Rollover, diesel ignition and a crane failure
Three reported safety incidents on coal mines prompting safety warnings this month
In one incident reported this month, a gantry crane hook and heavy hoist rope crashed to the ground after detaching from the winding drum, narrowly averting a potential tragedy.
The incident occurred while a worker was “lowering the crane hook” to prepare for attaching a load. As the hook block reached its lowest point, the entire assembly suddenly fell. An immediate investigation revealed critical failings in maintenance and inspection procedures as the root cause, with a “damaged and inoperable hook height limit switch” identified as the primary mechanical failure.
“The absence of an operational limit switch allowed the crane hook to lower far further than it should have, resulting in all of the rope unwinding off the drum,” an investigator said.
The investigation concluded that the incident was entirely preventable and recommended a “robust system for regular maintenance, inspection, and testing”
In a second incident, an ignition event occurred near the fuel tank cap area of a diesel bulldozer.
While liquid diesel is generally not highly flammable at room temperature,
these vapours can become flammable when mixed with air in the correct concentration and exposed to an ignition source (such as a spark or flame). This risk is particularly high in enclosed areas or at elevated temperatures.
Following an investigation, the safety regulator recommended that coal mine workers be made aware of this specific incident and the high risk of serious injury or fatality associated with it. They also recommended that miners get updated training on managing flammable liquids.
In the final incident reported this month, a bulldozer overturned during the construction of a haul road after reversing too close to an open edge. Fortunately, the operator, who was wearing a seatbelt, was not hurt.
During the reverse manoeuvre, the dozer’s left track dropped over the open edge, and this sudden drop caused the right track to lift, initiating a slow roll that resulted in the dozer landing on its side.
The investigation determined that the cause was the operator’s failure to identify the open edge of the work area while reversing. In a penetrating insight, the safety regulator recommended “constant vigilance” and positively identifying the location of all open edges, drops, or berms, especially when reversing or maneuvering near elevation changes.
They also recommended the proper use of spotters or advanced camera/sensing technology when visibility is compromised.
