Bow-tie analysis of a fatal underground coal mine collision

Background: Bow-tie analysis combines aspects of fault-tree analysis and event-tree analysis to identify an initiating event; its causes and consequences; and potential preventive and mitigating control measures or barriers. Aims: The aim of the research is to analyse a fatality which occurred in a Queensland underground coal mine in 2007 to illustrate this technique. Method: The case study concerns a fatality which occurred at an underground coal mine in Queensland in 2007. Results: A continuous mining machine operator was crushed against the mine wall by a shuttle car following a loss of situation awareness by the shuttle car driver. The causes included the use of shuttle cars in close proximity to pedestrians, and driver inexperience. A directional control-response incompatibility contributed to the severity of the final consequence. A range of potential control measures are identified including: (i) replacing shuttle cars with a mobile conveyer; (ii) non-line-of-sight remote control of continuous miners; (iii) proximity detection interlocked with shuttle car controls; (iv) “always-compatible” shuttle car steering design. Conclusions: Proximity detection sensors interlocked with shuttle car control systems is a technically feasible control measure which should be implemented at all underground coal mines. Non-line-of-sight remote control of continuous mining machines or automation of continuous mining machines would remove operators from this hazard entirely. A bow-tie representation provides an effective way of systematically examining the causes, consequences, and potential preventive and mitigating control measures or barriers associated with a previous incident.