 Gy. The ratio of the average measured dose midplane in the craniocaudal direction to the reference dose was 1.001 with a spread of ±4.7% (1 sd). Dose to the lung was measured in 26 locations and found, in average, 1.8% lower than expected. Lung dose was homogeneous in the ventral-dorsal direction but a dose gradient of math formula was observed in the craniocaudal direction midline within the lung lobe. 3D dose calculations (Pinnacle®) were found, in average, 2% lower compared to dose measurements on the body axis and 3% lower for the lungs. Conclusions: The alanine/EPR dosimetry system allowed accurate dose measurements which enabled the authors to validate their TBI dose protocol. Dose calculations based on a collapsedcone convolution dose algorithm modeled for regular treatments are accurate within 3% and can further be improved when the algorithm is modeled for TBI.

[EN] While the founding members of CHERNE gradually retire, the memory of the early steps of the network should not be lost. CHERNE (`Cooperation for Higher Education on Radiological and Nuclear Engineering¿) is the product of a specific Erasmus activity possible in the early 2000s: the intensive programmes (IP). The first step was a collaboration of three partners (Czech Technical University CTU, Institut Supérieur Industriel de Bruxelles ISIB, Universitat Politècnica de València UPV) organising in 2002 the 3-year IP `PAN: Practical Approach to Nuclear techniques¿, soon integrating two other partners (Aachen University of Applied Science AcUAS, XIOS Hogeschool Limburg). A second IP `SPERANSA: Stimulating Practical Expertise in RAdiation and Nuclear SAfety¿ was first organised without Erasmus support in 2005. A workshop was held in 2005 at UPV, including colleagues from other universities. Its main goal was to put in contact professors and researchers from European Institutions in order to share experiences in education and research in Radiation Protection and Nuclear Engineering. The creation of an informal group of universities to develop activities for the benefit of students was discussed. With the addition of Università degli Studi di Bologna (UniBo) to the initial group, the CHERNE network was created. It attracted rapidly more members (6 adhesions in 2006). CHERNE was conceived as a non-formal wide-scope open network, easily integrating new members, offering affordable activities to the students and mostly relying on Erasmus subsidies. The main goal was still the organisation of Erasmus IP¿s based on practical activities, benefitting of the access to big experimental facilities offered by several partners, like reactors, accelerators, or a radiochemical laboratory. SPERANSA was organised from 2006 to 2008, `JUNCSS: JÜlich Nuclear Chemistry Summer School¿ from 2007 to 2011 and `RAPIX-NOCOS: Radiation protection in non-conventional sectors¿ in 2007 and 2008 without Erasmus support. The annual workshops triggered exchanges between partners and attracted more institutions. The first workshops saw intense discussions about the network organisation and the types of activities that could be organised. A kind of maturity was reached from 2008.

De CGR-MeV cyclotron in Fleurus werd gebruikt van 1983 tot 1993 voor de productie van medische radionucliden en is nu, na meer dan 20 jaar buiten gebruik, klaar om ontmanteld te worden. Door het gebruik zijn de materialen van de versneller geactiveerd. De focus van deze studie is de radiologische karakterisatie van de interne en externe metallische componenten in de versnellersruimte. Het resultaat ervan zal meer inzicht geven in de verschillende opties voor de behandeling van de geactiveerde metalen. Deze opties zijn gebaseerd op de Belgische niveaus voor onvoorwaardelijke vrijgave en de acceptatiecriteria van gespecialiseerde smelterijen. Op basis van dosistempo metingen bij verscheidene metallische componenten werden er 82 stalen geboord. Naast deze 82 stalen, werden er nog 3 stalen genomen uit de betonnen muren als een eerste indicatie van de activatie ervan. De stalen bestaan uit ongeveer 1 gram metaal of beton en werden allen gemeten in dezelfde geometrie. Ten slotte werden de 85 stalen gekarakteriseerd door gamma spectrometrie met behulp van een HPGe detector. In de metallische stalen was Co-60 het enige te identificeren radionuclide met een specifieke activiteit variërend tussen niet-detecteerbaar en 328 kBq/kg. De deflector, de bundeluitgang en de interne trefschijf omgeving werden geïdentificeerd als de meest geactiveerde delen. Op basis van de specifieke activiteiten is 11% van de stalen geschikt voor onvoorwaardelijke vrijgave. De hoger geactiveerde materialen zijn bedoeld voor gespecialiseerde smelterije