Prof. Robin Burgess-Limerick – Professor of Human Factors, Minerals Industry Safety and Health Centre, The University of Queensland
ABSTRACT
Proximity advisory systems have potential to reduce collision risks associated with surface mining haul-trucks by assisting truck drivers to maintain situation awareness. The design of the visual interface by which information is provided is likely to influence the effectiveness of such systems. During ACARP project C24028, a range of information sources were reviewed including best practice guidelines from other industries. The consequences of different visual interfaces were examined when drivers were presented with potential collision scenarios via a modified haul-truck simulator (Figure 1). Additional information available in a Schematic proximity advisory visual interface was utilised by drivers to reduce collision risk and braking force and decrease travel time; although the effects were smaller in a subsequent experiment involving a smaller number of experienced truck drivers.
Design guidelines have been developed for haul-truck proximity advisory systems. Further work is underway in project C27005 in which a similar experimental paradigm is utilized to examine two of the issues identified as requiring further investigation: the relative benefits of proximity information based on distance only vs collision prediction information; and secondly, the relative benefits of auditory tones vs speech.
Mines routinely monitor the gas profiles in their goafs and roadways to determine the current status of the mine as part of their principle hazard management plan for spontaneous combustion. Many mines typically monitor for hydrogen, oxygen, methane, carbon monoxide, carbon dioxide, ethane and ethylene using micro gas chromatographs.
This paper investigates the existence of other gases which may have the potential to be used to monitor the underground environment for early signs of a heating or developing spontaneous combustion event. Simtars collected goaf and roadway gas samples into Tedlar bags to determine the “normal” background levels of these gases.
The gases analysed for included aliphatic hydrocarbons to C10, Benzene, Toluene, Ethyl Benzene and Xylene (BTEX) and aldehyde compounds. In addition to classical analytical techniques such as Gas Chromatography / Mass Spectroscopy (GC/MS) and High Pressure Liquid Chromatography (HPLC), a new micro gas chromatograph configuration previously developed by Simtars was used to conduct the analysis for aliphatic hydrocarbons to C6 and BTEX.
This paper provides a summary of the extended aliphatic hydrocarbon, BTEX and aldehyde gas profiles found in the longwall goafs and roadways of the surveyed Queensland and New South Wales mines.
Nick Coplin – General Manager, Engineering Services, Orbital Australia Pty Ltd
ABSTRACT
Australian Coal Association Research Program (ACARP) project C25073 was proposed by industry stakeholders seeking a solution that would both improve underground air quality and reduce the operational costs associated with currently implemented disposable filter technology used to control diesel particulate emissions in the underground coal mining environment. The follow-on C26070 project sought to industrialise the proof-of-concept (PoC) wall-flow diesel particulate filter (DPF) system to comply with relevant safety and health standards.
The technology has demonstrated significant DPM emissions reduction, comparable to the incumbent disposable technology, and has demonstrated the ability to meet NSW MDG43 requirements for year 2020. Testing noted that whilst the technology increased modal NO2 formation, it was compliant over typical operational duty cycles.
One of the key benefits with the use of a wall-flow DPF system is its tamper-proof design, mitigating the risk of operating unfiltered diesel plant in poorly ventilated areas. Elimination of the need for continual replacement of disposable filters provides significant operational savings estimated to be up to 80% of the incumbent technology.
The robustness of the aftertreatment solution can be maintained with both appropriate design and the use of embedded real-time, and near-real-time, electronic monitoring technology.
One of the major hazards in an underground coal mine is the interaction between mining equipment and humans. This is the result of limited vision around underground equipment and the confined space within which the equipment operates. To address this hazard, various proximity detection systems have been developed.
This paper describes a project that evaluated three proximity detection systems in an underground coal mine. The systems were subjected to a suite of nine scenarios, involving interaction between humans and continuous miners, shuttle cars and LHDs. In addition, the detection zones of the different proximity detection systems, were determined on surface as well as underground. The underground zones were determined under “normal conditions” (reference pattern), in the vicinity of an underground substation, tags at different heights, and multiple tags in zones.
The scenario results provide a documented comparison of the proximity detection systems performance when subjected to the same scenarios. This will allow a mine to make an informed selection of the most suitable proximity detection system. The detection zone results provide a graphical comparison between the performance of a proximity detection system on surface and underground. The results also present the comparison for “normal conditions” of the proximity detection system and when subjected to EMF radiation, multiple tags and tags at different heights.
The project also identified the need to develop a universal specification for a proximity detection system.
Fritz Djukic – Inspector of Mines (Occupational Hygiene), Department of Natural Resources, Mines & Energy
ABSTRACT
In May 2015 the first confirmed case of mine dust lung disease (MDLD) in the Queensland Coal industry in over 30 years was reported to the mines inspectorate. A number of cases followed that typically related to underground coal mine workers with extensive exposure history in Queensland, interstate and abroad. In October 2016 the first surface coal mine worker was confirmed with MDLD proving this hazard was not isolated to underground mines. The reidentification of MDLD in Queensland prompted several extensive reviews of the health surveillance system and the respirable dust regulations. This resulted in significant regulatory reforms around exposure monitoring, reporting requirements and the establishment of a central exposure data base.
In January 2018 the Chief Inspector of Coal Mines requested all surface coal operations to provide personal exposure monitoring data collected since the introduction of the risk based legislation. This paper reviews exposure data collected from Queensland surface coal mines and wash plants during the period 2001 – 2017.
Specifically the paper discusses:
• Mean exposure trends across various similar exposure groups for respirable coal dust and respirable
crystalline silica (RCS)
• Personal monitoring programmes and sampling rates
• High dust exposure tasks and single exceedance data
In addition, the study draws comparison with exposure data collected from Queensland coal mines during the eighties (80’s).