WHS duties for businesses who work with crystalline silica substances

A PCBU must ensure that no person at the workplace is exposed to RCS, at a concentration above the workplace exposure standard. The workplace exposure standard for RCS is an eight-hour time weighted average (TWA) of 0.05 milligrams per cubic metre (mg/m³). 

More information is available on the Safe Work Australia webpage Guidance on interpretation of Workplace exposure standards for airborne contaminants.

Air monitoring involves measuring the level of RCS in the breathing zone of workers by using a personal sampler during their usual shift activities (including routine breaks). Air monitoring is important to:

• check the effectiveness of control measures
• monitor the workplace atmosphere to ensure the workplace exposure standard is not being exceeded
• help choose the right level of respiratory protection
• inform health-monitoring requirements.

Air monitoring results must be kept for 30 years after the record is made and be readily available to those who may be exposed to the substance or mixture in the workplace.

In assessing any processing of CSS, you must have regard to the results of any previous air monitoring that has been conducted at that workplace that are relevant to the task, controls and conditions in your workplace. If you do not have any previous air monitoring results, this does not prevent you from determining whether the processing of a CSS is high risk, rather you must undertake your assessment considering all the matters.

Some businesses and industries, such as the stone-benchtop industry have specific air monitoring requirements that are outlined in the Working with crystalline silica substances: Guide. 

PCBUs who carries out high risk processing of CSS, need to undertake air monitoring for RCS. If the monitoring results show the airborne concentration of RCS has exceeded the workplace exposure standard of 0.05 mg/m³ , the PCBU must report the results to the WorkSafe Commissioner using the notification form.

Health monitoring of a worker means monitoring the worker to identify changes in their health because of exposure to certain substances. It involves collecting data to measure exposure or evaluate its effects and determine whether the absorbed dose is within safe levels.

A PCBU must organise and pay for health monitoring if there is a risk to the health of their workers because of exposure to silica dust at the workplace. Health monitoring identifies any changes to the health of workers resulting from exposure to respirable crystalline silica (RCS).

Under the Work Health and Safety (General) Regulations 2022 (WHS General Regulations), the minimum requirements for health monitoring for crystalline silica through exposure to silica dust are:

• collection of demographics, medical and occupational history
• records of personal exposure
• standardised respiratory questionnaire
• standardised respiratory function tests, for example, FEV1 (forced expiratory volume in one second), FVC (forced vital capacity) and FEV1/FVC (respiratory ratio, or Tiffeneau index)
• low dose high resolution computed tomography of the chest at less than 1 millisievert (mSv) equivalent dose for the entire study. The study must image the whole of each lung on inspiration at 1.5 mm slice thickness or less, without an interslice gap, and must include expiratory imaging. The images must be of adequate quality to detect subtle abnormalities, including ground glass opacities and small nodules.

The registered medical practitioner who prepares the health monitoring report must give the regulator a copy if the report contains monitoring results consistent with exposure to silica. When conducting the assessment to determine if the processing of CSS is high risk, you must consider the results of any relevant health monitoring that has been previously conducted at the workplace.

More information on health monitoring of workers for exposure to crystalline silica can be found in the Health monitoring guide for registered medical practitioners: Silica (respirable crystalline)

Health monitoring records must be kept confidential and for at least 30 years after the record is made, even if the worker no longer works at the workplace.

Information about health monitoring reports is available in the Health monitoring duties for persons conducting a business or undertaking: Guide.

You must provide crystalline silica training for workers carrying out processing of a CSS:

• as a part of induction and refresher training
• any worker involved in processing of a CSS that is high risk; or
• who is at risk of exposure to RCS because of that processing.

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.

Crystalline silica training means training that is accredited or has been approved by the regulator in relation to health risks associated with exposure to respirable crystalline silica and the need for suitable risk control measures. Approval by the regulator follows assessment of whether the content address specified technical criteria but does not include assessment of course delivery. 

The following courses are recognised as nationally accredited training in Western Australia:

• 10830NAT Course in Crystalline Silica Exposure Prevention
• Units of competency for silica safety:
  • CPCSIL3001 - Work with products and materials containing crystalline silica; or
  • CPCSIL4001 - Supervise and manage work with products and materials generating respirable crystalline silica.

The following non-accredited course has been approved by the regulator: 

• HIA Silica awareness training
• NECA Managing risks of crystalline silica (WA)

You are required to keep a record of the training provided to workers, while they are carrying out the high risk processing and for five years after the day they stop working for your business. This record of training can be documented in your silica risk control plan.