Blee was crushed between a shuttle car and the rib at a bord and pillar section of Moranbah North. The inquest covered lighting, shuttle car design, removal of personnel from the mining area, personal safety equipment and place change mining.
University of Queensland associate professor Robin Burgess-Limerick, whose research project Reducing Injury Risks Associated with Underground Equipment won an Australian Coal Association Research Program award in 2007, discussed the issue of potential lighting changes at the inquest.
He did not think that visibility contributed to the incident but said area lighting would have made the shuttle car’s wheel position more apparent to Blee and the cablehand as it was being loaded.
Problems around increased lighting on vehicles include maintenance difficulties and lights being broken underground.
Joy vice-president and managing director Brad Neilsen stated that side lighting for the shuttle cars was available on request and that 40-50, or roughly half, of the machines put into the market over the last two years contained more lighting than standard stock.
But he also said there were concerns that too much lighting around the car could affect the sight of people situated around the vehicle.
On shuttle car design, Burgess-Limerick said he felt the best design control would be a proximity detection system which was interlocked with the braking system.
But given that such systems are still being developed for Australian underground coal conditions, he preferred the removal of people from the area as a safety option.
Commenting on the development of an ergopod shuttle car, where both the steering wheel and seat can rotate depending on the direction of travel, Burgess-Limerick considered the vehicle a possible solution to some of the issues raised at the inquest.
But testing of the ergopod has revealed challenges related to operator training.
Joy is investigating improvements to the suspension in its shuttle cars while the OEM’s attempt to introduce stick steering, or Tiller steering, from the US did not have an overly positive reception in Australia.
Blee was working for Walter Mining at the time of the incident. The contractor company hired Arthur Chaseling, who holds a Master of Engineering, to perform an expert evaluation.
Chaseling suggested a steering valve to address steering issues with the shuttle car.
He said a sensor could be set up on the seat that would activate the valve when the operator moved into the other seat, switching the steering polarity.
He said it would be a fairly standard job and existing shuttle cars could be retrofitted.
Neilsen viewed this as a major change which would require significant assessment and testing.
He considered a 6-12 month timeframe would be realistic to look into it if appropriate approvals were granted.
The use of video camera systems on shuttle cars was touched on, but as they are affected by coal dust, reliability and maintenance difficulties, they remain in development stages.
Joy has been developing two cab designs for shuttle cars, one being a north/south facing cab with two seats and the other being an east/west cab with a single swivel seat.
The OEM is also looking at many alternative cab designs and a completely different way to control the vehicle.
On removing personnel from continuous miner areas, Neilsen said autonomous mining was realistically five to eight years into the future with significant technological hurdles to be overcome.
Considering the weight of Blee’s self-rescuer and its battery, Burgess-Limerick thought that both could be made smaller for improving safety, although this would affect how long they could be used.
Blee was performing place change mining at the time of the incident, and Queensland chief inspector of coal mines Gavin Taylor stated the US had long been recognised as the experts in close change mining.
He saw a need to look into the total system of place change operations in Australia.
Taylor said a way of ensuring best practice would be to establish a standard under legislation indicating the minimum requirements for that system of mining in the state.