Underground » Health and Safety
Since 1990 BHP Billiton - Illawarra Coal has been actively researching a number of issues associated with the use of diesel equipment in underground coal mines. From this research it is clear that both the USA and South Africa have a different approach to New South Wales in the use of diesel equipment underground. In NSW only flameproof vehicles are permitted whereas flame protected vehicles are common at US and South African mines. Similarly, in recent years Queensland has embarked on an extensive research programme of flame protected vehicles.
Given the above, it was considered that the reasons for this disparity should be investigated and if appropriate a suitable flame protected 4WD vehicle should be developed and trialled under NSW operating conditions. Following initial investigations within Australia and overseas it was decided to develop a vehicle in accordance with the draft Australian Standard AS3584.1 "Diesel Engine Systems for Underground Coal Mines - Part 1: Fire Protected" and the NSW Department of Mineral Resources document MDG1 "Guideline for Free Steered Vehicles".
Over a period of several years a Toyota Landcruiser 4WD vehicle was modified and then altered as the draft standard changed, resulting in significant delays in the development of a trial vehicle. Nevertheless the vehicle commenced trials at Elouera Colliery on 4 February 2003 with encouraging results.
In initial trials all systems performed within design expectations, with a number of occupational health and safety benefits being clearly evident in comparison tests to current flameproof vehicles. For example noise and vibration levels were significantly reduced, both within the driver's cabin and the main passenger area. Similarly, the 4WD had significantly lower raw exhaust particulate levels (approximately 80%) which translated into ambient concentrations within the driver's cabin of the 4WD of 19 g/m3 elemental carbon compared to 121 g/m3 within comparison flameproof vehicles.
One significant development of the project has been the incorporation of dual methanometers within the vehicle shutdown system. This provides an added level of operational safety and ensures that the vehicle ceases operation if the ambient methane level within transportation roads exceeds agreed levels.
While the project has been long and frustrating, the initial trials have indicated that major benefits to the coal industry and employees potentially exist if such vehicles were to be introduced into the NSW coal industry. To explore factors such as operational effectiveness and long term maintenance cost, BHP Billiton - Illawarra Coal has decided to continue with further long term trials of the vehicle at the Dendrobium Mine.