Posted By Robin V Boughton Paul, From my understanding of the Dangerous Occurence definitions in RIDDOR 1995 and your discription of the incident I do not think that it is a repotable occurence. The failure of two protection/switchgear systems certainly gives cause for concern but the outcome does'nt meet the criteria in the regulations ie (iv) Any incident where plant contacts or causes an electrical discharge of 200 volts or more, from overhead electrical lines, unless in either case it was intentional. (v) Electrical short circuit or overload followed by fire or explosion which results in the stoppage of the plant involved for more than 24 hours or which has the potential to cause the death of any person. Regards, Robin