Accidents and Incidents in the Transport of Radioactive Material-An Analysis of 37 Years of Experience

The regulations for the safe transport of radioactive material (IAEA 1990)are formulated on the basis that accidents, even severe ones, can and do occur in transport. It is fundamental that safety is built into the design of the packages and that packaging should be appropriate to the potential hazard of the contents. An analysis of the radiological consequences of the accidents which have occurred provides a means of assessing the effectiveness of these regulations. Where compliance issues are raised it enables enforcing authorities to focus resources on areas of greatest concern. With this in mind, in 1983 the UK Department of Transport in conjunction with the Health and Safety Executive asked the National Radiological Protection Board to assess the radiological impact of transport accidents and incidents which had occurred over a 20- year period. The results of the study, published in 1984 (Gelder et al. 1984) were felt to be sufficiently useful for it to be revised and updated in 1990 (Shaw et al. 1990a) and for annual updates to be published thereafter (Hughes and Shaw 1990-1995 ). Some details of the database together with preliminary results were published in 1990 (Shaw et al. 1990b). A further revision and consolidation, using a different system of classification, took place in 1995 covering the period 1958 to 1994 and is described below. The database on which transport events are registered has developed and changed over time. The information recorded, and the number of ways in which it can be analysed, has improved. The method of classification of events has evolved to reflect the experience gained of the types of event which reoccur. Both the computer software and hardware have been progressively improved following the rapid changes in these areas over the last decade. The number of events recorded has risen from around 300 over 20 years in 1984 to more than 500 for the 3 7 years at present . The time period covered by the database has been extended as new events happened and earlier, overlooked, events came to light.