Radiological incidents in industrial gammagraphy. Analysis of 20 French cases and lessons learned

Since nearly half a century, the Radiopathology Unit of the Curie Institute in France, has been involved in the medical treatment of nearly 600 incidentally irradiated persons in France. For medical purpose, this Institute has created a data base containing information on the causes of the incidents, the level of individual exposures, the health consequences and the medical treatment. Recently, this data base appeared to be also of great interest in a radiation protection purpose, with the aim of preventing such incidents by a dissemination of the lessons which could be learned from the feedback analysis of the incidents. In order to test the feasibility of using this data base for radiation protection analysis, the CEPN, in collaboration with the Curie Institute, has selected the incidents which occurred in the industrial gammagraphy field in France between 1978 and 1998 (20 cases available in the Institute data base). For each case, the following information have been gathered: - circumstances and causes of the incidents - level of exposures - health consequences - nature and activity of sources - type of gammagraph equipment - qualification of workers - description of intervention planned in case of incident - participation of radiation protection staff - actions undertaken by the employer after the incident. The analysis of these incidents revealed that in most cases the consequences in terms of effective dose were rather low (from 10-1 to 10 mSv). However, in a few cases, the effective dose reached more than 100 mSv. In three cases, very high local skin irradiation occurred (hand or leg), and had severe health effects. Six main factors where identified as causes of the incidents: - the technical failure of equipment - the inappropriate behaviour of the workers after the identification of a technical incident - human error without technical failure - non-respect of regulation or safety rules - inadequate maintenance of equipment - lack of education/training in the use of gammagraphe. For most of the studied cases several factors interact during the course of the incident. The lessons which can be drawn from these analysis are of two main natures: - Technical, by an improvement of the equipment's reliability as well as of maintenance programs - Human, by the development of radiation protection education, not only for the workers, but also for the managers, favouring they awareness of radiation risk and the respect of safety rules. (author)