As COVID-19 dominates the safety landscape, quarries are being urged not to lose sight of other OHS considerations – particularly compliance with revised exposure standards to airborne hazardous substances like respirable crystalline silica. Damian Christie reports.
Occupational lung diseases have long occurred in workers that have been exposed without sufficient protection to certain industrial materials in the workplace. Pneumoconiosis in particular can occur due to an accumulation of dust in the lungs, and the most common of these diseases are asbestosis, silicosis and coal workers’ pneumoconiosis (CWP, also more commonly known as black lung disease). Pneumoconiosis can be exacerbated further by smoking and can lead to chronic obstructive pulmonary diseases (COPD), including bronchitis, emphysema and lung cancer.
Historically, silicosis is believed to have afflicted miners and extractive workers since the times of the ancient Greeks and Romans. Lung problems from inhalation of dust was written about in European medical journals dating back to the 17th century before physician Achille Visconti (1836-1911) coined the term “silicosis” (from the Latin silex, or flint), better known in the industry today as respirable crystalline silica (RCS). Inevitably, the incidence of silicosis in workers increased with the industrialisation of the mining and extractive industries in the 19th and 20th centuries. Up to 55,000 workers globally died from silicosis in 1990. Although annual numbers have declined, as of 2013, the global annual total stood at around 46,000. The decline has been more noticeable in developed countries such as the United States; in 1968, more than 1000 workers per annum in the US died of the disease but by 2005, this number had dropped significantly to 170 per annum.
It has been established that RCS can be found in most rocks, sands and clays, as well as end products such as concrete, bricks, blocks, pavers and cementitious materials. The dust is often produced through high energy processes such as crushing, drilling, sawing and grinding.1
In Australia, inaccurate historical data about RCS makes it difficult to estimate just how many workers in the extractive industries have suffered from the disease in the past century. According to the Australian Institute of Health and Welfare, the death rate for pneumoconiosis (including RCS) has fallen since the 1950s when the male age-standardised rate peaked at 3.9 deaths per 100,000 population. In the period 1980 to 2005, the mortality rate was less than one per 100,000 population. The sharp decline and levelling of the mortality rate was attributed to decreased exposure to hazardous dusts and the time lag between exposure and death.2
However, while pneumoconiosis and other respiratory diseases were thought to have been almost eliminated by the turn of the 21st century, they have never really disappeared and still remain a risk to workers when adequate controls are not in place. According to the Australian Cancer Council, 587,000 Australian workers were exposed to silica dust on the job in 2011, and about 5758 of that cohort is expected
to develop lung cancer in the future from that exposure.3
More recently, hazardous dust diseases were thrust into the spotlight because of two separate cases:
1. The diagnosis of CWP in 21 Queensland coal workers. The Queensland Parliament conducted an inquiry into the re-identification of CWP in 2017. It established that CWP in Queensland was never “eradicated”, it merely had not been detected or identified by responsible Queensland authorities for more than three decades. Of the 68 recommendations in the report, there was a strong emphasis on improving the regulatory regime.4
2. The identification of 35 Queensland stone masons (particularly in the artificial stone benchtop industry) with RCS, on top of other cases identified in New South Wales, Victoria and the ACT, in late 2018. The Federal Health Minister Greg Hunt called on the states to consider the formation of a national dust diseases register.5
Partly in response to the above cases, in late 2019, the statutory body Safe Work Australia, with the support of the Council of Australian Governments (COAG) health ministers, developed new Workplace Exposure Standards for Airborne Contaminants (WESFAC) to protect workers across the mining, quarrying, construction and masonry industries from airborne contaminants, including RCS. The body recommended that the WESFAC be reduced by half – from the eight-hour time-weighted average (TWA) of 0.1 milligrams per cubic metre (mg/m3) to 0.05 mg/m3 under the Work Health and Safety Regulations 2011.6 This was a further reduction in the WESFAC, which was introduced in 2005 at 0.2mg/m3. The COAG ministers unanimously agreed to implement the new standard, which required changes to the harmonised Work Health & Safety Act in each jurisdiction.
As a follow-on to point 2 above, the Federal Government also convened a National Dust Disease Taskforce in June 2019 to investigate the “emerging trend of new cases” of RCS in workers. It committed $5 million to support the Taskforce and related measures, including the establishment of a National Dust Diseases Register, and new research to support comprehension, prevention and treatment of occupational dust diseases.7
The Taskforce, which was initially chaired by Professor Brendan Murphy, the most recent national chief medical officer in the coronavirus response, has stalled due to COVID-19 and is now not required to deliver its final report until 30 June, 2021.
While the management of dust is a vital issue for quarries, not all quarries will lead to exposure to RCS for workers. The level of risk will depend on the concentration of RCS in the rock, processing methods and the controls used at the site.
ACROSS THE JURISDICTIONS
With the exception of Victoria, Western Australia and Tasmania, the revised WESFAC took effect in most jurisdictions of Australia from 1 July, 2020. Victoria was the earliest adopter, with the WESFAC being introduced on 17 December, 2019.
So what does the new workplace exposure standard for RCS mean for quarrying and other extractive operations? It will depend on where each operation is based and how quickly the abiding jurisdiction will introduce and enforce the exposure standard.
As the NSW Resources Regulator’s chief inspector of mines Garvin Burns told Quarry in late 2019, quarries must undertake a multi-tiered approach to managing dust. “First, you manage or eliminate it at its source if you can,” he said. “If you can’t, then you suppress it. And if you can’t eliminate or suppress it, then you keep people out of it.”
Burns’ remarks came after a targeted intervention into airborne dust in more than 20 quarries by the NSW Resources Regulator in late 2019 resulted in numerous improvement notices and notices of concern. He said that inspectors were particularly disappointed that there was a singular reliance in these operations on personal protective equipment (PPE) as a risk control for respirable dust and the misunderstanding that employees could work in heightened dust conditions if they were wearing PPE. The intervention program was launched after a review of dust monitoring results in May 2019 indicated some quarry workers were being exposed
to dust at levels above the prescribed WESFAC limits.
“Some [operations] did have good controls in place in terms of things like sprays and screens and hoods, and workers understood the importance of these being in place,” Burns said. “Some quarries also reacted very quickly to the notices that were issued to them. In a very short period of time they had actually gone and implemented quite good dust controls, with regards to putting hoods on transfer points on conveyors, fitment of sprays, and conveyor transfers and sprays on stockpiles.
“But we also had operations where there were piles of dust under rollers and conveyors, float dust that was piled up a foot deep, and that dust is constantly getting disturbed when workers walk through those areas.”8
For the purposes of this article, Quarry contacted the regulator to determine if there had been any resolutions since the targeted intervention. A spokesman for Burns confirmed the NSW Resources Regulator had followed up on the notices issued during the intervention with no non-compliance issues identified.
“We have continued conducting airborne dust planned inspections at quarries, purchased three real-time dust monitoring devices to be used by inspectors during site inspections, and offered free dust monitoring for small mines that met the specified criteria,” the spokesman said.9
The representative added the NSW Resources Regulator in July released a new list of compliance priorities to the end of 2020 that incorporates airborne contamination, including RCS, and dust control. It announced the project would
be multi-faceted, incorporating site assessment and engagement with the extractive industry through a variety of mediums, including information sessions and training workshops from July to November (due to COVID-19, many of these sessions are likely to be virtual).10
The regulator also said it would continue to regulate as per the policy position outlined in its March 2020 discussion paper.11 The spokesman for Burns added that the regulator continues to develop and provide guidance to the quarrying sector about dust. A toolkit to provide information, advice and guidance has recently been launched12 and the regulator publishes quarterly reports13 on mine safety performance, including issues about dust and highlighting good practice case studies and examples.
“In addition to these resources, a small mines regional roadshow is conducted every year which quarry operators are encouraged to attend,” he added. “Details of this year’s roadshow will be announced soon.”
The NSW Mine Safety Advisory Council (MSAC) has also recently launched a new awareness campaign to educate mine and quarry workers – Just because you can’t see it, doesn’t mean it’s not there – about the health impacts of dust and dust prevention measures. The campaign provides insights from health and safety, and industry officials, along with an online toolkit.14
The Resources Regulator’s compliance strategy and MSAC’s awareness campaign are all part of the NSW Government’s Silicosis Reduction Strategy, which, in addition to introducing the new WESFAC, has also mandated a ban on the dry cutting and grinding of stone and manufactured stone in the manufactured stone industry, and now requires medical practitioners to notify NSW Health of a diagnosis of RCS. Penalties will also apply for any organisation that fails to notify SafeWork NSW of an adverse health monitoring report.15
The Australian Capital Territory has taken a much stronger line of the six jurisdictions to adopt the new WESFAC, arguing that there should be further reductions to them in future. Suzanne Orr, the ACT’s minister for employment and workplace safety, has said the ACT Government is encouraging businesses to go lower as even at an eight-hour TWA of 0.05mg/m3, there is the potential for workers to still develop adverse health conditions.
“The recommended health-based exposure standard for silica dust is actually 0.02mg/m3 and the ACT Government will be working closely with other jurisdictions to further reduce workplace exposure standards over the next two years,” Orr said. “As technology is better able to measure the lower standard of 0.02mg/m3, national work health and safety requirements should be decreased.”16
Similarly, WorkSafe Victoria also recommends that while construction materials organisations should not exceed the TWA airborne concentration of 0.05mg/m3, it recommends employees not be exposed to levels above 0.02mg/m3.17
The other jurisdictions have all pointed to various audit findings and compliance campaigns they have conducted in the past two years – in addition to adopting the revised WESFAC – as evidence of their support for reducing the incidence of RCS in extractive workers. Western Australia, which has only recently introduced its own mirror version of the Work Health and Safety Act (almost nine years after it was originally introduced by the Commonwealth), and Tasmania, which also follows the harmonised WHS Act model, are yet to announce when the revised workplace exposure standard for RCS will be introduced into their jurisdictions.
INDUSTRY RESOURCES
All quarrying and extractive businesses are encouraged to visit the websites of the relevant earth resources and safety regulators in their jurisdictions to learn more about how they can comply with the new workplace exposure standard for RCS and also engage in the campaigns those regulators are promoting.
Closer to home, the IQA and Cement Concrete Aggregates Australia (CCAA) can also provide educational materials that can assist construction materials businesses with revamping their safe work practices in line with the revised WESFAC.
IQA President Shane Braddy told Quarry in late 2019 that quarries “need to understand the hierarchy of controls and ensure workers are protected. The IQA is building on the guidelines available in industry and will be conducting very specific training in 2020”.18
The IQA has launched its RCS resources in the past few months. They include:
• Awareness fact sheets and webinars that are available free of charge at the IQA website – quarry.com.au19
• In-depth workshops to educate the industry on product exposure, health and safety, and compliance with the new exposure standards. The first of the workshops will be held on 8 October in Queensland (venue to be confirmed).
• Pending state COVID-19 restrictions, further workshops (or virtual workshops) will be released.
Like the IQA, the CCAA is offering similar resources, including its own guidelines, which were originally published in 2018 and updated earlier this year. The guidelines include a toolbox talk form for engaging workers. 20
Indeed, Garvin Burns cited the CCAA guidelines on RCS as an “extremely good resource” for quarry operations to follow when he spoke to Quarry late last year.
“If quarry operators were to pick up that guideline and read it properly and implement some of the recommendations in there, they would be in a much better place,” he said at the time.21 •
REFERENCES & FURTHER READING
1 Workcover Queensland. Construction dust: Respirable crystalline silica. Last updated: 10 July, 2020. worksafe.qld.gov.au/construction/workplace-hazards/silica-exposure-a-serious-risk-for-construction-workers
2 Australian Institute of Health & Welfare (AIWH). Chronic respiratory diseases in Australia: Their prevalence, consequences and prevention. AIWH, August 2005. aihw.gov.au/getmedia/0f281915-2937-4015-a8d0-9abd3990f976/crdapcp.pdf.aspx?inline=true
3 Cancer Council. Silica dust. https://www.cancer.org.au/preventing-cancer/workplace-cancer/silica-dust.html
4 Coal Workers’ Pneumoconiosis Select Committee. Inquiry into the re-identification of Coal Workers’ Pneumoconiosis in Queensland – Interim Report. Report No. 2, 55th Queensland Parliament, 29 May 2017. parliament.qld.gov.au/Documents/TableOffice/TabledPapers/2017/5517T815.pdf
5 Atkin M. Federal Government calls on states to undertake immediate investigation into silicosis risk. ABC News; 18 October, 2018. abc.net.au/news/2018-10-11/federal-government-calls-for-investigation-into-silicosis/10365146
6 SafeWork Australia. Workplace Exposure Standards for airborne contaminants. 18 December, 2019. ISBN 978-1-76051-898-1 [Online PDF]. safeworkaustralia.gov.au/system/files/documents/1912/workplace-exposure-standards-airborne-contaminants.pdf
7 Federal Department of Health. National Dust Disease Taskforce. www1.health.gov.au/internet/main/publishing.nsf/Content/ohp-nat-dust-disease-taskforce.htm
8 Hume M. NSW regulator vows to prioritise dust control. Quarry 28(2); February 2020: 11. Originally published 1 December, 2019. quarrymagazine.com/2019/12/01/nsw-regulator-vows-to-prioritise-dust-control/
9 Email from a spokesperson for NSW Resources Regulator Garvin Burns, dated 21 July, 2020.
10 Zakharia N. Resources Regulator to tackle health, safety risks in quarries. Quarry, 20 July 2020. quarrymagazine.com/2020/07/17/resources-regulator-to-tackle-health-safety-risks-in-quarries/
11 NSW Resources Regulator. Revision to Silica Exposure Standard (Position Paper), March 2020. resourcesregulator.nsw.gov.au/__data/assets/pdf_file/0007/1207339/Position-Paper-Revision-to-silica-exposure-standard.pdf
12 NSW Resources Regulator. Take action to prevent dust disease toolkit. resourcesregulator.nsw.gov.au/safety-and-health/about-us/advisory-council/msac-dust-toolkit
13 NSW Resources Regulator. Activity and safety reports. https://www.resourcesregulator.nsw.gov.au/compliance-and-enforcement/business-activity-reports
14 Zakharia N. NSW promotes dust, health competency in quarries, mines. In: Quarry 28(7); August 2020: 12. Originally published 3 July 2020. quarrymagazine.com/2020/07/03/nsw-promotes-dust-health-competency-in-quarries-mines/
15 SafeWork NSW. Crystalline silica. safework.nsw.gov.au/hazards-a-z/hazardous-chemical/priority-chemicals/crystalline-silica
16 Silica WES halved across six jurisdictions. In: NSCA Foundation Ltd Safety-T-Bulletin. 8 July, 2020. nscafoundation.org.au/news-item/4994/silica-wes-halved-across-six-jurisdictions
17 Dust containing crystalline silica in construction work. WorkSafe Victoria, 24 December 2019. https://www.worksafe.vic.gov.au/dust-containing-crystalline-silica-construction-work
18 Hume M. NSW regulator vows to prioritise dust control. Quarry 28(2); February 2020: 11. Originally published 1 December, 2019. quarrymagazine.com/2019/12/01/nxsw-regulator-vows-to-prioritise-dust-control/
19 Institute of Quarrying Australia Fact Sheets. quarry.com.au/IQA/Education/Fact_Sheets/Public/Fact_Sheets.aspx?hkey=cd60f158-f0ea-40f1-a754-74d435566817
20 Cement Concrete Aggregates Australia. Workplace Health & Safety Guideline: Management of Respirable Crystalline Silica in Quarries. September 2018. ccaa.com.au/imis_prod/documents/CCAA_Guidelines_for_Quarries_web_spreads.pdf
21 Hume M. NSW regulator vows to prioritise dust control. Quarry 28(2); February 2020: 11. Originally published 1 December, 2019. quarrymagazine.com/2019/12/01/nsw-regulator-vows-to-prioritise-dust-control/