Safety Barriers in Offshore Drill Rigs Derived From Accident Investigation

This paper uses historic accidents to identify important barriers for the structural and marine safety of offshore drill rigs. Several accidents and near misses have been evaluated and barriers that failed, did not exist at the time of the accident or that stopped the accident are identified. Based on these analyses and review of anticipated failure modes in standards and regulations, a simplified generic barrier diagram is established. The generic barrier diagram can be used to evaluate current practice and provide input to general safety management. The possible degradation of the barriers with increasing rig age is also evaluated, and the possible effect the degradation might have on the integrity of aging rigs.