Établi dans le cadre du groupe de travail COFREND-SFRP, cet atelier avait pour principal objectif de recenser le retour d'expérience des incidents existant dans le domaine de la gammagraphie industrielle et, si possible, de l'améliorer. Les produits issus de l'atelier sont principalement destinés à enrichir le contenu des formations des opérateurs et des personnes compétentes en radioprotection des entreprises de gammagraphie industrielle. Différentes sources bibliographiques dans lesquelles des incidents/accidents sont recensés ont été analysées : les bases de données IRID et RELIR ont été particulièrement étudiées. Il a alors été identifié que le retour d'expérience existant n'était pas totalement représentatif des événements rencontrés en France aujourd'hui. De nouveaux types d'incidents (non maîtrise de la zone balisée, blocage du porte-source dans la gaine dû à la présence de corps étranger...) ont été identifiés à partir desquels de nouvelles fiches RELIR ont été établies. En parallèle, une synthèse des leçons issues des incidents recensés au cours de l'atelier a été élaborée.

Since the beginning of the 90s, EDF has made great efforts to improve ALARA for occupational exposures in the French nuclear power plants. This resulted in the important reduction of the individual doses (581 workers received more than 20 mSv in 1996; in 2006 no one received more than 20 mSv and only 17 received more than 16 mSv) and of the average collective dose per reactor (reduction by more than a factor two in ten years). EDF wishes to continue its efforts. One of the ways of improvement is the analysis of the feedback experience in the foreign power plants having good dosimetric results or with a recent significant improvement of the dosimetric results. Thus, between 2003 and 2006, the CEPN has organized for EDF eight benchmarking visits on the organisation and practical implementation of radiation protection in foreign nuclear power plants. For each visit, a team composed of two representatives from EDF and two representatives from CEPN, goes to the site during a week and meets representatives of services implied in the implementation of the specific topic, which was selected. Several good practices of radiation protection were identified during these visits: the good integration of radiation protection in the management of the plant; the efforts in reducing the source term; the fundamental impact of the reduction of exposed volumes of work through the optimisation of the maintenance programmes and modification of the design reducing the necessity of maintenance; a close and experienced radiological protection; new tools in the service of radiological protection for the 21st century, in particular the use of remote monitoring systems.

In the beginning of the 1980ies, the problem of outside workers’ radiation protection within the nuclear facilities was raised. Those workers received 80 % (and even more) of the collective dose from most nuclear facilities and most of the time higher individual doses than the workers of the nuclear operators. Outside workers’ radiation protection issue was not explicitly taken into account into the 1980 Basic Safety Standards. Regarding that situation, the EC issued the Directive 90/641/Euratom in order to ensure that outside workers would benefit from the same level of protection as permanently employed workers, and which has led to an improvement of outside workers’ radiation protection. The evolution of the context during the latest years – implementation of new Basic Safety Standards, enlargement of the EU as well as the increase of dismantling and waste handling activities – has lead the EC DGTREN to investigate the possibility to review and improve the Directive 90/641/Euratom. The EC DGTREN awarded the CEPN with a contract in order to evaluate through a survey the level of implementation of Directive 90/641/Euratom into the EU national regulations as well as its operational implementation. In addition, a Seminar was held at the Luxembourg EC facilities on 29 and 30 November 2005, gathering EC representatives, national regulatory bodies representatives, operators, outside undertakings and trade union representatives in order to discuss this topic. Sixteen Member States were represented, among which five New Member States. It has then been a first opportunity for DGTREN representatives to discuss outside workers topics with new Member States representatives since they joined the Union. The survey carried out by the CEPN, as well as the different presentations, have demonstrated the existence of differences in national approaches to the practical implementation of the Directive 90/641/Euratom, while aiming to the same fundamental objective: ensuring that outside workers benefit from the same level of protection as permanently employed workers. It appears also that the Directive 90/641/Euratom is, in most of the EU countries, totally implemented into national regulations in spite of what appears as inconsistencies between some definitions provided by the Directive 90/641/ Euratom and the Basic Safety Standards. Definitions as well as sharing of responsibilities are therefore not understood in the same way from one country to another. The participants thus welcome the initiative of the Commission to integrate outside workers’ radiation protection Directive into the future Basic Safety Standards, as well as its wish to consult end users. It is also expected to maintain, in the following years, the coherence between the new Basic Safety Standards and other European legislation (for example, directives related to risk at work or directive on free movement of services).

The theme of the workshop was the control of exposures received by workers from natural radiation sources. Specifically, workplace exposures from NORM (i. e. industrial materials such as ores and scales containing Naturally Occurring Radioactive Material) and from radon were considered. For completeness, occupational exposures (to aircrew) from cosmic rays were also described, but were not within the main scope of the workshop. The objectives of the Workshop were to consider the following questions: • how can the commitment to radiation protection be encouraged and increased?; and • how should exposure management (for NORM and radon in the workplace) be improved?

An efficient but little known tool for the application of the ALARA principle: ISOE (Information System on Occupational Exposure). The Information System on Occupational Exposure to ionizing radiation (ISOE) is a program launched by the Nuclear Energy Agency (NEA) in 1992. It was developed to address the needs of nuclear power plants and safety authorities as a comparison and information tool on practices in terms of optimization (ALARA principle), in NEA member countries. To date, more than 90% of the operating nuclear power plants in the world are participating in this program, which is organized in a decentralized form, with a steering group and four technical centers (Europe, Asia, north America and IAEA). The ISOE program includes an occupational exposure database and an information exchange and communication network. The databases permit the preparation of studies and comparisons of practices, either in a factual or analytical way. Thus, the ISOE program favors exchanges to the benefit of all participants and helps to bring operational radiation protection ever closer towards the "achievable" of ALARA.

Implementation of the principle of optimization (ALARA), an essential radiation protection regulations, remains very limited in the medical field, even though 80% of workers whose exposure exceeds 50 mSv are to be found in this domain. The doses measured by legal dosimetry sometimes underestimate the real exposure of workers. It is therefore necessary to optimize the protection of occupational exposure in the medical field. This paper reviews the steps of the optimization procedure with emphasis on specificity of its application in this domain. Operational dosimetry as well as information on the residual risk due to low exposures and a better estimation of the risk/benefit factor for the patient are needed for satisfactory implementation.

Implementation of the principle of optimization (ALARA), an essential radiation protection regulations, remains very limited in the medical field, even though 80% of workers whose exposure exceeds 50 mSv are to be found in this domain. The doses measured by legal dosimetry sometimes underestimate the real exposure of workers. It is therefore necessary to optimize the protection of occupational exposure in the medical field. This paper reviews the steps of the optimization procedure with emphasis on specificity of its application in this domain. Operational dosimetry as well as information on the residual risk due to low exposures and a better estimation on the risk/benefit factor for the patient are needed for satisfactory implementation.

Tritium in the aquatic environment and the associated risk. Tritium, which is naturaily present in the environment under tritiated water form, participates to the global water cycle. Today, nuclear fuel cycle facilities represent the main source of man-made tritium. The civilian production is estimated to he about 2x104 TBq/y, corresponding to a third of the natural production. Due to the fact that tritium releases are very local, concentrations in water higher than natural background (of 0.1 to 0.9 Bqil for surface waters) are observed around these sites. Measurements in French aquatic environment reveal tritium concentration generally helow 10 Bqil for underground waters and below 20 Bqil for rivers. Nevertheless, some ground waters and some rivers presents localiy a concentration up to a few hundreds of Bqil. Moreover, measurements performed in France are geaerally coherent with monitoring in other European countries. Furthermore, the associated radiological impact for a potential individual taking aii his water needs from a 100 Bqil tritiated water source, was evaluated to about one thousandth of the natural background.