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[en] The article describes the key activities of the Institute for Communication, General Services and Administration (CSA) of the Belgian Nuclear Research Centre SCK-CEN. CSA deals with communication and knowledge management and co-ordinates courses on the fundamentals and applications of nuclear research. CSA also comprises the administrative, financial, logistic and central technical services, as well as human resources and ICT
[en] The article refers to an abstract of a doctoral thesis. From a legal perspective there exists a clear need for a general framework describing conditions and consequences of risk management in the field of high technology. Despite the existence of many kinds of Safety Procedures and Soft Law, specific guidelines are lacking for regulators and courts, especially in case of scientific controversy and uncertainty about the health effects of an activity or a product such as low doses of ionising radiation, electro-magnetic fields, genetically modified organisms, PCB's in salmon etc. The research of the PISA Project on Legal Aspects and Liability has been focussed on the medical applications of ionising radiation. The safety approach depends on the risk characterisation and differs for stochastic and deterministic effects. The most important objective was to find liability or funding systems which can cope with these differences, in particular between dose limits (as for the nuclear industry), reference dose levels foreseen in the EC medical Directive (as for nuclear medicine), and Optimisation referring to the ALARA principle. Risk assessment and risk management that are based on traditional narrow risk-assessment models have to be revised in the light of the Precautionary Principle. This principle urges policy-makers to adopt a broader, more pluralistic approach, considering the societal equilibrium, i.e. the general interest of the activity at stake, the general impact of individual protective measures and the existence of reasonable alternatives from a sociological, economical, scientific and technological point of view. One of the characteristics of the Precautionary Principle relates to our opinion to the collective damage to human health, i.e. a detriment that relates to a group of people. Nevertheless, as a result of the application of the Precautionary Principle, we believe that in case of individual damage the standard of care shall be more and more defined, following the risk characterisation and assessment which has to be introduced once a scientific or societal problem occurs with regard to medical practices, already subject to the legal duty of Justification and of Informed Consent. For some specific cases, as paediatric CT doses, the 2003 report of the Belgian Health Council gives a clear warning and refers to collective doses that are significantly higher than in the neighbouring countries. It cannot be denied that such a repeated warning urges decision makers and hospitals to take corrective actions, in particular when poor optimisation is put in place. Causality in the nuclear field is another complex problem, where worldwide alternatives are under consideration, such as probability of causation. However, such a concept, based on statistical proof, can hardly be implemented in Belgian law since our tort- and insurance-system is based on the individual relationship between liable actor and victim
[en] Prolonged exposure to space radiation and extended microgravity has revealed profound physiological and clinical changes in astronauts. The health problems thought to be related to the effects of microgravity include a decrease in the heart and the respiratory rates, a loss of body weight, changes in bone calcium, a redistribution of body fluids with a greater amount in the upper body, a decrease in muscle tissue, a weakening of the veins and arteries in the legs, as well as an underproduction of red blood cells leading to anaemia. At the cellular and molecular levels, microgravity is known to induce both a loss of T-cell activation and changes in gene expression patterns, as well as a three-dimensional growth of normal cells and tumour cells, an alteration of the mitochondrial organization, a modification of the production of extracellular matrix proteins and apoptosis in some types of cells. The Earth's magnetic field protects us from harmful radiation. On Earth, we are still exposed to small amounts of radiation when we go for medical x-rays, when we travel on transcontinental flights or just from radon in the air. However, astronauts are exposed to 50 to 100 times as much radiation - and that is just in a low Earth orbit. In deep space, astronauts can be exposed to even higher doses. It is well known that large amounts of radiation can cause severe health effects by altering DNA in our cells. The health effects from space radiation are therefore a critical safety concern for long-term space travel. Possible health risks include cancer, cataracts, acute radiation sickness, hereditary effects, and damage to the central nervous system. The aims of this research are 1) to ensure the immunological monitoring of a cohort of astronauts (having spent around 6 months aboard the International Space Station ISS) and 2) to investigate the effects of an in vitro exposure of endothelial cells and other types of cells to radiation and/or microgravity conditions
[en] Implementation of remedial actions after a radiological contamination of the environment has to take into account, alongside with radiological and feasibility criteria, also the acceptability of the countermeasures, ethical and environmental considerations, as well as the spatial variation and the needs of people in urban, rural and industrial environments. This highlights multi-criteria analysis as a suitable tool, since it is able to structure discussions and to facilitate a common understanding of the decision problem, with the values and priorities of the actors involved. The related theoretical framework, multi-criteria decision aid (MCDA), has emerged from the operational research field as an answer given to a couple of important questions encountered in complex decision problems. Firstly, the aim is not to replace the decision maker with a mathematical model, but to support him to construct his solution by describing and evaluating his options. Secondly, instead of using a unique criterion capturing all aspects of the problem, in MCDA one seeks to build multiple criteria, representing several points of view. The methods belonging to MCDA can be classified as multi-attribute utility/value methods, outranking methods and interactive methods. Past attempts to apply multi-criteria analysis in the context of nuclear emergency management have highlighted however the need to better integrate the operational and socio-political context of the decision-making process into the tools and models developed for decision-support. This PhD project had two main objectives: 1) to develop a multi-criteria decision aid model for the decision problem on countermeasures for contaminated milk, that better accommodates the nuclear crisis management context in Belgium and 2) to build prototype tools implementing and demonstrating the methodology developed
[en] At the SCK-CEN different specialised services are delivered for a whole range of external and internal customers in the radiation protection area. For the expertise group of radiation protection dosimetry and calibrations, these services are organized in four different laboratories: dosimetry, anthropogammametry, nuclear calibrations and non-nuclear calibrations. The services are given by a dedicated technical staff who has experience in the handling of routine and specialised cases. The scientific research that is performed by the expertise group makes sure that state-of-the-art techniques are being used, and that constant improvements and developments are implemented. Quality Assurance is an important aspect for the different services, and accreditation according national and international standards is achieved for all laboratories
[en] The protection of medical personnel in interventional radiology is an important issue of radiological protection. The irradiation of the worker is largely non-uniform, and a large part of his body is shielded by a lead apron. The estimation of effective dose (E) under these conditions is difficult and several approaches are used to estimate effective dose involving such a protective apron. This study presents a summary from an extensive series of simulations to determine scatter-dose distribution around the patient and staff effective dose from personal dosimeter readings. The influence of different parameters (like beam energy and size, patient size, irradiated region, worker position and orientation) on the staff doses has been determined. Published algorithms that combine readings of an unshielded and a shielded dosimeter to estimate effective dose have been applied and a new algorithm, that gives more accurate dose estimates for a wide range of situations was proposed. A computational approach was used to determine the dose distribution in the worker's body. The radiation transport and energy deposition was simulated using the MCNP4B code. The human bodies of the patient and radiologist were generated with the Body Builder anthropomorphic model-generating tool. The radiologist is protected with a lead apron (0.5 mm lead equivalent in the front and 0.25 mm lead equivalent in the back and sides) and a thyroid collar (0.35 mm lead equivalent). The lower-arms of the worker were folded to simulate the arms position during clinical examinations. This realistic situation of the folded arms affects the effective dose to the worker. Depending on the worker position and orientation (and of course the beam energy), the difference can go up to 25 percent. A total of 12 Hp(10) dosimeters were positioned above and under the lead apron at the neck, chest and waist levels. Extra dosimeters for the skin dose were positioned at the forehead, the forearms and the front surface of the upper legs
[en] The Learning Centre at the Belgian Nuclear Research Centre SCK-CEN develops competencies of its staff, doctoral students, temporary workers and external employees. For this purpose, the Learning Centre organises a range of training courses specifically aimed at the expectations and needs of various target groups. The article contains an overview of activities of the SCK-CEN Academy.
[en] The The mission of the Learning Centre at the Belgian Nuclear researcxh Center SCK-CEN is to develop the competences of its own members of staff, doctoral students, temporary workers and external employees. For this purpose, the Learning Centre organises a range of training courses specifically aimed at the expectations and needs of various target groups.