Crystalline silica – technical fact sheet

This technical fact sheet explains the risks of working with respirable crystalline silica.

Crystalline silica is a common natural mineral used in many products and materials across a wide range of industries. Applying adequate controls such as minimising the generation of airborne dust can reduce hazardous exposures and prevent illness.

Sources of exposure

Materials and products containing crystalline silica include shale, sandstone, concrete, bricks, and manufactured stone. Workers may find crystalline silica during excavation or tunnelling through quartz-containing rock such as shale or sandstone. In its solid form, crystalline silica products are not harmful.

A health hazard is created when very fine particles of crystalline silica are inhaled. This airborne dust is known as respirable crystalline silica, or RCS.

Significant levels of harmful dust are most likely to occur when materials or products in the workplace are processed including cutting, sanding, drilling or other activities which create fine dust. Secondary exposures in workplaces can also occur through dry sweeping or using compressed air to clean silica contaminated surfaces, including clothing or fabric materials.

Health effects

RCS can cause a range of serious illnesses including silicosis, lung cancer and kidney disease, depending on how much dust a worker breathes in and for how long. Silicosis is a fibrosis (scarring) of the lung resulting in loss of lung function. This fibrosis is incurable and continues to develop after exposure has stopped. Anyone with advanced silicosis can suffer severe shortness of breath and may suffer complications such as heart failure.

Silicosis can be classed into:

  • chronic (or classic) silicosis, typically observed in workers following ten years or more exposure
  • accelerated silicosis, appearing in workers after high exposure over a shorter period (one to ten years)
  • acute silicosis, observed in workers usually less than one year after exposure to silica at very high concentrations. Acute silicosis can cause very serious health effects and is life threatening.

Significant long term exposure to RCS has also been associated with an increased risk of developing lung cancer.

Labelling and safety data sheets

Manufacturers need to label their products if they contain hazardous substances such as crystalline silica and provide a current Safety Data Sheet (SDS). A SDS will provide details on what the product is made of, as well as hazard identification and precautionary information. It will also include suggested controls, like engineering controls and personal protective equipment. Suppliers and importers must also ensure these products are correctly labelled when supplied to workplaces and provide a SDS.

A person conducting a business or undertaking (PCBU) must obtain a copy of the SDS and make it readily accessible to workers involved in using, handling, storing, or processing activities involving crystalline silica at a workplace.

Workplace exposure standards and air monitoring

Respirable crystalline silica has a workplace exposure standard (WES) of 0.05 mg/m3 averaged over eight hours, or adjusted WES for extended work shifts, (for example, 12hr shifts). PCBUs must ensure that no person at the workplace is exposed to a substance above its exposure standard and must reduce exposures so far as is reasonably practicable.

PCBUs are required to undertake air monitoring to determine the airborne concentration of a substance or mixture which has a WES if:

  • they are uncertain on reasonable grounds whether or not the airborne concentration of RCS at the workplace exceeds the WES for RCS, or
  • monitoring is necessary to determine whether there is a risk to health from RCS at the workplace.

Air monitoring results must be provided to workers and records of results kept for 30 years.

Air monitoring must be conducted by a suitably qualified person. Monitoring should be done in the worker’s breathing zone for the duration of a worker’s shift to gauge the average amounts that they would be exposed to during normal work activities.

For any air monitoring conducted after 1 September 2024, it is compulsory to notify SafeWork NSW of any air monitoring results that exceed the WES. You must notify SafeWork NSW via the online notification form, within 14 days of receiving the report.

How to report a Workplace Exposure Standard (WES) exceedance.

Health monitoring

PCBUs are required to provide health monitoring to workers if there is a significant risk to the worker’s health because of ongoing exposure to respirable crystalline silica.

Crystalline silica is listed in Schedule 14 of the WHS Regulation 2017 which outlines the health monitoring requirements.

PCBUs must:

  • inform workers of the requirements for health monitoring
  • use a registered medical practitioner with experience in health monitoring
  • provide details to the medical practitioner
  • obtain a copy of the health monitoring report
  • provide a copy of the report to the worker
  • provide a copy of the health monitoring report to SafeWork NSW if the worker has developed a disease or injury because of exposure, or the report contains any recommendations on remedial measures at the workplace
  • keep records of health monitoring for 30 years.

Workers exposed to RCS at levels or a frequency not resulting in a significant risk to health, are not required to undergo health monitoring. Workers relying on personal protective equipment (PPE) such as respirators for controlling their exposure below the exposure standard must be included in health monitoring.

How to notify SafeWork NSW of an adverse health monitoring report.

Control measures

Where risks to health and safety cannot be eliminated, the hierarchy of controls must be applied to minimise risk. For instance, to control the risk of exposure to RCS you must apply the following controls where reasonably practicable:

  • apply water suppression systems to reduce dust generation
  • use local exhaust ventilation systems to remove dust at the source
  • ensure such ventilation is correctly placed and operates at effective flow rates
  • use dust removal systems on tools to reduce dust exposure to mobile workers
  • isolate areas of the workplace where dust is generated
  • ensure regular housekeeping in dusty work areas to prevent the accumulation of dust
  • provide suitable PPE, including a program to correctly fit, instruct on use and ensure regular maintenance of respiratory protective equipment (RPE).

Control measures must be regularly reviewed and revised, as necessary, to ensure they remain effective. Any changes to work systems and procedures must be completed in consultation with workers and any health and safety representatives in the workplace.

Any worker involved in high-risk silica work activities or workers who may be at risk of exposure to RCS because of that work activity must complete an approved crystalline silica training course.

In NSW there is now a set of criteria that courses must meet to satisfy training requirements. This means that if you want to develop in-house training or arrange training to be delivered by a third party, and that training meets the criteria, this will be considered ‘regulator-approved training’. The existing approved courses are also still available.

If your workers are not undertaking high risk processing, you must still provide appropriate information, instruction, training or supervision to anyone who may be exposed to RCS at the workplace.

Legacy engineered stone

Any work involving the manufacture, supply, processing, or installation of engineered stone was banned on 1 July 2024. The ban applies to benchtops, panels and slabs made from engineered stone with a greater than 1% crystalline silica content.

If you or your workers are removing, repairing or making minor modifications to engineered stone products that were installed prior to 1 July 2024 (referred to as legacy engineered stone), you must notify SafeWork NSW. The requirement to notify also applies to the disposal of engineered stone whether installed or not.

When to notify:

  • annually, estimating the type and amount of processing work for the next 12 months
  • before starting work or directing workers
  • if work changes (e.g. frequency or type), even if you have already notified.

If you unknowingly process legacy engineered stone, you must notify immediately.

How to notify work on legacy engineered stone.

More information

Codes of practice

These codes of practice provide practical guidance and information on how to meet your legal obligations:

Safe Work Australia guidance material

Australian Standards

Other resources

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