ITER breeding blanket safety analysis

Safety analyses have been performed for the reference ITER breeding blanket, to quantify the consequences of loss of coolant accidents. It has been shown that as long as the blanket module integrity is preserved, the hydrogen generation due to the chemical reaction of beryllium with water/steam is well below the ITER design limit. Parametric studies, however, assuming failure of the safety shutdown system, break of the box and higher local beryllium pebble temperatures show that for this type of accident outside the design basis considerable hydrogen generation can not be excluded, if the beryllium and steam temperatures exceed certain limits. (authors)