Marked changes for good have emerged from the Queensland government following lowering of dust control limits in 2020 and the introduction of stands such as Recognised Standard 20.  The critical and much needed changes in the allowable limits for respirable coal and silica dust in Queensland came into effect. The effected changes in dust control limits in Queensland came as a result of extensive efforts and lobbying from Safework Australia which also extended in effect to all metalliferous mine workers and quarry workers across the states in Australia. Workplace safety and health is paramount to the discussions of Queensland and dust control limits as the resurgence of coal mine workers pneumoconiosis in 2015 brought to fore a problem that had previously been dismissed as completely eradicated in the last 30 years. Getting a bit more into the numerical changes to the dust control limits in Queensland, the reduction of respirable coal dust limits were lowered by 1 milligram per cubic meter from 2.5 milligrams per cubic meter to 1.5 milligrams per cubic meter. Silica dust was also reduced by about 0,95 milligrams per cubic meter from 1 milligram per cubic meter to 0.05 milligrams per cubic meter. The drive for workplace safety and health in Queensland was definitely a notable reform on the part of the government with reinforcement to the reforms complemented with mine workers free respiratory health checks for life. This article evaluates history of coal mining in Queensland, the resurgence of coal mine workers pneumoconiosis and analyses products utilized for coal and silica dust suppression from the GRT product range. 

Where did coal mining in Queensland start?

The mining of coal in Queensland dates back to the first sightings on the banks of the Brisbane River within a year of the establishment of a settlement on Moreton Bay, through the granting of independent status to Queensland in 1859 to the opening of the railway from Ipswich to Brisbane in 1874. In fact it is believed that John Oxley, the surveyor-general of New South Wales first noticed coal in the Brisbane Rive in 1824 but did not enter details of the supposed discovery. A year later, Major Edmund Lockyer visited the Brisbane River and diarized having passed a very rapid fall coal bed as well as going on to collect a sample of the coal. A few years later, in 1828 arrival of Charles Fraser at Brisbane town in the company of Allan Cunningham and Captain Logan with whom they rowed up the Brisbane and Bremer rivers to the “Limestone Station” present day Ipswich. Fraser noted several beds of coal which were adjacent to lime outcropping from the bank of the streams and falling into the Bremer within a short distance from its tide mark. In 1828 the Australian Agricultural Company was granted the exclusive privilege for supplying coal to the public in the colony and it centered its operations on Newcastle in the interest of removing any prospective competition from other sources. The history of coal mining in Queensland from a documentation and exploratory evidence is then attributed to Lockyer, Logan, Fraser and Cunningham. 

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Queensland – from penal colony to state

1842 marked a year in which the penal settlement at Moreton Bay was closed and this allowed free access, travel and work within the previously closed fifty mile radius of Brisbane Town. In relation to coal mining, the changes were not much of an incentive with bulk of the coal use in the 19th century mainly as a source of fuel and better option to wood. The transition from manual labor to mechanization created a market for growing use of coal as a steam raising fuel. Geologically in the 1850s, events such as construction of railways, the production of gas for heat and light and the advent of industrial production in South Australia left Queensland coal reserves almost untouched for almost a decade. Post the Lockyer and crew era, 1844-85 brought more news about coal discoveries at a couple of places between the Darling Downs and the Mackenzie River according to the Leichhardt expedition. A few years later, Clarke estimated that the ‘Coalfield of the Condamine’ on the Darling Downs covered an area of not less than 50 thousand square kilometers. The introduction of the steamship is very much tied to the early mining of coal in Queensland. 

When did black lung first emerge?

History has it that the first case of coal mine workers’ pneumoconiosis was reported by Gregory in 1831, although it should be stated that initially coal mine workers pneumoconiosis was thought of as a variant of silicosis because of similarity in chest radiographs, with the thought of coal dust to be innocuous. Most of the limits for coal dust were derived from a British study that produced the only quantitative exposure-response relationship available at the time. The basis of coal dust limit of 2 milligrams per cubic meter was chosen on the premise that among miners who worked 35 years with respirable coal dust there would not be any severe cases. However, research on US underground coal mine workers showed that there was no threshold at 2 milligrams per cubic meter under which the coal mine workers pneumoconiosis cases would not occur. More evidence suggested that coal mine workers pneumoconiosis, progressive massive fibrosis and chronic pulmonary disease may actually develop at the current permissible exposure limit of 2 milligrams per cubic meter. Recommendations of exposure limits of 1 milligram per cubic meter in the US, happened in 1995 and only 19 years later limits of respirable dust concentration was reduced to 1.5 milligrams per cubic meter in 2014 as a result of prevalence in coal mine workers pneumoconiosis dating as far back as 2003. Similarly in Queensland, the resurgence of coal mine workers pneumoconiosis in Queensland, in 2015 has also led to much of the marked reforms which have seen lowering of respirable coal dust allowable limits from 2 milligrams per cubic meter to 1 milligram per cubic meter in 2020 about 5 years later. 

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What is the best practice coal dust suppression?

It is imperative to tackle coal dust at the source given that exposure to coal dust leads to coal mine workers’ pneumoconiosis which may develop into progressive massive fibrosis and eventually become fatal to coal mine workers. Coal dust suppression is massively affected by particle size which also directly affects its reaction rate, sedimentation, solubility and human health. Research shows that coal consists of about 76 elements, and amongst these elements’ toxic elements such as arsenic, mercury and lead which are potentially hazardous to human health. The different functional groups in coal render it predominantly hydrophobic this in addition to free radicals that exist in coal. It is then very important to use effective dust control solutions for the prevention of exposure to coal mine workers at the source. Global Road Technology offers effective coal dust suppression products that reduce the need to constantly use water, do not affect the calorific value of coal and above all make water work. Making water work is achieved through superactivation of water enabling the hydrophobicity of coal to be matched with the hydrophobicity of GRT Activate and GRT Activate UG for your coal dust suppression. A full strategy from Pit to Port can effectively manage coal dust at its source, with additional options including GRT: Haul-Loc, GRT: Wet-Loc and GRT7000. In Queensland, dust control limits are met with innovative solutions from GRT that allow coal dust values to stay below limits and achieved through tackling coal dust at the source. 

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