Fritz Djukic Inspector, (Occupational Hygiene), Department of Natural Resources, Mines and Energy Inhalable dust refers to all dust that may enter the mouth and nose during normal breathing. Inhalable dust may be divided into ‘respirable’ and ‘non- respirable’ fractions. The dust particle size will ultimately determine the site of deposition within the respiratory system. Respirable dust particles (<10 micron) may penetrate deep into the gas exchange regions of the lung. The ‘non respirable’ faction includes both ‘extra thoracic dust particles (<100 micron)’ and ‘thoracic dust particles (<25 micron)’. The re-identification of CWP among Queensland coal mine workers and, more recently, the increase in cases of silicosis among engineered stone workers is a stark reminder of the hazards associated with exposure to respirable dust. Recent reforms to the respiratory component of the existing coal mine workers health scheme have resulted in major improvements with respect to the early detection and diagnosis of mine dust lung disease (MDLD). These improvements have led to a number of other forms of MDLD being detected among Queensland mine workers that are not associated with pneumoconiosis. A growing number of these cases fall into the broad category of chronic obstructive pulmonary disease (COPD). There is an increasing body of evidence implicating exposure to larger dust particles (outside the respirable fraction) and an inflammatory response in the lung, resulting in COPD. Unlike the Queensland metalliferous mining and quarrying legislation, there is currently no prescribed regulatory limit for inhalable dust in Queensland coal mining legislation. Despite this, the majority of coal mines have recognised this as a potential health hazard as part of their site health risk assessments (HRA). This paper reviews available inhalable dust exposure data that has been provided to the Mines Inspectorate for Queensland coal mines since the introduction of risk based legislation in 1999. The paper considers the evidence basis for regulatory amendment to ensure risk is at an acceptable level and as low as reasonably achievable.

Greg Manthey Inspector of Mines – Occupational Hygiene, Department of Natural Resources, Mines and Energy Effectively controlling worker exposure to respirable crystalline silica (RCS) in mineral mines and quarries (MMQ) is an ongoing challenge. Increasing cases of mine dust lung disease show this has not yet been met. RCS can cause silicosis, lung cancer, chronic bronchitis and emphysema after prolonged exposure. Acute silicosis can result after very high, short term exposure as tragically seen in the manufactured stone industry. The MMQ sector has nearly 1400 operational sites employing approximately 12,800 workers, many of them at elevated risk from RCS exposures. The 2017 introduction of the Guideline for the Management of Respirable Crystalline Silica in Mineral Mines and Quarries (QGL02) provided the industry with structures to address RCS exposure. Barriers to effective implementation include:

• limited understanding of the hazard,
• difficulty implementing effective dust control,
• limited number of Occupational Hygienists,
• monitoring costs,
• a generally poor understanding of QGL02.

DNRME’s compliance monitoring program continues the Inspectorate’s close engagement with the sector, ensuring SSE’s understand QGL02 and comply with their obligations including risk evaluation, exposure monitoring and reporting. This presentation describes findings from the program and focus areas, including:

• sampling results and data,
• compliance issues,
• at-risk groups
• increasing RCS education,
• improving risk identification and evaluating,
• effectiveness of control measures.

Darren Marinoff Principal Consultant – Occupational Hygiene, Greencap The high-risk nature of the Mining and Resources industry prescribes multiple layers of safety requirements that workers need to undertake to access a site and carry out specific works safely. Greencap’s depth of experience in occupational health and safety within the Mining and Resources Industry includes the organisation’s engagement by the South Australian Mining and Quarrying Health and Safety Committee to undertake Respirable Crystalline Silica (RCS) monitoring at various mines and quarries throughout South Australia as part of their Health Surveillance Program. This project alone saw over 1,000 personal and static monitoring samples collected throughout 2016 to 2018. This presentation will first give background information on the hazards of RCS dust and the risks of exposure. Analysis of the data collected from the monitoring programs will be presented with a focus on elevated exposures relating to Similar Exposure Groups, operational locations and mined/quarried products. Discussion will be presented on observations of existing controls and their effectiveness together with use of respiratory protective devices and a fit testing program conducted during the third year of the program.